On 01/12/2021 22.49, Marc Zyngier wrote:
The current ARM PMU framework can only deal with 32 or 64bit counters.
Teach it about a 47bit flavour.
Yes, this is odd.
Signed-off-by: Marc Zyngier <maz@xxxxxxxxxx>
---
drivers/perf/arm_pmu.c | 2 ++
include/linux/perf/arm_pmu.h | 2 ++
2 files changed, 4 insertions(+)
diff --git a/drivers/perf/arm_pmu.c b/drivers/perf/arm_pmu.c
index 295cc7952d0e..0a9ed1a061ac 100644
--- a/drivers/perf/arm_pmu.c
+++ b/drivers/perf/arm_pmu.c
@@ -109,6 +109,8 @@ static inline u64 arm_pmu_event_max_period(struct perf_event *event)
{
if (event->hw.flags & ARMPMU_EVT_64BIT)
return GENMASK_ULL(63, 0);
+ else if (event->hw.flags & ARMPMU_EVT_47BIT)
+ return GENMASK_ULL(46, 0);
else
return GENMASK_ULL(31, 0);
}
diff --git a/include/linux/perf/arm_pmu.h b/include/linux/perf/arm_pmu.h
index 2512e2f9cd4e..0407a38b470a 100644
--- a/include/linux/perf/arm_pmu.h
+++ b/include/linux/perf/arm_pmu.h
@@ -26,6 +26,8 @@
*/
/* Event uses a 64bit counter */
#define ARMPMU_EVT_64BIT 1
+/* Event uses a 47bit counter */
+#define ARMPMU_EVT_47BIT 2
#define HW_OP_UNSUPPORTED 0xFFFF
#define C(_x) PERF_COUNT_HW_CACHE_##_x
Reviewed-by: Hector Martin <marcan@xxxxxxxxx>
--
Hector Martin (marcan@xxxxxxxxx)
Public Key: https://mrcn.st/pub
