diff options
Diffstat (limited to 'drivers/gpu/drm/i915/gt/uc/intel_guc_submission.c')
| -rw-r--r-- | drivers/gpu/drm/i915/gt/uc/intel_guc_submission.c | 1184 |
1 files changed, 1184 insertions, 0 deletions
diff --git a/drivers/gpu/drm/i915/gt/uc/intel_guc_submission.c b/drivers/gpu/drm/i915/gt/uc/intel_guc_submission.c new file mode 100644 index 000000000000..f325d3dd564f --- /dev/null +++ b/drivers/gpu/drm/i915/gt/uc/intel_guc_submission.c @@ -0,0 +1,1184 @@ +// SPDX-License-Identifier: MIT +/* + * Copyright © 2014 Intel Corporation + */ + +#include <linux/circ_buf.h> + +#include "gem/i915_gem_context.h" + +#include "gt/intel_context.h" +#include "gt/intel_engine_pm.h" +#include "gt/intel_gt.h" +#include "gt/intel_gt_pm.h" +#include "gt/intel_lrc_reg.h" +#include "intel_guc_submission.h" + +#include "i915_drv.h" +#include "i915_trace.h" + +enum { + GUC_PREEMPT_NONE = 0, + GUC_PREEMPT_INPROGRESS, + GUC_PREEMPT_FINISHED, +}; +#define GUC_PREEMPT_BREADCRUMB_DWORDS 0x8 +#define GUC_PREEMPT_BREADCRUMB_BYTES \ + (sizeof(u32) * GUC_PREEMPT_BREADCRUMB_DWORDS) + +/** + * DOC: GuC-based command submission + * + * GuC client: + * A intel_guc_client refers to a submission path through GuC. Currently, there + * is only one client, which is charged with all submissions to the GuC. This + * struct is the owner of a doorbell, a process descriptor and a workqueue (all + * of them inside a single gem object that contains all required pages for these + * elements). + * + * GuC stage descriptor: + * During initialization, the driver allocates a static pool of 1024 such + * descriptors, and shares them with the GuC. + * Currently, there exists a 1:1 mapping between a intel_guc_client and a + * guc_stage_desc (via the client's stage_id), so effectively only one + * gets used. This stage descriptor lets the GuC know about the doorbell, + * workqueue and process descriptor. Theoretically, it also lets the GuC + * know about our HW contexts (context ID, etc...), but we actually + * employ a kind of submission where the GuC uses the LRCA sent via the work + * item instead (the single guc_stage_desc associated to execbuf client + * contains information about the default kernel context only, but this is + * essentially unused). This is called a "proxy" submission. + * + * The Scratch registers: + * There are 16 MMIO-based registers start from 0xC180. The kernel driver writes + * a value to the action register (SOFT_SCRATCH_0) along with any data. It then + * triggers an interrupt on the GuC via another register write (0xC4C8). + * Firmware writes a success/fail code back to the action register after + * processes the request. The kernel driver polls waiting for this update and + * then proceeds. + * See intel_guc_send() + * + * Doorbells: + * Doorbells are interrupts to uKernel. A doorbell is a single cache line (QW) + * mapped into process space. + * + * Work Items: + * There are several types of work items that the host may place into a + * workqueue, each with its own requirements and limitations. Currently only + * WQ_TYPE_INORDER is needed to support legacy submission via GuC, which + * represents in-order queue. The kernel driver packs ring tail pointer and an + * ELSP context descriptor dword into Work Item. + * See guc_add_request() + * + */ + +static inline struct i915_priolist *to_priolist(struct rb_node *rb) +{ + return rb_entry(rb, struct i915_priolist, node); +} + +static inline bool is_high_priority(struct intel_guc_client *client) +{ + return (client->priority == GUC_CLIENT_PRIORITY_KMD_HIGH || + client->priority == GUC_CLIENT_PRIORITY_HIGH); +} + +static int reserve_doorbell(struct intel_guc_client *client) +{ + unsigned long offset; + unsigned long end; + u16 id; + + GEM_BUG_ON(client->doorbell_id != GUC_DOORBELL_INVALID); + + /* + * The bitmap tracks which doorbell registers are currently in use. + * It is split into two halves; the first half is used for normal + * priority contexts, the second half for high-priority ones. + */ + offset = 0; + end = GUC_NUM_DOORBELLS / 2; + if (is_high_priority(client)) { + offset = end; + end += offset; + } + + id = find_next_zero_bit(client->guc->doorbell_bitmap, end, offset); + if (id == end) + return -ENOSPC; + + __set_bit(id, client->guc->doorbell_bitmap); + client->doorbell_id = id; + DRM_DEBUG_DRIVER("client %u (high prio=%s) reserved doorbell: %d\n", + client->stage_id, yesno(is_high_priority(client)), + id); + return 0; +} + +static bool has_doorbell(struct intel_guc_client *client) +{ + if (client->doorbell_id == GUC_DOORBELL_INVALID) + return false; + + return test_bit(client->doorbell_id, client->guc->doorbell_bitmap); +} + +static void unreserve_doorbell(struct intel_guc_client *client) +{ + GEM_BUG_ON(!has_doorbell(client)); + + __clear_bit(client->doorbell_id, client->guc->doorbell_bitmap); + client->doorbell_id = GUC_DOORBELL_INVALID; +} + +/* + * Tell the GuC to allocate or deallocate a specific doorbell + */ + +static int __guc_allocate_doorbell(struct intel_guc *guc, u32 stage_id) +{ + u32 action[] = { + INTEL_GUC_ACTION_ALLOCATE_DOORBELL, + stage_id + }; + + return intel_guc_send(guc, action, ARRAY_SIZE(action)); +} + +static int __guc_deallocate_doorbell(struct intel_guc *guc, u32 stage_id) +{ + u32 action[] = { + INTEL_GUC_ACTION_DEALLOCATE_DOORBELL, + stage_id + }; + + return intel_guc_send(guc, action, ARRAY_SIZE(action)); +} + +static struct guc_stage_desc *__get_stage_desc(struct intel_guc_client *client) +{ + struct guc_stage_desc *base = client->guc->stage_desc_pool_vaddr; + + return &base[client->stage_id]; +} + +/* + * Initialise, update, or clear doorbell data shared with the GuC + * + * These functions modify shared data and so need access to the mapped + * client object which contains the page being used for the doorbell + */ + +static void __update_doorbell_desc(struct intel_guc_client *client, u16 new_id) +{ + struct guc_stage_desc *desc; + + /* Update the GuC's idea of the doorbell ID */ + desc = __get_stage_desc(client); + desc->db_id = new_id; +} + +static struct guc_doorbell_info *__get_doorbell(struct intel_guc_client *client) +{ + return client->vaddr + client->doorbell_offset; +} + +static bool __doorbell_valid(struct intel_guc *guc, u16 db_id) +{ + struct intel_uncore *uncore = guc_to_gt(guc)->uncore; + + GEM_BUG_ON(db_id >= GUC_NUM_DOORBELLS); + return intel_uncore_read(uncore, GEN8_DRBREGL(db_id)) & GEN8_DRB_VALID; +} + +static void __init_doorbell(struct intel_guc_client *client) +{ + struct guc_doorbell_info *doorbell; + + doorbell = __get_doorbell(client); + doorbell->db_status = GUC_DOORBELL_ENABLED; + doorbell->cookie = 0; +} + +static void __fini_doorbell(struct intel_guc_client *client) +{ + struct guc_doorbell_info *doorbell; + u16 db_id = client->doorbell_id; + + doorbell = __get_doorbell(client); + doorbell->db_status = GUC_DOORBELL_DISABLED; + + /* Doorbell release flow requires that we wait for GEN8_DRB_VALID bit + * to go to zero after updating db_status before we call the GuC to + * release the doorbell + */ + if (wait_for_us(!__doorbell_valid(client->guc, db_id), 10)) + WARN_ONCE(true, "Doorbell never became invalid after disable\n"); +} + +static int create_doorbell(struct intel_guc_client *client) +{ + int ret; + + if (WARN_ON(!has_doorbell(client))) + return -ENODEV; /* internal setup error, should never happen */ + + __update_doorbell_desc(client, client->doorbell_id); + __init_doorbell(client); + + ret = __guc_allocate_doorbell(client->guc, client->stage_id); + if (ret) { + __fini_doorbell(client); + __update_doorbell_desc(client, GUC_DOORBELL_INVALID); + DRM_DEBUG_DRIVER("Couldn't create client %u doorbell: %d\n", + client->stage_id, ret); + return ret; + } + + return 0; +} + +static int destroy_doorbell(struct intel_guc_client *client) +{ + int ret; + + GEM_BUG_ON(!has_doorbell(client)); + + __fini_doorbell(client); + ret = __guc_deallocate_doorbell(client->guc, client->stage_id); + if (ret) + DRM_ERROR("Couldn't destroy client %u doorbell: %d\n", + client->stage_id, ret); + + __update_doorbell_desc(client, GUC_DOORBELL_INVALID); + + return ret; +} + +static unsigned long __select_cacheline(struct intel_guc *guc) +{ + unsigned long offset; + + /* Doorbell uses a single cache line within a page */ + offset = offset_in_page(guc->db_cacheline); + + /* Moving to next cache line to reduce