[PATCH v7 12/19] KVM: ARM64: Add access handler for PMOVSSET and PMOVSCLR register

Marc Zyngier
2015-12-15T14:06:05Z

On 15/12/15 08:49, Shannon Zhao wrote:
> From: Shannon Zhao <shannon.zhao@linaro.org>
>
> Since the reset value of PMOVSSET and PMOVSCLR is UNKNOWN, use
> reset_unknown for its reset handler. Add a handler to emulate writing
> PMOVSSET or PMOVSCLR register.
>
> When writing non-zero value to PMOVSSET, pend PMU interrupt.

This comment doesn't match the code anymore

>
> Signed-off-by: Shannon Zhao <shannon.zhao@linaro.org>
> ---
> arch/arm64/kvm/sys_regs.c | 28 +++++++++++++++++++++++++---
> include/kvm/arm_pmu.h | 2 ++
> virt/kvm/arm/pmu.c | 20 ++++++++++++++++++++
> 3 files changed, 47 insertions(+), 3 deletions(-)
>
> diff --git a/arch/arm64/kvm/sys_regs.c b/arch/arm64/kvm/sys_regs.c
> index 594e53f..d1926c4 100644
> --- a/arch/arm64/kvm/sys_regs.c
> +++ b/arch/arm64/kvm/sys_regs.c
> @@ -669,6 +669,27 @@ static bool access_pmintenset(struct kvm_vcpu *vcpu, struct sys_reg_params *p,
> return true;
> }
>
> +static bool access_pmovsset(struct kvm_vcpu *vcpu, struct sys_reg_params *p,
> + const struct sys_reg_desc *r)
> +{
> + u64 mask = kvm_pmu_valid_counter_mask(vcpu);
> +
> + if (p->is_write) {
> + if (r->CRm & 0x2) {
> + /* accessing PMOVSSET_EL0 */
> + kvm_pmu_overflow_set(vcpu, p->regval & mask);
> + } else {
> + /* accessing PMOVSCLR_EL0 */
> + vcpu_sys_reg(vcpu, r->reg) &= mask;
> + vcpu_sys_reg(vcpu, r->reg) &= ~p->regval;

Same as the previous patch.

