[PATCH v2 3/3] RISC-V: Fix SBI PMU calls for RV32

Atish Patra atishp at rivosinc.com
Thu May 12 18:55:22 PDT 2022


Some of the SBI PMU calls does not pass 64bit arguments
correctly and not under RV32 compile time flags. Currently,
this doesn't create any incorrect results as RV64 ignores
any value in the additional register and qemu doesn't support
raw events.

Fix those SBI calls in order to set correct values for RV32.

Fixes: e9991434596f ("RISC-V: Add perf platform driver based on SBI PMU extension")

Signed-off-by: Atish Patra <atishp at rivosinc.com>
---
 drivers/perf/riscv_pmu_sbi.c | 10 ++++++++++
 1 file changed, 10 insertions(+)

diff --git a/drivers/perf/riscv_pmu_sbi.c b/drivers/perf/riscv_pmu_sbi.c
index 7ad92039a718..fab0dd497393 100644
--- a/drivers/perf/riscv_pmu_sbi.c
+++ b/drivers/perf/riscv_pmu_sbi.c
@@ -274,8 +274,13 @@ static int pmu_sbi_ctr_get_idx(struct perf_event *event)
 		cflags |= SBI_PMU_CFG_FLAG_SET_UINH;
 
 	/* retrieve the available counter index */
+#if defined(CONFIG_32BIT)
+	ret = sbi_ecall(SBI_EXT_PMU, SBI_EXT_PMU_COUNTER_CFG_MATCH, cbase, cmask,
+			cflags, hwc->event_base, hwc->config, hwc->config >> 32);
+#else
 	ret = sbi_ecall(SBI_EXT_PMU, SBI_EXT_PMU_COUNTER_CFG_MATCH, cbase, cmask,
 			cflags, hwc->event_base, hwc->config, 0);
+#endif
 	if (ret.error) {
 		pr_debug("Not able to find a counter for event %lx config %llx\n",
 			hwc->event_base, hwc->config);
@@ -417,8 +422,13 @@ static void pmu_sbi_ctr_start(struct perf_event *event, u64 ival)
 	struct hw_perf_event *hwc = &event->hw;
 	unsigned long flag = SBI_PMU_START_FLAG_SET_INIT_VALUE;
 
+#if defined(CONFIG_32BIT)
 	ret = sbi_ecall(SBI_EXT_PMU, SBI_EXT_PMU_COUNTER_START, hwc->idx,
 			1, flag, ival, ival >> 32, 0);
+#else
+	ret = sbi_ecall(SBI_EXT_PMU, SBI_EXT_PMU_COUNTER_START, hwc->idx,
+			1, flag, ival, 0, 0);
+#endif
 	if (ret.error && (ret.error != SBI_ERR_ALREADY_STARTED))
 		pr_err("Starting counter idx %d failed with error %d\n",
 			hwc->idx, sbi_err_map_linux_errno(ret.error));
-- 
2.25.1




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