[PATCH v14 7/7] drm/xe/pmu: Add GT C6 events

Lucas De Marchi
2025-01-22T06:24:18Z

From: Vinay Belgaumkar <vinay.belgaumkar@intel.com>

Provide a PMU interface for GT C6 residency counters. The implementation
is ported over from the i915 PMU code. Residency is provided in units of
ms(like sysfs entry in - /sys/class/drm/card0/device/tile0/gt0/gtidle).

Sample usage and output:

$ perf list | grep gt-c6
xe_0000_00_02.0/gt-c6-residency/ [Kernel PMU event]

$ tail /sys/bus/event_source/devices/xe_0000_00_02.0/events/gt-c6-residency*
==> /sys/bus/event_source/devices/xe_0000_00_02.0/events/gt-c6-residency <==
event=0x01

==> /sys/bus/event_source/devices/xe_0000_00_02.0/events/gt-c6-residency.unit <==
ms

$ perf stat -e xe_0000_00_02.0/gt-c6-residency,gt=0/ -I1000
# time counts unit events
1.001196056 1,001 ms xe_0000_00_02.0/gt-c6-residency,gt=0/
2.005216219 1,003 ms xe_0000_00_02.0/gt-c6-residency,gt=0/

Signed-off-by: Vinay Belgaumkar <vinay.belgaumkar@intel.com>
Signed-off-by: Lucas De Marchi <lucas.demarchi@intel.com>
---
drivers/gpu/drm/xe/xe_pmu.c | 13 +++++++++++--
1 file changed, 11 insertions(+), 2 deletions(-)

diff --git a/drivers/gpu/drm/xe/xe_pmu.c b/drivers/gpu/drm/xe/xe_pmu.c
index 8d938d67c1f2c..a2e4addd3dd7e 100644
--- a/drivers/gpu/drm/xe/xe_pmu.c
+++ b/drivers/gpu/drm/xe/xe_pmu.c
@@ -11,6 +11,7 @@
#include "xe_device.h"
#include "xe_force_wake.h"
#include "xe_gt_clock.h"
+#include "xe_gt_idle.h"
#include "xe_gt_printk.h"
#include "xe_mmio.h"
#include "xe_macros.h"
@@ -122,12 +123,16 @@ static int xe_pmu_event_init(struct perf_event *event)
static u64 __xe_pmu_event_read(struct perf_event *event)
{
struct xe_gt *gt = event_to_gt(event);
- u64 val = 0;

if (!gt)
return 0;

- return val;
+ switch (config_to_event_id(event->attr.config)) {
+ case XE_PMU_EVENT_GT_C6_RESIDENCY:
+ return xe_gt_idle_residency_msec(&gt->gtidle);
+ }
+
+ return 0;
}

static void xe_pmu_event_update(struct perf_event *event)
@@ -268,6 +273,10 @@ static const struct attribute_group pmu_events_attr_group = {

static void set_supported_events(struct xe_pmu *pmu)
{
+ struct xe_device *xe = container_of(pmu, typeof(*xe), pmu);
+
+ if (!xe->info.skip_guc_pc)
+ pmu->supported_events |= BIT_ULL(XE_PMU_EVENT_GT_C6_RESIDENCY);
}

/**
--
2.48.0