1 files changed, 160 insertions, 116 deletions

diff --git a/drivers/gpu/drm/mcde/mcde_dsi.c b/drivers/gpu/drm/mcde/mcde_dsi.c
index 981923caa7e6..2314c8122992 100644
--- a/drivers/gpu/drm/mcde/mcde_dsi.c
+++ b/drivers/gpu/drm/mcde/mcde_dsi.c
@@ -43,6 +43,7 @@ struct mcde_dsi {
 	struct drm_bridge *bridge_out;
 	struct mipi_dsi_host dsi_host;
 	struct mipi_dsi_device *mdsi;
+	const struct drm_display_mode *mode;
 	struct clk *hs_clk;
 	struct clk *lp_clk;
 	unsigned long hs_freq;
@@ -148,9 +149,22 @@ static void mcde_dsi_attach_to_mcde(struct mcde_dsi *d)
 {
 	d->mcde->mdsi = d->mdsi;
 
-	d->mcde->video_mode = !!(d->mdsi->mode_flags & MIPI_DSI_MODE_VIDEO);
-	/* Enable use of the TE signal for all command mode panels */
-	d->mcde->te_sync = !d->mcde->video_mode;
+	/*
+	 * Select the way the DSI data flow is pushing to the display:
+	 * currently we just support video or command mode depending
+	 * on the type of display. Video mode defaults to using the
+	 * formatter itself for synchronization (stateless video panel).
+	 *
+	 * FIXME: add flags to struct mipi_dsi_device .flags to indicate
+	 * displays that require BTA (bus turn around) so we can handle
+	 * such displays as well. Figure out how to properly handle
+	 * single frame on-demand updates with DRM for command mode
+	 * displays (MCDE_COMMAND_ONESHOT_FLOW).
+	 */
+	if (d->mdsi->mode_flags & MIPI_DSI_MODE_VIDEO)
+		d->mcde->flow_mode = MCDE_VIDEO_FORMATTER_FLOW;
+	else
+		d->mcde->flow_mode = MCDE_COMMAND_TE_FLOW;
 }
 
 static int mcde_dsi_host_attach(struct mipi_dsi_host *host,
@@ -194,79 +208,16 @@ static int mcde_dsi_host_detach(struct mipi_dsi_host *host,
 	 (type == MIPI_DSI_GENERIC_READ_REQUEST_2_PARAM) || \
 	 (type == MIPI_DSI_DCS_READ))
 
