disp: msm: dsi: batching multiple DSI commands using debugfs node

The change batches DSI commands sent using the debugfs node, in a
separate buffer from the TX command buffer to ensure that they are not
triggered before the last command bit is set. Once the last command
bit is set the buffer is then copied to the DSI TX buffer and triggered.

Change-Id: I9ba624e4e19341696a974994817603315c6c8a45
Signed-off-by: Satya Rama Aditya Pinapala <psraditya30@codeaurora.org>

msm/dsi/dsi_display.c

@@ -36,6 +36,7 @@
 
 #define SEC_PANEL_NAME_MAX_LEN  256
 
+u8 dbgfs_tx_cmd_buf[SZ_4K];
 static char dsi_display_primary[MAX_CMDLINE_PARAM_LEN];
 static char dsi_display_secondary[MAX_CMDLINE_PARAM_LEN];
 static struct dsi_display_boot_param boot_displays[MAX_DSI_ACTIVE_DISPLAY] = {
@@ -1014,10 +1015,9 @@ int dsi_display_cmd_transfer(struct drm_connector *connector,
 		u32 cmd_buf_len)
 {
 	struct dsi_display *dsi_display = display;
-	struct dsi_cmd_desc cmd;
-	u8 cmd_payload[MAX_CMD_PAYLOAD_SIZE];
-	int rc = 0;
-	bool state = false;
+	int rc = 0, cnt = 0, i = 0;
+	bool state = false, transfer = false;
+	struct dsi_panel_cmd_set *set;
 
 	if (!dsi_display || !cmd_buf) {
 		DSI_ERR("[DSI] invalid params\n");
@@ -1026,12 +1026,8 @@ int dsi_display_cmd_transfer(struct drm_connector *connector,
 
 	DSI_DEBUG("[DSI] Display command transfer\n");
 
-	rc = dsi_display_cmd_prepare(cmd_buf, cmd_buf_len,
-			&cmd, cmd_payload, MAX_CMD_PAYLOAD_SIZE);
-	if (rc) {
-		DSI_ERR("[DSI] command prepare failed. rc %d\n", rc);
-		return rc;
-	}
+	if ((cmd_buf[1]) || (cmd_buf[3] & MIPI_DSI_MSG_LASTCOMMAND))
+		transfer = true;
 
 	mutex_lock(&dsi_display->display_lock);
 	rc = dsi_display_ctrl_get_host_init_state(dsi_display, &state);
@@ -1053,8 +1049,59 @@ int dsi_display_cmd_transfer(struct drm_connector *connector,
 		goto end;
 	}
 
-	rc = dsi_display->host.ops->transfer(&dsi_display->host,
-			&cmd.msg);
+	/*
+	 * Reset the dbgfs buffer if the commands sent exceed the available
+	 * buffer size. For video mode, limiting the buffer size to 2K to
+	 * ensure no performance issues.
+	 */
+	if (dsi_display->panel->panel_mode == DSI_OP_CMD_MODE) {
+		if ((dsi_display->tx_cmd_buf_ndx + cmd_buf_len) > SZ_4K) {
+			memset(dbgfs_tx_cmd_buf, 0, SZ_4K);
+			dsi_display->tx_cmd_buf_ndx = 0;
+		}
+	} else {
+		if ((dsi_display->tx_cmd_buf_ndx + cmd_buf_len) > SZ_2K) {
+			memset(dbgfs_tx_cmd_buf, 0, SZ_4K);
+			dsi_display->tx_cmd_buf_ndx = 0;
+		}
+	}
+
+	memcpy(&dbgfs_tx_cmd_buf[dsi_display->tx_cmd_buf_ndx], cmd_buf,
+			cmd_buf_len);
+	dsi_display->tx_cmd_buf_ndx += cmd_buf_len;
+	if (transfer) {
+		struct dsi_cmd_desc *cmds;
+
+		set = &dsi_display->cmd_set;
+		set->count = 0;
+		dsi_panel_get_cmd_pkt_count(dbgfs_tx_cmd_buf,
+				dsi_display->tx_cmd_buf_ndx, &cnt);
+		dsi_panel_alloc_cmd_packets(set, cnt);
+		dsi_panel_create_cmd_packets(dbgfs_tx_cmd_buf,
+				dsi_display->tx_cmd_buf_ndx, cnt, set->cmds);
+		cmds = set->cmds;
+		dsi_display->tx_cmd_buf_ndx = 0;
+
+		for (i = 0; i < cnt; i++) {
+			if (cmds->last_command)
+				cmds->msg.flags |= MIPI_DSI_MSG_LASTCOMMAND;
+			rc = dsi_display->host.ops->transfer(&dsi_display->host,
+					&cmds->msg);
+			if (rc < 0) {
+				DSI_ERR("failed to send command, rc=%d\n", rc);
+				goto end;
+			}
+			if (cmds->post_wait_ms)
+				usleep_range(cmds->post_wait_ms*1000,
+						((cmds->post_wait_ms*1000)+10));
+			cmds++;
+		}
+
+		memset(dbgfs_tx_cmd_buf, 0, SZ_4K);
+		dsi_panel_destroy_cmd_packets(set);
+		dsi_panel_dealloc_cmd_packets(set);
+	}
+
 end:
 	mutex_unlock(&dsi_display->display_lock);
 	return rc;