Merge tag 'drm-next-2019-05-09' of git://anongit.freedesktop.org/drm/drm

Pull drm updates from Dave Airlie:
 "This has two exciting community drivers for ARM Mali accelerators.
  Since ARM has never been open source friendly on the GPU side of the
  house, the community has had to create open source drivers for the
  Mali GPUs. Lima covers the older t4xx and panfrost the newer 6xx/7xx
  series. Well done to all involved and hopefully this will help ARM
  head in the right direction.

  There is also now the ability if you don't have any of the legacy
  drivers enabled (pre-KMS) to remove all the pre-KMS support code from
  the core drm, this saves 10% or so in codesize on my machine.

  i915 also enable Icelake/Elkhart Lake Gen11 GPUs by default, vboxvideo
  moves out of staging.

  There are also some rcar-du patches which crossover with media tree
  but all should be acked by Mauro.

  Summary:

  uapi changes:
   - Colorspace connector property
   - fourcc - new YUV formts
   - timeline sync objects initially merged
   - expose FB_DAMAGE_CLIPS to atomic userspace

  new drivers:
   - vboxvideo: moved out of staging
   - aspeed: ASPEED SoC BMC chip display support
   - lima: ARM Mali4xx GPU acceleration driver support
   - panfrost: ARM Mali6xx/7xx Midgard/Bitfrost acceleration driver support

  core:
   - component helper docs
   - unplugging fixes
   - devm device init
   - MIPI/DSI rate control
   - shmem backed gem objects
   - connector, display_info, edid_quirks cleanups
   - dma_buf fence chain support
   - 64-bit dma-fence seqno comparison fixes
   - move initial fb config code to core
   - gem fence array helpers for Lima
   - ability to remove legacy support code if no drivers requires it (removes 10% of drm.ko size)
   - lease fixes

  ttm:
   - unified DRM_FILE_PAGE_OFFSET handling
   - Account for kernel allocations in kernel zone only

  panel:
   - OSD070T1718-19TS panel support
   - panel-tpo-td028ttec1 backlight support
   - Ronbo RB070D30 MIPI/DSI
   - Feiyang FY07024DI26A30-D MIPI-DSI panel
   - Rocktech jh057n00900 MIPI-DSI panel

  i915:
   - Comet Lake (Gen9) PCI IDs
   - Updated Icelake PCI IDs
   - Elkhartlake (Gen11) support
   - DP MST property addtions
   - plane and watermark fixes
   - Icelake port sync and VEBOX disable fixes
   - struct_mutex usage reduction
   - Icelake gamma fix
   - GuC reset fixes
   - make mmap more asynchronous
   - sound display power well race fixes
   - DDI/MIPI-DSI clocks for Icelake
   - Icelake RPS frequency changing support
   - Icelake workarounds

  amdgpu:
   - Use HMM for userptr
   - vega20 experimental smu11 support
   - RAS support for vega20
   - BACO support for vega12 + fixes for vega20
   - reworked IH interrupt handling
   - amdkfd RAS support
   - Freesync improvements
   - initial timeline sync object support
   - DC Z ordering fixes
   - NV12 planes support
   - colorspace properties for planes=
   - eDP opts if eDP already initialized

  nouveau:
   - misc fixes

  etnaviv:
   - misc fixes

  msm:
   - GPU zap shader support expansion
   - robustness ABI addition

  exynos:
   - Logging cleanups

  tegra:
   - Shared reset fix
   - CPU cache maintenance fix

  cirrus:
   - driver rewritten using simple helpers

  meson:
   - G12A support

  vmwgfx:
   - Resource dirtying management improvements
   - Userspace logging improvements

  virtio:
   - PRIME fixes

  rockchip:
   - rk3066 hdmi support

  sun4i:
   - DSI burst mode support

  vc4:
   - load tracker to detect underflow

  v3d:
   - v3d v4.2 support

  malidp:
   - initial Mali D71 support in komeda driver

  tfp410:
   - omap related improvement

  omapdrm:
   - drm bridge/panel support
   - drop some omap specific panels

  rcar-du:
   - Display writeback support"

* tag 'drm-next-2019-05-09' of git://anongit.freedesktop.org/drm/drm: (1507 commits)
  drm/msm/a6xx: No zap shader is not an error
  drm/cma-helper: Fix drm_gem_cma_free_object()
  drm: Fix timestamp docs for variable refresh properties.
  drm/komeda: Mark the local functions as static
  drm/komeda: Fixed warning: Function parameter or member not described
  drm/komeda: Expose bus_width to Komeda-CORE
  drm/komeda: Add sysfs attribute: core_id and config_id
  drm: add non-desktop quirk for Valve HMDs
  drm/panfrost: Show stored feature registers
  drm/panfrost: Don't scream about deferred probe
  drm/panfrost: Disable PM on probe failure
  drm/panfrost: Set DMA masks earlier
  drm/panfrost: Add sanity checks to submit IOCTL
  drm/etnaviv: initialize idle mask before querying the HW db
  drm: introduce a capability flag for syncobj timeline support
  drm: report consistent errors when checking syncobj capibility
  drm/nouveau/nouveau: forward error generated while resuming objects tree
  drm/nouveau/fb/ramgk104: fix spelling mistake "sucessfully" -> "successfully"
  drm/nouveau/i2c: Disable i2c bus access after ->fini()
  drm/nouveau: Remove duplicate ACPI_VIDEO_NOTIFY_PROBE definition
  ...

1 files changed, 373 insertions, 248 deletions

diff --git a/drivers/gpu/drm/i915/i915_reset.c b/drivers/gpu/drm/i915/i915_reset.c
index 0e0ddf2e6815..677d59304e78 100644
--- a/drivers/gpu/drm/i915/i915_reset.c
+++ b/drivers/gpu/drm/i915/i915_reset.c
@@ -18,28 +18,39 @@
 /* XXX How to handle concurrent GGTT updates using tiling registers? */
 #define RESET_UNDER_STOP_MACHINE 0
 
+static void rmw_set(struct intel_uncore *uncore, i915_reg_t reg, u32 set)
+{
+	intel_uncore_rmw(uncore, reg, 0, set);
+}
+
+static void rmw_clear(struct intel_uncore *uncore, i915_reg_t reg, u32 clr)
+{
+	intel_uncore_rmw(uncore, reg, clr, 0);
+}
+
+static void rmw_set_fw(struct intel_uncore *uncore, i915_reg_t reg, u32 set)
+{
+	intel_uncore_rmw_fw(uncore, reg, 0, set);
+}
+
+static void rmw_clear_fw(struct intel_uncore *uncore, i915_reg_t reg, u32 clr)
+{
+	intel_uncore_rmw_fw(uncore, reg, clr, 0);
+}
+
 static void engine_skip_context(struct i915_request *rq)
 {
 	struct intel_engine_cs *engine = rq->engine;
 	struct i915_gem_context *hung_ctx = rq->gem_context;
-	struct i915_timeline *timeline = rq->timeline;
 
 	lockdep_assert_held(&engine->timeline.lock);
-	GEM_BUG_ON(timeline == &engine->timeline);
-
-	spin_lock(&timeline->lock);
-
-	if (i915_request_is_active(rq)) {
-		list_for_each_entry_continue(rq,
-					     &engine->timeline.requests, link)
-			if (rq->gem_context == hung_ctx)
-				i915_request_skip(rq, -EIO);
-	}
 