contention */ + guc->db_cacheline += cache_line_size(); + + DRM_DEBUG_DRIVER("reserved cacheline 0x%lx, next 0x%x, linesize %u\n", + offset, guc->db_cacheline, cache_line_size()); + return offset; +} + +static inline struct guc_process_desc * +__get_process_desc(struct intel_guc_client *client) +{ + return client->vaddr + client->proc_desc_offset; +} + +/* + * Initialise the process descriptor shared with the GuC firmware. + */ +static void guc_proc_desc_init(struct intel_guc_client *client) +{ + struct guc_process_desc *desc; + + desc = memset(__get_process_desc(client), 0, sizeof(*desc)); + + /* + * XXX: pDoorbell and WQVBaseAddress are pointers in process address + * space for ring3 clients (set them as in mmap_ioctl) or kernel + * space for kernel clients (map on demand instead? May make debug + * easier to have it mapped). + */ + desc->wq_base_addr = 0; + desc->db_base_addr = 0; + + desc->stage_id = client->stage_id; + desc->wq_size_bytes = GUC_WQ_SIZE; + desc->wq_status = WQ_STATUS_ACTIVE; + desc->priority = client->priority; +} + +static void guc_proc_desc_fini(struct intel_guc_client *client) +{ + struct guc_process_desc *desc; + + desc = __get_process_desc(client); + memset(desc, 0, sizeof(*desc)); +} + +static int guc_stage_desc_pool_create(struct intel_guc *guc) +{ + struct i915_vma *vma; + void *vaddr; + + vma = intel_guc_allocate_vma(guc, + PAGE_ALIGN(sizeof(struct guc_stage_desc) * + GUC_MAX_STAGE_DESCRIPTORS)); + if (IS_ERR(vma)) + return PTR_ERR(vma); + + vaddr = i915_gem_object_pin_map(vma->obj, I915_MAP_WB); + if (IS_ERR(vaddr)) { + i915_vma_unpin_and_release(&vma, 0); + return PTR_ERR(vaddr); + } + + guc->stage_desc_pool = vma; + guc->stage_desc_pool_vaddr = vaddr; + ida_init(&guc->stage_ids); + + return 0; +} + +static void guc_stage_desc_pool_destroy(struct intel_guc *guc) +{ + ida_destroy(&guc->stage_ids); + i915_vma_unpin_and_release(&guc->stage_desc_pool, I915_VMA_RELEASE_MAP); +} + +/* + * Initialise/clear the stage descriptor shared with the GuC firmware. + * + * This descriptor tells the GuC where (in GGTT space) to find the important + * data structures relating to this client (doorbell, process descriptor, + * write queue, etc). + */ +static void guc_stage_desc_init(struct intel_guc_client *client) +{ + struct intel_guc *guc = client->guc; + struct guc_stage_desc *desc; + u32 gfx_addr; + + desc = __get_stage_desc(client); + memset(desc, 0, sizeof(*desc)); + + desc->attribute = GUC_STAGE_DESC_ATTR_ACTIVE | + GUC_STAGE_DESC_ATTR_KERNEL; + if (is_high_priority(client)) + desc->attribute |= GUC_STAGE_DESC_ATTR_PREEMPT; + desc->stage_id = client->stage_id; + desc->priority = client->priority; + desc->db_id = client->doorbell_id; + + /* + * The doorbell, process descriptor, and workqueue are all parts + * of the client object, which the GuC will reference via the GGTT + */ + gfx_addr = intel_guc_ggtt_offset(guc, client->vma); + desc->db_trigger_phy = sg_dma_address(client->vma->pages->sgl) + + client->doorbell_offset; + desc->db_trigger_cpu = ptr_to_u64(__get_doorbell(client)); + desc->db_trigger_uk = gfx_addr + client->doorbell_offset; + desc->process_desc = gfx_addr + client->proc_desc_offset; + desc->wq_addr = gfx_addr + GUC_DB_SIZE; + desc->wq_size = GUC_WQ_SIZE; + + desc->desc_private = ptr_to_u64(client); +} + +static void guc_stage_desc_fini(struct intel_guc_client *client) +{ + struct guc_stage_desc *desc; + + desc = __get_stage_desc(client); + memset(desc, 0, sizeof(*desc)); +} + +/* Construct a Work Item and append it to the GuC's Work Queue */ +static void guc_wq_item_append(struct intel_guc_client *client, + u32 target_engine, u32 context_desc, + u32 ring_tail, u32 fence_id) +{ + /* wqi_len is in DWords, and does not include the one-word header */ + const size_t wqi_size = sizeof(struct guc_wq_item); + const u32 wqi_len = wqi_size / sizeof(u32) - 1; + struct guc_process_desc *desc = __get_process_desc(client); + struct guc_wq_item *wqi; + u32 wq_off; + + lockdep_assert_held(&client->wq_lock); + + /* For now workqueue item is 4 DWs; workqueue buffer is 2 pages. So we + * should not have the case where structure wqi is across page, neither + * wrapped to the