[RFC 5/9] RISC-V: Add SBI PMU snapshot definitions

Atish Patra atishp at rivosinc.com
Mon Dec 4 18:43:06 PST 2023


SBI PMU Snapshot function optimizes the number of traps to
higher privilege mode by leveraging a shared memory between the S/VS-mode
and the M/HS mode. Add the definitions for that extension

Signed-off-by: Atish Patra <atishp at rivosinc.com>
---
 arch/riscv/include/asm/sbi.h | 10 ++++++++++
 1 file changed, 10 insertions(+)

diff --git a/arch/riscv/include/asm/sbi.h b/arch/riscv/include/asm/sbi.h
index f3eeca79a02d..29821addb9b7 100644
--- a/arch/riscv/include/asm/sbi.h
+++ b/arch/riscv/include/asm/sbi.h
@@ -122,6 +122,7 @@ enum sbi_ext_pmu_fid {
 	SBI_EXT_PMU_COUNTER_STOP,
 	SBI_EXT_PMU_COUNTER_FW_READ,
 	SBI_EXT_PMU_COUNTER_FW_READ_HI,
+	SBI_EXT_PMU_SNAPSHOT_SET_SHMEM,
 };
 
 union sbi_pmu_ctr_info {
@@ -138,6 +139,13 @@ union sbi_pmu_ctr_info {
 	};
 };
 
+/* Data structure to contain the pmu snapshot data */
+struct riscv_pmu_snapshot_data {
+	uint64_t ctr_overflow_mask;
+	uint64_t ctr_values[64];
+	uint64_t reserved[447];
+};
+
 #define RISCV_PMU_RAW_EVENT_MASK GENMASK_ULL(47, 0)
 #define RISCV_PMU_RAW_EVENT_IDX 0x20000
 
@@ -234,9 +242,11 @@ enum sbi_pmu_ctr_type {
 
 /* Flags defined for counter start function */
 #define SBI_PMU_START_FLAG_SET_INIT_VALUE (1 << 0)
+#define SBI_PMU_START_FLAG_INIT_FROM_SNAPSHOT (1 << 1)
 
 /* Flags defined for counter stop function */
 #define SBI_PMU_STOP_FLAG_RESET (1 << 0)
+#define SBI_PMU_STOP_FLAG_TAKE_SNAPSHOT (1 << 1)
 
 enum sbi_ext_dbcn_fid {
 	SBI_EXT_DBCN_CONSOLE_WRITE = 0,
-- 
2.34.1




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