-	list_for_each_entry(rq, &timeline->requests, link)
-		i915_request_skip(rq, -EIO);
+	if (!i915_request_is_active(rq))
+		return;
 
-	spin_unlock(&timeline->lock);
+	list_for_each_entry_continue(rq, &engine->timeline.requests, link)
+		if (rq->gem_context == hung_ctx)
+			i915_request_skip(rq, -EIO);
 }
 
 static void client_mark_guilty(struct drm_i915_file_private *file_priv,
@@ -68,23 +79,29 @@ static void client_mark_guilty(struct drm_i915_file_private *file_priv,
 
 static bool context_mark_guilty(struct i915_gem_context *ctx)
 {
-	unsigned int score;
-	bool banned, bannable;
+	unsigned long prev_hang;
+	bool banned;
+	int i;
 
 	atomic_inc(&ctx->guilty_count);
 
-	bannable = i915_gem_context_is_bannable(ctx);
-	score = atomic_add_return(CONTEXT_SCORE_GUILTY, &ctx->ban_score);
-	banned = score >= CONTEXT_SCORE_BAN_THRESHOLD;
-
-	/* Cool contexts don't accumulate client ban score */
-	if (!bannable)
+	/* Cool contexts are too cool to be banned! (Used for reset testing.) */
+	if (!i915_gem_context_is_bannable(ctx))
 		return false;
 
+	/* Record the timestamp for the last N hangs */
+	prev_hang = ctx->hang_timestamp[0];
+	for (i = 0; i < ARRAY_SIZE(ctx->hang_timestamp) - 1; i++)
+		ctx->hang_timestamp[i] = ctx->hang_timestamp[i + 1];
+	ctx->hang_timestamp[i] = jiffies;
+
+	/* If we have hung N+1 times in rapid succession, we ban the context! */
+	banned = !i915_gem_context_is_recoverable(ctx);
+	if (time_before(jiffies, prev_hang + CONTEXT_FAST_HANG_JIFFIES))
+		banned = true;
 	if (banned) {
-		DRM_DEBUG_DRIVER("context %s: guilty %d, score %u, banned\n",
-				 ctx->name, atomic_read(&ctx->guilty_count),
-				 score);
+		DRM_DEBUG_DRIVER("context %s: guilty %d, banned\n",
+				 ctx->name, atomic_read(&ctx->guilty_count));
 		i915_gem_context_set_banned(ctx);
 	}
 
@@ -101,6 +118,12 @@ static void context_mark_innocent(struct i915_gem_context *ctx)
 
 void i915_reset_request(struct i915_request *rq, bool guilty)
 {
+	GEM_TRACE("%s rq=%llx:%lld, guilty? %s\n",
+		  rq->engine->name,
+		  rq->fence.context,
+		  rq->fence.seqno,
+		  yesno(guilty));
+
 	lockdep_assert_held(&rq->engine->timeline.lock);
 	GEM_BUG_ON(i915_request_completed(rq));
 
@@ -116,38 +139,43 @@ void i915_reset_request(struct i915_request *rq, bool guilty)
 
 static void gen3_stop_engine(struct intel_engine_cs *engine)
 {
-	struct drm_i915_private *dev_priv = engine->i915;
+	struct intel_uncore *uncore = engine->uncore;
 	const u32 base = engine->mmio_base;
 
+	GEM_TRACE("%s\n", engine->name);
+
 	if (intel_engine_stop_cs(engine))
-		DRM_DEBUG_DRIVER("%s: timed out on STOP_RING\n", engine->name);
+		GEM_TRACE("%s: timed out on STOP_RING\n", engine->name);
 
-	I915_WRITE_FW(RING_HEAD(base), I915_READ_FW(RING_TAIL(base)));
-	POSTING_READ_FW(RING_HEAD(base)); /* paranoia */
+	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 */
 
-	I915_WRITE_FW(RING_HEAD(base), 0);
-	I915_WRITE_FW(RING_TAIL(base), 0);
-	POSTING_READ_FW(RING_TAIL(base));
+	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 */
-	I915_WRITE_FW(RING_CTL(base), 0);
+	intel_uncore_write_fw(uncore, RING_CTL(base), 0);
 
 	/* Check acts as a post */
-	if (I915_READ_FW(RING_HEAD(base)) != 0)
-		DRM_DEBUG_DRIVER("%s: ring head not parked\n",
-				 engine->name);
+	if (intel_uncore_read_fw(uncore, RING_HEAD(base)))
+		GEM_TRACE("%s: ring head [%x] not parked\n",
+			  engine->name,
+			  intel_uncore_read_fw(uncore, RING_HEAD(base)));
 }
 
 static void i915_stop_engines(struct drm_i915_private *i915,
-			      unsigned int engine_mask)
+			      intel_engine_mask_t engine_mask)
 {
 	struct intel_engine_cs *engine;
-	enum intel_engine_id id;
+	intel_engine_mask_t tmp;
 
 	if (INTEL_GEN(i915) < 3)
 		return;
 
-	for_each_engine_masked(engine, i915, engine_mask, id)
+	for_each_engine_masked(engine, i915, engine_mask, tmp)
 		gen3_stop_engine(engine);
 }
 
@@ -160,7 +188,7 @@ static bool i915_in_reset(struct pci_dev *pdev)
 }
 
 static int i915_do_reset(struct drm_i915_private *i915,
-			 unsigned int engine_mask,
+			 intel_engine_mask_t engine_mask,
 			 unsigned int retry)
 {
 	struct pci_dev *pdev = i915->drm.pdev;
@@ -189,7 +217,7 @@ static bool g4x_reset_complete(struct pci_dev *pdev)
 }
 
 static int g33_do_reset(struct drm_i915_private *i915,
-			unsigned int engine_mask,
+			intel_engine_mask_t engine_mask,
 			unsigned int retry)
 {
 	struct pci_dev *pdev = i915->drm.pdev;
@@ -198,17 +226,17 @@ static int g33_do_reset(struct drm_i915_private *i915,
 	return wait_for_atomic(g4x_reset_complete(pdev), 50);
 }
 
-static int g4x_do_reset(struct drm_i915_private *dev_priv,
-			unsigned int engine_mask,
+static int g4x_do_reset(struct drm_i915_private *i915,
+			intel_engine_mask_t engine_mask,
 			unsigned int retry)
 {
-	struct pci_dev *pdev = dev_priv->drm.pdev;
+	struct pci_dev *pdev = i915->drm.pdev;
+	struct intel_uncore *uncore = &i915->uncore;
 	int ret;
 
