[PATCH v8 17/22] RISC-V: perf: Add legacy event encodings via sysfs

[Charlie Jenkins]

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> Define sysfs details for the legacy events so that any tool can
> parse these to understand the minimum set of legacy events
> supported by the platform. The sysfs entry will describe both event
> encoding and corresponding counter map so that an perf event can be
> programmed accordingly.
> 
> Signed-off-by: Atish Patra <atishp at rivosinc.com>
>
> diff --git a/drivers/perf/riscv_pmu_sbi.c b/drivers/perf/riscv_pmu_sbi.c
> index 19d9e4750424..8d56bef95a1b 100644
> --- a/drivers/perf/riscv_pmu_sbi.c
> +++ b/drivers/perf/riscv_pmu_sbi.c
> @@ -131,7 +131,20 @@ static struct attribute_group riscv_cdeleg_pmu_format_group = {
>  	.attrs = riscv_cdeleg_pmu_formats_attr,
>  };
>  
> +#define RVPMU_EVENT_ATTR_RESOLVE(m) #m
> +#define RVPMU_EVENT_CMASK_ATTR(_name, _var, config, mask) \
> +	PMU_EVENT_ATTR_STRING(_name, rvpmu_event_attr_##_var, \
> +			      "event=" RVPMU_EVENT_ATTR_RESOLVE(config) \
> +			      ",counterid_mask=" RVPMU_EVENT_ATTR_RESOLVE(mask))
> +
> +#define RVPMU_EVENT_ATTR_PTR(name) (&rvpmu_event_attr_##name.attr.attr)
> +
> +static struct attribute_group riscv_cdeleg_pmu_event_group __ro_after_init = {
> +	.name = "events",
> +};
> +
>  static const struct attribute_group *riscv_cdeleg_pmu_attr_groups[] = {
> +	&riscv_cdeleg_pmu_event_group,
>  	&riscv_cdeleg_pmu_format_group,
>  	NULL,
>  };
> @@ -447,11 +460,14 @@ struct riscv_vendor_pmu_events {
>  	const struct riscv_pmu_event *hw_event_map;
>  	const struct riscv_pmu_event (*cache_event_map)[PERF_COUNT_HW_CACHE_OP_MAX]
>  						       [PERF_COUNT_HW_CACHE_RESULT_MAX];
> +	struct attribute **attrs_events;
>  };
>  
> -#define RISCV_VENDOR_PMU_EVENTS(_vendorid, _archid, _implid, _hw_event_map, _cache_event_map) \
> +#define RISCV_VENDOR_PMU_EVENTS(_vendorid, _archid, _implid, _hw_event_map, \
> +				_cache_event_map, _attrs) \
>  	{ .vendorid = _vendorid, .archid = _archid, .implid = _implid, \
> -	  .hw_event_map = _hw_event_map, .cache_event_map = _cache_event_map },
> +	  .hw_event_map = _hw_event_map, .cache_event_map = _cache_event_map, \
> +	  .attrs_events = _attrs },
>  
>  static struct riscv_vendor_pmu_events pmu_vendor_events_table[] = {
>  };
> @@ -473,6 +489,8 @@ static void __init rvpmu_vendor_register_events(void)
>  		    pmu_vendor_events_table[i].archid == arch_id) {
>  			current_pmu_hw_event_map = pmu_vendor_events_table[i].hw_event_map;
>  			current_pmu_cache_event_map = pmu_vendor_events_table[i].cache_event_map;
> +			riscv_cdeleg_pmu_event_group.attrs =
> +							pmu_vendor_events_table[i].attrs_events;
>  			break;
>  		}
>  	}

Reviewed-by: Charlie Jenkins <thecharlesjenkins at gmail.com>
Tested-by: Charlie Jenkins <thecharlesjenkins at gmail.com>

-- 
- Charlie