[PATCH] drm/i915/selftests: Forcewake stress

[Tvrtko Ursulin]

From: Tvrtko Ursulin <tvrtko.ursulin at intel.com>

...

Signed-off-by: Tvrtko Ursulin <tvrtko.ursulin at intel.com>
---
 drivers/gpu/drm/i915/selftests/intel_uncore.c | 56 +++++++++++++++++++
 1 file changed, 56 insertions(+)

diff --git a/drivers/gpu/drm/i915/selftests/intel_uncore.c b/drivers/gpu/drm/i915/selftests/intel_uncore.c
index bc8128170a99..3e3d74e4370f 100644
--- a/drivers/gpu/drm/i915/selftests/intel_uncore.c
+++ b/drivers/gpu/drm/i915/selftests/intel_uncore.c
@@ -336,12 +336,68 @@ static int live_fw_table(void *arg)
 				    GRAPHICS_VER(gt->i915) >= 9);
 }
 
+static int live_forcewake_stress(void *arg)
+{
+	struct intel_gt *gt = arg;
+	struct intel_uncore *uncore = gt->uncore;
+	unsigned int period_us = 16667;
+	intel_wakeref_t wakeref;
+
+	if (!uncore->fw_domains)
+		return 0;
+
+	wakeref = intel_runtime_pm_get(uncore->rpm);
+
+	while (period_us) {
+		struct intel_uncore_forcewake_domain *d;
+		unsigned long cnt;
+		unsigned int tmp;
+		ktime_t start;
+
+		for_each_fw_domain(d, uncore, tmp) {
+			start = ktime_get();
+			cnt = 0;
+
+			do {
+				intel_uncore_forcewake_get(uncore, d->mask);
+				udelay(period_us / 2);
+				intel_uncore_forcewake_put(uncore, d->mask);
+				udelay(period_us / 2);
+				cnt++;
+			} while (ktime_to_ms(ktime_sub(ktime_get(), start)) < 200);
+
+			pr_info("fw-domain-%x: %lu cycles with %uus period\n",
+				d->mask, cnt, period_us);
+		}
+
+		start = ktime_get();
+		cnt = 0;
+		do {
+			intel_uncore_forcewake_get(uncore, FORCEWAKE_ALL);
+			udelay(period_us / 2);
+			intel_uncore_forcewake_put(uncore, FORCEWAKE_ALL);
+			udelay(period_us / 2);
+			cnt++;
+		} while (ktime_to_ms(ktime_sub(ktime_get(), start)) < 200);
+
+		pr_info("all-fw-domains: %lu cycles with %uus period\n",
+			cnt, period_us);
+
+		period_us /= 2;
+	}
+
+	intel_runtime_pm_put(uncore->rpm, wakeref);
+
+	return 0;
+}
+
 int intel_uncore_live_selftests(struct drm_i915_private *i915)
 {
 	static const struct i915_subtest tests[] = {
 		SUBTEST(live_fw_table),
 		SUBTEST(live_forcewake_ops),
 		SUBTEST(live_forcewake_domains),
+		SUBTEST(live_forcewake_stress),
 	};
 
 	return intel_gt_live_subtests(tests, &i915->gt);
-- 
2.32.0