[PATCH 0/2] media: imx: Disable CSI immediately after last EOF

[PATCH 0/2] media: imx: Disable CSI immediately after last EOF

[Steve Longerbeam]

Disable the CSI immediately after receiving the last EOF before stream
off (and thus before disabling the IDMA channel).

This fixes a complete system hard lockup on the SabreAuto when streaming
from the ADV7180, by repeatedly sending a stream off immediately followed
by stream on:

while true; do v4l2-ctl  -d4 --stream-mmap --stream-count=3; done

Eventually this either causes the system lockup or EOF timeouts at all
subsequent stream on, until a system reset.

The lockup occurs when disabling the IDMA channel at stream off. Disabling
the CSI before disabling the IDMA channel appears to be a reliable fix for
the hard lockup.


Steve Longerbeam (2):
  media: imx: csi: Disable CSI immediately after last EOF
  media: imx: prpencvf: Disable CSI immediately after last EOF

 drivers/staging/media/imx/imx-ic-prpencvf.c | 26 ++++++++++++++-------
 drivers/staging/media/imx/imx-media-csi.c   |  7 +++---
 2 files changed, 21 insertions(+), 12 deletions(-)

-- 
2.17.1

[PATCH 1/2] media: imx: csi: Disable CSI immediately after last EOF

[Steve Longerbeam]

Disable the CSI immediately after receiving the last EOF before stream
off (and thus before disabling the IDMA channel).

This fixes a complete system hard lockup on the SabreAuto when streaming
from the ADV7180, by repeatedly sending a stream off immediately followed
by stream on:

while true; do v4l2-ctl  -d4 --stream-mmap --stream-count=3; done

Eventually this either causes the system lockup or EOF timeouts at all
subsequent stream on, until a system reset.

The lockup occurs when disabling the IDMA channel at stream off. Disabling
the CSI before disabling the IDMA channel appears to be a reliable fix for
the hard lockup.

Reported-by: Gaël PORTAY <gael.portay@collabora.com>
Signed-off-by: Steve Longerbeam <slongerbeam@gmail.com>
---
 drivers/staging/media/imx/imx-media-csi.c | 7 ++++---
 1 file changed, 4 insertions(+), 3 deletions(-)

diff --git a/drivers/staging/media/imx/imx-media-csi.c b/drivers/staging/media/imx/imx-media-csi.c
index e18f58f56dfb..9218372cb997 100644
--- a/drivers/staging/media/imx/imx-media-csi.c
+++ b/drivers/staging/media/imx/imx-media-csi.c
@@ -681,6 +681,8 @@ static void csi_idmac_stop(struct csi_priv *priv)
 	if (ret == 0)
 		v4l2_warn(&priv->sd, "wait last EOF timeout\n");
 
+	ipu_csi_disable(priv->csi);
+
 	devm_free_irq(priv->dev, priv->eof_irq, priv);
 	devm_free_irq(priv->dev, priv->nfb4eof_irq, priv);
 
@@ -793,11 +795,10 @@ static void csi_stop(struct csi_priv *priv)
 		/* stop the frame interval monitor */
 		if (priv->fim)
 			imx_media_fim_set_stream(priv->fim, NULL, false);
+	} else {
+		ipu_csi_disable(priv->csi);
 	}
-
-	ipu_csi_disable(priv->csi);
 }
-
 static const struct csi_skip_desc csi_skip[12] = {
 	{ 1, 1, 0x00 }, /* Keep all frames */
 	{ 5, 6, 0x10 }, /* Skip every sixth frame */
-- 
2.17.1

[PATCH 2/2] media: imx: prpencvf: Disable CSI immediately after last EOF

[Steve Longerbeam]

The CSI must be disabled immediately after receiving the last EOF before
stream off (and thus before disabling the IDMA channel). This can be
accomplished by moving upstream stream off to just after receiving the
last EOF completion in prp_stop(). For symmetry also move upstream
stream on to end of prp_start().

This fixes a complete system hard lockup on the SabreAuto when streaming
from the ADV7180, by repeatedly sending a stream off immediately followed
by stream on:

while true; do v4l2-ctl  -d1 --stream-mmap --stream-count=3; done

Eventually this either causes the system lockup or EOF timeouts at all
subsequent stream on, until a system reset.

