aboutsummaryrefslogtreecommitdiffstats
path: root/drivers/gpu/drm/i915/gt/intel_execlists_submission.c
diff options
context:
space:
mode:
Diffstat (limited to 'drivers/gpu/drm/i915/gt/intel_execlists_submission.c')
-rw-r--r--drivers/gpu/drm/i915/gt/intel_execlists_submission.c6117
1 files changed, 6117 insertions, 0 deletions
diff --git a/drivers/gpu/drm/i915/gt/intel_execlists_submission.c b/drivers/gpu/drm/i915/gt/intel_execlists_submission.c
new file mode 100644
index 000000000000..e1d35ab17e6f
--- /dev/null
+++ b/drivers/gpu/drm/i915/gt/intel_execlists_submission.c
@@ -0,0 +1,6117 @@
+// SPDX-License-Identifier: MIT
+/*
+ * Copyright © 2014 Intel Corporation
+ */
+
+/**
+ * DOC: Logical Rings, Logical Ring Contexts and Execlists
+ *
+ * Motivation:
+ * GEN8 brings an expansion of the HW contexts: "Logical Ring Contexts".
+ * These expanded contexts enable a number of new abilities, especially
+ * "Execlists" (also implemented in this file).
+ *
+ * One of the main differences with the legacy HW contexts is that logical
+ * ring contexts incorporate many more things to the context's state, like
+ * PDPs or ringbuffer control registers:
+ *
+ * The reason why PDPs are included in the context is straightforward: as
+ * PPGTTs (per-process GTTs) are actually per-context, having the PDPs
+ * contained there mean you don't need to do a ppgtt->switch_mm yourself,
+ * instead, the GPU will do it for you on the context switch.
+ *
+ * But, what about the ringbuffer control registers (head, tail, etc..)?
+ * shouldn't we just need a set of those per engine command streamer? This is
+ * where the name "Logical Rings" starts to make sense: by virtualizing the
+ * rings, the engine cs shifts to a new "ring buffer" with every context
+ * switch. When you want to submit a workload to the GPU you: A) choose your
+ * context, B) find its appropriate virtualized ring, C) write commands to it
+ * and then, finally, D) tell the GPU to switch to that context.
+ *
+ * Instead of the legacy MI_SET_CONTEXT, the way you tell the GPU to switch
+ * to a contexts is via a context execution list, ergo "Execlists".
+ *
+ * LRC implementation:
+ * Regarding the creation of contexts, we have:
+ *
+ * - One global default context.
+ * - One local default context for each opened fd.
+ * - One local extra context for each context create ioctl call.
+ *
+ * Now that ringbuffers belong per-context (and not per-engine, like before)
+ * and that contexts are uniquely tied to a given engine (and not reusable,
+ * like before) we need:
+ *
+ * - One ringbuffer per-engine inside each context.
+ * - One backing object per-engine inside each context.
+ *
+ * The global default context starts its life with these new objects fully
+ * allocated and populated. The local default context for each opened fd is
+ * more complex, because we don't know at creation time which engine is going
+ * to use them. To handle this, we have implemented a deferred creation of LR
+ * contexts:
+ *
+ * The local context starts its life as a hollow or blank holder, that only
+ * gets populated for a given engine once we receive an execbuffer. If later
+ * on we receive another execbuffer ioctl for the same context but a different
+ * engine, we allocate/populate a new ringbuffer and context backing object and
+ * so on.
+ *
+ * Finally, regarding local contexts created using the ioctl call: as they are
+ * only allowed with the render ring, we can allocate & populate them right
+ * away (no need to defer anything, at least for now).
+ *
+ * Execlists implementation:
+ * Execlists are the new method by which, on gen8+ hardware, workloads are
+ * submitted for execution (as opposed to the legacy, ringbuffer-based, method).
+ * This method works as follows:
+ *
+ * When a request is committed, its commands (the BB start and any leading or
+ * trailing commands, like the seqno breadcrumbs) are placed in the ringbuffer
+ * for the appropriate context. The tail pointer in the hardware context is not
+ * updated at this time, but instead, kept by the driver in the ringbuffer
+ * structure. A structure representing this request is added to a request queue
+ * for the appropriate engine: this structure contains a copy of the context's
+ * tail after the request was written to the ring buffer and a pointer to the
+ * context itself.
+ *
+ * If the engine's request queue was empty before the request was added, the
+ * queue is processed immediately. Otherwise the queue will be processed during
+ * a context switch interrupt. In any case, elements on the queue will get sent
+ * (in pairs) to the GPU's ExecLists Submit Port (ELSP, for short) with a
+ * globally unique 20-bits submission ID.
+ *
+ * When execution of a request completes, the GPU updates the context status
+ * buffer with a context complete event and generates a context switch interrupt.
+ * During the interrupt handling, the driver examines the events in the buffer:
+ * for each context complete event, if the announced ID matches that on the head
+ * of the request queue, then that request is retired and removed from the queue.
+ *
+ * After processing, if any requests were retired and the queue is not empty
+ * then a new execution list can be submitted. The two requests at the front of
+ * the queue are next to be submitted but since a context may not occur twice in
+ * an execution list, if subsequent requests have the same ID as the first then
+ * the two requests must be combined. This is done simply by discarding requests
+ * at the head of the queue until either only one requests is left (in which case
+ * we use a NULL second context) or the first two requests have unique IDs.
+ *
+ * By always executing the first two requests in the queue the driver ensures
+ * that the GPU is kept as busy as possible. In the case where a single context
+ * completes but a second context is still executing, the request for this second
+ * context will be at the head of the queue when we remove the first one. This
+ * request will then be resubmitted along with a new request for a different context,
+ * which will cause the hardware to continue executing the second request and queue
+ * the new request (the GPU detects the condition of a context getting preempted
+ * with the same context and optimizes the context switch flow by not doing
+ * preemption, but just sampling the new tail pointer).
+ *
+ */
+#include <linux/interrupt.h>
+
+#include "i915_drv.h"
+#include "i915_perf.h"
+#include "i915_trace.h"
+#include "i915_vgpu.h"
+#include "intel_breadcrumbs.h"
+#include "intel_context.h"
+#include "intel_engine_pm.h"
+#include "intel_execlists_submission.h"
+#include "intel_gt.h"
+#include "intel_gt_pm.h"
+#include "intel_gt_requests.h"
+#include "intel_lrc_reg.h"
+#include "intel_mocs.h"
+#include "intel_reset.h"
+#include "intel_ring.h"
+#include "intel_workarounds.h"
+#include "shmem_utils.h"
+
+#define RING_EXECLIST_QFULL (1 << 0x2)
+#define RING_EXECLIST1_VALID (1 << 0x3)
+#define RING_EXECLIST0_VALID (1 << 0x4)
+#define RING_EXECLIST_ACTIVE_STATUS (3 << 0xE)
+#define RING_EXECLIST1_ACTIVE (1 << 0x11)
+#define RING_EXECLIST0_ACTIVE (1 << 0x12)
+
+#define GEN8_CTX_STATUS_IDLE_ACTIVE (1 << 0)
+#define GEN8_CTX_STATUS_PREEMPTED (1 << 1)
+#define GEN8_CTX_STATUS_ELEMENT_SWITCH (1 << 2)
+#define GEN8_CTX_STATUS_ACTIVE_IDLE (1 << 3)
+#define GEN8_CTX_STATUS_COMPLETE (1 << 4)
+#define GEN8_CTX_STATUS_LITE_RESTORE (1 << 15)
+
+#define GEN8_CTX_STATUS_COMPLETED_MASK \
+ (GEN8_CTX_STATUS_COMPLETE | GEN8_CTX_STATUS_PREEMPTED)
+
+#define CTX_DESC_FORCE_RESTORE BIT_ULL(2)
+
+#define GEN12_CTX_STATUS_SWITCHED_TO_NEW_QUEUE (0x1) /* lower csb dword */
+#define GEN12_CTX_SWITCH_DETAIL(csb_dw) ((csb_dw) & 0xF) /* upper csb dword */
+#define GEN12_CSB_SW_CTX_ID_MASK GENMASK(25, 15)
+#define GEN12_IDLE_CTX_ID 0x7FF
+#define GEN12_CSB_CTX_VALID(csb_dw) \
+ (FIELD_GET(GEN12_CSB_SW_CTX_ID_MASK, csb_dw) != GEN12_IDLE_CTX_ID)
+
+/* Typical size of the average request (2 pipecontrols and a MI_BB) */
+#define EXECLISTS_REQUEST_SIZE 64 /* bytes */
+
+struct virtual_engine {
+ struct intel_engine_cs base;
+ struct intel_context context;
+ struct rcu_work rcu;
+
+ /*
+ * We allow only a single request through the virtual engine at a time
+ * (each request in the timeline waits for the completion fence of
+ * the previous before being submitted). By restricting ourselves to
+ * only submitting a single request, each request is placed on to a
+ * physical to maximise load spreading (by virtue of the late greedy
+ * scheduling -- each real engine takes the next available request
+ * upon idling).
+ */
+ struct i915_request *request;
+
+ /*
+ * We keep a rbtree of available virtual engines inside each physical
+ * engine, sorted by priority. Here we preallocate the nodes we need
+ * for the virtual engine, indexed by physical_engine->id.
+ */
+ struct ve_node {
+ struct rb_node rb;
+ int prio;
+ } nodes[I915_NUM_ENGINES];
+
+ /*
+ * Keep track of bonded pairs -- restrictions upon on our selection
+ * of physical engines any particular request may be submitted to.
+ * If we receive a submit-fence from a master engine, we will only
+ * use one of sibling_mask physical engines.
+ */
+ struct ve_bond {
+ const struct intel_engine_cs *master;
+ intel_engine_mask_t sibling_mask;
+ } *bonds;
+ unsigned int num_bonds;
+
+ /* And finally, which physical engines this virtual engine maps onto. */
+ unsigned int num_siblings;
+ struct intel_engine_cs *siblings[];
+};
+
+static struct virtual_engine *to_virtual_engine(struct intel_engine_cs *engine)
+{
+ GEM_BUG_ON(!intel_engine_is_virtual(engine));
+ return container_of(engine, struct virtual_engine, base);
+}
+
+static int __execlists_context_alloc(struct intel_context *ce,
+ struct intel_engine_cs *engine);
+
+static void execlists_init_reg_state(u32 *reg_state,
+ const struct intel_context *ce,
+ const struct intel_engine_cs *engine,
+ const struct intel_ring *ring,
+ bool close);
+static void
+__execlists_update_reg_state(const struct intel_context *ce,
+ const struct intel_engine_cs *engine,
+ u32 head);
+
+static int lrc_ring_mi_mode(const struct intel_engine_cs *engine)
+{
+ if (INTEL_GEN(engine->i915) >= 12)
+ return 0x60;
+ else if (INTEL_GEN(engine->i915) >= 9)
+ return 0x54;
+ else if (engine->class == RENDER_CLASS)
+ return 0x58;
+ else
+ return -1;
+}
+
+static int lrc_ring_gpr0(const struct intel_engine_cs *engine)
+{
+ if (INTEL_GEN(engine->i915) >= 12)
+ return 0x74;
+ else if (INTEL_GEN(engine->i915) >= 9)
+ return 0x68;
+ else if (engine->class == RENDER_CLASS)
+ return 0xd8;
+ else
+ return -1;
+}
+
+static int lrc_ring_wa_bb_per_ctx(const struct intel_engine_cs *engine)
+{
+ if (INTEL_GEN(engine->i915) >= 12)
+ return 0x12;
+ else if (INTEL_GEN(engine->i915) >= 9 || engine->class == RENDER_CLASS)
+ return 0x18;
+ else
+ return -1;
+}
+
+static int lrc_ring_indirect_ptr(const struct intel_engine_cs *engine)
+{
+ int x;
+
+ x = lrc_ring_wa_bb_per_ctx(engine);
+ if (x < 0)
+ return x;
+
+ return x + 2;
+}
+
+static int lrc_ring_indirect_offset(const struct intel_engine_cs *engine)
+{
+ int x;
+
+ x = lrc_ring_indirect_ptr(engine);
+ if (x < 0)
+ return x;
+
+ return x + 2;
+}
+
+static int lrc_ring_cmd_buf_cctl(const struct intel_engine_cs *engine)
+{
+ if (engine->class != RENDER_CLASS)
+ return -1;
+
+ if (INTEL_GEN(engine->i915) >= 12)
+ return 0xb6;
+ else if (INTEL_GEN(engine->i915) >= 11)
+ return 0xaa;
+ else
+ return -1;
+}
+
+static u32
+lrc_ring_indirect_offset_default(const struct intel_engine_cs *engine)
+{
+ switch (INTEL_GEN(engine->i915)) {
+ default:
+ MISSING_CASE(INTEL_GEN(engine->i915));
+ fallthrough;
+ case 12:
+ return GEN12_CTX_RCS_INDIRECT_CTX_OFFSET_DEFAULT;
+ case 11:
+ return GEN11_CTX_RCS_INDIRECT_CTX_OFFSET_DEFAULT;
+ case 10:
+ return GEN10_CTX_RCS_INDIRECT_CTX_OFFSET_DEFAULT;
+ case 9:
+ return GEN9_CTX_RCS_INDIRECT_CTX_OFFSET_DEFAULT;
+ case 8:
+ return GEN8_CTX_RCS_INDIRECT_CTX_OFFSET_DEFAULT;
+ }
+}
+
+static void
+lrc_ring_setup_indirect_ctx(u32 *regs,
+ const struct intel_engine_cs *engine,
+ u32 ctx_bb_ggtt_addr,
+ u32 size)
+{
+ GEM_BUG_ON(!size);
+ GEM_BUG_ON(!IS_ALIGNED(size, CACHELINE_BYTES));
+ GEM_BUG_ON(lrc_ring_indirect_ptr(engine) == -1);
+ regs[lrc_ring_indirect_ptr(engine) + 1] =
+ ctx_bb_ggtt_addr | (size / CACHELINE_BYTES);
+
+ GEM_BUG_ON(lrc_ring_indirect_offset(engine) == -1);
+ regs[lrc_ring_indirect_offset(engine) + 1] =
+ lrc_ring_indirect_offset_default(engine) << 6;
+}
+
+static u32 intel_context_get_runtime(const struct intel_context *ce)
+{
+ /*
+ * We can use either ppHWSP[16] which is recorded before the context
+ * switch (and so excludes the cost of context switches) or use the
+ * value from the context image itself, which is saved/restored earlier
+ * and so includes the cost of the save.
+ */
+ return READ_ONCE(ce->lrc_reg_state[CTX_TIMESTAMP]);
+}
+
+static void mark_eio(struct i915_request *rq)
+{
+ if (i915_request_completed(rq))
+ return;
+
+ GEM_BUG_ON(i915_request_signaled(rq));
+
+ i915_request_set_error_once(rq, -EIO);
+ i915_request_mark_complete(rq);
+}
+
+static struct i915_request *
+active_request(const struct intel_timeline * const tl, struct i915_request *rq)
+{
+ struct i915_request *active = rq;
+
+ rcu_read_lock();
+ list_for_each_entry_continue_reverse(rq, &tl->requests, link) {
+ if (i915_request_completed(rq))
+ break;
+
+ active = rq;
+ }
+ rcu_read_unlock();
+
+ return active;
+}
+
+static inline u32 intel_hws_preempt_address(struct intel_engine_cs *engine)
+{
+ return (i915_ggtt_offset(engine->status_page.vma) +
+ I915_GEM_HWS_PREEMPT_ADDR);
+}
+
+static inline void
+ring_set_paused(const struct intel_engine_cs *engine, int state)
+{
+ /*
+ * We inspect HWS_PREEMPT with a semaphore inside
+ * engine->emit_fini_breadcrumb. If the dword is true,
+ * the ring is paused as the semaphore will busywait
+ * until the dword is false.
+ */
+ engine->status_page.addr[I915_GEM_HWS_PREEMPT] = state;
+ if (state)
+ wmb();
+}
+
+static inline struct i915_priolist *to_priolist(struct rb_node *rb)
+{
+ return rb_entry(rb, struct i915_priolist, node);
+}
+
+static inline int rq_prio(const struct i915_request *rq)
+{
+ return READ_ONCE(rq->sched.attr.priority);
+}
+
+static int effective_prio(const struct i915_request *rq)
+{
+ int prio = rq_prio(rq);
+
+ /*
+ * If this request is special and must not be interrupted at any
+ * cost, so be it. Note we are only checking the most recent request
+ * in the context and so may be masking an earlier vip request. It
+ * is hoped that under the conditions where nopreempt is used, this
+ * will not matter (i.e. all requests to that context will be
+ * nopreempt for as long as desired).
+ */
+ if (i915_request_has_nopreempt(rq))
+ prio = I915_PRIORITY_UNPREEMPTABLE;
+
+ return prio;
+}
+
+static int queue_prio(const struct intel_engine_execlists *execlists)
+{
+ struct i915_priolist *p;
+ struct rb_node *rb;
+
+ rb = rb_first_cached(&execlists->queue);
+ if (!rb)
+ return INT_MIN;
+
+ /*
+ * As the priolist[] are inverted, with the highest priority in [0],
+ * we have to flip the index value to become priority.
+ */
+ p = to_priolist(rb);
+ if (!I915_USER_PRIORITY_SHIFT)
+ return p->priority;
+
+ return ((p->priority + 1) << I915_USER_PRIORITY_SHIFT) - ffs(p->used);
+}
+
+static inline bool need_preempt(const struct intel_engine_cs *engine,
+ const struct i915_request *rq,
+ struct rb_node *rb)
+{
+ int last_prio;
+
+ if (!intel_engine_has_semaphores(engine))
+ return false;
+
+ /*
+ * Check if the current priority hint merits a preemption attempt.
+ *
+ * We record the highest value priority we saw during rescheduling
+ * prior to this dequeue, therefore we know that if it is strictly
+ * less than the current tail of ESLP[0], we do not need to force
+ * a preempt-to-idle cycle.
+ *
+ * However, the priority hint is a mere hint that we may need to
+ * preempt. If that hint is stale or we may be trying to preempt
+ * ourselves, ignore the request.
+ *
+ * More naturally we would write
+ * prio >= max(0, last);
+ * except that we wish to prevent triggering preemption at the same
+ * priority level: the task that is running should remain running
+ * to preserve FIFO ordering of dependencies.
+ */
+ last_prio = max(effective_prio(rq), I915_PRIORITY_NORMAL - 1);
+ if (engine->execlists.queue_priority_hint <= last_prio)
+ return false;
+
+ /*
+ * Check against the first request in ELSP[1], it will, thanks to the
+ * power of PI, be the highest priority of that context.
+ */
+ if (!list_is_last(&rq->sched.link, &engine->active.requests) &&
+ rq_prio(list_next_entry(rq, sched.link)) > last_prio)
+ return true;
+
+ if (rb) {
+ struct virtual_engine *ve =
+ rb_entry(rb, typeof(*ve), nodes[engine->id].rb);
+ bool preempt = false;
+
+ if (engine == ve->siblings[0]) { /* only preempt one sibling */
+ struct i915_request *next;
+
+ rcu_read_lock();
+ next = READ_ONCE(ve->request);
+ if (next)
+ preempt = rq_prio(next) > last_prio;
+ rcu_read_unlock();
+ }
+
+ if (preempt)
+ return preempt;
+ }
+
+ /*
+ * If the inflight context did not trigger the preemption, then maybe
+ * it was the set of queued requests? Pick the highest priority in
+ * the queue (the first active priolist) and see if it deserves to be
+ * running instead of ELSP[0].
+ *
+ * The highest priority request in the queue can not be either
+ * ELSP[0] or ELSP[1] as, thanks again to PI, if it was the same
+ * context, it's priority would not exceed ELSP[0] aka last_prio.
+ */
+ return queue_prio(&engine->execlists) > last_prio;
+}
+
+__maybe_unused static inline bool
+assert_priority_queue(const struct i915_request *prev,
+ const struct i915_request *next)
+{
+ /*
+ * Without preemption, the prev may refer to the still active element
+ * which we refuse to let go.
+ *
+ * Even with preemption, there are times when we think it is better not
+ * to preempt and leave an ostensibly lower priority request in flight.
+ */
+ if (i915_request_is_active(prev))
+ return true;
+
+ return rq_prio(prev) >= rq_prio(next);
+}
+
+/*
+ * The context descriptor encodes various attributes of a context,
+ * including its GTT address and some flags. Because it's fairly
+ * expensive to calculate, we'll just do it once and cache the result,
+ * which remains valid until the context is unpinned.
+ *
+ * This is what a descriptor looks like, from LSB to MSB::
+ *
+ * bits 0-11: flags, GEN8_CTX_* (cached in ctx->desc_template)
+ * bits 12-31: LRCA, GTT address of (the HWSP of) this context
+ * bits 32-52: ctx ID, a globally unique tag (highest bit used by GuC)
+ * bits 53-54: mbz, reserved for use by hardware
+ * bits 55-63: group ID, currently unused and set to 0
+ *
+ * Starting from Gen11, the upper dword of the descriptor has a new format:
+ *
+ * bits 32-36: reserved
+ * bits 37-47: SW context ID
+ * bits 48:53: engine instance
+ * bit 54: mbz, reserved for use by hardware
+ * bits 55-60: SW counter
+ * bits 61-63: engine class
+ *
+ * engine info, SW context ID and SW counter need to form a unique number
+ * (Context ID) per lrc.
