[Intel-gfx] [PATCH 1/4] drm/i915/selftests: Prepare the selftests for engine resets with ring submission

[Intel-gfx] [PATCH 1/4] drm/i915/selftests: Prepare the selftests for engine resets with ring submission

[Chris Wilson]

The engine resets selftests kick the tasklets, safe up until now as only
execlists supported engine resets.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
---
 drivers/gpu/drm/i915/gt/selftest_hangcheck.c | 18 ++++++++++++++----
 drivers/gpu/drm/i915/gt/selftest_reset.c     | 11 ++++++++---
 2 files changed, 22 insertions(+), 7 deletions(-)

diff --git a/drivers/gpu/drm/i915/gt/selftest_hangcheck.c b/drivers/gpu/drm/i915/gt/selftest_hangcheck.c
index 460c3e9542f4..463bb6a700c8 100644
--- a/drivers/gpu/drm/i915/gt/selftest_hangcheck.c
+++ b/drivers/gpu/drm/i915/gt/selftest_hangcheck.c
@@ -704,6 +704,7 @@ static int __igt_reset_engine(struct intel_gt *gt, bool active)
 
 	for_each_engine(engine, gt, id) {
 		unsigned int reset_count, reset_engine_count;
+		unsigned long count;
 		IGT_TIMEOUT(end_time);
 
 		if (active && !intel_engine_can_store_dword(engine))
@@ -721,6 +722,7 @@ static int __igt_reset_engine(struct intel_gt *gt, bool active)
 
 		st_engine_heartbeat_disable(engine);
 		set_bit(I915_RESET_ENGINE + id, &gt->reset.flags);
+		count = 0;
 		do {
 			if (active) {
 				struct i915_request *rq;
@@ -770,9 +772,13 @@ static int __igt_reset_engine(struct intel_gt *gt, bool active)
 				err = -EINVAL;
 				break;
 			}
+
+			count++;
 		} while (time_before(jiffies, end_time));
 		clear_bit(I915_RESET_ENGINE + id, &gt->reset.flags);
 		st_engine_heartbeat_enable(engine);
+		pr_info("%s: Completed %lu %s resets\n",
+			engine->name, count, active ? "active" : "idle");
 
 		if (err)
 			break;
@@ -1623,7 +1629,8 @@ static int igt_reset_queue(void *arg)
 			prev = rq;
 			count++;
 		} while (time_before(jiffies, end_time));
-		pr_info("%s: Completed %d resets\n", engine->name, count);
+		pr_info("%s: Completed %d queued resets\n",
+			engine->name, count);
 
 		*h.batch = MI_BATCH_BUFFER_END;
 		intel_gt_chipset_flush(engine->gt);
@@ -1720,7 +1727,8 @@ static int __igt_atomic_reset_engine(struct intel_engine_cs *engine,
 	GEM_TRACE("i915_reset_engine(%s:%s) under %s\n",
 		  engine->name, mode, p->name);
 
-	tasklet_disable(t);
+	if (t->func)
+		tasklet_disable(t);
 	if (strcmp(p->name, "softirq"))
 		local_bh_disable();
 	p->critical_section_begin();
@@ -1730,8 +1738,10 @@ static int __igt_atomic_reset_engine(struct intel_engine_cs *engine,
 	p->critical_section_end();
 	if (strcmp(p->name, "softirq"))
 		local_bh_enable();
-	tasklet_enable(t);
-	tasklet_hi_schedule(t);
+	if (t->func) {
+		tasklet_enable(t);
+		tasklet_hi_schedule(t);
+	}
 
 	if (err)
 		pr_err("i915_reset_engine(%s:%s) failed under %s\n",
diff --git a/drivers/gpu/drm/i915/gt/selftest_reset.c b/drivers/gpu/drm/i915/gt/selftest_reset.c
index b7befcfbdcde..8784257ec808 100644
--- a/drivers/gpu/drm/i915/gt/selftest_reset.c
+++ b/drivers/gpu/drm/i915/gt/selftest_reset.c
@@ -321,7 +321,10 @@ static int igt_atomic_engine_reset(void *arg)
 		goto out_unlock;
 
