Not sure if I'm asking this in the right place. I'm n00b to the embedded linux world (and linux world in general) and I'm trying to build an embedded CLFS for a ComExpress-P2020 board. Since embedded CLFS doesn't have a book for embedded CLFS for PowerPC, I've been doing a lot trial and error and guess work. I am using linux 184.108.40.206 and U-Boot as my boot loader.
Currently I'm stumped on why it cannot mount my filesystem. I am attempting to load an ext2 compressed filesystem from ram. I used genext2fs, gzip, and then mkimage to build the ramdisk image. Here is the last bit of the console when I try to boot.
List of all partitions:
No filesystem could mount root, tried: ext2
Kernel panic - not syncing: VFS: Unable to mount root fs on unknown-block(1,0)
[ee441ee0] [c0007bd8] show_stack+0x48/0x180 (unreliable)
[ee441f20] [c026cb50] panic+0xa4/0x1e0
[ee441f70] [c02cc120] mount_block_root+0x298/0x2bc
[ee441fc0] [c02cc350] prepare_namespace+0x1a4/0x1e4
[ee441fd0] [c02cb5c8] kernel_init+0x208/0x224
[ee441ff0] [c000deac] kernel_thread+0x4c/0x68
Rebooting in 180 seconds..
I've tried using ramdisk_size, but it doesn't seem to alter anything, so I have removed it. I've also read that changing ramdisk_blocksize to 1024 would fix a similar problem, however, when I tried that, the kernel doesn't get as far and then starts spitting out garbage. Here is the bootargs I ran to get the above output.
bootargs=root=/dev/ram rw console=ttyS0,115200
From scavenging the web, it looks like this indicates that either I don't have ext2 support loaded into my kernel or I'm missing the device driver for accessing the ram. As far as I can tell, I have both enabled. I have the following kernel settings set.
My next guess would be that I'm setting up the device tree wrong... I'm building the device tree with arch/powerpc/boot/dts/p2020rdb.dts. My knowledge is very lacking on device trees...
I was also thinking maybe I botched fstab, but if it can't even load the filesystem, then I guess it wouldn't be at a point to read fstab configuration... Sigh, my knowledge is very lacking here.
I appreciate the help in advance. I will be MIA over this weekend, so I probably won't check back until Monday.