[U-Boot] Debugging why my kernel won't start

Rogan Dawes
2010-08-16T07:24:48Z

Hi folks,

I'm trying to get mainline u-boot working on my DNS323 (Orion5x based).
Until I am confident in the config, I'm using a chainloaded approach,
wrapping my featureful u-boot in an image file:

$ mkimage -A arm -O u-boot -T kernel -C none -a 0x3000000 -e 0x3000000
-n "UBoot dns323" -d u-boot.bin uImage.bin

I am trying to boot the default kernel that is already flashed into the
device first. The first problem is that the DNS323 uses an incorrect
mach-type value of 526, while the registered value is 1542. See
<http://wiki.dns323.info/software:kernel>). I have modified
arch/arm/include/asm/mach-types.h to set MACH_TYPE_DNS323 to the
"correct" Dlink value, which should match what the default kernel is
expecting.

Unfortunately, all I get is:

DNS323B1> bootm FF820000
## Booting kernel from Legacy Image at ff820000 ...
Image Name: Linux-2.6.12.6-arm1
Image Type: ARM Linux Kernel Image (uncompressed)
Data Size: 1490204 Bytes = 1.4 MiB
Load Address: 00008000
Entry Point: 00008000
Verifying Checksum ... OK
Loading Kernel Image ...

and it hangs there.

That appears to be this code from cmd_bootm:

case IH_COMP_NONE:
if (load == blob_start) {
printf (" XIP %s ... ", type_name);
} else {
printf (" Loading %s ... ", type_name);
memmove_wd ((void *)load, (void *)image_start,
image_len, CHUNKSZ);
}
*load_end = load + image_len;
puts("OK\n");
break;

So, the memmove_wd never completes, it seems.

I added a debug statement at the top of memmove_wd, and got:

Moving memory from ff820040 to 00008000

Is that because the uImage header is 64 bytes?

Also, the following suggests that there may be something wrong with the
addresses that I am using:

DNS323B1> bootm FF820000 FF9A0000
## Booting kernel from Legacy Image at ff820000 ...
Image Name: Linux-2.6.12.6-arm1
Image Type: ARM Linux Kernel Image (uncompressed)
Data Size: 1490204 Bytes = 1.4 MiB
Load Address: 00008000
Entry Point: 00008000
Verifying Checksum ... OK
## Loading init Ramdisk from Legacy Image at ff9a0000 ...
Image Name: Ramdisk
Image Type: ARM Linux RAMDisk Image (gzip compressed)
Data Size: 5240600 Bytes = 5 MiB
Load Address: 00800000
Entry Point: 00800000
Verifying Checksum ... Bad Data CRC
Ramdisk image is corrupt or invalid
DNS323B1>

My chainloaded u-boot is configured in an image to load at 0x3000000,
and stay there (no relocation), if I have understood these parameters
correctly:

-a 0x3000000 -e 0x3000000

Can anyone see what I am doing wrong?

Many thanks!

Rogan