[PATCH v9 17/20] RISC-V: perf: Add legacy event encodings via sysfs

[Atish Patra <atish.patra@linux.dev>]

From: Atish Patra <atishp@rivosinc.com>

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@rivosinc.com>
Reviewed-by: Charlie Jenkins <thecharlesjenkins@gmail.com>
Tested-by: Charlie Jenkins <thecharlesjenkins@gmail.com>
---
 drivers/perf/riscv_pmu_sbi.c | 22 ++++++++++++++++++++--
 1 file changed, 20 insertions(+), 2 deletions(-)

diff --git a/drivers/perf/riscv_pmu_sbi.c b/drivers/perf/riscv_pmu_sbi.c
index ee0c07785927..5eb49db8bc7c 100644
--- a/drivers/perf/riscv_pmu_sbi.c
+++ b/drivers/perf/riscv_pmu_sbi.c
@@ -130,7 +130,20 @@ 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,
 };
@@ -446,11 +459,14 @@ 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[] = {
 };
@@ -472,6 +488,8 @@ 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;
 		}
 	}

-- 
2.53.0-Meta