diff options
Diffstat (limited to 'virt/kvm/arm/vgic/vgic-v2.c')
-rw-r--r-- | virt/kvm/arm/vgic/vgic-v2.c | 514 |
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); +} |