[PATCH v6 14/21] KVM: ARM64: Add reset and access handlers for PMOVSSET and PMOVSCLR register
Shannon Zhao
zhaoshenglong at huawei.com
Tue Dec 8 04:47:33 PST 2015
From: Shannon Zhao <shannon.zhao at linaro.org>
Since the reset value of PMOVSSET and PMOVSCLR is UNKNOWN, use
reset_unknown for its reset handler. Add a new case to emulate writing
PMOVSSET or PMOVSCLR register.
When writing non-zero value to PMOVSSET, pend PMU interrupt. When the
value writing to PMOVSCLR is equal to the current value, clear the PMU
pending interrupt.
Signed-off-by: Shannon Zhao <shannon.zhao at linaro.org>
---
arch/arm64/kvm/sys_regs.c | 27 ++++++++++++++++--
include/kvm/arm_pmu.h | 4 +++
virt/kvm/arm/pmu.c | 72 +++++++++++++++++++++++++++++++++++++++++++++++
3 files changed, 100 insertions(+), 3 deletions(-)
diff --git a/arch/arm64/kvm/sys_regs.c b/arch/arm64/kvm/sys_regs.c
index c1dffb2..c830fde 100644
--- a/arch/arm64/kvm/sys_regs.c
+++ b/arch/arm64/kvm/sys_regs.c
@@ -601,6 +601,15 @@ static bool access_pmu_regs(struct kvm_vcpu *vcpu,
vcpu_sys_reg(vcpu, r->reg) &= ~p->regval;
break;
}
+ case PMOVSSET_EL0: {
+ if (r->CRm == 14)
+ /* accessing PMOVSSET_EL0 */
+ kvm_pmu_overflow_set(vcpu, p->regval);
+ else
+ /* accessing PMOVSCLR_EL0 */
+ kvm_pmu_overflow_clear(vcpu, p->regval);
+ break;
+ }
case PMCR_EL0: {
/* Only update writeable bits of PMCR */
val = vcpu_sys_reg(vcpu, r->reg);
@@ -847,7 +856,7 @@ static const struct sys_reg_desc sys_reg_descs[] = {
access_pmu_regs, reset_unknown, PMCNTENSET_EL0 },
/* PMOVSCLR_EL0 */
{ Op0(0b11), Op1(0b011), CRn(0b1001), CRm(0b1100), Op2(0b011),
- trap_raz_wi },
+ access_pmu_regs, reset_unknown, PMOVSSET_EL0 },
/* PMSWINC_EL0 */
{ Op0(0b11), Op1(0b011), CRn(0b1001), CRm(0b1100), Op2(0b100),
trap_raz_wi },
@@ -874,7 +883,7 @@ 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_pmu_regs, reset_unknown, PMOVSSET_EL0 },
/* TPIDR_EL0 */
{ Op0(0b11), Op1(0b011), CRn(0b1101), CRm(0b0000), Op2(0b010),
@@ -1184,6 +1193,15 @@ static bool access_pmu_cp15_regs(struct kvm_vcpu *vcpu,
vcpu_cp15(vcpu, r->reg) &= ~p->regval;
break;
}
+ case c9_PMOVSSET: {
+ if (r->CRm == 14)
+ /* accessing c9_PMOVSSET */
+ kvm_pmu_overflow_set(vcpu, p->regval);
+ else
+ /* accessing c9_PMOVSCLR */
+ kvm_pmu_overflow_clear(vcpu, p->regval);
+ break;
+ }
case c9_PMCR: {
/* Only update writeable bits of PMCR */
val = vcpu_cp15(vcpu, r->reg);
@@ -1271,7 +1289,8 @@ static const struct sys_reg_desc cp15_regs[] = {
NULL, c9_PMCNTENSET },
{ Op1( 0), CRn( 9), CRm(12), Op2( 2), access_pmu_cp15_regs,
NULL, c9_PMCNTENSET },
- { Op1( 0), CRn( 9), CRm(12), Op2( 3), trap_raz_wi },
+ { Op1( 0), CRn( 9), CRm(12), Op2( 3), access_pmu_cp15_regs,
+ NULL, c9_PMOVSSET },
{ Op1( 0), CRn( 9), CRm(12), Op2( 5), access_pmu_cp15_regs,
NULL, c9_PMSELR },
{ Op1( 0), CRn( 9), CRm(12), Op2( 6), access_pmu_cp15_regs,
@@ -1287,6 +1306,8 @@ static const struct sys_reg_desc cp15_regs[] = {
NULL, c9_PMINTENSET },
{ Op1( 0), CRn( 9), CRm(14), Op2( 2), access_pmu_cp15_regs,
NULL, c9_PMINTENSET },
+ { Op1( 0), CRn( 9), CRm(14), Op2( 3), access_pmu_cp15_regs,
+ NULL, c9_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 e731656..a76df52 100644
