[v5] target/arm: Always add pmu property for Armv7-A/R+

Commit Message

Akihiko Odaki Jan. 4, 2025, 7:10 a.m. UTC

kvm-steal-time and sve properties are added for KVM even if the
corresponding features are not available. Always add pmu property for
Armv7+. Note that the property is added only for Armv7-A/R+ as QEMU
currently emulates PMU only for such versions, and a different
version may have a different definition of PMU or may not have one at
all.

Signed-off-by: Akihiko Odaki <[e-mail]>
---
The "pmu" property is added only when the PMU is available. This makes
tests/qtest/arm-cpu-features.c fail as it reads the property to check
the availability. Always add the property when the architecture defines
the PMU even if it's not available to fix this.
---
Changes in v5:
- Rebased.
- Link to v4: https://lore.kernel.org/r/[e-mail]

Changes in v4:
- Split patch "target/arm/kvm: Fix PMU feature bit early" into
  "target/arm/kvm: Set PMU for host only when available" and
  "target/arm/kvm: Do not silently remove PMU".
- Changed to define PMU also for Armv7.
- Changed not to define PMU for M.
- Extracted patch "hvf: arm: Raise an exception for sysreg by default"
  from "hvf: arm: Properly disable PMU".
- Rebased.
- Link to v3: https://lore.kernel.org/r/[e-mail]

Changes in v3:
- Dropped patch "target/arm: Do not allow setting 'pmu' for hvf".
- Dropped patch "target/arm: Allow setting 'pmu' only for host and max".
- Dropped patch "target/arm/kvm: Report PMU unavailability".
- Added patch "target/arm/kvm: Fix PMU feature bit early".
- Added patch "hvf: arm: Do not advance PC when raising an exception".
- Added patch "hvf: arm: Properly disable PMU".
- Changed to check for Armv8 before adding PMU property.
- Link to v2: https://lore.kernel.org/r/[e-mail]

Changes in v2:
- Restricted writes to 'pmu' to host and max.
- Prohibited writes to 'pmu' for hvf.
- Link to v1: https://lore.kernel.org/r/[e-mail]
---
 target/arm/cpu.c | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)


---
base-commit: 38d0939b86e2eef6f6a622c6f1f7befda0146595
change-id: 20240629-pmu-ad5f67e2c5d0

Best regards,

Patch

diff --git a/target/arm/cpu.c b/target/arm/cpu.c
index dcedadc89eaf..e76d42398eb2 100644
--- a/target/arm/cpu.c
+++ b/target/arm/cpu.c
@@ -1761,6 +1761,10 @@  void arm_cpu_post_init(Object *obj)
 
     if (!arm_feature(&cpu->env, ARM_FEATURE_M)) {
         qdev_property_add_static(DEVICE(obj), &arm_cpu_reset_hivecs_property);
+
+        if (arm_feature(&cpu->env, ARM_FEATURE_V7)) {
+            object_property_add_bool(obj, "pmu", arm_get_pmu, arm_set_pmu);
+        }
     }
 
     if (arm_feature(&cpu->env, ARM_FEATURE_V8)) {
@@ -1790,7 +1794,6 @@  void arm_cpu_post_init(Object *obj)
 
     if (arm_feature(&cpu->env, ARM_FEATURE_PMU)) {
         cpu->has_pmu = true;
-        object_property_add_bool(obj, "pmu", arm_get_pmu, arm_set_pmu);
     }
 
     /*