drm/i915/pmu: Support PMU for all engines

Given how the metrics are already exported, we also need to run sampling
over engines from all GTs.

Problem of GT frequencies is left for later.
Signed-off-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Reviewed-by: Umesh Nerlige Ramappa <umesh.nerlige.ramappa@intel.com>
Signed-off-by: Umesh Nerlige Ramappa <umesh.nerlige.ramappa@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20230519154946.3751971-3-umesh.nerlige.ramappa@intel.com

drivers/gpu/drm/i915/i915_pmu.c

@@ -10,6 +10,7 @@
 #include "gt/intel_engine_pm.h"
 #include "gt/intel_engine_regs.h"
 #include "gt/intel_engine_user.h"
+#include "gt/intel_gt.h"
 #include "gt/intel_gt_pm.h"
 #include "gt/intel_gt_regs.h"
 #include "gt/intel_rc6.h"
@@ -425,8 +426,9 @@ static enum hrtimer_restart i915_sample(struct hrtimer *hrtimer)
 	struct drm_i915_private *i915 =
 		container_of(hrtimer, struct drm_i915_private, pmu.timer);
 	struct i915_pmu *pmu = &i915->pmu;
-	struct intel_gt *gt = to_gt(i915);
 	unsigned int period_ns;
+	struct intel_gt *gt;
+	unsigned int i;
 	ktime_t now;
 
 	if (!READ_ONCE(pmu->timer_enabled))
@@ -442,8 +444,13 @@ static enum hrtimer_restart i915_sample(struct hrtimer *hrtimer)
 	 * grabbing the forcewake. However the potential error from timer call-
 	 * back delay greatly dominates this so we keep it simple.
 	 */
-	engines_sample(gt, period_ns);
-	frequency_sample(gt, period_ns);
+
+	for_each_gt(gt, i915, i) {
+		engines_sample(gt, period_ns);
+
+		if (i == 0) /* FIXME */
+			frequency_sample(gt, period_ns);
+	}
 
 	hrtimer_forward(hrtimer, now, ns_to_ktime(PERIOD));