diff mbox series

drm/bridge/synopsys: dsi: read status error during transfer

Message ID 1574850193-13197-1-git-send-email-yannick.fertre@st.com (mailing list archive)
State New, archived
Headers show
Series drm/bridge/synopsys: dsi: read status error during transfer | expand

Commit Message

Yannick FERTRE Nov. 27, 2019, 10:23 a.m. UTC
From: Yannick Fertré <yannick.fertre@st.com>

Read the DSI_INT_ST1 status register to check if
errors occur while reading/writing a command to panel.
In case of error, the transfer is retried 3 times.

Signed-off-by: Yannick Fertre <yannick.fertre@st.com>
---
 drivers/gpu/drm/bridge/synopsys/dw-mipi-dsi.c | 99 +++++++++++++++++++++++----
 1 file changed, 85 insertions(+), 14 deletions(-)

Comments

Angelo Ribeiro Nov. 27, 2019, 12:07 p.m. UTC | #1
Hi Yannick,

Could you please share why you are adding this retry?
Are you trying to solve an issue with the generic interface buffs/fifos 
overflow?

I think that it could be nice read the CMD_PKT_STATUS register to ensure 
that buffs/fifos are not full or empty before a read or write.

> From: Yannick Fertre <yannick.fertre@st.com>
> Date: Wed, Nov 27, 2019 at 10:23:13
>
> From: Yannick Fertré <yannick.fertre@st.com>
> 
> Read the DSI_INT_ST1 status register to check if
> errors occur while reading/writing a command to panel.
> In case of error, the transfer is retried 3 times.
> 
> Signed-off-by: Yannick Fertre <yannick.fertre@st.com>
> ---
>  drivers/gpu/drm/bridge/synopsys/dw-mipi-dsi.c | 99 +++++++++++++++++++++++----
>  1 file changed, 85 insertions(+), 14 deletions(-)
> 
> diff --git a/drivers/gpu/drm/bridge/synopsys/dw-mipi-dsi.c b/drivers/gpu/drm/bridge/synopsys/dw-mipi-dsi.c
> index b6e793b..cc806ba 100644
> --- a/drivers/gpu/drm/bridge/synopsys/dw-mipi-dsi.c
> +++ b/drivers/gpu/drm/bridge/synopsys/dw-mipi-dsi.c
> @@ -212,6 +212,20 @@
>  
>  #define DSI_INT_ST0			0xbc
>  #define DSI_INT_ST1			0xc0
> +#define GPRXE				BIT(12)
> +#define GPRDE				BIT(11)
> +#define GPTXE				BIT(10)
> +#define GPWRE				BIT(9)
> +#define GCWRE				BIT(8)
> +#define DPIPLDWE			BIT(7)
> +#define EOTPE				BIT(6)
> +#define PSE				BIT(5)
> +#define CRCE				BIT(4)
> +#define ECCME				BIT(3)
> +#define ECCSE				BIT(2)
> +#define TOLPRX				BIT(1)
> +#define TOHSTX				BIT(0)
> +
>  #define DSI_INT_MSK0			0xc4
>  #define DSI_INT_MSK1			0xc8
>  
> @@ -397,6 +411,42 @@ static int dw_mipi_dsi_gen_pkt_hdr_write(struct dw_mipi_dsi *dsi, u32 hdr_val)
>  	return 0;
>  }
>  
> +static int dw_mipi_dsi_read_status(struct dw_mipi_dsi *dsi)
> +{
> +	u32 val;
> +
> +	val = dsi_read(dsi, DSI_INT_ST1);
> +
> +	if (val & GPRXE)
> +		DRM_DEBUG_DRIVER("DSI Generic payload receive error\n");
> +	if (val & GPRDE)
> +		DRM_DEBUG_DRIVER("DSI Generic payload read error\n");
> +	if (val & GPTXE)
> +		DRM_DEBUG_DRIVER("DSI Generic payload transmit error\n");
> +	if (val & GPWRE)
> +		DRM_DEBUG_DRIVER("DSI Generic payload write error\n");
> +	if (val & GCWRE)
> +		DRM_DEBUG_DRIVER("DSI Generic command write error\n");
> +	if (val & DPIPLDWE)
> +		DRM_DEBUG_DRIVER("DSI DPI payload write error\n");
> +	if (val & EOTPE)
> +		DRM_DEBUG_DRIVER("DSI EoTp error\n");
> +	if (val & PSE)
> +		DRM_DEBUG_DRIVER("DSI Packet size error\n");
> +	if (val & CRCE)
> +		DRM_DEBUG_DRIVER("DSI CRC error\n");
> +	if (val & ECCME)
> +		DRM_DEBUG_DRIVER("DSI ECC multi-bit error\n");
> +	if (val & ECCSE)
> +		DRM_DEBUG_DRIVER("DSI ECC single-bit error\n");
> +	if (val & TOLPRX)
> +		DRM_DEBUG_DRIVER("DSI Timeout low-power reception\n");
> +	if (val & TOHSTX)
> +		DRM_DEBUG_DRIVER("DSI Timeout high-speed transmission\n");
> +
> +	return val;
> +}
> +
>  static int dw_mipi_dsi_write(struct dw_mipi_dsi *dsi,
>  			     const struct mipi_dsi_packet *packet)
>  {
> @@ -426,6 +476,12 @@ static int dw_mipi_dsi_write(struct dw_mipi_dsi *dsi,
>  				"failed to get available write payload FIFO\n");
>  			return ret;
>  		}
> +
> +		val = dw_mipi_dsi_read_status(dsi);
> +		if (val) {
> +			dev_err(dsi->dev, "dsi status error 0x%0x\n", val);
> +			return -EINVAL;
> +		}
>  	}
>  
>  	word = 0;
> @@ -459,6 +515,12 @@ static int dw_mipi_dsi_read(struct dw_mipi_dsi *dsi,
>  			return ret;
>  		}
>  
> +		val = dw_mipi_dsi_read_status(dsi);
> +		if (val) {
> +			dev_err(dsi->dev, "dsi status error 0x%0x\n", val);
> +			return -EINVAL;
> +		}
> +
>  		val = dsi_read(dsi, DSI_GEN_PLD_DATA);
>  		for (j = 0; j < 4 && j + i < len; j++)
>  			buf[i + j] = val >> (8 * j);
> @@ -473,6 +535,7 @@ static ssize_t dw_mipi_dsi_host_transfer(struct mipi_dsi_host *host,
>  	struct dw_mipi_dsi *dsi = host_to_dsi(host);
>  	struct mipi_dsi_packet packet;
>  	int ret, nb_bytes;
> +	int retry = 3;
>  
>  	ret = mipi_dsi_create_packet(&packet, msg);
>  	if (ret) {
> @@ -484,24 +547,32 @@ static ssize_t dw_mipi_dsi_host_transfer(struct mipi_dsi_host *host,
>  	if (dsi->slave)
>  		dw_mipi_message_config(dsi->slave, msg);
>  
> -	ret = dw_mipi_dsi_write(dsi, &packet);
> -	if (ret)
> -		return ret;
> -	if (dsi->slave) {
> -		ret = dw_mipi_dsi_write(dsi->slave, &packet);
> +	while (retry--) {
> +		ret = dw_mipi_dsi_write(dsi, &packet);
>  		if (ret)
> -			return ret;
> -	}
> +			continue;
>  
> -	if (msg->rx_buf && msg->rx_len) {
> -		ret = dw_mipi_dsi_read(dsi, msg);
> -		if (ret)
> -			return ret;
> -		nb_bytes = msg->rx_len;
> -	} else {
> -		nb_bytes = packet.size;
> +		if (dsi->slave) {
> +			ret = dw_mipi_dsi_write(dsi->slave, &packet);
> +			if (ret)
> +				continue;
> +		}
> +
> +		if (msg->rx_buf && msg->rx_len) {
> +			ret = dw_mipi_dsi_read(dsi, msg);
> +			if (ret)
> +				continue;
> +			nb_bytes = msg->rx_len;
> +
> +		} else {
> +			nb_bytes = packet.size;
> +		}
> +		break;
>  	}
>  
> +	if (ret)
> +		return ret;
> +
>  	return nb_bytes;
>  }
>  
> -- 
> 2.7.4
 
