Colibri iMX6ULL: Display not working in certain reboots

Hi team,

A customer is facing an issue where in rare cases of reboot, the module doesn’t show any image with the following log messages:

[Mon Mar 30 03:15:10.171 2020] Starting kernel ...
[Mon Mar 30 03:15:10.187 2020]
[Mon Mar 30 03:15:10.187 2020] start kernel entry
[Mon Mar 30 03:15:11.859 2020] [    0.852329] mxsfb 21c8000.lcdif: mxs wait for pan flip timeout
[Mon Mar 30 03:15:11.859 2020] [    1.372331] mxsfb 21c8000.lcdif: mxs wait for pan flip timeout\

After researching a bit more, it seems this is an issue in the i.MX6ULL mxsfb driver:

Is this a known issue for us? Any help would be appreciated, it seems that it can happen in any Colibri iMX6ULL.

Thanks and kind regards,
Alvaro.

Hi again @jaski.tx , I’ve been making quite a few tests and it seems that this even happens in our default console image 2.8b6.

Can you setup the following to see if you are able to reproduce it?

Colibri iMX6ULL 512MB WB IT V1.1A
Iris / Colibri EVB (indiferent)
Console image 2.8b6.

Run the following service to automatically reboot the board on boot:

/etc/systemd/system/reboot.service

[Unit]
Description=Reboot service
After=multi-user.target
 
[Service]
Type=simple
ExecStart=/sbin/reboot         
 
[Install]
WantedBy=multi-user.target

Then simply enable and start the service:

systemctl enable reboot.service
systemctl start reboot.service

Add the following parameters to U-boot:
bootdelay is 0 and add quiet to defargs (should happen anyway but this helps make the boot faster).

Capture log with cat or grabserial. It happens a very low amount of times. Search for pan

Starting kernel ...

[    0.889236] mxsfb 21c8000.lcdif: mxs wait for pan flip timeout
[    1.399230] mxsfb 21c8000.lcdif: mxs wait for pan flip timeout
[    1.469522] gpmi-nand 1806000.gpmi-nand: mode:5 ,failed in set feature.
[   10.132417] mcp251x spi0.0: Cannot initialize MCP2515. Wrong wiring?
[   10.212335] mcp251x spi0.0: Probe failed, err=19
[   17.349825] sdio platform data not available
[   18.109517] mxsfb 21c8000.lcdif: mxs wait for pan flip timeout
[   18.921260] watchdog: watchdog0: watchdog did not stop!
[   19.786155] imx2-wdt 20bc000.wdog: Device shutdown: Expect reboot!
[   19.792950] reboot: Restarting system

Thanks, Alvaro.

A customer just asked me about this. The issue was just bad timings. Setting this to Uboot, solved the issue.

videomode video=ctfb:x:640,y:480,depth:18,pclk:39683,le:0,ri:80,up:0,lo:20,hs:80,vs:25,sync:0,vmode:0