Re: [PATCH v8 5/7] arm/arm64: vgic: Introduce VENG0 and VENG1 fields to vmcr struct

[Christoffer Dall <christoffer.dall@linaro.org>]

On Fri, Nov 04, 2016 at 04:43:31PM +0530, vijay.kilari@gmail.com wrote:
> From: Vijaya Kumar K <Vijaya.Kumar@cavium.com>
> 
> ICC_VMCR_EL2 supports virtual access to ICC_IGRPEN1_EL1.Enable
> and ICC_IGRPEN0_EL1.Enable fields. Add grpen0 and grpen1 member
> variables to struct vmcr to support read and write of these fields.
> 
> Also refactor vgic_set_vmcr and vgic_get_vmcr() code.
> Drop ICH_VMCR_CTLR_SHIFT and ICH_VMCR_CTLR_MASK macros and instead
> use ICH_VMCR_EOI* and ICH_VMCR_CBPR* macros
> .
> Signed-off-by: Vijaya Kumar K <Vijaya.Kumar@cavium.com>
> ---
>  include/linux/irqchip/arm-gic-v3.h |  2 --
>  virt/kvm/arm/vgic/vgic-mmio-v2.c   | 16 ----------------
>  virt/kvm/arm/vgic/vgic-mmio.c      | 16 ++++++++++++++++
>  virt/kvm/arm/vgic/vgic-v3.c        | 10 ++++++++--
>  virt/kvm/arm/vgic/vgic.h           |  5 +++++
>  5 files changed, 29 insertions(+), 20 deletions(-)
> 
> diff --git a/include/linux/irqchip/arm-gic-v3.h b/include/linux/irqchip/arm-gic-v3.h
> index d48d886..61646aa 100644
> --- a/include/linux/irqchip/arm-gic-v3.h
> +++ b/include/linux/irqchip/arm-gic-v3.h
> @@ -404,8 +404,6 @@
>  #define ICH_HCR_EN			(1 << 0)
>  #define ICH_HCR_UIE			(1 << 1)
>  
> -#define ICH_VMCR_CTLR_SHIFT		0
> -#define ICH_VMCR_CTLR_MASK		(0x21f << ICH_VMCR_CTLR_SHIFT)
>  #define ICH_VMCR_CBPR_SHIFT		4
>  #define ICH_VMCR_CBPR_MASK		(1 << ICH_VMCR_CBPR_SHIFT)
>  #define ICH_VMCR_EOIM_SHIFT		9
> diff --git a/virt/kvm/arm/vgic/vgic-mmio-v2.c b/virt/kvm/arm/vgic/vgic-mmio-v2.c
> index 2cb04b7..ad353b5 100644
> --- a/virt/kvm/arm/vgic/vgic-mmio-v2.c
> +++ b/virt/kvm/arm/vgic/vgic-mmio-v2.c
> @@ -212,22 +212,6 @@ static void vgic_mmio_write_sgipends(struct kvm_vcpu *vcpu,
>  	}
>  }
>  
> -static void vgic_set_vmcr(struct kvm_vcpu *vcpu, struct vgic_vmcr *vmcr)
> -{
> -	if (kvm_vgic_global_state.type == VGIC_V2)
> -		vgic_v2_set_vmcr(vcpu, vmcr);
> -	else
> -		vgic_v3_set_vmcr(vcpu, vmcr);
> -}
> -
> -static void vgic_get_vmcr(struct kvm_vcpu *vcpu, struct vgic_vmcr *vmcr)
> -{
> -	if (kvm_vgic_global_state.type == VGIC_V2)
> -		vgic_v2_get_vmcr(vcpu, vmcr);
> -	else
> -		vgic_v3_get_vmcr(vcpu, vmcr);
> -}
> -
>  #define GICC_ARCH_VERSION_V2	0x2
>  
>  /* These are for userland accesses only, there is no guest-facing emulation. */
> diff --git a/virt/kvm/arm/vgic/vgic-mmio.c b/virt/kvm/arm/vgic/vgic-mmio.c
> index 9939d1d..173d6f0 100644
> --- a/virt/kvm/arm/vgic/vgic-mmio.c
> +++ b/virt/kvm/arm/vgic/vgic-mmio.c
> @@ -416,6 +416,22 @@ int vgic_validate_mmio_region_addr(struct kvm_device *dev,
>  	return -ENXIO;
>  }
>  
> +void vgic_set_vmcr(struct kvm_vcpu *vcpu, struct vgic_vmcr *vmcr)
> +{
> +	if (kvm_vgic_global_state.type == VGIC_V2)
> +		vgic_v2_set_vmcr(vcpu, vmcr);
> +	else
> +		vgic_v3_set_vmcr(vcpu, vmcr);
> +}
> +
> +void vgic_get_vmcr(struct kvm_vcpu *vcpu, struct vgic_vmcr *vmcr)
> +{
> +	if (kvm_vgic_global_state.type == VGIC_V2)
> +		vgic_v2_get_vmcr(vcpu, vmcr);
> +	else
> +		vgic_v3_get_vmcr(vcpu, vmcr);
> +}
> +
>  /*
>   * kvm_mmio_read_buf() returns a value in a format where it can be converted
>   * to a byte array and be directly observed as the guest wanted it to appear
> diff --git a/virt/kvm/arm/vgic/vgic-v3.c b/virt/kvm/arm/vgic/vgic-v3.c
> index 9f0dae3..967c295 100644
> --- a/virt/kvm/arm/vgic/vgic-v3.c
> +++ b/virt/kvm/arm/vgic/vgic-v3.c
> @@ -175,10 +175,13 @@ void vgic_v3_set_vmcr(struct kvm_vcpu *vcpu, struct vgic_vmcr *vmcrp)
>  {
>  	u32 vmcr;
>  
> -	vmcr  = (vmcrp->ctlr << ICH_VMCR_CTLR_SHIFT) & ICH_VMCR_CTLR_MASK;
> +	vmcr  = (vmcrp->ctlr << ICH_VMCR_CBPR_SHIFT) & ICH_VMCR_CBPR_MASK;
> +	vmcr |= (vmcrp->ctlr << ICH_VMCR_EOIM_SHIFT) & ICH_VMCR_EOIM_MASK;