 	/* WaVcpClkGateDisableForMediaReset:ctg,elk */
-	I915_WRITE_FW(VDECCLK_GATE_D,
-		      I915_READ(VDECCLK_GATE_D) | VCP_UNIT_CLOCK_GATE_DISABLE);
-	POSTING_READ_FW(VDECCLK_GATE_D);
+	rmw_set_fw(uncore, VDECCLK_GATE_D, VCP_UNIT_CLOCK_GATE_DISABLE);
+	intel_uncore_posting_read_fw(uncore, VDECCLK_GATE_D);
 
 	pci_write_config_byte(pdev, I915_GDRST,
 			      GRDOM_MEDIA | GRDOM_RESET_ENABLE);
@@ -229,21 +257,22 @@ static int g4x_do_reset(struct drm_i915_private *dev_priv,
 out:
 	pci_write_config_byte(pdev, I915_GDRST, 0);
 
-	I915_WRITE_FW(VDECCLK_GATE_D,
-		      I915_READ(VDECCLK_GATE_D) & ~VCP_UNIT_CLOCK_GATE_DISABLE);
-	POSTING_READ_FW(VDECCLK_GATE_D);
+	rmw_clear_fw(uncore, VDECCLK_GATE_D, VCP_UNIT_CLOCK_GATE_DISABLE);
+	intel_uncore_posting_read_fw(uncore, VDECCLK_GATE_D);
 
 	return ret;
 }
 
-static int ironlake_do_reset(struct drm_i915_private *dev_priv,
-			     unsigned int engine_mask,
+static int ironlake_do_reset(struct drm_i915_private *i915,
+			     intel_engine_mask_t engine_mask,
 			     unsigned int retry)
 {
+	struct intel_uncore *uncore = &i915->uncore;
 	int ret;
 
-	I915_WRITE_FW(ILK_GDSR, ILK_GRDOM_RENDER | ILK_GRDOM_RESET_ENABLE);
-	ret = __intel_wait_for_register_fw(dev_priv, ILK_GDSR,
+	intel_uncore_write_fw(uncore, ILK_GDSR,
+			      ILK_GRDOM_RENDER | ILK_GRDOM_RESET_ENABLE);
+	ret = __intel_wait_for_register_fw(uncore, ILK_GDSR,
 					   ILK_GRDOM_RESET_ENABLE, 0,
 					   5000, 0,
 					   NULL);
@@ -252,8 +281,9 @@ static int ironlake_do_reset(struct drm_i915_private *dev_priv,
 		goto out;
 	}
 
-	I915_WRITE_FW(ILK_GDSR, ILK_GRDOM_MEDIA | ILK_GRDOM_RESET_ENABLE);
-	ret = __intel_wait_for_register_fw(dev_priv, ILK_GDSR,
+	intel_uncore_write_fw(uncore, ILK_GDSR,
+			      ILK_GRDOM_MEDIA | ILK_GRDOM_RESET_ENABLE);
+	ret = __intel_wait_for_register_fw(uncore, ILK_GDSR,
 					   ILK_GRDOM_RESET_ENABLE, 0,
 					   5000, 0,
 					   NULL);
@@ -263,15 +293,16 @@ static int ironlake_do_reset(struct drm_i915_private *dev_priv,
 	}
 
 out:
-	I915_WRITE_FW(ILK_GDSR, 0);
-	POSTING_READ_FW(ILK_GDSR);
+	intel_uncore_write_fw(uncore, ILK_GDSR, 0);
+	intel_uncore_posting_read_fw(uncore, ILK_GDSR);
 	return ret;
 }
 
 /* Reset the hardware domains (GENX_GRDOM_*) specified by mask */
-static int gen6_hw_domain_reset(struct drm_i915_private *dev_priv,
+static int gen6_hw_domain_reset(struct drm_i915_private *i915,
 				u32 hw_domain_mask)
 {
+	struct intel_uncore *uncore = &i915->uncore;
 	int err;
 
 	/*
@@ -279,10 +310,10 @@ static int gen6_hw_domain_reset(struct drm_i915_private *dev_priv,
 	 * for fifo space for the write or forcewake the chip for
 	 * the read
 	 */
-	I915_WRITE_FW(GEN6_GDRST, hw_domain_mask);
+	intel_uncore_write_fw(uncore, GEN6_GDRST, hw_domain_mask);
 
 	/* Wait for the device to ack the reset requests */
-	err = __intel_wait_for_register_fw(dev_priv,
+	err = __intel_wait_for_register_fw(uncore,
 					   GEN6_GDRST, hw_domain_mask, 0,
 					   500, 0,
 					   NULL);
@@ -294,36 +325,38 @@ static int gen6_hw_domain_reset(struct drm_i915_private *dev_priv,
 }
 
 static int gen6_reset_engines(struct drm_i915_private *i915,
-			      unsigned int engine_mask,
+			      intel_engine_mask_t engine_mask,
 			      unsigned int retry)
 {
 	struct intel_engine_cs *engine;
-	const u32 hw_engine_mask[I915_NUM_ENGINES] = {
-		[RCS] = GEN6_GRDOM_RENDER,
-		[BCS] = GEN6_GRDOM_BLT,
-		[VCS] = GEN6_GRDOM_MEDIA,
-		[VCS2] = GEN8_GRDOM_MEDIA2,
-		[VECS] = GEN6_GRDOM_VECS,
+	const u32 hw_engine_mask[] = {
+		[RCS0]  = GEN6_GRDOM_RENDER,
+		[BCS0]  = GEN6_GRDOM_BLT,
+		[VCS0]  = GEN6_GRDOM_MEDIA,
+		[VCS1]  = GEN8_GRDOM_MEDIA2,
+		[VECS0] = GEN6_GRDOM_VECS,
 	};
 	u32 hw_mask;
 
 	if (engine_mask == ALL_ENGINES) {
 		hw_mask = GEN6_GRDOM_FULL;
 	} else {
-		unsigned int tmp;
+		intel_engine_mask_t tmp;
 
 		hw_mask = 0;
-		for_each_engine_masked(engine, i915, engine_mask, tmp)
+		for_each_engine_masked(engine, i915, engine_mask, tmp) {
+			GEM_BUG_ON(engine->id >= ARRAY_SIZE(hw_engine_mask));
 			hw_mask |= hw_engine_mask[engine->id];
+		}
 	}
 
 	return gen6_hw_domain_reset(i915, hw_mask);
 }
 
-static u32 gen11_lock_sfc(struct drm_i915_private *dev_priv,
-			  struct intel_engine_cs *engine)
+static u32 gen11_lock_sfc(struct intel_engine_cs *engine)
 {
-	u8 vdbox_sfc_access = RUNTIME_INFO(dev_priv)->vdbox_sfc_access;
+	struct intel_uncore *uncore = engine->uncore;
+	u8 vdbox_sfc_access = RUNTIME_INFO(engine->i915)->vdbox_sfc_access;
 	i915_reg_t sfc_forced_lock, sfc_forced_lock_ack;
 	u32 sfc_forced_lock_bit, sfc_forced_lock_ack_bit;
 	i915_reg_t sfc_usage;
@@ -370,10 +403,9 @@ static u32 gen11_lock_sfc(struct drm_i915_private *dev_priv,
 	 * ends up being locked to the engine we want to reset, we have to reset
 	 * it as well (we will unlock it once the reset sequence is completed).
 	 */
-	I915_WRITE_FW(sfc_forced_lock,
-		      I915_READ_FW(sfc_forced_lock) | sfc_forced_lock_bit);
+	rmw_set_fw(uncore, sfc_forced_lock, sfc_forced_lock_bit);
 
