drm/xe/guc: Use HXG definitions on HXG messages

While parsing and processing CTB G2H messages we should extract
underlying HXG message and use HXG definitions on such message.
Using outer CTB layer message in HXG definitions require use of
shifted dword index, which might be confusing:

	FIELD_GET(GUC_HXG_MSG_0_xxx, msg[1])

instead of:

	FIELD_GET(GUC_HXG_MSG_0_xxx, hxg[0])

Cc: Matthew Brost <matthew.brost@intel.com>
Reviewed-by: Matthew Brost <matthew.brost@intel.com>
Link: https://lore.kernel.org/r/20240111210632.717-1-michal.wajdeczko@intel.comSigned-off-by: Michal Wajdeczko <michal.wajdeczko@intel.com>

drivers/gpu/drm/xe/xe_guc_ct.c

@@ -796,9 +796,20 @@ int xe_guc_ct_send_recv_no_fail(struct xe_guc_ct *ct, const u32 *action,
 	return guc_ct_send_recv(ct, action, len, response_buffer, true);
 }
 
+static u32 *msg_to_hxg(u32 *msg)
+{
+	return msg + GUC_CTB_MSG_MIN_LEN;
+}
+
+static u32 msg_len_to_hxg_len(u32 len)
+{
+	return len - GUC_CTB_MSG_MIN_LEN;
+}
+
 static int parse_g2h_event(struct xe_guc_ct *ct, u32 *msg, u32 len)
 {
-	u32 action = FIELD_GET(GUC_HXG_EVENT_MSG_0_ACTION, msg[1]);
+	u32 *hxg = msg_to_hxg(msg);
+	u32 action = FIELD_GET(GUC_HXG_EVENT_MSG_0_ACTION, hxg[0]);
 
 	lockdep_assert_held(&ct->lock);
 
@@ -817,9 +828,10 @@ static int parse_g2h_response(struct xe_guc_ct *ct, u32 *msg, u32 len)
 {
 	struct xe_gt *gt =  ct_to_gt(ct);
 	struct xe_device *xe = gt_to_xe(gt);
-	u32 response_len = len - GUC_CTB_MSG_MIN_LEN;
+	u32 *hxg = msg_to_hxg(msg);
+	u32 hxg_len = msg_len_to_hxg_len(len);
 	u32 fence = FIELD_GET(GUC_CTB_MSG_0_FENCE, msg[0]);
-	u32 type = FIELD_GET(GUC_HXG_MSG_0_TYPE, msg[1]);
+	u32 type = FIELD_GET(GUC_HXG_MSG_0_TYPE, hxg[0]);
 	struct g2h_fence *g2h_fence;
 
 	lockdep_assert_held(&ct->lock);
@@ -836,8 +848,8 @@ static int parse_g2h_response(struct xe_guc_ct *ct, u32 *msg, u32 len)
 		if (type == GUC_HXG_TYPE_RESPONSE_FAILURE)
 			xe_gt_err(gt, "FAST_REQ H2G fence 0x%x failed! e=0x%x, h=%u\n",
 				  fence,
-				  FIELD_GET(GUC_HXG_FAILURE_MSG_0_ERROR, msg[1]),
-				  FIELD_GET(GUC_HXG_FAILURE_MSG_0_HINT, msg[1]));
+				  FIELD_GET(GUC_HXG_FAILURE_MSG_0_ERROR, hxg[0]),
+				  FIELD_GET(GUC_HXG_FAILURE_MSG_0_HINT, hxg[0]));
 		else
 			xe_gt_err(gt, "unexpected response %u for FAST_REQ H2G fence 0x%x!\n",
 				  type, fence);
@@ -857,18 +869,14 @@ static int parse_g2h_response(struct xe_guc_ct *ct, u32 *msg, u32 len)
 
 	if (type == GUC_HXG_TYPE_RESPONSE_FAILURE) {
 		g2h_fence->fail = true;
-		g2h_fence->error =
-			FIELD_GET(GUC_HXG_FAILURE_MSG_0_ERROR, msg[1]);
-		g2h_fence->hint =
-			FIELD_GET(GUC_HXG_FAILURE_MSG_0_HINT, msg[1]);
+		g2h_fence->error = FIELD_GET(GUC_HXG_FAILURE_MSG_0_ERROR, hxg[0]);
+		g2h_fence->hint = FIELD_GET(GUC_HXG_FAILURE_MSG_0_HINT, hxg[0]);
 	} else if (type == GUC_HXG_TYPE_NO_RESPONSE_RETRY) {
 		g2h_fence->retry = true;
-		g2h_fence->reason =
-			FIELD_GET(GUC_HXG_RETRY_MSG_0_REASON, msg[1]);
+		g2h_fence->reason = FIELD_GET(GUC_HXG_RETRY_MSG_0_REASON, hxg[0]);
 	} else if (g2h_fence->response_buffer) {
-		g2h_fence->response_len = response_len;
-		memcpy(g2h_fence->response_buffer, msg + GUC_CTB_MSG_MIN_LEN,
-		       response_len * sizeof(u32));
+		g2h_fence->response_len = hxg_len;
+		memcpy(g2h_fence->response_buffer, hxg, hxg_len * sizeof(u32));
 	}
 
 	g2h_release_space(ct, GUC_CTB_HXG_MSG_MAX_LEN);
@@ -884,14 +892,13 @@ static int parse_g2h_response(struct xe_guc_ct *ct, u32 *msg, u32 len)
 static int parse_g2h_msg(struct xe_guc_ct *ct, u32 *msg, u32 len)
 {
 	struct xe_device *xe = ct_to_xe(ct);
-	u32 hxg, origin, type;
+	u32 *hxg = msg_to_hxg(msg);
+	u32 origin, type;
 	int ret;
 
 	lockdep_assert_held(&ct->lock);
 
