drm/i915/guc: Only rely on own CTB size

In upcoming GuC firmware, CTB size will be removed from the CTB
descriptor so we must keep it locally for any calculations.

While around, improve some debug messages and helpers.
Signed-off-by: Michal Wajdeczko <michal.wajdeczko@intel.com>
Signed-off-by: Matthew Brost <matthew.brost@intel.com>
Reviewed-by: Matthew Brost <matthew.brost@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/20210603051630.2635-10-matthew.brost@intel.com

drivers/gpu/drm/i915/gt/uc/intel_guc_ct.c

@@ -90,6 +90,24 @@ static void guc_ct_buffer_desc_init(struct guc_ct_buffer_desc *desc,
 	desc->owner = CTB_OWNER_HOST;
 }
 
+static void guc_ct_buffer_reset(struct intel_guc_ct_buffer *ctb, u32 cmds_addr)
+{
+	guc_ct_buffer_desc_init(ctb->desc, cmds_addr, ctb->size);
+}
+
+static void guc_ct_buffer_init(struct intel_guc_ct_buffer *ctb,
+			       struct guc_ct_buffer_desc *desc,
+			       u32 *cmds, u32 size)
+{
+	GEM_BUG_ON(size % 4);
+
+	ctb->desc = desc;
+	ctb->cmds = cmds;
+	ctb->size = size;
+
+	guc_ct_buffer_reset(ctb, 0);
+}
+
 static int guc_action_register_ct_buffer(struct intel_guc *guc,
 					 u32 desc_addr,
 					 u32 type)
@@ -148,7 +166,10 @@ static int ct_deregister_buffer(struct intel_guc_ct *ct, u32 type)
 int intel_guc_ct_init(struct intel_guc_ct *ct)
 {
 	struct intel_guc *guc = ct_to_guc(ct);
+	struct guc_ct_buffer_desc *desc;
+	u32 blob_size;
 	void *blob;
+	u32 *cmds;
 	int err;
 	int i;
 
@@ -176,19 +197,24 @@ int intel_guc_ct_init(struct intel_guc_ct *ct)
 	 * other code will need updating as well.
 	 */
 
-	err = intel_guc_allocate_and_map_vma(guc, PAGE_SIZE, &ct->vma, &blob);
+	blob_size = PAGE_SIZE;
+	err = intel_guc_allocate_and_map_vma(guc, blob_size, &ct->vma, &blob);
 	if (unlikely(err)) {
-		CT_ERROR(ct, "Failed to allocate CT channel (err=%d)\n", err);
+		CT_PROBE_ERROR(ct, "Failed to allocate %u for CTB data (%pe)\n",
+			       blob_size, ERR_PTR(err));
 		return err;
 	}
 
-	CT_DEBUG(ct, "vma base=%#x\n", intel_guc_ggtt_offset(guc, ct->vma));
+	CT_DEBUG(ct, "base=%#x size=%u\n", intel_guc_ggtt_offset(guc, ct->vma), blob_size);
 
 	/* store pointers to desc and cmds */
 	for (i = 0; i < ARRAY_SIZE(ct->ctbs); i++) {
 		GEM_BUG_ON((i !=  CTB_SEND) && (i != CTB_RECV));
-		ct->ctbs[i].desc = blob + PAGE_SIZE/4 * i;
-		ct->ctbs[i].cmds = blob + PAGE_SIZE/4 * i + PAGE_SIZE/2;
+
+		desc = blob + PAGE_SIZE / 4 * i;
+		cmds = blob + PAGE_SIZE / 4 * i + PAGE_SIZE / 2;
+
+		guc_ct_buffer_init(&ct->ctbs[i], desc, cmds, PAGE_SIZE / 4);
 	}
 
 	return 0;
@@ -217,7 +243,7 @@ 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, size;
+	u32 base, cmds;
 	int err;
 	int i;
 
@@ -232,10 +258,11 @@ int intel_guc_ct_enable(struct intel_guc_ct *ct)
 	 */
 	for (i = 0; i < ARRAY_SIZE(ct->ctbs); i++) {
 		GEM_BUG_ON((i != CTB_SEND) && (i != CTB_RECV));
+
 		cmds = base + PAGE_SIZE / 4 * i + PAGE_SIZE / 2;
-		size = PAGE_SIZE / 4;
-		CT_DEBUG(ct, "%d: addr=%#x size=%u\n", i, cmds, size);
-		guc_ct_buffer_desc_init(ct->ctbs[i].desc, cmds, size);
+		CT_DEBUG(ct, "%d: cmds addr=%#x\n", i, cmds);
+
+		guc_ct_buffer_reset(&ct->ctbs[i], cmds);
 	}
 
 	/*
@@ -259,7 +286,7 @@ int intel_guc_ct_enable(struct intel_guc_ct *ct)
 err_deregister:
 	ct_deregister_buffer(ct, INTEL_GUC_CT_BUFFER_TYPE_RECV);
 err_out:
-	CT_PROBE_ERROR(ct, "Failed to open channel (err=%d)\n", err);
+	CT_PROBE_ERROR(ct, "Failed to enable CTB (%pe)\n", ERR_PTR(err));
 	return err;
 }
 
@@ -314,7 +341,7 @@ static int ct_write(struct intel_guc_ct *ct,
 	struct guc_ct_buffer_desc *desc = ctb->desc;
 	u32 head = desc->head;
 	u32 tail = desc->tail;
-	u32 size = desc->size;
+	u32 size = ctb->size;
 	u32 used;
 	u32 header;
 	u32 *cmds = ctb->cmds;
@@ -323,7 +350,7 @@ static int ct_write(struct intel_guc_ct *ct,
 	if (unlikely(desc->is_in_error))
 		return -EPIPE;
 
-	if (unlikely(!IS_ALIGNED(head | tail | size, 4) ||
+	if (unlikely(!IS_ALIGNED(head | tail, 4) ||
 		     (tail | head) >= size))
 		goto corrupted;
 
@@ -530,7 +557,7 @@ static int ct_read(struct intel_guc_ct *ct, u32 *data)
 	struct guc_ct_buffer_desc *desc = ctb->desc;
 	u32 head = desc->head;
 	u32 tail = desc->tail;
-	u32 size = desc->size;
+	u32 size = ctb->size;
 	u32 *cmds = ctb->cmds;
 	s32 available;
 	unsigned int len;
@@ -539,7 +566,7 @@ static int ct_read(struct intel_guc_ct *ct, u32 *data)
 	if (unlikely(desc->is_in_error))
 		return -EPIPE;
 
-	if (unlikely(!IS_ALIGNED(head | tail | size, 4) ||
+	if (unlikely(!IS_ALIGNED(head | tail, 4) ||
 		     (tail | head) >= size))
 		goto corrupted;
 

drivers/gpu/drm/i915/gt/uc/intel_guc_ct.h

@@ -29,10 +29,12 @@ struct intel_guc;
  *
  * @desc: pointer to the buffer descriptor
  * @cmds: pointer to the commands buffer
+ * @size: size of the commands buffer
  */
 struct intel_guc_ct_buffer {
 	struct guc_ct_buffer_desc *desc;
 	u32 *cmds;
+	u32 size;
 };