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-rw-r--r--virt/kvm/arm/vgic/vgic-v2.c514
1 files changed, 514 insertions, 0 deletions
diff --git a/virt/kvm/arm/vgic/vgic-v2.c b/virt/kvm/arm/vgic/vgic-v2.c
new file mode 100644
index 000000000..91b14dfac
--- /dev/null
+++ b/virt/kvm/arm/vgic/vgic-v2.c
@@ -0,0 +1,514 @@
+/*
+ * Copyright (C) 2015, 2016 ARM Ltd.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program. If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#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->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);
+
+ 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);
+ }
+
+ spin_unlock(&irq->irq_lock);
+ vgic_put_irq(vcpu->kvm, irq);
+ }
+
+ vgic_cpu->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 GICv2 compatible interrupt controller in DT
+ * @node: pointer to the DT node
+ *
+ * Returns 0 if a GICv2 has been found, 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 = vcpu->arch.vgic_cpu.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.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 = vcpu->arch.vgic_cpu.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);
+}