[PATCH v2 03/10] KVM: arm/arm64: vgic: Convert struct vgic_lr to use bitfields
Christoffer Dall
christoffer.dall at linaro.org
Fri Jul 17 15:15:34 PDT 2015
On Wed, Jul 08, 2015 at 06:56:35PM +0100, Marc Zyngier wrote:
> As we're about to cram more information in the vgic_lr structure
> (HW interrupt number and additional state information), we switch
> to a layout similar to the HW's:
>
> - use bitfields to save space (we don't need more than 10 bits
> to represent the irq numbers)
> - source CPU and HW interrupt can share the same field, as
> a SGI doesn't have a physical line.
>
> Signed-off-by: Marc Zyngier <marc.zyngier at arm.com>
> Reviewed-by: Alex Bennée <alex.bennee at linaro.org>
> ---
> include/kvm/arm_vgic.h | 10 +++++++---
> 1 file changed, 7 insertions(+), 3 deletions(-)
>
> diff --git a/include/kvm/arm_vgic.h b/include/kvm/arm_vgic.h
> index 133ea00..4f9fa1d 100644
> --- a/include/kvm/arm_vgic.h
> +++ b/include/kvm/arm_vgic.h
> @@ -95,11 +95,15 @@ enum vgic_type {
> #define LR_STATE_ACTIVE (1 << 1)
> #define LR_STATE_MASK (3 << 0)
> #define LR_EOI_INT (1 << 2)
> +#define LR_HW (1 << 3)
>
> struct vgic_lr {
> - u16 irq;
> - u8 source;
> - u8 state;
> + unsigned irq:10;
> + union {
> + unsigned hwirq:10;
> + unsigned source:8;
why 8? why not 3?
> + };
> + unsigned state:4;
> };
>
> struct vgic_vmcr {
> --
> 2.1.4
>
otherwise:
Reviewed-by: Christoffer Dall <christoffer.dall at linaro.org>
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