Author Topic: Mainline kernel 4.9.20 - waiting for root device /dev/mmcblk0p3  (Read 1124 times)

Offline netfab

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Hi,

I'm trying to build and run a vanilla kernel (version 4.9.20) on a cubieboard2.
I followed the wiki to build the mainline kernel [1] and mainline u-boot [2].
When trying to boot, it hangs : the kernel does not seems to load the MMC
driver.

Here is the kernel configuration file [3] I'm using. I triple checked it, and compared
it to «make sunxi_defconfig», I don't see what did I miss. CONFIG_MMC and
CONFIG_MMC_SUNXI are built-in.

Here the full boot log [4] I get using an UART module. When connecting the
cubiedboard2 to HDMI, I'm getting an additional line at the very end (don't
know why I do not have it in the log) :
Quote
waiting for root device /dev/mmcblk0p3

Here is the content of my boot.cmd :
Code: [Select]
setenv bootargs console=tty0 console=ttyS0,115200 earlyprintk=serial,ttyS0,115200 root=/dev/mmcblk0p3 ro rootwait rootfstype=ext4 panic=10 loglevel=7
fatload mmc 0 0x46000000 zImage
fatload mmc 0 0x49000000 sun7i-a20-cubieboard2.dtb
bootz 0x46000000 - 0x49000000

If I edit and rebuild my boot.cmd, it boot fine using the legacy 3.4.113
kernel, so it is not a problem with the SD card.

Does anyone have any idea that could help me ? Thanks.

1. http://linux-sunxi.org/Mainline_Kernel_Howto
2. http://linux-sunxi.org/Mainline_U-Boot#Compile_U-Boot
3. https://gist.github.com/netfab/a451246876212a46b0af4e393f581e9c#file-kernel_config-txt
4. https://gist.github.com/netfab/a451246876212a46b0af4e393f581e9c#file-u-boot_and_kernel_log-txt

Offline rgmhtt

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Re: Mainline kernel 4.9.20 - waiting for root device /dev/mmcblk0p3
« Reply #1 on: June 13, 2017, 03:04:19 pm »
Centos7-arm is up to 4.9.13 and works well.  Don't know what changes have been made between 13 and 20.

See my howto at:

www.htt-consult.com/Centos7-armv7.html

Perhaps, you can pull the kernel from Centos 7 and work from there.


Offline rgmhtt

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Re: Mainline kernel 4.9.20 - waiting for root device /dev/mmcblk0p3
« Reply #2 on: June 15, 2017, 08:50:17 am »
Centos7-armv7hl just shipped 4.9.30-203 kernel.

I am updating my howto to sed to the new kernel on install.  If you want just the kernel rpms they are at:

http://mirror.centos.org/altarch/7/kernel/armhfp/kernel-generic/Packages/

Which is pulled in from the centos-kernels repo.


Offline netfab

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Re: Mainline kernel 4.9.20 - waiting for root device /dev/mmcblk0p3
« Reply #3 on: June 17, 2017, 12:55:20 pm »
Thank you. I will look into it as soon as I have time.