[PATCH v2 0/2] media: imx: Disable CSI immediately after last EOF

[PATCH v2 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.

History:
v2:
- Whitespace fixes
- Add Fixes: and Cc: stable@vger.kernel.org
- No functional changes.

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   |  6 +++--
 2 files changed, 21 insertions(+), 11 deletions(-)

-- 
2.17.1

[PATCH v2 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.

Fixes: 4a34ec8e470cb ("[media] media: imx: Add CSI subdev driver")

Reported-by: Gaël PORTAY <gael.portay@collabora.com>
Signed-off-by: Steve Longerbeam <slongerbeam@gmail.com>
Cc: stable@vger.kernel.org
---
Changes in v2:
- restore an empty line
- Add Fixes: and Cc: stable
---
 drivers/staging/media/imx/imx-media-csi.c | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/drivers/staging/media/imx/imx-media-csi.c b/drivers/staging/media/imx/imx-media-csi.c
index e18f58f56dfb..e0f6f88e2e70 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);
 
@@ -793,9 +795,9 @@ 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] = {
-- 
2.17.1

Re: [PATCH v2 1/2] media: imx: csi: Disable CSI immediately after last EOF

[Philipp Zabel]

On Thu, 2019-01-17 at 12:49 -0800, Steve Longerbeam 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.
>
> Fixes: 4a34ec8e470cb ("[media] media: imx: Add CSI subdev driver")
> 
> Reported-by: Gaël PORTAY <gael.portay@collabora.com>
> Signed-off-by: Steve Longerbeam <slongerbeam@gmail.com>
> Cc: stable@vger.kernel.org
> ---
> Changes in v2:
> - restore an empty line
> - Add Fixes: and Cc: stable
> ---
>  drivers/staging/media/imx/imx-media-csi.c | 6 ++++--
>  1 file changed, 4 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/staging/media/imx/imx-media-csi.c b/drivers/staging/media/imx/imx-media-csi.c
> index e18f58f56dfb..e0f6f88e2e70 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);
> +

Can you add a short comment why this call is here? Since now
csi_idmac_stop is kind of a misnomer and symmetry with csi(_idmac)_start
is broken, I think this is a bit un-obvious.

Also note that now the error path of csi_start() will now call
ipu_csi_disable() while the CSI is disabled. This happens to work
because that just calls ipu_module_disable(), which is not refcounted.

>  	devm_free_irq(priv->dev, priv->eof_irq, priv);
>  	devm_free_irq(priv->dev, priv->nfb4eof_irq, priv);
>  
> @@ -793,9 +795,9 @@ 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);

Reviewed-by: Philipp Zabel <p.zabel@pengutronix.de>

regards
Philipp

Re: [PATCH v2 1/2] media: imx: csi: Disable CSI immediately after last EOF

[Steve Longerbeam]

On 1/18/19 2:24 AM, Philipp Zabel wrote:
> On Thu, 2019-01-17 at 12:49 -0800, Steve Longerbeam 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.
>>
>> Fixes: 4a34ec8e470cb ("[media] media: imx: Add CSI subdev driver")
>>
>> Reported-by: Gaël PORTAY <gael.portay@collabora.com>
>> Signed-off-by: Steve Longerbeam <slongerbeam@gmail.com>
>> Cc: stable@vger.kernel.org
>> ---
>> Changes in v2:
>> - restore an empty line
>> - Add Fixes: and Cc: stable
>> ---
>>   drivers/staging/media/imx/imx-media-csi.c | 6 ++++--
>>   1 file changed, 4 insertions(+), 2 deletions(-)
>>
>> diff --git a/drivers/staging/media/imx/imx-media-csi.c b/drivers/staging/media/imx/imx-media-csi.c
>> index e18f58f56dfb..e0f6f88e2e70 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);
>> +
> Can you add a short comment why this call is here? Since now
> csi_idmac_stop is kind of a misnomer and symmetry with csi(_idmac)_start
> is broken, I think this is a bit un-obvious.

Yeah. I think a cleaner, more symmetric solution would be to split up 
csi_idmac_stop.

>
> Also note that now the error path of csi_start() will now call
> ipu_csi_disable() while the CSI is disabled. This happens to work
> because that just calls ipu_module_disable(), which is not refcounted.

Thanks for catching. Splitting up csi_idmac_stop will fix this. Working 
on that.