+ */
+static u32
+lrc_descriptor(struct intel_context *ce, struct intel_engine_cs *engine)
+{
+ u32 desc;
+
+ desc = INTEL_LEGACY_32B_CONTEXT;
+ if (i915_vm_is_4lvl(ce->vm))
+ desc = INTEL_LEGACY_64B_CONTEXT;
+ desc <<= GEN8_CTX_ADDRESSING_MODE_SHIFT;
+
+ desc |= GEN8_CTX_VALID | GEN8_CTX_PRIVILEGE;
+ if (IS_GEN(engine->i915, 8))
+ desc |= GEN8_CTX_L3LLC_COHERENT;
+
+ return i915_ggtt_offset(ce->state) | desc;
+}
+
+static inline unsigned int dword_in_page(void *addr)
+{
+ return offset_in_page(addr) / sizeof(u32);
+}
+
+static void set_offsets(u32 *regs,
+ const u8 *data,
+ const struct intel_engine_cs *engine,
+ bool clear)
+#define NOP(x) (BIT(7) | (x))
+#define LRI(count, flags) ((flags) << 6 | (count) | BUILD_BUG_ON_ZERO(count >= BIT(6)))
+#define POSTED BIT(0)
+#define REG(x) (((x) >> 2) | BUILD_BUG_ON_ZERO(x >= 0x200))
+#define REG16(x) \
+ (((x) >> 9) | BIT(7) | BUILD_BUG_ON_ZERO(x >= 0x10000)), \
+ (((x) >> 2) & 0x7f)
+#define END(total_state_size) 0, (total_state_size)
+{
+ const u32 base = engine->mmio_base;
+
+ while (*data) {
+ u8 count, flags;
+
+ if (*data & BIT(7)) { /* skip */
+ count = *data++ & ~BIT(7);
+ if (clear)
+ memset32(regs, MI_NOOP, count);
+ regs += count;
+ continue;
+ }
+
+ count = *data & 0x3f;
+ flags = *data >> 6;
+ data++;
+
+ *regs = MI_LOAD_REGISTER_IMM(count);
+ if (flags & POSTED)
+ *regs |= MI_LRI_FORCE_POSTED;
+ if (INTEL_GEN(engine->i915) >= 11)
+ *regs |= MI_LRI_LRM_CS_MMIO;
+ regs++;
+
+ GEM_BUG_ON(!count);
+ do {
+ u32 offset = 0;
+ u8 v;
+
+ do {
+ v = *data++;
+ offset <<= 7;
+ offset |= v & ~BIT(7);
+ } while (v & BIT(7));
+
+ regs[0] = base + (offset << 2);
+ if (clear)
+ regs[1] = 0;
+ regs += 2;
+ } while (--count);
+ }
+
+ if (clear) {
+ u8 count = *++data;
+
+ /* Clear past the tail for HW access */
+ GEM_BUG_ON(dword_in_page(regs) > count);
+ memset32(regs, MI_NOOP, count - dword_in_page(regs));
+
+ /* Close the batch; used mainly by live_lrc_layout() */
+ *regs = MI_BATCH_BUFFER_END;
+ if (INTEL_GEN(engine->i915) >= 10)
+ *regs |= BIT(0);
+ }
+}
+
+static const u8 gen8_xcs_offsets[] = {
+ NOP(1),
+ LRI(11, 0),
+ REG16(0x244),
+ REG(0x034),
+ REG(0x030),
+ REG(0x038),
+ REG(0x03c),
+ REG(0x168),
+ REG(0x140),
+ REG(0x110),
+ REG(0x11c),
+ REG(0x114),
+ REG(0x118),
+
+ NOP(9),
+ LRI(9, 0),
+ REG16(0x3a8),
+ REG16(0x28c),
+ REG16(0x288),
+ REG16(0x284),
+ REG16(0x280),
+ REG16(0x27c),
+ REG16(0x278),
+ REG16(0x274),
+ REG16(0x270),
+
+ NOP(13),
+ LRI(2, 0),
+ REG16(0x200),
+ REG(0x028),
+
+ END(80)
+};
+
+static const u8 gen9_xcs_offsets[] = {
+ NOP(1),
+ LRI(14, POSTED),
+ REG16(0x244),
+ REG(0x034),
+ REG(0x030),
+ REG(0x038),
+ REG(0x03c),
+ REG(0x168),
+ REG(0x140),
+ REG(0x110),
+ REG(0x11c),
+ REG(0x114),
+ REG(0x118),
+ REG(0x1c0),
+ REG(0x1c4),
+ REG(0x1c8),
+
+ NOP(3),
+ LRI(9, POSTED),
+ REG16(0x3a8),
+ REG16(0x28c),
+ REG16(0x288),
+ REG16(0x284),
+ REG16(0x280),
+ REG16(0x27c),
+ REG16(0x278),
+ REG16(0x274),
+ REG16(0x270),
+
+ NOP(13),
+ LRI(1, POSTED),
+ REG16(0x200),
+
+ NOP(13),
+ LRI(44, POSTED),
+ REG(0x028),
+ REG(0x09c),
+ REG(0x0c0),
+ REG(0x178),
+ REG(0x17c),
+ REG16(0x358),
+ REG(0x170),
+ REG(0x150),
+ REG(0x154),
+ REG(0x158),
+ REG16(0x41c),
+ REG16(0x600),
+ REG16(0x604),
+ REG16(0x608),
+ REG16(0x60c),
+ REG16(0x610),
+ REG16(0x614),
+ REG16(0x618),
+ REG16(0x61c),
+ REG16(0x620),
+ REG16(0x624),
+ REG16(0x628),
+ REG16(0x62c),
+ REG16(0x630),
+ REG16(0x634),
+ REG16(0x638),
+ REG16(0x63c),
+ REG16(0x640),
+ REG16(0x644),
+ REG16(0x648),
+ REG16(0x64c),
+ REG16(0x650),
+ REG16(0x654),
+ REG16(0x658),
+ REG16(0x65c),
+ REG16(0x660),
+ REG16(0x664),
+ REG16(0x668),
+ REG16(0x66c),
+ REG16(0x670),
+ REG16(0x674),
+ REG16(0x678),
+ REG16(0x67c),
+ REG(0x068),
+
+ END(176)
+};
+
+static const u8 gen12_xcs_offsets[] = {
+ NOP(1),
+ LRI(13, POSTED),
+ REG16(0x244),
+ REG(0x034),
+ REG(0x030),
+ REG(0x038),
+ REG(0x03c),
+ REG(0x168),
+ REG(0x140),
+ REG(0x110),
+ REG(0x1c0),
+ REG(0x1c4),
+ REG(0x1c8),
+ REG(0x180),
+ REG16(0x2b4),
+
+ NOP(5),
+ LRI(9, POSTED),
+ REG16(0x3a8),
+ REG16(0x28c),
+ REG16(0x288),
+ REG16(0x284),
+ REG16(0x280),
+ REG16(0x27c),
+ REG16(0x278),
+ REG16(0x274),
+ REG16(0x270),
+
+ END(80)
+};
+
+static const u8 gen8_rcs_offsets[] = {
+ NOP(1),
+ LRI(14, POSTED),
+ REG16(0x244),
+ REG(0x034),
+ REG(0x030),
+ REG(0x038),
+ REG(0x03c),
+ REG(0x168),
+ REG(0x140),
+ REG(0x110),
+ REG(0x11c),
+ REG(0x114),
+ REG(0x118),
+ REG(0x1c0),
+ REG(0x1c4),
+ REG(0x1c8),
+
+ NOP(3),
+ LRI(9, POSTED),
+ REG16(0x3a8),
+ REG16(0x28c),
+ REG16(0x288),
+ REG16(0x284),
+ REG16(0x280),
+ REG16(0x27c),
+ REG16(0x278),
+ REG16(0x274),
+ REG16(0x270),
+
+ NOP(13),
+ LRI(1, 0),
+ REG(0x0c8),
+
+ END(80)
+};
+
+static const u8 gen9_rcs_offsets[] = {
+ NOP(1),
+ LRI(14, POSTED),
+ REG16(0x244),
+ REG(0x34),
+ REG(0x30),
+ REG(0x38),
+ REG(0x3c),
+ REG(0x168),
+ REG(0x140),
+ REG(0x110),
+ REG(0x11c),
+ REG(0x114),
+ REG(0x118),
+ REG(0x1c0),
+ REG(0x1c4),
+ REG(0x1c8),
+
+ NOP(3),
+ LRI(9, POSTED),
+ REG16(0x3a8),
+ REG16(0x28c),
+ REG16(0x288),
+ REG16(0x284),
+ REG16(0x280),
+ REG16(0x27c),
+ REG16(0x278),
+ REG16(0x274),
+ REG16(0x270),
+
+ NOP(13),
+ LRI(1, 0),
+ REG(0xc8),
+
+ NOP(13),
+ LRI(44, POSTED),
+ REG(0x28),
+ REG(0x9c),
+ REG(0xc0),
+ REG(0x178),
+ REG(0x17c),
+ REG16(0x358),
+ REG(0x170),
+ REG(0x150),
+ REG(0x154),
+ REG(0x158),
+ REG16(0x41c),
+ REG16(0x600),
+ REG16(0x604),
+ REG16(0x608),
+ REG16(0x60c),
+ REG16(0x610),
+ REG16(0x614),
+ REG16(0x618),
+ REG16(0x61c),
+ REG16(0x620),
+ REG16(0x624),
+ REG16(0x628),
+ REG16(0x62c),
+ REG16(0x630),
+ REG16(0x634),
+ REG16(0x638),
+ REG16(0x63c),
+ REG16(0x640),
+ REG16(0x644),
+ REG16(0x648),
+ REG16(0x64c),
+ REG16(0x650),
+ REG16(0x654),
+ REG16(0x658),
+ REG16(0x65c),
+ REG16(0x660),
+ REG16(0x664),
+ REG16(0x668),
+ REG16(0x66c),
+ REG16(0x670),
+ REG16(0x674),
+ REG16(0x678),
+ REG16(0x67c),
+ REG(0x68),
+
+ END(176)
+};
+
+static const u8 gen11_rcs_offsets[] = {
+ NOP(1),
+ LRI(15, POSTED),
+ REG16(0x244),
+ REG(0x034),
+ REG(0x030),
+ REG(0x038),
+ REG(0x03c),
+ REG(0x168),
+ REG(0x140),
+ REG(0x110),
+ REG(0x11c),
+ REG(0x114),
+ REG(0x118),
+ REG(0x1c0),
+ REG(0x1c4),
+ REG(0x1c8),
+ REG(0x180),
+
+ NOP(1),
+ LRI(9, POSTED),
+ REG16(0x3a8),
+ REG16(0x28c),
+ REG16(0x288),
+ REG16(0x284),
+ REG16(0x280),
+ REG16(0x27c),
+ REG16(0x278),
+ REG16(0x274),
+ REG16(0x270),
+
+ LRI(1, POSTED),
+ REG(0x1b0),
+
+ NOP(10),
+ LRI(1, 0),
+ REG(0x0c8),
+
+ END(80)
+};
+
+static const u8 gen12_rcs_offsets[] = {
+ NOP(1),
+ LRI(13, POSTED),
+ REG16(0x244),
+ REG(0x034),
+ REG(0x030),
+ REG(0x038),
+ REG(0x03c),
+ REG(0x168),
+ REG(0x140),
+ REG(0x110),
+ REG(0x1c0),
+ REG(0x1c4),
+ REG(0x1c8),
+ REG(0x180),
+ REG16(0x2b4),
+
+ NOP(5),
+ LRI(9, POSTED),
+ REG16(0x3a8),
+ REG16(0x28c),
+ REG16(0x288),
+ REG16(0x284),
+ REG16(0x280),
+ REG16(0x27c),
+ REG16(0x278),
+ REG16(0x274),
+ REG16(0x270),
+
+ LRI(3, POSTED),
+ REG(0x1b0),
+ REG16(0x5a8),
+ REG16(0x5ac),
+
+ NOP(6),
+ LRI(1, 0),
+ REG(0x0c8),
+ NOP(3 + 9 + 1),
+
+ LRI(51, POSTED),
+ REG16(0x588),
+ REG16(0x588),
+ REG16(0x588),
+ REG16(0x588),
+ REG16(0x588),
+ REG16(0x588),
+ REG(0x028),
+ REG(0x09c),
+ REG(0x0c0),
+ REG(0x178),
+ REG(0x17c),
+ REG16(0x358),
+ REG(0x170),
+ REG(0x150),
+ REG(0x154),
+ REG(0x158),
+ REG16(0x41c),
+ REG16(0x600),
+ REG16(0x604),
+ REG16(0x608),
+ REG16(0x60c),
+ REG16(0x610),
+ REG16(0x614),
+ REG16(0x618),
+ REG16(0x61c),
+ REG16(0x620),
+ REG16(0x624),
+ REG16(0x628),
+ REG16(0x62c),
+ REG16(0x630),
+ REG16(0x634),
+ REG16(0x638),
+ REG16(0x63c),
+ REG16(0x640),
+ REG16(0x644),
+ REG16(0x648),
+ REG16(0x64c),
+ REG16(0x650),
+ REG16(0x654),
+ REG16(0x658),
+ REG16(0x65c),
+ REG16(0x660),
+ REG16(0x664),
+ REG16(0x668),
+ REG16(0x66c),
+ REG16(0x670),
+ REG16(0x674),
+ REG16(0x678),
+ REG16(0x67c),
+ REG(0x068),
+ REG(0x084),
+ NOP(1),
+
+ END(192)
+};
+
+#undef END
+#undef REG16
+#undef REG
+#undef LRI
+#undef NOP
+
+static const u8 *reg_offsets(const struct intel_engine_cs *engine)
+{
+ /*
+ * The gen12+ lists only have the registers we program in the basic
+ * default state. We rely on the context image using relative
+ * addressing to automatic fixup the register state between the
+ * physical engines for virtual engine.
+ */
+ GEM_BUG_ON(INTEL_GEN(engine->i915) >= 12 &&
+ !intel_engine_has_relative_mmio(engine));
+
+ if (engine->class == RENDER_CLASS) {
+ if (INTEL_GEN(engine->i915) >= 12)
+ return gen12_rcs_offsets;
+ else if (INTEL_GEN(engine->i915) >= 11)
+ return gen11_rcs_offsets;
+ else if (INTEL_GEN(engine->i915) >= 9)
+ return gen9_rcs_offsets;
+ else
+ return gen8_rcs_offsets;
+ } else {
+ if (INTEL_GEN(engine->i915) >= 12)
+ return gen12_xcs_offsets;
+ else if (INTEL_GEN(engine->i915) >= 9)
+ return gen9_xcs_offsets;
+ else
+ return gen8_xcs_offsets;
+ }
+}
+
+static struct i915_request *
+__unwind_incomplete_requests(struct intel_engine_cs *engine)
+{
+ struct i915_request *rq, *rn, *active = NULL;
+ struct list_head *pl;
+ int prio = I915_PRIORITY_INVALID;
+
+ lockdep_assert_held(&engine->active.lock);
+
+ list_for_each_entry_safe_reverse(rq, rn,
+ &engine->active.requests,
+ sched.link) {
+ if (i915_request_completed(rq)) {
+ list_del_init(&rq->sched.link);
+ continue;
+ }
+
+ __i915_request_unsubmit(rq);
+
+ /*
+ * Push the request back into the queue for later resubmission.
+ * If this request is not native to this physical engine (i.e.
+ * it came from a virtual source), push it back onto the virtual
+ * engine so that it can be moved across onto another physical
+ * engine as load dictates.
+ */
+ if (likely(rq->execution_mask == engine->mask)) {
+ GEM_BUG_ON(rq_prio(rq) == I915_PRIORITY_INVALID);
+ if (rq_prio(rq) != prio) {
+ prio = rq_prio(rq);
+ pl = i915_sched_lookup_priolist(engine, prio);
+ }
+ GEM_BUG_ON(RB_EMPTY_ROOT(&engine->execlists.queue.rb_root));
+
+ list_move(&rq->sched.link, pl);
+ set_bit(I915_FENCE_FLAG_PQUEUE, &rq->fence.flags);
+
+ /* Check in case we rollback so far we wrap [size/2] */
+ if (intel_ring_direction(rq->ring,
+ rq->tail,
+ rq->ring->tail + 8) > 0)
+ rq->context->lrc.desc |= CTX_DESC_FORCE_RESTORE;
+
+ active = rq;
+ } else {
+ struct intel_engine_cs *owner = rq->context->engine;
+
+ WRITE_ONCE(rq->engine, owner);
+ owner->submit_request(rq);
+ active = NULL;
+ }
+ }
+
+ return active;
+}
+
+struct i915_request *
+execlists_unwind_incomplete_requests(struct intel_engine_execlists *execlists)
+{
+ struct intel_engine_cs *engine =
+ container_of(execlists, typeof(*engine), execlists);
+
+ return __unwind_incomplete_requests(engine);
+}
+
+static inline void
+execlists_context_status_change(struct i915_request *rq, unsigned long status)
+{
+ /*
+ * Only used when GVT-g is enabled now. When GVT-g is disabled,
+ * The compiler should eliminate this function as dead-code.
+ */
+ if (!IS_ENABLED(CONFIG_DRM_I915_GVT))
+ return;
+
+ atomic_notifier_call_chain(&rq->engine->context_status_notifier,
+ status, rq);
+}
+
+static void intel_engine_context_in(struct intel_engine_cs *engine)
+{
+ unsigned long flags;
+
+ if (atomic_add_unless(&engine->stats.active, 1, 0))
+ return;
+
+ write_seqlock_irqsave(&engine->stats.lock, flags);
+ if (!atomic_add_unless(&engine->stats.active, 1, 0)) {
+ engine->stats.start = ktime_get();
+ atomic_inc(&engine->stats.active);
+ }
+ write_sequnlock_irqrestore(&engine->stats.lock, flags);
+}
+
+static void intel_engine_context_out(struct intel_engine_cs *engine)
+{
+ unsigned long flags;
+
+ GEM_BUG_ON(!atomic_read(&engine->stats.active));
+
+ if (atomic_add_unless(&engine->stats.active, -1, 1))
+ return;
+
+ write_seqlock_irqsave(&engine->stats.lock, flags);
+ if (atomic_dec_and_test(&engine->stats.active)) {
+ engine->stats.total =
+ ktime_add(engine->stats.total,
+ ktime_sub(ktime_get(), engine->stats.start));
+ }
+ write_sequnlock_irqrestore(&engine->stats.lock, flags);
+}
+
+static void
+execlists_check_context(const struct intel_context *ce,
+ const struct intel_engine_cs *engine,
+ const char *when)
+{
+ const struct intel_ring *ring = ce->ring;
+ u32 *regs = ce->lrc_reg_state;
+ bool valid = true;
+ int x;
+
+ if (regs[CTX_RING_START] != i915_ggtt_offset(ring->vma)) {
+ pr_err("%s: context submitted with incorrect RING_START [%08x], expected %08x\n",
+ engine->name,
+ regs[CTX_RING_START],
+ i915_ggtt_offset(ring->vma));
+ regs[CTX_RING_START] = i915_ggtt_offset(ring->vma);
+ valid = false;
+ }
+
+ if ((regs[CTX_RING_CTL] & ~(RING_WAIT | RING_WAIT_SEMAPHORE)) !=
+ (RING_CTL_SIZE(ring->size) | RING_VALID)) {
+ pr_err("%s: context submitted with incorrect RING_CTL [%08x], expected %08x\n",
+ engine->name,
+ regs[CTX_RING_CTL],
+ (u32)(RING_CTL_SIZE(ring->size) | RING_VALID));
+ regs[CTX_RING_CTL] = RING_CTL_SIZE(ring->size) | RING_VALID;
+ valid = false;
+ }
+
+ x = lrc_ring_mi_mode(engine);
+ if (x != -1 && regs[x + 1] & (regs[x + 1] >> 16) & STOP_RING) {
+ pr_err("%s: context submitted with STOP_RING [%08x] in RING_MI_MODE\n",
+ engine->name, regs[x + 1]);
+ regs[x + 1] &= ~STOP_RING;
+ regs[x + 1] |= STOP_RING << 16;
+ valid = false;
+ }
+
+ WARN_ONCE(!valid, "Invalid lrc state found %s submission\n", when);
+}
+
+static void restore_default_state(struct intel_context *ce,
+ struct intel_engine_cs *engine)
+{
+ u32 *regs;
+
+ regs = memset(ce->lrc_reg_state, 0, engine->context_size - PAGE_SIZE);
+ execlists_init_reg_state(regs, ce, engine, ce->ring, true);
+
+ ce->runtime.last = intel_context_get_runtime(ce);
+}
+
+static void reset_active(struct i915_request *rq,
+ struct intel_engine_cs *engine)
+{
+ struct intel_context * const ce = rq->context;
+ u32 head;
+
+ /*
+ * The executing context has been cancelled. We want to prevent
+ * further execution along this context and propagate the error on
+ * to anything depending on its results.
+ *
+ * In __i915_request_submit(), we apply the -EIO and remove the
+ * requests' payloads for any banned requests. But first, we must
+ * rewind the context back to the start of the incomplete request so
+ * that we do not jump back into the middle of the batch.
+ *
+ * We preserve the breadcrumbs and semaphores of the incomplete
+ * requests so that inter-timeline dependencies (i.e other timelines)
+ * remain correctly ordered. And we defer to __i915_request_submit()
+ * so that all asynchronous waits are correctly handled.
+ */
+ ENGINE_TRACE(engine, "{ rq=%llx:%lld }\n",
+ rq->fence.context, rq->fence.seqno);
+
+ /* On resubmission of the active request, payload will be scrubbed */
+ if (i915_request_completed(rq))
+ head = rq->tail;
+ else
+ head = active_request(ce->timeline, rq)->head;
+ head = intel_ring_wrap(ce->ring, head);
+
+ /* Scrub the context image to prevent replaying the previous batch */
+ restore_default_state(ce, engine);
+ __execlists_update_reg_state(ce, engine, head);
+
+ /* We've switched away, so this should be a no-op, but intent matters */
+ ce->lrc.desc |= CTX_DESC_FORCE_RESTORE;
+}
+
+static void st_update_runtime_underflow(struct intel_context *ce, s32 dt)
+{
+#if IS_ENABLED(CONFIG_DRM_I915_SELFTEST)
+ ce->runtime.num_underflow++;
+ ce->runtime.max_underflow = max_t(u32, ce->runtime.max_underflow, -dt);
+#endif
+}
+
+static void intel_context_update_runtime(struct intel_context *ce)
+{
+ u32 old;
+ s32 dt;
+
+ if (intel_context_is_barrier(ce))
+ return;
+
+ old = ce->runtime.last;
+ ce->runtime.last = intel_context_get_runtime(ce);
+ dt = ce->runtime.last - old;
+
+ if (unlikely(dt < 0)) {
+ CE_TRACE(ce, "runtime underflow: last=%u, new=%u, delta=%d\n",
+ old, ce->runtime.last, dt);
+ st_update_runtime_underflow(ce, dt);
+ return;
+ }
+
+ ewma_runtime_add(&ce->runtime.avg, dt);
+ ce->runtime.total += dt;
+}
+
+static inline struct intel_engine_cs *
+__execlists_schedule_in(struct i915_request *rq)
+{
+ struct intel_engine_cs * const engine = rq->engine;
+ struct intel_context * const ce = rq->context;
+
+ intel_context_get(ce);
+
+ if (unlikely(intel_context_is_banned(ce)))
+ reset_active(rq, engine);
+
+ if (IS_ENABLED(CONFIG_DRM_I915_DEBUG_GEM))
+ execlists_check_context(ce, engine, "before");
+
+ if (ce->tag) {
+ /* Use a fixed tag for OA and friends */
+ GEM_BUG_ON(ce->tag <= BITS_PER_LONG);
+ ce->lrc.ccid = ce->tag;
+ } else {
+ /* We don't need a strict matching tag, just different values */
+ unsigned int tag = ffs(READ_ONCE(engine->context_tag));
+
+ GEM_BUG_ON(tag == 0 || tag >= BITS_PER_LONG);
+ clear_bit(tag - 1, &engine->context_tag);
+ ce->lrc.ccid = tag << (GEN11_SW_CTX_ID_SHIFT - 32);
+
+ BUILD_BUG_ON(BITS_PER_LONG > GEN12_MAX_CONTEXT_HW_ID);
+ }
+
+ ce->lrc.ccid |= engine->execlists.ccid;
+
+ __intel_gt_pm_get(engine->gt);
+ if (engine->fw_domain && !atomic_fetch_inc(&engine->fw_active))
+ intel_uncore_forcewake_get(engine->uncore, engine->fw_domain);
+ execlists_context_status_change(rq, INTEL_CONTEXT_SCHEDULE_IN);
+ intel_engine_context_in(engine);
+
+ return engine;
+}
+
+static inline struct i915_request *
+execlists_schedule_in(struct i915_request *rq, int idx)
+{
+ struct intel_context * const ce = rq->context;
+ struct intel_engine_cs *old;
+
+ GEM_BUG_ON(!intel_engine_pm_is_awake(rq->engine));
+ trace_i915_request_in(rq, idx);
+
+ old = READ_ONCE(ce->inflight);
+ do {
+ if (!old) {
+ WRITE_ONCE(ce->inflight, __execlists_schedule_in(rq));
+ break;
+ }
+ } while (!try_cmpxchg(&ce->inflight, &old, ptr_inc(old)));
+
+ GEM_BUG_ON(intel_context_inflight(ce) != rq->engine);
+ return i915_request_get(rq);
+}
+
+static void kick_siblings(struct i915_request *rq, struct intel_context *ce)
+{
+ struct virtual_engine *ve = container_of(ce, typeof(*ve), context);
+ struct i915_request *next = READ_ONCE(ve->request);
+
+ if (next == rq || (next && next->execution_mask & ~rq->execution_mask))
+ tasklet_hi_schedule(&ve->base.execlists.tasklet);
+}
+
+static inline void
+__execlists_schedule_out(struct i915_request *rq,
+ struct intel_engine_cs * const engine,
+ unsigned int ccid)
+{
+ struct intel_context * const ce = rq->context;
+
+ /*
+ * NB process_csb() is not under the engine->active.lock and hence
+ * schedule_out can race with schedule_in meaning that we should
+ * refrain from doing non-trivial work here.
+ */
+
+ if (IS_ENABLED(CONFIG_DRM_I915_DEBUG_GEM))
+ execlists_check_context(ce, engine, "after");
+
+ /*
+ * If we have just completed this context, the engine may now be
+ * idle and we want to re-enter powersaving.
+ */
+ if (list_is_last_rcu(&rq->link, &ce->timeline->requests) &&
+ i915_request_completed(rq))
+ intel_engine_add_retire(engine, ce->timeline);
+
+ ccid >>= GEN11_SW_CTX_ID_SHIFT - 32;
+ ccid &= GEN12_MAX_CONTEXT_HW_ID;
+ if (ccid < BITS_PER_LONG) {
+ GEM_BUG_ON(ccid == 0);
+ GEM_BUG_ON(test_bit(ccid - 1, &engine->context_tag));
+ set_bit(ccid - 1, &engine->context_tag);
+ }
+
+ intel_context_update_runtime(ce);
+ intel_engine_context_out(engine);
+ execlists_context_status_change(rq, INTEL_CONTEXT_SCHEDULE_OUT);
+ if (engine->fw_domain && !atomic_dec_return(&engine->fw_active))
+ intel_uncore_forcewake_put(engine->uncore, engine->fw_domain);
+ intel_gt_pm_put_async(engine->gt);
+
+ /*
+ * If this is part of a virtual engine, its next request may
+ * have been blocked waiting for access to the active context.
+ * We have to kick all the siblings again in case we need to
+ * switch (e.g. the next request is not runnable on this
+ * engine). Hopefully, we will already have submitted the next
+ * request before the tasklet runs and do not need to rebuild
+ * each virtual tree and kick everyone again.
+ */
+ if (ce->engine != engine)
+ kick_siblings(rq, ce);
+
+ intel_context_put(ce);
+}
+
+static inline void
+execlists_schedule_out(struct i915_request *rq)
+{
+ struct intel_context * const ce = rq->context;
+ struct intel_engine_cs *cur, *old;
+ u32 ccid;
+
+ trace_i915_request_out(rq);
+
+ ccid = rq->context->lrc.ccid;
+ old = READ_ONCE(ce->inflight);
+ do
+ cur = ptr_unmask_bits(old, 2) ? ptr_dec(old) : NULL;
+ while (!try_cmpxchg(&ce->inflight, &old, cur));
+ if (!cur)
+ __execlists_schedule_out(rq, old, ccid);
+
+ i915_request_put(rq);
+}
+
+static u64 execlists_update_context(struct i915_request *rq)
+{
+ struct intel_context *ce = rq->context;
+ u64 desc = ce->lrc.desc;
+ u32 tail, prev;
+
+ /*
+ * WaIdleLiteRestore:bdw,skl
+ *
+ * We should never submit the context with the same RING_TAIL twice
+ * just in case we submit an empty ring, which confuses the HW.
+ *
+ * We append a couple of NOOPs (gen8_emit_wa_tail) after the end of
+ * the normal request to be able to always advance the RING_TAIL on
+ * subsequent resubmissions (for lite restore). Should that fail us,
+ * and we try and submit the same tail again, force the context
+ * reload.
+ *
+ * If we need to return to a preempted context, we need to skip the
+ * lite-restore and force it to reload the RING_TAIL. Otherwise, the
+ * HW has a tendency to ignore us rewinding the TAIL to the end of
+ * an earlier request.
+ */
+ GEM_BUG_ON(ce->lrc_reg_state[CTX_RING_TAIL] != rq->ring->tail);
+ prev = rq->ring->tail;
+ tail = intel_ring_set_tail(rq->ring, rq->tail);
+ if (unlikely(intel_ring_direction(rq->ring, tail, prev) <= 0))
+ desc |= CTX_DESC_FORCE_RESTORE;
+ ce->lrc_reg_state[CTX_RING_TAIL] = tail;
+ rq->tail = rq->wa_tail;
+
+ /*
+ * Make sure the context image is complete before we submit it to HW.
+ *
+ * Ostensibly, writes (including the WCB) should be flushed prior to
+ * an uncached write such as our mmio register access, the empirical
+ * evidence (esp. on Braswell) suggests that the WC write into memory
+ * may not be visible to the HW prior to the completion of the UC
+ * register write and that we may begin execution from the context
+ * before its image is complete leading to invalid PD chasing.
+ */
+ wmb();
+
+ ce->lrc.desc &= ~CTX_DESC_FORCE_RESTORE;
+ return desc;
+}
+
+static inline void write_desc(struct intel_engine_execlists *execlists, u64 desc, u32 port)
+{
+ if (execlists->ctrl_reg) {
+ writel(lower_32_bits(desc), execlists->submit_reg + port * 2);
+ writel(upper_32_bits(desc), execlists->submit_reg + port * 2 + 1);
+ } else {
+ writel(upper_32_bits(desc), execlists->submit_reg);
+ writel(lower_32_bits(desc), execlists->submit_reg);
+ }
+}
+
+static __maybe_unused char *
+dump_port(char *buf, int buflen, const char *prefix, struct i915_request *rq)
+{
+ if (!rq)
+ return "";
+
+ snprintf(buf, buflen, "%sccid:%x %llx:%lld%s prio %d",
+ prefix,
+ rq->context->lrc.ccid,
+ rq->fence.context, rq->fence.seqno,
+ i915_request_completed(rq) ? "!" :
+ i915_request_started(rq) ? "*" :
+ "",
+ rq_prio(rq));
+
+ return buf;
+}
+
+static __maybe_unused void
+trace_ports(const struct intel_engine_execlists *execlists,
+ const char *msg,
+ struct i915_request * const *ports)
+{
+ const struct intel_engine_cs *engine =
+ container_of(execlists, typeof(*engine), execlists);
+ char __maybe_unused p0[40], p1[40];
+
+ if (!ports[0])
+ return;
+
+ ENGINE_TRACE(engine, "%s { %s%s }\n", msg,
+ dump_port(p0, sizeof(p0), "", ports[0]),
+ dump_port(p1, sizeof(p1), ", ", ports[1]));
+}
+
+static inline bool
+reset_in_progress(const struct intel_engine_execlists *execlists)
+{
+ return unlikely(!__tasklet_is_enabled(&execlists->tasklet));
+}
+
+static __maybe_unused bool
+assert_pending_valid(const struct intel_engine_execlists *execlists,
+ const char *msg)
+{
+ struct intel_engine_cs *engine =
+ container_of(execlists, typeof(*engine), execlists);
+ struct i915_request * const *port, *rq;
+ struct intel_context *ce = NULL;
+ bool sentinel = false;
+ u32 ccid = -1;
+
+ trace_ports(execlists, msg, execlists->pending);
+
+ /* We may be messing around with the lists during reset, lalala */
+ if (reset_in_progress(execlists))
+ return true;
+
+ if (!execlists->pending[0]) {
+ GEM_TRACE_ERR("%s: Nothing pending for promotion!\n",
+ engine->name);
+ return false;
+ }
+
+ if (execlists->pending[execlists_num_ports(execlists)]) {
+ GEM_TRACE_ERR("%s: Excess pending[%d] for promotion!\n",
+ engine->name, execlists_num_ports(execlists));
+ return false;
+ }
+
+ for (port = execlists->pending; (rq = *port); port++) {
+ unsigned long flags;
+ bool ok = true;
+
+ GEM_BUG_ON(!kref_read(&rq->fence.refcount));
+ GEM_BUG_ON(!i915_request_is_active(rq));
+
+ if (ce == rq->context) {
+ GEM_TRACE_ERR("%s: Dup context:%llx in pending[%zd]\n",
+ engine->name,
+ ce->timeline->fence_context,
+ port - execlists->pending);
+ return false;
+ }
+ ce = rq->context;
+
+ if (ccid == ce->lrc.ccid) {
+ GEM_TRACE_ERR("%s: Dup ccid:%x context:%llx in pending[%zd]\n",
+ engine->name,
+ ccid, ce->timeline->fence_context,
+ port - execlists->pending);
+ return false;
+ }
+ ccid = ce->lrc.ccid;
+
+ /*
+ * Sentinels are supposed to be the last request so they flush
+ * the current execution off the HW. Check that they are the only
+ * request in the pending submission.
