Merge tag 'drm-intel-gt-next-2021-08-06-1' of ssh://git.freedesktop.org/git/drm/drm-intel into drm-next

UAPI Changes:

- Add I915_MMAP_OFFSET_FIXED

  On devices with local memory `I915_MMAP_OFFSET_FIXED` is the only valid
  type. On devices without local memory, this caching mode is invalid.

  As caching mode when specifying `I915_MMAP_OFFSET_FIXED`, WC or WB will
  be used, depending on the object placement on creation. WB will be used
  when the object can only exist in system memory, WC otherwise.

  Userspace: https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/11888

- Reinstate the mmap ioctl for (already released) integrated Gen12 platforms

  Rationale: Otherwise media driver breaks eg. for ADL-P. Long term goal is
  still to sunset the IOCTL even for integrated and require using mmap_offset.

- Reject caching/set_domain IOCTLs on discrete

  Expected to become immutable property of the BO

- Disallow changing context parameters after first use on Gen12 and earlier
- Require setting context parameters at creation on platforms after Gen12

  Rationale (for both): Allow less dynamic changes to the context to simplify
  the implementation and avoid user shooting theirselves in the foot.

- Drop I915_CONTEXT_PARAM_RINGSIZE

  Userspace PR for compute-driver has not been merged

- Drop I915_CONTEXT_PARAM_NO_ZEROMAP

  Userspace PR for libdrm / Beignet was never landed

- Drop CONTEXT_CLONE API

  Userspace PR for Mesa was never landed

- Drop getparam support for I915_CONTEXT_PARAM_ENGINES

  Only existed for symmetry wrt. setparam, never used.

- Disallow bonding of virtual engines

  Drop the prep work, no hardware has been released needing it.

- (Implicit) Disable gpu relocations

  Media userspace was the last userspace to still use them. They
  have converted so performance can be regained with an update.

Core Changes:

- Merge topic branch 'topic/i915-ttm-2021-06-11' (from Maarten)
- Merge topic branch 'topic/revid_steppings' (from Matt R)
- Merge topic branch 'topic/xehp-dg2-definitions-2021-07-21' (from Matt R)
- Backmerges drm-next (Rodrigo)

Driver Changes:

- Initial workarounds for ADL-P (Clint)
- Preliminary code for XeHP/DG2 (Stuart, Umesh, Matt R, Prathap, Ram,
  Venkata, Akeem, Tvrtko, John, Lucas)
- Fix ADL-S DMA mask size to 39 bits (Tejas)
- Remove code for CNL (Lucas)
- Add ADL-P GuC/HuC firmwares (John)
- Update HuC to 7.9.3 for TGL/ADL-S/RKL (John)
- Fix -EDEADLK handling regression (Ville)
- Implement Wa_1508744258 for DG1 and Gen12 iGFX (Jose)
- Extend Wa_1406941453 to ADL-S (Jose)
- Drop unnecessary workarounds per stepping for SKL/BXT/ICL (Matt R)
- Use fuse info to enable SFC on Gen12 (Venkata)
- Unconditionally flush the pages on acquire on EHL/JSL (Matt A)
- Probe existence of backing struct pages upon userptr creation (Chris, Matt A)

- Add an intermediate GEM proto-context to delay real context creation (Jason)
- Implement SINGLE_TIMELINE with a syncobj (Jason)
- Set the watchdog timeout directly in intel_context_set_gem (Jason)
- Disallow userspace from creating contexts with too many engines (Jason)
- Revert "drm/i915/gem: Asynchronous cmdparser" (Jason)
- Revert "drm/i915: Propagate errors on awaiting already signaled fences" (Jason)
- Revert "drm/i915: Skip over MI_NOOP when parsing" (Jason)
- Revert "drm/i915: Shrink the GEM kmem_caches upon idling" (Daniel)
- Always let TTM handle object migration (Jason)
- Correct the locking and pin pattern for dma-buf (Thomas H, Michael R, Jason)
- Migrate to system at dma-buf attach time (Thomas, Michael R)

- MAJOR refactoring of the GuC backend code to allow for enabling on Gen11+
  (Matt B, John, Michal Wa., Fernando, Daniele, Vinay)
- Update GuC firmware interface to v62.0.0 (John, Michal Wa., Matt B)
- Add GuCRC feature to hand over the control of HW RC6 to the GuC on
  Gen12+ when GuC submission is enabled (Vinay, Sujaritha, Daniele,
  John, Tvrtko)
- Use the correct IRQ during resume and eliminate DRM IRQ midlayer (Thomas Z)
- Add pipelined page migration and clearing (Chris, Thomas H)
- Use TTM for system memory on discrete (Thomas H)
- Implement object migration for display vs. dma-buf (Thomas H)
- Perform execbuffer object locking as a separate step (Thomas H)
- Add support for explicit L3BANK steering (Matt, Daniele)
- Remove duplicated call to ops->pread (Daniel)
- Fix pagefault disabling in the first execbuf slowpath (Daniel)
- Simplify userptr locking (Thomas H)
- Improvements to the GuC CTB code (Matt B, John)
- Make GT workaround upper bounds exclusive (Matt R)
- Check for nomodeset in i915_init() first (Daniel)
- Delete now unused gpu reloc code (Daniel)

- Document RFC plans for GuC submission, DRM scheduler and new parallel
  submit uAPI (Matt B)
- Reintroduce buddy allocator this time with TTM (Matt A)
- Support forcing page size with LMEM (Matt A)
- Add i915_sched_engine to abstract a submission queue between backends (Matt B)
- Use accelerated move in TTM (Ram)
- Fix memory leaks from TTM backend (Thomas H)
- Introduce WW transaction helper (Thomas H)
- Improve debug Kconfig texts a bit (Daniel)
- Unify user object creation code (Jason)
- Use a table for i915_init/exit (Jason)
- Move slabs to module init/exit (Daniel)
- Remove now unused i915_globals (Daniel)
- Extract i915_module.c (Daniel)

- Consistently use adl-p/adl-s in WA comments (Jose)
- Finish INTEL_GEN and friends conversion (Lucas)
- Correct variable/function namings (Lucas)
- Code checker fixes (Wan, Matt A)
- Tracepoint improvements (Matt B)
- Kerneldoc improvements (Tvrtko, Jason, Matt A, Maarten)
- Selftest improvements (Chris, Matt A, Tejas, Thomas H, John, Matt B,
  Rahul, Vinay)

Signed-off-by: Dave Airlie <airlied@redhat.com>

From: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/YQ0JmYiXhGskNcrI@jlahtine-mobl.ger.corp.intel.com

1 files changed, 475 insertions, 228 deletions

diff --git a/drivers/gpu/drm/i915/gt/uc/intel_guc_ct.c b/drivers/gpu/drm/i915/gt/uc/intel_guc_ct.c
index 8f7b148fef58..22b4733b55e2 100644
--- a/drivers/gpu/drm/i915/gt/uc/intel_guc_ct.c
+++ b/drivers/gpu/drm/i915/gt/uc/intel_guc_ct.c
@@ -3,6 +3,11 @@
  * Copyright © 2016-2019 Intel Corporation
  */
 
