On Fri, May 23, 2025 at 12:33 AM Atish Patra <atishp@xxxxxxxxxxxx> wrote:
>
> 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@xxxxxxxxxxxx>
> ---
> arch/riscv/include/asm/sbi.h | 4 ++++
> drivers/perf/riscv_pmu_sbi.c | 16 ++++++++++++----
> 2 files changed, 16 insertions(+), 4 deletions(-)
>
> 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 cfd6946fca42..273ed70098a3 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 text here should be "As-per SBI v2.0 ..."
> + * -- 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;
> }
>
> --
> 2.43.0
>
Otherwise, this looks good to me.
Reviewed-by: Anup Patel <anup@xxxxxxxxxxxxxx>
Regards,
Anup