+ */
+ if (sentinel) {
+ GEM_TRACE_ERR("%s: context:%llx after sentinel in pending[%zd]\n",
+ engine->name,
+ ce->timeline->fence_context,
+ port - execlists->pending);
+ return false;
+ }
+ sentinel = i915_request_has_sentinel(rq);
+
+ /* Hold tightly onto the lock to prevent concurrent retires! */
+ if (!spin_trylock_irqsave(&rq->lock, flags))
+ continue;
+
+ if (i915_request_completed(rq))
+ goto unlock;
+
+ if (i915_active_is_idle(&ce->active) &&
+ !intel_context_is_barrier(ce)) {
+ GEM_TRACE_ERR("%s: Inactive context:%llx in pending[%zd]\n",
+ engine->name,
+ ce->timeline->fence_context,
+ port - execlists->pending);
+ ok = false;
+ goto unlock;
+ }
+
+ if (!i915_vma_is_pinned(ce->state)) {
+ GEM_TRACE_ERR("%s: Unpinned context:%llx in pending[%zd]\n",
+ engine->name,
+ ce->timeline->fence_context,
+ port - execlists->pending);
+ ok = false;
+ goto unlock;
+ }
+
+ if (!i915_vma_is_pinned(ce->ring->vma)) {
+ GEM_TRACE_ERR("%s: Unpinned ring:%llx in pending[%zd]\n",
+ engine->name,
+ ce->timeline->fence_context,
+ port - execlists->pending);
+ ok = false;
+ goto unlock;
+ }
+
+unlock:
+ spin_unlock_irqrestore(&rq->lock, flags);
+ if (!ok)
+ return false;
+ }
+
+ return ce;
+}
+
+static void execlists_submit_ports(struct intel_engine_cs *engine)
+{
+ struct intel_engine_execlists *execlists = &engine->execlists;
+ unsigned int n;
+
+ GEM_BUG_ON(!assert_pending_valid(execlists, "submit"));
+
+ /*
+ * We can skip acquiring intel_runtime_pm_get() here as it was taken
+ * on our behalf by the request (see i915_gem_mark_busy()) and it will
+ * not be relinquished until the device is idle (see
+ * i915_gem_idle_work_handler()). As a precaution, we make sure
+ * that all ELSP are drained i.e. we have processed the CSB,
+ * before allowing ourselves to idle and calling intel_runtime_pm_put().
+ */
+ GEM_BUG_ON(!intel_engine_pm_is_awake(engine));
+
+ /*
+ * ELSQ note: the submit queue is not cleared after being submitted
+ * to the HW so we need to make sure we always clean it up. This is
+ * currently ensured by the fact that we always write the same number
+ * of elsq entries, keep this in mind before changing the loop below.
+ */
+ for (n = execlists_num_ports(execlists); n--; ) {
+ struct i915_request *rq = execlists->pending[n];
+
+ write_desc(execlists,
+ rq ? execlists_update_context(rq) : 0,
+ n);
+ }
+
+ /* we need to manually load the submit queue */
+ if (execlists->ctrl_reg)
+ writel(EL_CTRL_LOAD, execlists->ctrl_reg);
+}
+
+static bool ctx_single_port_submission(const struct intel_context *ce)
+{
+ return (IS_ENABLED(CONFIG_DRM_I915_GVT) &&
+ intel_context_force_single_submission(ce));
+}
+
+static bool can_merge_ctx(const struct intel_context *prev,
+ const struct intel_context *next)
+{
+ if (prev != next)
+ return false;
+
+ if (ctx_single_port_submission(prev))
+ return false;
+
+ return true;
+}
+
+static unsigned long i915_request_flags(const struct i915_request *rq)
+{
+ return READ_ONCE(rq->fence.flags);
+}
+
+static bool can_merge_rq(const struct i915_request *prev,
+ const struct i915_request *next)
+{
+ GEM_BUG_ON(prev == next);
+ GEM_BUG_ON(!assert_priority_queue(prev, next));
+
+ /*
+ * We do not submit known completed requests. Therefore if the next
+ * request is already completed, we can pretend to merge it in
+ * with the previous context (and we will skip updating the ELSP
+ * and tracking). Thus hopefully keeping the ELSP full with active
+ * contexts, despite the best efforts of preempt-to-busy to confuse
+ * us.
+ */
+ if (i915_request_completed(next))
+ return true;
+
+ if (unlikely((i915_request_flags(prev) ^ i915_request_flags(next)) &
+ (BIT(I915_FENCE_FLAG_NOPREEMPT) |
+ BIT(I915_FENCE_FLAG_SENTINEL))))
+ return false;
+
+ if (!can_merge_ctx(prev->context, next->context))
+ return false;
+
+ GEM_BUG_ON(i915_seqno_passed(prev->fence.seqno, next->fence.seqno));
+ return true;
+}
+
+static void virtual_update_register_offsets(u32 *regs,
+ struct intel_engine_cs *engine)
+{
+ set_offsets(regs, reg_offsets(engine), engine, false);
+}
+
+static bool virtual_matches(const struct virtual_engine *ve,
+ const struct i915_request *rq,
+ const struct intel_engine_cs *engine)
+{
+ const struct intel_engine_cs *inflight;
+
+ if (!(rq->execution_mask & engine->mask)) /* We peeked too soon! */
+ return false;
+
+ /*
+ * We track when the HW has completed saving the context image
+ * (i.e. when we have seen the final CS event switching out of
+ * the context) and must not overwrite the context image before
+ * then. This restricts us to only using the active engine
+ * while the previous virtualized request is inflight (so
+ * we reuse the register offsets). This is a very small
+ * hystersis on the greedy seelction algorithm.
+ */
+ inflight = intel_context_inflight(&ve->context);
+ if (inflight && inflight != engine)
+ return false;
+
+ return true;
+}
+
+static void virtual_xfer_context(struct virtual_engine *ve,
+ struct intel_engine_cs *engine)
+{
+ unsigned int n;
+
+ if (likely(engine == ve->siblings[0]))
+ return;
+
+ GEM_BUG_ON(READ_ONCE(ve->context.inflight));
+ if (!intel_engine_has_relative_mmio(engine))
+ virtual_update_register_offsets(ve->context.lrc_reg_state,
+ engine);
+
+ /*
+ * Move the bound engine to the top of the list for
+ * future execution. We then kick this tasklet first
+ * before checking others, so that we preferentially
+ * reuse this set of bound registers.
+ */
+ for (n = 1; n < ve->num_siblings; n++) {
+ if (ve->siblings[n] == engine) {
+ swap(ve->siblings[n], ve->siblings[0]);
+ break;
+ }
+ }
+}
+
+static void defer_request(struct i915_request *rq, struct list_head * const pl)
+{
+ LIST_HEAD(list);
+
+ /*
+ * We want to move the interrupted request to the back of
+ * the round-robin list (i.e. its priority level), but
+ * in doing so, we must then move all requests that were in
+ * flight and were waiting for the interrupted request to
+ * be run after it again.
+ */
+ do {
+ struct i915_dependency *p;
+
+ GEM_BUG_ON(i915_request_is_active(rq));
+ list_move_tail(&rq->sched.link, pl);
+
+ for_each_waiter(p, rq) {
+ struct i915_request *w =
+ container_of(p->waiter, typeof(*w), sched);
+
+ if (p->flags & I915_DEPENDENCY_WEAK)
+ continue;
+
+ /* Leave semaphores spinning on the other engines */
+ if (w->engine != rq->engine)
+ continue;
+
+ /* No waiter should start before its signaler */
+ GEM_BUG_ON(i915_request_has_initial_breadcrumb(w) &&
+ i915_request_started(w) &&
+ !i915_request_completed(rq));
+
+ GEM_BUG_ON(i915_request_is_active(w));
+ if (!i915_request_is_ready(w))
+ continue;
+
+ if (rq_prio(w) < rq_prio(rq))
+ continue;
+
+ GEM_BUG_ON(rq_prio(w) > rq_prio(rq));
+ list_move_tail(&w->sched.link, &list);
+ }
+
+ rq = list_first_entry_or_null(&list, typeof(*rq), sched.link);
+ } while (rq);
+}
+
+static void defer_active(struct intel_engine_cs *engine)
+{
+ struct i915_request *rq;
+
+ rq = __unwind_incomplete_requests(engine);
+ if (!rq)
+ return;
+
+ defer_request(rq, i915_sched_lookup_priolist(engine, rq_prio(rq)));
+}
+
+static bool
+need_timeslice(const struct intel_engine_cs *engine,
+ const struct i915_request *rq,
+ const struct rb_node *rb)
+{
+ int hint;
+
+ if (!intel_engine_has_timeslices(engine))
+ return false;
+
+ hint = engine->execlists.queue_priority_hint;
+
+ if (rb) {
+ const struct virtual_engine *ve =
+ rb_entry(rb, typeof(*ve), nodes[engine->id].rb);
+ const struct intel_engine_cs *inflight =
+ intel_context_inflight(&ve->context);
+
+ if (!inflight || inflight == engine) {
+ struct i915_request *next;
+
+ rcu_read_lock();
+ next = READ_ONCE(ve->request);
+ if (next)
+ hint = max(hint, rq_prio(next));
+ rcu_read_unlock();
+ }
+ }
+
+ if (!list_is_last(&rq->sched.link, &engine->active.requests))
+ hint = max(hint, rq_prio(list_next_entry(rq, sched.link)));
+
+ GEM_BUG_ON(hint >= I915_PRIORITY_UNPREEMPTABLE);
+ return hint >= effective_prio(rq);
+}
+
+static bool
+timeslice_yield(const struct intel_engine_execlists *el,
+ const struct i915_request *rq)
+{
+ /*
+ * Once bitten, forever smitten!
+ *
+ * If the active context ever busy-waited on a semaphore,
+ * it will be treated as a hog until the end of its timeslice (i.e.
+ * until it is scheduled out and replaced by a new submission,
+ * possibly even its own lite-restore). The HW only sends an interrupt
+ * on the first miss, and we do know if that semaphore has been
+ * signaled, or even if it is now stuck on another semaphore. Play
+ * safe, yield if it might be stuck -- it will be given a fresh
+ * timeslice in the near future.
+ */
+ return rq->context->lrc.ccid == READ_ONCE(el->yield);
+}
+
+static bool
+timeslice_expired(const struct intel_engine_execlists *el,
+ const struct i915_request *rq)
+{
+ return timer_expired(&el->timer) || timeslice_yield(el, rq);
+}
+
+static int
+switch_prio(struct intel_engine_cs *engine, const struct i915_request *rq)
+{
+ if (list_is_last(&rq->sched.link, &engine->active.requests))
+ return engine->execlists.queue_priority_hint;
+
+ return rq_prio(list_next_entry(rq, sched.link));
+}
+
+static inline unsigned long
+timeslice(const struct intel_engine_cs *engine)
+{
+ return READ_ONCE(engine->props.timeslice_duration_ms);
+}
+
+static unsigned long active_timeslice(const struct intel_engine_cs *engine)
+{
+ const struct intel_engine_execlists *execlists = &engine->execlists;
+ const struct i915_request *rq = *execlists->active;
+
+ if (!rq || i915_request_completed(rq))
+ return 0;
+
+ if (READ_ONCE(execlists->switch_priority_hint) < effective_prio(rq))
+ return 0;
+
+ return timeslice(engine);
+}
+
+static void set_timeslice(struct intel_engine_cs *engine)
+{
+ unsigned long duration;
+
+ if (!intel_engine_has_timeslices(engine))
+ return;
+
+ duration = active_timeslice(engine);
+ ENGINE_TRACE(engine, "bump timeslicing, interval:%lu", duration);
+
+ set_timer_ms(&engine->execlists.timer, duration);
+}
+
+static void start_timeslice(struct intel_engine_cs *engine, int prio)
+{
+ struct intel_engine_execlists *execlists = &engine->execlists;
+ unsigned long duration;
+
+ if (!intel_engine_has_timeslices(engine))
+ return;
+
+ WRITE_ONCE(execlists->switch_priority_hint, prio);
+ if (prio == INT_MIN)
+ return;
+
+ if (timer_pending(&execlists->timer))
+ return;
+
+ duration = timeslice(engine);
+ ENGINE_TRACE(engine,
+ "start timeslicing, prio:%d, interval:%lu",
+ prio, duration);
+
+ set_timer_ms(&execlists->timer, duration);
+}
+
+static void record_preemption(struct intel_engine_execlists *execlists)
+{
+ (void)I915_SELFTEST_ONLY(execlists->preempt_hang.count++);
+}
+
+static unsigned long active_preempt_timeout(struct intel_engine_cs *engine,
+ const struct i915_request *rq)
+{
+ if (!rq)
+ return 0;
+
+ /* Force a fast reset for terminated contexts (ignoring sysfs!) */
+ if (unlikely(intel_context_is_banned(rq->context)))
+ return 1;
+
+ return READ_ONCE(engine->props.preempt_timeout_ms);
+}
+
+static void set_preempt_timeout(struct intel_engine_cs *engine,
+ const struct i915_request *rq)
+{
+ if (!intel_engine_has_preempt_reset(engine))
+ return;
+
+ set_timer_ms(&engine->execlists.preempt,
+ active_preempt_timeout(engine, rq));
+}
+
+static inline void clear_ports(struct i915_request **ports, int count)
+{
+ memset_p((void **)ports, NULL, count);
+}
+
+static inline void
+copy_ports(struct i915_request **dst, struct i915_request **src, int count)
+{
+ /* A memcpy_p() would be very useful here! */
+ while (count--)
+ WRITE_ONCE(*dst++, *src++); /* avoid write tearing */
+}
+
+static void execlists_dequeue(struct intel_engine_cs *engine)
+{
+ struct intel_engine_execlists * const execlists = &engine->execlists;
+ struct i915_request **port = execlists->pending;
+ struct i915_request ** const last_port = port + execlists->port_mask;
+ struct i915_request * const *active;
+ struct i915_request *last;
+ struct rb_node *rb;
+ bool submit = false;
+
+ /*
+ * Hardware submission is through 2 ports. Conceptually each port
+ * has a (RING_START, RING_HEAD, RING_TAIL) tuple. RING_START is
+ * static for a context, and unique to each, so we only execute
+ * requests belonging to a single context from each ring. RING_HEAD
+ * is maintained by the CS in the context image, it marks the place
+ * where it got up to last time, and through RING_TAIL we tell the CS
+ * where we want to execute up to this time.
+ *
+ * In this list the requests are in order of execution. Consecutive
+ * requests from the same context are adjacent in the ringbuffer. We
+ * can combine these requests into a single RING_TAIL update:
+ *
+ * RING_HEAD...req1...req2
+ * ^- RING_TAIL
+ * since to execute req2 the CS must first execute req1.
+ *
+ * Our goal then is to point each port to the end of a consecutive
+ * sequence of requests as being the most optimal (fewest wake ups
+ * and context switches) submission.
+ */
+
+ for (rb = rb_first_cached(&execlists->virtual); rb; ) {
+ struct virtual_engine *ve =
+ rb_entry(rb, typeof(*ve), nodes[engine->id].rb);
+ struct i915_request *rq = READ_ONCE(ve->request);
+
+ if (!rq) { /* lazily cleanup after another engine handled rq */
+ rb_erase_cached(rb, &execlists->virtual);
+ RB_CLEAR_NODE(rb);
+ rb = rb_first_cached(&execlists->virtual);
+ continue;
+ }
+
+ if (!virtual_matches(ve, rq, engine)) {
+ rb = rb_next(rb);
+ continue;
+ }
+
+ break;
+ }
+
+ /*
+ * If the queue is higher priority than the last
+ * request in the currently active context, submit afresh.
+ * We will resubmit again afterwards in case we need to split
+ * the active context to interject the preemption request,
+ * i.e. we will retrigger preemption following the ack in case
+ * of trouble.
+ */
+ active = READ_ONCE(execlists->active);
+
+ /*
+ * In theory we can skip over completed contexts that have not
+ * yet been processed by events (as those events are in flight):
+ *
+ * while ((last = *active) && i915_request_completed(last))
+ * active++;
+ *
+ * However, the GPU cannot handle this as it will ultimately
+ * find itself trying to jump back into a context it has just
+ * completed and barf.
+ */
+
+ if ((last = *active)) {
+ if (i915_request_completed(last)) {
+ goto check_secondary;
+ } else if (need_preempt(engine, last, rb)) {
+ ENGINE_TRACE(engine,
+ "preempting last=%llx:%lld, prio=%d, hint=%d\n",
+ last->fence.context,
+ last->fence.seqno,
+ last->sched.attr.priority,
+ execlists->queue_priority_hint);
+ record_preemption(execlists);
+
+ /*
+ * Don't let the RING_HEAD advance past the breadcrumb
+ * as we unwind (and until we resubmit) so that we do
+ * not accidentally tell it to go backwards.
+ */
+ ring_set_paused(engine, 1);
+
+ /*
+ * Note that we have not stopped the GPU at this point,
+ * so we are unwinding the incomplete requests as they
+ * remain inflight and so by the time we do complete
+ * the preemption, some of the unwound requests may
+ * complete!
+ */
+ __unwind_incomplete_requests(engine);
+
+ last = NULL;
+ } else if (need_timeslice(engine, last, rb) &&
+ timeslice_expired(execlists, last)) {
+ ENGINE_TRACE(engine,
+ "expired last=%llx:%lld, prio=%d, hint=%d, yield?=%s\n",
+ last->fence.context,
+ last->fence.seqno,
+ last->sched.attr.priority,
+ execlists->queue_priority_hint,
+ yesno(timeslice_yield(execlists, last)));
+
+ ring_set_paused(engine, 1);
+ defer_active(engine);
+
+ /*
+ * Unlike for preemption, if we rewind and continue
+ * executing the same context as previously active,
+ * the order of execution will remain the same and
+ * the tail will only advance. We do not need to
+ * force a full context restore, as a lite-restore
+ * is sufficient to resample the monotonic TAIL.
+ *
+ * If we switch to any other context, similarly we
+ * will not rewind TAIL of current context, and
+ * normal save/restore will preserve state and allow
+ * us to later continue executing the same request.
+ */
+ last = NULL;
+ } else {
+ /*
+ * Otherwise if we already have a request pending
+ * for execution after the current one, we can
+ * just wait until the next CS event before
+ * queuing more. In either case we will force a
+ * lite-restore preemption event, but if we wait
+ * we hopefully coalesce several updates into a single
+ * submission.
+ */
+check_secondary:
+ if (!list_is_last(&last->sched.link,
+ &engine->active.requests)) {
+ /*
+ * Even if ELSP[1] is occupied and not worthy
+ * of timeslices, our queue might be.
+ */
+ start_timeslice(engine, queue_prio(execlists));
+ return;
+ }
+ }
+ }
+
+ while (rb) { /* XXX virtual is always taking precedence */
+ struct virtual_engine *ve =
+ rb_entry(rb, typeof(*ve), nodes[engine->id].rb);
+ struct i915_request *rq;
+
+ spin_lock(&ve->base.active.lock);
+
+ rq = ve->request;
+ if (unlikely(!rq)) { /* lost the race to a sibling */
+ spin_unlock(&ve->base.active.lock);
+ rb_erase_cached(rb, &execlists->virtual);
+ RB_CLEAR_NODE(rb);
+ rb = rb_first_cached(&execlists->virtual);
+ continue;
+ }
+
+ GEM_BUG_ON(rq != ve->request);
+ GEM_BUG_ON(rq->engine != &ve->base);
+ GEM_BUG_ON(rq->context != &ve->context);
+
+ if (rq_prio(rq) >= queue_prio(execlists)) {
+ if (!virtual_matches(ve, rq, engine)) {
+ spin_unlock(&ve->base.active.lock);
+ rb = rb_next(rb);
+ continue;
+ }
+
+ if (last && !can_merge_rq(last, rq)) {
+ spin_unlock(&ve->base.active.lock);
+ start_timeslice(engine, rq_prio(rq));
+ return; /* leave this for another sibling */
+ }
+
+ ENGINE_TRACE(engine,
+ "virtual rq=%llx:%lld%s, new engine? %s\n",
+ rq->fence.context,
+ rq->fence.seqno,
+ i915_request_completed(rq) ? "!" :
+ i915_request_started(rq) ? "*" :
+ "",
+ yesno(engine != ve->siblings[0]));
+
+ WRITE_ONCE(ve->request, NULL);
+ WRITE_ONCE(ve->base.execlists.queue_priority_hint,
+ INT_MIN);
+ rb_erase_cached(rb, &execlists->virtual);
+ RB_CLEAR_NODE(rb);
+
+ GEM_BUG_ON(!(rq->execution_mask & engine->mask));
+ WRITE_ONCE(rq->engine, engine);
+
+ if (__i915_request_submit(rq)) {
+ /*
+ * Only after we confirm that we will submit
+ * this request (i.e. it has not already
+ * completed), do we want to update the context.
+ *
+ * This serves two purposes. It avoids
+ * unnecessary work if we are resubmitting an
+ * already completed request after timeslicing.
+ * But more importantly, it prevents us altering
+ * ve->siblings[] on an idle context, where
+ * we may be using ve->siblings[] in
+ * virtual_context_enter / virtual_context_exit.
+ */
+ virtual_xfer_context(ve, engine);
+ GEM_BUG_ON(ve->siblings[0] != engine);
+
+ submit = true;
+ last = rq;
+ }
+ i915_request_put(rq);
+
+ /*
+ * Hmm, we have a bunch of virtual engine requests,
+ * but the first one was already completed (thanks
+ * preempt-to-busy!). Keep looking at the veng queue
+ * until we have no more relevant requests (i.e.
+ * the normal submit queue has higher priority).
+ */
+ if (!submit) {
+ spin_unlock(&ve->base.active.lock);
+ rb = rb_first_cached(&execlists->virtual);
+ continue;
+ }
+ }
+
+ spin_unlock(&ve->base.active.lock);
+ break;
+ }
+
+ while ((rb = rb_first_cached(&execlists->queue))) {
+ struct i915_priolist *p = to_priolist(rb);
+ struct i915_request *rq, *rn;
+ int i;
+
+ priolist_for_each_request_consume(rq, rn, p, i) {
+ bool merge = true;
+
+ /*
+ * Can we combine this request with the current port?
+ * It has to be the same context/ringbuffer and not
+ * have any exceptions (e.g. GVT saying never to
+ * combine contexts).
+ *
+ * If we can combine the requests, we can execute both
+ * by updating the RING_TAIL to point to the end of the
+ * second request, and so we never need to tell the
+ * hardware about the first.
+ */
+ if (last && !can_merge_rq(last, rq)) {
+ /*
+ * If we are on the second port and cannot
+ * combine this request with the last, then we
+ * are done.
+ */
+ if (port == last_port)
+ goto done;
+
+ /*
+ * We must not populate both ELSP[] with the
+ * same LRCA, i.e. we must submit 2 different
+ * contexts if we submit 2 ELSP.
+ */
+ if (last->context == rq->context)
+ goto done;
+
+ if (i915_request_has_sentinel(last))
+ goto done;
+
+ /*
+ * If GVT overrides us we only ever submit
+ * port[0], leaving port[1] empty. Note that we
+ * also have to be careful that we don't queue
+ * the same context (even though a different
+ * request) to the second port.
+ */
+ if (ctx_single_port_submission(last->context) ||
+ ctx_single_port_submission(rq->context))
+ goto done;
+
+ merge = false;
+ }
+
+ if (__i915_request_submit(rq)) {
+ if (!merge) {
+ *port = execlists_schedule_in(last, port - execlists->pending);
+ port++;
+ last = NULL;
+ }
+
+ GEM_BUG_ON(last &&
+ !can_merge_ctx(last->context,
+ rq->context));
+ GEM_BUG_ON(last &&
+ i915_seqno_passed(last->fence.seqno,
+ rq->fence.seqno));
+
+ submit = true;
+ last = rq;
+ }
+ }
+
+ rb_erase_cached(&p->node, &execlists->queue);
+ i915_priolist_free(p);
+ }
+
+done:
+ /*
+ * Here be a bit of magic! Or sleight-of-hand, whichever you prefer.
+ *
+ * We choose the priority hint such that if we add a request of greater
+ * priority than this, we kick the submission tasklet to decide on
+ * the right order of submitting the requests to hardware. We must
+ * also be prepared to reorder requests as they are in-flight on the
+ * HW. We derive the priority hint then as the first "hole" in
+ * the HW submission ports and if there are no available slots,
+ * the priority of the lowest executing request, i.e. last.
+ *
+ * When we do receive a higher priority request ready to run from the
+ * user, see queue_request(), the priority hint is bumped to that
+ * request triggering preemption on the next dequeue (or subsequent
+ * interrupt for secondary ports).
+ */
+ execlists->queue_priority_hint = queue_prio(execlists);
+
+ if (submit) {
+ *port = execlists_schedule_in(last, port - execlists->pending);
+ execlists->switch_priority_hint =
+ switch_prio(engine, *execlists->pending);
+
+ /*
+ * Skip if we ended up with exactly the same set of requests,
+ * e.g. trying to timeslice a pair of ordered contexts
+ */
+ if (!memcmp(active, execlists->pending,
+ (port - execlists->pending + 1) * sizeof(*port))) {
+ do
+ execlists_schedule_out(fetch_and_zero(port));
+ while (port-- != execlists->pending);
+
+ goto skip_submit;
+ }
+ clear_ports(port + 1, last_port - port);
+
+ WRITE_ONCE(execlists->yield, -1);
+ set_preempt_timeout(engine, *active);
+ execlists_submit_ports(engine);
+ } else {
+ start_timeslice(engine, execlists->queue_priority_hint);
+skip_submit:
+ ring_set_paused(engine, 0);
+ }
+}
+
+static void
+cancel_port_requests(struct intel_engine_execlists * const execlists)
+{
+ struct i915_request * const *port;
+
+ for (port = execlists->pending; *port; port++)
+ execlists_schedule_out(*port);
+ clear_ports(execlists->pending, ARRAY_SIZE(execlists->pending));
+
+ /* Mark the end of active before we overwrite *active */
+ for (port = xchg(&execlists->active, execlists->pending); *port; port++)
+ execlists_schedule_out(*port);
+ clear_ports(execlists->inflight, ARRAY_SIZE(execlists->inflight));
+
+ smp_wmb(); /* complete the seqlock for execlists_active() */
+ WRITE_ONCE(execlists->active, execlists->inflight);
+
+ /* Having cancelled all outstanding process_csb(), stop their timers */
+ GEM_BUG_ON(execlists->pending[0]);
+ cancel_timer(&execlists->timer);
+ cancel_timer(&execlists->preempt);
+}
+
+static inline void
+invalidate_csb_entries(const u64 *first, const u64 *last)
+{
+ clflush((void *)first);
+ clflush((void *)last);
+}
+
+/*
+ * Starting with Gen12, the status has a new format:
+ *
+ * bit 0: switched to new queue
+ * bit 1: reserved
+ * bit 2: semaphore wait mode (poll or signal), only valid when
+ * switch detail is set to "wait on semaphore"
+ * bits 3-5: engine class
+ * bits 6-11: engine instance
+ * bits 12-14: reserved
+ * bits 15-25: sw context id of the lrc the GT switched to
+ * bits 26-31: sw counter of the lrc the GT switched to
+ * bits 32-35: context switch detail
+ * - 0: ctx complete
+ * - 1: wait on sync flip
+ * - 2: wait on vblank
+ * - 3: wait on scanline
+ * - 4: wait on semaphore
+ * - 5: context preempted (not on SEMAPHORE_WAIT or
+ * WAIT_FOR_EVENT)
+ * bit 36: reserved
+ * bits 37-43: wait detail (for switch detail 1 to 4)
+ * bits 44-46: reserved
+ * bits 47-57: sw context id of the lrc the GT switched away from
+ * bits 58-63: sw counter of the lrc the GT switched away from
+ */
+static inline bool gen12_csb_parse(const u64 csb)
+{
+ bool ctx_away_valid = GEN12_CSB_CTX_VALID(upper_32_bits(csb));
+ bool new_queue =
+ lower_32_bits(csb) & GEN12_CTX_STATUS_SWITCHED_TO_NEW_QUEUE;
+
+ /*
+ * The context switch detail is not guaranteed to be 5 when a preemption
+ * occurs, so we can't just check for that. The check below works for
+ * all the cases we care about, including preemptions of WAIT
+ * instructions and lite-restore. Preempt-to-idle via the CTRL register
+ * would require some extra handling, but we don't support that.