 	for_each_engine(engine, gt, id) {
-		tasklet_disable(&engine->execlists.tasklet);
+		struct tasklet_struct *t = &engine->execlists.tasklet;
+
+		if (t->func)
+			tasklet_disable(t);
 		intel_engine_pm_get(engine);
 
 		for (p = igt_atomic_phases; p->name; p++) {
@@ -345,8 +348,10 @@ static int igt_atomic_engine_reset(void *arg)
 		}
 
 		intel_engine_pm_put(engine);
-		tasklet_enable(&engine->execlists.tasklet);
-		tasklet_hi_schedule(&engine->execlists.tasklet);
+		if (t->func) {
+			tasklet_enable(t);
+			tasklet_hi_schedule(t);
+		}
 		if (err)
 			break;
 	}
-- 
2.20.1

_______________________________________________
Intel-gfx mailing list
Intel-gfx@lists.freedesktop.org
https://lists.freedesktop.org/mailman/listinfo/intel-gfx

[Intel-gfx] [PATCH 2/4] drm/i915/gt: Lift stop_ring() to reset_prepare

[Chris Wilson]

Push the sleeping stop_ring() out of the reset resume function to reset
prepare; we are not allowed to sleep in the former.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
---
 .../gpu/drm/i915/gt/intel_ring_submission.c   | 97 +++++++------------
 1 file changed, 36 insertions(+), 61 deletions(-)

diff --git a/drivers/gpu/drm/i915/gt/intel_ring_submission.c b/drivers/gpu/drm/i915/gt/intel_ring_submission.c
index 8d0964d2d597..44159595d909 100644
--- a/drivers/gpu/drm/i915/gt/intel_ring_submission.c
+++ b/drivers/gpu/drm/i915/gt/intel_ring_submission.c
@@ -157,21 +157,6 @@ static void ring_setup_status_page(struct intel_engine_cs *engine)
 	flush_cs_tlb(engine);
 }
 
-static bool stop_ring(struct intel_engine_cs *engine)
-{
-	intel_engine_stop_cs(engine);
-
-	ENGINE_WRITE(engine, RING_HEAD, ENGINE_READ(engine, RING_TAIL));
-
-	ENGINE_WRITE(engine, RING_HEAD, 0);
-	ENGINE_WRITE(engine, RING_TAIL, 0);
-
-	/* The ring must be empty before it is disabled */
-	ENGINE_WRITE(engine, RING_CTL, 0);
-
-	return (ENGINE_READ(engine, RING_HEAD) & HEAD_ADDR) == 0;
-}
-
 static struct i915_address_space *vm_alias(struct i915_address_space *vm)
 {
 	if (i915_is_ggtt(vm))
@@ -213,31 +198,6 @@ static int xcs_resume(struct intel_engine_cs *engine)
 
 	intel_uncore_forcewake_get(engine->uncore, FORCEWAKE_ALL);
 
-	/* WaClearRingBufHeadRegAtInit:ctg,elk */
-	if (!stop_ring(engine)) {
-		/* G45 ring initialization often fails to reset head to zero */
-		drm_dbg(&dev_priv->drm, "%s head not reset to zero "
-			"ctl %08x head %08x tail %08x start %08x\n",
-			engine->name,
-			ENGINE_READ(engine, RING_CTL),
-			ENGINE_READ(engine, RING_HEAD),
-			ENGINE_READ(engine, RING_TAIL),
-			ENGINE_READ(engine, RING_START));
-
-		if (!stop_ring(engine)) {
-			drm_err(&dev_priv->drm,
-				"failed to set %s head to zero "
-				"ctl %08x head %08x tail %08x start %08x\n",
-				engine->name,
-				ENGINE_READ(engine, RING_CTL),
-				ENGINE_READ(engine, RING_HEAD),
-				ENGINE_READ(engine, RING_TAIL),
-				ENGINE_READ(engine, RING_START));
-			ret = -EIO;
-			goto out;
-		}
-	}
-
 	if (HWS_NEEDS_PHYSICAL(dev_priv))
 		ring_setup_phys_status_page(engine);
 	else
@@ -339,11 +299,21 @@ static void xcs_sanitize(struct intel_engine_cs *engine)
 	clflush_cache_range(engine->status_page.addr, PAGE_SIZE);
 }
 