-static ssize_t mcde_dsi_host_transfer(struct mipi_dsi_host *host,
-				      const struct mipi_dsi_msg *msg)
+static int mcde_dsi_execute_transfer(struct mcde_dsi *d,
+				     const struct mipi_dsi_msg *msg)
 {
-	struct mcde_dsi *d = host_to_mcde_dsi(host);
 	const u32 loop_delay_us = 10; /* us */
-	const u8 *tx = msg->tx_buf;
 	u32 loop_counter;
 	size_t txlen = msg->tx_len;
 	size_t rxlen = msg->rx_len;
+	int i;
 	u32 val;
 	int ret;
-	int i;
-
-	if (txlen > 16) {
-		dev_err(d->dev,
-			"dunno how to write more than 16 bytes yet\n");
-		return -EIO;
-	}
-	if (rxlen > 4) {
-		dev_err(d->dev,
-			"dunno how to read more than 4 bytes yet\n");
-		return -EIO;
-	}
-
-	dev_dbg(d->dev,
-		"message to channel %d, write %zd bytes read %zd bytes\n",
-		msg->channel, txlen, rxlen);
-
-	/* Command "nature" */
-	if (MCDE_DSI_HOST_IS_READ(msg->type))
-		/* MCTL_MAIN_DATA_CTL already set up */
-		val = DSI_DIRECT_CMD_MAIN_SETTINGS_CMD_NAT_READ;
-	else
-		val = DSI_DIRECT_CMD_MAIN_SETTINGS_CMD_NAT_WRITE;
-	/*
-	 * More than 2 bytes will not fit in a single packet, so it's
-	 * time to set the "long not short" bit. One byte is used by
-	 * the MIPI DCS command leaving just one byte for the payload
-	 * in a short package.
-	 */
-	if (mipi_dsi_packet_format_is_long(msg->type))
-		val |= DSI_DIRECT_CMD_MAIN_SETTINGS_CMD_LONGNOTSHORT;
-	val |= 0 << DSI_DIRECT_CMD_MAIN_SETTINGS_CMD_ID_SHIFT;
-	val |= txlen << DSI_DIRECT_CMD_MAIN_SETTINGS_CMD_SIZE_SHIFT;
-	val |= DSI_DIRECT_CMD_MAIN_SETTINGS_CMD_LP_EN;
-	val |= msg->type << DSI_DIRECT_CMD_MAIN_SETTINGS_CMD_HEAD_SHIFT;
-	writel(val, d->regs + DSI_DIRECT_CMD_MAIN_SETTINGS);
-
-	/* MIPI DCS command is part of the data */
-	if (txlen > 0) {
-		val = 0;
-		for (i = 0; i < 4 && i < txlen; i++)
-			val |= tx[i] << (i * 8);
-	}
-	writel(val, d->regs + DSI_DIRECT_CMD_WRDAT0);
-	if (txlen > 4) {
-		val = 0;
-		for (i = 0; i < 4 && (i + 4) < txlen; i++)
-			val |= tx[i + 4] << (i * 8);
-		writel(val, d->regs + DSI_DIRECT_CMD_WRDAT1);
-	}
-	if (txlen > 8) {
-		val = 0;
-		for (i = 0; i < 4 && (i + 8) < txlen; i++)
-			val |= tx[i + 8] << (i * 8);
-		writel(val, d->regs + DSI_DIRECT_CMD_WRDAT2);
-	}
-	if (txlen > 12) {
-		val = 0;
-		for (i = 0; i < 4 && (i + 12) < txlen; i++)
-			val |= tx[i + 12] << (i * 8);
-		writel(val, d->regs + DSI_DIRECT_CMD_WRDAT3);
-	}
 
 	writel(~0, d->regs + DSI_DIRECT_CMD_STS_CLR);
 	writel(~0, d->regs + DSI_CMD_MODE_STS_CLR);
@@ -283,6 +234,7 @@ static ssize_t mcde_dsi_host_transfer(struct mipi_dsi_host *host,
 			usleep_range(loop_delay_us, (loop_delay_us * 3) / 2);
 		if (!loop_counter) {
 			dev_err(d->dev, "DSI read timeout!\n");
+			/* Set exit code and retry */
 			return -ETIME;
 		}
 	} else {
@@ -293,6 +245,7 @@ static ssize_t mcde_dsi_host_transfer(struct mipi_dsi_host *host,
 			usleep_range(loop_delay_us, (loop_delay_us * 3) / 2);
 
 		if (!loop_counter) {
+			/* Set exit code and retry */
 			dev_err(d->dev, "DSI write timeout!\n");
 			return -ETIME;
 		}
@@ -334,6 +287,93 @@ static ssize_t mcde_dsi_host_transfer(struct mipi_dsi_host *host,
 		ret = rdsz;
 	}
 
