[PATCH 1/2] RISC-V: Fix counter restart during overflow for RV32

Atish Patra atishp at rivosinc.com
Wed May 11 13:11:06 PDT 2022


Pass the upper half of the initial value of the counter correctly
for RV32.

Fixes: 4905ec2fb7e6 ("RISC-V: Add sscofpmf extension support")

Signed-off-by: Atish Patra <atishp at rivosinc.com>
---
 drivers/perf/riscv_pmu_sbi.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/perf/riscv_pmu_sbi.c b/drivers/perf/riscv_pmu_sbi.c
index a1317a483512..24cea59612be 100644
--- a/drivers/perf/riscv_pmu_sbi.c
+++ b/drivers/perf/riscv_pmu_sbi.c
@@ -526,7 +526,7 @@ static inline void pmu_sbi_start_overflow_mask(struct riscv_pmu *pmu,
 			max_period = riscv_pmu_ctr_get_width_mask(event);
 			init_val = local64_read(&hwc->prev_count) & max_period;
 			sbi_ecall(SBI_EXT_PMU, SBI_EXT_PMU_COUNTER_START, idx, 1,
-				  flag, init_val, 0, 0);
+				  flag, init_val, init_val >> 32, 0);
 		}
 		ctr_ovf_mask = ctr_ovf_mask >> 1;
 		idx++;
-- 
2.25.1




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