+ */
+ if (!ctx_away_valid || new_queue) {
+ GEM_BUG_ON(!GEN12_CSB_CTX_VALID(lower_32_bits(csb)));
+ return true;
+ }
+
+ /*
+ * switch detail = 5 is covered by the case above and we do not expect a
+ * context switch on an unsuccessful wait instruction since we always
+ * use polling mode.
+ */
+ GEM_BUG_ON(GEN12_CTX_SWITCH_DETAIL(upper_32_bits(csb)));
+ return false;
+}
+
+static inline bool gen8_csb_parse(const u64 csb)
+{
+ return csb & (GEN8_CTX_STATUS_IDLE_ACTIVE | GEN8_CTX_STATUS_PREEMPTED);
+}
+
+static noinline u64
+wa_csb_read(const struct intel_engine_cs *engine, u64 * const csb)
+{
+ u64 entry;
+
+ /*
+ * Reading from the HWSP has one particular advantage: we can detect
+ * a stale entry. Since the write into HWSP is broken, we have no reason
+ * to trust the HW at all, the mmio entry may equally be unordered, so
+ * we prefer the path that is self-checking and as a last resort,
+ * return the mmio value.
+ *
+ * tgl,dg1:HSDES#22011327657
+ */
+ preempt_disable();
+ if (wait_for_atomic_us((entry = READ_ONCE(*csb)) != -1, 10)) {
+ int idx = csb - engine->execlists.csb_status;
+ int status;
+
+ status = GEN8_EXECLISTS_STATUS_BUF;
+ if (idx >= 6) {
+ status = GEN11_EXECLISTS_STATUS_BUF2;
+ idx -= 6;
+ }
+ status += sizeof(u64) * idx;
+
+ entry = intel_uncore_read64(engine->uncore,
+ _MMIO(engine->mmio_base + status));
+ }
+ preempt_enable();
+
+ return entry;
+}
+
+static inline u64
+csb_read(const struct intel_engine_cs *engine, u64 * const csb)
+{
+ u64 entry = READ_ONCE(*csb);
+
+ /*
+ * Unfortunately, the GPU does not always serialise its write
+ * of the CSB entries before its write of the CSB pointer, at least
+ * from the perspective of the CPU, using what is known as a Global
+ * Observation Point. We may read a new CSB tail pointer, but then
+ * read the stale CSB entries, causing us to misinterpret the
+ * context-switch events, and eventually declare the GPU hung.
+ *
+ * icl:HSDES#1806554093
+ * tgl:HSDES#22011248461
+ */
+ if (unlikely(entry == -1))
+ entry = wa_csb_read(engine, csb);
+
+ /* Consume this entry so that we can spot its future reuse. */
+ WRITE_ONCE(*csb, -1);
+
+ /* ELSP is an implicit wmb() before the GPU wraps and overwrites csb */
+ return entry;
+}
+
+static void process_csb(struct intel_engine_cs *engine)
+{
+ struct intel_engine_execlists * const execlists = &engine->execlists;
+ u64 * const buf = execlists->csb_status;
+ const u8 num_entries = execlists->csb_size;
+ u8 head, tail;
+
+ /*
+ * As we modify our execlists state tracking we require exclusive
+ * access. Either we are inside the tasklet, or the tasklet is disabled
+ * and we assume that is only inside the reset paths and so serialised.
+ */
+ GEM_BUG_ON(!tasklet_is_locked(&execlists->tasklet) &&
+ !reset_in_progress(execlists));
+ GEM_BUG_ON(!intel_engine_in_execlists_submission_mode(engine));
+
+ /*
+ * Note that csb_write, csb_status may be either in HWSP or mmio.
+ * When reading from the csb_write mmio register, we have to be
+ * careful to only use the GEN8_CSB_WRITE_PTR portion, which is
+ * the low 4bits. As it happens we know the next 4bits are always
+ * zero and so we can simply masked off the low u8 of the register
+ * and treat it identically to reading from the HWSP (without having
+ * to use explicit shifting and masking, and probably bifurcating
+ * the code to handle the legacy mmio read).
+ */
+ head = execlists->csb_head;
+ tail = READ_ONCE(*execlists->csb_write);
+ if (unlikely(head == tail))
+ return;
+
+ /*
+ * We will consume all events from HW, or at least pretend to.
+ *
+ * The sequence of events from the HW is deterministic, and derived
+ * from our writes to the ELSP, with a smidgen of variability for
+ * the arrival of the asynchronous requests wrt to the inflight
+ * execution. If the HW sends an event that does not correspond with
+ * the one we are expecting, we have to abandon all hope as we lose
+ * all tracking of what the engine is actually executing. We will
+ * only detect we are out of sequence with the HW when we get an
+ * 'impossible' event because we have already drained our own
+ * preemption/promotion queue. If this occurs, we know that we likely
+ * lost track of execution earlier and must unwind and restart, the
+ * simplest way is by stop processing the event queue and force the
+ * engine to reset.
+ */
+ execlists->csb_head = tail;
+ ENGINE_TRACE(engine, "cs-irq head=%d, tail=%d\n", head, tail);
+
+ /*
+ * Hopefully paired with a wmb() in HW!
+ *
+ * We must complete the read of the write pointer before any reads
+ * from the CSB, so that we do not see stale values. Without an rmb
+ * (lfence) the HW may speculatively perform the CSB[] reads *before*
+ * we perform the READ_ONCE(*csb_write).
+ */
+ rmb();
+ do {
+ bool promote;
+ u64 csb;
+
+ if (++head == num_entries)
+ head = 0;
+
+ /*
+ * We are flying near dragons again.
+ *
+ * We hold a reference to the request in execlist_port[]
+ * but no more than that. We are operating in softirq
+ * context and so cannot hold any mutex or sleep. That
+ * prevents us stopping the requests we are processing
+ * in port[] from being retired simultaneously (the
+ * breadcrumb will be complete before we see the
+ * context-switch). As we only hold the reference to the
+ * request, any pointer chasing underneath the request
+ * is subject to a potential use-after-free. Thus we
+ * store all of the bookkeeping within port[] as
+ * required, and avoid using unguarded pointers beneath
+ * request itself. The same applies to the atomic
+ * status notifier.
+ */
+
+ csb = csb_read(engine, buf + head);
+ ENGINE_TRACE(engine, "csb[%d]: status=0x%08x:0x%08x\n",
+ head, upper_32_bits(csb), lower_32_bits(csb));
+
+ if (INTEL_GEN(engine->i915) >= 12)
+ promote = gen12_csb_parse(csb);
+ else
+ promote = gen8_csb_parse(csb);
+ if (promote) {
+ struct i915_request * const *old = execlists->active;
+
+ if (GEM_WARN_ON(!*execlists->pending)) {
+ execlists->error_interrupt |= ERROR_CSB;
+ break;
+ }
+
+ ring_set_paused(engine, 0);
+
+ /* Point active to the new ELSP; prevent overwriting */
+ WRITE_ONCE(execlists->active, execlists->pending);
+ smp_wmb(); /* notify execlists_active() */
+
+ /* cancel old inflight, prepare for switch */
+ trace_ports(execlists, "preempted", old);
+ while (*old)
+ execlists_schedule_out(*old++);
+
+ /* switch pending to inflight */
+ GEM_BUG_ON(!assert_pending_valid(execlists, "promote"));
+ copy_ports(execlists->inflight,
+ execlists->pending,
+ execlists_num_ports(execlists));
+ smp_wmb(); /* complete the seqlock */
+ WRITE_ONCE(execlists->active, execlists->inflight);
+
+ /* XXX Magic delay for tgl */
+ ENGINE_POSTING_READ(engine, RING_CONTEXT_STATUS_PTR);
+
+ WRITE_ONCE(execlists->pending[0], NULL);
+ } else {
+ if (GEM_WARN_ON(!*execlists->active)) {
+ execlists->error_interrupt |= ERROR_CSB;
+ break;
+ }
+
+ /* port0 completed, advanced to port1 */
+ trace_ports(execlists, "completed", execlists->active);
+
+ /*
+ * We rely on the hardware being strongly
+ * ordered, that the breadcrumb write is
+ * coherent (visible from the CPU) before the
+ * user interrupt is processed. One might assume
+ * that the breadcrumb write being before the
+ * user interrupt and the CS event for the context
+ * switch would therefore be before the CS event
+ * itself...
+ */
+ if (GEM_SHOW_DEBUG() &&
+ !i915_request_completed(*execlists->active)) {
+ struct i915_request *rq = *execlists->active;
+ const u32 *regs __maybe_unused =
+ rq->context->lrc_reg_state;
+
+ ENGINE_TRACE(engine,
+ "context completed before request!\n");
+ ENGINE_TRACE(engine,
+ "ring:{start:0x%08x, head:%04x, tail:%04x, ctl:%08x, mode:%08x}\n",
+ ENGINE_READ(engine, RING_START),
+ ENGINE_READ(engine, RING_HEAD) & HEAD_ADDR,
+ ENGINE_READ(engine, RING_TAIL) & TAIL_ADDR,
+ ENGINE_READ(engine, RING_CTL),
+ ENGINE_READ(engine, RING_MI_MODE));
+ ENGINE_TRACE(engine,
+ "rq:{start:%08x, head:%04x, tail:%04x, seqno:%llx:%d, hwsp:%d}, ",
+ i915_ggtt_offset(rq->ring->vma),
+ rq->head, rq->tail,
+ rq->fence.context,
+ lower_32_bits(rq->fence.seqno),
+ hwsp_seqno(rq));
+ ENGINE_TRACE(engine,
+ "ctx:{start:%08x, head:%04x, tail:%04x}, ",
+ regs[CTX_RING_START],
+ regs[CTX_RING_HEAD],
+ regs[CTX_RING_TAIL]);
+ }
+
+ execlists_schedule_out(*execlists->active++);
+
+ GEM_BUG_ON(execlists->active - execlists->inflight >
+ execlists_num_ports(execlists));
+ }
+ } while (head != tail);
+
+ set_timeslice(engine);
+
+ /*
+ * Gen11 has proven to fail wrt global observation point between
+ * entry and tail update, failing on the ordering and thus
+ * we see an old entry in the context status buffer.
+ *
+ * Forcibly evict out entries for the next gpu csb update,
+ * to increase the odds that we get a fresh entries with non
+ * working hardware. The cost for doing so comes out mostly with
+ * the wash as hardware, working or not, will need to do the
+ * invalidation before.
+ */
+ invalidate_csb_entries(&buf[0], &buf[num_entries - 1]);
+}
+
+static void __execlists_submission_tasklet(struct intel_engine_cs *const engine)
+{
+ lockdep_assert_held(&engine->active.lock);
+ if (!READ_ONCE(engine->execlists.pending[0])) {
+ rcu_read_lock(); /* protect peeking at execlists->active */
+ execlists_dequeue(engine);
+ rcu_read_unlock();
+ }
+}
+
+static void __execlists_hold(struct i915_request *rq)
+{
+ LIST_HEAD(list);
+
+ do {
+ struct i915_dependency *p;
+
+ if (i915_request_is_active(rq))
+ __i915_request_unsubmit(rq);
+
+ clear_bit(I915_FENCE_FLAG_PQUEUE, &rq->fence.flags);
+ list_move_tail(&rq->sched.link, &rq->engine->active.hold);
+ i915_request_set_hold(rq);
+ RQ_TRACE(rq, "on hold\n");
+
+ for_each_waiter(p, rq) {
+ struct i915_request *w =
+ container_of(p->waiter, typeof(*w), sched);
+
+ /* Leave semaphores spinning on the other engines */
+ if (w->engine != rq->engine)
+ continue;
+
+ if (!i915_request_is_ready(w))
+ continue;
+
+ if (i915_request_completed(w))
+ continue;
+
+ if (i915_request_on_hold(w))
+ continue;
+
+ list_move_tail(&w->sched.link, &list);
+ }
+
+ rq = list_first_entry_or_null(&list, typeof(*rq), sched.link);
+ } while (rq);
+}
+
+static bool execlists_hold(struct intel_engine_cs *engine,
+ struct i915_request *rq)
+{
+ if (i915_request_on_hold(rq))
+ return false;
+
+ spin_lock_irq(&engine->active.lock);
+
+ if (i915_request_completed(rq)) { /* too late! */
+ rq = NULL;
+ goto unlock;
+ }
+
+ if (rq->engine != engine) { /* preempted virtual engine */
+ struct virtual_engine *ve = to_virtual_engine(rq->engine);
+
+ /*
+ * intel_context_inflight() is only protected by virtue
+ * of process_csb() being called only by the tasklet (or
+ * directly from inside reset while the tasklet is suspended).
+ * Assert that neither of those are allowed to run while we
+ * poke at the request queues.
+ */
+ GEM_BUG_ON(!reset_in_progress(&engine->execlists));
+
+ /*
+ * An unsubmitted request along a virtual engine will
+ * remain on the active (this) engine until we are able
+ * to process the context switch away (and so mark the
+ * context as no longer in flight). That cannot have happened
+ * yet, otherwise we would not be hanging!
+ */
+ spin_lock(&ve->base.active.lock);
+ GEM_BUG_ON(intel_context_inflight(rq->context) != engine);
+ GEM_BUG_ON(ve->request != rq);
+ ve->request = NULL;
+ spin_unlock(&ve->base.active.lock);
+ i915_request_put(rq);
+
+ rq->engine = engine;
+ }
+
+ /*
+ * Transfer this request onto the hold queue to prevent it
+ * being resumbitted to HW (and potentially completed) before we have
+ * released it. Since we may have already submitted following
+ * requests, we need to remove those as well.
+ */
+ GEM_BUG_ON(i915_request_on_hold(rq));
+ GEM_BUG_ON(rq->engine != engine);
+ __execlists_hold(rq);
+ GEM_BUG_ON(list_empty(&engine->active.hold));
+
+unlock:
+ spin_unlock_irq(&engine->active.lock);
+ return rq;
+}
+
+static bool hold_request(const struct i915_request *rq)
+{
+ struct i915_dependency *p;
+ bool result = false;
+
+ /*
+ * If one of our ancestors is on hold, we must also be on hold,
+ * otherwise we will bypass it and execute before it.
+ */
+ rcu_read_lock();
+ for_each_signaler(p, rq) {
+ const struct i915_request *s =
+ container_of(p->signaler, typeof(*s), sched);
+
+ if (s->engine != rq->engine)
+ continue;
+
+ result = i915_request_on_hold(s);
+ if (result)
+ break;
+ }
+ rcu_read_unlock();
+
+ return result;
+}
+
+static void __execlists_unhold(struct i915_request *rq)
+{
+ LIST_HEAD(list);
+
+ do {
+ struct i915_dependency *p;
+
+ RQ_TRACE(rq, "hold release\n");
+
+ GEM_BUG_ON(!i915_request_on_hold(rq));
+ GEM_BUG_ON(!i915_sw_fence_signaled(&rq->submit));
+
+ i915_request_clear_hold(rq);
+ list_move_tail(&rq->sched.link,
+ i915_sched_lookup_priolist(rq->engine,
+ rq_prio(rq)));
+ set_bit(I915_FENCE_FLAG_PQUEUE, &rq->fence.flags);
+
+ /* Also release any children on this engine that are ready */
+ for_each_waiter(p, rq) {
+ struct i915_request *w =
+ container_of(p->waiter, typeof(*w), sched);
+
+ /* Propagate any change in error status */
+ if (rq->fence.error)
+ i915_request_set_error_once(w, rq->fence.error);
+
+ if (w->engine != rq->engine)
+ continue;
+
+ if (!i915_request_on_hold(w))
+ continue;
+
+ /* Check that no other parents are also on hold */
+ if (hold_request(w))
+ continue;
+
+ list_move_tail(&w->sched.link, &list);
+ }
+
+ rq = list_first_entry_or_null(&list, typeof(*rq), sched.link);
+ } while (rq);
+}
+
+static void execlists_unhold(struct intel_engine_cs *engine,
+ struct i915_request *rq)
+{
+ spin_lock_irq(&engine->active.lock);
+
+ /*
+ * Move this request back to the priority queue, and all of its
+ * children and grandchildren that were suspended along with it.
+ */
+ __execlists_unhold(rq);
+
+ if (rq_prio(rq) > engine->execlists.queue_priority_hint) {
+ engine->execlists.queue_priority_hint = rq_prio(rq);
+ tasklet_hi_schedule(&engine->execlists.tasklet);
+ }
+
+ spin_unlock_irq(&engine->active.lock);
+}
+
+struct execlists_capture {
+ struct work_struct work;
+ struct i915_request *rq;
+ struct i915_gpu_coredump *error;
+};
+
+static void execlists_capture_work(struct work_struct *work)
+{
+ struct execlists_capture *cap = container_of(work, typeof(*cap), work);
+ const gfp_t gfp = GFP_KERNEL | __GFP_RETRY_MAYFAIL | __GFP_NOWARN;
+ struct intel_engine_cs *engine = cap->rq->engine;
+ struct intel_gt_coredump *gt = cap->error->gt;
+ struct intel_engine_capture_vma *vma;
+
+ /* Compress all the objects attached to the request, slow! */
+ vma = intel_engine_coredump_add_request(gt->engine, cap->rq, gfp);
+ if (vma) {
+ struct i915_vma_compress *compress =
+ i915_vma_capture_prepare(gt);
+
+ intel_engine_coredump_add_vma(gt->engine, vma, compress);
+ i915_vma_capture_finish(gt, compress);
+ }
+
+ gt->simulated = gt->engine->simulated;
+ cap->error->simulated = gt->simulated;
+
+ /* Publish the error state, and announce it to the world */
+ i915_error_state_store(cap->error);
+ i915_gpu_coredump_put(cap->error);
+
+ /* Return this request and all that depend upon it for signaling */
+ execlists_unhold(engine, cap->rq);
+ i915_request_put(cap->rq);
+
+ kfree(cap);
+}
+
+static struct execlists_capture *capture_regs(struct intel_engine_cs *engine)
+{
+ const gfp_t gfp = GFP_ATOMIC | __GFP_NOWARN;
+ struct execlists_capture *cap;
+
+ cap = kmalloc(sizeof(*cap), gfp);
+ if (!cap)
+ return NULL;
+
+ cap->error = i915_gpu_coredump_alloc(engine->i915, gfp);
+ if (!cap->error)
+ goto err_cap;
+
+ cap->error->gt = intel_gt_coredump_alloc(engine->gt, gfp);
+ if (!cap->error->gt)
+ goto err_gpu;
+
+ cap->error->gt->engine = intel_engine_coredump_alloc(engine, gfp);
+ if (!cap->error->gt->engine)
+ goto err_gt;
+
+ cap->error->gt->engine->hung = true;
+
+ return cap;
+
+err_gt:
+ kfree(cap->error->gt);
+err_gpu:
+ kfree(cap->error);
+err_cap:
+ kfree(cap);
+ return NULL;
+}
+
+static struct i915_request *
+active_context(struct intel_engine_cs *engine, u32 ccid)
+{
+ const struct intel_engine_execlists * const el = &engine->execlists;
+ struct i915_request * const *port, *rq;
+
+ /*
+ * Use the most recent result from process_csb(), but just in case
+ * we trigger an error (via interrupt) before the first CS event has
+ * been written, peek at the next submission.
+ */
+
+ for (port = el->active; (rq = *port); port++) {
+ if (rq->context->lrc.ccid == ccid) {
+ ENGINE_TRACE(engine,
+ "ccid found at active:%zd\n",
+ port - el->active);
+ return rq;
+ }
+ }
+
+ for (port = el->pending; (rq = *port); port++) {
+ if (rq->context->lrc.ccid == ccid) {
+ ENGINE_TRACE(engine,
+ "ccid found at pending:%zd\n",
+ port - el->pending);
+ return rq;
+ }
+ }
+
+ ENGINE_TRACE(engine, "ccid:%x not found\n", ccid);
+ return NULL;
+}
+
+static u32 active_ccid(struct intel_engine_cs *engine)
+{
+ return ENGINE_READ_FW(engine, RING_EXECLIST_STATUS_HI);
+}
+
+static void execlists_capture(struct intel_engine_cs *engine)
+{
+ struct execlists_capture *cap;
+
+ if (!IS_ENABLED(CONFIG_DRM_I915_CAPTURE_ERROR))
+ return;
+
+ /*
+ * We need to _quickly_ capture the engine state before we reset.
+ * We are inside an atomic section (softirq) here and we are delaying
+ * the forced preemption event.
+ */
+ cap = capture_regs(engine);
+ if (!cap)
+ return;
+
+ spin_lock_irq(&engine->active.lock);
+ cap->rq = active_context(engine, active_ccid(engine));
+ if (cap->rq) {
+ cap->rq = active_request(cap->rq->context->timeline, cap->rq);
+ cap->rq = i915_request_get_rcu(cap->rq);
+ }
+ spin_unlock_irq(&engine->active.lock);
+ if (!cap->rq)
+ goto err_free;
+
+ /*
+ * Remove the request from the execlists queue, and take ownership
+ * of the request. We pass it to our worker who will _slowly_ compress
+ * all the pages the _user_ requested for debugging their batch, after
+ * which we return it to the queue for signaling.
+ *
+ * By removing them from the execlists queue, we also remove the
+ * requests from being processed by __unwind_incomplete_requests()
+ * during the intel_engine_reset(), and so they will *not* be replayed
+ * afterwards.
+ *
+ * Note that because we have not yet reset the engine at this point,
+ * it is possible for the request that we have identified as being
+ * guilty, did in fact complete and we will then hit an arbitration
+ * point allowing the outstanding preemption to succeed. The likelihood
+ * of that is very low (as capturing of the engine registers should be
+ * fast enough to run inside an irq-off atomic section!), so we will
+ * simply hold that request accountable for being non-preemptible
+ * long enough to force the reset.
+ */
+ if (!execlists_hold(engine, cap->rq))
+ goto err_rq;
+
+ INIT_WORK(&cap->work, execlists_capture_work);
+ schedule_work(&cap->work);
+ return;
+
+err_rq:
+ i915_request_put(cap->rq);
+err_free:
+ i915_gpu_coredump_put(cap->error);
+ kfree(cap);
+}
+
+static void execlists_reset(struct intel_engine_cs *engine, const char *msg)
+{
+ const unsigned int bit = I915_RESET_ENGINE + engine->id;
+ unsigned long *lock = &engine->gt->reset.flags;
+
+ if (!intel_has_reset_engine(engine->gt))
+ return;
+
+ if (test_and_set_bit(bit, lock))
+ return;
+
+ ENGINE_TRACE(engine, "reset for %s\n", msg);
+
+ /* Mark this tasklet as disabled to avoid waiting for it to complete */
+ tasklet_disable_nosync(&engine->execlists.tasklet);
+
+ ring_set_paused(engine, 1); /* Freeze the current request in place */
+ execlists_capture(engine);
+ intel_engine_reset(engine, msg);
+
+ tasklet_enable(&engine->execlists.tasklet);
+ clear_and_wake_up_bit(bit, lock);
+}
+
+static bool preempt_timeout(const struct intel_engine_cs *const engine)
+{
+ const struct timer_list *t = &engine->execlists.preempt;
+
+ if (!CONFIG_DRM_I915_PREEMPT_TIMEOUT)
+ return false;
+
+ if (!timer_expired(t))
+ return false;
+
+ return READ_ONCE(engine->execlists.pending[0]);
+}
+
+/*
+ * Check the unread Context Status Buffers and manage the submission of new
+ * contexts to the ELSP accordingly.
