disp: msm: dsi: trigger broadcast commands using DMA start window

As per the HW requirements it is highly recommended to use DMA start
window to trigger  broadcast commands. If not used then it can
result in a hardware hang with the DSI controllers going out
of sync. This behavior is even more prominent in cases of higher
refresh rates. As part of the change we change the default DMA
scheduling behavior to default to maximum possible DMA window
in case it is not specified in the panel device tree.

Change-Id: Ied4df9063664cedbc18ce009054d4e5ecae30ab2
Signed-off-by: Satya Rama Aditya Pinapala <[email protected]>

msm/dsi/dsi_ctrl.c

@@ -1319,17 +1319,16 @@ static void dsi_configure_command_scheduling(struct dsi_ctrl *dsi_ctrl,
 	}
 
 	/*
-	 * In case of command scheduling in command mode, the window size
-	 * is reset to zero, if the total scheduling window is greater
-	 * than the panel height.
+	 * In case of command scheduling in command mode, set the maximum
+	 * possible size of the DMA start window in case no schedule line and
+	 * window size properties are defined by the panel.
 	 */
 	if ((dsi_ctrl->host_config.panel_mode == DSI_OP_CMD_MODE) &&
 			dsi_hw_ops.configure_cmddma_window) {
-		sched_line_no = line_no;
-
-		if ((sched_line_no + window) > timing->v_active)
-			window = 0;
 
+		sched_line_no = (line_no == 0) ? TEARCHECK_WINDOW_SIZE :
+					line_no;
+		window = (window == 0) ? timing->v_active : window;
 		sched_line_no += timing->v_active;
 
 		dsi_hw_ops.configure_cmddma_window(&dsi_ctrl->hw, cmd_mem,

msm/dsi/dsi_ctrl.h

@@ -53,6 +53,9 @@
 /* max size supported for dsi cmd transfer using TPG */
 #define DSI_CTRL_MAX_CMD_FIFO_STORE_SIZE 64
 
+/*Default tearcheck window size as programmed by MDP*/
+#define TEARCHECK_WINDOW_SIZE	5
+
 /**
  * enum dsi_power_state - defines power states for dsi controller.
  * @DSI_CTRL_POWER_VREG_OFF:    Digital and analog supplies for DSI controller

msm/dsi/dsi_ctrl_hw_2_2.c

@@ -202,9 +202,6 @@ void dsi_ctrl_hw_22_configure_cmddma_window(struct dsi_ctrl_hw *ctrl,
 {
 	u32 reg = 0;
 
-	if (!window)
-		return;
-
 	if (cmd->en_broadcast) {
 		reg = DSI_R32(ctrl, DSI_TRIG_CTRL);
 		if (cmd->is_master) {

msm/dsi/dsi_display.c

@@ -995,7 +995,7 @@ static int dsi_display_cmd_rx(struct dsi_display *display,
 	flags |= (DSI_CTRL_CMD_FETCH_MEMORY | DSI_CTRL_CMD_READ);
 	if ((m_ctrl->ctrl->host_config.panel_mode == DSI_OP_VIDEO_MODE) ||
 			((cmd->msg.flags & MIPI_DSI_MSG_CMD_DMA_SCHED) &&
-			 (display->panel->panel_initialized)))
+			 (display->enabled)))
 		flags |= DSI_CTRL_CMD_CUSTOM_DMA_SCHED;
 
 	rc = dsi_ctrl_cmd_transfer(m_ctrl->ctrl, &cmd->msg, &flags);
@@ -3084,8 +3084,12 @@ static int dsi_display_broadcast_cmd(struct dsi_display *display,
 		m_flags |= DSI_CTRL_CMD_LAST_COMMAND;
 	}
 
-	if ((msg->flags & MIPI_DSI_MSG_CMD_DMA_SCHED) &&
-				(display->panel->panel_initialized)) {
+	/*
+	 * During broadcast command dma scheduling is always recommended.
+	 * As long as the display is enabled and TE is running the
+	 * DSI_CTRL_CMD_CUSTOM_DMA_SCHED flag should be set.
+	 */
+	if (display->enabled) {
 		flags |= DSI_CTRL_CMD_CUSTOM_DMA_SCHED;
 		m_flags |= DSI_CTRL_CMD_CUSTOM_DMA_SCHED;
 	}
@@ -3261,7 +3265,7 @@ static ssize_t dsi_host_transfer(struct mipi_dsi_host *host,
 			cmd_flags |= DSI_CTRL_CMD_ASYNC_WAIT;
 
 		if ((msg->flags & MIPI_DSI_MSG_CMD_DMA_SCHED) &&
-				(display->panel->panel_initialized))
+				(display->enabled))
 			cmd_flags |= DSI_CTRL_CMD_CUSTOM_DMA_SCHED;
 
 		rc = dsi_ctrl_cmd_transfer(display->ctrl[ctrl_idx].ctrl, msg,

msm/dsi/dsi_display.h

@@ -194,6 +194,7 @@ struct dsi_display_ext_bridge {
  *                    Set to false, otherwise.
  * @tx_cmd_buf_ndx:   Index to the DSI debugfs TX CMD buffer.
  * @cmd_set:	      Debugfs TX cmd set.
+ * @enabled:	      Boolean to indicate display enabled.
  */
 struct dsi_display {
 	struct platform_device *pdev;
@@ -292,6 +293,8 @@ struct dsi_display {
 
 	int tx_cmd_buf_ndx;
 	struct dsi_panel_cmd_set cmd_set;
+
+	bool enabled;
 };
 
 int dsi_display_dev_probe(struct platform_device *pdev);

msm/dsi/dsi_drm.c

@@ -246,6 +246,9 @@ static void dsi_bridge_enable(struct drm_bridge *bridge)
 		DSI_ERR("[%d] DSI display post enabled failed, rc=%d\n",
 		       c_bridge->id, rc);
 
+	if (display)
+		display->enabled = true;
+
 	if (display && display->drm_conn) {
 		sde_connector_helper_bridge_enable(display->drm_conn);
 		if (c_bridge->dsi_mode.dsi_mode_flags & DSI_MODE_FLAG_POMS)
@@ -269,6 +272,9 @@ static void dsi_bridge_disable(struct drm_bridge *bridge)
 	private_flags =
 		bridge->encoder->crtc->state->adjusted_mode.private_flags;
 
+	if (display)
+		display->enabled = false;
+
 	if (display && display->drm_conn) {
 		display->poms_pending =
 			private_flags & MSM_MODE_FLAG_SEAMLESS_POMS;