[PATCH 3/8] drivers/perf: riscv: Add raw event v2 support

Atish Patra atishp at rivosinc.com
Tue Nov 19 12:29:51 PST 2024


SBI v3.0 introduced a new raw event type that allows wider
mhpmeventX width to be programmed via CFG_MATCH.

Use the raw event v2 if SBI v3.0 is available.

Signed-off-by: Atish Patra <atishp at rivosinc.com>
---
 arch/riscv/include/asm/sbi.h |  4 ++++
 drivers/perf/riscv_pmu_sbi.c | 18 ++++++++++++------
 2 files changed, 16 insertions(+), 6 deletions(-)

diff --git a/arch/riscv/include/asm/sbi.h b/arch/riscv/include/asm/sbi.h
index 9be38b05f4ad..3ee9bfa5e77c 100644
--- a/arch/riscv/include/asm/sbi.h
+++ b/arch/riscv/include/asm/sbi.h
@@ -159,7 +159,10 @@ struct riscv_pmu_snapshot_data {
 
 #define RISCV_PMU_RAW_EVENT_MASK GENMASK_ULL(47, 0)
 #define RISCV_PMU_PLAT_FW_EVENT_MASK GENMASK_ULL(61, 0)
+/* SBI v3.0 allows extended hpmeventX width value */
+#define RISCV_PMU_RAW_EVENT_V2_MASK GENMASK_ULL(55, 0)
 #define RISCV_PMU_RAW_EVENT_IDX 0x20000
+#define RISCV_PMU_RAW_EVENT_V2_IDX 0x30000
 #define RISCV_PLAT_FW_EVENT	0xFFFF
 
 /** General pmu event codes specified in SBI PMU extension */
@@ -217,6 +220,7 @@ enum sbi_pmu_event_type {
 	SBI_PMU_EVENT_TYPE_HW = 0x0,
 	SBI_PMU_EVENT_TYPE_CACHE = 0x1,
 	SBI_PMU_EVENT_TYPE_RAW = 0x2,
+	SBI_PMU_EVENT_TYPE_RAW_V2 = 0x3,
 	SBI_PMU_EVENT_TYPE_FW = 0xf,
 };
 
diff --git a/drivers/perf/riscv_pmu_sbi.c b/drivers/perf/riscv_pmu_sbi.c
index 50cbdbf66bb7..f0e845ff6b79 100644
--- a/drivers/perf/riscv_pmu_sbi.c
+++ b/drivers/perf/riscv_pmu_sbi.c
@@ -59,7 +59,7 @@ asm volatile(ALTERNATIVE(						\
 #define PERF_EVENT_FLAG_USER_ACCESS	BIT(SYSCTL_USER_ACCESS)
 #define PERF_EVENT_FLAG_LEGACY		BIT(SYSCTL_LEGACY)
 
-PMU_FORMAT_ATTR(event, "config:0-47");
+PMU_FORMAT_ATTR(event, "config:0-55");
 PMU_FORMAT_ATTR(firmware, "config:62-63");
 
 static bool sbi_v2_available;
@@ -527,18 +527,24 @@ static int pmu_sbi_event_map(struct perf_event *event, u64 *econfig)
 		break;
 	case PERF_TYPE_RAW:
 		/*
-		 * As per SBI specification, the upper 16 bits must be unused
-		 * for a hardware raw event.
+		 * As per SBI v0.3 specification,
+		 *  -- the upper 16 bits must be unused for a hardware raw event.
+		 * As per SBI v3.0 specification,
+		 *  -- the upper 8 bits must be unused for a hardware raw event.
 		 * Bits 63:62 are used to distinguish between raw events
 		 * 00 - Hardware raw event
 		 * 10 - SBI firmware events
 		 * 11 - Risc-V platform specific firmware event
 		 */
-
 		switch (config >> 62) {
 		case 0:
-			ret = RISCV_PMU_RAW_EVENT_IDX;
-			*econfig = config & RISCV_PMU_RAW_EVENT_MASK;
+			if (sbi_v3_available) {
+				*econfig = config & RISCV_PMU_RAW_EVENT_V2_MASK;
+				ret = RISCV_PMU_RAW_EVENT_V2_IDX;
+			} else {
+				*econfig = config & RISCV_PMU_RAW_EVENT_MASK;
+				ret = RISCV_PMU_RAW_EVENT_IDX;
+			}
 			break;
 		case 2:
 			ret = (config & 0xFFFF) | (SBI_PMU_EVENT_TYPE_FW << 16);

-- 
2.34.1




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