+#include <linux/circ_buf.h>
+#include <linux/ktime.h>
+#include <linux/time64.h>
+#include <linux/timekeeping.h>
+
 #include "i915_drv.h"
 #include "intel_guc_ct.h"
 #include "gt/intel_gt.h"
@@ -58,11 +63,17 @@ static inline struct drm_device *ct_to_drm(struct intel_guc_ct *ct)
  *      +--------+-----------------------------------------------+------+
  *
  * Size of each `CT Buffer`_ must be multiple of 4K.
- * As we don't expect too many messages, for now use minimum sizes.
+ * We don't expect too many messages in flight at any time, unless we are
+ * using the GuC submission. In that case each request requires a minimum
+ * 2 dwords which gives us a maximum 256 queue'd requests. Hopefully this
+ * enough space to avoid backpressure on the driver. We increase the size
+ * of the receive buffer (relative to the send) to ensure a G2H response
+ * CTB has a landing spot.
  */
 #define CTB_DESC_SIZE		ALIGN(sizeof(struct guc_ct_buffer_desc), SZ_2K)
 #define CTB_H2G_BUFFER_SIZE	(SZ_4K)
-#define CTB_G2H_BUFFER_SIZE	(SZ_4K)
+#define CTB_G2H_BUFFER_SIZE	(4 * CTB_H2G_BUFFER_SIZE)
+#define G2H_ROOM_BUFFER_SIZE	(CTB_G2H_BUFFER_SIZE / 4)
 
 struct ct_request {
 	struct list_head link;
@@ -98,66 +109,84 @@ void intel_guc_ct_init_early(struct intel_guc_ct *ct)
 	INIT_LIST_HEAD(&ct->requests.incoming);
 	INIT_WORK(&ct->requests.worker, ct_incoming_request_worker_func);
 	tasklet_setup(&ct->receive_tasklet, ct_receive_tasklet_func);
+	init_waitqueue_head(&ct->wq);
 }
 
 static inline const char *guc_ct_buffer_type_to_str(u32 type)
 {
 	switch (type) {
-	case INTEL_GUC_CT_BUFFER_TYPE_SEND:
+	case GUC_CTB_TYPE_HOST2GUC:
 		return "SEND";
-	case INTEL_GUC_CT_BUFFER_TYPE_RECV:
+	case GUC_CTB_TYPE_GUC2HOST:
 		return "RECV";
 	default:
 		return "<invalid>";
 	}
 }
 
-static void guc_ct_buffer_desc_init(struct guc_ct_buffer_desc *desc,
-				    u32 cmds_addr, u32 size)
+static void guc_ct_buffer_desc_init(struct guc_ct_buffer_desc *desc)
 {
 	memset(desc, 0, sizeof(*desc));
-	desc->addr = cmds_addr;
-	desc->size = size;
-	desc->owner = CTB_OWNER_HOST;
 }
 
-static void guc_ct_buffer_reset(struct intel_guc_ct_buffer *ctb, u32 cmds_addr)
+static void guc_ct_buffer_reset(struct intel_guc_ct_buffer *ctb)
 {
-	guc_ct_buffer_desc_init(ctb->desc, cmds_addr, ctb->size);
+	u32 space;
+
+	ctb->broken = false;
+	ctb->tail = 0;
+	ctb->head = 0;
+	space = CIRC_SPACE(ctb->tail, ctb->head, ctb->size) - ctb->resv_space;
+	atomic_set(&ctb->space, space);
+
+	guc_ct_buffer_desc_init(ctb->desc);
 }
 
 static void guc_ct_buffer_init(struct intel_guc_ct_buffer *ctb,
 			       struct guc_ct_buffer_desc *desc,
-			       u32 *cmds, u32 size)
+			       u32 *cmds, u32 size_in_bytes, u32 resv_space)
 {
-	GEM_BUG_ON(size % 4);
+	GEM_BUG_ON(size_in_bytes % 4);
 
 	ctb->desc = desc;
 	ctb->cmds = cmds;
-	ctb->size = size;
+	ctb->size = size_in_bytes / 4;
+	ctb->resv_space = resv_space / 4;
 
-	guc_ct_buffer_reset(ctb, 0);
+	guc_ct_buffer_reset(ctb);
 }
 
-static int guc_action_register_ct_buffer(struct intel_guc *guc,
-					 u32 desc_addr,
-					 u32 type)
+static int guc_action_register_ct_buffer(struct intel_guc *guc, u32 type,
+					 u32 desc_addr, u32 buff_addr, u32 size)
 {
-	u32 action[] = {
-		INTEL_GUC_ACTION_REGISTER_COMMAND_TRANSPORT_BUFFER,
-		desc_addr,
-		sizeof(struct guc_ct_buffer_desc),
-		type
+	u32 request[HOST2GUC_REGISTER_CTB_REQUEST_MSG_LEN] = {
+		FIELD_PREP(GUC_HXG_MSG_0_ORIGIN, GUC_HXG_ORIGIN_HOST) |
+		FIELD_PREP(GUC_HXG_MSG_0_TYPE, GUC_HXG_TYPE_REQUEST) |
+		FIELD_PREP(GUC_HXG_REQUEST_MSG_0_ACTION, GUC_ACTION_HOST2GUC_REGISTER_CTB),
+		FIELD_PREP(HOST2GUC_REGISTER_CTB_REQUEST_MSG_1_SIZE, size / SZ_4K - 1) |
+		FIELD_PREP(HOST2GUC_REGISTER_CTB_REQUEST_MSG_1_TYPE, type),
+		FIELD_PREP(HOST2GUC_REGISTER_CTB_REQUEST_MSG_2_DESC_ADDR, desc_addr),
+		FIELD_PREP(HOST2GUC_REGISTER_CTB_REQUEST_MSG_3_BUFF_ADDR, buff_addr),
 	};
 
-	/* Can't use generic send(), CT registration must go over MMIO */
-	return intel_guc_send_mmio(guc, action, ARRAY_SIZE(action), NULL, 0);
+	GEM_BUG_ON(type != GUC_CTB_TYPE_HOST2GUC && type != GUC_CTB_TYPE_GUC2HOST);
+	GEM_BUG_ON(size % SZ_4K);
+
+	/* CT registration must go over MMIO */
+	return intel_guc_send_mmio(guc, request, ARRAY_SIZE(request), NULL, 0);
 }
 
-static int ct_register_buffer(struct intel_guc_ct *ct, u32 desc_addr, u32 type)
+static int ct_register_buffer(struct intel_guc_ct *ct, u32 type,
+			      u32 desc_addr, u32 buff_addr, u32 size)
 {
-	int err = guc_action_register_ct_buffer(ct_to_guc(ct), desc_addr, type);
+	int err;
+
+	err = i915_inject_probe_error(guc_to_gt(ct_to_guc(ct))->i915, -ENXIO);
+	if (unlikely(err))
+		return err;
 