beginning. This simplifies the implementation below. + * + * XXX: if not the case, we need save data to a temp wqi and copy it to + * workqueue buffer dw by dw. + */ + BUILD_BUG_ON(wqi_size != 16); + + /* We expect the WQ to be active if we're appending items to it */ + GEM_BUG_ON(desc->wq_status != WQ_STATUS_ACTIVE); + + /* Free space is guaranteed. */ + wq_off = READ_ONCE(desc->tail); + GEM_BUG_ON(CIRC_SPACE(wq_off, READ_ONCE(desc->head), + GUC_WQ_SIZE) < wqi_size); + GEM_BUG_ON(wq_off & (wqi_size - 1)); + + /* WQ starts from the page after doorbell / process_desc */ + wqi = client->vaddr + wq_off + GUC_DB_SIZE; + + if (I915_SELFTEST_ONLY(client->use_nop_wqi)) { + wqi->header = WQ_TYPE_NOOP | (wqi_len << WQ_LEN_SHIFT); + } else { + /* Now fill in the 4-word work queue item */ + wqi->header = WQ_TYPE_INORDER | + (wqi_len << WQ_LEN_SHIFT) | + (target_engine << WQ_TARGET_SHIFT) | + WQ_NO_WCFLUSH_WAIT; + wqi->context_desc = context_desc; + wqi->submit_element_info = ring_tail << WQ_RING_TAIL_SHIFT; + GEM_BUG_ON(ring_tail > WQ_RING_TAIL_MAX); + wqi->fence_id = fence_id; + } + + /* Make the update visible to GuC */ + WRITE_ONCE(desc->tail, (wq_off + wqi_size) & (GUC_WQ_SIZE - 1)); +} + +static void guc_ring_doorbell(struct intel_guc_client *client) +{ + struct guc_doorbell_info *db; + u32 cookie; + + lockdep_assert_held(&client->wq_lock); + + /* pointer of current doorbell cacheline */ + db = __get_doorbell(client); + + /* + * We're not expecting the doorbell cookie to change behind our back, + * we also need to treat 0 as a reserved value. + */ + cookie = READ_ONCE(db->cookie); + WARN_ON_ONCE(xchg(&db->cookie, cookie + 1 ?: cookie + 2) != cookie); + + /* XXX: doorbell was lost and need to acquire it again */ + GEM_BUG_ON(db->db_status != GUC_DOORBELL_ENABLED); +} + +static void guc_add_request(struct intel_guc *guc, struct i915_request *rq) +{ + struct intel_guc_client *client = guc->execbuf_client; + struct intel_engine_cs *engine = rq->engine; + u32 ctx_desc = lower_32_bits(rq->hw_context->lrc_desc); + u32 ring_tail = intel_ring_set_tail(rq->ring, rq->tail) / sizeof(u64); + + guc_wq_item_append(client, engine->guc_id, ctx_desc, + ring_tail, rq->fence.seqno); + guc_ring_doorbell(client); +} + +/* + * When we're doing submissions using regular execlists backend, writing to + * ELSP from CPU side is enough to make sure that writes to ringbuffer pages + * pinned in mappable aperture portion of GGTT are visible to command streamer. + * Writes done by GuC on our behalf are not guaranteeing such ordering, + * therefore, to ensure the flush, we're issuing a POSTING READ. + */ +static void flush_ggtt_writes(struct i915_vma *vma) +{ + struct drm_i915_private *i915 = vma->vm->i915; + + if (i915_vma_is_map_and_fenceable(vma)) + intel_uncore_posting_read_fw(&i915->uncore, GUC_STATUS); +} + +static void guc_submit(struct intel_engine_cs *engine, + struct i915_request **out, + struct i915_request **end) +{ + struct intel_guc *guc = &engine->gt->uc.guc; + struct intel_guc_client *client = guc->execbuf_client; + + spin_lock(&client->wq_lock); + + do { + struct i915_request *rq = *out++; + + flush_ggtt_writes(rq->ring->vma); + guc_add_request(guc, rq); + } while (out != end); + + spin_unlock(&client->wq_lock); +} + +static inline int rq_prio(const struct i915_request *rq) +{ + return rq->sched.attr.priority | __NO_PREEMPTION; +} + +static struct i915_request *schedule_in(struct i915_request *rq, int idx) +{ + trace_i915_request_in(rq, idx); + + /* + * Currently we are not tracking the rq->context being inflight + * (ce->inflight = rq->engine). It is only used by the execlists + * backend at the moment, a similar counting strategy would be + * required if we generalise the inflight tracking. + */ + + intel_gt_pm_get(rq->engine->gt); + return i915_request_get(rq); +} + +static void schedule_out(struct i915_request *rq) +{ + trace_i915_request_out(rq); + + intel_gt_pm_put(rq->engine->gt); + i915_request_put(rq); +} + +static void __guc_dequeue(struct intel_engine_cs *engine) +{ + struct intel_engine_execlists * const execlists = &engine->execlists; + struct i915_request **first = execlists->inflight; + struct i915_request ** const last_port = first + execlists->port_mask; + struct i915_request *last = first[0]; + struct i915_request **port; + bool submit = false; + struct rb_node *rb; + + lockdep_assert_held(&engine->active.lock); + + if (last) { + if (*++first) + return; + + last = NULL; + } + + /* + * We write directly into the execlists->inflight queue and don't use + * the execlists->pending queue, as we don't have a distinct switch + * event. + */ + port = first; + 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) { + if (last && rq->hw_context != last->hw_context) { + if (port == last_port) + goto done; + + *port = schedule_in(last, + port - execlists->inflight); + port++; + } + + list_del_init(&rq->sched.link); + __i915_request_submit(rq); + submit = true; + last = rq; + } + + rb_erase_cached(&p->node, &execlists->queue); + i915_priolist_free(p); + } +done: + execlists->queue_priority_hint = + rb ? to_priolist(rb)->priority : INT_MIN; + if (submit) { + *port = schedule_in(last, port - execlists->inflight); + *++port = NULL; + guc_submit(engine, first, port); + } + execlists->active = execlists->inflight; +} + +static void guc_submission_tasklet(unsigned long data) +{ + struct intel_engine_cs * const engine = (struct intel_engine_cs *)data; + struct intel_engine_execlists * const execlists = &engine->execlists; + struct i915_request **port, *rq; + unsigned long flags; + + spin_lock_irqsave(&engine->active.lock, flags); + + for (port = execlists->inflight; (rq = *port); port++) { + if (!i915_request_completed(rq)) + break; + + schedule_out(rq); + } + if (port != execlists->inflight) { + int idx = port - execlists->inflight; + int rem = ARRAY_SIZE(execlists->inflight) - idx; + memmove(execlists->inflight, port, rem * sizeof(*port)); + } + + __guc_dequeue(engine); + + spin_unlock_irqrestore(&engine->active.lock, flags); +} + +static void guc_reset_prepare(struct intel_engine_cs *engine) +{ + struct intel_engine_execlists * const execlists = &engine->execlists; + + GEM_TRACE("%s\n", engine->name); + + /* + * 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->init_hw() and also writing the ELSP. + * Turning off the execlists->tasklet until the reset is over + * prevents the race. + */ + __tasklet_disable_sync_once(&execlists->tasklet); +} + +static void +cancel_port_requests(struct intel_engine_execlists * const execlists) +{ + struct i915_request * const *port, *rq; + + /* Note we are only using the inflight and not the pending queue */ + + for (port = execlists->active; (rq = *port); port++) + schedule_out(rq); + execlists->active = + memset(execlists->inflight, 0, sizeof(execlists->inflight)); +} + +static void guc_reset(struct intel_engine_cs *engine, bool stalled) +{ + struct intel_engine_execlists * const execlists = &engine->execlists; + struct i915_request *rq; + unsigned long flags; + + spin_lock_irqsave(&engine->active.lock, flags); + + cancel_port_requests(execlists); + + /* Push back any incomplete requests for replay after the reset. */ + rq = execlists_unwind_incomplete_requests(execlists); + if (!rq) + goto out_unlock; + + if (!i915_request_started(rq)) + stalled = false; + + __i915_request_reset(rq, stalled); + intel_lr_context_reset(engine, rq->hw_context, rq->head, stalled); + +out_unlock: + spin_unlock_irqrestore(&engine->active.lock, flags); +} + +static void guc_cancel_requests(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; + + GEM_TRACE("%s\n", engine->name); + + /* + * 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); + + /* Cancel the requests on the HW and clear the ELSP tracker. */ + cancel_port_requests(execlists); + + /* Mark all executing requests as skipped. */ + list_for_each_entry(rq, &engine->active.requests, sched.link) { + if (!i915_request_signaled(rq)) + dma_fence_set_error(&rq->fence, -EIO); + + i915_request_mark_complete(rq); + } + + /* 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) { + list_del_init(&rq->sched.link); + __i915_request_submit(rq); + dma_fence_set_error(&rq->fence, -EIO); + i915_request_mark_complete(rq); + } + + rb_erase_cached(&p->node, &execlists->queue); + i915_priolist_free(p); + } + + /* Remaining _unready_ requests