-	if (__intel_wait_for_register_fw(dev_priv,
+	if (__intel_wait_for_register_fw(uncore,
 					 sfc_forced_lock_ack,
 					 sfc_forced_lock_ack_bit,
 					 sfc_forced_lock_ack_bit,
@@ -382,16 +414,16 @@ static u32 gen11_lock_sfc(struct drm_i915_private *dev_priv,
 		return 0;
 	}
 
-	if (I915_READ_FW(sfc_usage) & sfc_usage_bit)
+	if (intel_uncore_read_fw(uncore, sfc_usage) & sfc_usage_bit)
 		return sfc_reset_bit;
 
 	return 0;
 }
 
-static void gen11_unlock_sfc(struct drm_i915_private *dev_priv,
-			     struct intel_engine_cs *engine)
+static void gen11_unlock_sfc(struct intel_engine_cs *engine)
 {
-	u8 vdbox_sfc_access = RUNTIME_INFO(dev_priv)->vdbox_sfc_access;
+	struct intel_uncore *uncore = engine->uncore;
+	u8 vdbox_sfc_access = RUNTIME_INFO(engine->i915)->vdbox_sfc_access;
 	i915_reg_t sfc_forced_lock;
 	u32 sfc_forced_lock_bit;
 
@@ -413,38 +445,36 @@ static void gen11_unlock_sfc(struct drm_i915_private *dev_priv,
 		return;
 	}
 
-	I915_WRITE_FW(sfc_forced_lock,
-		      I915_READ_FW(sfc_forced_lock) & ~sfc_forced_lock_bit);
+	rmw_clear_fw(uncore, sfc_forced_lock, sfc_forced_lock_bit);
 }
 
 static int gen11_reset_engines(struct drm_i915_private *i915,
-			       unsigned int engine_mask,
+			       intel_engine_mask_t engine_mask,
 			       unsigned int retry)
 {
-	const u32 hw_engine_mask[I915_NUM_ENGINES] = {
-		[RCS] = GEN11_GRDOM_RENDER,
-		[BCS] = GEN11_GRDOM_BLT,
-		[VCS] = GEN11_GRDOM_MEDIA,
-		[VCS2] = GEN11_GRDOM_MEDIA2,
-		[VCS3] = GEN11_GRDOM_MEDIA3,
-		[VCS4] = GEN11_GRDOM_MEDIA4,
-		[VECS] = GEN11_GRDOM_VECS,
-		[VECS2] = GEN11_GRDOM_VECS2,
+	const u32 hw_engine_mask[] = {
+		[RCS0]  = GEN11_GRDOM_RENDER,
+		[BCS0]  = GEN11_GRDOM_BLT,
+		[VCS0]  = GEN11_GRDOM_MEDIA,
+		[VCS1]  = GEN11_GRDOM_MEDIA2,
+		[VCS2]  = GEN11_GRDOM_MEDIA3,
+		[VCS3]  = GEN11_GRDOM_MEDIA4,
+		[VECS0] = GEN11_GRDOM_VECS,
+		[VECS1] = GEN11_GRDOM_VECS2,
 	};
 	struct intel_engine_cs *engine;
-	unsigned int tmp;
+	intel_engine_mask_t tmp;
 	u32 hw_mask;
 	int ret;
 
-	BUILD_BUG_ON(VECS2 + 1 != I915_NUM_ENGINES);
-
 	if (engine_mask == ALL_ENGINES) {
 		hw_mask = GEN11_GRDOM_FULL;
 	} else {
 		hw_mask = 0;
 		for_each_engine_masked(engine, i915, engine_mask, tmp) {
+			GEM_BUG_ON(engine->id >= ARRAY_SIZE(hw_engine_mask));
 			hw_mask |= hw_engine_mask[engine->id];
-			hw_mask |= gen11_lock_sfc(i915, engine);
+			hw_mask |= gen11_lock_sfc(engine);
 		}
 	}
 
@@ -452,46 +482,62 @@ static int gen11_reset_engines(struct drm_i915_private *i915,
 
 	if (engine_mask != ALL_ENGINES)
 		for_each_engine_masked(engine, i915, engine_mask, tmp)
-			gen11_unlock_sfc(i915, engine);
+			gen11_unlock_sfc(engine);
 
 	return ret;
 }
 
 static int gen8_engine_reset_prepare(struct intel_engine_cs *engine)
 {
-	struct drm_i915_private *dev_priv = engine->i915;
+	struct intel_uncore *uncore = engine->uncore;
+	const i915_reg_t reg = RING_RESET_CTL(engine->mmio_base);
+	u32 request, mask, ack;
 	int ret;
 
-	I915_WRITE_FW(RING_RESET_CTL(engine->mmio_base),
-		      _MASKED_BIT_ENABLE(RESET_CTL_REQUEST_RESET));
+	ack = intel_uncore_read_fw(uncore, reg);
+	if (ack & RESET_CTL_CAT_ERROR) {
+		/*
+		 * For catastrophic errors, ready-for-reset sequence
+		 * needs to be bypassed: HAS#396813
+		 */
+		request = RESET_CTL_CAT_ERROR;
+		mask = RESET_CTL_CAT_ERROR;
+
+		/* Catastrophic errors need to be cleared by HW */
+		ack = 0;
+	} else if (!(ack & RESET_CTL_READY_TO_RESET)) {
+		request = RESET_CTL_REQUEST_RESET;
+		mask = RESET_CTL_READY_TO_RESET;
+		ack = RESET_CTL_READY_TO_RESET;
+	} else {
+		return 0;
+	}
 
-	ret = __intel_wait_for_register_fw(dev_priv,
-					   RING_RESET_CTL(engine->mmio_base),
-					   RESET_CTL_READY_TO_RESET,
-					   RESET_CTL_READY_TO_RESET,
-					   700, 0,
-					   NULL);
+	intel_uncore_write_fw(uncore, reg, _MASKED_BIT_ENABLE(request));
+	ret = __intel_wait_for_register_fw(uncore, reg, mask, ack,
+					   700, 0, NULL);
 	if (ret)
-		DRM_ERROR("%s: reset request timeout\n", engine->name);
+		DRM_ERROR("%s reset request timed out: {request: %08x, RESET_CTL: %08x}\n",
+			  engine->name, request,
+			  intel_uncore_read_fw(uncore, reg));
 
 	return ret;
 }
 
 static void gen8_engine_reset_cancel(struct intel_engine_cs *engine)
 {
-	struct drm_i915_private *dev_priv = engine->i915;
-
-	I915_WRITE_FW(RING_RESET_CTL(engine->mmio_base),
-		      _MASKED_BIT_DISABLE(RESET_CTL_REQUEST_RESET));
+	intel_uncore_write_fw(engine->uncore,
+			      RING_RESET_CTL(engine->mmio_base),
+			      _MASKED_BIT_DISABLE(RESET_CTL_REQUEST_RESET));
 }
 