+	err = guc_action_register_ct_buffer(ct_to_guc(ct), type,
+					    desc_addr, buff_addr, size);
 	if (unlikely(err))
 		CT_ERROR(ct, "Failed to register %s buffer (err=%d)\n",
 			 guc_ct_buffer_type_to_str(type), err);
@@ -166,14 +195,17 @@ static int ct_register_buffer(struct intel_guc_ct *ct, u32 desc_addr, u32 type)
 
 static int guc_action_deregister_ct_buffer(struct intel_guc *guc, u32 type)
 {
-	u32 action[] = {
-		INTEL_GUC_ACTION_DEREGISTER_COMMAND_TRANSPORT_BUFFER,
-		CTB_OWNER_HOST,
-		type
+	u32 request[HOST2GUC_DEREGISTER_CTB_REQUEST_MSG_LEN] = {
+		FIELD_PREP(GUC_HXG_MSG_0_ORIGIN, GUC_HXG_ORIGIN_HOST) |
+		FIELD_PREP(GUC_HXG_MSG_0_TYPE, GUC_HXG_TYPE_REQUEST) |
+		FIELD_PREP(GUC_HXG_REQUEST_MSG_0_ACTION, GUC_ACTION_HOST2GUC_DEREGISTER_CTB),
+		FIELD_PREP(HOST2GUC_DEREGISTER_CTB_REQUEST_MSG_1_TYPE, type),
 	};
 
-	/* Can't use generic send(), CT deregistration must go over MMIO */
-	return intel_guc_send_mmio(guc, action, ARRAY_SIZE(action), NULL, 0);
+	GEM_BUG_ON(type != GUC_CTB_TYPE_HOST2GUC && type != GUC_CTB_TYPE_GUC2HOST);
+
+	/* CT deregistration must go over MMIO */
+	return intel_guc_send_mmio(guc, request, ARRAY_SIZE(request), NULL, 0);
 }
 
 static int ct_deregister_buffer(struct intel_guc_ct *ct, u32 type)
@@ -200,10 +232,15 @@ int intel_guc_ct_init(struct intel_guc_ct *ct)
 	struct guc_ct_buffer_desc *desc;
 	u32 blob_size;
 	u32 cmds_size;
+	u32 resv_space;
 	void *blob;
 	u32 *cmds;
 	int err;
 
+	err = i915_inject_probe_error(guc_to_gt(guc)->i915, -ENXIO);
+	if (err)
+		return err;
+
 	GEM_BUG_ON(ct->vma);
 
 	blob_size = 2 * CTB_DESC_SIZE + CTB_H2G_BUFFER_SIZE + CTB_G2H_BUFFER_SIZE;
@@ -220,19 +257,23 @@ int intel_guc_ct_init(struct intel_guc_ct *ct)
 	desc = blob;
 	cmds = blob + 2 * CTB_DESC_SIZE;
 	cmds_size = CTB_H2G_BUFFER_SIZE;
-	CT_DEBUG(ct, "%s desc %#tx cmds %#tx size %u\n", "send",
-		 ptrdiff(desc, blob), ptrdiff(cmds, blob), cmds_size);
+	resv_space = 0;
+	CT_DEBUG(ct, "%s desc %#tx cmds %#tx size %u/%u\n", "send",
+		 ptrdiff(desc, blob), ptrdiff(cmds, blob), cmds_size,
+		 resv_space);
 
-	guc_ct_buffer_init(&ct->ctbs.send, desc, cmds, cmds_size);
+	guc_ct_buffer_init(&ct->ctbs.send, desc, cmds, cmds_size, resv_space);
 
 	/* store pointers to desc and cmds for recv ctb */
 	desc = blob + CTB_DESC_SIZE;
 	cmds = blob + 2 * CTB_DESC_SIZE + CTB_H2G_BUFFER_SIZE;
 	cmds_size = CTB_G2H_BUFFER_SIZE;
-	CT_DEBUG(ct, "%s desc %#tx cmds %#tx size %u\n", "recv",
-		 ptrdiff(desc, blob), ptrdiff(cmds, blob), cmds_size);
+	resv_space = G2H_ROOM_BUFFER_SIZE;
+	CT_DEBUG(ct, "%s desc %#tx cmds %#tx size %u/%u\n", "recv",
+		 ptrdiff(desc, blob), ptrdiff(cmds, blob), cmds_size,
+		 resv_space);
 
-	guc_ct_buffer_init(&ct->ctbs.recv, desc, cmds, cmds_size);
+	guc_ct_buffer_init(&ct->ctbs.recv, desc, cmds, cmds_size, resv_space);
 
 	return 0;
 }
@@ -261,7 +302,7 @@ void intel_guc_ct_fini(struct intel_guc_ct *ct)
 int intel_guc_ct_enable(struct intel_guc_ct *ct)
 {
 	struct intel_guc *guc = ct_to_guc(ct);
-	u32 base, cmds;
+	u32 base, desc, cmds;
 	void *blob;
 	int err;
 
@@ -277,32 +318,36 @@ int intel_guc_ct_enable(struct intel_guc_ct *ct)
 	GEM_BUG_ON(blob != ct->ctbs.send.desc);
 
 	/* (re)initialize descriptors */
-	cmds = base + ptrdiff(ct->ctbs.send.cmds, blob);
-	guc_ct_buffer_reset(&ct->ctbs.send, cmds);
-
-	cmds = base + ptrdiff(ct->ctbs.recv.cmds, blob);
-	guc_ct_buffer_reset(&ct->ctbs.recv, cmds);
+	guc_ct_buffer_reset(&ct->ctbs.send);
+	guc_ct_buffer_reset(&ct->ctbs.recv);
 
 	/*
 	 * Register both CT buffers starting with RECV buffer.
 	 * Descriptors are in first half of the blob.
 	 */
-	err = ct_register_buffer(ct, base + ptrdiff(ct->ctbs.recv.desc, blob),
-				 INTEL_GUC_CT_BUFFER_TYPE_RECV);
+	desc = base + ptrdiff(ct->ctbs.recv.desc, blob);
+	cmds = base + ptrdiff(ct->ctbs.recv.cmds, blob);
+	err = ct_register_buffer(ct, GUC_CTB_TYPE_GUC2HOST,
+				 desc, cmds, ct->ctbs.recv.size * 4);
+
 	if (unlikely(err))
 		goto err_out;
 
-	err = ct_register_buffer(ct, base + ptrdiff(ct->ctbs.send.desc, blob),
-				 INTEL_GUC_CT_BUFFER_TYPE_SEND);
+	desc = base + ptrdiff(ct->ctbs.send.desc, blob);
+	cmds = base + ptrdiff(ct->ctbs.send.cmds, blob);
+	err = ct_register_buffer(ct, GUC_CTB_TYPE_HOST2GUC,
+				 desc, cmds, ct->ctbs.send.size * 4);
+
 	if (unlikely(err))
 		goto err_deregister;
 
 	ct->enabled = true;
+	ct->stall_time = KTIME_MAX;
 
 	return 0;
 
 err_deregister:
-	ct_deregister_buffer(ct, INTEL_GUC_CT_BUFFER_TYPE_RECV);
+	ct_deregister_buffer(ct, GUC_CTB_TYPE_GUC2HOST);
 err_out:
 	CT_PROBE_ERROR(ct, "Failed to enable CTB (%pe)\n", ERR_PTR(err));
 	return err;
@@ -321,8 +366,8 @@ void intel_guc_ct_disable(struct intel_guc_ct *ct)
 	ct->enabled = false;
 
 	if (intel_guc_is_fw_running(guc)) {
-		ct_deregister_buffer(ct, INTEL_GUC_CT_BUFFER_TYPE_SEND);
-		ct_deregister_buffer(ct, INTEL_GUC_CT_BUFFER_TYPE_RECV);
+		ct_deregister_buffer(ct, GUC_CTB_TYPE_HOST2GUC);
+		ct_deregister_buffer(ct, GUC_CTB_TYPE_GUC2HOST);
 	}
 }
 
