[PATCH v3 1/2] media: imx: csi: Disable SMFC before disabling IDMA channel

Gaël PORTAY gael.portay at collabora.com
Mon Jan 21 15:21:08 UTC 2019


Philipp,

On Mon, Jan 21, 2019 at 12:49:10PM +0100, Philipp Zabel wrote:
> Hi,
> 
> On Fri, 2019-01-18 at 17:04 -0800, Steve Longerbeam wrote:
> > Disable the SMFC before disabling the IDMA channel, instead of after,
> > in csi_idmac_unsetup().
> > 
> > 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. Stopping
> > the video data stream entering the IDMA channel before disabling the
> > channel itself appears to be a reliable fix for the hard lockup. That can
> > be done either by disabling the SMFC or the CSI before disabling the
> > channel. Disabling the SMFC before the channel is the easiest solution,
> > so do that.
> > 
> > Fixes: 4a34ec8e470cb ("[media] media: imx: Add CSI subdev driver")
> > 
> > Suggested-by: Peter Seiderer <ps.report at gmx.net>
> > Reported-by: Gaël PORTAY <gael.portay at collabora.com>
> > Signed-off-by: Steve Longerbeam <slongerbeam at gmail.com>
> 
> Gaël, could we get a Tested-by: for this as well?
>

I have not tested the v3 yet. I have planned to do it later this day for
a all night testing and report the result then.

Gael


More information about the devel mailing list