+	/* Successful transmission */
+	return ret;
+}
+
+static ssize_t mcde_dsi_host_transfer(struct mipi_dsi_host *host,
+				      const struct mipi_dsi_msg *msg)
+{
+	struct mcde_dsi *d = host_to_mcde_dsi(host);
+	const u8 *tx = msg->tx_buf;
+	size_t txlen = msg->tx_len;
+	size_t rxlen = msg->rx_len;
+	unsigned int retries = 0;
+	u32 val;
+	int ret;
+	int i;
+
+	if (txlen > 16) {
+		dev_err(d->dev,
+			"dunno how to write more than 16 bytes yet\n");
+		return -EIO;
+	}
+	if (rxlen > 4) {
+		dev_err(d->dev,
+			"dunno how to read more than 4 bytes yet\n");
+		return -EIO;
+	}
+
+	dev_dbg(d->dev,
+		"message to channel %d, write %zd bytes read %zd bytes\n",
+		msg->channel, txlen, rxlen);
+
+	/* Command "nature" */
+	if (MCDE_DSI_HOST_IS_READ(msg->type))
+		/* MCTL_MAIN_DATA_CTL already set up */
+		val = DSI_DIRECT_CMD_MAIN_SETTINGS_CMD_NAT_READ;
+	else
+		val = DSI_DIRECT_CMD_MAIN_SETTINGS_CMD_NAT_WRITE;
+	/*
+	 * More than 2 bytes will not fit in a single packet, so it's
+	 * time to set the "long not short" bit. One byte is used by
+	 * the MIPI DCS command leaving just one byte for the payload
+	 * in a short package.
+	 */
+	if (mipi_dsi_packet_format_is_long(msg->type))
+		val |= DSI_DIRECT_CMD_MAIN_SETTINGS_CMD_LONGNOTSHORT;
+	val |= 0 << DSI_DIRECT_CMD_MAIN_SETTINGS_CMD_ID_SHIFT;
+	val |= txlen << DSI_DIRECT_CMD_MAIN_SETTINGS_CMD_SIZE_SHIFT;
+	val |= DSI_DIRECT_CMD_MAIN_SETTINGS_CMD_LP_EN;
+	val |= msg->type << DSI_DIRECT_CMD_MAIN_SETTINGS_CMD_HEAD_SHIFT;
+	writel(val, d->regs + DSI_DIRECT_CMD_MAIN_SETTINGS);
+
+	/* MIPI DCS command is part of the data */
+	if (txlen > 0) {
+		val = 0;
+		for (i = 0; i < 4 && i < txlen; i++)
+			val |= tx[i] << (i * 8);
+	}
+	writel(val, d->regs + DSI_DIRECT_CMD_WRDAT0);
+	if (txlen > 4) {
+		val = 0;
+		for (i = 0; i < 4 && (i + 4) < txlen; i++)
+			val |= tx[i + 4] << (i * 8);
+		writel(val, d->regs + DSI_DIRECT_CMD_WRDAT1);
+	}
+	if (txlen > 8) {
+		val = 0;
+		for (i = 0; i < 4 && (i + 8) < txlen; i++)
+			val |= tx[i + 8] << (i * 8);
+		writel(val, d->regs + DSI_DIRECT_CMD_WRDAT2);
+	}
+	if (txlen > 12) {
+		val = 0;
+		for (i = 0; i < 4 && (i + 12) < txlen; i++)
+			val |= tx[i + 12] << (i * 8);
+		writel(val, d->regs + DSI_DIRECT_CMD_WRDAT3);
+	}
+
+	while (retries < 3) {
+		ret = mcde_dsi_execute_transfer(d, msg);
+		if (ret >= 0)
+			break;
+		retries++;
+	}
+	if (ret < 0 && retries)
+		dev_err(d->dev, "gave up after %d retries\n", retries);
+
+	/* Clear any errors */
 	writel(~0, d->regs + DSI_DIRECT_CMD_STS_CLR);
 	writel(~0, d->regs + DSI_CMD_MODE_STS_CLR);
 
@@ -799,10 +839,11 @@ static void mcde_dsi_start(struct mcde_dsi *d)
 	/* Command mode, clear IF1 ID */
 	val = readl(d->regs + DSI_CMD_MODE_CTL);
 	/*
-	 * If we enable low-power mode here, with
-	 * val |= DSI_CMD_MODE_CTL_IF1_LP_EN
+	 * If we enable low-power mode here,
 	 * then display updates become really slow.
 	 */
+	if (d->mdsi->mode_flags & MIPI_DSI_MODE_LPM)
+		val |= DSI_CMD_MODE_CTL_IF1_LP_EN;
 	val &= ~DSI_CMD_MODE_CTL_IF1_ID_MASK;
 	writel(val, d->regs + DSI_CMD_MODE_CTL);
 
