[PATCH v7 09/19] KVM: ARM64: Add access handler for event counter register

Shannon Zhao
2015-12-15T08:49:29Z

From: Shannon Zhao <shannon.zhao@linaro.org>

These kind of registers include PMEVCNTRn, PMCCNTR and PMXEVCNTR which
is mapped to PMEVCNTRn.

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 reading these registers, return the sum of register value and the
value perf event counts.

Signed-off-by: Shannon Zhao <shannon.zhao@linaro.org>
---
arch/arm64/kvm/sys_regs.c | 136 ++++++++++++++++++++++++++++++++++++++++++++--
1 file changed, 132 insertions(+), 4 deletions(-)

diff --git a/arch/arm64/kvm/sys_regs.c b/arch/arm64/kvm/sys_regs.c
index c52ff15..dc6bb26 100644
--- a/arch/arm64/kvm/sys_regs.c
+++ b/arch/arm64/kvm/sys_regs.c
@@ -566,6 +566,55 @@ static bool access_pmu_evtyper(struct kvm_vcpu *vcpu, struct sys_reg_params *p,
return true;
}

+static bool access_pmu_evcntr(struct kvm_vcpu *vcpu,
+ struct sys_reg_params *p,
+ const struct sys_reg_desc *r)
+{
+ u64 idx, reg, val;
+
+ if (!p->is_aarch32) {
+ if (r->CRn == 9 && r->CRm == 13 && r->Op2 == 2)
+ /* PMXEVCNTR_EL0 */
+ reg = 0;
+ else
+ /* PMEVCNTRn_EL0 or PMCCNTR_EL0 */
+ reg = r->reg;
+ } else {
+ if (r->CRn == 9 && r->CRm == 13) {
+ reg = (r->Op2 & 2) ? 0 : PMCCNTR_EL0;
+ } else {
+ reg = ((r->CRm & 3) << 3) & (r->Op2 & 7);
+ reg += PMEVCNTR0_EL0;
+ }
+ }
+
+ switch (reg) {
+ case PMEVCNTR0_EL0 ... PMEVCNTR30_EL0:
+ idx = reg - PMEVCNTR0_EL0;
+ break;
+ case PMCCNTR_EL0:
+ idx = ARMV8_CYCLE_IDX;
+ break;
+ default:
+ /* PMXEVCNTR_EL0 */
+ idx = vcpu_sys_reg(vcpu, PMSELR_EL0) & ARMV8_COUNTER_MASK;
+ if (!pmu_counter_idx_valid(vcpu, idx))
+ return true;
+
+ reg = (idx == ARMV8_CYCLE_IDX) ? PMCCNTR_EL0
+ : PMEVCNTR0_EL0 + idx;
+ break;
+ }
+
+ val = kvm_pmu_get_counter_value(vcpu, idx);
+ if (p->is_write)
+ vcpu_sys_reg(vcpu, reg) += (s64)p->regval - val;
+ else
+ p->regval = val;
+
+ 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 */ \
@@ -581,6 +630,13 @@ static bool access_pmu_evtyper(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 PMEVCNTRn_EL0 register */
+#define PMU_PMEVCNTR_EL0(n) \
+ /* PMEVCNTRn_EL0 */ \
+ { Op0(0b11), Op1(0b011), CRn(0b1110), \
+ CRm((0b1000 | (((n) >> 3) & 0x3))), Op2(((n) & 0x7)), \
+ access_pmu_evcntr, reset_unknown, (PMEVCNTR0_EL0 + n), }
+
/* Macro to expand the PMEVTYPERn_EL0 register */
#define PMU_PMEVTYPER_EL0(n) \
/* PMEVTYPERn_EL0 */ \
@@ -781,13 +837,13 @@ static const struct sys_reg_desc sys_reg_descs[] = {
access_pmceid },
/* PMCCNTR_EL0 */
{ Op0(0b11), Op1(0b011), CRn(0b1001), CRm(0b1101), Op2(0b000),
- trap_raz_wi },
+ access_pmu_evcntr, reset_unknown, PMCCNTR_EL0 },
/* PMXEVTYPER_EL0 */
{ Op0(0b11), Op1(0b011), CRn(0b1001), CRm(0b1101), Op2(0b001),
access_pmu_evtyper },
/* PMXEVCNTR_EL0 */
{ Op0(0b11), Op1(0b011), CRn(0b1001), CRm(0b1101), Op2(0b010),
- trap_raz_wi },
+ access_pmu_evcntr },
/* PMUSERENR_EL0 */
{ Op0(0b11), Op1(0b011), CRn(0b1001), CRm(0b1110), Op2(0b000),
trap_raz_wi },
@@ -802,6 +858,38 @@ static const struct sys_reg_desc sys_reg_descs[] = {
{ Op0(0b11), Op1(0b011), CRn(0b1101), CRm(0b0000), Op2(0b011),
NULL, reset_unknown, TPIDRRO_EL0 },