@@ -354,81 +399,63 @@ static void write_barrier(struct intel_guc_ct *ct)
 	}
 }
 
-/**
- * DOC: CTB Host to GuC request
- *
- * Format of the CTB Host to GuC request message is as follows::
- *
- *      +------------+---------+---------+---------+---------+
- *      |   msg[0]   |   [1]   |   [2]   |   ...   |  [n-1]  |
- *      +------------+---------+---------+---------+---------+
- *      |   MESSAGE  |       MESSAGE PAYLOAD                 |
- *      +   HEADER   +---------+---------+---------+---------+
- *      |            |    0    |    1    |   ...   |    n    |
- *      +============+=========+=========+=========+=========+
- *      |  len >= 1  |  FENCE  |     request specific data   |
- *      +------+-----+---------+---------+---------+---------+
- *
- *                   ^-----------------len-------------------^
- */
-
 static int ct_write(struct intel_guc_ct *ct,
 		    const u32 *action,
 		    u32 len /* in dwords */,
-		    u32 fence)
+		    u32 fence, u32 flags)
 {
 	struct intel_guc_ct_buffer *ctb = &ct->ctbs.send;
 	struct guc_ct_buffer_desc *desc = ctb->desc;
-	u32 head = desc->head;
-	u32 tail = desc->tail;
+	u32 tail = ctb->tail;
 	u32 size = ctb->size;
-	u32 used;
 	u32 header;
+	u32 hxg;
+	u32 type;
 	u32 *cmds = ctb->cmds;
 	unsigned int i;
 
-	if (unlikely(desc->is_in_error))
-		return -EPIPE;
-
-	if (unlikely(!IS_ALIGNED(head | tail, 4) ||
-		     (tail | head) >= size))
+	if (unlikely(desc->status))
 		goto corrupted;
 
-	/* later calculations will be done in dwords */
-	head /= 4;
-	tail /= 4;
-	size /= 4;
-
-	/*
-	 * tail == head condition indicates empty. GuC FW does not support
-	 * using up the entire buffer to get tail == head meaning full.
-	 */
-	if (tail < head)
-		used = (size - head) + tail;
-	else
-		used = tail - head;
+	GEM_BUG_ON(tail > size);
 
-	/* make sure there is a space including extra dw for the fence */
-	if (unlikely(used + len + 1 >= size))
-		return -ENOSPC;
+#ifdef CONFIG_DRM_I915_DEBUG_GUC
+	if (unlikely(tail != READ_ONCE(desc->tail))) {
+		CT_ERROR(ct, "Tail was modified %u != %u\n",
+			 desc->tail, tail);
+		desc->status |= GUC_CTB_STATUS_MISMATCH;
+		goto corrupted;
+	}
+	if (unlikely(READ_ONCE(desc->head) >= size)) {
+		CT_ERROR(ct, "Invalid head offset %u >= %u)\n",
+			 desc->head, size);
+		desc->status |= GUC_CTB_STATUS_OVERFLOW;
+		goto corrupted;
+	}
+#endif
 
 	/*
-	 * Write the message. The format is the following:
-	 * DW0: header (including action code)
-	 * DW1: fence
-	 * DW2+: action data
+	 * dw0: CT header (including fence)
+	 * dw1: HXG header (including action code)
+	 * dw2+: action data
 	 */
-	header = (len << GUC_CT_MSG_LEN_SHIFT) |
-		 GUC_CT_MSG_SEND_STATUS |
-		 (action[0] << GUC_CT_MSG_ACTION_SHIFT);
+	header = FIELD_PREP(GUC_CTB_MSG_0_FORMAT, GUC_CTB_FORMAT_HXG) |
+		 FIELD_PREP(GUC_CTB_MSG_0_NUM_DWORDS, len) |
+		 FIELD_PREP(GUC_CTB_MSG_0_FENCE, fence);
 
-	CT_DEBUG(ct, "writing %*ph %*ph %*ph\n",
-		 4, &header, 4, &fence, 4 * (len - 1), &action[1]);
+	type = (flags & INTEL_GUC_CT_SEND_NB) ? GUC_HXG_TYPE_EVENT :
+		GUC_HXG_TYPE_REQUEST;
+	hxg = FIELD_PREP(GUC_HXG_MSG_0_TYPE, type) |
+		FIELD_PREP(GUC_HXG_EVENT_MSG_0_ACTION |
+			   GUC_HXG_EVENT_MSG_0_DATA0, action[0]);
+
+	CT_DEBUG(ct, "writing (tail %u) %*ph %*ph %*ph\n",
+		 tail, 4, &header, 4, &hxg, 4 * (len - 1), &action[1]);
 
 	cmds[tail] = header;
 	tail = (tail + 1) % size;
 
-	cmds[tail] = fence;
+	cmds[tail] = hxg;
 	tail = (tail + 1) % size;
 
 	for (i = 1; i < len; i++) {
@@ -443,14 +470,20 @@ static int ct_write(struct intel_guc_ct *ct,
 	 */
 	write_barrier(ct);
 
-	/* now update desc tail (back in bytes) */
-	desc->tail = tail * 4;
+	/* update local copies */
+	ctb->tail = tail;
+	GEM_BUG_ON(atomic_read(&ctb->space) < len + GUC_CTB_HDR_LEN);
+	atomic_sub(len + GUC_CTB_HDR_LEN, &ctb->space);
+
+	/* now update descriptor */
+	WRITE_ONCE(desc->tail, tail);
+
 	return 0;
 
 corrupted:
-	CT_ERROR(ct, "Corrupted descriptor addr=%#x head=%u tail=%u size=%u\n",
-		 desc->addr, desc->head, desc->tail, desc->size);
-	desc->is_in_error = 1;
+	CT_ERROR(ct, "Corrupted descriptor head=%u tail=%u status=%#x\n",
+		 desc->head, desc->tail, desc->status);
+	ctb->broken = true;
 	return -EPIPE;
 }
 