The lockup occurs when disabling the IDMA channel at stream off. Disabling
the CSI before disabling the IDMA channel appears to be a reliable fix for
the hard lockup.

Reported-by: Gaël PORTAY <gael.portay@collabora.com>
Signed-off-by: Steve Longerbeam <slongerbeam@gmail.com>
---
 drivers/staging/media/imx/imx-ic-prpencvf.c | 26 ++++++++++++++-------
 1 file changed, 17 insertions(+), 9 deletions(-)

diff --git a/drivers/staging/media/imx/imx-ic-prpencvf.c b/drivers/staging/media/imx/imx-ic-prpencvf.c
index 33ada6612fee..f53cdb608528 100644
--- a/drivers/staging/media/imx/imx-ic-prpencvf.c
+++ b/drivers/staging/media/imx/imx-ic-prpencvf.c
@@ -707,12 +707,23 @@ static int prp_start(struct prp_priv *priv)
 		goto out_free_nfb4eof_irq;
 	}
 
+	/* start upstream */
+	ret = v4l2_subdev_call(priv->src_sd, video, s_stream, 1);
+	ret = (ret && ret != -ENOIOCTLCMD) ? ret : 0;
+	if (ret) {
+		v4l2_err(&ic_priv->sd,
+			 "upstream stream on failed: %d\n", ret);
+		goto out_free_eof_irq;
+	}
+
 	/* start the EOF timeout timer */
 	mod_timer(&priv->eof_timeout_timer,
 		  jiffies + msecs_to_jiffies(IMX_MEDIA_EOF_TIMEOUT));
 
 	return 0;
 
+out_free_eof_irq:
+	devm_free_irq(ic_priv->dev, priv->eof_irq, priv);
 out_free_nfb4eof_irq:
 	devm_free_irq(ic_priv->dev, priv->nfb4eof_irq, priv);
 out_unsetup:
@@ -744,6 +755,12 @@ static void prp_stop(struct prp_priv *priv)
 	if (ret == 0)
 		v4l2_warn(&ic_priv->sd, "wait last EOF timeout\n");
 
+	/* stop upstream */
+	ret = v4l2_subdev_call(priv->src_sd, video, s_stream, 0);
+	if (ret && ret != -ENOIOCTLCMD)
+		v4l2_warn(&ic_priv->sd,
+			  "upstream stream off failed: %d\n", ret);
+
 	devm_free_irq(ic_priv->dev, priv->eof_irq, priv);
 	devm_free_irq(ic_priv->dev, priv->nfb4eof_irq, priv);
 
@@ -1174,15 +1191,6 @@ static int prp_s_stream(struct v4l2_subdev *sd, int enable)
 	if (ret)
 		goto out;
 
-	/* start/stop upstream */
-	ret = v4l2_subdev_call(priv->src_sd, video, s_stream, enable);
-	ret = (ret && ret != -ENOIOCTLCMD) ? ret : 0;
-	if (ret) {
-		if (enable)
-			prp_stop(priv);
-		goto out;
-	}
-
 update_count:
 	priv->stream_count += enable ? 1 : -1;
 	if (priv->stream_count < 0)
-- 
2.17.1

Re: [PATCH 1/2] media: imx: csi: Disable CSI immediately after last EOF

[Fabio Estevam]

Hi Steve,

On Thu, Jan 17, 2019 at 6:15 PM Steve Longerbeam <slongerbeam@gmail.com> wrote:
>
> Disable the CSI immediately after receiving the last EOF before stream
> off (and thus before disabling the IDMA channel).
>
> This fixes a complete system hard lockup on the SabreAuto when streaming
> from the ADV7180, by repeatedly sending a stream off immediately followed
> by stream on:
>
> while true; do v4l2-ctl  -d4 --stream-mmap --stream-count=3; done
>
> Eventually this either causes the system lockup or EOF timeouts at all
> subsequent stream on, until a system reset.
>
> The lockup occurs when disabling the IDMA channel at stream off. Disabling
> the CSI before disabling the IDMA channel appears to be a reliable fix for
> the hard lockup.
>
> Reported-by: Gaël PORTAY <gael.portay@collabora.com>
> Signed-off-by: Steve Longerbeam <slongerbeam@gmail.com>

Thanks. Since this fixes a lockup, maybe it is worth adding a Fixes
tag and Cc stable?