+static bool stop_ring(struct intel_engine_cs *engine)
+{
+	ENGINE_WRITE_FW(engine, RING_HEAD, ENGINE_READ_FW(engine, RING_TAIL));
+
+	ENGINE_WRITE_FW(engine, RING_HEAD, 0);
+	ENGINE_WRITE_FW(engine, RING_TAIL, 0);
+
+	/* The ring must be empty before it is disabled */
+	ENGINE_WRITE_FW(engine, RING_CTL, 0);
+
+	return (ENGINE_READ_FW(engine, RING_HEAD) & HEAD_ADDR) == 0;
+}
+
 static void reset_prepare(struct intel_engine_cs *engine)
 {
-	struct intel_uncore *uncore = engine->uncore;
-	const u32 base = engine->mmio_base;
-
 	/*
 	 * We stop engines, otherwise we might get failed reset and a
 	 * dead gpu (on elk). Also as modern gpu as kbl can suffer
@@ -355,30 +325,35 @@ static void reset_prepare(struct intel_engine_cs *engine)
 	 * WaKBLVECSSemaphoreWaitPoll:kbl (on ALL_ENGINES)
 	 *
 	 * WaMediaResetMainRingCleanup:ctg,elk (presumably)
+	 * WaClearRingBufHeadRegAtInit:ctg,elk
 	 *
 	 * FIXME: Wa for more modern gens needs to be validated
 	 */
 	ENGINE_TRACE(engine, "\n");
+	intel_engine_stop_cs(engine);
 
-	if (intel_engine_stop_cs(engine))
-		ENGINE_TRACE(engine, "timed out on STOP_RING\n");
+	if (!stop_ring(engine)) {
+		/* G45 ring initialization often fails to reset head to zero */
+		drm_dbg(&engine->i915->drm,
+			"%s head not reset to zero "
+			"ctl %08x head %08x tail %08x start %08x\n",
+			engine->name,
+			ENGINE_READ_FW(engine, RING_CTL),
+			ENGINE_READ_FW(engine, RING_HEAD),
+			ENGINE_READ_FW(engine, RING_TAIL),
+			ENGINE_READ_FW(engine, RING_START));
+	}
 
-	intel_uncore_write_fw(uncore,
-			      RING_HEAD(base),
-			      intel_uncore_read_fw(uncore, RING_TAIL(base)));
-	intel_uncore_posting_read_fw(uncore, RING_HEAD(base)); /* paranoia */
-
-	intel_uncore_write_fw(uncore, RING_HEAD(base), 0);
-	intel_uncore_write_fw(uncore, RING_TAIL(base), 0);
-	intel_uncore_posting_read_fw(uncore, RING_TAIL(base));
-
-	/* The ring must be empty before it is disabled */
-	intel_uncore_write_fw(uncore, RING_CTL(base), 0);
-
-	/* Check acts as a post */
-	if (intel_uncore_read_fw(uncore, RING_HEAD(base)))
-		ENGINE_TRACE(engine, "ring head [%x] not parked\n",
-			     intel_uncore_read_fw(uncore, RING_HEAD(base)));
+	if (!stop_ring(engine)) {
+		drm_err(&engine->i915->drm,
+			"failed to set %s head to zero "
+			"ctl %08x head %08x tail %08x start %08x\n",
+			engine->name,
+			ENGINE_READ_FW(engine, RING_CTL),
+			ENGINE_READ_FW(engine, RING_HEAD),
+			ENGINE_READ_FW(engine, RING_TAIL),
+			ENGINE_READ_FW(engine, RING_START));
+	}
 }
 
 static void reset_rewind(struct intel_engine_cs *engine, bool stalled)
-- 
2.20.1