will be nop'ed when submitted */ + + execlists->queue_priority_hint = INT_MIN; + execlists->queue = RB_ROOT_CACHED; + + spin_unlock_irqrestore(&engine->active.lock, flags); +} + +static void guc_reset_finish(struct intel_engine_cs *engine) +{ + struct intel_engine_execlists * const execlists = &engine->execlists; + + if (__tasklet_enable(&execlists->tasklet)) + /* And kick in case we missed a new request submission. */ + tasklet_hi_schedule(&execlists->tasklet); + + GEM_TRACE("%s: depth->%d\n", engine->name, + atomic_read(&execlists->tasklet.count)); +} + +/* + * Everything below here is concerned with setup & teardown, and is + * therefore not part of the somewhat time-critical batch-submission + * path of guc_submit() above. + */ + +/* Check that a doorbell register is in the expected state */ +static bool doorbell_ok(struct intel_guc *guc, u16 db_id) +{ + bool valid; + + GEM_BUG_ON(db_id >= GUC_NUM_DOORBELLS); + + valid = __doorbell_valid(guc, db_id); + + if (test_bit(db_id, guc->doorbell_bitmap) == valid) + return true; + + DRM_DEBUG_DRIVER("Doorbell %u has unexpected state: valid=%s\n", + db_id, yesno(valid)); + + return false; +} + +static bool guc_verify_doorbells(struct intel_guc *guc) +{ + bool doorbells_ok = true; + u16 db_id; + + for (db_id = 0; db_id < GUC_NUM_DOORBELLS; ++db_id) + if (!doorbell_ok(guc, db_id)) + doorbells_ok = false; + + return doorbells_ok; +} + +/** + * guc_client_alloc() - Allocate an intel_guc_client + * @guc: the intel_guc structure + * @priority: four levels priority _CRITICAL, _HIGH, _NORMAL and _LOW + * The kernel client to replace ExecList submission is created with + * NORMAL priority. Priority of a client for scheduler can be HIGH, + * while a preemption context can use CRITICAL. + * + * Return: An intel_guc_client object if success, else NULL. + */ +static struct intel_guc_client * +guc_client_alloc(struct intel_guc *guc, u32 priority) +{ + struct intel_guc_client *client; + struct i915_vma *vma; + void *vaddr; + int ret; + + client = kzalloc(sizeof(*client), GFP_KERNEL); + if (!client) + return ERR_PTR(-ENOMEM); + + client->guc = guc; + client->priority = priority; + client->doorbell_id = GUC_DOORBELL_INVALID; + spin_lock_init(&client->wq_lock); + + ret = ida_simple_get(&guc->stage_ids, 0, GUC_MAX_STAGE_DESCRIPTORS, + GFP_KERNEL); + if (ret < 0) + goto err_client; + + client->stage_id = ret; + + /* The first page is doorbell/proc_desc. Two followed pages are wq. */ + vma = intel_guc_allocate_vma(guc, GUC_DB_SIZE + GUC_WQ_SIZE); + if (IS_ERR(vma)) { + ret = PTR_ERR(vma); + goto err_id; + } + + /* We'll keep just the first (doorbell/proc) page permanently kmap'd. */ + client->vma = vma; + + vaddr = i915_gem_object_pin_map(vma->obj, I915_MAP_WB); + if (IS_ERR(vaddr)) { + ret = PTR_ERR(vaddr); + goto err_vma; + } + client->vaddr = vaddr; + + ret = reserve_doorbell(client); + if (ret) + goto err_vaddr; + + client->doorbell_offset = __select_cacheline(guc); + + /* + * Since the doorbell only requires a single cacheline, we can save + * space by putting the application process descriptor in the same + * page. Use the half of the page that doesn't include the doorbell. + */ + if (client->doorbell_offset >= (GUC_DB_SIZE / 2)) + client->proc_desc_offset = 0; + else + client->proc_desc_offset = (GUC_DB_SIZE / 2); + + DRM_DEBUG_DRIVER("new priority %u client %p: stage_id %u\n", + priority, client, client->stage_id); + DRM_DEBUG_DRIVER("doorbell id %u, cacheline offset 0x%lx\n", + client->doorbell_id, client->doorbell_offset); + + return client; + +err_vaddr: + i915_gem_object_unpin_map(client->vma->obj); +err_vma: + i915_vma_unpin_and_release(&client->vma, 0); +err_id: + ida_simple_remove(&guc->stage_ids, client->stage_id); +err_client: + kfree(client); + return ERR_PTR(ret); +} + +static void guc_client_free(struct intel_guc_client *client) +{ + unreserve_doorbell(client); + i915_vma_unpin_and_release(&client->vma, I915_VMA_RELEASE_MAP); + ida_simple_remove(&client->guc->stage_ids, client->stage_id); + kfree(client); +} + +static inline bool ctx_save_restore_disabled(struct intel_context *ce) +{ + u32 sr = ce->lrc_reg_state[CTX_CONTEXT_CONTROL + 1]; + +#define SR_DISABLED \ + _MASKED_BIT_ENABLE(CTX_CTRL_ENGINE_CTX_RESTORE_INHIBIT | \ + CTX_CTRL_ENGINE_CTX_SAVE_INHIBIT) + + return (sr & SR_DISABLED) == SR_DISABLED; + +#undef SR_DISABLED +} + +static int guc_clients_create(struct intel_guc *guc) +{ + struct intel_guc_client *client; + + GEM_BUG_ON(guc->execbuf_client); + + client = guc_client_alloc(guc, GUC_CLIENT_PRIORITY_KMD_NORMAL); + if (IS_ERR(client)) { + DRM_ERROR("Failed to create GuC client for submission!