+ /* PMEVCNTRn_EL0 */
+ PMU_PMEVCNTR_EL0(0),
+ PMU_PMEVCNTR_EL0(1),
+ PMU_PMEVCNTR_EL0(2),
+ PMU_PMEVCNTR_EL0(3),
+ PMU_PMEVCNTR_EL0(4),
+ PMU_PMEVCNTR_EL0(5),
+ PMU_PMEVCNTR_EL0(6),
+ PMU_PMEVCNTR_EL0(7),
+ PMU_PMEVCNTR_EL0(8),
+ PMU_PMEVCNTR_EL0(9),
+ PMU_PMEVCNTR_EL0(10),
+ PMU_PMEVCNTR_EL0(11),
+ PMU_PMEVCNTR_EL0(12),
+ PMU_PMEVCNTR_EL0(13),
+ PMU_PMEVCNTR_EL0(14),
+ PMU_PMEVCNTR_EL0(15),
+ PMU_PMEVCNTR_EL0(16),
+ PMU_PMEVCNTR_EL0(17),
+ PMU_PMEVCNTR_EL0(18),
+ PMU_PMEVCNTR_EL0(19),
+ PMU_PMEVCNTR_EL0(20),
+ PMU_PMEVCNTR_EL0(21),
+ PMU_PMEVCNTR_EL0(22),
+ PMU_PMEVCNTR_EL0(23),
+ PMU_PMEVCNTR_EL0(24),
+ PMU_PMEVCNTR_EL0(25),
+ PMU_PMEVCNTR_EL0(26),
+ PMU_PMEVCNTR_EL0(27),
+ PMU_PMEVCNTR_EL0(28),
+ PMU_PMEVCNTR_EL0(29),
+ PMU_PMEVCNTR_EL0(30),
/* PMEVTYPERn_EL0 */
PMU_PMEVTYPER_EL0(0),
PMU_PMEVTYPER_EL0(1),
@@ -1030,6 +1118,13 @@ static const struct sys_reg_desc cp14_64_regs[] = {
{ Op1( 0), CRm( 2), .access = trap_raz_wi },
};

+/* Macro to expand the PMEVCNTRn register */
+#define PMU_PMEVCNTR(n) \
+ /* PMEVCNTRn */ \
+ { Op1(0), CRn(0b1110), \
+ CRm((0b1000 | (((n) >> 3) & 0x3))), Op2(((n) & 0x7)), \
+ access_pmu_evcntr }
+
/* Macro to expand the PMEVTYPERn register */
#define PMU_PMEVTYPER(n) \
/* PMEVTYPERn */ \
@@ -1072,9 +1167,9 @@ static const struct sys_reg_desc cp15_regs[] = {
{ 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 },
- { Op1( 0), CRn( 9), CRm(13), Op2( 0), trap_raz_wi },
+ { Op1( 0), CRn( 9), CRm(13), Op2( 0), access_pmu_evcntr },
{ 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(13), Op2( 2), access_pmu_evcntr },
{ Op1( 0), CRn( 9), CRm(14), Op2( 0), trap_raz_wi },
{ Op1( 0), CRn( 9), CRm(14), Op2( 1), trap_raz_wi },
{ Op1( 0), CRn( 9), CRm(14), Op2( 2), trap_raz_wi },
@@ -1089,6 +1184,38 @@ static const struct sys_reg_desc cp15_regs[] = {

{ Op1( 0), CRn(13), CRm( 0), Op2( 1), access_vm_reg, NULL, c13_CID },

+ /* PMEVCNTRn */
+ PMU_PMEVCNTR(0),
+ PMU_PMEVCNTR(1),
+ PMU_PMEVCNTR(2),
+ PMU_PMEVCNTR(3),
+ PMU_PMEVCNTR(4),
+ PMU_PMEVCNTR(5),
+ PMU_PMEVCNTR(6),
+ PMU_PMEVCNTR(7),
+ PMU_PMEVCNTR(8),
+ PMU_PMEVCNTR(9),
+ PMU_PMEVCNTR(10),
+ PMU_PMEVCNTR(11),
+ PMU_PMEVCNTR(12),
+ PMU_PMEVCNTR(13),
+ PMU_PMEVCNTR(14),
+ PMU_PMEVCNTR(15),
+ PMU_PMEVCNTR(16),
+ PMU_PMEVCNTR(17),
+ PMU_PMEVCNTR(18),
+ PMU_PMEVCNTR(19),
+ PMU_PMEVCNTR(20),
+ PMU_PMEVCNTR(21),
+ PMU_PMEVCNTR(22),
+ PMU_PMEVCNTR(23),
+ PMU_PMEVCNTR(24),
+ PMU_PMEVCNTR(25),
+ PMU_PMEVCNTR(26),
+ PMU_PMEVCNTR(27),
+ PMU_PMEVCNTR(28),
+ PMU_PMEVCNTR(29),
+ PMU_PMEVCNTR(30),
/* PMEVTYPERn */
PMU_PMEVTYPER(0),
PMU_PMEVTYPER(1),
@@ -1127,6 +1254,7 @@ static const struct sys_reg_desc cp15_regs[] = {

static const struct sys_reg_desc cp15_64_regs[] = {
{ Op1( 0), CRn( 0), CRm( 2), Op2( 0), access_vm_reg, NULL, c2_TTBR0 },
+ { Op1( 0), CRn( 0), CRm( 9), Op2( 0), access_pmu_evcntr },
{ Op1( 0), CRn( 0), CRm(12), Op2( 0), access_gic_sgi },
{ Op1( 1), CRn( 0), CRm( 2), Op2( 0), access_vm_reg, NULL, c2_TTBR1 },
};
--
2.0.4