1 files changed, 504 insertions, 0 deletions

diff --git a/arch/arm64/kvm/vgic/vgic-v2.c b/arch/arm64/kvm/vgic/vgic-v2.c
new file mode 100644
index 000000000000..ebf53a4e1296
--- /dev/null
+++ b/arch/arm64/kvm/vgic/vgic-v2.c
@@ -0,0 +1,504 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Copyright (C) 2015, 2016 ARM Ltd.
+ */
+
+#include <linux/irqchip/arm-gic.h>
+#include <linux/kvm.h>
+#include <linux/kvm_host.h>
+#include <kvm/arm_vgic.h>
+#include <asm/kvm_mmu.h>
+
+#include "vgic.h"
+
+static inline void vgic_v2_write_lr(int lr, u32 val)
+{
+	void __iomem *base = kvm_vgic_global_state.vctrl_base;
+
+	writel_relaxed(val, base + GICH_LR0 + (lr * 4));
+}
+
+void vgic_v2_init_lrs(void)
+{
+	int i;
+
+	for (i = 0; i < kvm_vgic_global_state.nr_lr; i++)
+		vgic_v2_write_lr(i, 0);
+}
+
+void vgic_v2_set_underflow(struct kvm_vcpu *vcpu)
+{
+	struct vgic_v2_cpu_if *cpuif = &vcpu->arch.vgic_cpu.vgic_v2;
+
+	cpuif->vgic_hcr |= GICH_HCR_UIE;
+}
+
+static bool lr_signals_eoi_mi(u32 lr_val)
+{
+	return !(lr_val & GICH_LR_STATE) && (lr_val & GICH_LR_EOI) &&
+	       !(lr_val & GICH_LR_HW);
+}
+
+/*
+ * transfer the content of the LRs back into the corresponding ap_list:
+ * - active bit is transferred as is
+ * - pending bit is
+ *   - transferred as is in case of edge sensitive IRQs
+ *   - set to the line-level (resample time) for level sensitive IRQs
+ */
+void vgic_v2_fold_lr_state(struct kvm_vcpu *vcpu)
+{
+	struct vgic_cpu *vgic_cpu = &vcpu->arch.vgic_cpu;
+	struct vgic_v2_cpu_if *cpuif = &vgic_cpu->vgic_v2;
+	int lr;
+
+	DEBUG_SPINLOCK_BUG_ON(!irqs_disabled());
+
+	cpuif->vgic_hcr &= ~GICH_HCR_UIE;
+
+	for (lr = 0; lr < vgic_cpu->vgic_v2.used_lrs; lr++) {
+		u32 val = cpuif->vgic_lr[lr];
+		u32 cpuid, intid = val & GICH_LR_VIRTUALID;
+		struct vgic_irq *irq;
+
+		/* Extract the source vCPU id from the LR */
+		cpuid = val & GICH_LR_PHYSID_CPUID;
+		cpuid >>= GICH_LR_PHYSID_CPUID_SHIFT;
+		cpuid &= 7;
+
+		/* Notify fds when the guest EOI'ed a level-triggered SPI */
+		if (lr_signals_eoi_mi(val) && vgic_valid_spi(vcpu->kvm, intid))
+			kvm_notify_acked_irq(vcpu->kvm, 0,
+					     intid - VGIC_NR_PRIVATE_IRQS);
+
+		irq = vgic_get_irq(vcpu->kvm, vcpu, intid);
+
+		raw_spin_lock(&irq->irq_lock);
+
+		/* Always preserve the active bit */
+		irq->active = !!(val & GICH_LR_ACTIVE_BIT);
+
+		if (irq->active && vgic_irq_is_sgi(intid))
+			irq->active_source = cpuid;
+
+		/* Edge is the only case where we preserve the pending bit */
+		if (irq->config == VGIC_CONFIG_EDGE &&
+		    (val & GICH_LR_PENDING_BIT)) {
+			irq->pending_latch = true;
+
+			if (vgic_irq_is_sgi(intid))
+				irq->source |= (1 << cpuid);
+		}
+
+		/*
+		 * Clear soft pending state when level irqs have been acked.
+		 */
+		if (irq->config == VGIC_CONFIG_LEVEL && !(val & GICH_LR_STATE))
+			irq->pending_latch = false;
+
+		/*
+		 * Level-triggered mapped IRQs are special because we only
+		 * observe rising edges as input to the VGIC.
