[PATCH v3 25/55] KVM: arm/arm64: vgic-new: Add PENDING registers handlers

[Christoffer Dall]

On Fri, May 06, 2016 at 11:45:38AM +0100, Andre Przywara wrote:
> The pending register handlers are shared between the v2 and v3
> emulation, so their implementation goes into vgic-mmio.c, to be easily
> referenced from the v3 emulation as well later.
> For level triggered interrupts the real line level is unaffected by
> this write, so we keep this state separate and combine it with the
> device's level to get the actual pending state.
> 
> Signed-off-by: Andre Przywara <andre.przywara at arm.com>
> ---
> Changelog RFC..v1:
> - remove IRQ lock from read handler
> - remove TODO from clear pending handler
> 
> Changelog v1 .. v2:
> - adapt to new MMIO framework
> 
>  virt/kvm/arm/vgic/vgic-mmio-v2.c |  4 +--
>  virt/kvm/arm/vgic/vgic-mmio.c    | 60 ++++++++++++++++++++++++++++++++++++++++
>  virt/kvm/arm/vgic/vgic-mmio.h    | 12 ++++++++
>  3 files changed, 74 insertions(+), 2 deletions(-)
> 
> diff --git a/virt/kvm/arm/vgic/vgic-mmio-v2.c b/virt/kvm/arm/vgic/vgic-mmio-v2.c
> index 448d1da..4b87e0a 100644
> --- a/virt/kvm/arm/vgic/vgic-mmio-v2.c
> +++ b/virt/kvm/arm/vgic/vgic-mmio-v2.c
> @@ -76,9 +76,9 @@ static const struct vgic_register_region vgic_v2_dist_registers[] = {
>  	REGISTER_DESC_WITH_BITS_PER_IRQ(GIC_DIST_ENABLE_CLEAR,
>  		vgic_mmio_read_enable, vgic_mmio_write_cenable, 1),
>  	REGISTER_DESC_WITH_BITS_PER_IRQ(GIC_DIST_PENDING_SET,
> -		vgic_mmio_read_raz, vgic_mmio_write_wi, 1),
> +		vgic_mmio_read_pending, vgic_mmio_write_spending, 1),
>  	REGISTER_DESC_WITH_BITS_PER_IRQ(GIC_DIST_PENDING_CLEAR,
> -		vgic_mmio_read_raz, vgic_mmio_write_wi, 1),
> +		vgic_mmio_read_pending, vgic_mmio_write_cpending, 1),
>  	REGISTER_DESC_WITH_BITS_PER_IRQ(GIC_DIST_ACTIVE_SET,
>  		vgic_mmio_read_raz, vgic_mmio_write_wi, 1),
>  	REGISTER_DESC_WITH_BITS_PER_IRQ(GIC_DIST_ACTIVE_CLEAR,
> diff --git a/virt/kvm/arm/vgic/vgic-mmio.c b/virt/kvm/arm/vgic/vgic-mmio.c
> index 077ae86..4df1af7 100644
> --- a/virt/kvm/arm/vgic/vgic-mmio.c
> +++ b/virt/kvm/arm/vgic/vgic-mmio.c
> @@ -102,6 +102,66 @@ void vgic_mmio_write_cenable(struct kvm_vcpu *vcpu,
>  	}
>  }
>  
> +unsigned long vgic_mmio_read_pending(struct kvm_vcpu *vcpu,
> +				     gpa_t addr, unsigned int len)
> +{
> +	u32 intid = (addr & 0x7f) * 8;
> +	u32 value = 0;
> +	int i;
> +
> +	/* Loop over all IRQs affected by this read */
> +	for (i = 0; i < len * 8; i++) {
> +		struct vgic_irq *irq = vgic_get_irq(vcpu->kvm, vcpu, intid + i);
> +
> +		if (irq->pending)
> +			value |= (1U << i);

same question as on the previous patch

> +	}
> +
> +	return extract_bytes(value, addr & 3, len);
> +}
> +
> +void vgic_mmio_write_spending(struct kvm_vcpu *vcpu,
> +			      gpa_t addr, unsigned int len,
> +			      unsigned long val)
> +{
> +	u32 intid = (addr & 0x7f) * 8;
> +	int i;
> +
> +	for_each_set_bit(i, &val, len * 8) {
> +		struct vgic_irq *irq = vgic_get_irq(vcpu->kvm, vcpu, intid + i);
> +
> +		spin_lock(&irq->irq_lock);
> +		irq->pending = true;
> +		if (irq->config == VGIC_CONFIG_LEVEL)
> +			irq->soft_pending = true;
> +
> +		vgic_queue_irq_unlock(vcpu->kvm, irq);
> +	}
> +}
> +
> +void vgic_mmio_write_cpending(struct kvm_vcpu *vcpu,
> +			      gpa_t addr, unsigned int len,
> +			      unsigned long val)
> +{
> +	u32 intid = (addr & 0x7f) * 8;
> +	int i;
> +
> +	for_each_set_bit(i, &val, len * 8) {
> +		struct vgic_irq *irq = vgic_get_irq(vcpu->kvm, vcpu, intid + i);
> +
> +		spin_lock(&irq->irq_lock);
> +
> +		if (irq->config == VGIC_CONFIG_LEVEL) {
> +			irq->soft_pending = false;
> +			irq->pending = irq->line_level;
> +		} else {
> +			irq->pending = false;
> +		}
> +
> +		spin_unlock(&irq->irq_lock);
> +	}
> +}
> +
>  static int match_region(const void *key, const void *elt)
>  {
>  	const unsigned int offset = (unsigned long)key;
> diff --git a/virt/kvm/arm/vgic/vgic-mmio.h b/virt/kvm/arm/vgic/vgic-mmio.h
> index 188909a..d4fc029 100644
> --- a/virt/kvm/arm/vgic/vgic-mmio.h
> +++ b/virt/kvm/arm/vgic/vgic-mmio.h
> @@ -85,6 +85,18 @@ void vgic_mmio_write_cenable(struct kvm_vcpu *vcpu,
>  			     gpa_t addr, unsigned int len,
>  			     unsigned long val);
>  
> +unsigned long vgic_mmio_read_pending(struct kvm_vcpu *vcpu,
> +				     gpa_t addr, unsigned int len);
> +
> +void vgic_mmio_write_spending(struct kvm_vcpu *vcpu,
> +			      gpa_t addr, unsigned int len,
> +			      unsigned long val);
> +
> +void vgic_mmio_write_cpending(struct kvm_vcpu *vcpu,
> +			      gpa_t addr, unsigned int len,
> +			      unsigned long val);
> +
> +
>  unsigned int vgic_v2_init_dist_iodev(struct vgic_io_device *dev);
>  
>  #endif
> -- 
> 2.7.3
> 

Otherwise this looks good.

Thanks,
-Christoffer