+ */
+static void execlists_submission_tasklet(unsigned long data)
+{
+ struct intel_engine_cs * const engine = (struct intel_engine_cs *)data;
+ bool timeout = preempt_timeout(engine);
+
+ process_csb(engine);
+
+ if (unlikely(READ_ONCE(engine->execlists.error_interrupt))) {
+ const char *msg;
+
+ /* Generate the error message in priority wrt to the user! */
+ if (engine->execlists.error_interrupt & GENMASK(15, 0))
+ msg = "CS error"; /* thrown by a user payload */
+ else if (engine->execlists.error_interrupt & ERROR_CSB)
+ msg = "invalid CSB event";
+ else
+ msg = "internal error";
+
+ engine->execlists.error_interrupt = 0;
+ execlists_reset(engine, msg);
+ }
+
+ if (!READ_ONCE(engine->execlists.pending[0]) || timeout) {
+ unsigned long flags;
+
+ spin_lock_irqsave(&engine->active.lock, flags);
+ __execlists_submission_tasklet(engine);
+ spin_unlock_irqrestore(&engine->active.lock, flags);
+
+ /* Recheck after serialising with direct-submission */
+ if (unlikely(timeout && preempt_timeout(engine))) {
+ cancel_timer(&engine->execlists.preempt);
+ execlists_reset(engine, "preemption time out");
+ }
+ }
+}
+
+static void __execlists_kick(struct intel_engine_execlists *execlists)
+{
+ /* Kick the tasklet for some interrupt coalescing and reset handling */
+ tasklet_hi_schedule(&execlists->tasklet);
+}
+
+#define execlists_kick(t, member) \
+ __execlists_kick(container_of(t, struct intel_engine_execlists, member))
+
+static void execlists_timeslice(struct timer_list *timer)
+{
+ execlists_kick(timer, timer);
+}
+
+static void execlists_preempt(struct timer_list *timer)
+{
+ execlists_kick(timer, preempt);
+}
+
+static void queue_request(struct intel_engine_cs *engine,
+ struct i915_request *rq)
+{
+ GEM_BUG_ON(!list_empty(&rq->sched.link));
+ list_add_tail(&rq->sched.link,
+ i915_sched_lookup_priolist(engine, rq_prio(rq)));
+ set_bit(I915_FENCE_FLAG_PQUEUE, &rq->fence.flags);
+}
+
+static void __submit_queue_imm(struct intel_engine_cs *engine)
+{
+ struct intel_engine_execlists * const execlists = &engine->execlists;
+
+ if (reset_in_progress(execlists))
+ return; /* defer until we restart the engine following reset */
+
+ __execlists_submission_tasklet(engine);
+}
+
+static void submit_queue(struct intel_engine_cs *engine,
+ const struct i915_request *rq)
+{
+ struct intel_engine_execlists *execlists = &engine->execlists;
+
+ if (rq_prio(rq) <= execlists->queue_priority_hint)
+ return;
+
+ execlists->queue_priority_hint = rq_prio(rq);
+ __submit_queue_imm(engine);
+}
+
+static bool ancestor_on_hold(const struct intel_engine_cs *engine,
+ const struct i915_request *rq)
+{
+ GEM_BUG_ON(i915_request_on_hold(rq));
+ return !list_empty(&engine->active.hold) && hold_request(rq);
+}
+
+static void flush_csb(struct intel_engine_cs *engine)
+{
+ struct intel_engine_execlists *el = &engine->execlists;
+
+ if (READ_ONCE(el->pending[0]) && tasklet_trylock(&el->tasklet)) {
+ if (!reset_in_progress(el))
+ process_csb(engine);
+ tasklet_unlock(&el->tasklet);
+ }
+}
+
+static void execlists_submit_request(struct i915_request *request)
+{
+ struct intel_engine_cs *engine = request->engine;
+ unsigned long flags;
+
+ /* Hopefully we clear execlists->pending[] to let us through */
+ flush_csb(engine);
+
+ /* Will be called from irq-context when using foreign fences. */
+ spin_lock_irqsave(&engine->active.lock, flags);
+
+ if (unlikely(ancestor_on_hold(engine, request))) {
+ RQ_TRACE(request, "ancestor on hold\n");
+ list_add_tail(&request->sched.link, &engine->active.hold);
+ i915_request_set_hold(request);
+ } else {
+ queue_request(engine, request);
+
+ GEM_BUG_ON(RB_EMPTY_ROOT(&engine->execlists.queue.rb_root));
+ GEM_BUG_ON(list_empty(&request->sched.link));
+
+ submit_queue(engine, request);
+ }
+
+ spin_unlock_irqrestore(&engine->active.lock, flags);
+}
+
+static void __execlists_context_fini(struct intel_context *ce)
+{
+ intel_ring_put(ce->ring);
+ i915_vma_put(ce->state);
+}
+
+static void execlists_context_destroy(struct kref *kref)
+{
+ struct intel_context *ce = container_of(kref, typeof(*ce), ref);
+
+ GEM_BUG_ON(!i915_active_is_idle(&ce->active));
+ GEM_BUG_ON(intel_context_is_pinned(ce));
+
+ if (ce->state)
+ __execlists_context_fini(ce);
+
+ intel_context_fini(ce);
+ intel_context_free(ce);
+}
+
+static void
+set_redzone(void *vaddr, const struct intel_engine_cs *engine)
+{
+ if (!IS_ENABLED(CONFIG_DRM_I915_DEBUG_GEM))
+ return;
+
+ vaddr += engine->context_size;
+
+ memset(vaddr, CONTEXT_REDZONE, I915_GTT_PAGE_SIZE);
+}
+
+static void
+check_redzone(const void *vaddr, const struct intel_engine_cs *engine)
+{
+ if (!IS_ENABLED(CONFIG_DRM_I915_DEBUG_GEM))
+ return;
+
+ vaddr += engine->context_size;
+
+ if (memchr_inv(vaddr, CONTEXT_REDZONE, I915_GTT_PAGE_SIZE))
+ drm_err_once(&engine->i915->drm,
+ "%s context redzone overwritten!\n",
+ engine->name);
+}
+
+static void execlists_context_unpin(struct intel_context *ce)
+{
+ check_redzone((void *)ce->lrc_reg_state - LRC_STATE_OFFSET,
+ ce->engine);
+}
+
+static void execlists_context_post_unpin(struct intel_context *ce)
+{
+ i915_gem_object_unpin_map(ce->state->obj);
+}
+
+static u32 *
+gen12_emit_timestamp_wa(const struct intel_context *ce, u32 *cs)
+{
+ *cs++ = MI_LOAD_REGISTER_MEM_GEN8 |
+ MI_SRM_LRM_GLOBAL_GTT |
+ MI_LRI_LRM_CS_MMIO;
+ *cs++ = i915_mmio_reg_offset(GEN8_RING_CS_GPR(0, 0));
+ *cs++ = i915_ggtt_offset(ce->state) + LRC_STATE_OFFSET +
+ CTX_TIMESTAMP * sizeof(u32);
+ *cs++ = 0;
+
+ *cs++ = MI_LOAD_REGISTER_REG |
+ MI_LRR_SOURCE_CS_MMIO |
+ MI_LRI_LRM_CS_MMIO;
+ *cs++ = i915_mmio_reg_offset(GEN8_RING_CS_GPR(0, 0));
+ *cs++ = i915_mmio_reg_offset(RING_CTX_TIMESTAMP(0));
+
+ *cs++ = MI_LOAD_REGISTER_REG |
+ MI_LRR_SOURCE_CS_MMIO |
+ MI_LRI_LRM_CS_MMIO;
+ *cs++ = i915_mmio_reg_offset(GEN8_RING_CS_GPR(0, 0));
+ *cs++ = i915_mmio_reg_offset(RING_CTX_TIMESTAMP(0));
+
+ return cs;
+}
+
+static u32 *
+gen12_emit_restore_scratch(const struct intel_context *ce, u32 *cs)
+{
+ GEM_BUG_ON(lrc_ring_gpr0(ce->engine) == -1);
+
+ *cs++ = MI_LOAD_REGISTER_MEM_GEN8 |
+ MI_SRM_LRM_GLOBAL_GTT |
+ MI_LRI_LRM_CS_MMIO;
+ *cs++ = i915_mmio_reg_offset(GEN8_RING_CS_GPR(0, 0));
+ *cs++ = i915_ggtt_offset(ce->state) + LRC_STATE_OFFSET +
+ (lrc_ring_gpr0(ce->engine) + 1) * sizeof(u32);
+ *cs++ = 0;
+
+ return cs;
+}
+
+static u32 *
+gen12_emit_cmd_buf_wa(const struct intel_context *ce, u32 *cs)
+{
+ GEM_BUG_ON(lrc_ring_cmd_buf_cctl(ce->engine) == -1);
+
+ *cs++ = MI_LOAD_REGISTER_MEM_GEN8 |
+ MI_SRM_LRM_GLOBAL_GTT |
+ MI_LRI_LRM_CS_MMIO;
+ *cs++ = i915_mmio_reg_offset(GEN8_RING_CS_GPR(0, 0));
+ *cs++ = i915_ggtt_offset(ce->state) + LRC_STATE_OFFSET +
+ (lrc_ring_cmd_buf_cctl(ce->engine) + 1) * sizeof(u32);
+ *cs++ = 0;
+
+ *cs++ = MI_LOAD_REGISTER_REG |
+ MI_LRR_SOURCE_CS_MMIO |
+ MI_LRI_LRM_CS_MMIO;
+ *cs++ = i915_mmio_reg_offset(GEN8_RING_CS_GPR(0, 0));
+ *cs++ = i915_mmio_reg_offset(RING_CMD_BUF_CCTL(0));
+
+ return cs;
+}
+
+static u32 *
+gen12_emit_indirect_ctx_rcs(const struct intel_context *ce, u32 *cs)
+{
+ cs = gen12_emit_timestamp_wa(ce, cs);
+ cs = gen12_emit_cmd_buf_wa(ce, cs);
+ cs = gen12_emit_restore_scratch(ce, cs);
+
+ return cs;
+}
+
+static u32 *
+gen12_emit_indirect_ctx_xcs(const struct intel_context *ce, u32 *cs)
+{
+ cs = gen12_emit_timestamp_wa(ce, cs);
+ cs = gen12_emit_restore_scratch(ce, cs);
+
+ return cs;
+}
+
+static inline u32 context_wa_bb_offset(const struct intel_context *ce)
+{
+ return PAGE_SIZE * ce->wa_bb_page;
+}
+
+static u32 *context_indirect_bb(const struct intel_context *ce)
+{
+ void *ptr;
+
+ GEM_BUG_ON(!ce->wa_bb_page);
+
+ ptr = ce->lrc_reg_state;
+ ptr -= LRC_STATE_OFFSET; /* back to start of context image */
+ ptr += context_wa_bb_offset(ce);
+
+ return ptr;
+}
+
+static void
+setup_indirect_ctx_bb(const struct intel_context *ce,
+ const struct intel_engine_cs *engine,
+ u32 *(*emit)(const struct intel_context *, u32 *))
+{
+ u32 * const start = context_indirect_bb(ce);
+ u32 *cs;
+
+ cs = emit(ce, start);
+ GEM_BUG_ON(cs - start > I915_GTT_PAGE_SIZE / sizeof(*cs));
+ while ((unsigned long)cs % CACHELINE_BYTES)
+ *cs++ = MI_NOOP;
+
+ lrc_ring_setup_indirect_ctx(ce->lrc_reg_state, engine,
+ i915_ggtt_offset(ce->state) +
+ context_wa_bb_offset(ce),
+ (cs - start) * sizeof(*cs));
+}
+
+static void
+__execlists_update_reg_state(const struct intel_context *ce,
+ const struct intel_engine_cs *engine,
+ u32 head)
+{
+ struct intel_ring *ring = ce->ring;
+ u32 *regs = ce->lrc_reg_state;
+
+ GEM_BUG_ON(!intel_ring_offset_valid(ring, head));
+ GEM_BUG_ON(!intel_ring_offset_valid(ring, ring->tail));
+
+ regs[CTX_RING_START] = i915_ggtt_offset(ring->vma);
+ regs[CTX_RING_HEAD] = head;
+ regs[CTX_RING_TAIL] = ring->tail;
+ regs[CTX_RING_CTL] = RING_CTL_SIZE(ring->size) | RING_VALID;
+
+ /* RPCS */
+ if (engine->class == RENDER_CLASS) {
+ regs[CTX_R_PWR_CLK_STATE] =
+ intel_sseu_make_rpcs(engine->gt, &ce->sseu);
+
+ i915_oa_init_reg_state(ce, engine);
+ }
+
+ if (ce->wa_bb_page) {
+ u32 *(*fn)(const struct intel_context *ce, u32 *cs);
+
+ fn = gen12_emit_indirect_ctx_xcs;
+ if (ce->engine->class == RENDER_CLASS)
+ fn = gen12_emit_indirect_ctx_rcs;
+
+ /* Mutually exclusive wrt to global indirect bb */
+ GEM_BUG_ON(engine->wa_ctx.indirect_ctx.size);
+ setup_indirect_ctx_bb(ce, engine, fn);
+ }
+}
+
+static int
+execlists_context_pre_pin(struct intel_context *ce,
+ struct i915_gem_ww_ctx *ww, void **vaddr)
+{
+ GEM_BUG_ON(!ce->state);
+ GEM_BUG_ON(!i915_vma_is_pinned(ce->state));
+
+ *vaddr = i915_gem_object_pin_map(ce->state->obj,
+ i915_coherent_map_type(ce->engine->i915) |
+ I915_MAP_OVERRIDE);
+
+ return PTR_ERR_OR_ZERO(*vaddr);
+}
+
+static int
+__execlists_context_pin(struct intel_context *ce,
+ struct intel_engine_cs *engine,
+ void *vaddr)
+{
+ ce->lrc.lrca = lrc_descriptor(ce, engine) | CTX_DESC_FORCE_RESTORE;
+ ce->lrc_reg_state = vaddr + LRC_STATE_OFFSET;
+ __execlists_update_reg_state(ce, engine, ce->ring->tail);
+
+ return 0;
+}
+
+static int execlists_context_pin(struct intel_context *ce, void *vaddr)
+{
+ return __execlists_context_pin(ce, ce->engine, vaddr);
+}
+
+static int execlists_context_alloc(struct intel_context *ce)
+{
+ return __execlists_context_alloc(ce, ce->engine);
+}
+
+static void execlists_context_reset(struct intel_context *ce)
+{
+ CE_TRACE(ce, "reset\n");
+ GEM_BUG_ON(!intel_context_is_pinned(ce));
+
+ intel_ring_reset(ce->ring, ce->ring->emit);
+
+ /* Scrub away the garbage */
+ execlists_init_reg_state(ce->lrc_reg_state,
+ ce, ce->engine, ce->ring, true);
+ __execlists_update_reg_state(ce, ce->engine, ce->ring->tail);
+
+ ce->lrc.desc |= CTX_DESC_FORCE_RESTORE;
+}
+
+static const struct intel_context_ops execlists_context_ops = {
+ .alloc = execlists_context_alloc,
+
+ .pre_pin = execlists_context_pre_pin,
+ .pin = execlists_context_pin,
+ .unpin = execlists_context_unpin,
+ .post_unpin = execlists_context_post_unpin,
+
+ .enter = intel_context_enter_engine,
+ .exit = intel_context_exit_engine,
+
+ .reset = execlists_context_reset,
+ .destroy = execlists_context_destroy,
+};
+
+static u32 hwsp_offset(const struct i915_request *rq)
+{
+ const struct intel_timeline_cacheline *cl;
+
+ /* Before the request is executed, the timeline/cachline is fixed */
+
+ cl = rcu_dereference_protected(rq->hwsp_cacheline, 1);
+ if (cl)
+ return cl->ggtt_offset;
+
+ return rcu_dereference_protected(rq->timeline, 1)->hwsp_offset;
+}
+
+static int gen8_emit_init_breadcrumb(struct i915_request *rq)
+{
+ u32 *cs;
+
+ GEM_BUG_ON(i915_request_has_initial_breadcrumb(rq));
+ if (!i915_request_timeline(rq)->has_initial_breadcrumb)
+ return 0;
+
+ cs = intel_ring_begin(rq, 6);
+ if (IS_ERR(cs))
+ return PTR_ERR(cs);
+
+ /*
+ * Check if we have been preempted before we even get started.
+ *
+ * After this point i915_request_started() reports true, even if
+ * we get preempted and so are no longer running.
+ */
+ *cs++ = MI_ARB_CHECK;
+ *cs++ = MI_NOOP;
+
+ *cs++ = MI_STORE_DWORD_IMM_GEN4 | MI_USE_GGTT;
+ *cs++ = hwsp_offset(rq);
+ *cs++ = 0;
+ *cs++ = rq->fence.seqno - 1;
+
+ intel_ring_advance(rq, cs);
+
+ /* Record the updated position of the request's payload */
+ rq->infix = intel_ring_offset(rq, cs);
+
+ __set_bit(I915_FENCE_FLAG_INITIAL_BREADCRUMB, &rq->fence.flags);
+
+ return 0;
+}
+
+static int emit_pdps(struct i915_request *rq)
+{
+ const struct intel_engine_cs * const engine = rq->engine;
+ struct i915_ppgtt * const ppgtt = i915_vm_to_ppgtt(rq->context->vm);
+ int err, i;
+ u32 *cs;
+
+ GEM_BUG_ON(intel_vgpu_active(rq->engine->i915));
+
+ /*
+ * Beware ye of the dragons, this sequence is magic!
+ *
+ * Small changes to this sequence can cause anything from
+ * GPU hangs to forcewake errors and machine lockups!
+ */
+
+ /* Flush any residual operations from the context load */
+ err = engine->emit_flush(rq, EMIT_FLUSH);
+ if (err)
+ return err;
+
+ /* Magic required to prevent forcewake errors! */
+ err = engine->emit_flush(rq, EMIT_INVALIDATE);
+ if (err)
+ return err;
+
+ cs = intel_ring_begin(rq, 4 * GEN8_3LVL_PDPES + 2);
+ if (IS_ERR(cs))
+ return PTR_ERR(cs);
+
+ /* Ensure the LRI have landed before we invalidate & continue */
+ *cs++ = MI_LOAD_REGISTER_IMM(2 * GEN8_3LVL_PDPES) | MI_LRI_FORCE_POSTED;
+ for (i = GEN8_3LVL_PDPES; i--; ) {
+ const dma_addr_t pd_daddr = i915_page_dir_dma_addr(ppgtt, i);
+ u32 base = engine->mmio_base;
+
+ *cs++ = i915_mmio_reg_offset(GEN8_RING_PDP_UDW(base, i));
+ *cs++ = upper_32_bits(pd_daddr);
+ *cs++ = i915_mmio_reg_offset(GEN8_RING_PDP_LDW(base, i));
+ *cs++ = lower_32_bits(pd_daddr);
+ }
+ *cs++ = MI_NOOP;
+
+ intel_ring_advance(rq, cs);
+
+ return 0;
+}
+
+static int execlists_request_alloc(struct i915_request *request)
+{
+ int ret;
+
+ GEM_BUG_ON(!intel_context_is_pinned(request->context));
+
+ /*
+ * Flush enough space to reduce the likelihood of waiting after
+ * we start building the request - in which case we will just
+ * have to repeat work.
+ */
+ request->reserved_space += EXECLISTS_REQUEST_SIZE;
+
+ /*
+ * Note that after this point, we have committed to using
+ * this request as it is being used to both track the
+ * state of engine initialisation and liveness of the
+ * golden renderstate above. Think twice before you try
+ * to cancel/unwind this request now.
+ */
+
+ if (!i915_vm_is_4lvl(request->context->vm)) {
+ ret = emit_pdps(request);
+ if (ret)
+ return ret;
+ }
+
+ /* Unconditionally invalidate GPU caches and TLBs. */
+ ret = request->engine->emit_flush(request, EMIT_INVALIDATE);
+ if (ret)
+ return ret;
+
+ request->reserved_space -= EXECLISTS_REQUEST_SIZE;
+ return 0;
+}
+
+/*
+ * In this WA we need to set GEN8_L3SQCREG4[21:21] and reset it after
+ * PIPE_CONTROL instruction. This is required for the flush to happen correctly
+ * but there is a slight complication as this is applied in WA batch where the
+ * values are only initialized once so we cannot take register value at the
+ * beginning and reuse it further; hence we save its value to memory, upload a
+ * constant value with bit21 set and then we restore it back with the saved value.
+ * To simplify the WA, a constant value is formed by using the default value
+ * of this register. This shouldn't be a problem because we are only modifying
+ * it for a short period and this batch in non-premptible. We can ofcourse
+ * use additional instructions that read the actual value of the register
+ * at that time and set our bit of interest but it makes the WA complicated.
+ *
+ * This WA is also required for Gen9 so extracting as a function avoids
+ * code duplication.
+ */
+static u32 *
+gen8_emit_flush_coherentl3_wa(struct intel_engine_cs *engine, u32 *batch)
+{
+ /* NB no one else is allowed to scribble over scratch + 256! */
+ *batch++ = MI_STORE_REGISTER_MEM_GEN8 | MI_SRM_LRM_GLOBAL_GTT;
+ *batch++ = i915_mmio_reg_offset(GEN8_L3SQCREG4);
+ *batch++ = intel_gt_scratch_offset(engine->gt,
+ INTEL_GT_SCRATCH_FIELD_COHERENTL3_WA);
+ *batch++ = 0;
+
+ *batch++ = MI_LOAD_REGISTER_IMM(1);
+ *batch++ = i915_mmio_reg_offset(GEN8_L3SQCREG4);
+ *batch++ = 0x40400000 | GEN8_LQSC_FLUSH_COHERENT_LINES;
+
+ batch = gen8_emit_pipe_control(batch,
+ PIPE_CONTROL_CS_STALL |
+ PIPE_CONTROL_DC_FLUSH_ENABLE,
+ 0);
+
+ *batch++ = MI_LOAD_REGISTER_MEM_GEN8 | MI_SRM_LRM_GLOBAL_GTT;
+ *batch++ = i915_mmio_reg_offset(GEN8_L3SQCREG4);
+ *batch++ = intel_gt_scratch_offset(engine->gt,
+ INTEL_GT_SCRATCH_FIELD_COHERENTL3_WA);
+ *batch++ = 0;
+
+ return batch;
+}
+
+/*
+ * Typically we only have one indirect_ctx and per_ctx batch buffer which are
+ * initialized at the beginning and shared across all contexts but this field
+ * helps us to have multiple batches at different offsets and select them based
+ * on a criteria. At the moment this batch always start at the beginning of the page
+ * and at this point we don't have multiple wa_ctx batch buffers.
+ *
+ * The number of WA applied are not known at the beginning; we use this field
+ * to return the no of DWORDS written.
+ *
+ * It is to be noted that this batch does not contain MI_BATCH_BUFFER_END
+ * so it adds NOOPs as padding to make it cacheline aligned.
+ * MI_BATCH_BUFFER_END will be added to perctx batch and both of them together
+ * makes a complete batch buffer.
+ */
+static u32 *gen8_init_indirectctx_bb(struct intel_engine_cs *engine, u32 *batch)
+{
+ /* WaDisableCtxRestoreArbitration:bdw,chv */
+ *batch++ = MI_ARB_ON_OFF | MI_ARB_DISABLE;
+
+ /* WaFlushCoherentL3CacheLinesAtContextSwitch:bdw */
+ if (IS_BROADWELL(engine->i915))
+ batch = gen8_emit_flush_coherentl3_wa(engine, batch);
+
+ /* WaClearSlmSpaceAtContextSwitch:bdw,chv */
+ /* Actual scratch location is at 128 bytes offset */
+ batch = gen8_emit_pipe_control(batch,
+ PIPE_CONTROL_FLUSH_L3 |
+ PIPE_CONTROL_STORE_DATA_INDEX |
+ PIPE_CONTROL_CS_STALL |
+ PIPE_CONTROL_QW_WRITE,
+ LRC_PPHWSP_SCRATCH_ADDR);
+
+ *batch++ = MI_ARB_ON_OFF | MI_ARB_ENABLE;
+
+ /* Pad to end of cacheline */
+ while ((unsigned long)batch % CACHELINE_BYTES)
+ *batch++ = MI_NOOP;
+
+ /*
+ * MI_BATCH_BUFFER_END is not required in Indirect ctx BB because
+ * execution depends on the length specified in terms of cache lines
+ * in the register CTX_RCS_INDIRECT_CTX
+ */
+
+ return batch;
+}
+
+struct lri {
+ i915_reg_t reg;
+ u32 value;
+};
+
+static u32 *emit_lri(u32 *batch, const struct lri *lri, unsigned int count)
+{
+ GEM_BUG_ON(!count || count > 63);
+
+ *batch++ = MI_LOAD_REGISTER_IMM(count);
+ do {
+ *batch++ = i915_mmio_reg_offset(lri->reg);
+ *batch++ = lri->value;
+ } while (lri++, --count);
+ *batch++ = MI_NOOP;
+
+ return batch;
+}
+
+static u32 *gen9_init_indirectctx_bb(struct intel_engine_cs *engine, u32 *batch)
+{
+ static const struct lri lri[] = {
+ /* WaDisableGatherAtSetShaderCommonSlice:skl,bxt,kbl,glk */
+ {
+ COMMON_SLICE_CHICKEN2,
+ __MASKED_FIELD(GEN9_DISABLE_GATHER_AT_SET_SHADER_COMMON_SLICE,
+ 0),
+ },
+
+ /* BSpec: 11391 */
+ {
+ FF_SLICE_CHICKEN,
+ __MASKED_FIELD(FF_SLICE_CHICKEN_CL_PROVOKING_VERTEX_FIX,
+ FF_SLICE_CHICKEN_CL_PROVOKING_VERTEX_FIX),
+ },
+
+ /* BSpec: 11299 */
+ {
+ _3D_CHICKEN3,
+ __MASKED_FIELD(_3D_CHICKEN_SF_PROVOKING_VERTEX_FIX,
+ _3D_CHICKEN_SF_PROVOKING_VERTEX_FIX),
+ }
+ };
+
+ *batch++ = MI_ARB_ON_OFF | MI_ARB_DISABLE;
+
+ /* WaFlushCoherentL3CacheLinesAtContextSwitch:skl,bxt,glk */
+ batch = gen8_emit_flush_coherentl3_wa(engine, batch);
+
+ /* WaClearSlmSpaceAtContextSwitch:skl,bxt,kbl,glk,cfl */
+ batch = gen8_emit_pipe_control(batch,
+ PIPE_CONTROL_FLUSH_L3 |
+ PIPE_CONTROL_STORE_DATA_INDEX |
+ PIPE_CONTROL_CS_STALL |
+ PIPE_CONTROL_QW_WRITE,
+ LRC_PPHWSP_SCRATCH_ADDR);
+
+ batch = emit_lri(batch, lri, ARRAY_SIZE(lri));
+
+ /* WaMediaPoolStateCmdInWABB:bxt,glk */
+ if (HAS_POOLED_EU(engine->i915)) {
+ /*
+ * EU pool configuration is setup along with golden context
+ * during context initialization. This value depends on
+ * device type (2x6 or 3x6) and needs to be updated based
+ * on which subslice is disabled especially for 2x6
+ * devices, however it is safe to load default
+ * configuration of 3x6 device instead of masking off
+ * corresponding bits because HW ignores bits of a disabled
+ * subslice and drops down to appropriate config. Please
+ * see render_state_setup() in i915_gem_render_state.c for
+ * possible configurations, to avoid duplication they are
+ * not shown here again.
+ */
+ *batch++ = GEN9_MEDIA_POOL_STATE;
+ *batch++ = GEN9_MEDIA_POOL_ENABLE;
+ *batch++ = 0x00777000;
+ *batch++ = 0;
+ *batch++ = 0;
+ *batch++ = 0;
+ }
+
+ *batch++ = MI_ARB_ON_OFF | MI_ARB_ENABLE;
+
+ /* Pad to end of cacheline */
+ while ((unsigned long)batch % CACHELINE_BYTES)
+ *batch++ = MI_NOOP;
+
+ return batch;
+}
+
+static u32 *
+gen10_init_indirectctx_bb(struct intel_engine_cs *engine, u32 *batch)
+{
+ int i;
+
+ /*
+ * WaPipeControlBefore3DStateSamplePattern: cnl
+ *
+ * Ensure the engine is idle prior to programming a
+ * 3DSTATE_SAMPLE_PATTERN during a context restore.
+ */
+ batch = gen8_emit_pipe_control(batch,
+ PIPE_CONTROL_CS_STALL,
+ 0);
+ /*
+ * WaPipeControlBefore3DStateSamplePattern says we need 4 dwords for
+ * the PIPE_CONTROL followed by 12 dwords of 0x0, so 16 dwords in
+ * total. However, a PIPE_CONTROL is 6 dwords long, not 4, which is
+ * confusing. Since gen8_emit_pipe_control() already advances the
+ * batch by 6 dwords, we advance the other 10 here, completing a
+ * cacheline. It's not clear if the workaround requires this padding
+ * before other commands, or if it's just the regular padding we would
+ * already have for the workaround bb, so leave it here for now.