@@ -811,23 +852,11 @@ static void mcde_dsi_start(struct mcde_dsi *d)
 	dev_info(d->dev, "DSI link enabled\n");
 }
 
-
-static void mcde_dsi_bridge_enable(struct drm_bridge *bridge)
-{
-	struct mcde_dsi *d = bridge_to_mcde_dsi(bridge);
-	u32 val;
-
-	if (d->mdsi->mode_flags & MIPI_DSI_MODE_VIDEO) {
-		/* Enable video mode */
-		val = readl(d->regs + DSI_MCTL_MAIN_DATA_CTL);
-		val |= DSI_MCTL_MAIN_DATA_CTL_VID_EN;
-		writel(val, d->regs + DSI_MCTL_MAIN_DATA_CTL);
-	}
-
-	dev_info(d->dev, "enable DSI master\n");
-};
-
-static void mcde_dsi_bridge_pre_enable(struct drm_bridge *bridge)
+/*
+ * Notice that this is called from inside the display controller
+ * and not from the bridge callbacks.
+ */
+void mcde_dsi_enable(struct drm_bridge *bridge)
 {
 	struct mcde_dsi *d = bridge_to_mcde_dsi(bridge);
 	unsigned long hs_freq, lp_freq;
@@ -871,7 +900,25 @@ static void mcde_dsi_bridge_pre_enable(struct drm_bridge *bridge)
 		dev_info(d->dev, "DSI HS clock rate %lu Hz\n",
 			 d->hs_freq);
 
+	/* Assert RESET through the PRCMU, active low */
+	/* FIXME: which DSI block? */
+	regmap_update_bits(d->prcmu, PRCM_DSI_SW_RESET,
+			   PRCM_DSI_SW_RESET_DSI0_SW_RESETN, 0);
+
+	usleep_range(100, 200);
+
+	/* De-assert RESET again */
+	regmap_update_bits(d->prcmu, PRCM_DSI_SW_RESET,
+			   PRCM_DSI_SW_RESET_DSI0_SW_RESETN,
+			   PRCM_DSI_SW_RESET_DSI0_SW_RESETN);
+
+	/* Start up the hardware */
+	mcde_dsi_start(d);
+
 	if (d->mdsi->mode_flags & MIPI_DSI_MODE_VIDEO) {
+		/* Set up the video mode from the DRM mode */
+		mcde_dsi_setup_video_mode(d, d->mode);
+
 		/* Put IF1 into video mode */
 		val = readl(d->regs + DSI_MCTL_MAIN_DATA_CTL);
 		val |= DSI_MCTL_MAIN_DATA_CTL_IF1_MODE;
@@ -887,17 +934,25 @@ static void mcde_dsi_bridge_pre_enable(struct drm_bridge *bridge)
 		val |= DSI_VID_MODE_STS_CTL_ERR_MISSING_VSYNC;
 		val |= DSI_VID_MODE_STS_CTL_ERR_MISSING_DATA;
 		writel(val, d->regs + DSI_VID_MODE_STS_CTL);
+
+		/* Enable video mode */
+		val = readl(d->regs + DSI_MCTL_MAIN_DATA_CTL);
+		val |= DSI_MCTL_MAIN_DATA_CTL_VID_EN;
+		writel(val, d->regs + DSI_MCTL_MAIN_DATA_CTL);
 	} else {
 		/* Command mode, clear IF1 ID */
 		val = readl(d->regs + DSI_CMD_MODE_CTL);
 		/*
-		 * If we enable low-power mode here with
-		 * val |= DSI_CMD_MODE_CTL_IF1_LP_EN
+		 * If we enable low-power mode here
 		 * the display updates become really slow.
 		 */
+		if (d->mdsi->mode_flags & MIPI_DSI_MODE_LPM)
+			val |= DSI_CMD_MODE_CTL_IF1_LP_EN;
 		val &= ~DSI_CMD_MODE_CTL_IF1_ID_MASK;
 		writel(val, d->regs + DSI_CMD_MODE_CTL);
 	}
+
+	dev_info(d->dev, "enabled MCDE DSI master\n");
 }
 
 static void mcde_dsi_bridge_mode_set(struct drm_bridge *bridge,
@@ -911,13 +966,12 @@ static void mcde_dsi_bridge_mode_set(struct drm_bridge *bridge,
 		return;
 	}
 