@@ -459,7 +492,7 @@ corrupted:
  * @req:	pointer to pending request
  * @status:	placeholder for status
  *
- * For each sent request, Guc shall send bac CT response message.
+ * For each sent request, GuC shall send back CT response message.
  * Our message handler will update status of tracked request once
  * response message with given fence is received. Wait here and
  * check for valid response status value.
@@ -475,12 +508,18 @@ static int wait_for_ct_request_update(struct ct_request *req, u32 *status)
 	/*
 	 * Fast commands should complete in less than 10us, so sample quickly
 	 * up to that length of time, then switch to a slower sleep-wait loop.
-	 * No GuC command should ever take longer than 10ms.
+	 * No GuC command should ever take longer than 10ms but many GuC
+	 * commands can be inflight at time, so use a 1s timeout on the slower
+	 * sleep-wait loop.
 	 */
-#define done INTEL_GUC_MSG_IS_RESPONSE(READ_ONCE(req->status))
-	err = wait_for_us(done, 10);
+#define GUC_CTB_RESPONSE_TIMEOUT_SHORT_MS 10
+#define GUC_CTB_RESPONSE_TIMEOUT_LONG_MS 1000
+#define done \
+	(FIELD_GET(GUC_HXG_MSG_0_ORIGIN, READ_ONCE(req->status)) == \
+	 GUC_HXG_ORIGIN_GUC)
+	err = wait_for_us(done, GUC_CTB_RESPONSE_TIMEOUT_SHORT_MS);
 	if (err)
-		err = wait_for(done, 10);
+		err = wait_for(done, GUC_CTB_RESPONSE_TIMEOUT_LONG_MS);
 #undef done
 
 	if (unlikely(err))
@@ -490,6 +529,131 @@ static int wait_for_ct_request_update(struct ct_request *req, u32 *status)
 	return err;
 }
 
+#define GUC_CTB_TIMEOUT_MS	1500
+static inline bool ct_deadlocked(struct intel_guc_ct *ct)
+{
+	long timeout = GUC_CTB_TIMEOUT_MS;
+	bool ret = ktime_ms_delta(ktime_get(), ct->stall_time) > timeout;
+
+	if (unlikely(ret)) {
+		struct guc_ct_buffer_desc *send = ct->ctbs.send.desc;
+		struct guc_ct_buffer_desc *recv = ct->ctbs.send.desc;
+
+		CT_ERROR(ct, "Communication stalled for %lld ms, desc status=%#x,%#x\n",
+			 ktime_ms_delta(ktime_get(), ct->stall_time),
+			 send->status, recv->status);
+		ct->ctbs.send.broken = true;
+	}
+
+	return ret;
+}
+
+static inline bool g2h_has_room(struct intel_guc_ct *ct, u32 g2h_len_dw)
+{
+	struct intel_guc_ct_buffer *ctb = &ct->ctbs.recv;
+
+	/*
+	 * We leave a certain amount of space in the G2H CTB buffer for
+	 * unexpected G2H CTBs (e.g. logging, engine hang, etc...)
+	 */
+	return !g2h_len_dw || atomic_read(&ctb->space) >= g2h_len_dw;
+}
+
+static inline void g2h_reserve_space(struct intel_guc_ct *ct, u32 g2h_len_dw)
+{
+	lockdep_assert_held(&ct->ctbs.send.lock);
+
+	GEM_BUG_ON(!g2h_has_room(ct, g2h_len_dw));
+
+	if (g2h_len_dw)
+		atomic_sub(g2h_len_dw, &ct->ctbs.recv.space);
+}
+
+static inline void g2h_release_space(struct intel_guc_ct *ct, u32 g2h_len_dw)
+{
+	atomic_add(g2h_len_dw, &ct->ctbs.recv.space);
+}
+
+static inline bool h2g_has_room(struct intel_guc_ct *ct, u32 len_dw)
+{
+	struct intel_guc_ct_buffer *ctb = &ct->ctbs.send;
+	struct guc_ct_buffer_desc *desc = ctb->desc;
+	u32 head;
+	u32 space;
+
+	if (atomic_read(&ctb->space) >= len_dw)
+		return true;
+
+	head = READ_ONCE(desc->head);
+	if (unlikely(head > ctb->size)) {
+		CT_ERROR(ct, "Invalid head offset %u >= %u)\n",
+			 head, ctb->size);
+		desc->status |= GUC_CTB_STATUS_OVERFLOW;
+		ctb->broken = true;
+		return false;
+	}
+
+	space = CIRC_SPACE(ctb->tail, head, ctb->size);
+	atomic_set(&ctb->space, space);
+
+	return space >= len_dw;
+}
+
+static int has_room_nb(struct intel_guc_ct *ct, u32 h2g_dw, u32 g2h_dw)
+{
+	lockdep_assert_held(&ct->ctbs.send.lock);
+
+	if (unlikely(!h2g_has_room(ct, h2g_dw) || !g2h_has_room(ct, g2h_dw))) {
+		if (ct->stall_time == KTIME_MAX)
+			ct->stall_time = ktime_get();
+
+		if (unlikely(ct_deadlocked(ct)))
+			return -EPIPE;
+		else
+			return -EBUSY;
+	}
+
+	ct->stall_time = KTIME_MAX;
+	return 0;
+}
+
+#define G2H_LEN_DW(f) ({ \
+	typeof(f) f_ = (f); \
+	FIELD_GET(INTEL_GUC_CT_SEND_G2H_DW_MASK, f_) ? \
+	FIELD_GET(INTEL_GUC_CT_SEND_G2H_DW_MASK, f_) + \
+	GUC_CTB_HXG_MSG_MIN_LEN : 0; \
+})
+static int ct_send_nb(struct intel_guc_ct *ct,
+		      const u32 *action,
+		      u32 len,
+		      u32 flags)
+{
+	struct intel_guc_ct_buffer *ctb = &ct->ctbs.send;
+	unsigned long spin_flags;
+	u32 g2h_len_dw = G2H_LEN_DW(flags);
+	u32 fence;
+	int ret;
+
+	spin_lock_irqsave(&ctb->lock, spin_flags);
+
+	ret = has_room_nb(ct, len + GUC_CTB_HDR_LEN, g2h_len_dw);
+	if (unlikely(ret))
+		goto out;
+
+	fence = ct_get_next_fence(ct);
+	ret = ct_write(ct, action, len, fence, flags);
+	if (unlikely(ret))
+		goto out;
+
+	g2h_reserve_space(ct, g2h_len_dw);
+	intel_guc_notify(ct_to_guc(ct));
+
+out:
+	spin_unlock_irqrestore(&ctb->lock, spin_flags);
+
+	return ret;
+}
+
 static int ct_send(struct intel_guc_ct *ct,
 		   const u32 *action,
 		   u32 len,
@@ -497,8 +661,10 @@ static int ct_send(struct intel_guc_ct *ct,
 		   u32 response_buf_size,
 		   u32 *status)
 {
+	struct intel_guc_ct_buffer *ctb = &ct->ctbs.send;
 	struct ct_request request;
 	unsigned long flags;
+	unsigned int sleep_period_ms = 1;
 	u32 fence;
 	int err;
 
@@ -506,8 +672,33 @@ static int ct_send(struct intel_guc_ct *ct,
 	GEM_BUG_ON(!len);
 	GEM_BUG_ON(len & ~GUC_CT_MSG_LEN_MASK);
 	GEM_BUG_ON(!response_buf && response_buf_size);
+	might_sleep();
+
+	/*
+	 * We use a lazy spin wait loop here as we believe that if the CT
+	 * buffers are sized correctly the flow control condition should be
+	 * rare. Reserving the maximum size in the G2H credits as we don't know
+	 * how big the response is going to be.
+	 */
+retry:
+	spin_lock_irqsave(&ctb->lock, flags);
+	if (unlikely(!h2g_has_room(ct, len + GUC_CTB_HDR_LEN) ||
+		     !g2h_has_room(ct, GUC_CTB_HXG_MSG_MAX_LEN))) {
+		if (ct->stall_time == KTIME_MAX)
+			ct->stall_time = ktime_get();
+		spin_unlock_irqrestore(&ctb->lock, flags);
+
+		if (unlikely(ct_deadlocked(ct)))
+			return -EPIPE;
+
+		if (msleep_interruptible(sleep_period_ms))
+			return -EINTR;
+		sleep_period_ms = sleep_period_ms << 1;
+
+		goto retry;
+	}
 
