Re: [PATCH 07/31] KVM: arm/arm64: vgic-v3: Add accessors for the ICH_APxRn_EL2 registers

Auger Eric
2017-05-17T09:50:59Z

Hi,

On 03/05/2017 12:45, Marc Zyngier wrote:
> As we're about to access the Active Priority registers a lot more,
> let's define accessors that take the register number as a parameter.
>
> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
> ---
> virt/kvm/arm/hyp/vgic-v3-sr.c | 116 ++++++++++++++++++++++++++++++++++++------
> 1 file changed, 100 insertions(+), 16 deletions(-)
>
> diff --git a/virt/kvm/arm/hyp/vgic-v3-sr.c b/virt/kvm/arm/hyp/vgic-v3-sr.c
> index 32c3295929b0..990d9d1e85d0 100644
> --- a/virt/kvm/arm/hyp/vgic-v3-sr.c
> +++ b/virt/kvm/arm/hyp/vgic-v3-sr.c
> @@ -118,6 +118,90 @@ static void __hyp_text __gic_v3_set_lr(u64 val, int lr)
> }
> }
>
> +static void __hyp_text __vgic_v3_write_ap0rn(u32 val, int n)
> +{
> + switch (n) {
> + case 0:
> + write_gicreg(val, ICH_AP0R0_EL2);
> + break;
> + case 1:
> + write_gicreg(val, ICH_AP0R1_EL2);
> + break;
> + case 2:
> + write_gicreg(val, ICH_AP0R2_EL2);
> + break;
> + case 3:
> + write_gicreg(val, ICH_AP0R3_EL2);
> + break;
> + }
> +}
> +
> +static void __hyp_text __vgic_v3_write_ap1rn(u32 val, int n)
> +{
> + switch (n) {
> + case 0:
> + write_gicreg(val, ICH_AP1R0_EL2);
> + break;
> + case 1:
> + write_gicreg(val, ICH_AP1R1_EL2);
> + break;
> + case 2:
> + write_gicreg(val, ICH_AP1R2_EL2);
> + break;
> + case 3:
> + write_gicreg(val, ICH_AP1R3_EL2);
> + break;
> + }
> +}
> +
> +static u32 __hyp_text __vgic_v3_read_ap0rn(int n)
> +{
> + u32 val;
> +
> + switch (n) {
> + case 0:
> + val = read_gicreg(ICH_AP0R0_EL2);
> + break;
> + case 1:
> + val = read_gicreg(ICH_AP0R1_EL2);
> + break;
> + case 2:
> + val = read_gicreg(ICH_AP0R2_EL2);
> + break;
> + case 3:
> + val = read_gicreg(ICH_AP0R3_EL2);
> + break;
> + default:
> + unreachable();
I am not familiar with that macro. For my curiosity why is it used here
and not in write functions.