Angelo Ribeiro
Software Engineer, Synopsys, Inc.
angelo.ribeiro@synopsys.com
Work: (+351)220 977 109

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diff mbox series

Patch

diff --git a/drivers/gpu/drm/bridge/synopsys/dw-mipi-dsi.c b/drivers/gpu/drm/bridge/synopsys/dw-mipi-dsi.c
index b6e793b..cc806ba 100644
--- a/drivers/gpu/drm/bridge/synopsys/dw-mipi-dsi.c
+++ b/drivers/gpu/drm/bridge/synopsys/dw-mipi-dsi.c
@@ -212,6 +212,20 @@ 
 
 #define DSI_INT_ST0			0xbc
 #define DSI_INT_ST1			0xc0
+#define GPRXE				BIT(12)
+#define GPRDE				BIT(11)
+#define GPTXE				BIT(10)
+#define GPWRE				BIT(9)
+#define GCWRE				BIT(8)
+#define DPIPLDWE			BIT(7)
+#define EOTPE				BIT(6)
+#define PSE				BIT(5)
+#define CRCE				BIT(4)
+#define ECCME				BIT(3)
+#define ECCSE				BIT(2)
+#define TOLPRX				BIT(1)
+#define TOHSTX				BIT(0)
+
 #define DSI_INT_MSK0			0xc4
 #define DSI_INT_MSK1			0xc8
 