 static int gen8_reset_engines(struct drm_i915_private *i915,
-			      unsigned int engine_mask,
+			      intel_engine_mask_t engine_mask,
 			      unsigned int retry)
 {
 	struct intel_engine_cs *engine;
 	const bool reset_non_ready = retry >= 1;
-	unsigned int tmp;
+	intel_engine_mask_t tmp;
 	int ret;
 
 	for_each_engine_masked(engine, i915, engine_mask, tmp) {
@@ -527,14 +573,11 @@ skip_reset:
 }
 
 typedef int (*reset_func)(struct drm_i915_private *,
-			  unsigned int engine_mask,
+			  intel_engine_mask_t engine_mask,
 			  unsigned int retry);
 
 static reset_func intel_get_gpu_reset(struct drm_i915_private *i915)
 {
-	if (!i915_modparams.reset)
-		return NULL;
-
 	if (INTEL_GEN(i915) >= 8)
 		return gen8_reset_engines;
 	else if (INTEL_GEN(i915) >= 6)
@@ -551,7 +594,8 @@ static reset_func intel_get_gpu_reset(struct drm_i915_private *i915)
 		return NULL;
 }
 
-int intel_gpu_reset(struct drm_i915_private *i915, unsigned int engine_mask)
+int intel_gpu_reset(struct drm_i915_private *i915,
+		    intel_engine_mask_t engine_mask)
 {
 	const int retries = engine_mask == ALL_ENGINES ? RESET_MAX_RETRIES : 1;
 	reset_func reset;
@@ -566,7 +610,7 @@ int intel_gpu_reset(struct drm_i915_private *i915, unsigned int engine_mask)
 	 * If the power well sleeps during the reset, the reset
 	 * request may be dropped and never completes (causing -EIO).
 	 */
-	intel_uncore_forcewake_get(i915, FORCEWAKE_ALL);
+	intel_uncore_forcewake_get(&i915->uncore, FORCEWAKE_ALL);
 	for (retry = 0; ret == -ETIMEDOUT && retry < retries; retry++) {
 		/*
 		 * We stop engines, otherwise we might get failed reset and a
@@ -582,14 +626,15 @@ int intel_gpu_reset(struct drm_i915_private *i915, unsigned int engine_mask)
 		 *
 		 * FIXME: Wa for more modern gens needs to be validated
 		 */
-		i915_stop_engines(i915, engine_mask);
+		if (retry)
+			i915_stop_engines(i915, engine_mask);
 
 		GEM_TRACE("engine_mask=%x\n", engine_mask);
 		preempt_disable();
 		ret = reset(i915, engine_mask, retry);
 		preempt_enable();
 	}
-	intel_uncore_forcewake_put(i915, FORCEWAKE_ALL);
+	intel_uncore_forcewake_put(&i915->uncore, FORCEWAKE_ALL);
 
 	return ret;
 }
@@ -599,6 +644,9 @@ bool intel_has_gpu_reset(struct drm_i915_private *i915)
 	if (USES_GUC(i915))
 		return false;
 
+	if (!i915_modparams.reset)
+		return NULL;
+
 	return intel_get_gpu_reset(i915);
 }
 
@@ -615,9 +663,9 @@ int intel_reset_guc(struct drm_i915_private *i915)
 
 	GEM_BUG_ON(!HAS_GUC(i915));
 
-	intel_uncore_forcewake_get(i915, FORCEWAKE_ALL);
+	intel_uncore_forcewake_get(&i915->uncore, FORCEWAKE_ALL);
 	ret = gen6_hw_domain_reset(i915, guc_domain);
-	intel_uncore_forcewake_put(i915, FORCEWAKE_ALL);
+	intel_uncore_forcewake_put(&i915->uncore, FORCEWAKE_ALL);
 
 	return ret;
 }
@@ -635,10 +683,36 @@ static void reset_prepare_engine(struct intel_engine_cs *engine)
 	 * written to the powercontext is undefined and so we may lose
 	 * GPU state upon resume, i.e. fail to restart after a reset.
 	 */
-	intel_uncore_forcewake_get(engine->i915, FORCEWAKE_ALL);
+	intel_uncore_forcewake_get(engine->uncore, FORCEWAKE_ALL);
 	engine->reset.prepare(engine);
 }
 
+static void revoke_mmaps(struct drm_i915_private *i915)
+{
+	int i;
+
+	for (i = 0; i < i915->num_fence_regs; i++) {
+		struct drm_vma_offset_node *node;
+		struct i915_vma *vma;
+		u64 vma_offset;
+
+		vma = READ_ONCE(i915->fence_regs[i].vma);
+		if (!vma)
+			continue;
+
+		if (!i915_vma_has_userfault(vma))
+			continue;
+
+		GEM_BUG_ON(vma->fence != &i915->fence_regs[i]);
+		node = &vma->obj->base.vma_node;
+		vma_offset = vma->ggtt_view.partial.offset << PAGE_SHIFT;
+		unmap_mapping_range(i915->drm.anon_inode->i_mapping,
+				    drm_vma_node_offset_addr(node) + vma_offset,
+				    vma->size,
+				    1);
+	}
+}
+
 static void reset_prepare(struct drm_i915_private *i915)
 {
 	struct intel_engine_cs *engine;
@@ -647,10 +721,16 @@ static void reset_prepare(struct drm_i915_private *i915)
 	for_each_engine(engine, i915, id)
 		reset_prepare_engine(engine);
 
-	intel_uc_sanitize(i915);
+	intel_uc_reset_prepare(i915);
+}
+
+static void gt_revoke(struct drm_i915_private *i915)
+{
+	revoke_mmaps(i915);
 }
 
-static int gt_reset(struct drm_i915_private *i915, unsigned int stalled_mask)
+static int gt_reset(struct drm_i915_private *i915,
+		    intel_engine_mask_t stalled_mask)
 {
 	struct intel_engine_cs *engine;
 	enum intel_engine_id id;
@@ -665,7 +745,7 @@ static int gt_reset(struct drm_i915_private *i915, unsigned int stalled_mask)
 		return err;
 
 	for_each_engine(engine, i915, id)
-		intel_engine_reset(engine, stalled_mask & ENGINE_MASK(id));
+		intel_engine_reset(engine, stalled_mask & engine->mask);
 
 	i915_gem_restore_fences(i915);
 
@@ -675,7 +755,7 @@ static int gt_reset(struct drm_i915_private *i915, unsigned int stalled_mask)
 static void reset_finish_engine(struct intel_engine_cs *engine)
 {
 	engine->reset.finish(engine);
-	intel_uncore_forcewake_put(engine->i915, FORCEWAKE_ALL);
+	intel_uncore_forcewake_put(engine->uncore, FORCEWAKE_ALL);
 }
 
 struct i915_gpu_restart {
@@ -722,8 +802,10 @@ static void reset_finish(struct drm_i915_private *i915)
 	struct intel_engine_cs *engine;
 	enum intel_engine_id id;
 
