[PATCH] perf: RISC-V: fix IRQ detection on T-Head C908

Qingfang Deng dqfext at gmail.com
Sun Mar 10 23:30:18 PDT 2024


T-Head C908 has the same IRQ num and CSR as previous C9xx cores, but
reports non-zero marchid and mimpid. Remove the ID checks.

Fixes: 65e9fb081877 ("drivers/perf: riscv_pmu_sbi: add support for PMU variant on T-Head C9xx cores")
Signed-off-by: Qingfang Deng <dqfext at gmail.com>
---
 arch/riscv/errata/thead/errata.c | 4 ----
 drivers/perf/riscv_pmu_sbi.c     | 4 +---
 2 files changed, 1 insertion(+), 7 deletions(-)

diff --git a/arch/riscv/errata/thead/errata.c b/arch/riscv/errata/thead/errata.c
index b1c410bbc1ae..49ccad5b21bb 100644
--- a/arch/riscv/errata/thead/errata.c
+++ b/arch/riscv/errata/thead/errata.c
@@ -125,10 +125,6 @@ static bool errata_probe_pmu(unsigned int stage,
 	if (!IS_ENABLED(CONFIG_ERRATA_THEAD_PMU))
 		return false;
 
-	/* target-c9xx cores report arch_id and impid as 0 */
-	if (arch_id != 0 || impid != 0)
-		return false;
-
 	if (stage == RISCV_ALTERNATIVES_EARLY_BOOT)
 		return false;
 
diff --git a/drivers/perf/riscv_pmu_sbi.c b/drivers/perf/riscv_pmu_sbi.c
index 452aab49db1e..87b83184383a 100644
--- a/drivers/perf/riscv_pmu_sbi.c
+++ b/drivers/perf/riscv_pmu_sbi.c
@@ -811,9 +811,7 @@ static int pmu_sbi_setup_irqs(struct riscv_pmu *pmu, struct platform_device *pde
 		riscv_pmu_irq_num = RV_IRQ_PMU;
 		riscv_pmu_use_irq = true;
 	} else if (IS_ENABLED(CONFIG_ERRATA_THEAD_PMU) &&
-		   riscv_cached_mvendorid(0) == THEAD_VENDOR_ID &&
-		   riscv_cached_marchid(0) == 0 &&
-		   riscv_cached_mimpid(0) == 0) {
+		   riscv_cached_mvendorid(0) == THEAD_VENDOR_ID) {
 		riscv_pmu_irq_num = THEAD_C9XX_RV_IRQ_PMU;
 		riscv_pmu_use_irq = true;
 	}
-- 
2.34.1




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