Messages in this thread Patch in this message | | | From | Srinivasarao Pathipati <> | Subject | [PATCH V2] arm64: perf: Retain PMCR.X of PMCR_EL0 during reset | Date | Fri, 29 Apr 2022 16:59:09 +0530 |
| |
Preserve the bit PMCR.X of PMCR_EL0 during PMU reset to export PMU events. as it could be set before PMU initialization.
Signed-off-by: Srinivasarao Pathipati <quic_c_spathi@quicinc.com> --- Changes since V1: - Preserving only PMCR_X bit as per Robin Murphy's comment --- arch/arm64/kernel/perf_event.c | 3 +++ 1 file changed, 3 insertions(+)
diff --git a/arch/arm64/kernel/perf_event.c b/arch/arm64/kernel/perf_event.c index cb69ff1..532a417 100644 --- a/arch/arm64/kernel/perf_event.c +++ b/arch/arm64/kernel/perf_event.c @@ -1047,6 +1047,9 @@ static void armv8pmu_reset(void *info) if (armv8pmu_has_long_event(cpu_pmu)) pmcr |= ARMV8_PMU_PMCR_LP; + /* Preserve PMCR_X to export PMU events */ + pmcr |= (armv8pmu_pmcr_read() & ARMV8_PMU_PMCR_X); + armv8pmu_pmcr_write(pmcr); } -- 2.7.4
| |