@@ -397,6 +411,42 @@  static int dw_mipi_dsi_gen_pkt_hdr_write(struct dw_mipi_dsi *dsi, u32 hdr_val)
 	return 0;
 }
 
+static int dw_mipi_dsi_read_status(struct dw_mipi_dsi *dsi)
+{
+	u32 val;
+
+	val = dsi_read(dsi, DSI_INT_ST1);
+
+	if (val & GPRXE)
+		DRM_DEBUG_DRIVER("DSI Generic payload receive error\n");
+	if (val & GPRDE)
+		DRM_DEBUG_DRIVER("DSI Generic payload read error\n");
+	if (val & GPTXE)
+		DRM_DEBUG_DRIVER("DSI Generic payload transmit error\n");
+	if (val & GPWRE)
+		DRM_DEBUG_DRIVER("DSI Generic payload write error\n");
+	if (val & GCWRE)
+		DRM_DEBUG_DRIVER("DSI Generic command write error\n");
+	if (val & DPIPLDWE)
+		DRM_DEBUG_DRIVER("DSI DPI payload write error\n");
+	if (val & EOTPE)
+		DRM_DEBUG_DRIVER("DSI EoTp error\n");
+	if (val & PSE)
+		DRM_DEBUG_DRIVER("DSI Packet size error\n");
+	if (val & CRCE)
+		DRM_DEBUG_DRIVER("DSI CRC error\n");
+	if (val & ECCME)
+		DRM_DEBUG_DRIVER("DSI ECC multi-bit error\n");
+	if (val & ECCSE)
+		DRM_DEBUG_DRIVER("DSI ECC single-bit error\n");
+	if (val & TOLPRX)
+		DRM_DEBUG_DRIVER("DSI Timeout low-power reception\n");
+	if (val & TOHSTX)
+		DRM_DEBUG_DRIVER("DSI Timeout high-speed transmission\n");
+
+	return val;
+}
+
 static int dw_mipi_dsi_write(struct dw_mipi_dsi *dsi,
 			     const struct mipi_dsi_packet *packet)
 {
@@ -426,6 +476,12 @@  static int dw_mipi_dsi_write(struct dw_mipi_dsi *dsi,
 				"failed to get available write payload FIFO\n");
 			return ret;
 		}
+
+		val = dw_mipi_dsi_read_status(dsi);
+		if (val) {
+			dev_err(dsi->dev, "dsi status error 0x%0x\n", val);
+			return -EINVAL;
+		}
 	}
 
 	word = 0;
@@ -459,6 +515,12 @@  static int dw_mipi_dsi_read(struct dw_mipi_dsi *dsi,
 			return ret;
 		}
 
+		val = dw_mipi_dsi_read_status(dsi);
+		if (val) {
+			dev_err(dsi->dev, "dsi status error 0x%0x\n", val);
+			return -EINVAL;
+		}
+
 		val = dsi_read(dsi, DSI_GEN_PLD_DATA);
 		for (j = 0; j < 4 && j + i < len; j++)
 			buf[i + j] = val >> (8 * j);
@@ -473,6 +535,7 @@  static ssize_t dw_mipi_dsi_host_transfer(struct mipi_dsi_host *host,
 	struct dw_mipi_dsi *dsi = host_to_dsi(host);
 	struct mipi_dsi_packet packet;
 	int ret, nb_bytes;
+	int retry = 3;
 
 	ret = mipi_dsi_create_packet(&packet, msg);
 	if (ret) {
@@ -484,24 +547,32 @@  static ssize_t dw_mipi_dsi_host_transfer(struct mipi_dsi_host *host,
 	if (dsi->slave)
 		dw_mipi_message_config(dsi->slave, msg);
 
-	ret = dw_mipi_dsi_write(dsi, &packet);
-	if (ret)
-		return ret;
-	if (dsi->slave) {
-		ret = dw_mipi_dsi_write(dsi->slave, &packet);
+	while (retry--) {
+		ret = dw_mipi_dsi_write(dsi, &packet);
 		if (ret)
-			return ret;
-	}
+			continue;
 
-	if (msg->rx_buf && msg->rx_len) {
-		ret = dw_mipi_dsi_read(dsi, msg);
-		if (ret)
-			return ret;
-		nb_bytes = msg->rx_len;
-	} else {
-		nb_bytes = packet.size;
+		if (dsi->slave) {
+			ret = dw_mipi_dsi_write(dsi->slave, &packet);
+			if (ret)
+				continue;
+		}
+
+		if (msg->rx_buf && msg->rx_len) {
+			ret = dw_mipi_dsi_read(dsi, msg);
+			if (ret)
+				continue;
+			nb_bytes = msg->rx_len;
+
+		} else {
+			nb_bytes = packet.size;
+		}
+		break;
 	}
 
+	if (ret)
+		return ret;
+
 	return nb_bytes;
 }