[PATCH v4 06/21] KVM: ARM64: Add reset and access handlers for PMCEID0 and PMCEID1 register
Marc Zyngier
marc.zyngier at arm.com
Mon Nov 30 03:42:30 PST 2015
On Fri, 30 Oct 2015 14:21:48 +0800
Shannon Zhao <zhaoshenglong at huawei.com> wrote:
> From: Shannon Zhao <shannon.zhao at linaro.org>
>
> Add reset handler which gets host value of PMCEID0 or PMCEID1. Since
> write action to PMCEID0 or PMCEID1 is ignored, add a new case for this.
>
> Signed-off-by: Shannon Zhao <shannon.zhao at linaro.org>
> ---
> arch/arm64/kvm/sys_regs.c | 29 +++++++++++++++++++++++++----
> 1 file changed, 25 insertions(+), 4 deletions(-)
>
> diff --git a/arch/arm64/kvm/sys_regs.c b/arch/arm64/kvm/sys_regs.c
> index 35d232e..cb82b15 100644
> --- a/arch/arm64/kvm/sys_regs.c
> +++ b/arch/arm64/kvm/sys_regs.c
> @@ -469,6 +469,19 @@ static void reset_pmcr(struct kvm_vcpu *vcpu, const struct sys_reg_desc *r)
> vcpu_sysreg_write(vcpu, r, val);
> }
>
> +static void reset_pmceid(struct kvm_vcpu *vcpu, const struct sys_reg_desc *r)
> +{
> + u64 pmceid;
> +
> + if (r->reg == PMCEID0_EL0 || r->reg == c9_PMCEID0)
That feels wrong. We should only reset the 64bit view of the sysregs,
as the 32bit view is directly mapped to it.
> + asm volatile("mrs %0, pmceid0_el0\n" : "=r" (pmceid));
> + else
> + /* PMCEID1_EL0 or c9_PMCEID1 */
> + asm volatile("mrs %0, pmceid1_el0\n" : "=r" (pmceid));
> +
> + vcpu_sysreg_write(vcpu, r, pmceid);
> +}
> +
> /* PMU registers accessor. */
> static bool access_pmu_regs(struct kvm_vcpu *vcpu,
> const struct sys_reg_params *p,
> @@ -486,6 +499,9 @@ static bool access_pmu_regs(struct kvm_vcpu *vcpu,
> vcpu_sys_reg(vcpu, r->reg) = val;
> break;
> }
> + case PMCEID0_EL0:
> + case PMCEID1_EL0:
> + return ignore_write(vcpu, p);
> default:
> vcpu_sys_reg(vcpu, r->reg) = *vcpu_reg(vcpu, p->Rt);
> break;
> @@ -710,10 +726,10 @@ static const struct sys_reg_desc sys_reg_descs[] = {
> access_pmu_regs, reset_unknown, PMSELR_EL0 },
> /* PMCEID0_EL0 */
> { Op0(0b11), Op1(0b011), CRn(0b1001), CRm(0b1100), Op2(0b110),
> - trap_raz_wi },
> + access_pmu_regs, reset_pmceid, PMCEID0_EL0 },
> /* PMCEID1_EL0 */
> { Op0(0b11), Op1(0b011), CRn(0b1001), CRm(0b1100), Op2(0b111),
> - trap_raz_wi },
> + access_pmu_regs, reset_pmceid, PMCEID1_EL0 },
> /* PMCCNTR_EL0 */
> { Op0(0b11), Op1(0b011), CRn(0b1001), CRm(0b1101), Op2(0b000),
> trap_raz_wi },
> @@ -943,6 +959,9 @@ static bool access_pmu_cp15_regs(struct kvm_vcpu *vcpu,
> vcpu_cp15(vcpu, r->reg) = val;
> break;
> }
> + case c9_PMCEID0:
> + case c9_PMCEID1:
> + return ignore_write(vcpu, p);
> default:
> vcpu_cp15(vcpu, r->reg) = *vcpu_reg(vcpu, p->Rt);
> break;
> @@ -1000,8 +1019,10 @@ static const struct sys_reg_desc cp15_regs[] = {
> { Op1( 0), CRn( 9), CRm(12), Op2( 3), trap_raz_wi },
> { Op1( 0), CRn( 9), CRm(12), Op2( 5), access_pmu_cp15_regs,
> reset_unknown_cp15, c9_PMSELR },
> - { Op1( 0), CRn( 9), CRm(12), Op2( 6), trap_raz_wi },
> - { Op1( 0), CRn( 9), CRm(12), Op2( 7), trap_raz_wi },
> + { Op1( 0), CRn( 9), CRm(12), Op2( 6), access_pmu_cp15_regs,
> + reset_pmceid, c9_PMCEID0 },
> + { Op1( 0), CRn( 9), CRm(12), Op2( 7), access_pmu_cp15_regs,
> + reset_pmceid, c9_PMCEID1 },
and as a consequence, this hunk should be reworked.
> { Op1( 0), CRn( 9), CRm(13), Op2( 0), trap_raz_wi },
> { Op1( 0), CRn( 9), CRm(13), Op2( 1), trap_raz_wi },
> { Op1( 0), CRn( 9), CRm(13), Op2( 2), trap_raz_wi },
Thanks,
M.
--
Jazz is not dead. It just smells funny.
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