> ---
>  drivers/staging/media/imx/imx-media-csi.c | 7 ++++---
>  1 file changed, 4 insertions(+), 3 deletions(-)
>
> diff --git a/drivers/staging/media/imx/imx-media-csi.c b/drivers/staging/media/imx/imx-media-csi.c
> index e18f58f56dfb..9218372cb997 100644
> --- a/drivers/staging/media/imx/imx-media-csi.c
> +++ b/drivers/staging/media/imx/imx-media-csi.c
> @@ -681,6 +681,8 @@ static void csi_idmac_stop(struct csi_priv *priv)
>         if (ret == 0)
>                 v4l2_warn(&priv->sd, "wait last EOF timeout\n");
>
> +       ipu_csi_disable(priv->csi);
> +
>         devm_free_irq(priv->dev, priv->eof_irq, priv);
>         devm_free_irq(priv->dev, priv->nfb4eof_irq, priv);
>
> @@ -793,11 +795,10 @@ static void csi_stop(struct csi_priv *priv)
>                 /* stop the frame interval monitor */
>                 if (priv->fim)
>                         imx_media_fim_set_stream(priv->fim, NULL, false);
> +       } else {
> +               ipu_csi_disable(priv->csi);
>         }
> -
> -       ipu_csi_disable(priv->csi);
>  }
> -

Unneeded line removal.

Re: [PATCH 1/2] media: imx: csi: Disable CSI immediately after last EOF

[Steve Longerbeam]

Hi Fabio, thanks for the review.

On 1/17/19 12:20 PM, Fabio Estevam wrote:
> Hi Steve,
>
> On Thu, Jan 17, 2019 at 6:15 PM Steve Longerbeam <slongerbeam@gmail.com> wrote:
>> Disable the CSI immediately after receiving the last EOF before stream
>> off (and thus before disabling the IDMA channel).
>>
>> This fixes a complete system hard lockup on the SabreAuto when streaming
>> from the ADV7180, by repeatedly sending a stream off immediately followed
>> by stream on:
>>
>> while true; do v4l2-ctl  -d4 --stream-mmap --stream-count=3; done
>>
>> Eventually this either causes the system lockup or EOF timeouts at all
>> subsequent stream on, until a system reset.
>>
>> The lockup occurs when disabling the IDMA channel at stream off. Disabling
>> the CSI before disabling the IDMA channel appears to be a reliable fix for
>> the hard lockup.
>>
>> Reported-by: Gaël PORTAY <gael.portay@collabora.com>
>> Signed-off-by: Steve Longerbeam <slongerbeam@gmail.com>
> Thanks. Since this fixes a lockup, maybe it is worth adding a Fixes
> tag and Cc stable?

Right, forgot. I will do that and resubmit.


>
>> ---
>>   drivers/staging/media/imx/imx-media-csi.c | 7 ++++---
>>   1 file changed, 4 insertions(+), 3 deletions(-)
>>
>> diff --git a/drivers/staging/media/imx/imx-media-csi.c b/drivers/staging/media/imx/imx-media-csi.c
>> index e18f58f56dfb..9218372cb997 100644
>> --- a/drivers/staging/media/imx/imx-media-csi.c
>> +++ b/drivers/staging/media/imx/imx-media-csi.c
>> @@ -681,6 +681,8 @@ static void csi_idmac_stop(struct csi_priv *priv)
>>          if (ret == 0)
>>                  v4l2_warn(&priv->sd, "wait last EOF timeout\n");
>>
>> +       ipu_csi_disable(priv->csi);
>> +
>>          devm_free_irq(priv->dev, priv->eof_irq, priv);
>>          devm_free_irq(priv->dev, priv->nfb4eof_irq, priv);
>>
>> @@ -793,11 +795,10 @@ static void csi_stop(struct csi_priv *priv)
>>                  /* stop the frame interval monitor */
>>                  if (priv->fim)
>>                          imx_media_fim_set_stream(priv->fim, NULL, false);
>> +       } else {
>> +               ipu_csi_disable(priv->csi);
>>          }
>> -
>> -       ipu_csi_disable(priv->csi);
>>   }
>> -
> Unneeded line removal.

Will fix.

Steve