+		 *
+		 * If the guest never acked the interrupt we have to sample
+		 * the physical line and set the line level, because the
+		 * device state could have changed or we simply need to
+		 * process the still pending interrupt later.
+		 *
+		 * If this causes us to lower the level, we have to also clear
+		 * the physical active state, since we will otherwise never be
+		 * told when the interrupt becomes asserted again.
+		 */
+		if (vgic_irq_is_mapped_level(irq) && (val & GICH_LR_PENDING_BIT)) {
+			irq->line_level = vgic_get_phys_line_level(irq);
+
+			if (!irq->line_level)
+				vgic_irq_set_phys_active(irq, false);
+		}
+
+		raw_spin_unlock(&irq->irq_lock);
+		vgic_put_irq(vcpu->kvm, irq);
+	}
+
+	cpuif->used_lrs = 0;
+}
+
+/*
+ * Populates the particular LR with the state of a given IRQ:
+ * - for an edge sensitive IRQ the pending state is cleared in struct vgic_irq
+ * - for a level sensitive IRQ the pending state value is unchanged;
+ *   it is dictated directly by the input level
+ *
+ * If @irq describes an SGI with multiple sources, we choose the
+ * lowest-numbered source VCPU and clear that bit in the source bitmap.
+ *
+ * The irq_lock must be held by the caller.
+ */
+void vgic_v2_populate_lr(struct kvm_vcpu *vcpu, struct vgic_irq *irq, int lr)
+{
+	u32 val = irq->intid;
+	bool allow_pending = true;
+
+	if (irq->active) {
+		val |= GICH_LR_ACTIVE_BIT;
+		if (vgic_irq_is_sgi(irq->intid))
+			val |= irq->active_source << GICH_LR_PHYSID_CPUID_SHIFT;
+		if (vgic_irq_is_multi_sgi(irq)) {
+			allow_pending = false;
+			val |= GICH_LR_EOI;
+		}
+	}
+
+	if (irq->group)
+		val |= GICH_LR_GROUP1;
+
+	if (irq->hw) {
+		val |= GICH_LR_HW;
+		val |= irq->hwintid << GICH_LR_PHYSID_CPUID_SHIFT;
+		/*
+		 * Never set pending+active on a HW interrupt, as the
+		 * pending state is kept at the physical distributor
+		 * level.
+		 */
+		if (irq->active)
+			allow_pending = false;
+	} else {
+		if (irq->config == VGIC_CONFIG_LEVEL) {
+			val |= GICH_LR_EOI;
+
+			/*
+			 * Software resampling doesn't work very well
+			 * if we allow P+A, so let's not do that.
+			 */
+			if (irq->active)
+				allow_pending = false;
+		}
+	}
+
+	if (allow_pending && irq_is_pending(irq)) {
+		val |= GICH_LR_PENDING_BIT;
+
+		if (irq->config == VGIC_CONFIG_EDGE)
+			irq->pending_latch = false;
+
+		if (vgic_irq_is_sgi(irq->intid)) {
+			u32 src = ffs(irq->source);
+
+			if (WARN_RATELIMIT(!src, "No SGI source for INTID %d\n",
+					   irq->intid))
+				return;
+
+			val |= (src - 1) << GICH_LR_PHYSID_CPUID_SHIFT;
+			irq->source &= ~(1 << (src - 1));
+			if (irq->source) {
+				irq->pending_latch = true;
+				val |= GICH_LR_EOI;
+			}
+		}
+	}
+
+	/*
+	 * Level-triggered mapped IRQs are special because we only observe
+	 * rising edges as input to the VGIC.  We therefore lower the line
+	 * level here, so that we can take new virtual IRQs.  See
+	 * vgic_v2_fold_lr_state for more info.
