[PATCH v6 1/3] arm64: perf: Include threshold control fields in PMEVTYPER mask

From: James Clark
Date: Fri Nov 24 2023 - 05:31:55 EST


FEAT_PMUv3_TH (Armv8.8) adds two new fields to PMEVTYPER, so include
them in the mask. These aren't writable on 32 bit kernels as they are in
the high part of the register, so only include them for arm64.

It would be difficult to do this statically in the asm header files for
each platform without resulting in circular includes or #ifdefs inline
in the code. For that reason the ARMV8_PMU_EVTYPE_MASK definition has
been removed and the mask is constructed programmatically.

Reviewed-by: Suzuki K Poulose <suzuki.poulose@xxxxxxx>
Reviewed-by: Anshuman Khandual <anshuman.khandual@xxxxxxx>
Signed-off-by: James Clark <james.clark@xxxxxxx>
---
drivers/perf/arm_pmuv3.c | 9 ++++++++-
include/linux/perf/arm_pmuv3.h | 3 ++-
2 files changed, 10 insertions(+), 2 deletions(-)

diff --git a/drivers/perf/arm_pmuv3.c b/drivers/perf/arm_pmuv3.c
index 6ca7be05229c..1d40d794f5e4 100644
--- a/drivers/perf/arm_pmuv3.c
+++ b/drivers/perf/arm_pmuv3.c
@@ -555,8 +555,15 @@ static void armv8pmu_write_counter(struct perf_event *event, u64 value)
static inline void armv8pmu_write_evtype(int idx, u32 val)
{
u32 counter = ARMV8_IDX_TO_COUNTER(idx);
+ unsigned long mask = ARMV8_PMU_EVTYPE_EVENT |
+ ARMV8_PMU_INCLUDE_EL2 |
+ ARMV8_PMU_EXCLUDE_EL0 |
+ ARMV8_PMU_EXCLUDE_EL1;

- val &= ARMV8_PMU_EVTYPE_MASK;
+ if (IS_ENABLED(CONFIG_ARM64))
+ mask |= ARMV8_PMU_EVTYPE_TC | ARMV8_PMU_EVTYPE_TH;
+
+ val &= mask;
write_pmevtypern(counter, val);
}

diff --git a/include/linux/perf/arm_pmuv3.h b/include/linux/perf/arm_pmuv3.h
index 9c226adf938a..ddd1fec86739 100644
--- a/include/linux/perf/arm_pmuv3.h
+++ b/include/linux/perf/arm_pmuv3.h
@@ -228,7 +228,8 @@
/*
* PMXEVTYPER: Event selection reg
*/
-#define ARMV8_PMU_EVTYPE_MASK 0xc800ffff /* Mask for writable bits */
+#define ARMV8_PMU_EVTYPE_TH GENMASK(43, 32)
+#define ARMV8_PMU_EVTYPE_TC GENMASK(63, 61)
#define ARMV8_PMU_EVTYPE_EVENT 0xffff /* Mask for EVENT bits */

/*
--
2.34.1