This looks weird:  The EOImode field is bit[2] in the CTLR, and VEOIM is
bit[9] in the ICH_VMCR, but you're just shifting the ctlr field left by
9 and then masking off everything by bit 9, so you'll end with never
being able to set VEOIM I think...

Also, we do we now forget about VFIQEn and VAckCtl?  The latter I can
understand because it's deprecated, but why the first?  This particular
piece of information would be very nice to have in the commit message.

>  	vmcr |= (vmcrp->abpr << ICH_VMCR_BPR1_SHIFT) & ICH_VMCR_BPR1_MASK;
>  	vmcr |= (vmcrp->bpr << ICH_VMCR_BPR0_SHIFT) & ICH_VMCR_BPR0_MASK;
>  	vmcr |= (vmcrp->pmr << ICH_VMCR_PMR_SHIFT) & ICH_VMCR_PMR_MASK;
> +	vmcr |= (vmcrp->grpen0 << ICH_VMCR_ENG0_SHIFT) & ICH_VMCR_ENG0_MASK;
> +	vmcr |= (vmcrp->grpen1 << ICH_VMCR_ENG1_SHIFT) & ICH_VMCR_ENG1_MASK;
>  
>  	vcpu->arch.vgic_cpu.vgic_v3.vgic_vmcr = vmcr;
>  }
> @@ -187,10 +190,13 @@ void vgic_v3_get_vmcr(struct kvm_vcpu *vcpu, struct vgic_vmcr *vmcrp)
>  {
>  	u32 vmcr = vcpu->arch.vgic_cpu.vgic_v3.vgic_vmcr;
>  
> -	vmcrp->ctlr = (vmcr & ICH_VMCR_CTLR_MASK) >> ICH_VMCR_CTLR_SHIFT;
> +	vmcrp->ctlr = (vmcr & ICH_VMCR_CBPR_MASK) >> ICH_VMCR_CBPR_SHIFT;
> +	vmcrp->ctlr |= (vmcr & ICH_VMCR_EOIM_MASK) >> ICH_VMCR_EOIM_SHIFT;
>  	vmcrp->abpr = (vmcr & ICH_VMCR_BPR1_MASK) >> ICH_VMCR_BPR1_SHIFT;
>  	vmcrp->bpr  = (vmcr & ICH_VMCR_BPR0_MASK) >> ICH_VMCR_BPR0_SHIFT;
>  	vmcrp->pmr  = (vmcr & ICH_VMCR_PMR_MASK) >> ICH_VMCR_PMR_SHIFT;
> +	vmcrp->grpen0 = (vmcr & ICH_VMCR_ENG0_MASK) >> ICH_VMCR_ENG0_SHIFT;
> +	vmcrp->grpen1 = (vmcr & ICH_VMCR_ENG1_MASK) >> ICH_VMCR_ENG1_SHIFT;
>  }
>  
>  #define INITIAL_PENDBASER_VALUE						  \
> diff --git a/virt/kvm/arm/vgic/vgic.h b/virt/kvm/arm/vgic/vgic.h
> index d901b0c..c461f6b 100644
> --- a/virt/kvm/arm/vgic/vgic.h
> +++ b/virt/kvm/arm/vgic/vgic.h
> @@ -63,6 +63,9 @@ struct vgic_vmcr {
>  	u32	abpr;
>  	u32	bpr;
>  	u32	pmr;
> +	/* Below member variable are valid only for GICv3 */
> +	u32	grpen0;
> +	u32	grpen1;
>  };
>  
>  struct vgic_irq *vgic_get_irq(struct kvm *kvm, struct kvm_vcpu *vcpu,
> @@ -150,6 +153,8 @@ static inline int vgic_its_inject_msi(struct kvm *kvm, struct kvm_msi *msi)
>  #endif
>  
>  int kvm_register_vgic_device(unsigned long type);
> +void vgic_set_vmcr(struct kvm_vcpu *vcpu, struct vgic_vmcr *vmcr);
> +void vgic_get_vmcr(struct kvm_vcpu *vcpu, struct vgic_vmcr *vmcr);
>  int vgic_lazy_init(struct kvm *kvm);
>  int vgic_init(struct kvm *kvm);
>  
> -- 
> 1.9.1
> 

Thanks,
-Christoffer