[v2,2/9] drivers/perf: riscv: Add raw event v2 support

Commit Message

Atish Patra Jan. 15, 2025, 6:30 p.m. UTC

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 <[e-mail]>
---
 arch/riscv/include/asm/sbi.h |  4 ++++
 drivers/perf/riscv_pmu_sbi.c | 16 ++++++++++++----
 2 files changed, 16 insertions(+), 4 deletions(-)

Patch

diff --git a/arch/riscv/include/asm/sbi.h b/arch/riscv/include/asm/sbi.h
index 3d250824178b..6ce385a3a7bb 100644
--- a/arch/riscv/include/asm/sbi.h
+++ b/arch/riscv/include/asm/sbi.h
@@ -160,7 +160,10 @@  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 */
@@ -218,6 +221,7 @@  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 170aa93106b9..5d5b399b3e77 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;
@@ -527,8 +527,10 @@  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
@@ -537,8 +539,14 @@  static int pmu_sbi_event_map(struct perf_event *event, u64 *econfig)
 
 		switch (config >> 62) {
 		case 0:
+			if (sbi_v3_available) {
+			/* Return error any bits [56-63] is set  as it is not allowed by the spec */
+				if (!(config & ~RISCV_PMU_RAW_EVENT_V2_MASK)) {
+					*econfig = config & RISCV_PMU_RAW_EVENT_V2_MASK;
+					ret = RISCV_PMU_RAW_EVENT_V2_IDX;
+				}
 			/* Return error any bits [48-63] is set  as it is not allowed by the spec */
-			if (!(config & ~RISCV_PMU_RAW_EVENT_MASK)) {
+			} else if (!(config & ~RISCV_PMU_RAW_EVENT_MASK)) {
 				*econfig = config & RISCV_PMU_RAW_EVENT_MASK;
 				ret = RISCV_PMU_RAW_EVENT_IDX;
 			}