+ */
+ for (i = 0; i < 10; i++)
+ *batch++ = MI_NOOP;
+
+ /* Pad to end of cacheline */
+ while ((unsigned long)batch % CACHELINE_BYTES)
+ *batch++ = MI_NOOP;
+
+ return batch;
+}
+
+#define CTX_WA_BB_OBJ_SIZE (PAGE_SIZE)
+
+static int lrc_setup_wa_ctx(struct intel_engine_cs *engine)
+{
+ struct drm_i915_gem_object *obj;
+ struct i915_vma *vma;
+ int err;
+
+ obj = i915_gem_object_create_shmem(engine->i915, CTX_WA_BB_OBJ_SIZE);
+ if (IS_ERR(obj))
+ return PTR_ERR(obj);
+
+ vma = i915_vma_instance(obj, &engine->gt->ggtt->vm, NULL);
+ if (IS_ERR(vma)) {
+ err = PTR_ERR(vma);
+ goto err;
+ }
+
+ err = i915_ggtt_pin(vma, NULL, 0, PIN_HIGH);
+ if (err)
+ goto err;
+
+ engine->wa_ctx.vma = vma;
+ return 0;
+
+err:
+ i915_gem_object_put(obj);
+ return err;
+}
+
+static void lrc_destroy_wa_ctx(struct intel_engine_cs *engine)
+{
+ i915_vma_unpin_and_release(&engine->wa_ctx.vma, 0);
+}
+
+typedef u32 *(*wa_bb_func_t)(struct intel_engine_cs *engine, u32 *batch);
+
+static int intel_init_workaround_bb(struct intel_engine_cs *engine)
+{
+ struct i915_ctx_workarounds *wa_ctx = &engine->wa_ctx;
+ struct i915_wa_ctx_bb *wa_bb[2] = { &wa_ctx->indirect_ctx,
+ &wa_ctx->per_ctx };
+ wa_bb_func_t wa_bb_fn[2];
+ void *batch, *batch_ptr;
+ unsigned int i;
+ int ret;
+
+ if (engine->class != RENDER_CLASS)
+ return 0;
+
+ switch (INTEL_GEN(engine->i915)) {
+ case 12:
+ case 11:
+ return 0;
+ case 10:
+ wa_bb_fn[0] = gen10_init_indirectctx_bb;
+ wa_bb_fn[1] = NULL;
+ break;
+ case 9:
+ wa_bb_fn[0] = gen9_init_indirectctx_bb;
+ wa_bb_fn[1] = NULL;
+ break;
+ case 8:
+ wa_bb_fn[0] = gen8_init_indirectctx_bb;
+ wa_bb_fn[1] = NULL;
+ break;
+ default:
+ MISSING_CASE(INTEL_GEN(engine->i915));
+ return 0;
+ }
+
+ ret = lrc_setup_wa_ctx(engine);
+ if (ret) {
+ drm_dbg(&engine->i915->drm,
+ "Failed to setup context WA page: %d\n", ret);
+ return ret;
+ }
+
+ batch = i915_gem_object_pin_map(wa_ctx->vma->obj, I915_MAP_WB);
+
+ /*
+ * Emit the two workaround batch buffers, recording the offset from the
+ * start of the workaround batch buffer object for each and their
+ * respective sizes.
+ */
+ batch_ptr = batch;
+ for (i = 0; i < ARRAY_SIZE(wa_bb_fn); i++) {
+ wa_bb[i]->offset = batch_ptr - batch;
+ if (GEM_DEBUG_WARN_ON(!IS_ALIGNED(wa_bb[i]->offset,
+ CACHELINE_BYTES))) {
+ ret = -EINVAL;
+ break;
+ }
+ if (wa_bb_fn[i])
+ batch_ptr = wa_bb_fn[i](engine, batch_ptr);
+ wa_bb[i]->size = batch_ptr - (batch + wa_bb[i]->offset);
+ }
+ GEM_BUG_ON(batch_ptr - batch > CTX_WA_BB_OBJ_SIZE);
+
+ __i915_gem_object_flush_map(wa_ctx->vma->obj, 0, batch_ptr - batch);
+ __i915_gem_object_release_map(wa_ctx->vma->obj);
+ if (ret)
+ lrc_destroy_wa_ctx(engine);
+
+ return ret;
+}
+
+static void reset_csb_pointers(struct intel_engine_cs *engine)
+{
+ struct intel_engine_execlists * const execlists = &engine->execlists;
+ const unsigned int reset_value = execlists->csb_size - 1;
+
+ ring_set_paused(engine, 0);
+
+ /*
+ * Sometimes Icelake forgets to reset its pointers on a GPU reset.
+ * Bludgeon them with a mmio update to be sure.
+ */
+ ENGINE_WRITE(engine, RING_CONTEXT_STATUS_PTR,
+ 0xffff << 16 | reset_value << 8 | reset_value);
+ ENGINE_POSTING_READ(engine, RING_CONTEXT_STATUS_PTR);
+
+ /*
+ * After a reset, the HW starts writing into CSB entry [0]. We
+ * therefore have to set our HEAD pointer back one entry so that
+ * the *first* entry we check is entry 0. To complicate this further,
+ * as we don't wait for the first interrupt after reset, we have to
+ * fake the HW write to point back to the last entry so that our
+ * inline comparison of our cached head position against the last HW
+ * write works even before the first interrupt.
+ */
+ execlists->csb_head = reset_value;
+ WRITE_ONCE(*execlists->csb_write, reset_value);
+ wmb(); /* Make sure this is visible to HW (paranoia?) */
+
+ /* Check that the GPU does indeed update the CSB entries! */
+ memset(execlists->csb_status, -1, (reset_value + 1) * sizeof(u64));
+ invalidate_csb_entries(&execlists->csb_status[0],
+ &execlists->csb_status[reset_value]);
+
+ /* Once more for luck and our trusty paranoia */
+ ENGINE_WRITE(engine, RING_CONTEXT_STATUS_PTR,
+ 0xffff << 16 | reset_value << 8 | reset_value);
+ ENGINE_POSTING_READ(engine, RING_CONTEXT_STATUS_PTR);
+
+ GEM_BUG_ON(READ_ONCE(*execlists->csb_write) != reset_value);
+}
+
+static void execlists_sanitize(struct intel_engine_cs *engine)
+{
+ GEM_BUG_ON(execlists_active(&engine->execlists));
+
+ /*
+ * Poison residual state on resume, in case the suspend didn't!
+ *
+ * We have to assume that across suspend/resume (or other loss
+ * of control) that the contents of our pinned buffers has been
+ * lost, replaced by garbage. Since this doesn't always happen,
+ * let's poison such state so that we more quickly spot when
+ * we falsely assume it has been preserved.
+ */
+ if (IS_ENABLED(CONFIG_DRM_I915_DEBUG_GEM))
+ memset(engine->status_page.addr, POISON_INUSE, PAGE_SIZE);
+
+ reset_csb_pointers(engine);
+
+ /*
+ * The kernel_context HWSP is stored in the status_page. As above,
+ * that may be lost on resume/initialisation, and so we need to
+ * reset the value in the HWSP.
+ */
+ intel_timeline_reset_seqno(engine->kernel_context->timeline);
+
+ /* And scrub the dirty cachelines for the HWSP */
+ clflush_cache_range(engine->status_page.addr, PAGE_SIZE);
+}
+
+static void enable_error_interrupt(struct intel_engine_cs *engine)
+{
+ u32 status;
+
+ engine->execlists.error_interrupt = 0;
+ ENGINE_WRITE(engine, RING_EMR, ~0u);
+ ENGINE_WRITE(engine, RING_EIR, ~0u); /* clear all existing errors */
+
+ status = ENGINE_READ(engine, RING_ESR);
+ if (unlikely(status)) {
+ drm_err(&engine->i915->drm,
+ "engine '%s' resumed still in error: %08x\n",
+ engine->name, status);
+ __intel_gt_reset(engine->gt, engine->mask);
+ }
+
+ /*
+ * On current gen8+, we have 2 signals to play with
+ *
+ * - I915_ERROR_INSTUCTION (bit 0)
+ *
+ * Generate an error if the command parser encounters an invalid
+ * instruction
+ *
+ * This is a fatal error.
+ *
+ * - CP_PRIV (bit 2)
+ *
+ * Generate an error on privilege violation (where the CP replaces
+ * the instruction with a no-op). This also fires for writes into
+ * read-only scratch pages.
+ *
+ * This is a non-fatal error, parsing continues.
+ *
+ * * there are a few others defined for odd HW that we do not use
+ *
+ * Since CP_PRIV fires for cases where we have chosen to ignore the
+ * error (as the HW is validating and suppressing the mistakes), we
+ * only unmask the instruction error bit.
+ */
+ ENGINE_WRITE(engine, RING_EMR, ~I915_ERROR_INSTRUCTION);
+}
+
+static void enable_execlists(struct intel_engine_cs *engine)
+{
+ u32 mode;
+
+ assert_forcewakes_active(engine->uncore, FORCEWAKE_ALL);
+
+ intel_engine_set_hwsp_writemask(engine, ~0u); /* HWSTAM */
+
+ if (INTEL_GEN(engine->i915) >= 11)
+ mode = _MASKED_BIT_ENABLE(GEN11_GFX_DISABLE_LEGACY_MODE);
+ else
+ mode = _MASKED_BIT_ENABLE(GFX_RUN_LIST_ENABLE);
+ ENGINE_WRITE_FW(engine, RING_MODE_GEN7, mode);
+
+ ENGINE_WRITE_FW(engine, RING_MI_MODE, _MASKED_BIT_DISABLE(STOP_RING));
+
+ ENGINE_WRITE_FW(engine,
+ RING_HWS_PGA,
+ i915_ggtt_offset(engine->status_page.vma));
+ ENGINE_POSTING_READ(engine, RING_HWS_PGA);
+
+ enable_error_interrupt(engine);
+
+ engine->context_tag = GENMASK(BITS_PER_LONG - 2, 0);
+}
+
+static bool unexpected_starting_state(struct intel_engine_cs *engine)
+{
+ bool unexpected = false;
+
+ if (ENGINE_READ_FW(engine, RING_MI_MODE) & STOP_RING) {
+ drm_dbg(&engine->i915->drm,
+ "STOP_RING still set in RING_MI_MODE\n");
+ unexpected = true;
+ }
+
+ return unexpected;
+}
+
+static int execlists_resume(struct intel_engine_cs *engine)
+{
+ intel_mocs_init_engine(engine);
+
+ intel_breadcrumbs_reset(engine->breadcrumbs);
+
+ if (GEM_SHOW_DEBUG() && unexpected_starting_state(engine)) {
+ struct drm_printer p = drm_debug_printer(__func__);
+
+ intel_engine_dump(engine, &p, NULL);
+ }
+
+ enable_execlists(engine);
+
+ return 0;
+}
+
+static void execlists_reset_prepare(struct intel_engine_cs *engine)
+{
+ struct intel_engine_execlists * const execlists = &engine->execlists;
+ unsigned long flags;
+
+ ENGINE_TRACE(engine, "depth<-%d\n",
+ atomic_read(&execlists->tasklet.count));
+
+ /*
+ * Prevent request submission to the hardware until we have
+ * completed the reset in i915_gem_reset_finish(). If a request
+ * is completed by one engine, it may then queue a request
+ * to a second via its execlists->tasklet *just* as we are
+ * calling engine->resume() and also writing the ELSP.
+ * Turning off the execlists->tasklet until the reset is over
+ * prevents the race.
+ */
+ __tasklet_disable_sync_once(&execlists->tasklet);
+ GEM_BUG_ON(!reset_in_progress(execlists));
+
+ /* And flush any current direct submission. */
+ spin_lock_irqsave(&engine->active.lock, flags);
+ spin_unlock_irqrestore(&engine->active.lock, flags);
+
+ /*
+ * We stop engines, otherwise we might get failed reset and a
+ * dead gpu (on elk). Also as modern gpu as kbl can suffer
+ * from system hang if batchbuffer is progressing when
+ * the reset is issued, regardless of READY_TO_RESET ack.
+ * Thus assume it is best to stop engines on all gens
+ * where we have a gpu reset.
+ *
+ * WaKBLVECSSemaphoreWaitPoll:kbl (on ALL_ENGINES)
+ *
+ * FIXME: Wa for more modern gens needs to be validated
+ */
+ ring_set_paused(engine, 1);
+ intel_engine_stop_cs(engine);
+
+ engine->execlists.reset_ccid = active_ccid(engine);
+}
+
+static void __reset_stop_ring(u32 *regs, const struct intel_engine_cs *engine)
+{
+ int x;
+
+ x = lrc_ring_mi_mode(engine);
+ if (x != -1) {
+ regs[x + 1] &= ~STOP_RING;
+ regs[x + 1] |= STOP_RING << 16;
+ }
+}
+
+static void __execlists_reset_reg_state(const struct intel_context *ce,
+ const struct intel_engine_cs *engine)
+{
+ u32 *regs = ce->lrc_reg_state;
+
+ __reset_stop_ring(regs, engine);
+}
+
+static void __execlists_reset(struct intel_engine_cs *engine, bool stalled)
+{
+ struct intel_engine_execlists * const execlists = &engine->execlists;
+ struct intel_context *ce;
+ struct i915_request *rq;
+ u32 head;
+
+ mb(); /* paranoia: read the CSB pointers from after the reset */
+ clflush(execlists->csb_write);
+ mb();
+
+ process_csb(engine); /* drain preemption events */
+
+ /* Following the reset, we need to reload the CSB read/write pointers */
+ reset_csb_pointers(engine);
+
+ /*
+ * Save the currently executing context, even if we completed
+ * its request, it was still running at the time of the
+ * reset and will have been clobbered.
+ */
+ rq = active_context(engine, engine->execlists.reset_ccid);
+ if (!rq)
+ goto unwind;
+
+ ce = rq->context;
+ GEM_BUG_ON(!i915_vma_is_pinned(ce->state));
+
+ if (i915_request_completed(rq)) {
+ /* Idle context; tidy up the ring so we can restart afresh */
+ head = intel_ring_wrap(ce->ring, rq->tail);
+ goto out_replay;
+ }
+
+ /* We still have requests in-flight; the engine should be active */
+ GEM_BUG_ON(!intel_engine_pm_is_awake(engine));
+
+ /* Context has requests still in-flight; it should not be idle! */
+ GEM_BUG_ON(i915_active_is_idle(&ce->active));
+
+ rq = active_request(ce->timeline, rq);
+ head = intel_ring_wrap(ce->ring, rq->head);
+ GEM_BUG_ON(head == ce->ring->tail);
+
+ /*
+ * If this request hasn't started yet, e.g. it is waiting on a
+ * semaphore, we need to avoid skipping the request or else we
+ * break the signaling chain. However, if the context is corrupt
+ * the request will not restart and we will be stuck with a wedged
+ * device. It is quite often the case that if we issue a reset
+ * while the GPU is loading the context image, that the context
+ * image becomes corrupt.
+ *
+ * Otherwise, if we have not started yet, the request should replay
+ * perfectly and we do not need to flag the result as being erroneous.
+ */
+ if (!i915_request_started(rq))
+ goto out_replay;
+
+ /*
+ * If the request was innocent, we leave the request in the ELSP
+ * and will try to replay it on restarting. The context image may
+ * have been corrupted by the reset, in which case we may have
+ * to service a new GPU hang, but more likely we can continue on
+ * without impact.
+ *
+ * If the request was guilty, we presume the context is corrupt
+ * and have to at least restore the RING register in the context
+ * image back to the expected values to skip over the guilty request.
+ */
+ __i915_request_reset(rq, stalled);
+
+ /*
+ * We want a simple context + ring to execute the breadcrumb update.
+ * We cannot rely on the context being intact across the GPU hang,
+ * so clear it and rebuild just what we need for the breadcrumb.
+ * All pending requests for this context will be zapped, and any
+ * future request will be after userspace has had the opportunity
+ * to recreate its own state.
+ */
+out_replay:
+ ENGINE_TRACE(engine, "replay {head:%04x, tail:%04x}\n",
+ head, ce->ring->tail);
+ __execlists_reset_reg_state(ce, engine);
+ __execlists_update_reg_state(ce, engine, head);
+ ce->lrc.desc |= CTX_DESC_FORCE_RESTORE; /* paranoid: GPU was reset! */
+
+unwind:
+ /* Push back any incomplete requests for replay after the reset. */
+ cancel_port_requests(execlists);
+ __unwind_incomplete_requests(engine);
+}
+
+static void execlists_reset_rewind(struct intel_engine_cs *engine, bool stalled)
+{
+ unsigned long flags;
+
+ ENGINE_TRACE(engine, "\n");
+
+ spin_lock_irqsave(&engine->active.lock, flags);
+
+ __execlists_reset(engine, stalled);
+
+ spin_unlock_irqrestore(&engine->active.lock, flags);
+}
+
+static void nop_submission_tasklet(unsigned long data)
+{
+ struct intel_engine_cs * const engine = (struct intel_engine_cs *)data;
+
+ /* The driver is wedged; don't process any more events. */
+ WRITE_ONCE(engine->execlists.queue_priority_hint, INT_MIN);
+}
+
+static void execlists_reset_cancel(struct intel_engine_cs *engine)
+{
+ struct intel_engine_execlists * const execlists = &engine->execlists;
+ struct i915_request *rq, *rn;
+ struct rb_node *rb;
+ unsigned long flags;
+
+ ENGINE_TRACE(engine, "\n");
+
+ /*
+ * Before we call engine->cancel_requests(), we should have exclusive
+ * access to the submission state. This is arranged for us by the
+ * caller disabling the interrupt generation, the tasklet and other
+ * threads that may then access the same state, giving us a free hand
+ * to reset state. However, we still need to let lockdep be aware that
+ * we know this state may be accessed in hardirq context, so we
+ * disable the irq around this manipulation and we want to keep
+ * the spinlock focused on its duties and not accidentally conflate
+ * coverage to the submission's irq state. (Similarly, although we
+ * shouldn't need to disable irq around the manipulation of the
+ * submission's irq state, we also wish to remind ourselves that
+ * it is irq state.)
+ */
+ spin_lock_irqsave(&engine->active.lock, flags);
+
+ __execlists_reset(engine, true);
+
+ /* Mark all executing requests as skipped. */
+ list_for_each_entry(rq, &engine->active.requests, sched.link)
+ mark_eio(rq);
+ intel_engine_signal_breadcrumbs(engine);
+
+ /* Flush the queued requests to the timeline list (for retiring). */
+ while ((rb = rb_first_cached(&execlists->queue))) {
+ struct i915_priolist *p = to_priolist(rb);
+ int i;
+
+ priolist_for_each_request_consume(rq, rn, p, i) {
+ mark_eio(rq);
+ __i915_request_submit(rq);
+ }
+
+ rb_erase_cached(&p->node, &execlists->queue);
+ i915_priolist_free(p);
+ }
+
+ /* On-hold requests will be flushed to timeline upon their release */
+ list_for_each_entry(rq, &engine->active.hold, sched.link)
+ mark_eio(rq);
+
+ /* Cancel all attached virtual engines */
+ while ((rb = rb_first_cached(&execlists->virtual))) {
+ struct virtual_engine *ve =
+ rb_entry(rb, typeof(*ve), nodes[engine->id].rb);
+
+ rb_erase_cached(rb, &execlists->virtual);
+ RB_CLEAR_NODE(rb);
+
+ spin_lock(&ve->base.active.lock);
+ rq = fetch_and_zero(&ve->request);
+ if (rq) {
+ mark_eio(rq);
+
+ rq->engine = engine;
+ __i915_request_submit(rq);
+ i915_request_put(rq);
+
+ ve->base.execlists.queue_priority_hint = INT_MIN;
+ }
+ spin_unlock(&ve->base.active.lock);
+ }
+
+ /* Remaining _unready_ requests will be nop'ed when submitted */
+
+ execlists->queue_priority_hint = INT_MIN;
+ execlists->queue = RB_ROOT_CACHED;
+
+ GEM_BUG_ON(__tasklet_is_enabled(&execlists->tasklet));
+ execlists->tasklet.func = nop_submission_tasklet;
+
+ spin_unlock_irqrestore(&engine->active.lock, flags);
+}
+
+static void execlists_reset_finish(struct intel_engine_cs *engine)
+{
+ struct intel_engine_execlists * const execlists = &engine->execlists;
+
+ /*
+ * After a GPU reset, we may have requests to replay. Do so now while
+ * we still have the forcewake to be sure that the GPU is not allowed
+ * to sleep before we restart and reload a context.
+ */
+ GEM_BUG_ON(!reset_in_progress(execlists));
+ if (!RB_EMPTY_ROOT(&execlists->queue.rb_root))
+ execlists->tasklet.func(execlists->tasklet.data);
+
+ if (__tasklet_enable(&execlists->tasklet))
+ /* And kick in case we missed a new request submission. */
+ tasklet_hi_schedule(&execlists->tasklet);
+ ENGINE_TRACE(engine, "depth->%d\n",
+ atomic_read(&execlists->tasklet.count));
+}
+
+static int gen8_emit_bb_start_noarb(struct i915_request *rq,
+ u64 offset, u32 len,
+ const unsigned int flags)
+{
+ u32 *cs;
+
+ cs = intel_ring_begin(rq, 4);
+ if (IS_ERR(cs))
+ return PTR_ERR(cs);
+
+ /*
+ * WaDisableCtxRestoreArbitration:bdw,chv
+ *
+ * We don't need to perform MI_ARB_ENABLE as often as we do (in
+ * particular all the gen that do not need the w/a at all!), if we
+ * took care to make sure that on every switch into this context
+ * (both ordinary and for preemption) that arbitrartion was enabled
+ * we would be fine. However, for gen8 there is another w/a that
+ * requires us to not preempt inside GPGPU execution, so we keep
+ * arbitration disabled for gen8 batches. Arbitration will be
+ * re-enabled before we close the request
+ * (engine->emit_fini_breadcrumb).
+ */
+ *cs++ = MI_ARB_ON_OFF | MI_ARB_DISABLE;
+
+ /* FIXME(BDW+): Address space and security selectors. */
+ *cs++ = MI_BATCH_BUFFER_START_GEN8 |
+ (flags & I915_DISPATCH_SECURE ? 0 : BIT(8));
+ *cs++ = lower_32_bits(offset);
+ *cs++ = upper_32_bits(offset);
+
+ intel_ring_advance(rq, cs);
+
+ return 0;
+}
+
+static int gen8_emit_bb_start(struct i915_request *rq,
+ u64 offset, u32 len,
+ const unsigned int flags)
+{
+ u32 *cs;
+
+ cs = intel_ring_begin(rq, 6);
+ if (IS_ERR(cs))
+ return PTR_ERR(cs);
+
+ *cs++ = MI_ARB_ON_OFF | MI_ARB_ENABLE;
+
+ *cs++ = MI_BATCH_BUFFER_START_GEN8 |
+ (flags & I915_DISPATCH_SECURE ? 0 : BIT(8));
+ *cs++ = lower_32_bits(offset);
+ *cs++ = upper_32_bits(offset);
+
+ *cs++ = MI_ARB_ON_OFF | MI_ARB_DISABLE;
+ *cs++ = MI_NOOP;
+
+ intel_ring_advance(rq, cs);
+
+ return 0;
+}
+
+static void gen8_logical_ring_enable_irq(struct intel_engine_cs *engine)
+{
+ ENGINE_WRITE(engine, RING_IMR,
+ ~(engine->irq_enable_mask | engine->irq_keep_mask));
+ ENGINE_POSTING_READ(engine, RING_IMR);
+}
+
+static void gen8_logical_ring_disable_irq(struct intel_engine_cs *engine)
+{
+ ENGINE_WRITE(engine, RING_IMR, ~engine->irq_keep_mask);
+}
+
+static int gen8_emit_flush(struct i915_request *request, u32 mode)
+{
+ u32 cmd, *cs;
+
+ cs = intel_ring_begin(request, 4);
+ if (IS_ERR(cs))
+ return PTR_ERR(cs);
+
+ cmd = MI_FLUSH_DW + 1;
+
+ /* We always require a command barrier so that subsequent
+ * commands, such as breadcrumb interrupts, are strictly ordered
+ * wrt the contents of the write cache being flushed to memory
+ * (and thus being coherent from the CPU).
+ */
+ cmd |= MI_FLUSH_DW_STORE_INDEX | MI_FLUSH_DW_OP_STOREDW;
+
+ if (mode & EMIT_INVALIDATE) {
+ cmd |= MI_INVALIDATE_TLB;
+ if (request->engine->class == VIDEO_DECODE_CLASS)
+ cmd |= MI_INVALIDATE_BSD;
+ }
+
+ *cs++ = cmd;
+ *cs++ = LRC_PPHWSP_SCRATCH_ADDR;
+ *cs++ = 0; /* upper addr */
+ *cs++ = 0; /* value */
+ intel_ring_advance(request, cs);
+
+ return 0;
+}
+
+static int gen8_emit_flush_render(struct i915_request *request,
+ u32 mode)
+{
+ bool vf_flush_wa = false, dc_flush_wa = false;
+ u32 *cs, flags = 0;
+ int len;
+
+ flags |= PIPE_CONTROL_CS_STALL;
+
+ if (mode & EMIT_FLUSH) {
+ flags |= PIPE_CONTROL_RENDER_TARGET_CACHE_FLUSH;
+ flags |= PIPE_CONTROL_DEPTH_CACHE_FLUSH;
+ flags |= PIPE_CONTROL_DC_FLUSH_ENABLE;
+ flags |= PIPE_CONTROL_FLUSH_ENABLE;
+ }
+
+ if (mode & EMIT_INVALIDATE) {
+ flags |= PIPE_CONTROL_TLB_INVALIDATE;
+ flags |= PIPE_CONTROL_INSTRUCTION_CACHE_INVALIDATE;
+ flags |= PIPE_CONTROL_TEXTURE_CACHE_INVALIDATE;
+ flags |= PIPE_CONTROL_VF_CACHE_INVALIDATE;
+ flags |= PIPE_CONTROL_CONST_CACHE_INVALIDATE;
+ flags |= PIPE_CONTROL_STATE_CACHE_INVALIDATE;
+ flags |= PIPE_CONTROL_QW_WRITE;
+ flags |= PIPE_CONTROL_STORE_DATA_INDEX;
+
+ /*
+ * On GEN9: before VF_CACHE_INVALIDATE we need to emit a NULL
+ * pipe control.