+	 */
+	if (vgic_irq_is_mapped_level(irq) && (val & GICH_LR_PENDING_BIT))
+		irq->line_level = false;
+
+	/* The GICv2 LR only holds five bits of priority. */
+	val |= (irq->priority >> 3) << GICH_LR_PRIORITY_SHIFT;
+
+	vcpu->arch.vgic_cpu.vgic_v2.vgic_lr[lr] = val;
+}
+
+void vgic_v2_clear_lr(struct kvm_vcpu *vcpu, int lr)
+{
+	vcpu->arch.vgic_cpu.vgic_v2.vgic_lr[lr] = 0;
+}
+
+void vgic_v2_set_vmcr(struct kvm_vcpu *vcpu, struct vgic_vmcr *vmcrp)
+{
+	struct vgic_v2_cpu_if *cpu_if = &vcpu->arch.vgic_cpu.vgic_v2;
+	u32 vmcr;
+
+	vmcr = (vmcrp->grpen0 << GICH_VMCR_ENABLE_GRP0_SHIFT) &
+		GICH_VMCR_ENABLE_GRP0_MASK;
+	vmcr |= (vmcrp->grpen1 << GICH_VMCR_ENABLE_GRP1_SHIFT) &
+		GICH_VMCR_ENABLE_GRP1_MASK;
+	vmcr |= (vmcrp->ackctl << GICH_VMCR_ACK_CTL_SHIFT) &
+		GICH_VMCR_ACK_CTL_MASK;
+	vmcr |= (vmcrp->fiqen << GICH_VMCR_FIQ_EN_SHIFT) &
+		GICH_VMCR_FIQ_EN_MASK;
+	vmcr |= (vmcrp->cbpr << GICH_VMCR_CBPR_SHIFT) &
+		GICH_VMCR_CBPR_MASK;
+	vmcr |= (vmcrp->eoim << GICH_VMCR_EOI_MODE_SHIFT) &
+		GICH_VMCR_EOI_MODE_MASK;
+	vmcr |= (vmcrp->abpr << GICH_VMCR_ALIAS_BINPOINT_SHIFT) &
+		GICH_VMCR_ALIAS_BINPOINT_MASK;
+	vmcr |= (vmcrp->bpr << GICH_VMCR_BINPOINT_SHIFT) &
+		GICH_VMCR_BINPOINT_MASK;
+	vmcr |= ((vmcrp->pmr >> GICV_PMR_PRIORITY_SHIFT) <<
+		 GICH_VMCR_PRIMASK_SHIFT) & GICH_VMCR_PRIMASK_MASK;
+
+	cpu_if->vgic_vmcr = vmcr;
+}
+
+void vgic_v2_get_vmcr(struct kvm_vcpu *vcpu, struct vgic_vmcr *vmcrp)
+{
+	struct vgic_v2_cpu_if *cpu_if = &vcpu->arch.vgic_cpu.vgic_v2;
+	u32 vmcr;
+
+	vmcr = cpu_if->vgic_vmcr;
+
+	vmcrp->grpen0 = (vmcr & GICH_VMCR_ENABLE_GRP0_MASK) >>
+		GICH_VMCR_ENABLE_GRP0_SHIFT;
+	vmcrp->grpen1 = (vmcr & GICH_VMCR_ENABLE_GRP1_MASK) >>
+		GICH_VMCR_ENABLE_GRP1_SHIFT;
+	vmcrp->ackctl = (vmcr & GICH_VMCR_ACK_CTL_MASK) >>
+		GICH_VMCR_ACK_CTL_SHIFT;
+	vmcrp->fiqen = (vmcr & GICH_VMCR_FIQ_EN_MASK) >>
+		GICH_VMCR_FIQ_EN_SHIFT;
+	vmcrp->cbpr = (vmcr & GICH_VMCR_CBPR_MASK) >>
+		GICH_VMCR_CBPR_SHIFT;
+	vmcrp->eoim = (vmcr & GICH_VMCR_EOI_MODE_MASK) >>
+		GICH_VMCR_EOI_MODE_SHIFT;
+
+	vmcrp->abpr = (vmcr & GICH_VMCR_ALIAS_BINPOINT_MASK) >>
+			GICH_VMCR_ALIAS_BINPOINT_SHIFT;
+	vmcrp->bpr  = (vmcr & GICH_VMCR_BINPOINT_MASK) >>
+			GICH_VMCR_BINPOINT_SHIFT;
+	vmcrp->pmr  = ((vmcr & GICH_VMCR_PRIMASK_MASK) >>
+			GICH_VMCR_PRIMASK_SHIFT) << GICV_PMR_PRIORITY_SHIFT;
+}
+
+void vgic_v2_enable(struct kvm_vcpu *vcpu)
+{
+	/*
+	 * By forcing VMCR to zero, the GIC will restore the binary
+	 * points to their reset values. Anything else resets to zero
+	 * anyway.
