diff options
| -rw-r--r-- | Documentation/virtual/kvm/devices/arm-vgic.txt | 6 | ||||
| -rw-r--r-- | include/linux/irqchip/arm-gic.h | 3 | ||||
| -rw-r--r-- | virt/kvm/arm/vgic/vgic-mmio-v2.c | 20 | ||||
| -rw-r--r-- | virt/kvm/arm/vgic/vgic-v2.c | 8 | ||||
| -rw-r--r-- | virt/kvm/arm/vgic/vgic.h | 9 |
5 files changed, 39 insertions, 7 deletions
diff --git a/Documentation/virtual/kvm/devices/arm-vgic.txt b/Documentation/virtual/kvm/devices/arm-vgic.txt index 76e61c883347..b2f60ca8b60c 100644 --- a/Documentation/virtual/kvm/devices/arm-vgic.txt +++ b/Documentation/virtual/kvm/devices/arm-vgic.txt @@ -83,6 +83,12 @@ Groups: Bits for undefined preemption levels are RAZ/WI. + For historical reasons and to provide ABI compatibility with userspace we + export the GICC_PMR register in the format of the GICH_VMCR.VMPriMask + field in the lower 5 bits of a word, meaning that userspace must always + use the lower 5 bits to communicate with the KVM device and must shift the + value left by 3 places to obtain the actual priority mask level. + Limitations: - Priorities are not implemented, and registers are RAZ/WI - Currently only implemented for KVM_DEV_TYPE_ARM_VGIC_V2. diff --git a/include/linux/irqchip/arm-gic.h b/include/linux/irqchip/arm-gic.h index eafc965b3eb8..dc30f3d057eb 100644 --- a/include/linux/irqchip/arm-gic.h +++ b/include/linux/irqchip/arm-gic.h @@ -96,6 +96,9 @@ #define GICH_MISR_EOI (1 << 0) #define GICH_MISR_U (1 << 1) +#define GICV_PMR_PRIORITY_SHIFT 3 +#define GICV_PMR_PRIORITY_MASK (0x1f << GICV_PMR_PRIORITY_SHIFT) + #ifndef __ASSEMBLY__ #include <linux/irqdomain.h> diff --git a/virt/kvm/arm/vgic/vgic-mmio-v2.c b/virt/kvm/arm/vgic/vgic-mmio-v2.c index a3ad7ff95c9b..0a4283ed9aa7 100644 --- a/virt/kvm/arm/vgic/vgic-mmio-v2.c +++ b/virt/kvm/arm/vgic/vgic-mmio-v2.c @@ -229,7 +229,15 @@ static unsigned long vgic_mmio_read_vcpuif(struct kvm_vcpu *vcpu, val = vmcr.ctlr; break; case GIC_CPU_PRIMASK: - val = vmcr.pmr; + /* + * Our KVM_DEV_TYPE_ARM_VGIC_V2 device ABI exports the + * the PMR field as GICH_VMCR.VMPriMask rather than + * GICC_PMR.Priority, so we expose the upper five bits of + * priority mask to userspace using the lower bits in the + * unsigned long. + */ + val = (vmcr.pmr & GICV_PMR_PRIORITY_MASK) >> + GICV_PMR_PRIORITY_SHIFT; break; case GIC_CPU_BINPOINT: val = vmcr.bpr; @@ -262,7 +270,15 @@ static void vgic_mmio_write_vcpuif(struct kvm_vcpu *vcpu, vmcr.ctlr = val; break; case GIC_CPU_PRIMASK: - vmcr.pmr = val; + /* + * Our KVM_DEV_TYPE_ARM_VGIC_V2 device ABI exports the + * the PMR field as GICH_VMCR.VMPriMask rather than + * GICC_PMR.Priority, so we expose the upper five bits of + * priority mask to userspace using the lower bits in the + * unsigned long. + */ + vmcr.pmr = (val << GICV_PMR_PRIORITY_SHIFT) & + GICV_PMR_PRIORITY_MASK; break; case GIC_CPU_BINPOINT: vmcr.bpr = val; diff --git a/virt/kvm/arm/vgic/vgic-v2.c b/virt/kvm/arm/vgic/vgic-v2.c index 94cf4b9b6471..b637d9c7afe3 100644 --- a/virt/kvm/arm/vgic/vgic-v2.c +++ b/virt/kvm/arm/vgic/vgic-v2.c @@ -206,8 +206,8 @@ void vgic_v2_set_vmcr(struct kvm_vcpu *vcpu, struct vgic_vmcr *vmcrp) GICH_VMCR_ALIAS_BINPOINT_MASK; vmcr |= (vmcrp->bpr << GICH_VMCR_BINPOINT_SHIFT) & GICH_VMCR_BINPOINT_MASK; - vmcr |= (vmcrp->pmr << GICH_VMCR_PRIMASK_SHIFT) & - GICH_VMCR_PRIMASK_MASK; + vmcr |= ((vmcrp->pmr >> GICV_PMR_PRIORITY_SHIFT) << + GICH_VMCR_PRIMASK_SHIFT) & GICH_VMCR_PRIMASK_MASK; vcpu->arch.vgic_cpu.vgic_v2.vgic_vmcr = vmcr; } @@ -222,8 +222,8 @@ void vgic_v2_get_vmcr(struct kvm_vcpu *vcpu, struct vgic_vmcr *vmcrp) 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; + vmcrp->pmr = ((vmcr & GICH_VMCR_PRIMASK_MASK) >> + GICH_VMCR_PRIMASK_SHIFT) << GICV_PMR_PRIORITY_SHIFT; } void vgic_v2_enable(struct kvm_vcpu *vcpu) diff --git a/virt/kvm/arm/vgic/vgic.h b/virt/kvm/arm/vgic/vgic.h index 91566f5aac9b..6cf557e9f718 100644 --- a/virt/kvm/arm/vgic/vgic.h +++ b/virt/kvm/arm/vgic/vgic.h @@ -81,11 +81,18 @@ static inline bool irq_is_pending(struct vgic_irq *irq) return irq->pending_latch || irq->line_level; } +/* + * This struct provides an intermediate representation of the fields contained + * in the GICH_VMCR and ICH_VMCR registers, such that code exporting the GIC + * state to userspace can generate either GICv2 or GICv3 CPU interface + * registers regardless of the hardware backed GIC used. + */ struct vgic_vmcr { u32 ctlr; u32 abpr; u32 bpr; - u32 pmr; + u32 pmr; /* Priority mask field in the GICC_PMR and + * ICC_PMR_EL1 priority field format */ /* Below member variable are valid only for GICv3 */ u32 grpen0; u32 grpen1; |