-	for_each_engine(engine, i915, id)
+	for_each_engine(engine, i915, id) {
 		reset_finish_engine(engine);
+		intel_engine_signal_breadcrumbs(engine);
+	}
 }
 
 static void reset_restart(struct drm_i915_private *i915)
@@ -761,23 +843,19 @@ static void nop_submit_request(struct i915_request *request)
 	spin_lock_irqsave(&engine->timeline.lock, flags);
 	__i915_request_submit(request);
 	i915_request_mark_complete(request);
-	intel_engine_write_global_seqno(engine, request->global_seqno);
 	spin_unlock_irqrestore(&engine->timeline.lock, flags);
 
 	intel_engine_queue_breadcrumbs(engine);
 }
 
-void i915_gem_set_wedged(struct drm_i915_private *i915)
+static void __i915_gem_set_wedged(struct drm_i915_private *i915)
 {
 	struct i915_gpu_error *error = &i915->gpu_error;
 	struct intel_engine_cs *engine;
 	enum intel_engine_id id;
 
-	mutex_lock(&error->wedge_mutex);
-	if (test_bit(I915_WEDGED, &error->flags)) {
-		mutex_unlock(&error->wedge_mutex);
+	if (test_bit(I915_WEDGED, &error->flags))
 		return;
-	}
 
 	if (GEM_SHOW_DEBUG() && !intel_engines_are_idle(i915)) {
 		struct drm_printer p = drm_debug_printer(__func__);
@@ -793,11 +871,10 @@ void i915_gem_set_wedged(struct drm_i915_private *i915)
 	 * rolling the global seqno forward (since this would complete requests
 	 * for which we haven't set the fence error to EIO yet).
 	 */
-	for_each_engine(engine, i915, id)
-		reset_prepare_engine(engine);
+	reset_prepare(i915);
 
 	/* Even if the GPU reset fails, it should still stop the engines */
-	if (INTEL_GEN(i915) >= 5)
+	if (!INTEL_INFO(i915)->gpu_reset_clobbers_display)
 		intel_gpu_reset(i915, ALL_ENGINES);
 
 	for_each_engine(engine, i915, id) {
@@ -811,31 +888,35 @@ void i915_gem_set_wedged(struct drm_i915_private *i915)
 	 * either this call here to intel_engine_write_global_seqno, or the one
 	 * in nop_submit_request.
 	 */
-	synchronize_rcu();
+	synchronize_rcu_expedited();
 
 	/* Mark all executing requests as skipped */
 	for_each_engine(engine, i915, id)
 		engine->cancel_requests(engine);
 
-	for_each_engine(engine, i915, id) {
-		reset_finish_engine(engine);
-		intel_engine_signal_breadcrumbs(engine);
-	}
+	reset_finish(i915);
 
 	smp_mb__before_atomic();
 	set_bit(I915_WEDGED, &error->flags);
 
 	GEM_TRACE("end\n");
-	mutex_unlock(&error->wedge_mutex);
+}
 
-	wake_up_all(&error->reset_queue);
+void i915_gem_set_wedged(struct drm_i915_private *i915)
+{
+	struct i915_gpu_error *error = &i915->gpu_error;
+	intel_wakeref_t wakeref;
+
+	mutex_lock(&error->wedge_mutex);
+	with_intel_runtime_pm(i915, wakeref)
+		__i915_gem_set_wedged(i915);
+	mutex_unlock(&error->wedge_mutex);
 }
 
-bool i915_gem_unset_wedged(struct drm_i915_private *i915)
+static bool __i915_gem_unset_wedged(struct drm_i915_private *i915)
 {
 	struct i915_gpu_error *error = &i915->gpu_error;
 	struct i915_timeline *tl;
-	bool ret = false;
 
 	if (!test_bit(I915_WEDGED, &error->flags))
 		return true;
@@ -843,8 +924,6 @@ bool i915_gem_unset_wedged(struct drm_i915_private *i915)
 	if (!i915->gt.scratch) /* Never full initialised, recovery impossible */
 		return false;
 
-	mutex_lock(&error->wedge_mutex);
-
 	GEM_TRACE("start\n");
 
 	/*
@@ -860,30 +939,20 @@ bool i915_gem_unset_wedged(struct drm_i915_private *i915)
 	mutex_lock(&i915->gt.timelines.mutex);
 	list_for_each_entry(tl, &i915->gt.timelines.active_list, link) {
 		struct i915_request *rq;
-		long timeout;
 
 		rq = i915_active_request_get_unlocked(&tl->last_request);
 		if (!rq)
 			continue;
 
 		/*
-		 * We can't use our normal waiter as we want to
-		 * avoid recursively trying to handle the current
-		 * reset. The basic dma_fence_default_wait() installs
-		 * a callback for dma_fence_signal(), which is
-		 * triggered by our nop handler (indirectly, the
-		 * callback enables the signaler thread which is
-		 * woken by the nop_submit_request() advancing the seqno
-		 * and when the seqno passes the fence, the signaler
-		 * then signals the fence waking us up).
+		 * All internal dependencies (i915_requests) will have
+		 * been flushed by the set-wedge, but we may be stuck waiting
+		 * for external fences. These should all be capped to 10s
+		 * (I915_FENCE_TIMEOUT) so this wait should not be unbounded
+		 * in the worst case.
 		 */
-		timeout = dma_fence_default_wait(&rq->fence, true,
-						 MAX_SCHEDULE_TIMEOUT);
+		dma_fence_default_wait(&rq->fence, false, MAX_SCHEDULE_TIMEOUT);
 		i915_request_put(rq);
-		if (timeout < 0) {
-			mutex_unlock(&i915->gt.timelines.mutex);
-			goto unlock;
-		}
 	}
 	mutex_unlock(&i915->gt.timelines.mutex);
 
@@ -904,57 +973,38 @@ bool i915_gem_unset_wedged(struct drm_i915_private *i915)
 
 	smp_mb__before_atomic(); /* complete takeover before enabling execbuf */
 	clear_bit(I915_WEDGED, &i915->gpu_error.flags);
-	ret = true;
-unlock:
-	mutex_unlock(&i915->gpu_error.wedge_mutex);
 
-	return ret;
+	return true;
 }
 
-struct __i915_reset {
-	struct drm_i915_private *i915;
-	unsigned int stalled_mask;
-};
-
-static int __i915_reset__BKL(void *data)
+bool i915_gem_unset_wedged(struct drm_i915_private *i915)
 {
-	struct __i915_reset *arg = data;
-	int err;
+	struct i915_gpu_error *error = &i915->gpu_error;
+	bool result;
 
-	err = intel_gpu_reset(arg->i915, ALL_ENGINES);
-	if (err)
-		return err;
+	mutex_lock(&error->wedge_mutex);
+	result = __i915_gem_unset_wedged(i915);
+	mutex_unlock(&error->wedge_mutex);
 