+	 */
+	vcpu->arch.vgic_cpu.vgic_v2.vgic_vmcr = 0;
+
+	/* Get the show on the road... */
+	vcpu->arch.vgic_cpu.vgic_v2.vgic_hcr = GICH_HCR_EN;
+}
+
+/* check for overlapping regions and for regions crossing the end of memory */
+static bool vgic_v2_check_base(gpa_t dist_base, gpa_t cpu_base)
+{
+	if (dist_base + KVM_VGIC_V2_DIST_SIZE < dist_base)
+		return false;
+	if (cpu_base + KVM_VGIC_V2_CPU_SIZE < cpu_base)
+		return false;
+
+	if (dist_base + KVM_VGIC_V2_DIST_SIZE <= cpu_base)
+		return true;
+	if (cpu_base + KVM_VGIC_V2_CPU_SIZE <= dist_base)
+		return true;
+
+	return false;
+}
+
+int vgic_v2_map_resources(struct kvm *kvm)
+{
+	struct vgic_dist *dist = &kvm->arch.vgic;
+	int ret = 0;
+
+	if (vgic_ready(kvm))
+		goto out;
+
+	if (IS_VGIC_ADDR_UNDEF(dist->vgic_dist_base) ||
+	    IS_VGIC_ADDR_UNDEF(dist->vgic_cpu_base)) {
+		kvm_err("Need to set vgic cpu and dist addresses first\n");
+		ret = -ENXIO;
+		goto out;
+	}
+
+	if (!vgic_v2_check_base(dist->vgic_dist_base, dist->vgic_cpu_base)) {
+		kvm_err("VGIC CPU and dist frames overlap\n");
+		ret = -EINVAL;
+		goto out;
+	}
+
+	/*
+	 * Initialize the vgic if this hasn't already been done on demand by
+	 * accessing the vgic state from userspace.
+	 */
+	ret = vgic_init(kvm);
+	if (ret) {
+		kvm_err("Unable to initialize VGIC dynamic data structures\n");
+		goto out;
+	}
+
+	ret = vgic_register_dist_iodev(kvm, dist->vgic_dist_base, VGIC_V2);
+	if (ret) {
+		kvm_err("Unable to register VGIC MMIO regions\n");
+		goto out;
+	}
+
+	if (!static_branch_unlikely(&vgic_v2_cpuif_trap)) {
+		ret = kvm_phys_addr_ioremap(kvm, dist->vgic_cpu_base,
+					    kvm_vgic_global_state.vcpu_base,
+					    KVM_VGIC_V2_CPU_SIZE, true);
+		if (ret) {
+			kvm_err("Unable to remap VGIC CPU to VCPU\n");
+			goto out;
+		}
+	}
+
+	dist->ready = true;
+
+out:
+	return ret;
+}
+
+DEFINE_STATIC_KEY_FALSE(vgic_v2_cpuif_trap);
+
+/**
+ * vgic_v2_probe - probe for a VGICv2 compatible interrupt controller
+ * @info:	pointer to the GIC description
+ *
+ * Returns 0 if the VGICv2 has been probed successfully, returns an error code
+ * otherwise
+ */
+int vgic_v2_probe(const struct gic_kvm_info *info)
+{
+	int ret;
+	u32 vtr;
+
+	if (!info->vctrl.start) {
+		kvm_err("GICH not present in the firmware table\n");
+		return -ENXIO;
+	}
+
+	if (!PAGE_ALIGNED(info->vcpu.start) ||
+	    !PAGE_ALIGNED(resource_size(&info->vcpu))) {
+		kvm_info("GICV region size/alignment is unsafe, using trapping (reduced performance)\n");
+
+		ret = create_hyp_io_mappings(info->vcpu.start,
+					     resource_size(&info->vcpu),
+					     &kvm_vgic_global_state.vcpu_base_va,
+					     &kvm_vgic_global_state.vcpu_hyp_va);
+		if (ret) {
+			kvm_err("Cannot map GICV into hyp\n");
+			goto out;
+		}
+
+		static_branch_enable(&vgic_v2_cpuif_trap);
+	}
+
+	ret = create_hyp_io_mappings(info->vctrl.start,
+				     resource_size(&info->vctrl),
