[PATCH 5.19 0077/1157] RISC-V: Fix counter restart during overflow for RV32

From: Greg Kroah-Hartman
Date: Mon Aug 15 2022 - 18:08:18 EST


From: Atish Patra <atishp@xxxxxxxxxxxx>

commit acc1b919f47926b089be21b8aaa29ec91fef0aa2 upstream.

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@xxxxxxxxxxxx>
Reviewed-by: Guo Ren <guoren@xxxxxxxxxx>
Cc: stable@xxxxxxxxxxxxxxx
Link: https://lore.kernel.org/r/20220711174632.4186047-2-atishp@xxxxxxxxxxxx
Signed-off-by: Palmer Dabbelt <palmer@xxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/perf/riscv_pmu_sbi.c | 5 +++++
1 file changed, 5 insertions(+)

--- a/drivers/perf/riscv_pmu_sbi.c
+++ b/drivers/perf/riscv_pmu_sbi.c
@@ -525,8 +525,13 @@ static inline void pmu_sbi_start_overflo
hwc = &event->hw;
max_period = riscv_pmu_ctr_get_width_mask(event);
init_val = local64_read(&hwc->prev_count) & max_period;
+#if defined(CONFIG_32BIT)
+ sbi_ecall(SBI_EXT_PMU, SBI_EXT_PMU_COUNTER_START, idx, 1,
+ flag, init_val, init_val >> 32, 0);
+#else
sbi_ecall(SBI_EXT_PMU, SBI_EXT_PMU_COUNTER_START, idx, 1,
flag, init_val, 0, 0);
+#endif
}
ctr_ovf_mask = ctr_ovf_mask >> 1;
idx++;