-	hxg = msg[1];
-
-	origin = FIELD_GET(GUC_HXG_MSG_0_ORIGIN, hxg);
+	origin = FIELD_GET(GUC_HXG_MSG_0_ORIGIN, hxg[0]);
 	if (unlikely(origin != GUC_HXG_ORIGIN_GUC)) {
 		drm_err(&xe->drm,
 			"G2H channel broken on read, origin=%d, reset required\n",
@@ -901,7 +908,7 @@ static int parse_g2h_msg(struct xe_guc_ct *ct, u32 *msg, u32 len)
 		return -EPROTO;
 	}
 
-	type = FIELD_GET(GUC_HXG_MSG_0_TYPE, hxg);
+	type = FIELD_GET(GUC_HXG_MSG_0_TYPE, hxg[0]);
 	switch (type) {
 	case GUC_HXG_TYPE_EVENT:
 		ret = parse_g2h_event(ct, msg, len);
@@ -927,14 +934,19 @@ static int process_g2h_msg(struct xe_guc_ct *ct, u32 *msg, u32 len)
 {
 	struct xe_device *xe = ct_to_xe(ct);
 	struct xe_guc *guc = ct_to_guc(ct);
-	u32 action = FIELD_GET(GUC_HXG_EVENT_MSG_0_ACTION, msg[1]);
-	u32 *payload = msg + GUC_CTB_HXG_MSG_MIN_LEN;
-	u32 adj_len = len - GUC_CTB_HXG_MSG_MIN_LEN;
+	u32 hxg_len = msg_len_to_hxg_len(len);
+	u32 *hxg = msg_to_hxg(msg);
+	u32 action, adj_len;
+	u32 *payload;
 	int ret = 0;
 
-	if (FIELD_GET(GUC_HXG_MSG_0_TYPE, msg[1]) != GUC_HXG_TYPE_EVENT)
+	if (FIELD_GET(GUC_HXG_MSG_0_TYPE, hxg[0]) != GUC_HXG_TYPE_EVENT)
 		return 0;
 
+	action = FIELD_GET(GUC_HXG_EVENT_MSG_0_ACTION, hxg[0]);
+	payload = hxg + GUC_HXG_EVENT_MSG_MIN_LEN;
+	adj_len = hxg_len - GUC_HXG_EVENT_MSG_MIN_LEN;
+
 	switch (action) {
 	case XE_GUC_ACTION_SCHED_CONTEXT_MODE_DONE:
 		ret = xe_guc_sched_done_handler(guc, payload, adj_len);
@@ -995,6 +1007,7 @@ static int g2h_read(struct xe_guc_ct *ct, u32 *msg, bool fast_path)
 	u32 tail, head, len;
 	s32 avail;
 	u32 action;
+	u32 *hxg;
 
 	lockdep_assert_held(&ct->fast_lock);
 
@@ -1045,10 +1058,11 @@ static int g2h_read(struct xe_guc_ct *ct, u32 *msg, bool fast_path)
 				   avail * sizeof(u32));
 	}
 
-	action = FIELD_GET(GUC_HXG_EVENT_MSG_0_ACTION, msg[1]);
+	hxg = msg_to_hxg(msg);
+	action = FIELD_GET(GUC_HXG_EVENT_MSG_0_ACTION, hxg[0]);
 
 	if (fast_path) {
-		if (FIELD_GET(GUC_HXG_MSG_0_TYPE, msg[1]) != GUC_HXG_TYPE_EVENT)
+		if (FIELD_GET(GUC_HXG_MSG_0_TYPE, hxg[0]) != GUC_HXG_TYPE_EVENT)
 			return 0;
 
 		switch (action) {
@@ -1074,9 +1088,11 @@ static void g2h_fast_path(struct xe_guc_ct *ct, u32 *msg, u32 len)
 {
 	struct xe_device *xe = ct_to_xe(ct);
 	struct xe_guc *guc = ct_to_guc(ct);
-	u32 action = FIELD_GET(GUC_HXG_EVENT_MSG_0_ACTION, msg[1]);
-	u32 *payload = msg + GUC_CTB_HXG_MSG_MIN_LEN;
-	u32 adj_len = len - GUC_CTB_HXG_MSG_MIN_LEN;
+	u32 hxg_len = msg_len_to_hxg_len(len);
+	u32 *hxg = msg_to_hxg(msg);
+	u32 action = FIELD_GET(GUC_HXG_EVENT_MSG_0_ACTION, hxg[0]);
+	u32 *payload = hxg + GUC_HXG_MSG_MIN_LEN;
+	u32 adj_len = hxg_len - GUC_HXG_MSG_MIN_LEN;
 	int ret = 0;
 
 	switch (action) {