Steve

>
>>   	devm_free_irq(priv->dev, priv->eof_irq, priv);
>>   	devm_free_irq(priv->dev, priv->nfb4eof_irq, priv);
>>   
>> @@ -793,9 +795,9 @@ 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);
> Reviewed-by: Philipp Zabel <p.zabel@pengutronix.de>
>
> regards
> Philipp

Re: [PATCH v2 1/2] media: imx: csi: Disable CSI immediately after last EOF

[Steve Longerbeam]

On 1/18/19 11:01 AM, Steve Longerbeam wrote:
>
>
> On 1/18/19 2:24 AM, Philipp Zabel wrote:
>> On Thu, 2019-01-17 at 12:49 -0800, Steve Longerbeam 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.
>>>
>>> Fixes: 4a34ec8e470cb ("[media] media: imx: Add CSI subdev driver")
>>>
>>> Reported-by: Gaël PORTAY <gael.portay@collabora.com>
>>> Signed-off-by: Steve Longerbeam <slongerbeam@gmail.com>
>>> Cc: stable@vger.kernel.org
>>> ---
>>> Changes in v2:
>>> - restore an empty line
>>> - Add Fixes: and Cc: stable
>>> ---
>>>   drivers/staging/media/imx/imx-media-csi.c | 6 ++++--
>>>   1 file changed, 4 insertions(+), 2 deletions(-)
>>>
>>> diff --git a/drivers/staging/media/imx/imx-media-csi.c 
>>> b/drivers/staging/media/imx/imx-media-csi.c
>>> index e18f58f56dfb..e0f6f88e2e70 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);
>>> +
>> Can you add a short comment why this call is here? Since now
>> csi_idmac_stop is kind of a misnomer and symmetry with csi(_idmac)_start
>> is broken, I think this is a bit un-obvious.
>
> Yeah. I think a cleaner, more symmetric solution would be to split up 
> csi_idmac_stop.
>
>>
>> Also note that now the error path of csi_start() will now call
>> ipu_csi_disable() while the CSI is disabled. This happens to work
>> because that just calls ipu_module_disable(), which is not refcounted.
>
> Thanks for catching. Splitting up csi_idmac_stop will fix this. 
> Working on that.


Well turns out Peter Seiderer kindly provided a solution they have been 
using for some time on custom imx6 hardware. His solution is to disable 
the SMFC before the IDMA channel, which I have tested on the SabreAuto 
and also works. This is a much simpler change, so I will post v3 that 
does this instead.

Steve

Re: [PATCH v2 1/2] media: imx: csi: Disable CSI immediately after last EOF

[Gael PORTAY]

Steeve, all,

On 1/17/19 3:49 PM, Steve Longerbeam 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.
> 
> Fixes: 4a34ec8e470cb ("[media] media: imx: Add CSI subdev driver")
> 
> Reported-by: Gaël PORTAY <gael.portay@collabora.com>
> Signed-off-by: Steve Longerbeam <slongerbeam@gmail.com>
> Cc: stable@vger.kernel.org
> ---
> Changes in v2:
> - restore an empty line
> - Add Fixes: and Cc: stable
> ---
>   drivers/staging/media/imx/imx-media-csi.c | 6 ++++--
>   1 file changed, 4 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/staging/media/imx/imx-media-csi.c b/drivers/staging/media/imx/imx-media-csi.c
> index e18f58f56dfb..e0f6f88e2e70 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);
>   
> @@ -793,9 +795,9 @@ 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] = {
> 

Tested-by: Gaël PORTAY <gael.portay@collabora.com>

Thanks,
Gael

[PATCH v2 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.

Fixes: f0d9c8924e2c3 ("[media] media: imx: Add IC subdev drivers")

Reported-by: Gaël PORTAY <gael.portay@collabora.com>
Signed-off-by: Steve Longerbeam <slongerbeam@gmail.com>
Cc: stable@vger.kernel.org
---
Changes in v2:
- Add Fixes: and Cc: stable
---
 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 v2 2/2] media: imx: prpencvf: Disable CSI immediately after last EOF

[Gael PORTAY]

Steve, all,

On 1/17/19 3:49 PM, Steve Longerbeam wrote:
> 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.
> 
> Fixes: f0d9c8924e2c3 ("[media] media: imx: Add IC subdev drivers")
> 
> Reported-by: Gaël PORTAY <gael.portay@collabora.com>
> Signed-off-by: Steve Longerbeam <slongerbeam@gmail.com>
> Cc: stable@vger.kernel.org
> ---
> Changes in v2:
> - Add Fixes: and Cc: stable
> ---
>   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)
> 

Tested-by: Gaël PORTAY <gael.portay@collabora.com>

Thanks,
Gael