_______________________________________________
Intel-gfx mailing list
Intel-gfx@lists.freedesktop.org
https://lists.freedesktop.org/mailman/listinfo/intel-gfx

[Intel-gfx] [PATCH 3/4] drm/i915/gt: Pull ring submission resume under its caller forcewake

[Chris Wilson]

Take advantage of calling xcs_resume under a forcewake by using direct
mmio access. In particular, we can avoid the sleeping variants to allow
resume to be called from softirq context, required for engine resets.

v2: Keep the positing read at the start of resume as a guardian memory
barrier.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
---
 .../gpu/drm/i915/gt/intel_ring_submission.c   | 93 +++++++++----------
 1 file changed, 42 insertions(+), 51 deletions(-)

diff --git a/drivers/gpu/drm/i915/gt/intel_ring_submission.c b/drivers/gpu/drm/i915/gt/intel_ring_submission.c
index 44159595d909..bf2834424add 100644
--- a/drivers/gpu/drm/i915/gt/intel_ring_submission.c
+++ b/drivers/gpu/drm/i915/gt/intel_ring_submission.c
@@ -122,31 +122,27 @@ static void set_hwsp(struct intel_engine_cs *engine, u32 offset)
 		hwsp = RING_HWS_PGA(engine->mmio_base);
 	}
 
-	intel_uncore_write(engine->uncore, hwsp, offset);
-	intel_uncore_posting_read(engine->uncore, hwsp);
+	intel_uncore_write_fw(engine->uncore, hwsp, offset);
+	intel_uncore_posting_read_fw(engine->uncore, hwsp);
 }
 
 static void flush_cs_tlb(struct intel_engine_cs *engine)
 {
-	struct drm_i915_private *dev_priv = engine->i915;
-
-	if (!IS_GEN_RANGE(dev_priv, 6, 7))
+	if (!IS_GEN_RANGE(engine->i915, 6, 7))
 		return;
 
 	/* ring should be idle before issuing a sync flush*/
-	drm_WARN_ON(&dev_priv->drm,
-		    (ENGINE_READ(engine, RING_MI_MODE) & MODE_IDLE) == 0);
+	GEM_DEBUG_WARN_ON((ENGINE_READ(engine, RING_MI_MODE) & MODE_IDLE) == 0);
 
-	ENGINE_WRITE(engine, RING_INSTPM,
-		     _MASKED_BIT_ENABLE(INSTPM_TLB_INVALIDATE |
-					INSTPM_SYNC_FLUSH));
-	if (intel_wait_for_register(engine->uncore,
-				    RING_INSTPM(engine->mmio_base),
-				    INSTPM_SYNC_FLUSH, 0,
-				    1000))
-		drm_err(&dev_priv->drm,
-			"%s: wait for SyncFlush to complete for TLB invalidation timed out\n",
-			engine->name);
+	ENGINE_WRITE_FW(engine, RING_INSTPM,
+			_MASKED_BIT_ENABLE(INSTPM_TLB_INVALIDATE |
+					   INSTPM_SYNC_FLUSH));
+	if (__intel_wait_for_register_fw(engine->uncore,
+					 RING_INSTPM(engine->mmio_base),
+					 INSTPM_SYNC_FLUSH, 0,
+					 2000, 0, NULL))
+		ENGINE_TRACE(engine,
+			     "wait for SyncFlush to complete for TLB invalidation timed out\n");
 }
 
 static void ring_setup_status_page(struct intel_engine_cs *engine)
@@ -177,13 +173,13 @@ static void set_pp_dir(struct intel_engine_cs *engine)
 	if (!vm)
 		return;
 