-	spin_lock_irqsave(&ct->ctbs.send.lock, flags);
+	ct->stall_time = KTIME_MAX;
 
 	fence = ct_get_next_fence(ct);
 	request.fence = fence;
@@ -519,9 +710,10 @@ static int ct_send(struct intel_guc_ct *ct,
 	list_add_tail(&request.link, &ct->requests.pending);
 	spin_unlock(&ct->requests.lock);
 
-	err = ct_write(ct, action, len, fence);
+	err = ct_write(ct, action, len, fence, 0);
+	g2h_reserve_space(ct, GUC_CTB_HXG_MSG_MAX_LEN);
 
-	spin_unlock_irqrestore(&ct->ctbs.send.lock, flags);
+	spin_unlock_irqrestore(&ctb->lock, flags);
 
 	if (unlikely(err))
 		goto unlink;
@@ -529,24 +721,25 @@ static int ct_send(struct intel_guc_ct *ct,
 	intel_guc_notify(ct_to_guc(ct));
 
 	err = wait_for_ct_request_update(&request, status);
+	g2h_release_space(ct, GUC_CTB_HXG_MSG_MAX_LEN);
 	if (unlikely(err))
 		goto unlink;
 
-	if (!INTEL_GUC_MSG_IS_RESPONSE_SUCCESS(*status)) {
+	if (FIELD_GET(GUC_HXG_MSG_0_TYPE, *status) != GUC_HXG_TYPE_RESPONSE_SUCCESS) {
 		err = -EIO;
 		goto unlink;
 	}
 
 	if (response_buf) {
 		/* There shall be no data in the status */
-		WARN_ON(INTEL_GUC_MSG_TO_DATA(request.status));
+		WARN_ON(FIELD_GET(GUC_HXG_RESPONSE_MSG_0_DATA0, request.status));
 		/* Return actual response len */
 		err = request.response_len;
 	} else {
 		/* There shall be no response payload */
 		WARN_ON(request.response_len);
 		/* Return data decoded from the status dword */
-		err = INTEL_GUC_MSG_TO_DATA(*status);
+		err = FIELD_GET(GUC_HXG_RESPONSE_MSG_0_DATA0, *status);
 	}
 
 unlink:
@@ -561,16 +754,25 @@ unlink:
  * Command Transport (CT) buffer based GuC send function.
  */
 int intel_guc_ct_send(struct intel_guc_ct *ct, const u32 *action, u32 len,
-		      u32 *response_buf, u32 response_buf_size)
+		      u32 *response_buf, u32 response_buf_size, u32 flags)
 {
 	u32 status = ~0; /* undefined */
 	int ret;
 
 	if (unlikely(!ct->enabled)) {
-		WARN(1, "Unexpected send: action=%#x\n", *action);
+		struct intel_guc *guc = ct_to_guc(ct);
+		struct intel_uc *uc = container_of(guc, struct intel_uc, guc);
+
+		WARN(!uc->reset_in_progress, "Unexpected send: action=%#x\n", *action);
 		return -ENODEV;
 	}
 
+	if (unlikely(ct->ctbs.send.broken))
+		return -EPIPE;
+
+	if (flags & INTEL_GUC_CT_SEND_NB)
+		return ct_send_nb(ct, action, len, flags);
+
 	ret = ct_send(ct, action, len, response_buf, response_buf_size, &status);
 	if (unlikely(ret < 0)) {
 		CT_ERROR(ct, "Sending action %#x failed (err=%d status=%#X)\n",
@@ -583,21 +785,6 @@ int intel_guc_ct_send(struct intel_guc_ct *ct, const u32 *action, u32 len,
 	return ret;
 }
 
-static inline unsigned int ct_header_get_len(u32 header)
-{
-	return (header >> GUC_CT_MSG_LEN_SHIFT) & GUC_CT_MSG_LEN_MASK;
-}
-
-static inline unsigned int ct_header_get_action(u32 header)
-{
-	return (header >> GUC_CT_MSG_ACTION_SHIFT) & GUC_CT_MSG_ACTION_MASK;
-}
-
-static inline bool ct_header_is_response(u32 header)
-{
-	return !!(header & GUC_CT_MSG_IS_RESPONSE);
-}
-
 static struct ct_incoming_msg *ct_alloc_msg(u32 num_dwords)
 {
 	struct ct_incoming_msg *msg;
@@ -621,8 +808,8 @@ static int ct_read(struct intel_guc_ct *ct, struct ct_incoming_msg **msg)
 {
 	struct intel_guc_ct_buffer *ctb = &ct->ctbs.recv;
 	struct guc_ct_buffer_desc *desc = ctb->desc;
-	u32 head = desc->head;
-	u32 tail = desc->tail;
+	u32 head = ctb->head;
+	u32 tail = READ_ONCE(desc->tail);
 	u32 size = ctb->size;
 	u32 *cmds = ctb->cmds;
 	s32 available;
@@ -630,17 +817,28 @@ static int ct_read(struct intel_guc_ct *ct, struct ct_incoming_msg **msg)
 	unsigned int i;
 	u32 header;
 
-	if (unlikely(desc->is_in_error))
+	if (unlikely(ctb->broken))
 		return -EPIPE;
 
-	if (unlikely(!IS_ALIGNED(head | tail, 4) ||
-		     (tail | head) >= size))
+	if (unlikely(desc->status))
 		goto corrupted;
 
-	/* later calculations will be done in dwords */
-	head /= 4;
-	tail /= 4;
-	size /= 4;
+	GEM_BUG_ON(head > size);
+
+#ifdef CONFIG_DRM_I915_DEBUG_GUC
+	if (unlikely(head != READ_ONCE(desc->head))) {
+		CT_ERROR(ct, "Head was modified %u != %u\n",
+			 desc->head, head);
+		desc->status |= GUC_CTB_STATUS_MISMATCH;
+		goto corrupted;
+	}
+#endif
+	if (unlikely(tail >= size)) {
+		CT_ERROR(ct, "Invalid tail offset %u >= %u)\n",
+			 tail, size);
+		desc->status |= GUC_CTB_STATUS_OVERFLOW;
+		goto corrupted;
+	}
 
 	/* tail == head condition indicates empty */
 	available = tail - head;
@@ -652,14 +850,14 @@ static int ct_read(struct intel_guc_ct *ct, struct ct_incoming_msg **msg)
 	/* beware of buffer wrap case */
 	if (unlikely(available < 0))
 		available += size;
-	CT_DEBUG(ct, "available %d (%u:%u)\n", available, head, tail);
+	CT_DEBUG(ct, "available %d (%u:%u:%u)\n", available, head, tail, size);
 	GEM_BUG_ON(available < 0);
 
 	header = cmds[head];
 	head = (head + 1) % size;
 
