| Message ID | 20190322162333.17159-3-drjones@redhat.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | target/arm: pmu fixes | expand |
On Mar 22 17:23, Andrew Jones wrote: > cortex-a7 and cortex-a15 have pmus (PMUv2) and they advertise > them in ID_DFR0. Let's allow them to function. This also enables > the pmu cpu property to work with these cpu types, i.e. we can > now do '-cpu cortex-a15,pmu=off' to remove the pmu. I'm a little nervous about this one, but PMUv2 isn't fresh enough in my mind to have a good reason other than that I didn't consider it when writing my recent PMU patches. Do you know if this boots a kernel that can detect and use the PMU successfully while thinking it's PMUv2? -Aaron > Signed-off-by: Andrew Jones <drjones@redhat.com> > --- > target/arm/cpu.c | 3 +++ > 1 file changed, 3 insertions(+) > > diff --git a/target/arm/cpu.c b/target/arm/cpu.c > index 96f0ff0ec727..504a4771fbd3 100644 > --- a/target/arm/cpu.c > +++ b/target/arm/cpu.c > @@ -1109,6 +1109,7 @@ static void arm_cpu_realizefn(DeviceState *dev, Error **errp) > #endif > } else { > cpu->id_aa64dfr0 &= ~0xf00; > + cpu->id_dfr0 &= ~(0xf << 24); > cpu->pmceid0 = 0; > cpu->pmceid1 = 0; > } > @@ -1744,6 +1745,7 @@ static void cortex_a7_initfn(Object *obj) > set_feature(&cpu->env, ARM_FEATURE_CBAR_RO); > set_feature(&cpu->env, ARM_FEATURE_EL2); > set_feature(&cpu->env, ARM_FEATURE_EL3); > + set_feature(&cpu->env, ARM_FEATURE_PMU); > cpu->kvm_target = QEMU_KVM_ARM_TARGET_CORTEX_A7; > cpu->midr = 0x410fc075; > cpu->reset_fpsid = 0x41023075; > @@ -1789,6 +1791,7 @@ static void cortex_a15_initfn(Object *obj) > set_feature(&cpu->env, ARM_FEATURE_CBAR_RO); > set_feature(&cpu->env, ARM_FEATURE_EL2); > set_feature(&cpu->env, ARM_FEATURE_EL3); > + set_feature(&cpu->env, ARM_FEATURE_PMU); > cpu->kvm_target = QEMU_KVM_ARM_TARGET_CORTEX_A15; > cpu->midr = 0x412fc0f1; > cpu->reset_fpsid = 0x410430f0; > -- > 2.17.2 >
On Tue, Mar 26, 2019 at 05:38:36PM +0000, Aaron Lindsay OS wrote: > On Mar 22 17:23, Andrew Jones wrote: > > cortex-a7 and cortex-a15 have pmus (PMUv2) and they advertise > > them in ID_DFR0. Let's allow them to function. This also enables > > the pmu cpu property to work with these cpu types, i.e. we can > > now do '-cpu cortex-a15,pmu=off' to remove the pmu. > > I'm a little nervous about this one, but PMUv2 isn't fresh enough in my > mind to have a good reason other than that I didn't consider it when > writing my recent PMU patches. Do you know if this boots a kernel that > can detect and use the PMU successfully while thinking it's PMUv2? > I didn't try booting a kernel and running perf or anything like that. It does now run the pmu kvm-unit-tests test though. As this patch is now in master the test you propose can be done with a latest build :) Thanks, drew
diff --git a/target/arm/cpu.c b/target/arm/cpu.c index 96f0ff0ec727..504a4771fbd3 100644 --- a/target/arm/cpu.c +++ b/target/arm/cpu.c @@ -1109,6 +1109,7 @@ static void arm_cpu_realizefn(DeviceState *dev, Error **errp) #endif } else { cpu->id_aa64dfr0 &= ~0xf00; + cpu->id_dfr0 &= ~(0xf << 24); cpu->pmceid0 = 0; cpu->pmceid1 = 0; } @@ -1744,6 +1745,7 @@ static void cortex_a7_initfn(Object *obj) set_feature(&cpu->env, ARM_FEATURE_CBAR_RO); set_feature(&cpu->env, ARM_FEATURE_EL2); set_feature(&cpu->env, ARM_FEATURE_EL3); + set_feature(&cpu->env, ARM_FEATURE_PMU); cpu->kvm_target = QEMU_KVM_ARM_TARGET_CORTEX_A7; cpu->midr = 0x410fc075; cpu->reset_fpsid = 0x41023075; @@ -1789,6 +1791,7 @@ static void cortex_a15_initfn(Object *obj) set_feature(&cpu->env, ARM_FEATURE_CBAR_RO); set_feature(&cpu->env, ARM_FEATURE_EL2); set_feature(&cpu->env, ARM_FEATURE_EL3); + set_feature(&cpu->env, ARM_FEATURE_PMU); cpu->kvm_target = QEMU_KVM_ARM_TARGET_CORTEX_A15; cpu->midr = 0x412fc0f1; cpu->reset_fpsid = 0x410430f0;
cortex-a7 and cortex-a15 have pmus (PMUv2) and they advertise them in ID_DFR0. Let's allow them to function. This also enables the pmu cpu property to work with these cpu types, i.e. we can now do '-cpu cortex-a15,pmu=off' to remove the pmu. Signed-off-by: Andrew Jones <drjones@redhat.com> --- target/arm/cpu.c | 3 +++ 1 file changed, 3 insertions(+)