-	return gt_reset(arg->i915, arg->stalled_mask);
+	return result;
 }
 
-#if RESET_UNDER_STOP_MACHINE
-/*
- * XXX An alternative to using stop_machine would be to park only the
- * processes that have a GGTT mmap. By remote parking the threads (SIGSTOP)
- * we should be able to prevent their memmory accesses via the lost fence
- * registers over the course of the reset without the potential recursive
- * of mutexes between the pagefault handler and reset.
- *
- * See igt/gem_mmap_gtt/hang
- */
-#define __do_reset(fn, arg) stop_machine(fn, arg, NULL)
-#else
-#define __do_reset(fn, arg) fn(arg)
-#endif
-
-static int do_reset(struct drm_i915_private *i915, unsigned int stalled_mask)
+static int do_reset(struct drm_i915_private *i915,
+		    intel_engine_mask_t stalled_mask)
 {
-	struct __i915_reset arg = { i915, stalled_mask };
 	int err, i;
 
-	err = __do_reset(__i915_reset__BKL, &arg);
+	gt_revoke(i915);
+
+	err = intel_gpu_reset(i915, ALL_ENGINES);
 	for (i = 0; err && i < RESET_MAX_RETRIES; i++) {
-		msleep(100);
-		err = __do_reset(__i915_reset__BKL, &arg);
+		msleep(10 * (i + 1));
+		err = intel_gpu_reset(i915, ALL_ENGINES);
 	}
+	if (err)
+		return err;
 
-	return err;
+	return gt_reset(i915, stalled_mask);
 }
 
 /**
@@ -966,8 +1016,6 @@ static int do_reset(struct drm_i915_private *i915, unsigned int stalled_mask)
  * Reset the chip.  Useful if a hang is detected. Marks the device as wedged
  * on failure.
  *
- * Caller must hold the struct_mutex.
- *
  * Procedure is fairly simple:
  *   - reset the chip using the reset reg
  *   - re-init context state
@@ -977,7 +1025,7 @@ static int do_reset(struct drm_i915_private *i915, unsigned int stalled_mask)
  *   - re-init display
  */
 void i915_reset(struct drm_i915_private *i915,
-		unsigned int stalled_mask,
+		intel_engine_mask_t stalled_mask,
 		const char *reason)
 {
 	struct i915_gpu_error *error = &i915->gpu_error;
@@ -990,7 +1038,7 @@ void i915_reset(struct drm_i915_private *i915,
 	GEM_BUG_ON(!test_bit(I915_RESET_BACKOFF, &error->flags));
 
 	/* Clear any previous failed attempts at recovery. Time to try again. */
-	if (!i915_gem_unset_wedged(i915))
+	if (!__i915_gem_unset_wedged(i915))
 		return;
 
 	if (reason)
@@ -1007,11 +1055,17 @@ void i915_reset(struct drm_i915_private *i915,
 		goto error;
 	}
 
+	if (INTEL_INFO(i915)->gpu_reset_clobbers_display)
+		intel_runtime_pm_disable_interrupts(i915);
+
 	if (do_reset(i915, stalled_mask)) {
 		dev_err(i915->drm.dev, "Failed to reset chip\n");
 		goto taint;
 	}
 
+	if (INTEL_INFO(i915)->gpu_reset_clobbers_display)
+		intel_runtime_pm_enable_interrupts(i915);
+
 	intel_overlay_reset(i915);
 
 	/*
@@ -1033,7 +1087,7 @@ void i915_reset(struct drm_i915_private *i915,
 
 finish:
 	reset_finish(i915);
-	if (!i915_terminally_wedged(error))
+	if (!__i915_wedged(error))
 		reset_restart(i915);
 	return;
 
@@ -1052,14 +1106,14 @@ taint:
 	 */
 	add_taint(TAINT_WARN, LOCKDEP_STILL_OK);
 error:
-	i915_gem_set_wedged(i915);
+	__i915_gem_set_wedged(i915);
 	goto finish;
 }
 
 static inline int intel_gt_reset_engine(struct drm_i915_private *i915,
 					struct intel_engine_cs *engine)
 {
-	return intel_gpu_reset(i915, intel_engine_flag(engine));
+	return intel_gpu_reset(i915, engine->mask);
 }
 
 /**
@@ -1144,7 +1198,12 @@ static void i915_reset_device(struct drm_i915_private *i915,
 	i915_wedge_on_timeout(&w, i915, 5 * HZ) {
 		intel_prepare_reset(i915);
 
+		/* Flush everyone using a resource about to be clobbered */
+		synchronize_srcu_expedited(&error->reset_backoff_srcu);
+
+		mutex_lock(&error->wedge_mutex);
 		i915_reset(i915, engine_mask, reason);
+		mutex_unlock(&error->wedge_mutex);
 
 		intel_finish_reset(i915);
 	}
@@ -1153,44 +1212,50 @@ static void i915_reset_device(struct drm_i915_private *i915,
 		kobject_uevent_env(kobj, KOBJ_CHANGE, reset_done_event);
 }
 
-void i915_clear_error_registers(struct drm_i915_private *dev_priv)
+static void clear_register(struct intel_uncore *uncore, i915_reg_t reg)
 {
+	intel_uncore_rmw(uncore, reg, 0, 0);
+}
+
+void i915_clear_error_registers(struct drm_i915_private *i915)
+{
+	struct intel_uncore *uncore = &i915->uncore;
 	u32 eir;
 
-	if (!IS_GEN(dev_priv, 2))
-		I915_WRITE(PGTBL_ER, I915_READ(PGTBL_ER));
+	if (!IS_GEN(i915, 2))
+		clear_register(uncore, PGTBL_ER);
 
-	if (INTEL_GEN(dev_priv) < 4)
-		I915_WRITE(IPEIR, I915_READ(IPEIR));
+	if (INTEL_GEN(i915) < 4)
+		clear_register(uncore, IPEIR(RENDER_RING_BASE));
 	else
-		I915_WRITE(IPEIR_I965, I915_READ(IPEIR_I965));
+		clear_register(uncore, IPEIR_I965);
 
-	I915_WRITE(EIR, I915_READ(EIR));
-	eir = I915_READ(EIR);
+	clear_register(uncore, EIR);
+	eir = intel_uncore_read(uncore, EIR);
 	if (eir) {
 		/*
 		 * some errors might have become stuck,
 		 * mask them.
 		 */
 		DRM_DEBUG_DRIVER("EIR stuck: 0x%08x, masking\n", eir);
-		I915_WRITE(EMR, I915_READ(EMR) | eir);
-		I915_WRITE(IIR, I915_MASTER_ERROR_INTERRUPT);
+		rmw_set(uncore, EMR, eir);
+		intel_uncore_write(uncore, GEN2_IIR,
+				   I915_MASTER_ERROR_INTERRUPT);
 	}
 
-	if (INTEL_GEN(dev_priv) >= 8) {
-		I915_WRITE(GEN8_RING_FAULT_REG,
-			   I915_READ(GEN8_RING_FAULT_REG) & ~RING_FAULT_VALID);
-		POSTING_READ(GEN8_RING_FAULT_REG);
-	} else if (INTEL_GEN(dev_priv) >= 6) {
+	if (INTEL_GEN(i915) >= 8) {
+		rmw_clear(uncore, GEN8_RING_FAULT_REG, RING_FAULT_VALID);
+		intel_uncore_posting_read(uncore, GEN8_RING_FAULT_REG);
+	} else if (INTEL_GEN(i915) >= 6) {
 		struct intel_engine_cs *engine;
 		enum intel_engine_id id;
 
