The GICv4.1 architecture gives the hypervisor the option to let the guest choose whether it wants the good old SGIs with an active state, or the new, HW-based ones that do not have one.
For this, plumb the configuration of SGIs into the GICv3 MMIO handling, present the GICD_TYPER2.nASSGIcap to the guest, and handle the GICD_CTLR.nASSGIreq setting. Signed-off-by: Marc Zyngier <[email protected]> --- virt/kvm/arm/vgic/vgic-mmio-v3.c | 48 ++++++++++++++++++++++++++++++-- 1 file changed, 46 insertions(+), 2 deletions(-) diff --git a/virt/kvm/arm/vgic/vgic-mmio-v3.c b/virt/kvm/arm/vgic/vgic-mmio-v3.c index d73f4ffd7d36..31ff8c7e09b0 100644 --- a/virt/kvm/arm/vgic/vgic-mmio-v3.c +++ b/virt/kvm/arm/vgic/vgic-mmio-v3.c @@ -3,6 +3,7 @@ * VGICv3 MMIO handling functions */ +#include <linux/bitfield.h> #include <linux/irqchip/arm-gic-v3.h> #include <linux/kvm.h> #include <linux/kvm_host.h> @@ -70,6 +71,8 @@ static unsigned long vgic_mmio_read_v3_misc(struct kvm_vcpu *vcpu, if (vgic->enabled) value |= GICD_CTLR_ENABLE_SS_G1; value |= GICD_CTLR_ARE_NS | GICD_CTLR_DS; + if (kvm_vgic_global_state.has_gicv4_1 && vgic->nassgireq) + value |= GICD_CTLR_nASSGIreq; break; case GICD_TYPER: value = vgic->nr_spis + VGIC_NR_PRIVATE_IRQS; @@ -81,6 +84,10 @@ static unsigned long vgic_mmio_read_v3_misc(struct kvm_vcpu *vcpu, value |= (INTERRUPT_ID_BITS_SPIS - 1) << 19; } break; + case GICD_TYPER2: + if (kvm_vgic_global_state.has_gicv4_1) + value = GICD_TYPER2_nASSGIcap; + break; case GICD_IIDR: value = (PRODUCT_ID_KVM << GICD_IIDR_PRODUCT_ID_SHIFT) | (vgic->implementation_rev << GICD_IIDR_REVISION_SHIFT) | @@ -98,17 +105,43 @@ static void vgic_mmio_write_v3_misc(struct kvm_vcpu *vcpu, unsigned long val) { struct vgic_dist *dist = &vcpu->kvm->arch.vgic; - bool was_enabled = dist->enabled; switch (addr & 0x0c) { - case GICD_CTLR: + case GICD_CTLR: { + bool was_enabled, is_hwsgi; + + mutex_lock(&vcpu->kvm->lock); + + was_enabled = dist->enabled; + is_hwsgi = dist->nassgireq; + dist->enabled = val & GICD_CTLR_ENABLE_SS_G1; + /* Not a GICv4.1? No HW SGIs */ + if (!kvm_vgic_global_state.has_gicv4_1) + val &= ~GICD_CTLR_nASSGIreq; + + /* Dist stays enabled? nASSGIreq is RO */ + if (was_enabled && dist->enabled) { + val &= ~GICD_CTLR_nASSGIreq; + val |= FIELD_PREP(GICD_CTLR_nASSGIreq, is_hwsgi); + } + + /* Switching HW SGIs? */ + dist->nassgireq = val & GICD_CTLR_nASSGIreq; + if (is_hwsgi != dist->nassgireq) + vgic_v4_configure_vsgis(vcpu->kvm); + if (!was_enabled && dist->enabled) vgic_kick_vcpus(vcpu->kvm); + + mutex_unlock(&vcpu->kvm->lock); break; + } case GICD_TYPER: + case GICD_TYPER2: case GICD_IIDR: + /* This is at best for documentation purposes... */ return; } } @@ -117,10 +150,21 @@ static int vgic_mmio_uaccess_write_v3_misc(struct kvm_vcpu *vcpu, gpa_t addr, unsigned int len, unsigned long val) { + struct vgic_dist *dist = &vcpu->kvm->arch.vgic; + switch (addr & 0x0c) { case GICD_IIDR: if (val != vgic_mmio_read_v3_misc(vcpu, addr, len)) return -EINVAL; + return 0; + case GICD_CTLR: + /* Not a GICv4.1? No HW SGIs */ + if (!kvm_vgic_global_state.has_gicv4_1) + val &= ~GICD_CTLR_nASSGIreq; + + dist->enabled = val & GICD_CTLR_ENABLE_SS_G1; + dist->nassgireq = val & GICD_CTLR_nASSGIreq; + return 0; } vgic_mmio_write_v3_misc(vcpu, addr, len, val); -- 2.20.1 _______________________________________________ kvmarm mailing list [email protected] https://lists.cs.columbia.edu/mailman/listinfo/kvmarm