+	d->mode = mode;
+
 	dev_info(d->dev, "set DSI master to %dx%d %u Hz %s mode\n",
 		 mode->hdisplay, mode->vdisplay, mode->clock * 1000,
 		 (d->mdsi->mode_flags & MIPI_DSI_MODE_VIDEO) ? "VIDEO" : "CMD"
 		);
-
-	if (d->mdsi->mode_flags & MIPI_DSI_MODE_VIDEO)
-		mcde_dsi_setup_video_mode(d, mode);
 }
 
 static void mcde_dsi_wait_for_command_mode_stop(struct mcde_dsi *d)
@@ -961,14 +1015,15 @@ static void mcde_dsi_wait_for_video_mode_stop(struct mcde_dsi *d)
 	}
 }
 
-static void mcde_dsi_bridge_disable(struct drm_bridge *bridge)
+/*
+ * Notice that this is called from inside the display controller
+ * and not from the bridge callbacks.
+ */
+void mcde_dsi_disable(struct drm_bridge *bridge)
 {
 	struct mcde_dsi *d = bridge_to_mcde_dsi(bridge);
 	u32 val;
 
-	/* Disable all error interrupts */
-	writel(0, d->regs + DSI_VID_MODE_STS_CTL);
-
 	if (d->mdsi->mode_flags & MIPI_DSI_MODE_VIDEO) {
 		/* Stop video mode */
 		val = readl(d->regs + DSI_MCTL_MAIN_DATA_CTL);
@@ -980,7 +1035,14 @@ static void mcde_dsi_bridge_disable(struct drm_bridge *bridge)
 		mcde_dsi_wait_for_command_mode_stop(d);
 	}
 
-	/* Stop clocks */
+	/*
+	 * Stop clocks and terminate any DSI traffic here so the panel can
+	 * send commands to shut down the display using DSI direct write until
+	 * this point.
+	 */
+
+	/* Disable all error interrupts */
+	writel(0, d->regs + DSI_VID_MODE_STS_CTL);
 	clk_disable_unprepare(d->hs_clk);
 	clk_disable_unprepare(d->lp_clk);
 }
@@ -1010,9 +1072,6 @@ static int mcde_dsi_bridge_attach(struct drm_bridge *bridge,
 static const struct drm_bridge_funcs mcde_dsi_bridge_funcs = {
 	.attach = mcde_dsi_bridge_attach,
 	.mode_set = mcde_dsi_bridge_mode_set,
-	.disable = mcde_dsi_bridge_disable,
-	.enable = mcde_dsi_bridge_enable,
-	.pre_enable = mcde_dsi_bridge_pre_enable,
 };
 
 static int mcde_dsi_bind(struct device *dev, struct device *master,
@@ -1048,21 +1107,6 @@ static int mcde_dsi_bind(struct device *dev, struct device *master,
 		return PTR_ERR(d->lp_clk);
 	}
 
-	/* Assert RESET through the PRCMU, active low */
-	/* FIXME: which DSI block? */
-	regmap_update_bits(d->prcmu, PRCM_DSI_SW_RESET,
-			   PRCM_DSI_SW_RESET_DSI0_SW_RESETN, 0);
-
-	usleep_range(100, 200);
-
-	/* De-assert RESET again */
-	regmap_update_bits(d->prcmu, PRCM_DSI_SW_RESET,
-			   PRCM_DSI_SW_RESET_DSI0_SW_RESETN,
-			   PRCM_DSI_SW_RESET_DSI0_SW_RESETN);
-
-	/* Start up the hardware */
-	mcde_dsi_start(d);
-
 	/* Look for a panel as a child to this node */
 	for_each_available_child_of_node(dev->of_node, child) {
 		panel = of_drm_find_panel(child);