+ */
+ if (IS_GEN(request->engine->i915, 9))
+ vf_flush_wa = true;
+
+ /* WaForGAMHang:kbl */
+ if (IS_KBL_GT_REVID(request->engine->i915, 0, KBL_REVID_B0))
+ dc_flush_wa = true;
+ }
+
+ len = 6;
+
+ if (vf_flush_wa)
+ len += 6;
+
+ if (dc_flush_wa)
+ len += 12;
+
+ cs = intel_ring_begin(request, len);
+ if (IS_ERR(cs))
+ return PTR_ERR(cs);
+
+ if (vf_flush_wa)
+ cs = gen8_emit_pipe_control(cs, 0, 0);
+
+ if (dc_flush_wa)
+ cs = gen8_emit_pipe_control(cs, PIPE_CONTROL_DC_FLUSH_ENABLE,
+ 0);
+
+ cs = gen8_emit_pipe_control(cs, flags, LRC_PPHWSP_SCRATCH_ADDR);
+
+ if (dc_flush_wa)
+ cs = gen8_emit_pipe_control(cs, PIPE_CONTROL_CS_STALL, 0);
+
+ intel_ring_advance(request, cs);
+
+ return 0;
+}
+
+static int gen11_emit_flush_render(struct i915_request *request,
+ u32 mode)
+{
+ if (mode & EMIT_FLUSH) {
+ u32 *cs;
+ u32 flags = 0;
+
+ flags |= PIPE_CONTROL_CS_STALL;
+
+ flags |= PIPE_CONTROL_TILE_CACHE_FLUSH;
+ flags |= PIPE_CONTROL_RENDER_TARGET_CACHE_FLUSH;
+ flags |= PIPE_CONTROL_DEPTH_CACHE_FLUSH;
+ flags |= PIPE_CONTROL_DC_FLUSH_ENABLE;
+ flags |= PIPE_CONTROL_FLUSH_ENABLE;
+ flags |= PIPE_CONTROL_QW_WRITE;
+ flags |= PIPE_CONTROL_STORE_DATA_INDEX;
+
+ cs = intel_ring_begin(request, 6);
+ if (IS_ERR(cs))
+ return PTR_ERR(cs);
+
+ cs = gen8_emit_pipe_control(cs, flags, LRC_PPHWSP_SCRATCH_ADDR);
+ intel_ring_advance(request, cs);
+ }
+
+ if (mode & EMIT_INVALIDATE) {
+ u32 *cs;
+ u32 flags = 0;
+
+ flags |= PIPE_CONTROL_CS_STALL;
+
+ flags |= PIPE_CONTROL_COMMAND_CACHE_INVALIDATE;
+ flags |= PIPE_CONTROL_TLB_INVALIDATE;
+ flags |= PIPE_CONTROL_INSTRUCTION_CACHE_INVALIDATE;
+ flags |= PIPE_CONTROL_TEXTURE_CACHE_INVALIDATE;
+ flags |= PIPE_CONTROL_VF_CACHE_INVALIDATE;
+ flags |= PIPE_CONTROL_CONST_CACHE_INVALIDATE;
+ flags |= PIPE_CONTROL_STATE_CACHE_INVALIDATE;
+ flags |= PIPE_CONTROL_QW_WRITE;
+ flags |= PIPE_CONTROL_STORE_DATA_INDEX;
+
+ cs = intel_ring_begin(request, 6);
+ if (IS_ERR(cs))
+ return PTR_ERR(cs);
+
+ cs = gen8_emit_pipe_control(cs, flags, LRC_PPHWSP_SCRATCH_ADDR);
+ intel_ring_advance(request, cs);
+ }
+
+ return 0;
+}
+
+static u32 preparser_disable(bool state)
+{
+ return MI_ARB_CHECK | 1 << 8 | state;
+}
+
+static i915_reg_t aux_inv_reg(const struct intel_engine_cs *engine)
+{
+ static const i915_reg_t vd[] = {
+ GEN12_VD0_AUX_NV,
+ GEN12_VD1_AUX_NV,
+ GEN12_VD2_AUX_NV,
+ GEN12_VD3_AUX_NV,
+ };
+
+ static const i915_reg_t ve[] = {
+ GEN12_VE0_AUX_NV,
+ GEN12_VE1_AUX_NV,
+ };
+
+ if (engine->class == VIDEO_DECODE_CLASS)
+ return vd[engine->instance];
+
+ if (engine->class == VIDEO_ENHANCEMENT_CLASS)
+ return ve[engine->instance];
+
+ GEM_BUG_ON("unknown aux_inv_reg\n");
+
+ return INVALID_MMIO_REG;
+}
+
+static u32 *
+gen12_emit_aux_table_inv(const i915_reg_t inv_reg, u32 *cs)
+{
+ *cs++ = MI_LOAD_REGISTER_IMM(1);
+ *cs++ = i915_mmio_reg_offset(inv_reg);
+ *cs++ = AUX_INV;
+ *cs++ = MI_NOOP;
+
+ return cs;
+}
+
+static int gen12_emit_flush_render(struct i915_request *request,
+ u32 mode)
+{
+ if (mode & EMIT_FLUSH) {
+ u32 flags = 0;
+ u32 *cs;
+
+ flags |= PIPE_CONTROL_TILE_CACHE_FLUSH;
+ flags |= PIPE_CONTROL_FLUSH_L3;
+ flags |= PIPE_CONTROL_RENDER_TARGET_CACHE_FLUSH;
+ flags |= PIPE_CONTROL_DEPTH_CACHE_FLUSH;
+ /* Wa_1409600907:tgl */
+ flags |= PIPE_CONTROL_DEPTH_STALL;
+ flags |= PIPE_CONTROL_DC_FLUSH_ENABLE;
+ flags |= PIPE_CONTROL_FLUSH_ENABLE;
+
+ flags |= PIPE_CONTROL_STORE_DATA_INDEX;
+ flags |= PIPE_CONTROL_QW_WRITE;
+
+ flags |= PIPE_CONTROL_CS_STALL;
+
+ cs = intel_ring_begin(request, 6);
+ if (IS_ERR(cs))
+ return PTR_ERR(cs);
+
+ cs = gen12_emit_pipe_control(cs,
+ PIPE_CONTROL0_HDC_PIPELINE_FLUSH,
+ flags, LRC_PPHWSP_SCRATCH_ADDR);
+ intel_ring_advance(request, cs);
+ }
+
+ if (mode & EMIT_INVALIDATE) {
+ u32 flags = 0;
+ u32 *cs;
+
+ flags |= PIPE_CONTROL_COMMAND_CACHE_INVALIDATE;
+ flags |= PIPE_CONTROL_TLB_INVALIDATE;
+ flags |= PIPE_CONTROL_INSTRUCTION_CACHE_INVALIDATE;
+ flags |= PIPE_CONTROL_TEXTURE_CACHE_INVALIDATE;
+ flags |= PIPE_CONTROL_VF_CACHE_INVALIDATE;
+ flags |= PIPE_CONTROL_CONST_CACHE_INVALIDATE;
+ flags |= PIPE_CONTROL_STATE_CACHE_INVALIDATE;
+
+ flags |= PIPE_CONTROL_STORE_DATA_INDEX;
+ flags |= PIPE_CONTROL_QW_WRITE;
+
+ flags |= PIPE_CONTROL_CS_STALL;
+
+ cs = intel_ring_begin(request, 8 + 4);
+ if (IS_ERR(cs))
+ return PTR_ERR(cs);
+
+ /*
+ * Prevent the pre-parser from skipping past the TLB
+ * invalidate and loading a stale page for the batch
+ * buffer / request payload.
+ */
+ *cs++ = preparser_disable(true);
+
+ cs = gen8_emit_pipe_control(cs, flags, LRC_PPHWSP_SCRATCH_ADDR);
+
+ /* hsdes: 1809175790 */
+ cs = gen12_emit_aux_table_inv(GEN12_GFX_CCS_AUX_NV, cs);
+
+ *cs++ = preparser_disable(false);
+ intel_ring_advance(request, cs);
+ }
+
+ return 0;
+}
+
+static int gen12_emit_flush(struct i915_request *request, u32 mode)
+{
+ intel_engine_mask_t aux_inv = 0;
+ u32 cmd, *cs;
+
+ cmd = 4;
+ if (mode & EMIT_INVALIDATE)
+ cmd += 2;
+ if (mode & EMIT_INVALIDATE)
+ aux_inv = request->engine->mask & ~BIT(BCS0);
+ if (aux_inv)
+ cmd += 2 * hweight8(aux_inv) + 2;
+
+ cs = intel_ring_begin(request, cmd);
+ if (IS_ERR(cs))
+ return PTR_ERR(cs);
+
+ if (mode & EMIT_INVALIDATE)
+ *cs++ = preparser_disable(true);
+
+ cmd = MI_FLUSH_DW + 1;
+
+ /* We always require a command barrier so that subsequent
+ * commands, such as breadcrumb interrupts, are strictly ordered
+ * wrt the contents of the write cache being flushed to memory
+ * (and thus being coherent from the CPU).
+ */
+ cmd |= MI_FLUSH_DW_STORE_INDEX | MI_FLUSH_DW_OP_STOREDW;
+
+ if (mode & EMIT_INVALIDATE) {
+ cmd |= MI_INVALIDATE_TLB;
+ if (request->engine->class == VIDEO_DECODE_CLASS)
+ cmd |= MI_INVALIDATE_BSD;
+ }
+
+ *cs++ = cmd;
+ *cs++ = LRC_PPHWSP_SCRATCH_ADDR;
+ *cs++ = 0; /* upper addr */
+ *cs++ = 0; /* value */
+
+ if (aux_inv) { /* hsdes: 1809175790 */
+ struct intel_engine_cs *engine;
+ unsigned int tmp;
+
+ *cs++ = MI_LOAD_REGISTER_IMM(hweight8(aux_inv));
+ for_each_engine_masked(engine, request->engine->gt,
+ aux_inv, tmp) {
+ *cs++ = i915_mmio_reg_offset(aux_inv_reg(engine));
+ *cs++ = AUX_INV;
+ }
+ *cs++ = MI_NOOP;
+ }
+
+ if (mode & EMIT_INVALIDATE)
+ *cs++ = preparser_disable(false);
+
+ intel_ring_advance(request, cs);
+
+ return 0;
+}
+
+static void assert_request_valid(struct i915_request *rq)
+{
+ struct intel_ring *ring __maybe_unused = rq->ring;
+
+ /* Can we unwind this request without appearing to go forwards? */
+ GEM_BUG_ON(intel_ring_direction(ring, rq->wa_tail, rq->head) <= 0);
+}
+
+/*
+ * Reserve space for 2 NOOPs at the end of each request to be
+ * used as a workaround for not being allowed to do lite
+ * restore with HEAD==TAIL (WaIdleLiteRestore).
+ */
+static u32 *gen8_emit_wa_tail(struct i915_request *request, u32 *cs)
+{
+ /* Ensure there's always at least one preemption point per-request. */
+ *cs++ = MI_ARB_CHECK;
+ *cs++ = MI_NOOP;
+ request->wa_tail = intel_ring_offset(request, cs);
+
+ /* Check that entire request is less than half the ring */
+ assert_request_valid(request);
+
+ return cs;
+}
+
+static u32 *emit_preempt_busywait(struct i915_request *request, u32 *cs)
+{
+ *cs++ = MI_SEMAPHORE_WAIT |
+ MI_SEMAPHORE_GLOBAL_GTT |
+ MI_SEMAPHORE_POLL |
+ MI_SEMAPHORE_SAD_EQ_SDD;
+ *cs++ = 0;
+ *cs++ = intel_hws_preempt_address(request->engine);
+ *cs++ = 0;
+
+ return cs;
+}
+
+static __always_inline u32*
+gen8_emit_fini_breadcrumb_tail(struct i915_request *request, u32 *cs)
+{
+ *cs++ = MI_USER_INTERRUPT;
+
+ *cs++ = MI_ARB_ON_OFF | MI_ARB_ENABLE;
+ if (intel_engine_has_semaphores(request->engine))
+ cs = emit_preempt_busywait(request, cs);
+
+ request->tail = intel_ring_offset(request, cs);
+ assert_ring_tail_valid(request->ring, request->tail);
+
+ return gen8_emit_wa_tail(request, cs);
+}
+
+static u32 *emit_xcs_breadcrumb(struct i915_request *rq, u32 *cs)
+{
+ return gen8_emit_ggtt_write(cs, rq->fence.seqno, hwsp_offset(rq), 0);
+}
+
+static u32 *gen8_emit_fini_breadcrumb(struct i915_request *rq, u32 *cs)
+{
+ return gen8_emit_fini_breadcrumb_tail(rq, emit_xcs_breadcrumb(rq, cs));
+}
+
+static u32 *gen8_emit_fini_breadcrumb_rcs(struct i915_request *request, u32 *cs)
+{
+ cs = gen8_emit_pipe_control(cs,
+ PIPE_CONTROL_RENDER_TARGET_CACHE_FLUSH |
+ PIPE_CONTROL_DEPTH_CACHE_FLUSH |
+ PIPE_CONTROL_DC_FLUSH_ENABLE,
+ 0);
+
+ /* XXX flush+write+CS_STALL all in one upsets gem_concurrent_blt:kbl */
+ cs = gen8_emit_ggtt_write_rcs(cs,
+ request->fence.seqno,
+ hwsp_offset(request),
+ PIPE_CONTROL_FLUSH_ENABLE |
+ PIPE_CONTROL_CS_STALL);
+
+ return gen8_emit_fini_breadcrumb_tail(request, cs);
+}
+
+static u32 *
+gen11_emit_fini_breadcrumb_rcs(struct i915_request *request, u32 *cs)
+{
+ cs = gen8_emit_ggtt_write_rcs(cs,
+ request->fence.seqno,
+ hwsp_offset(request),
+ PIPE_CONTROL_CS_STALL |
+ PIPE_CONTROL_TILE_CACHE_FLUSH |
+ PIPE_CONTROL_RENDER_TARGET_CACHE_FLUSH |
+ PIPE_CONTROL_DEPTH_CACHE_FLUSH |
+ PIPE_CONTROL_DC_FLUSH_ENABLE |
+ PIPE_CONTROL_FLUSH_ENABLE);
+
+ return gen8_emit_fini_breadcrumb_tail(request, cs);
+}
+
+/*
+ * Note that the CS instruction pre-parser will not stall on the breadcrumb
+ * flush and will continue pre-fetching the instructions after it before the
+ * memory sync is completed. On pre-gen12 HW, the pre-parser will stop at
+ * BB_START/END instructions, so, even though we might pre-fetch the pre-amble
+ * of the next request before the memory has been flushed, we're guaranteed that
+ * we won't access the batch itself too early.
+ * However, on gen12+ the parser can pre-fetch across the BB_START/END commands,
+ * so, if the current request is modifying an instruction in the next request on
+ * the same intel_context, we might pre-fetch and then execute the pre-update
+ * instruction. To avoid this, the users of self-modifying code should either
+ * disable the parser around the code emitting the memory writes, via a new flag
+ * added to MI_ARB_CHECK, or emit the writes from a different intel_context. For
+ * the in-kernel use-cases we've opted to use a separate context, see
+ * reloc_gpu() as an example.
+ * All the above applies only to the instructions themselves. Non-inline data
+ * used by the instructions is not pre-fetched.
+ */
+
+static u32 *gen12_emit_preempt_busywait(struct i915_request *request, u32 *cs)
+{
+ *cs++ = MI_SEMAPHORE_WAIT_TOKEN |
+ MI_SEMAPHORE_GLOBAL_GTT |
+ MI_SEMAPHORE_POLL |
+ MI_SEMAPHORE_SAD_EQ_SDD;
+ *cs++ = 0;
+ *cs++ = intel_hws_preempt_address(request->engine);
+ *cs++ = 0;
+ *cs++ = 0;
+ *cs++ = MI_NOOP;
+
+ return cs;
+}
+
+static __always_inline u32*
+gen12_emit_fini_breadcrumb_tail(struct i915_request *request, u32 *cs)
+{
+ *cs++ = MI_USER_INTERRUPT;
+
+ *cs++ = MI_ARB_ON_OFF | MI_ARB_ENABLE;
+ if (intel_engine_has_semaphores(request->engine))
+ cs = gen12_emit_preempt_busywait(request, cs);
+
+ request->tail = intel_ring_offset(request, cs);
+ assert_ring_tail_valid(request->ring, request->tail);
+
+ return gen8_emit_wa_tail(request, cs);
+}
+
+static u32 *gen12_emit_fini_breadcrumb(struct i915_request *rq, u32 *cs)
+{
+ /* XXX Stalling flush before seqno write; post-sync not */
+ cs = emit_xcs_breadcrumb(rq, __gen8_emit_flush_dw(cs, 0, 0, 0));
+ return gen12_emit_fini_breadcrumb_tail(rq, cs);
+}
+
+static u32 *
+gen12_emit_fini_breadcrumb_rcs(struct i915_request *request, u32 *cs)
+{
+ cs = gen12_emit_ggtt_write_rcs(cs,
+ request->fence.seqno,
+ hwsp_offset(request),
+ PIPE_CONTROL0_HDC_PIPELINE_FLUSH,
+ PIPE_CONTROL_CS_STALL |
+ PIPE_CONTROL_TILE_CACHE_FLUSH |
+ PIPE_CONTROL_FLUSH_L3 |
+ PIPE_CONTROL_RENDER_TARGET_CACHE_FLUSH |
+ PIPE_CONTROL_DEPTH_CACHE_FLUSH |
+ /* Wa_1409600907:tgl */
+ PIPE_CONTROL_DEPTH_STALL |
+ PIPE_CONTROL_DC_FLUSH_ENABLE |
+ PIPE_CONTROL_FLUSH_ENABLE);
+
+ return gen12_emit_fini_breadcrumb_tail(request, cs);
+}
+
+static void execlists_park(struct intel_engine_cs *engine)
+{
+ cancel_timer(&engine->execlists.timer);
+ cancel_timer(&engine->execlists.preempt);
+}
+
+void intel_execlists_set_default_submission(struct intel_engine_cs *engine)
+{
+ engine->submit_request = execlists_submit_request;
+ engine->schedule = i915_schedule;
+ engine->execlists.tasklet.func = execlists_submission_tasklet;
+
+ engine->reset.prepare = execlists_reset_prepare;
+ engine->reset.rewind = execlists_reset_rewind;
+ engine->reset.cancel = execlists_reset_cancel;
+ engine->reset.finish = execlists_reset_finish;
+
+ engine->park = execlists_park;
+ engine->unpark = NULL;
+
+ engine->flags |= I915_ENGINE_SUPPORTS_STATS;
+ if (!intel_vgpu_active(engine->i915)) {
+ engine->flags |= I915_ENGINE_HAS_SEMAPHORES;
+ if (HAS_LOGICAL_RING_PREEMPTION(engine->i915)) {
+ engine->flags |= I915_ENGINE_HAS_PREEMPTION;
+ if (IS_ACTIVE(CONFIG_DRM_I915_TIMESLICE_DURATION))
+ engine->flags |= I915_ENGINE_HAS_TIMESLICES;
+ }
+ }
+
+ if (INTEL_GEN(engine->i915) >= 12)
+ engine->flags |= I915_ENGINE_HAS_RELATIVE_MMIO;
+
+ if (intel_engine_has_preemption(engine))
+ engine->emit_bb_start = gen8_emit_bb_start;
+ else
+ engine->emit_bb_start = gen8_emit_bb_start_noarb;
+}
+
+static void execlists_shutdown(struct intel_engine_cs *engine)
+{
+ /* Synchronise with residual timers and any softirq they raise */
+ del_timer_sync(&engine->execlists.timer);
+ del_timer_sync(&engine->execlists.preempt);
+ tasklet_kill(&engine->execlists.tasklet);
+}
+
+static void execlists_release(struct intel_engine_cs *engine)
+{
+ engine->sanitize = NULL; /* no longer in control, nothing to sanitize */
+
+ execlists_shutdown(engine);
+
+ intel_engine_cleanup_common(engine);
+ lrc_destroy_wa_ctx(engine);
+}
+
+static void
+logical_ring_default_vfuncs(struct intel_engine_cs *engine)
+{
+ /* Default vfuncs which can be overriden by each engine. */
+
+ engine->resume = execlists_resume;
+
+ engine->cops = &execlists_context_ops;
+ engine->request_alloc = execlists_request_alloc;
+
+ engine->emit_flush = gen8_emit_flush;
+ engine->emit_init_breadcrumb = gen8_emit_init_breadcrumb;
+ engine->emit_fini_breadcrumb = gen8_emit_fini_breadcrumb;
+ if (INTEL_GEN(engine->i915) >= 12) {
+ engine->emit_fini_breadcrumb = gen12_emit_fini_breadcrumb;
+ engine->emit_flush = gen12_emit_flush;
+ }
+ engine->set_default_submission = intel_execlists_set_default_submission;
+
+ if (INTEL_GEN(engine->i915) < 11) {
+ engine->irq_enable = gen8_logical_ring_enable_irq;
+ engine->irq_disable = gen8_logical_ring_disable_irq;
+ } else {
+ /*
+ * TODO: On Gen11 interrupt masks need to be clear
+ * to allow C6 entry. Keep interrupts enabled at
+ * and take the hit of generating extra interrupts
+ * until a more refined solution exists.
+ */
+ }
+}
+
+static inline void
+logical_ring_default_irqs(struct intel_engine_cs *engine)
+{
+ unsigned int shift = 0;
+
+ if (INTEL_GEN(engine->i915) < 11) {
+ const u8 irq_shifts[] = {
+ [RCS0] = GEN8_RCS_IRQ_SHIFT,
+ [BCS0] = GEN8_BCS_IRQ_SHIFT,
+ [VCS0] = GEN8_VCS0_IRQ_SHIFT,
+ [VCS1] = GEN8_VCS1_IRQ_SHIFT,
+ [VECS0] = GEN8_VECS_IRQ_SHIFT,
+ };
+
+ shift = irq_shifts[engine->id];
+ }
+
+ engine->irq_enable_mask = GT_RENDER_USER_INTERRUPT << shift;
+ engine->irq_keep_mask = GT_CONTEXT_SWITCH_INTERRUPT << shift;
+ engine->irq_keep_mask |= GT_CS_MASTER_ERROR_INTERRUPT << shift;
+ engine->irq_keep_mask |= GT_WAIT_SEMAPHORE_INTERRUPT << shift;
+}
+
+static void rcs_submission_override(struct intel_engine_cs *engine)
+{
+ switch (INTEL_GEN(engine->i915)) {
+ case 12:
+ engine->emit_flush = gen12_emit_flush_render;
+ engine->emit_fini_breadcrumb = gen12_emit_fini_breadcrumb_rcs;
+ break;
+ case 11:
+ engine->emit_flush = gen11_emit_flush_render;
+ engine->emit_fini_breadcrumb = gen11_emit_fini_breadcrumb_rcs;
+ break;
+ default:
+ engine->emit_flush = gen8_emit_flush_render;
+ engine->emit_fini_breadcrumb = gen8_emit_fini_breadcrumb_rcs;
+ break;
+ }
+}
+
+int intel_execlists_submission_setup(struct intel_engine_cs *engine)
+{
+ struct intel_engine_execlists * const execlists = &engine->execlists;
+ struct drm_i915_private *i915 = engine->i915;
+ struct intel_uncore *uncore = engine->uncore;
+ u32 base = engine->mmio_base;
+
+ tasklet_init(&engine->execlists.tasklet,
+ execlists_submission_tasklet, (unsigned long)engine);
+ timer_setup(&engine->execlists.timer, execlists_timeslice, 0);
+ timer_setup(&engine->execlists.preempt, execlists_preempt, 0);
+
+ logical_ring_default_vfuncs(engine);
+ logical_ring_default_irqs(engine);
+
+ if (engine->class == RENDER_CLASS)
+ rcs_submission_override(engine);
+
+ if (intel_init_workaround_bb(engine))
+ /*
+ * We continue even if we fail to initialize WA batch
+ * because we only expect rare glitches but nothing
+ * critical to prevent us from using GPU
+ */
+ drm_err(&i915->drm, "WA batch buffer initialization failed\n");
+
+ if (HAS_LOGICAL_RING_ELSQ(i915)) {
+ execlists->submit_reg = uncore->regs +
+ i915_mmio_reg_offset(RING_EXECLIST_SQ_CONTENTS(base));
+ execlists->ctrl_reg = uncore->regs +
+ i915_mmio_reg_offset(RING_EXECLIST_CONTROL(base));
+ } else {
+ execlists->submit_reg = uncore->regs +
+ i915_mmio_reg_offset(RING_ELSP(base));
+ }
+
+ execlists->csb_status =
+ (u64 *)&engine->status_page.addr[I915_HWS_CSB_BUF0_INDEX];
+
+ execlists->csb_write =
+ &engine->status_page.addr[intel_hws_csb_write_index(i915)];
+
+ if (INTEL_GEN(i915) < 11)
+ execlists->csb_size = GEN8_CSB_ENTRIES;
+ else
+ execlists->csb_size = GEN11_CSB_ENTRIES;
+
+ if (INTEL_GEN(engine->i915) >= 11) {
+ execlists->ccid |= engine->instance << (GEN11_ENGINE_INSTANCE_SHIFT - 32);
+ execlists->ccid |= engine->class << (GEN11_ENGINE_CLASS_SHIFT - 32);
+ }
+
+ /* Finally, take ownership and responsibility for cleanup! */
+ engine->sanitize = execlists_sanitize;
+ engine->release = execlists_release;
+
+ return 0;
+}
+
+static void init_common_reg_state(u32 * const regs,
+ const struct intel_engine_cs *engine,
+ const struct intel_ring *ring,
+ bool inhibit)
+{
+ u32 ctl;
+
+ ctl = _MASKED_BIT_ENABLE(CTX_CTRL_INHIBIT_SYN_CTX_SWITCH);
+ ctl |= _MASKED_BIT_DISABLE(CTX_CTRL_ENGINE_CTX_RESTORE_INHIBIT);
+ if (inhibit)
+ ctl |= CTX_CTRL_ENGINE_CTX_RESTORE_INHIBIT;
+ if (INTEL_GEN(engine->i915) < 11)
+ ctl |= _MASKED_BIT_DISABLE(CTX_CTRL_ENGINE_CTX_SAVE_INHIBIT |
+ CTX_CTRL_RS_CTX_ENABLE);
+ regs[CTX_CONTEXT_CONTROL] = ctl;
+
+ regs[CTX_RING_CTL] = RING_CTL_SIZE(ring->size) | RING_VALID;
+ regs[CTX_TIMESTAMP] = 0;
+}
+
+static void init_wa_bb_reg_state(u32 * const regs,
+ const struct intel_engine_cs *engine)
+{
+ const struct i915_ctx_workarounds * const wa_ctx = &engine->wa_ctx;
+
+ if (wa_ctx->per_ctx.size) {
+ const u32 ggtt_offset = i915_ggtt_offset(wa_ctx->vma);
+
+ GEM_BUG_ON(lrc_ring_wa_bb_per_ctx(engine) == -1);
+ regs[lrc_ring_wa_bb_per_ctx(engine) + 1] =
+ (ggtt_offset + wa_ctx->per_ctx.offset) | 0x01;
+ }
+
+ if (wa_ctx->indirect_ctx.size) {
+ lrc_ring_setup_indirect_ctx(regs, engine,
+ i915_ggtt_offset(wa_ctx->vma) +
+ wa_ctx->indirect_ctx.offset,
+ wa_ctx->indirect_ctx.size);
+ }
+}
+
+static void init_ppgtt_reg_state(u32 *regs, const struct i915_ppgtt *ppgtt)
+{
+ if (i915_vm_is_4lvl(&ppgtt->vm)) {
+ /* 64b PPGTT (48bit canonical)
+ * PDP0_DESCRIPTOR contains the base address to PML4 and
+ * other PDP Descriptors are ignored.
+ */
+ ASSIGN_CTX_PML4(ppgtt, regs);
+ } else {
+ ASSIGN_CTX_PDP(ppgtt, regs, 3);
+ ASSIGN_CTX_PDP(ppgtt, regs, 2);
+ ASSIGN_CTX_PDP(ppgtt, regs, 1);
+ ASSIGN_CTX_PDP(ppgtt, regs, 0);
+ }
+}
+
+static struct i915_ppgtt *vm_alias(struct i915_address_space *vm)
+{
+ if (i915_is_ggtt(vm))
+ return i915_vm_to_ggtt(vm)->alias;
+ else
+ return i915_vm_to_ppgtt(vm);
+}
+
+static void execlists_init_reg_state(u32 *regs,
+ const struct intel_context *ce,
+ const struct intel_engine_cs *engine,
+ const struct intel_ring *ring,
+ bool inhibit)
+{
+ /*
+ * A context is actually a big batch buffer with several
+ * MI_LOAD_REGISTER_IMM commands followed by (reg, value) pairs. The
+ * values we are setting here are only for the first context restore:
+ * on a subsequent save, the GPU will recreate this batchbuffer with new
+ * values (including all the missing MI_LOAD_REGISTER_IMM commands that
+ * we are not initializing here).
