Re: [RFC PATCH 24/45] KVM: arm/arm64: vgic-new: Add GICv3 CTLR, IIDR, TYPER handlers

Christoffer Dall
2016-03-31T11:53:19Z

On Fri, Mar 25, 2016 at 02:04:47AM +0000, Andre Przywara wrote:
> As in the GICv2 emulation we handle those three registers in one
> function.
>
> Signed-off-by: Andre Przywara <andre.przywara@arm.com>
> ---
> virt/kvm/arm/vgic/vgic.h | 2 ++
> virt/kvm/arm/vgic/vgic_mmio.c | 38 ++++++++++++++++++++++++++++++++++++--
> 2 files changed, 38 insertions(+), 2 deletions(-)
>
> diff --git a/virt/kvm/arm/vgic/vgic.h b/virt/kvm/arm/vgic/vgic.h
> index 4b8952a..0db1abe 100644
> --- a/virt/kvm/arm/vgic/vgic.h
> +++ b/virt/kvm/arm/vgic/vgic.h
> @@ -19,6 +19,8 @@
> #define PRODUCT_ID_KVM 0x4b /* ASCII code K */
> #define IMPLEMENTER_ARM 0x43b
>
> +#define INTERRUPT_ID_BITS_SPIS 10
> +
> struct vgic_irq *vgic_get_irq(struct kvm *kvm, struct kvm_vcpu *vcpu,
> u32 intid);
> bool vgic_queue_irq(struct kvm *kvm, struct vgic_irq *irq);
> diff --git a/virt/kvm/arm/vgic/vgic_mmio.c b/virt/kvm/arm/vgic/vgic_mmio.c
> index 2d10c06..13e101f 100644
> --- a/virt/kvm/arm/vgic/vgic_mmio.c
> +++ b/virt/kvm/arm/vgic/vgic_mmio.c
> @@ -606,7 +606,29 @@ static int vgic_mmio_read_v3_misc(struct kvm_vcpu *vcpu,
> struct kvm_io_device *this,
> gpa_t addr, int len, void *val)
> {
> - /* TODO: implement */
> + struct vgic_io_device *iodev = container_of(this,
> + struct vgic_io_device, dev);
> + u32 value = 0;
> +
> + switch ((addr - iodev->base_addr) & ~3) {
> + case GICD_CTLR:
> + if (vcpu->kvm->arch.vgic.enabled)
> + value |= GICD_CTLR_ENABLE_SS_G1;
> + value |= GICD_CTLR_ARE_NS | GICD_CTLR_DS;
> + break;
> + case GICD_TYPER:
> + value = vcpu->kvm->arch.vgic.nr_spis + VGIC_NR_PRIVATE_IRQS;
> + value = (value >> 5) - 1;
> + value |= (INTERRUPT_ID_BITS_SPIS - 1) << 19;
> + break;
> + case GICD_IIDR:
> + value = (PRODUCT_ID_KVM << 24) | (IMPLEMENTER_ARM << 0);
> + break;
> + default:
> + return 0;
> + }
> +
> + write_mask32(value, addr & 3, len, val);
> return 0;
> }
>
> @@ -614,7 +636,19 @@ static int vgic_mmio_write_v3_misc(struct kvm_vcpu *vcpu,
> struct kvm_io_device *this,
> gpa_t addr, int len, const void *val)
> {
> - /* TODO: implement */
> + struct vgic_io_device *iodev = container_of(this,
> + struct vgic_io_device, dev);
> + bool enabled;
> +
> + /* These are not the bits you are looking for ... */

haha, nice. But I don't understand what this case is?

> + if (addr - iodev->base_addr > 0)
> + return 0;
> +
> + /* We only care about the enable bit, all other bits are WI. */
> + enabled = *(u8*)val & GICD_CTLR_ENABLE_SS_G1;
> +
> + vcpu->kvm->arch.vgic.enabled = enabled;

I think some of the comments from the v2 side apply here as well.

> +
> return 0;
> }
>
> --
> 2.7.3
>