[PATCH v6 06/21] KVM: ARM64: Add reset and access handlers for PMCEID0 and PMCEID1 register

[Shannon Zhao]

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 d81f7ac..1bcb2b7 100644
--- a/arch/arm64/kvm/sys_regs.c
+++ b/arch/arm64/kvm/sys_regs.c
@@ -452,6 +452,19 @@ static void reset_pmcr(struct kvm_vcpu *vcpu, const struct sys_reg_desc *r)
 	vcpu_sys_reg(vcpu, r->reg) = val;
 }
 
+static void reset_pmceid(struct kvm_vcpu *vcpu, const struct sys_reg_desc *r)
+{
+	u64 pmceid;
+
+	if (r->reg == PMCEID0_EL0)
+		asm volatile("mrs %0, pmceid0_el0\n" : "=r" (pmceid));
+	else
+		/* PMCEID1_EL0 */
+		asm volatile("mrs %0, pmceid1_el0\n" : "=r" (pmceid));
+
+	vcpu_sys_reg(vcpu, r->reg) = pmceid;
+}
+
 /* PMU registers accessor. */
 static bool access_pmu_regs(struct kvm_vcpu *vcpu,
 			    struct sys_reg_params *p,
@@ -469,6 +482,9 @@ 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) = p->regval;
 			break;
@@ -693,10 +709,10 @@ 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 },
@@ -926,6 +942,9 @@ 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) = p->regval;
 			break;
@@ -983,8 +1002,10 @@ 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,
 	  NULL, 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,
+	  NULL, c9_PMCEID0 },
+	{ Op1( 0), CRn( 9), CRm(12), Op2( 7), access_pmu_cp15_regs,
+	  NULL, c9_PMCEID1 },
 	{ 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 },
-- 
2.0.4