+ *
+ * Must keep consistent with virtual_update_register_offsets().
+ */
+ set_offsets(regs, reg_offsets(engine), engine, inhibit);
+
+ init_common_reg_state(regs, engine, ring, inhibit);
+ init_ppgtt_reg_state(regs, vm_alias(ce->vm));
+
+ init_wa_bb_reg_state(regs, engine);
+
+ __reset_stop_ring(regs, engine);
+}
+
+static int
+populate_lr_context(struct intel_context *ce,
+ struct drm_i915_gem_object *ctx_obj,
+ struct intel_engine_cs *engine,
+ struct intel_ring *ring)
+{
+ bool inhibit = true;
+ void *vaddr;
+
+ vaddr = i915_gem_object_pin_map(ctx_obj, I915_MAP_WB);
+ if (IS_ERR(vaddr)) {
+ drm_dbg(&engine->i915->drm, "Could not map object pages!\n");
+ return PTR_ERR(vaddr);
+ }
+
+ set_redzone(vaddr, engine);
+
+ if (engine->default_state) {
+ shmem_read(engine->default_state, 0,
+ vaddr, engine->context_size);
+ __set_bit(CONTEXT_VALID_BIT, &ce->flags);
+ inhibit = false;
+ }
+
+ /* Clear the ppHWSP (inc. per-context counters) */
+ memset(vaddr, 0, PAGE_SIZE);
+
+ /*
+ * The second page of the context object contains some registers which
+ * must be set up prior to the first execution.
+ */
+ execlists_init_reg_state(vaddr + LRC_STATE_OFFSET,
+ ce, engine, ring, inhibit);
+
+ __i915_gem_object_flush_map(ctx_obj, 0, engine->context_size);
+ i915_gem_object_unpin_map(ctx_obj);
+ return 0;
+}
+
+static struct intel_timeline *pinned_timeline(struct intel_context *ce)
+{
+ struct intel_timeline *tl = fetch_and_zero(&ce->timeline);
+
+ return intel_timeline_create_from_engine(ce->engine,
+ page_unmask_bits(tl));
+}
+
+static int __execlists_context_alloc(struct intel_context *ce,
+ struct intel_engine_cs *engine)
+{
+ struct drm_i915_gem_object *ctx_obj;
+ struct intel_ring *ring;
+ struct i915_vma *vma;
+ u32 context_size;
+ int ret;
+
+ GEM_BUG_ON(ce->state);
+ context_size = round_up(engine->context_size, I915_GTT_PAGE_SIZE);
+
+ if (IS_ENABLED(CONFIG_DRM_I915_DEBUG_GEM))
+ context_size += I915_GTT_PAGE_SIZE; /* for redzone */
+
+ if (INTEL_GEN(engine->i915) == 12) {
+ ce->wa_bb_page = context_size / PAGE_SIZE;
+ context_size += PAGE_SIZE;
+ }
+
+ ctx_obj = i915_gem_object_create_shmem(engine->i915, context_size);
+ if (IS_ERR(ctx_obj))
+ return PTR_ERR(ctx_obj);
+
+ vma = i915_vma_instance(ctx_obj, &engine->gt->ggtt->vm, NULL);
+ if (IS_ERR(vma)) {
+ ret = PTR_ERR(vma);
+ goto error_deref_obj;
+ }
+
+ if (!page_mask_bits(ce->timeline)) {
+ struct intel_timeline *tl;
+
+ /*
+ * Use the static global HWSP for the kernel context, and
+ * a dynamically allocated cacheline for everyone else.
+ */
+ if (unlikely(ce->timeline))
+ tl = pinned_timeline(ce);
+ else
+ tl = intel_timeline_create(engine->gt);
+ if (IS_ERR(tl)) {
+ ret = PTR_ERR(tl);
+ goto error_deref_obj;
+ }
+
+ ce->timeline = tl;
+ }
+
+ ring = intel_engine_create_ring(engine, (unsigned long)ce->ring);
+ if (IS_ERR(ring)) {
+ ret = PTR_ERR(ring);
+ goto error_deref_obj;
+ }
+
+ ret = populate_lr_context(ce, ctx_obj, engine, ring);
+ if (ret) {
+ drm_dbg(&engine->i915->drm,
+ "Failed to populate LRC: %d\n", ret);
+ goto error_ring_free;
+ }
+
+ ce->ring = ring;
+ ce->state = vma;
+
+ return 0;
+
+error_ring_free:
+ intel_ring_put(ring);
+error_deref_obj:
+ i915_gem_object_put(ctx_obj);
+ return ret;
+}
+
+static struct list_head *virtual_queue(struct virtual_engine *ve)
+{
+ return &ve->base.execlists.default_priolist.requests[0];
+}
+
+static void rcu_virtual_context_destroy(struct work_struct *wrk)
+{
+ struct virtual_engine *ve =
+ container_of(wrk, typeof(*ve), rcu.work);
+ unsigned int n;
+
+ GEM_BUG_ON(ve->context.inflight);
+
+ /* Preempt-to-busy may leave a stale request behind. */
+ if (unlikely(ve->request)) {
+ struct i915_request *old;
+
+ spin_lock_irq(&ve->base.active.lock);
+
+ old = fetch_and_zero(&ve->request);
+ if (old) {
+ GEM_BUG_ON(!i915_request_completed(old));
+ __i915_request_submit(old);
+ i915_request_put(old);
+ }
+
+ spin_unlock_irq(&ve->base.active.lock);
+ }
+
+ /*
+ * Flush the tasklet in case it is still running on another core.
+ *
+ * This needs to be done before we remove ourselves from the siblings'
+ * rbtrees as in the case it is running in parallel, it may reinsert
+ * the rb_node into a sibling.
+ */
+ tasklet_kill(&ve->base.execlists.tasklet);
+
+ /* Decouple ourselves from the siblings, no more access allowed. */
+ for (n = 0; n < ve->num_siblings; n++) {
+ struct intel_engine_cs *sibling = ve->siblings[n];
+ struct rb_node *node = &ve->nodes[sibling->id].rb;
+
+ if (RB_EMPTY_NODE(node))
+ continue;
+
+ spin_lock_irq(&sibling->active.lock);
+
+ /* Detachment is lazily performed in the execlists tasklet */
+ if (!RB_EMPTY_NODE(node))
+ rb_erase_cached(node, &sibling->execlists.virtual);
+
+ spin_unlock_irq(&sibling->active.lock);
+ }
+ GEM_BUG_ON(__tasklet_is_scheduled(&ve->base.execlists.tasklet));
+ GEM_BUG_ON(!list_empty(virtual_queue(ve)));
+
+ if (ve->context.state)
+ __execlists_context_fini(&ve->context);
+ intel_context_fini(&ve->context);
+
+ intel_breadcrumbs_free(ve->base.breadcrumbs);
+ intel_engine_free_request_pool(&ve->base);
+
+ kfree(ve->bonds);
+ kfree(ve);
+}
+
+static void virtual_context_destroy(struct kref *kref)
+{
+ struct virtual_engine *ve =
+ container_of(kref, typeof(*ve), context.ref);
+
+ GEM_BUG_ON(!list_empty(&ve->context.signals));
+
+ /*
+ * When destroying the virtual engine, we have to be aware that
+ * it may still be in use from an hardirq/softirq context causing
+ * the resubmission of a completed request (background completion
+ * due to preempt-to-busy). Before we can free the engine, we need
+ * to flush the submission code and tasklets that are still potentially
+ * accessing the engine. Flushing the tasklets requires process context,
+ * and since we can guard the resubmit onto the engine with an RCU read
+ * lock, we can delegate the free of the engine to an RCU worker.
+ */
+ INIT_RCU_WORK(&ve->rcu, rcu_virtual_context_destroy);
+ queue_rcu_work(system_wq, &ve->rcu);
+}
+
+static void virtual_engine_initial_hint(struct virtual_engine *ve)
+{
+ int swp;
+
+ /*
+ * Pick a random sibling on starting to help spread the load around.
+ *
+ * New contexts are typically created with exactly the same order
+ * of siblings, and often started in batches. Due to the way we iterate
+ * the array of sibling when submitting requests, sibling[0] is
+ * prioritised for dequeuing. If we make sure that sibling[0] is fairly
+ * randomised across the system, we also help spread the load by the
+ * first engine we inspect being different each time.
+ *
+ * NB This does not force us to execute on this engine, it will just
+ * typically be the first we inspect for submission.
+ */
+ swp = prandom_u32_max(ve->num_siblings);
+ if (swp)
+ swap(ve->siblings[swp], ve->siblings[0]);
+}
+
+static int virtual_context_alloc(struct intel_context *ce)
+{
+ struct virtual_engine *ve = container_of(ce, typeof(*ve), context);
+
+ return __execlists_context_alloc(ce, ve->siblings[0]);
+}
+
+static int virtual_context_pin(struct intel_context *ce, void *vaddr)
+{
+ struct virtual_engine *ve = container_of(ce, typeof(*ve), context);
+
+ /* Note: we must use a real engine class for setting up reg state */
+ return __execlists_context_pin(ce, ve->siblings[0], vaddr);
+}
+
+static void virtual_context_enter(struct intel_context *ce)
+{
+ struct virtual_engine *ve = container_of(ce, typeof(*ve), context);
+ unsigned int n;
+
+ for (n = 0; n < ve->num_siblings; n++)
+ intel_engine_pm_get(ve->siblings[n]);
+
+ intel_timeline_enter(ce->timeline);
+}
+
+static void virtual_context_exit(struct intel_context *ce)
+{
+ struct virtual_engine *ve = container_of(ce, typeof(*ve), context);
+ unsigned int n;
+
+ intel_timeline_exit(ce->timeline);
+
+ for (n = 0; n < ve->num_siblings; n++)
+ intel_engine_pm_put(ve->siblings[n]);
+}
+
+static const struct intel_context_ops virtual_context_ops = {
+ .alloc = virtual_context_alloc,
+
+ .pre_pin = execlists_context_pre_pin,
+ .pin = virtual_context_pin,
+ .unpin = execlists_context_unpin,
+ .post_unpin = execlists_context_post_unpin,
+
+ .enter = virtual_context_enter,
+ .exit = virtual_context_exit,
+
+ .destroy = virtual_context_destroy,
+};
+
+static intel_engine_mask_t virtual_submission_mask(struct virtual_engine *ve)
+{
+ struct i915_request *rq;
+ intel_engine_mask_t mask;
+
+ rq = READ_ONCE(ve->request);
+ if (!rq)
+ return 0;
+
+ /* The rq is ready for submission; rq->execution_mask is now stable. */
+ mask = rq->execution_mask;
+ if (unlikely(!mask)) {
+ /* Invalid selection, submit to a random engine in error */
+ i915_request_set_error_once(rq, -ENODEV);
+ mask = ve->siblings[0]->mask;
+ }
+
+ ENGINE_TRACE(&ve->base, "rq=%llx:%lld, mask=%x, prio=%d\n",
+ rq->fence.context, rq->fence.seqno,
+ mask, ve->base.execlists.queue_priority_hint);
+
+ return mask;
+}
+
+static void virtual_submission_tasklet(unsigned long data)
+{
+ struct virtual_engine * const ve = (struct virtual_engine *)data;
+ const int prio = READ_ONCE(ve->base.execlists.queue_priority_hint);
+ intel_engine_mask_t mask;
+ unsigned int n;
+
+ rcu_read_lock();
+ mask = virtual_submission_mask(ve);
+ rcu_read_unlock();
+ if (unlikely(!mask))
+ return;
+
+ local_irq_disable();
+ for (n = 0; n < ve->num_siblings; n++) {
+ struct intel_engine_cs *sibling = READ_ONCE(ve->siblings[n]);
+ struct ve_node * const node = &ve->nodes[sibling->id];
+ struct rb_node **parent, *rb;
+ bool first;
+
+ if (!READ_ONCE(ve->request))
+ break; /* already handled by a sibling's tasklet */
+
+ if (unlikely(!(mask & sibling->mask))) {
+ if (!RB_EMPTY_NODE(&node->rb)) {
+ spin_lock(&sibling->active.lock);
+ rb_erase_cached(&node->rb,
+ &sibling->execlists.virtual);
+ RB_CLEAR_NODE(&node->rb);
+ spin_unlock(&sibling->active.lock);
+ }
+ continue;
+ }
+
+ spin_lock(&sibling->active.lock);
+
+ if (!RB_EMPTY_NODE(&node->rb)) {
+ /*
+ * Cheat and avoid rebalancing the tree if we can
+ * reuse this node in situ.
+ */
+ first = rb_first_cached(&sibling->execlists.virtual) ==
+ &node->rb;
+ if (prio == node->prio || (prio > node->prio && first))
+ goto submit_engine;
+
+ rb_erase_cached(&node->rb, &sibling->execlists.virtual);
+ }
+
+ rb = NULL;
+ first = true;
+ parent = &sibling->execlists.virtual.rb_root.rb_node;
+ while (*parent) {
+ struct ve_node *other;
+
+ rb = *parent;
+ other = rb_entry(rb, typeof(*other), rb);
+ if (prio > other->prio) {
+ parent = &rb->rb_left;
+ } else {
+ parent = &rb->rb_right;
+ first = false;
+ }
+ }
+
+ rb_link_node(&node->rb, rb, parent);
+ rb_insert_color_cached(&node->rb,
+ &sibling->execlists.virtual,
+ first);
+
+submit_engine:
+ GEM_BUG_ON(RB_EMPTY_NODE(&node->rb));
+ node->prio = prio;
+ if (first && prio > sibling->execlists.queue_priority_hint)
+ tasklet_hi_schedule(&sibling->execlists.tasklet);
+
+ spin_unlock(&sibling->active.lock);
+ }
+ local_irq_enable();
+}
+
+static void virtual_submit_request(struct i915_request *rq)
+{
+ struct virtual_engine *ve = to_virtual_engine(rq->engine);
+ struct i915_request *old;
+ unsigned long flags;
+
+ ENGINE_TRACE(&ve->base, "rq=%llx:%lld\n",
+ rq->fence.context,
+ rq->fence.seqno);
+
+ GEM_BUG_ON(ve->base.submit_request != virtual_submit_request);
+
+ spin_lock_irqsave(&ve->base.active.lock, flags);
+
+ old = ve->request;
+ if (old) { /* background completion event from preempt-to-busy */
+ GEM_BUG_ON(!i915_request_completed(old));
+ __i915_request_submit(old);
+ i915_request_put(old);
+ }
+
+ if (i915_request_completed(rq)) {
+ __i915_request_submit(rq);
+
+ ve->base.execlists.queue_priority_hint = INT_MIN;
+ ve->request = NULL;
+ } else {
+ ve->base.execlists.queue_priority_hint = rq_prio(rq);
+ ve->request = i915_request_get(rq);
+
+ GEM_BUG_ON(!list_empty(virtual_queue(ve)));
+ list_move_tail(&rq->sched.link, virtual_queue(ve));
+
+ tasklet_hi_schedule(&ve->base.execlists.tasklet);
+ }
+
+ spin_unlock_irqrestore(&ve->base.active.lock, flags);
+}
+
+static struct ve_bond *
+virtual_find_bond(struct virtual_engine *ve,
+ const struct intel_engine_cs *master)
+{
+ int i;
+
+ for (i = 0; i < ve->num_bonds; i++) {
+ if (ve->bonds[i].master == master)
+ return &ve->bonds[i];
+ }
+
+ return NULL;
+}
+
+static void
+virtual_bond_execute(struct i915_request *rq, struct dma_fence *signal)
+{
+ struct virtual_engine *ve = to_virtual_engine(rq->engine);
+ intel_engine_mask_t allowed, exec;
+ struct ve_bond *bond;
+
+ allowed = ~to_request(signal)->engine->mask;
+
+ bond = virtual_find_bond(ve, to_request(signal)->engine);
+ if (bond)
+ allowed &= bond->sibling_mask;
+
+ /* Restrict the bonded request to run on only the available engines */
+ exec = READ_ONCE(rq->execution_mask);
+ while (!try_cmpxchg(&rq->execution_mask, &exec, exec & allowed))
+ ;
+
+ /* Prevent the master from being re-run on the bonded engines */
+ to_request(signal)->execution_mask &= ~allowed;
+}
+
+struct intel_context *
+intel_execlists_create_virtual(struct intel_engine_cs **siblings,
+ unsigned int count)
+{
+ struct virtual_engine *ve;
+ unsigned int n;
+ int err;
+
+ if (count == 0)
+ return ERR_PTR(-EINVAL);
+
+ if (count == 1)
+ return intel_context_create(siblings[0]);
+
+ ve = kzalloc(struct_size(ve, siblings, count), GFP_KERNEL);
+ if (!ve)
+ return ERR_PTR(-ENOMEM);
+
+ ve->base.i915 = siblings[0]->i915;
+ ve->base.gt = siblings[0]->gt;
+ ve->base.uncore = siblings[0]->uncore;
+ ve->base.id = -1;
+
+ ve->base.class = OTHER_CLASS;
+ ve->base.uabi_class = I915_ENGINE_CLASS_INVALID;
+ ve->base.instance = I915_ENGINE_CLASS_INVALID_VIRTUAL;
+ ve->base.uabi_instance = I915_ENGINE_CLASS_INVALID_VIRTUAL;
+
+ /*
+ * The decision on whether to submit a request using semaphores
+ * depends on the saturated state of the engine. We only compute
+ * this during HW submission of the request, and we need for this
+ * state to be globally applied to all requests being submitted
+ * to this engine. Virtual engines encompass more than one physical
+ * engine and so we cannot accurately tell in advance if one of those
+ * engines is already saturated and so cannot afford to use a semaphore
+ * and be pessimized in priority for doing so -- if we are the only
+ * context using semaphores after all other clients have stopped, we
+ * will be starved on the saturated system. Such a global switch for
+ * semaphores is less than ideal, but alas is the current compromise.
+ */
+ ve->base.saturated = ALL_ENGINES;
+
+ snprintf(ve->base.name, sizeof(ve->base.name), "virtual");
+
+ intel_engine_init_active(&ve->base, ENGINE_VIRTUAL);
+ intel_engine_init_execlists(&ve->base);
+
+ ve->base.cops = &virtual_context_ops;
+ ve->base.request_alloc = execlists_request_alloc;
+
+ ve->base.schedule = i915_schedule;
+ ve->base.submit_request = virtual_submit_request;
+ ve->base.bond_execute = virtual_bond_execute;
+
+ INIT_LIST_HEAD(virtual_queue(ve));
+ ve->base.execlists.queue_priority_hint = INT_MIN;
+ tasklet_init(&ve->base.execlists.tasklet,
+ virtual_submission_tasklet,
+ (unsigned long)ve);
+
+ intel_context_init(&ve->context, &ve->base);
+
+ ve->base.breadcrumbs = intel_breadcrumbs_create(NULL);
+ if (!ve->base.breadcrumbs) {
+ err = -ENOMEM;
+ goto err_put;
+ }
+
+ for (n = 0; n < count; n++) {
+ struct intel_engine_cs *sibling = siblings[n];
+
+ GEM_BUG_ON(!is_power_of_2(sibling->mask));
+ if (sibling->mask & ve->base.mask) {
+ DRM_DEBUG("duplicate %s entry in load balancer\n",
+ sibling->name);
+ err = -EINVAL;
+ goto err_put;
+ }
+
+ /*
+ * The virtual engine implementation is tightly coupled to
+ * the execlists backend -- we push out request directly
+ * into a tree inside each physical engine. We could support
+ * layering if we handle cloning of the requests and
+ * submitting a copy into each backend.
+ */
+ if (sibling->execlists.tasklet.func !=
+ execlists_submission_tasklet) {
+ err = -ENODEV;
+ goto err_put;
+ }
+
+ GEM_BUG_ON(RB_EMPTY_NODE(&ve->nodes[sibling->id].rb));
+ RB_CLEAR_NODE(&ve->nodes[sibling->id].rb);
+
+ ve->siblings[ve->num_siblings++] = sibling;
+ ve->base.mask |= sibling->mask;
+
+ /*
+ * All physical engines must be compatible for their emission
+ * functions (as we build the instructions during request
+ * construction and do not alter them before submission
+ * on the physical engine). We use the engine class as a guide
+ * here, although that could be refined.
+ */
+ if (ve->base.class != OTHER_CLASS) {
+ if (ve->base.class != sibling->class) {
+ DRM_DEBUG("invalid mixing of engine class, sibling %d, already %d\n",
+ sibling->class, ve->base.class);
+ err = -EINVAL;
+ goto err_put;
+ }
+ continue;
+ }
+
+ ve->base.class = sibling->class;
+ ve->base.uabi_class = sibling->uabi_class;
+ snprintf(ve->base.name, sizeof(ve->base.name),
+ "v%dx%d", ve->base.class, count);
+ ve->base.context_size = sibling->context_size;
+
+ ve->base.emit_bb_start = sibling->emit_bb_start;
+ ve->base.emit_flush = sibling->emit_flush;
+ ve->base.emit_init_breadcrumb = sibling->emit_init_breadcrumb;
+ ve->base.emit_fini_breadcrumb = sibling->emit_fini_breadcrumb;
+ ve->base.emit_fini_breadcrumb_dw =
+ sibling->emit_fini_breadcrumb_dw;
+
+ ve->base.flags = sibling->flags;
+ }
+
+ ve->base.flags |= I915_ENGINE_IS_VIRTUAL;
+
+ virtual_engine_initial_hint(ve);
+ return &ve->context;
+
+err_put:
+ intel_context_put(&ve->context);
+ return ERR_PTR(err);
+}
+
+struct intel_context *
+intel_execlists_clone_virtual(struct intel_engine_cs *src)
+{
+ struct virtual_engine *se = to_virtual_engine(src);
+ struct intel_context *dst;
+
+ dst = intel_execlists_create_virtual(se->siblings,
+ se->num_siblings);
+ if (IS_ERR(dst))
+ return dst;
+
+ if (se->num_bonds) {
+ struct virtual_engine *de = to_virtual_engine(dst->engine);
+
+ de->bonds = kmemdup(se->bonds,
+ sizeof(*se->bonds) * se->num_bonds,
+ GFP_KERNEL);
+ if (!de->bonds) {
+ intel_context_put(dst);
+ return ERR_PTR(-ENOMEM);
+ }
+
+ de->num_bonds = se->num_bonds;
+ }
+
+ return dst;
+}
+
+int intel_virtual_engine_attach_bond(struct intel_engine_cs *engine,
+ const struct intel_engine_cs *master,
+ const struct intel_engine_cs *sibling)
+{
+ struct virtual_engine *ve = to_virtual_engine(engine);
+ struct ve_bond *bond;
+ int n;
+
+ /* Sanity check the sibling is part of the virtual engine */
+ for (n = 0; n < ve->num_siblings; n++)
+ if (sibling == ve->siblings[n])
+ break;
+ if (n == ve->num_siblings)
+ return -EINVAL;
+
+ bond = virtual_find_bond(ve, master);
+ if (bond) {
+ bond->sibling_mask |= sibling->mask;
+ return 0;
+ }
+
+ bond = krealloc(ve->bonds,
+ sizeof(*bond) * (ve->num_bonds + 1),
+ GFP_KERNEL);
+ if (!bond)
+ return -ENOMEM;
+
+ bond[ve->num_bonds].master = master;
+ bond[ve->num_bonds].sibling_mask = sibling->mask;
+
+ ve->bonds = bond;
+ ve->num_bonds++;
+
+ return 0;
+}
+
+void intel_execlists_show_requests(struct intel_engine_cs *engine,
+ struct drm_printer *m,
+ void (*show_request)(struct drm_printer *m,
+ const struct i915_request *rq,
+ const char *prefix,
+ int indent),
+ unsigned int max)
+{
+ const struct intel_engine_execlists *execlists = &engine->execlists;
+ struct i915_request *rq, *last;
+ unsigned long flags;
+ unsigned int count;
+ struct rb_node *rb;
+
+ spin_lock_irqsave(&engine->active.lock, flags);
+
+ last = NULL;
+ count = 0;
+ list_for_each_entry(rq, &engine->active.requests, sched.link) {
+ if (count++ < max - 1)
+ show_request(m, rq, "\t\t", 0);
+ else
+ last = rq;
+ }
+ if (last) {
+ if (count > max) {
+ drm_printf(m,
+ "\t\t...skipping %d executing requests...\n",
+ count - max);
+ }
+ show_request(m, last, "\t\t", 0);
+ }
+
+ if (execlists->switch_priority_hint != INT_MIN)
+ drm_printf(m, "\t\tSwitch priority hint: %d\n",
+ READ_ONCE(execlists->switch_priority_hint));
+ if (execlists->queue_priority_hint != INT_MIN)
+ drm_printf(m, "\t\tQueue priority hint: %d\n",
+ READ_ONCE(execlists->queue_priority_hint));
+
+ last = NULL;
+ count = 0;
+ for (rb = rb_first_cached(&execlists->queue); rb; rb = rb_next(rb)) {
+ struct i915_priolist *p = rb_entry(rb, typeof(*p), node);
+ int i;
+
+ priolist_for_each_request(rq, p, i) {
+ if (count++ < max - 1)
+ show_request(m, rq, "\t\t", 0);
+ else
+ last = rq;
+ }
+ }
+ if (last) {
+ if (count > max) {
+ drm_printf(m,
+ "\t\t...skipping %d queued requests...\n",
+ count - max);
+ }
+ show_request(m, last, "\t\t", 0);
+ }
+
+ last = NULL;
+ count = 0;
+ for (rb = rb_first_cached(&execlists->virtual); rb; rb = rb_next(rb)) {
+ struct virtual_engine *ve =
+ rb_entry(rb, typeof(*ve), nodes[engine->id].rb);
+ struct i915_request *rq = READ_ONCE(ve->request);
+
+ if (rq) {
+ if (count++ < max - 1)
+ show_request(m, rq, "\t\t", 0);
+ else
+ last = rq;
+ }
+ }
+ if (last) {
+ if (count > max) {
+ drm_printf(m,
+ "\t\t...skipping %d virtual requests...\n",
+ count - max);
+ }
+ show_request(m, last, "\t\t", 0);
+ }
+
+ spin_unlock_irqrestore(&engine->active.lock, flags);
+}
+
+void intel_lr_context_reset(struct intel_engine_cs *engine,
+ struct intel_context *ce,
+ u32 head,
+ bool scrub)
+{
+ GEM_BUG_ON(!intel_context_is_pinned(ce));
+
+ /*
+ * We want a simple context + ring to execute the breadcrumb update.
+ * We cannot rely on the context being intact across the GPU hang,
+ * so clear it and rebuild just what we need for the breadcrumb.
+ * All pending requests for this context will be zapped, and any
+ * future request will be after userspace has had the opportunity
+ * to recreate its own state.
+ */
+ if (scrub)
+ restore_default_state(ce, engine);
+
+ /* Rerun the request; its payload has been neutered (if guilty). */
+ __execlists_update_reg_state(ce, engine, head);
+}
+
+bool
+intel_engine_in_execlists_submission_mode(const struct intel_engine_cs *engine)
+{
+ return engine->set_default_submission ==
+ intel_execlists_set_default_submission;
+}
+
+#if IS_ENABLED(CONFIG_DRM_I915_SELFTEST)
+#include "selftest_execlists.c"
+#endif