+				     &kvm_vgic_global_state.vctrl_base,
+				     &kvm_vgic_global_state.vctrl_hyp);
+	if (ret) {
+		kvm_err("Cannot map VCTRL into hyp\n");
+		goto out;
+	}
+
+	vtr = readl_relaxed(kvm_vgic_global_state.vctrl_base + GICH_VTR);
+	kvm_vgic_global_state.nr_lr = (vtr & 0x3f) + 1;
+
+	ret = kvm_register_vgic_device(KVM_DEV_TYPE_ARM_VGIC_V2);
+	if (ret) {
+		kvm_err("Cannot register GICv2 KVM device\n");
+		goto out;
+	}
+
+	kvm_vgic_global_state.can_emulate_gicv2 = true;
+	kvm_vgic_global_state.vcpu_base = info->vcpu.start;
+	kvm_vgic_global_state.type = VGIC_V2;
+	kvm_vgic_global_state.max_gic_vcpus = VGIC_V2_MAX_CPUS;
+
+	kvm_debug("vgic-v2@%llx\n", info->vctrl.start);
+
+	return 0;
+out:
+	if (kvm_vgic_global_state.vctrl_base)
+		iounmap(kvm_vgic_global_state.vctrl_base);
+	if (kvm_vgic_global_state.vcpu_base_va)
+		iounmap(kvm_vgic_global_state.vcpu_base_va);
+
+	return ret;
+}
+
+static void save_lrs(struct kvm_vcpu *vcpu, void __iomem *base)
+{
+	struct vgic_v2_cpu_if *cpu_if = &vcpu->arch.vgic_cpu.vgic_v2;
+	u64 used_lrs = cpu_if->used_lrs;
+	u64 elrsr;
+	int i;
+
+	elrsr = readl_relaxed(base + GICH_ELRSR0);
+	if (unlikely(used_lrs > 32))
+		elrsr |= ((u64)readl_relaxed(base + GICH_ELRSR1)) << 32;
+
+	for (i = 0; i < used_lrs; i++) {
+		if (elrsr & (1UL << i))
+			cpu_if->vgic_lr[i] &= ~GICH_LR_STATE;
+		else
+			cpu_if->vgic_lr[i] = readl_relaxed(base + GICH_LR0 + (i * 4));
+
+		writel_relaxed(0, base + GICH_LR0 + (i * 4));
+	}
+}
+
+void vgic_v2_save_state(struct kvm_vcpu *vcpu)
+{
+	void __iomem *base = kvm_vgic_global_state.vctrl_base;
+	u64 used_lrs = vcpu->arch.vgic_cpu.vgic_v2.used_lrs;
+
+	if (!base)
+		return;
+
+	if (used_lrs) {
+		save_lrs(vcpu, base);
+		writel_relaxed(0, base + GICH_HCR);
+	}
+}
+
+void vgic_v2_restore_state(struct kvm_vcpu *vcpu)
+{
+	struct vgic_v2_cpu_if *cpu_if = &vcpu->arch.vgic_cpu.vgic_v2;
+	void __iomem *base = kvm_vgic_global_state.vctrl_base;
+	u64 used_lrs = cpu_if->used_lrs;
+	int i;
+
+	if (!base)
+		return;
+
+	if (used_lrs) {
+		writel_relaxed(cpu_if->vgic_hcr, base + GICH_HCR);
+		for (i = 0; i < used_lrs; i++) {
+			writel_relaxed(cpu_if->vgic_lr[i],
+				       base + GICH_LR0 + (i * 4));
+		}
+	}
+}
+
+void vgic_v2_load(struct kvm_vcpu *vcpu)
+{
+	struct vgic_v2_cpu_if *cpu_if = &vcpu->arch.vgic_cpu.vgic_v2;
+
+	writel_relaxed(cpu_if->vgic_vmcr,
+		       kvm_vgic_global_state.vctrl_base + GICH_VMCR);
+	writel_relaxed(cpu_if->vgic_apr,
+		       kvm_vgic_global_state.vctrl_base + GICH_APR);
+}
+
+void vgic_v2_vmcr_sync(struct kvm_vcpu *vcpu)
+{
+	struct vgic_v2_cpu_if *cpu_if = &vcpu->arch.vgic_cpu.vgic_v2;
+
+	cpu_if->vgic_vmcr = readl_relaxed(kvm_vgic_global_state.vctrl_base + GICH_VMCR);
+}
+
+void vgic_v2_put(struct kvm_vcpu *vcpu)
+{
+	struct vgic_v2_cpu_if *cpu_if = &vcpu->arch.vgic_cpu.vgic_v2;
+
+	vgic_v2_vmcr_sync(vcpu);
+	cpu_if->vgic_apr = readl_relaxed(kvm_vgic_global_state.vctrl_base + GICH_APR);
+}