Hi,

I rebuilt socfpga_arria10_socdk_sdmmc.dtb in ./sd_card/sdfs/ using modified files:

   arch/arm/boot/dts/socfpga_arria10_socdk_sdmmc.dts
   arch/arm/boot/dts/socfpga_arria10_socdk.dtsi

When I try booting I now get:

Are you saying it worked before and now it does not anymore? Did you make changes to the device tree?

Kernel panic - not syncing: VFS: Unable to mount root fs on unknown-block(179,2)

What is this telling me?

 

Pretty much exactly what the message is saying: the kernel cannot find the root file system to mount.

I searched online and read something about the boot command in extlinux/extlinux.conf: 'root=/dev/mmcblk0p2'?

The '2' is the problem somehow?

You found the correct item: the kernel command line parameter passed by the boot loader (presumably u-boot in your case) for the root file system partition. The partition number could be the problem if the root file system is not on partition 2. It could also be that the device is incorrect (that would be the number 0). It could also be that it is the correct device and partition but no root file system has been copied to it.

You would need to use the u-boot monitor commands to track it down.

Please bear with me here. I don't have that particular board and you only provided very little information.

:rjs

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Rudolf J Streif
CEO/CTO ibeeto
+1.855.442.3386 x700