Besides Mark's comment,

Reviewed-by: Eric Auger <eric.auger@redhat.com>

Eric
> + }
> +
> + return val;
> +}
> +
> +static u32 __hyp_text __vgic_v3_read_ap1rn(int n)
> +{
> + u32 val;
> +
> + switch (n) {
> + case 0:
> + val = read_gicreg(ICH_AP1R0_EL2);
> + break;
> + case 1:
> + val = read_gicreg(ICH_AP1R1_EL2);
> + break;
> + case 2:
> + val = read_gicreg(ICH_AP1R2_EL2);
> + break;
> + case 3:
> + val = read_gicreg(ICH_AP1R3_EL2);
> + break;
> + default:
> + unreachable();
> + }
> +
> + return val;
> +}
> +
> void __hyp_text __vgic_v3_save_state(struct kvm_vcpu *vcpu)
> {
> struct vgic_v3_cpu_if *cpu_if = &vcpu->arch.vgic_cpu.vgic_v3;
> @@ -154,22 +238,22 @@ void __hyp_text __vgic_v3_save_state(struct kvm_vcpu *vcpu)
>
> switch (nr_pre_bits) {
> case 7:
> - cpu_if->vgic_ap0r[3] = read_gicreg(ICH_AP0R3_EL2);
> - cpu_if->vgic_ap0r[2] = read_gicreg(ICH_AP0R2_EL2);
> + cpu_if->vgic_ap0r[3] = __vgic_v3_read_ap0rn(3);
> + cpu_if->vgic_ap0r[2] = __vgic_v3_read_ap0rn(2);
> case 6:
> - cpu_if->vgic_ap0r[1] = read_gicreg(ICH_AP0R1_EL2);
> + cpu_if->vgic_ap0r[1] = __vgic_v3_read_ap0rn(1);
> default:
> - cpu_if->vgic_ap0r[0] = read_gicreg(ICH_AP0R0_EL2);
> + cpu_if->vgic_ap0r[0] = __vgic_v3_read_ap0rn(0);
> }
>
> switch (nr_pre_bits) {
> case 7:
> - cpu_if->vgic_ap1r[3] = read_gicreg(ICH_AP1R3_EL2);
> - cpu_if->vgic_ap1r[2] = read_gicreg(ICH_AP1R2_EL2);
> + cpu_if->vgic_ap1r[3] = __vgic_v3_read_ap1rn(3);
> + cpu_if->vgic_ap1r[2] = __vgic_v3_read_ap1rn(2);
> case 6:
> - cpu_if->vgic_ap1r[1] = read_gicreg(ICH_AP1R1_EL2);
> + cpu_if->vgic_ap1r[1] = __vgic_v3_read_ap1rn(1);
> default:
> - cpu_if->vgic_ap1r[0] = read_gicreg(ICH_AP1R0_EL2);
> + cpu_if->vgic_ap1r[0] = __vgic_v3_read_ap1rn(0);
> }
> } else {
> cpu_if->vgic_elrsr = 0xffff;
> @@ -224,22 +308,22 @@ void __hyp_text __vgic_v3_restore_state(struct kvm_vcpu *vcpu)
>
> switch (nr_pre_bits) {
> case 7:
> - write_gicreg(cpu_if->vgic_ap0r[3], ICH_AP0R3_EL2);
> - write_gicreg(cpu_if->vgic_ap0r[2], ICH_AP0R2_EL2);
> + __vgic_v3_write_ap0rn(cpu_if->vgic_ap0r[3], 3);
> + __vgic_v3_write_ap0rn(cpu_if->vgic_ap0r[2], 2);
> case 6:
> - write_gicreg(cpu_if->vgic_ap0r[1], ICH_AP0R1_EL2);
> + __vgic_v3_write_ap0rn(cpu_if->vgic_ap0r[1], 1);
> default:
> - write_gicreg(cpu_if->vgic_ap0r[0], ICH_AP0R0_EL2);
> + __vgic_v3_write_ap0rn(cpu_if->vgic_ap0r[0], 0);
> }
>
> switch (nr_pre_bits) {
> case 7:
> - write_gicreg(cpu_if->vgic_ap1r[3], ICH_AP1R3_EL2);
> - write_gicreg(cpu_if->vgic_ap1r[2], ICH_AP1R2_EL2);
> + __vgic_v3_write_ap1rn(cpu_if->vgic_ap1r[3], 3);
> + __vgic_v3_write_ap1rn(cpu_if->vgic_ap1r[2], 2);
> case 6:
> - write_gicreg(cpu_if->vgic_ap1r[1], ICH_AP1R1_EL2);
> + __vgic_v3_write_ap1rn(cpu_if->vgic_ap1r[1], 1);
> default:
> - write_gicreg(cpu_if->vgic_ap1r[0], ICH_AP1R0_EL2);
> + __vgic_v3_write_ap1rn(cpu_if->vgic_ap1r[0], 0);
> }
>
> for (i = 0; i < used_lrs; i++)
>