\n"); + return PTR_ERR(client); + } + guc->execbuf_client = client; + + return 0; +} + +static void guc_clients_destroy(struct intel_guc *guc) +{ + struct intel_guc_client *client; + + client = fetch_and_zero(&guc->execbuf_client); + if (client) + guc_client_free(client); +} + +static int __guc_client_enable(struct intel_guc_client *client) +{ + int ret; + + guc_proc_desc_init(client); + guc_stage_desc_init(client); + + ret = create_doorbell(client); + if (ret) + goto fail; + + return 0; + +fail: + guc_stage_desc_fini(client); + guc_proc_desc_fini(client); + return ret; +} + +static void __guc_client_disable(struct intel_guc_client *client) +{ + /* + * By the time we're here, GuC may have already been reset. if that is + * the case, instead of trying (in vain) to communicate with it, let's + * just cleanup the doorbell HW and our internal state. + */ + if (intel_guc_is_running(client->guc)) + destroy_doorbell(client); + else + __fini_doorbell(client); + + guc_stage_desc_fini(client); + guc_proc_desc_fini(client); +} + +static int guc_clients_enable(struct intel_guc *guc) +{ + return __guc_client_enable(guc->execbuf_client); +} + +static void guc_clients_disable(struct intel_guc *guc) +{ + if (guc->execbuf_client) + __guc_client_disable(guc->execbuf_client); +} + +/* + * Set up the memory resources to be shared with the GuC (via the GGTT) + * at firmware loading time. + */ +int intel_guc_submission_init(struct intel_guc *guc) +{ + int ret; + + if (guc->stage_desc_pool) + return 0; + + ret = guc_stage_desc_pool_create(guc); + if (ret) + return ret; + /* + * Keep static analysers happy, let them know that we allocated the + * vma after testing that it didn't exist earlier. + */ + GEM_BUG_ON(!guc->stage_desc_pool); + + WARN_ON(!guc_verify_doorbells(guc)); + ret = guc_clients_create(guc); + if (ret) + goto err_pool; + + return 0; + +err_pool: + guc_stage_desc_pool_destroy(guc); + return ret; +} + +void intel_guc_submission_fini(struct intel_guc *guc) +{ + guc_clients_destroy(guc); + WARN_ON(!guc_verify_doorbells(guc)); + + if (guc->stage_desc_pool) + guc_stage_desc_pool_destroy(guc); +} + +static void guc_interrupts_capture(struct intel_gt *gt) +{ + struct intel_rps *rps = >->i915->gt_pm.rps; + struct intel_uncore *uncore = gt->uncore; + struct intel_engine_cs *engine; + enum intel_engine_id id; + int irqs; + + /* tell all command streamers to forward interrupts (but not vblank) + * to GuC + */ + irqs = _MASKED_BIT_ENABLE(GFX_INTERRUPT_STEERING); + for_each_engine(engine, gt->i915, id) + ENGINE_WRITE(engine, RING_MODE_GEN7, irqs); + + /* route USER_INTERRUPT to Host, all others are sent to GuC. */ + irqs = GT_RENDER_USER_INTERRUPT << GEN8_RCS_IRQ_SHIFT | + GT_RENDER_USER_INTERRUPT << GEN8_BCS_IRQ_SHIFT; + /* These three registers have the same bit definitions */ + intel_uncore_write(uncore, GUC_BCS_RCS_IER, ~irqs); + intel_uncore_write(uncore, GUC_VCS2_VCS1_IER, ~irqs); + intel_uncore_write(uncore, GUC_WD_VECS_IER, ~irqs); + + /* + * The REDIRECT_TO_GUC bit of the PMINTRMSK register directs all + * (unmasked) PM interrupts to the GuC. All other bits of this + * register *disable* generation of a specific interrupt. + * + * 'pm_intrmsk_mbz' indicates bits that are NOT to be set when + * writing to the PM interrupt mask register, i.e. interrupts + * that must not be disabled. + * + * If the GuC is handling these interrupts, then we must not let + * the PM code disable ANY interrupt that the GuC is expecting. + * So for each ENABLED (0) bit in this register, we must SET the + * bit in pm_intrmsk_mbz so that it's left enabled for the GuC. + * GuC needs ARAT expired interrupt unmasked hence it is set in + * pm_intrmsk_mbz. + * + * Here we CLEAR REDIRECT_TO_GUC