device_remove error log from u-boot with i.MX8MM EVK

[cliffkong]

Hi all,

Customer is running L5.10.9 BSP from development board based on ii.M8MM. u-boot and kernel booting is okay and no issue. They report error message output from u-boot while jumping into Kernel. 

unable to select a mode
device_remove: Device 'mmc@30b60000.blk' failed to remove, but children are gone

I tested it from i.MX8MM EVK board based on same L5.10.9 and I could also see the same error message. Please refer to below log dump. Customer is cleaning up the log output and don't want to have error log from production.

how to remove this error log? and why this error happen?

U-Boot 2020.04-5.10.9-1.0.0+gad7b74b415a (Mar 05 2021 - 07:05:56 +0000)

CPU: i.MX8MMQ rev1.0 at 1200MHz
CPU: Commercial temperature grade (0C to 95C) at 41C
Reset cause: POR
Model: NXP i.MX8MM EVK board
DRAM: 2 GiB
TCPC: Vendor ID [0x1fc9], Product ID [0x5110], Addr [I2C1 0x52]
Power supply on USB2
TCPC: Vendor ID [0x1fc9], Product ID [0x5110], Addr [I2C1 0x50]
MMC: FSL_SDHC: 1, FSL_SDHC: 2
Loading Environment from MMC... OK
[*]-Video Link 0Can't find cec device id=0x3c
fail to probe panel device adv7535@3d
failed to get any video link display timings
probe video device failed, ret -22

[0] lcdif@32e00000, video
[1] mipi_dsi@32e10000, video_bridge
[2] adv7535@3d, panel
Can't find cec device id=0x3c
fail to probe panel device adv7535@3d
failed to get any video link display timings
probe video device failed, ret -22
In: serial
Out: serial
Err: serial

BuildInfo:
- ATF ba76d33
- U-Boot 2020.04-5.10.9-1.0.0+gad7b74b415a

switch to partitions #0, OK
mmc2(part 0) is current device
flash target is MMC:2
Net: eth0: ethernet@30be0000
Fastboot: Normal
Normal Boot
Hit any key to stop autoboot: 0
switch to partitions #0, OK
mmc2(part 0) is current device
29280768 bytes read in 161 ms (173.4 MiB/s)
Booting from mmc ...
46889 bytes read in 12 ms (3.7 MiB/s)
## Flattened Device Tree blob at 43000000
Booting using the fdt blob at 0x43000000
Using Device Tree in place at 0000000043000000, end 000000004300e728
Can't find cec device id=0x3c
fail to probe panel device adv7535@3d
failed to get any video link display timings
probe video device failed, ret -22

Starting kernel ...

unable to select a mode
device_remove: Device 'mmc@30b60000.blk' failed to remove, but children are gone
[ 0.000000] Booting Linux on physical CPU 0x0000000000 [0x410fd034]
[ 0.000000] Linux version 5.10.9-1.0.0+g32513c25d8c7 (oe-user@oe-host) (aarch64-poky-linux-gcc (GCC) 10.2.0, GNU ld (GNU Binutils) 2.35.0.20200730) #1 SMP PREEMPT Tue Mar

...

[cliffkong · Accepted solution]

Hi, 

Let me share my progress. Error log has been disappeared with workaround to disable "MMC_HS400_ES_SUPPORT" from u-boot config.

I see the failure log is caused by failure in setting speed mode to HS400ES. So the workaround is to deselect "MMC_HS400_ES_SUPPORT" from u-boot config. It allows to set emmc speed mode as HS400, instead of HS400ES(best mode). I still don't know why it failed in HS400ES mode although the device support it. 

Then I will close this ticket myself.

[cliffkong]

Hi Team,

Can I get any help or feedback?

Thanks,

BR/Cliff