--- a/include/kvm/arm_pmu.h
+++ b/include/kvm/arm_pmu.h
@@ -41,6 +41,8 @@ struct kvm_pmu {
u64 kvm_pmu_get_counter_value(struct kvm_vcpu *vcpu, u32 select_idx);
void kvm_pmu_disable_counter(struct kvm_vcpu *vcpu, u32 val);
void kvm_pmu_enable_counter(struct kvm_vcpu *vcpu, u32 val, bool all_enable);
+void kvm_pmu_overflow_clear(struct kvm_vcpu *vcpu, u32 val);
+void kvm_pmu_overflow_set(struct kvm_vcpu *vcpu, u32 val);
void kvm_pmu_set_counter_event_type(struct kvm_vcpu *vcpu, u32 data,
u32 select_idx);
#else
@@ -50,6 +52,8 @@ u64 kvm_pmu_get_counter_value(struct kvm_vcpu *vcpu, u32 select_idx)
}
void kvm_pmu_disable_counter(struct kvm_vcpu *vcpu, u32 val) {}
void kvm_pmu_enable_counter(struct kvm_vcpu *vcpu, u32 val, bool all_enable) {}
+void kvm_pmu_overflow_clear(struct kvm_vcpu *vcpu, u32 val) {}
+void kvm_pmu_overflow_set(struct kvm_vcpu *vcpu, u32 val) {}
void kvm_pmu_set_counter_event_type(struct kvm_vcpu *vcpu, u32 data,
u32 select_idx) {}
#endif
diff --git a/virt/kvm/arm/pmu.c b/virt/kvm/arm/pmu.c
index 45586d2..ba7d11c 100644
--- a/virt/kvm/arm/pmu.c
+++ b/virt/kvm/arm/pmu.c
@@ -136,6 +136,78 @@ void kvm_pmu_disable_counter(struct kvm_vcpu *vcpu, u32 val)
}
}
+static u32 kvm_pmu_valid_counter_mask(struct kvm_vcpu *vcpu)
+{
+ u32 val;
+
+ if (!vcpu_mode_is_32bit(vcpu))
+ val = (vcpu_sys_reg(vcpu, PMCR_EL0) >> ARMV8_PMCR_N_SHIFT)
+ & ARMV8_PMCR_N_MASK;
+ else
+ val = (vcpu_cp15(vcpu, c9_PMCR) >> ARMV8_PMCR_N_SHIFT)
+ & ARMV8_PMCR_N_MASK;
+
+ return GENMASK(val - 1, 0) | BIT(ARMV8_COUNTER_MASK);
+}
+
+/**
+ * kvm_pmu_overflow_clear - clear PMU overflow interrupt
+ * @vcpu: The vcpu pointer
+ * @val: the value guest writes to PMOVSCLR register
+ * @reg: the current value of PMOVSCLR register
+ */
+void kvm_pmu_overflow_clear(struct kvm_vcpu *vcpu, u32 val)
+{
+ u32 mask = kvm_pmu_valid_counter_mask(vcpu);
+
+ if (!vcpu_mode_is_32bit(vcpu)) {
+ vcpu_sys_reg(vcpu, PMOVSSET_EL0) &= mask;
+ vcpu_sys_reg(vcpu, PMOVSSET_EL0) &= ~val;
+ val = vcpu_sys_reg(vcpu, PMOVSSET_EL0);
+ } else {
+ vcpu_cp15(vcpu, c9_PMOVSSET) &= mask;
+ vcpu_cp15(vcpu, c9_PMOVSSET) &= ~val;
+ val = vcpu_cp15(vcpu, c9_PMOVSSET);
+ }
+
+ /* If all overflow bits are cleared, kick the vcpu to clear interrupt
+ * pending status.
+ */
+ if (val == 0)
+ kvm_vcpu_kick(vcpu);
+}
+
+/**
+ * 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, u32 val)
+{
+ u32 mask = kvm_pmu_valid_counter_mask(vcpu);
+
+ val &= mask;
+ if (val == 0)
+ return;
+
+ if (!vcpu_mode_is_32bit(vcpu)) {
+ vcpu_sys_reg(vcpu, PMOVSSET_EL0) &= mask;
+ vcpu_sys_reg(vcpu, PMOVSSET_EL0) |= val;
+ val = vcpu_sys_reg(vcpu, PMCNTENSET_EL0)
+ & vcpu_sys_reg(vcpu, PMINTENSET_EL1)
+ & vcpu_sys_reg(vcpu, PMOVSSET_EL0);
+ } else {
+ vcpu_cp15(vcpu, c9_PMOVSSET) &= mask;
+ vcpu_cp15(vcpu, c9_PMOVSSET) |= val;
+ val = vcpu_cp15(vcpu, c9_PMCNTENSET)
+ & vcpu_cp15(vcpu, c9_PMINTENSET)
+ & vcpu_cp15(vcpu, c9_PMOVSSET);
+ }
+
+ if (val != 0)
+ kvm_vcpu_kick(vcpu);
+}
+
/**
* kvm_pmu_set_counter_event_type - set selected counter to monitor some event
* @vcpu: The vcpu pointer
--
2.0.4
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