Am Freitag, dem 12.11.2021 um 15:49 +0100 schrieb Martin Kepplinger: > > > Am 12. November 2021 13:40:43 MEZ schrieb Alexander Stein > <alexander.stein@xxxxxxxxxxxxxxx>: > > Hello Martin, > > > > Am Freitag, dem 12.11.2021 um 12:23 +0100 schrieb Martin > > Kepplinger: > > > hi Laurent and all who it may concern, > > > > > > Ever since I switches to using imx7-media-csi on imx8mq I have > > > seen a > > > bug that hangs /freezes the system so that I can't really save a > > > trace > > > or get logs for it. It happens not every time when starting > > > streaming, > > > but sometimes - when starting to stream frames. > > > > > > It kind of looks like a lock not released or something similar, > > > but > > > some race condition might happen since it's happening every 2 to > > > 10 > > > times. > > > > > > For me, when it fails, it fails the first time when starting to > > > stream > > > after rebooting. If it succeeds that first time, it continues to > > > succeed, until I reboot. > > > > When I read your description I was immediately reminded to this > > post on > > NXP forums [1]. > > I do not know if this is what is happening to you, but it sounds > > somewhat similar. There is also an errata in post [2] describing > > some > > backgrounds. Later posts also describe that apparently only CSI > > port 1 > > is affected, but CSI port 2 is not. > > Do you have the possibility to test CSI port 2? > > yes but I can only say that csi port 2 behaves better while I have > seen a lockup there too. That too matches your links' issue > description. I dont have logs from port 2 yet. > > Thanks a lot, there's at least something new to test I think. Let's > see whether a kernel thread would work instead of an m4 program. > > But why haven't I ever seen the problem on the mx6s_capture nxp > driver? That doesn't fit the picture yet for me. > > > > > Best regards, > > Alexander > > > > [1] > > https://community.nxp.com/t5/i-MX-Processors/IMX8MQ-MIPI-CSI2-Base-address-switching-change-error/m-p/1218063 > > [2] > > https://community.nxp.com/t5/i-MX-Processors/IMX8MQ-MIPI-CSI2-Base-address-switching-change-error/m-p/1216509/highlight/true#M167970 > > this seems to be fixed by https://lore.kernel.org/linux-media/20211117092710.3084034-1-martin.kepplinger@xxxxxxx/T/#t the issue described in the nxp forums should be taken care of by the underrun (or called "discard" in the nxp driver) buffer in the driver. thank you! martin