> + }
> + } else {
> + p->regval = vcpu_sys_reg(vcpu, r->reg) & mask;
> + }
> +
> + return true;
> +}
> +
> /* Silly macro to expand the DBG{BCR,BVR,WVR,WCR}n_EL1 registers in one go */
> #define DBG_BCR_BVR_WCR_WVR_EL1(n) \
> /* DBGBVRn_EL1 */ \
> @@ -876,7 +897,7 @@ static const struct sys_reg_desc sys_reg_descs[] = {
> access_pmcntenset, NULL, PMCNTENSET_EL0 },
> /* PMOVSCLR_EL0 */
> { Op0(0b11), Op1(0b011), CRn(0b1001), CRm(0b1100), Op2(0b011),
> - trap_raz_wi },
> + access_pmovsset, NULL, PMOVSSET_EL0 },
> /* PMSWINC_EL0 */
> { Op0(0b11), Op1(0b011), CRn(0b1001), CRm(0b1100), Op2(0b100),
> trap_raz_wi },
> @@ -903,7 +924,7 @@ static const struct sys_reg_desc sys_reg_descs[] = {
> trap_raz_wi },
> /* PMOVSSET_EL0 */
> { Op0(0b11), Op1(0b011), CRn(0b1001), CRm(0b1110), Op2(0b011),
> - trap_raz_wi },
> + access_pmovsset, reset_unknown, PMOVSSET_EL0 },
>
> /* TPIDR_EL0 */
> { Op0(0b11), Op1(0b011), CRn(0b1101), CRm(0b0000), Op2(0b010),
> @@ -1217,7 +1238,7 @@ static const struct sys_reg_desc cp15_regs[] = {
> { Op1( 0), CRn( 9), CRm(12), Op2( 0), access_pmcr },
> { Op1( 0), CRn( 9), CRm(12), Op2( 1), access_pmcntenset },
> { Op1( 0), CRn( 9), CRm(12), Op2( 2), access_pmcntenset },
> - { Op1( 0), CRn( 9), CRm(12), Op2( 3), trap_raz_wi },
> + { Op1( 0), CRn( 9), CRm(12), Op2( 3), access_pmovsset },
> { Op1( 0), CRn( 9), CRm(12), Op2( 5), access_pmselr },
> { Op1( 0), CRn( 9), CRm(12), Op2( 6), access_pmceid },
> { Op1( 0), CRn( 9), CRm(12), Op2( 7), access_pmceid },
> @@ -1227,6 +1248,7 @@ static const struct sys_reg_desc cp15_regs[] = {
> { Op1( 0), CRn( 9), CRm(14), Op2( 0), trap_raz_wi },
> { Op1( 0), CRn( 9), CRm(14), Op2( 1), access_pmintenset },
> { Op1( 0), CRn( 9), CRm(14), Op2( 2), access_pmintenset },
> + { Op1( 0), CRn( 9), CRm(14), Op2( 3), access_pmovsset },
>
> { Op1( 0), CRn(10), CRm( 2), Op2( 0), access_vm_reg, NULL, c10_PRRR },
> { Op1( 0), CRn(10), CRm( 2), Op2( 1), access_vm_reg, NULL, c10_NMRR },
> diff --git a/include/kvm/arm_pmu.h b/include/kvm/arm_pmu.h
> index 43c4117..93aea6a 100644
> --- a/include/kvm/arm_pmu.h
> +++ b/include/kvm/arm_pmu.h
> @@ -38,6 +38,7 @@ struct kvm_pmu {
> u64 kvm_pmu_get_counter_value(struct kvm_vcpu *vcpu, u64 select_idx);
> void kvm_pmu_disable_counter(struct kvm_vcpu *vcpu, u64 val);
> void kvm_pmu_enable_counter(struct kvm_vcpu *vcpu, u64 val);
> +void kvm_pmu_overflow_set(struct kvm_vcpu *vcpu, u64 val);
> void kvm_pmu_set_counter_event_type(struct kvm_vcpu *vcpu, u64 data,
> u64 select_idx);
> #else
> @@ -50,6 +51,7 @@ u64 kvm_pmu_get_counter_value(struct kvm_vcpu *vcpu, u64 select_idx)
> }
> void kvm_pmu_disable_counter(struct kvm_vcpu *vcpu, u64 val) {}
> void kvm_pmu_enable_counter(struct kvm_vcpu *vcpu, u64 val) {}
> +void kvm_pmu_overflow_set(struct kvm_vcpu *vcpu, u64 val) {}
> void kvm_pmu_set_counter_event_type(struct kvm_vcpu *vcpu, u64 data,
> u64 select_idx) {}
> #endif
> diff --git a/virt/kvm/arm/pmu.c b/virt/kvm/arm/pmu.c
> index 94bff0e..861471d 100644
> --- a/virt/kvm/arm/pmu.c
> +++ b/virt/kvm/arm/pmu.c
> @@ -130,6 +130,26 @@ void kvm_pmu_disable_counter(struct kvm_vcpu *vcpu, u64 val)
> }
>
> /**
> + * kvm_pmu_overflow_set - set PMU overflow interrupt
> + * @vcpu: The vcpu pointer
> + * @val: the value guest writes to PMOVSSET register
> + */
> +void kvm_pmu_overflow_set(struct kvm_vcpu *vcpu, u64 val)
> +{
> + u64 reg;
> +
> + if (val == 0)
> + return;
> +
> + vcpu_sys_reg(vcpu, PMOVSSET_EL0) |= val;
> + reg = vcpu_sys_reg(vcpu, PMOVSSET_EL0)
> + & vcpu_sys_reg(vcpu, PMCNTENSET_EL0)
> + & vcpu_sys_reg(vcpu, PMINTENSET_EL1);
> + if (reg != 0)
> + kvm_vcpu_kick(vcpu);
> +}
> +
> +/**
> * kvm_pmu_set_counter_event_type - set selected counter to monitor some event
> * @vcpu: The vcpu pointer
> * @data: The data guest writes to PMXEVTYPER_EL0
>

Thanks,

M.
--
Jazz is not dead. It just smells funny...