-	ENGINE_WRITE(engine, RING_PP_DIR_DCLV, PP_DIR_DCLV_2G);
-	ENGINE_WRITE(engine, RING_PP_DIR_BASE, pp_dir(vm));
+	ENGINE_WRITE_FW(engine, RING_PP_DIR_DCLV, PP_DIR_DCLV_2G);
+	ENGINE_WRITE_FW(engine, RING_PP_DIR_BASE, pp_dir(vm));
 
 	if (INTEL_GEN(engine->i915) >= 7) {
-		ENGINE_WRITE(engine,
-			     RING_MODE_GEN7,
-			     _MASKED_BIT_ENABLE(GFX_PPGTT_ENABLE));
+		ENGINE_WRITE_FW(engine,
+				RING_MODE_GEN7,
+				_MASKED_BIT_ENABLE(GFX_PPGTT_ENABLE));
 	}
 }
 
@@ -191,13 +187,10 @@ static int xcs_resume(struct intel_engine_cs *engine)
 {
 	struct drm_i915_private *dev_priv = engine->i915;
 	struct intel_ring *ring = engine->legacy.ring;
-	int ret = 0;
 
 	ENGINE_TRACE(engine, "ring:{HEAD:%04x, TAIL:%04x}\n",
 		     ring->head, ring->tail);
 
-	intel_uncore_forcewake_get(engine->uncore, FORCEWAKE_ALL);
-
 	if (HWS_NEEDS_PHYSICAL(dev_priv))
 		ring_setup_phys_status_page(engine);
 	else
@@ -214,7 +207,7 @@ static int xcs_resume(struct intel_engine_cs *engine)
 	 * also enforces ordering), otherwise the hw might lose the new ring
 	 * register values.
 	 */
-	ENGINE_WRITE(engine, RING_START, i915_ggtt_offset(ring->vma));
+	ENGINE_WRITE_FW(engine, RING_START, i915_ggtt_offset(ring->vma));
 
 	/* Check that the ring offsets point within the ring! */
 	GEM_BUG_ON(!intel_ring_offset_valid(ring, ring->head));
@@ -224,46 +217,44 @@ static int xcs_resume(struct intel_engine_cs *engine)
 	set_pp_dir(engine);
 
 	/* First wake the ring up to an empty/idle ring */
-	ENGINE_WRITE(engine, RING_HEAD, ring->head);
-	ENGINE_WRITE(engine, RING_TAIL, ring->head);
+	ENGINE_WRITE_FW(engine, RING_HEAD, ring->head);
+	ENGINE_WRITE_FW(engine, RING_TAIL, ring->head);
 	ENGINE_POSTING_READ(engine, RING_TAIL);
 
-	ENGINE_WRITE(engine, RING_CTL, RING_CTL_SIZE(ring->size) | RING_VALID);
+	ENGINE_WRITE_FW(engine, RING_CTL,
+			RING_CTL_SIZE(ring->size) | RING_VALID);
 
 	/* If the head is still not zero, the ring is dead */
-	if (intel_wait_for_register(engine->uncore,
-				    RING_CTL(engine->mmio_base),
-				    RING_VALID, RING_VALID,
-				    50)) {
-		drm_err(&dev_priv->drm, "%s initialization failed "
-			  "ctl %08x (valid? %d) head %08x [%08x] tail %08x [%08x] start %08x [expected %08x]\n",
-			  engine->name,
-			  ENGINE_READ(engine, RING_CTL),
-			  ENGINE_READ(engine, RING_CTL) & RING_VALID,
-			  ENGINE_READ(engine, RING_HEAD), ring->head,
-			  ENGINE_READ(engine, RING_TAIL), ring->tail,
-			  ENGINE_READ(engine, RING_START),
-			  i915_ggtt_offset(ring->vma));
-		ret = -EIO;
-		goto out;
+	if (__intel_wait_for_register_fw(engine->uncore,
+					 RING_CTL(engine->mmio_base),
+					 RING_VALID, RING_VALID,
+					 5000, 0, NULL)) {
+		drm_err(&dev_priv->drm,
+			"%s initialization failed; "
+			"ctl %08x (valid? %d) head %08x [%08x] tail %08x [%08x] start %08x [expected %08x]\n",
+			engine->name,
+			ENGINE_READ(engine, RING_CTL),
+			ENGINE_READ(engine, RING_CTL) & RING_VALID,
+			ENGINE_READ(engine, RING_HEAD), ring->head,
+			ENGINE_READ(engine, RING_TAIL), ring->tail,
+			ENGINE_READ(engine, RING_START),
+			i915_ggtt_offset(ring->vma));
+		return -EIO;
 	}
 