-		for_each_engine(engine, dev_priv, id) {
-			I915_WRITE(RING_FAULT_REG(engine),
-				   I915_READ(RING_FAULT_REG(engine)) &
-				   ~RING_FAULT_VALID);
+		for_each_engine(engine, i915, id) {
+			rmw_clear(uncore,
+				  RING_FAULT_REG(engine), RING_FAULT_VALID);
+			intel_uncore_posting_read(uncore,
+						  RING_FAULT_REG(engine));
 		}
-		POSTING_READ(RING_FAULT_REG(dev_priv->engine[RCS]));
 	}
 }
 
@@ -1208,13 +1273,14 @@ void i915_clear_error_registers(struct drm_i915_private *dev_priv)
  * of a ring dump etc.).
  */
 void i915_handle_error(struct drm_i915_private *i915,
-		       u32 engine_mask,
+		       intel_engine_mask_t engine_mask,
 		       unsigned long flags,
 		       const char *fmt, ...)
 {
+	struct i915_gpu_error *error = &i915->gpu_error;
 	struct intel_engine_cs *engine;
 	intel_wakeref_t wakeref;
-	unsigned int tmp;
+	intel_engine_mask_t tmp;
 	char error_msg[80];
 	char *msg = NULL;
 
@@ -1237,7 +1303,7 @@ void i915_handle_error(struct drm_i915_private *i915,
 	 */
 	wakeref = intel_runtime_pm_get(i915);
 
-	engine_mask &= INTEL_INFO(i915)->ring_mask;
+	engine_mask &= INTEL_INFO(i915)->engine_mask;
 
 	if (flags & I915_ERROR_CAPTURE) {
 		i915_capture_error_state(i915, engine_mask, msg);
@@ -1248,20 +1314,19 @@ void i915_handle_error(struct drm_i915_private *i915,
 	 * Try engine reset when available. We fall back to full reset if
 	 * single reset fails.
 	 */
-	if (intel_has_reset_engine(i915) &&
-	    !i915_terminally_wedged(&i915->gpu_error)) {
+	if (intel_has_reset_engine(i915) && !__i915_wedged(error)) {
 		for_each_engine_masked(engine, i915, engine_mask, tmp) {
 			BUILD_BUG_ON(I915_RESET_MODESET >= I915_RESET_ENGINE);
 			if (test_and_set_bit(I915_RESET_ENGINE + engine->id,
-					     &i915->gpu_error.flags))
+					     &error->flags))
 				continue;
 
 			if (i915_reset_engine(engine, msg) == 0)
-				engine_mask &= ~intel_engine_flag(engine);
+				engine_mask &= ~engine->mask;
 
 			clear_bit(I915_RESET_ENGINE + engine->id,
-				  &i915->gpu_error.flags);
-			wake_up_bit(&i915->gpu_error.flags,
+				  &error->flags);
+			wake_up_bit(&error->flags,
 				    I915_RESET_ENGINE + engine->id);
 		}
 	}
@@ -1270,18 +1335,20 @@ void i915_handle_error(struct drm_i915_private *i915,
 		goto out;
 
 	/* Full reset needs the mutex, stop any other user trying to do so. */
-	if (test_and_set_bit(I915_RESET_BACKOFF, &i915->gpu_error.flags)) {
-		wait_event(i915->gpu_error.reset_queue,
-			   !test_bit(I915_RESET_BACKOFF,
-				     &i915->gpu_error.flags));
-		goto out;
+	if (test_and_set_bit(I915_RESET_BACKOFF, &error->flags)) {
+		wait_event(error->reset_queue,
+			   !test_bit(I915_RESET_BACKOFF, &error->flags));
+		goto out; /* piggy-back on the other reset */
 	}
 
+	/* Make sure i915_reset_trylock() sees the I915_RESET_BACKOFF */
+	synchronize_rcu_expedited();
+
 	/* Prevent any other reset-engine attempt. */
 	for_each_engine(engine, i915, tmp) {
 		while (test_and_set_bit(I915_RESET_ENGINE + engine->id,
-					&i915->gpu_error.flags))
-			wait_on_bit(&i915->gpu_error.flags,
+					&error->flags))
+			wait_on_bit(&error->flags,
 				    I915_RESET_ENGINE + engine->id,
 				    TASK_UNINTERRUPTIBLE);
 	}
@@ -1290,16 +1357,74 @@ void i915_handle_error(struct drm_i915_private *i915,
 
 	for_each_engine(engine, i915, tmp) {
 		clear_bit(I915_RESET_ENGINE + engine->id,
-			  &i915->gpu_error.flags);
+			  &error->flags);
 	}
 
-	clear_bit(I915_RESET_BACKOFF, &i915->gpu_error.flags);
-	wake_up_all(&i915->gpu_error.reset_queue);
+	clear_bit(I915_RESET_BACKOFF, &error->flags);
+	wake_up_all(&error->reset_queue);
 
 out:
 	intel_runtime_pm_put(i915, wakeref);
 }
 
+int i915_reset_trylock(struct drm_i915_private *i915)
+{
+	struct i915_gpu_error *error = &i915->gpu_error;
+	int srcu;
+
+	might_lock(&error->reset_backoff_srcu);
+	might_sleep();
+
+	rcu_read_lock();
+	while (test_bit(I915_RESET_BACKOFF, &error->flags)) {
+		rcu_read_unlock();
+
+		if (wait_event_interruptible(error->reset_queue,
+					     !test_bit(I915_RESET_BACKOFF,
+						       &error->flags)))
+			return -EINTR;
+
+		rcu_read_lock();
+	}
+	srcu = srcu_read_lock(&error->reset_backoff_srcu);
+	rcu_read_unlock();
+
+	return srcu;
+}
+
+void i915_reset_unlock(struct drm_i915_private *i915, int tag)
+__releases(&i915->gpu_error.reset_backoff_srcu)
+{
+	struct i915_gpu_error *error = &i915->gpu_error;
+
+	srcu_read_unlock(&error->reset_backoff_srcu, tag);
+}
+
+int i915_terminally_wedged(struct drm_i915_private *i915)
+{
+	struct i915_gpu_error *error = &i915->gpu_error;
+
+	might_sleep();
+
+	if (!__i915_wedged(error))
+		return 0;
+
+	/* Reset still in progress? Maybe we will recover? */
+	if (!test_bit(I915_RESET_BACKOFF, &error->flags))
+		return -EIO;
+
+	/* XXX intel_reset_finish() still takes struct_mutex!!! */
+	if (mutex_is_locked(&i915->drm.struct_mutex))
+		return -EAGAIN;
+
+	if (wait_event_interruptible(error->reset_queue,
+				     !test_bit(I915_RESET_BACKOFF,
+					       &error->flags)))
+		return -EINTR;
+
+	return __i915_wedged(error) ? -EIO : 0;
+}
+
 bool i915_reset_flush(struct drm_i915_private *i915)
 {
 	int err;