From: Marc Zyngier <marc.zyng...@arm.com>
Those three registers are v2 emulation specific, so their implementation
lives entirely in vgic-mmio-v2.c. Also they are handled in one function,
as their implementation is pretty simple.
When the guest enables the distributor, we kick all VCPUs to get
potentially pending interrupts serviced.
Signed-off-by: Marc Zyngier <marc.zyng...@arm.com>
Signed-off-by: Andre Przywara <andre.przyw...@arm.com>
---
Changelog RFC..v1:
- kick VCPUs is the distributor gets enabled
- improve comment
Changelog v1 .. v2:
- adapt to new MMIO framework
- use switch() statements to improve readability
Changelog v2 .. v3:
- add vgic_kick_vcpus() implementation
include/linux/irqchip/arm-gic.h | 1 +
virt/kvm/arm/vgic/vgic-mmio-v2.c | 48 +++++++++++++++++++++++++++++++++++++++-
virt/kvm/arm/vgic/vgic.c | 15 +++++++++++++
virt/kvm/arm/vgic/vgic.h | 4 ++++
4 files changed, 67 insertions(+), 1 deletion(-)
diff --git a/include/linux/irqchip/arm-gic.h b/include/linux/irqchip/arm-gic.h
index be0d26f..fd05185 100644
--- a/include/linux/irqchip/arm-gic.h
+++ b/include/linux/irqchip/arm-gic.h
@@ -33,6 +33,7 @@
#define GIC_DIST_CTRL 0x000
#define GIC_DIST_CTR 0x004
+#define GIC_DIST_IIDR 0x008
#define GIC_DIST_IGROUP 0x080
#define GIC_DIST_ENABLE_SET 0x100
#define GIC_DIST_ENABLE_CLEAR 0x180
diff --git a/virt/kvm/arm/vgic/vgic-mmio-v2.c b/virt/kvm/arm/vgic/vgic-mmio-v2.c
index 2729a22..69e96f7 100644
--- a/virt/kvm/arm/vgic/vgic-mmio-v2.c
+++ b/virt/kvm/arm/vgic/vgic-mmio-v2.c
@@ -20,9 +20,55 @@
#include "vgic.h"
#include "vgic-mmio.h"
+static unsigned long vgic_mmio_read_v2_misc(struct kvm_vcpu *vcpu,
+ gpa_t addr, unsigned int len)
+{
+ u32 value;
+
+ switch (addr & 0x0c) {
+ case GIC_DIST_CTRL:
+ value = vcpu->kvm->arch.vgic.enabled ? GICD_ENABLE : 0;
+ break;
+ case GIC_DIST_CTR:
+ value = vcpu->kvm->arch.vgic.nr_spis + VGIC_NR_PRIVATE_IRQS;
+ value = (value >> 5) - 1;
+ value |= (atomic_read(&vcpu->kvm->online_vcpus) - 1) << 5;
+ break;
+ case GIC_DIST_IIDR:
+ value = (PRODUCT_ID_KVM << 24) | (IMPLEMENTER_ARM << 0);
+ break;
+ default:
+ return 0;
+ }
+
+ return extract_bytes(value, addr & 3, len);
+}
+
+static void vgic_mmio_write_v2_misc(struct kvm_vcpu *vcpu,
+ gpa_t addr, unsigned int len,
+ unsigned long val)
+{
+ switch (addr & 0x0c) {
+ case GIC_DIST_CTRL:
+ if (!(addr & 1)) {
+ struct vgic_dist *dist = &vcpu->kvm->arch.vgic;
+ bool was_enabled = dist->enabled;
+
+ dist->enabled = val & GICD_ENABLE;
+ if (!was_enabled && dist->enabled)
+ vgic_kick_vcpus(vcpu->kvm);
+ }
+ break;
+ case GIC_DIST_CTR:
+ case GIC_DIST_IIDR:
+ /* Nothing to do */
+ return;
+ }
+}
+
static const struct vgic_register_region vgic_v2_dist_registers[] = {
REGISTER_DESC_WITH_LENGTH(GIC_DIST_CTRL,
- vgic_mmio_read_raz, vgic_mmio_write_wi, 12),
+ vgic_mmio_read_v2_misc, vgic_mmio_write_v2_misc, 12),
REGISTER_DESC_WITH_BITS_PER_IRQ(GIC_DIST_IGROUP,
vgic_mmio_read_rao, vgic_mmio_write_wi, 1),
REGISTER_DESC_WITH_BITS_PER_IRQ(GIC_DIST_ENABLE_SET,
diff --git a/virt/kvm/arm/vgic/vgic.c b/virt/kvm/arm/vgic/vgic.c
index c3dbcf3..5355de6 100644
--- a/virt/kvm/arm/vgic/vgic.c
+++ b/virt/kvm/arm/vgic/vgic.c
@@ -544,3 +544,18 @@ int kvm_vgic_vcpu_pending_irq(struct kvm_vcpu *vcpu)
return pending;
}
+
+void vgic_kick_vcpus(struct kvm *kvm)
+{
+ struct kvm_vcpu *vcpu;
+ int c;
+
+ /*
+ * We've injected an interrupt, time to find out who deserves
+ * a good kick...
+ */
+ kvm_for_each_vcpu(c, vcpu, kvm) {
+ if (kvm_vgic_vcpu_pending_irq(vcpu))
+ kvm_vcpu_kick(vcpu);
+ }
+}
diff --git a/virt/kvm/arm/vgic/vgic.h b/virt/kvm/arm/vgic/vgic.h
index fd9acaa..cf62015 100644
--- a/virt/kvm/arm/vgic/vgic.h
+++ b/virt/kvm/arm/vgic/vgic.h
@@ -16,11 +16,15 @@
#ifndef __KVM_ARM_VGIC_NEW_H__
#define __KVM_ARM_VGIC_NEW_H__
+#define PRODUCT_ID_KVM 0x4b /* ASCII code K */
+#define IMPLEMENTER_ARM 0x43b
+
#define vgic_irq_is_sgi(intid) ((intid) < VGIC_NR_SGIS)
struct vgic_irq *vgic_get_irq(struct kvm *kvm, struct kvm_vcpu *vcpu,
u32 intid);
bool vgic_queue_irq_unlock(struct kvm *kvm, struct vgic_irq *irq);
+void vgic_kick_vcpus(struct kvm *kvm);
void vgic_v2_process_maintenance(struct kvm_vcpu *vcpu);
void vgic_v2_fold_lr_state(struct kvm_vcpu *vcpu);
--
2.7.3
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