 	if (INTEL_GEN(dev_priv) > 2)
-		ENGINE_WRITE(engine,
-			     RING_MI_MODE, _MASKED_BIT_DISABLE(STOP_RING));
+		ENGINE_WRITE_FW(engine,
+				RING_MI_MODE, _MASKED_BIT_DISABLE(STOP_RING));
 
 	/* Now awake, let it get started */
 	if (ring->tail != ring->head) {
-		ENGINE_WRITE(engine, RING_TAIL, ring->tail);
+		ENGINE_WRITE_FW(engine, RING_TAIL, ring->tail);
 		ENGINE_POSTING_READ(engine, RING_TAIL);
 	}
 
 	/* Papering over lost _interrupts_ immediately following the restart */
 	intel_engine_signal_breadcrumbs(engine);
-out:
-	intel_uncore_forcewake_put(engine->uncore, FORCEWAKE_ALL);
-
-	return ret;
+	return 0;
 }
 
 static void sanitize_hwsp(struct intel_engine_cs *engine)
-- 
2.20.1

_______________________________________________
Intel-gfx mailing list
Intel-gfx@lists.freedesktop.org
https://lists.freedesktop.org/mailman/listinfo/intel-gfx

[Intel-gfx] [PATCH 4/4] drm/i915: Mark per-engine-reset as supported on gen7

[Chris Wilson]

The benefit of only resetting a single engine is that we leave other
streams of userspace work intact across a hang; vital for process
isolation. We had wired up individual engine resets for gen6, but only
enabled it from gen8; now let's turn it on for the forgotten gen7. gen6
is still a mystery as how to unravel some global state that appears to
be reset along with an engine (in particular the ppgtt enabling in
GFX_MODE).

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
---
 drivers/gpu/drm/i915/i915_pci.c | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/drivers/gpu/drm/i915/i915_pci.c b/drivers/gpu/drm/i915/i915_pci.c
index 39608381b4a4..020b5f561f07 100644
--- a/drivers/gpu/drm/i915/i915_pci.c
+++ b/drivers/gpu/drm/i915/i915_pci.c
@@ -455,6 +455,7 @@ static const struct intel_device_info snb_m_gt2_info = {
 	.has_llc = 1, \
 	.has_rc6 = 1, \
 	.has_rc6p = 1, \
+	.has_reset_engine = true, \
 	.has_rps = true, \
 	.dma_mask_size = 40, \
 	.ppgtt_type = INTEL_PPGTT_ALIASING, \
@@ -513,6 +514,7 @@ static const struct intel_device_info vlv_info = {
 	.cpu_transcoder_mask = BIT(TRANSCODER_A) | BIT(TRANSCODER_B),
 	.has_runtime_pm = 1,
 	.has_rc6 = 1,
+	.has_reset_engine = true,
 	.has_rps = true,
 	.display.has_gmch = 1,
 	.display.has_hotplug = 1,
@@ -571,8 +573,7 @@ static const struct intel_device_info hsw_gt3_info = {
 	.dma_mask_size = 39, \
 	.ppgtt_type = INTEL_PPGTT_FULL, \
 	.ppgtt_size = 48, \
-	.has_64bit_reloc = 1, \
-	.has_reset_engine = 1
+	.has_64bit_reloc = 1
 
 #define BDW_PLATFORM \
 	GEN8_FEATURES, \
-- 
2.20.1

_______________________________________________
Intel-gfx mailing list
Intel-gfx@lists.freedesktop.org
https://lists.freedesktop.org/mailman/listinfo/intel-gfx