[PATCH 8/8] KVM: arm-vgic: Support CPU interface reg access
Christoffer Dall
christoffer.dall at linaro.org
Wed Sep 25 17:30:41 EDT 2013
On Sun, Aug 25, 2013 at 04:24:20PM +0100, Alexander Graf wrote:
>
> On 23.08.2013, at 20:20, Christoffer Dall wrote:
>
> > Implement support for the CPU interface register access driven by MMIO
> > address offsets from the CPU interface base address. Useful for user
> > space to support save/restore of the VGIC state.
> >
> > This commit adds support only for the same logic as the current VGIC
> > support, and no more. For example, the active priority registers are
> > handled as RAZ/WI, just like setting priorities on the emulated
> > distributor.
> >
> > Signed-off-by: Christoffer Dall <christoffer.dall at linaro.org>
> > ---
> > virt/kvm/arm/vgic.c | 66 +++++++++++++++++++++++++++++++++++++++++++++++----
> > 1 file changed, 62 insertions(+), 4 deletions(-)
> >
> > diff --git a/virt/kvm/arm/vgic.c b/virt/kvm/arm/vgic.c
> > index d44b5a1..257dbae 100644
> > --- a/virt/kvm/arm/vgic.c
> > +++ b/virt/kvm/arm/vgic.c
> > @@ -1684,9 +1684,67 @@ int kvm_vgic_addr(struct kvm *kvm, unsigned long type, u64 *addr, bool write)
> > static bool handle_cpu_mmio_misc(struct kvm_vcpu *vcpu,
> > struct kvm_exit_mmio *mmio, phys_addr_t offset)
> > {
> > - return true;
> > + struct vgic_cpu *vgic_cpu = &vcpu->arch.vgic_cpu;
> > + u32 reg, mask = 0, shift = 0;
> > + bool updated = false;
> > +
> > + switch (offset & ~0x3) {
> > + case GIC_CPU_CTRL:
> > + mask = GICH_VMCR_CTRL_MASK;
> > + shift = GICH_VMCR_CTRL_SHIFT;
> > + break;
> > + case GIC_CPU_PRIMASK:
> > + mask = GICH_VMCR_PRIMASK_MASK;
> > + shift = GICH_VMCR_PRIMASK_SHIFT;
> > + break;
> > + case GIC_CPU_BINPOINT:
> > + mask = GICH_VMCR_BINPOINT_MASK;
> > + shift = GICH_VMCR_BINPOINT_SHIFT;
> > + break;
> > + case GIC_CPU_ALIAS_BINPOINT:
> > + mask = GICH_VMCR_ALIAS_BINPOINT_MASK;
> > + shift = GICH_VMCR_ALIAS_BINPOINT_SHIFT;
> > + break;
> > + }
> > +
> > + if (!mmio->is_write) {
> > + reg = (vgic_cpu->vgic_vmcr & mask) >> shift;
> > + memcpy(mmio->data, ®, sizeof(reg));
> > + } else {
> > + memcpy(®, mmio->data, sizeof(reg));
> > + reg = (reg << shift) & mask;
> > + if (reg != (vgic_cpu->vgic_vmcr & mask))
> > + updated = true;
> > + vgic_cpu->vgic_vmcr &= ~mask;
> > + vgic_cpu->vgic_vmcr |= reg;
> > + }
> > + return updated;
> > +}
> > +
> > +static bool handle_mmio_abpr(struct kvm_vcpu *vcpu,
> > + struct kvm_exit_mmio *mmio, phys_addr_t offset)
> > +{
> > + return handle_cpu_mmio_misc(vcpu, mmio, GIC_CPU_ALIAS_BINPOINT);
> > +}
> > +
> > +static bool handle_cpu_mmio_ident(struct kvm_vcpu *vcpu,
> > + struct kvm_exit_mmio *mmio,
> > + phys_addr_t offset)
> > +{
> > + u32 reg;
> > +
> > + if (mmio->is_write)
> > + return false;
> > +
> > + reg = 0x0002043B;
>
> This wants a comment and probably also a #define :).
>
Marc, where does the 0x4b0 product id code come from for the distributor
IIDR?
Would this be satisfying?
diff --git a/virt/kvm/arm/vgic.c b/virt/kvm/arm/vgic.c
index 5214424..558be38 100644
--- a/virt/kvm/arm/vgic.c
+++ b/virt/kvm/arm/vgic.c
@@ -71,6 +71,9 @@
#define VGIC_ADDR_UNDEF (-1)
#define IS_VGIC_ADDR_UNDEF(_x) ((_x) == VGIC_ADDR_UNDEF)
+#define GIC_PRODUCT_ID 0x4b0
+#define ARM_JEP106_IMPLEMENTER 0x43b
+
/* Physical address of vgic virtual cpu interface */
static phys_addr_t vgic_vcpu_base;
@@ -331,7 +334,7 @@ static bool handle_mmio_misc(struct kvm_vcpu *vcpu,
break;
case 8: /* IIDR */
- reg = 0x4B00043B;
+ reg = (GIC_PRODUCT_ID << 20) | ARM_JEP106_IMPLEMENTER;
vgic_reg_access(mmio, ®, word_offset,
ACCESS_READ_VALUE | ACCESS_WRITE_IGNORED);
break;
@@ -1734,7 +1737,7 @@ static bool handle_cpu_mmio_ident(struct kvm_vcpu *vcpu,
if (mmio->is_write)
return false;
- reg = 0x0002043B;
+ reg = (GIC_PRODUCT_ID << 20) | (0x2 << 16) | ARM_JEP106_IMPLEMENTER;
mmio_data_write(mmio, ~0, reg);
return false;
}
Thanks,
-Christoffer
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