 	/* message len with header */
-	len = ct_header_get_len(header) + 1;
+	len = FIELD_GET(GUC_CTB_MSG_0_NUM_DWORDS, header) + GUC_CTB_MSG_MIN_LEN;
 	if (unlikely(len > (u32)available)) {
 		CT_ERROR(ct, "Incomplete message %*ph %*ph %*ph\n",
 			 4, &header,
@@ -667,6 +865,7 @@ static int ct_read(struct intel_guc_ct *ct, struct ct_incoming_msg **msg)
 			      size - head : available - 1), &cmds[head],
 			 4 * (head + available - 1 > size ?
 			      available - 1 - size + head : 0), &cmds[0]);
+		desc->status |= GUC_CTB_STATUS_UNDERFLOW;
 		goto corrupted;
 	}
 
@@ -689,65 +888,39 @@ static int ct_read(struct intel_guc_ct *ct, struct ct_incoming_msg **msg)
 	}
 	CT_DEBUG(ct, "received %*ph\n", 4 * len, (*msg)->msg);
 
-	desc->head = head * 4;
+	/* update local copies */
+	ctb->head = head;
+
+	/* now update descriptor */
+	WRITE_ONCE(desc->head, head);
+
 	return available - len;
 
 corrupted:
-	CT_ERROR(ct, "Corrupted descriptor addr=%#x head=%u tail=%u size=%u\n",
-		 desc->addr, desc->head, desc->tail, desc->size);
-	desc->is_in_error = 1;
+	CT_ERROR(ct, "Corrupted descriptor head=%u tail=%u status=%#x\n",
+		 desc->head, desc->tail, desc->status);
+	ctb->broken = true;
 	return -EPIPE;
 }
 
-/**
- * DOC: CTB GuC to Host response
- *
- * Format of the CTB GuC to Host response message is as follows::
- *
- *      +------------+---------+---------+---------+---------+---------+
- *      |   msg[0]   |   [1]   |   [2]   |   [3]   |   ...   |  [n-1]  |
- *      +------------+---------+---------+---------+---------+---------+
- *      |   MESSAGE  |       MESSAGE PAYLOAD                           |
- *      +   HEADER   +---------+---------+---------+---------+---------+
- *      |            |    0    |    1    |    2    |   ...   |    n    |
- *      +============+=========+=========+=========+=========+=========+
- *      |  len >= 2  |  FENCE  |  STATUS |   response specific data    |
- *      +------+-----+---------+---------+---------+---------+---------+
- *
- *                   ^-----------------------len-----------------------^
- */
-
 static int ct_handle_response(struct intel_guc_ct *ct, struct ct_incoming_msg *response)
 {
-	u32 header = response->msg[0];
-	u32 len = ct_header_get_len(header);
-	u32 fence;
-	u32 status;
-	u32 datalen;
+	u32 len = FIELD_GET(GUC_CTB_MSG_0_NUM_DWORDS, response->msg[0]);
+	u32 fence = FIELD_GET(GUC_CTB_MSG_0_FENCE, response->msg[0]);
+	const u32 *hxg = &response->msg[GUC_CTB_MSG_MIN_LEN];
+	const u32 *data = &hxg[GUC_HXG_MSG_MIN_LEN];
+	u32 datalen = len - GUC_HXG_MSG_MIN_LEN;
 	struct ct_request *req;
 	unsigned long flags;
 	bool found = false;
 	int err = 0;
 
-	GEM_BUG_ON(!ct_header_is_response(header));
-
-	/* Response payload shall at least include fence and status */
-	if (unlikely(len < 2)) {
-		CT_ERROR(ct, "Corrupted response (len %u)\n", len);
-		return -EPROTO;
-	}
-
-	fence = response->msg[1];
-	status = response->msg[2];
-	datalen = len - 2;
-
-	/* Format of the status follows RESPONSE message */
-	if (unlikely(!INTEL_GUC_MSG_IS_RESPONSE(status))) {
-		CT_ERROR(ct, "Corrupted response (status %#x)\n", status);
-		return -EPROTO;
-	}
+	GEM_BUG_ON(len < GUC_HXG_MSG_MIN_LEN);
+	GEM_BUG_ON(FIELD_GET(GUC_HXG_MSG_0_ORIGIN, hxg[0]) != GUC_HXG_ORIGIN_GUC);
+	GEM_BUG_ON(FIELD_GET(GUC_HXG_MSG_0_TYPE, hxg[0]) != GUC_HXG_TYPE_RESPONSE_SUCCESS &&
+		   FIELD_GET(GUC_HXG_MSG_0_TYPE, hxg[0]) != GUC_HXG_TYPE_RESPONSE_FAILURE);
 
-	CT_DEBUG(ct, "response fence %u status %#x\n", fence, status);
+	CT_DEBUG(ct, "response fence %u status %#x\n", fence, hxg[0]);
 
 	spin_lock_irqsave(&ct->requests.lock, flags);
 	list_for_each_entry(req, &ct->requests.pending, link) {
@@ -763,18 +936,22 @@ static int ct_handle_response(struct intel_guc_ct *ct, struct ct_incoming_msg *r
 			err = -EMSGSIZE;
 		}
 		if (datalen)
-			memcpy(req->response_buf, response->msg + 3, 4 * datalen);
+			memcpy(req->response_buf, data, 4 * datalen);
 		req->response_len = datalen;
-		WRITE_ONCE(req->status, status);
+		WRITE_ONCE(req->status, hxg[0]);
 		found = true;
 		break;
 	}
-	spin_unlock_irqrestore(&ct->requests.lock, flags);
-
 	if (!found) {
 		CT_ERROR(ct, "Unsolicited response (fence %u)\n", fence);
-		return -ENOKEY;
+		CT_ERROR(ct, "Could not find fence=%u, last_fence=%u\n", fence,
+			 ct->requests.last_fence);
+		list_for_each_entry(req, &ct->requests.pending, link)
+			CT_ERROR(ct, "request %u awaits response\n",
+				 req->fence);
+		err = -ENOKEY;
 	}
+	spin_unlock_irqrestore(&ct->requests.lock, flags);
 
 	if (unlikely(err))
 		return err;
@@ -786,14 +963,16 @@ static int ct_handle_response(struct intel_guc_ct *ct, struct ct_incoming_msg *r
 static int ct_process_request(struct intel_guc_ct *ct, struct ct_incoming_msg *request)
 {
 	struct intel_guc *guc = ct_to_guc(ct);
-	u32 header, action, len;
+	const u32 *hxg;
 	const u32 *payload;
+	u32 hxg_len, action, len;
 	int ret;
 
-	header = request->msg[0];
-	payload = &request->msg[1];
-	action = ct_header_get_action(header);
-	len = ct_header_get_len(header);
+	hxg = &request->msg[GUC_CTB_MSG_MIN_LEN];
+	hxg_len = request->size - GUC_CTB_MSG_MIN_LEN;
+	payload = &hxg[GUC_HXG_MSG_MIN_LEN];
+	action = FIELD_GET(GUC_HXG_EVENT_MSG_0_ACTION, hxg[0]);
+	len = hxg_len - GUC_HXG_MSG_MIN_LEN;
 
