[PATCH v10 08/21] KVM: ARM64: Add access handler for event type register
Andrew Jones
drjones at redhat.com
Thu Jan 28 12:11:59 PST 2016
On Wed, Jan 27, 2016 at 11:51:36AM +0800, Shannon Zhao wrote:
> From: Shannon Zhao <shannon.zhao at linaro.org>
>
> These kind of registers include PMEVTYPERn, PMCCFILTR and PMXEVTYPER
> which is mapped to PMEVTYPERn or PMCCFILTR.
>
> The access handler translates all aarch32 register offsets to aarch64
> ones and uses vcpu_sys_reg() to access their values to avoid taking care
> of big endian.
>
> When writing to these registers, create a perf_event for the selected
> event type.
>
> Signed-off-by: Shannon Zhao <shannon.zhao at linaro.org>
> ---
> arch/arm64/kvm/sys_regs.c | 140 +++++++++++++++++++++++++++++++++++++++++++++-
> 1 file changed, 138 insertions(+), 2 deletions(-)
>
> diff --git a/arch/arm64/kvm/sys_regs.c b/arch/arm64/kvm/sys_regs.c
> index 06257e2..298ae94 100644
> --- a/arch/arm64/kvm/sys_regs.c
> +++ b/arch/arm64/kvm/sys_regs.c
> @@ -513,6 +513,54 @@ static bool access_pmceid(struct kvm_vcpu *vcpu, struct sys_reg_params *p,
> return true;
> }
>
> +static bool pmu_counter_idx_valid(struct kvm_vcpu *vcpu, u64 idx)
> +{
> + u64 pmcr, val;
> +
> + pmcr = vcpu_sys_reg(vcpu, PMCR_EL0);
> + val = (pmcr >> ARMV8_PMCR_N_SHIFT) & ARMV8_PMCR_N_MASK;
> + if (idx >= val && idx != ARMV8_CYCLE_IDX)
> + return false;
> +
> + return true;
> +}
> +
> +static bool access_pmu_evtyper(struct kvm_vcpu *vcpu, struct sys_reg_params *p,
> + const struct sys_reg_desc *r)
> +{
> + u64 idx, reg;
> +
> + if (!kvm_arm_pmu_v3_ready(vcpu))
> + return trap_raz_wi(vcpu, p, r);
> +
> + if (r->CRn == 9 && r->CRm == 13 && r->Op2 == 1) {
> + /* PMXEVTYPER_EL0 */
> + idx = vcpu_sys_reg(vcpu, PMSELR_EL0) & ARMV8_COUNTER_MASK;
> + reg = PMEVTYPER0_EL0 + idx;
> + } else if (r->CRn == 14 && (r->CRm & 12) == 12) {
> + idx = ((r->CRm & 3) << 3) | (r->Op2 & 7);
> + if (idx == ARMV8_CYCLE_IDX)
> + reg = PMCCFILTR_EL0;
> + else
> + /* PMEVTYPERn_EL0 */
> + reg = PMEVTYPER0_EL0 + idx;
> + } else {
> + BUG();
> + }
> +
> + if (!pmu_counter_idx_valid(vcpu, idx))
> + return false;
> +
> + if (p->is_write) {
> + kvm_pmu_set_counter_event_type(vcpu, p->regval, idx);
> + vcpu_sys_reg(vcpu, reg) = p->regval & ARMV8_EVTYPE_MASK;
> + } else {
> + p->regval = vcpu_sys_reg(vcpu, reg) & ARMV8_EVTYPE_MASK;
Related to my comment in 5/21. Why should we need to mask it here when
reading it, since it was masked on writing?
> + }
> +
> + 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 */ \
> @@ -528,6 +576,13 @@ static bool access_pmceid(struct kvm_vcpu *vcpu, struct sys_reg_params *p,
> { Op0(0b10), Op1(0b000), CRn(0b0000), CRm((n)), Op2(0b111), \
> trap_wcr, reset_wcr, n, 0, get_wcr, set_wcr }
>
> +/* Macro to expand the PMEVTYPERn_EL0 register */
> +#define PMU_PMEVTYPER_EL0(n) \
> + /* PMEVTYPERn_EL0 */ \
> + { Op0(0b11), Op1(0b011), CRn(0b1110), \
> + CRm((0b1100 | (((n) >> 3) & 0x3))), Op2(((n) & 0x7)), \
> + access_pmu_evtyper, reset_unknown, (PMEVTYPER0_EL0 + n), }
> +
> /*
> * Architected system registers.