bit in pm_intrmsk_mbz, which will + * result in the register bit being left SET! + */ + rps->pm_intrmsk_mbz |= ARAT_EXPIRED_INTRMSK; + rps->pm_intrmsk_mbz &= ~GEN8_PMINTR_DISABLE_REDIRECT_TO_GUC; +} + +static void guc_interrupts_release(struct intel_gt *gt) +{ + struct intel_rps *rps = >->i915->gt_pm.rps; + struct intel_uncore *uncore = gt->uncore; + struct intel_engine_cs *engine; + enum intel_engine_id id; + int irqs; + + /* + * tell all command streamers NOT to forward interrupts or vblank + * to GuC. + */ + irqs = _MASKED_FIELD(GFX_FORWARD_VBLANK_MASK, GFX_FORWARD_VBLANK_NEVER); + irqs |= _MASKED_BIT_DISABLE(GFX_INTERRUPT_STEERING); + for_each_engine(engine, gt->i915, id) + ENGINE_WRITE(engine, RING_MODE_GEN7, irqs); + + /* route all GT interrupts to the host */ + intel_uncore_write(uncore, GUC_BCS_RCS_IER, 0); + intel_uncore_write(uncore, GUC_VCS2_VCS1_IER, 0); + intel_uncore_write(uncore, GUC_WD_VECS_IER, 0); + + rps->pm_intrmsk_mbz |= GEN8_PMINTR_DISABLE_REDIRECT_TO_GUC; + rps->pm_intrmsk_mbz &= ~ARAT_EXPIRED_INTRMSK; +} + +static void guc_set_default_submission(struct intel_engine_cs *engine) +{ + /* + * We inherit a bunch of functions from execlists that we'd like + * to keep using: + * + * engine->submit_request = execlists_submit_request; + * engine->cancel_requests = execlists_cancel_requests; + * engine->schedule = execlists_schedule; + * + * But we need to override the actual submission backend in order + * to talk to the GuC. + */ + intel_execlists_set_default_submission(engine); + + engine->execlists.tasklet.func = guc_submission_tasklet; + + /* do not use execlists park/unpark */ + engine->park = engine->unpark = NULL; + + engine->reset.prepare = guc_reset_prepare; + engine->reset.reset = guc_reset; + engine->reset.finish = guc_reset_finish; + + engine->cancel_requests = guc_cancel_requests; + + engine->flags &= ~I915_ENGINE_SUPPORTS_STATS; + engine->flags |= I915_ENGINE_NEEDS_BREADCRUMB_TASKLET; + + /* + * For the breadcrumb irq to work we need the interrupts to stay + * enabled. However, on all platforms on which we'll have support for + * GuC submission we don't allow disabling the interrupts at runtime, so + * we're always safe with the current flow. + */ + GEM_BUG_ON(engine->irq_enable || engine->irq_disable); +} + +int intel_guc_submission_enable(struct intel_guc *guc) +{ + struct intel_gt *gt = guc_to_gt(guc); + struct intel_engine_cs *engine; + enum intel_engine_id id; + int err; + + err = i915_inject_load_error(gt->i915, -ENXIO); + if (err) + return err; + + /* + * We're using GuC work items for submitting work through GuC. Since + * we're coalescing multiple requests from a single context into a + * single work item prior to assigning it to execlist_port, we can + * never have more work items than the total number of ports (for all + * engines). The GuC firmware is controlling the HEAD of work queue, + * and it is guaranteed that it will remove the work item from the + * queue before our request is completed. + */ + BUILD_BUG_ON(ARRAY_SIZE(engine->execlists.inflight) * + sizeof(struct guc_wq_item) * + I915_NUM_ENGINES > GUC_WQ_SIZE); + + GEM_BUG_ON(!guc->execbuf_client); + + err = guc_clients_enable(guc); + if (err) + return err; + + /* Take over from manual control of ELSP (execlists) */ + guc_interrupts_capture(gt); + + for_each_engine(engine, gt->i915, id) { + engine->set_default_submission = guc_set_default_submission; + engine->set_default_submission(engine); + } + + return 0; +} + +void intel_guc_submission_disable(struct intel_guc *guc) +{ + struct intel_gt *gt = guc_to_gt(guc); + + GEM_BUG_ON(gt->awake); /* GT should be parked first */ + + guc_interrupts_release(gt); + guc_clients_disable(guc); +} + +static bool __guc_submission_support(struct intel_guc *guc) +{ + /* XXX: GuC submission is unavailable for now */ + return false; + + if (!intel_guc_is_supported(guc)) + return false; + + return i915_modparams.enable_guc & ENABLE_GUC_SUBMISSION; +} + +void intel_guc_submission_init_early(struct intel_guc *guc) +{ + guc->submission_supported = __guc_submission_support(guc); +} + +#if IS_ENABLED(CONFIG_DRM_I915_SELFTEST) +#include "selftest_guc.c" +#endif |