 	CT_DEBUG(ct, "request %x %*ph\n", action, 4 * len, payload);
 
@@ -801,6 +980,19 @@ static int ct_process_request(struct intel_guc_ct *ct, struct ct_incoming_msg *r
 	case INTEL_GUC_ACTION_DEFAULT:
 		ret = intel_guc_to_host_process_recv_msg(guc, payload, len);
 		break;
+	case INTEL_GUC_ACTION_DEREGISTER_CONTEXT_DONE:
+		ret = intel_guc_deregister_done_process_msg(guc, payload,
+							    len);
+		break;
+	case INTEL_GUC_ACTION_SCHED_CONTEXT_MODE_DONE:
+		ret = intel_guc_sched_done_process_msg(guc, payload, len);
+		break;
+	case INTEL_GUC_ACTION_CONTEXT_RESET_NOTIFICATION:
+		ret = intel_guc_context_reset_process_msg(guc, payload, len);
+		break;
+	case INTEL_GUC_ACTION_ENGINE_FAILURE_NOTIFICATION:
+		ret = intel_guc_engine_failure_process_msg(guc, payload, len);
+		break;
 	default:
 		ret = -EOPNOTSUPP;
 		break;
@@ -855,29 +1047,24 @@ static void ct_incoming_request_worker_func(struct work_struct *w)
 		queue_work(system_unbound_wq, &ct->requests.worker);
 }
 
-/**
- * DOC: CTB GuC to Host request
- *
- * Format of the CTB GuC to Host request message is as follows::
- *
- *      +------------+---------+---------+---------+---------+---------+
- *      |   msg[0]   |   [1]   |   [2]   |   [3]   |   ...   |  [n-1]  |
- *      +------------+---------+---------+---------+---------+---------+
- *      |   MESSAGE  |       MESSAGE PAYLOAD                           |
- *      +   HEADER   +---------+---------+---------+---------+---------+
- *      |            |    0    |    1    |    2    |   ...   |    n    |
- *      +============+=========+=========+=========+=========+=========+
- *      |     len    |            request specific data                |
- *      +------+-----+---------+---------+---------+---------+---------+
- *
- *                   ^-----------------------len-----------------------^
- */
-
-static int ct_handle_request(struct intel_guc_ct *ct, struct ct_incoming_msg *request)
+static int ct_handle_event(struct intel_guc_ct *ct, struct ct_incoming_msg *request)
 {
+	const u32 *hxg = &request->msg[GUC_CTB_MSG_MIN_LEN];
+	u32 action = FIELD_GET(GUC_HXG_EVENT_MSG_0_ACTION, hxg[0]);
 	unsigned long flags;
 
-	GEM_BUG_ON(ct_header_is_response(request->msg[0]));
+	GEM_BUG_ON(FIELD_GET(GUC_HXG_MSG_0_TYPE, hxg[0]) != GUC_HXG_TYPE_EVENT);
+
+	/*
+	 * Adjusting the space must be done in IRQ or deadlock can occur as the
+	 * CTB processing in the below workqueue can send CTBs which creates a
+	 * circular dependency if the space was returned there.
+	 */
+	switch (action) {
+	case INTEL_GUC_ACTION_SCHED_CONTEXT_MODE_DONE:
+	case INTEL_GUC_ACTION_DEREGISTER_CONTEXT_DONE:
+		g2h_release_space(ct, request->size);
+	}
 
 	spin_lock_irqsave(&ct->requests.lock, flags);
 	list_add_tail(&request->link, &ct->requests.incoming);
@@ -887,15 +1074,53 @@ static int ct_handle_request(struct intel_guc_ct *ct, struct ct_incoming_msg *re
 	return 0;
 }
 
-static void ct_handle_msg(struct intel_guc_ct *ct, struct ct_incoming_msg *msg)
+static int ct_handle_hxg(struct intel_guc_ct *ct, struct ct_incoming_msg *msg)
 {
-	u32 header = msg->msg[0];
+	u32 origin, type;
+	u32 *hxg;
 	int err;
 
-	if (ct_header_is_response(header))
+	if (unlikely(msg->size < GUC_CTB_HXG_MSG_MIN_LEN))
+		return -EBADMSG;
+
+	hxg = &msg->msg[GUC_CTB_MSG_MIN_LEN];
+
+	origin = FIELD_GET(GUC_HXG_MSG_0_ORIGIN, hxg[0]);
+	if (unlikely(origin != GUC_HXG_ORIGIN_GUC)) {
+		err = -EPROTO;
+		goto failed;
+	}
+
+	type = FIELD_GET(GUC_HXG_MSG_0_TYPE, hxg[0]);
+	switch (type) {
+	case GUC_HXG_TYPE_EVENT:
+		err = ct_handle_event(ct, msg);
+		break;
+	case GUC_HXG_TYPE_RESPONSE_SUCCESS:
+	case GUC_HXG_TYPE_RESPONSE_FAILURE:
 		err = ct_handle_response(ct, msg);
+		break;
+	default:
+		err = -EOPNOTSUPP;
+	}
+
+	if (unlikely(err)) {
+failed:
+		CT_ERROR(ct, "Failed to handle HXG message (%pe) %*ph\n",
+			 ERR_PTR(err), 4 * GUC_HXG_MSG_MIN_LEN, hxg);
+	}
+	return err;
+}
+
+static void ct_handle_msg(struct intel_guc_ct *ct, struct ct_incoming_msg *msg)
+{
+	u32 format = FIELD_GET(GUC_CTB_MSG_0_FORMAT, msg->msg[0]);
+	int err;
+
+	if (format == GUC_CTB_FORMAT_HXG)
+		err = ct_handle_hxg(ct, msg);
 	else
-		err = ct_handle_request(ct, msg);
+		err = -EOPNOTSUPP;
 
 	if (unlikely(err)) {
 		CT_ERROR(ct, "Failed to process CT message (%pe) %*ph\n",
@@ -958,3 +1183,25 @@ void intel_guc_ct_event_handler(struct intel_guc_ct *ct)
 
 	ct_try_receive_message(ct);
 }
+
+void intel_guc_ct_print_info(struct intel_guc_ct *ct,
+			     struct drm_printer *p)
+{
+	drm_printf(p, "CT %s\n", enableddisabled(ct->enabled));
+
+	if (!ct->enabled)
+		return;
+
+	drm_printf(p, "H2G Space: %u\n",
+		   atomic_read(&ct->ctbs.send.space) * 4);
+	drm_printf(p, "Head: %u\n",
+		   ct->ctbs.send.desc->head);
+	drm_printf(p, "Tail: %u\n",
+		   ct->ctbs.send.desc->tail);
+	drm_printf(p, "G2H Space: %u\n",
+		   atomic_read(&ct->ctbs.recv.space) * 4);
+	drm_printf(p, "Head: %u\n",
+		   ct->ctbs.recv.desc->head);
+	drm_printf(p, "Tail: %u\n",
+		   ct->ctbs.recv.desc->tail);
+}