> * Important: Must be sorted ascending by Op0, Op1, CRn, CRm, Op2
> @@ -724,7 +779,7 @@ static const struct sys_reg_desc sys_reg_descs[] = {
> trap_raz_wi },
> /* PMXEVTYPER_EL0 */
> { Op0(0b11), Op1(0b011), CRn(0b1001), CRm(0b1101), Op2(0b001),
> - trap_raz_wi },
> + access_pmu_evtyper },
> /* PMXEVCNTR_EL0 */
> { Op0(0b11), Op1(0b011), CRn(0b1001), CRm(0b1101), Op2(0b010),
> trap_raz_wi },
> @@ -742,6 +797,45 @@ static const struct sys_reg_desc sys_reg_descs[] = {
> { Op0(0b11), Op1(0b011), CRn(0b1101), CRm(0b0000), Op2(0b011),
> NULL, reset_unknown, TPIDRRO_EL0 },
>
> + /* PMEVTYPERn_EL0 */
> + PMU_PMEVTYPER_EL0(0),
> + PMU_PMEVTYPER_EL0(1),
> + PMU_PMEVTYPER_EL0(2),
> + PMU_PMEVTYPER_EL0(3),
> + PMU_PMEVTYPER_EL0(4),
> + PMU_PMEVTYPER_EL0(5),
> + PMU_PMEVTYPER_EL0(6),
> + PMU_PMEVTYPER_EL0(7),
> + PMU_PMEVTYPER_EL0(8),
> + PMU_PMEVTYPER_EL0(9),
> + PMU_PMEVTYPER_EL0(10),
> + PMU_PMEVTYPER_EL0(11),
> + PMU_PMEVTYPER_EL0(12),
> + PMU_PMEVTYPER_EL0(13),
> + PMU_PMEVTYPER_EL0(14),
> + PMU_PMEVTYPER_EL0(15),
> + PMU_PMEVTYPER_EL0(16),
> + PMU_PMEVTYPER_EL0(17),
> + PMU_PMEVTYPER_EL0(18),
> + PMU_PMEVTYPER_EL0(19),
> + PMU_PMEVTYPER_EL0(20),
> + PMU_PMEVTYPER_EL0(21),
> + PMU_PMEVTYPER_EL0(22),
> + PMU_PMEVTYPER_EL0(23),
> + PMU_PMEVTYPER_EL0(24),
> + PMU_PMEVTYPER_EL0(25),
> + PMU_PMEVTYPER_EL0(26),
> + PMU_PMEVTYPER_EL0(27),
> + PMU_PMEVTYPER_EL0(28),
> + PMU_PMEVTYPER_EL0(29),
> + PMU_PMEVTYPER_EL0(30),
> + /* PMCCFILTR_EL0
> + * This register resets as unknown in 64bit mode while it resets as zero
> + * in 32bit mode. Here we choose to reset it as zero for consistency.
> + */
> + { Op0(0b11), Op1(0b011), CRn(0b1110), CRm(0b1111), Op2(0b111),
> + access_pmu_evtyper, reset_val, PMCCFILTR_EL0, 0 },
> +
> /* DACR32_EL2 */
> { Op0(0b11), Op1(0b100), CRn(0b0011), CRm(0b0000), Op2(0b000),
> NULL, reset_unknown, DACR32_EL2 },
> @@ -931,6 +1025,13 @@ static const struct sys_reg_desc cp14_64_regs[] = {
> { Op1( 0), CRm( 2), .access = trap_raz_wi },
> };
>
> +/* Macro to expand the PMEVTYPERn register */
> +#define PMU_PMEVTYPER(n) \
> + /* PMEVTYPERn */ \
> + { Op1(0), CRn(0b1110), \
> + CRm((0b1100 | (((n) >> 3) & 0x3))), Op2(((n) & 0x7)), \
> + access_pmu_evtyper }
> +
> /*
> * Trapped cp15 registers. TTBR0/TTBR1 get a double encoding,
> * depending on the way they are accessed (as a 32bit or a 64bit
> @@ -967,7 +1068,7 @@ static const struct sys_reg_desc cp15_regs[] = {
> { Op1( 0), CRn( 9), CRm(12), Op2( 6), access_pmceid },
> { Op1( 0), CRn( 9), CRm(12), Op2( 7), access_pmceid },
> { 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( 1), access_pmu_evtyper },
> { Op1( 0), CRn( 9), CRm(13), Op2( 2), trap_raz_wi },
> { Op1( 0), CRn( 9), CRm(14), Op2( 0), trap_raz_wi },
> { Op1( 0), CRn( 9), CRm(14), Op2( 1), trap_raz_wi },
> @@ -982,6 +1083,41 @@ static const struct sys_reg_desc cp15_regs[] = {
> { Op1( 0), CRn(12), CRm(12), Op2( 5), trap_raz_wi },
>
> { Op1( 0), CRn(13), CRm( 0), Op2( 1), access_vm_reg, NULL, c13_CID },
> +
> + /* PMEVTYPERn */
> + PMU_PMEVTYPER(0),
> + PMU_PMEVTYPER(1),
> + PMU_PMEVTYPER(2),
> + PMU_PMEVTYPER(3),
> + PMU_PMEVTYPER(4),
> + PMU_PMEVTYPER(5),
> + PMU_PMEVTYPER(6),
> + PMU_PMEVTYPER(7),
> + PMU_PMEVTYPER(8),
> + PMU_PMEVTYPER(9),
> + PMU_PMEVTYPER(10),
> + PMU_PMEVTYPER(11),
> + PMU_PMEVTYPER(12),
> + PMU_PMEVTYPER(13),
> + PMU_PMEVTYPER(14),
> + PMU_PMEVTYPER(15),
> + PMU_PMEVTYPER(16),
> + PMU_PMEVTYPER(17),
> + PMU_PMEVTYPER(18),
> + PMU_PMEVTYPER(19),
> + PMU_PMEVTYPER(20),
> + PMU_PMEVTYPER(21),
> + PMU_PMEVTYPER(22),
> + PMU_PMEVTYPER(23),
> + PMU_PMEVTYPER(24),
> + PMU_PMEVTYPER(25),
> + PMU_PMEVTYPER(26),
> + PMU_PMEVTYPER(27),
> + PMU_PMEVTYPER(28),
> + PMU_PMEVTYPER(29),
> + PMU_PMEVTYPER(30),
> + /* PMCCFILTR */
> + { Op1(0), CRn(14), CRm(15), Op2(7), access_pmu_evtyper },
> };
>
> static const struct sys_reg_desc cp15_64_regs[] = {
> --
> 2.0.4
>
>
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