From mboxrd@z Thu Jan  1 00:00:00 1970
From: Christopher Harvey <charvey@matrox.com>
Date: Wed, 29 Jun 2011 10:17:18 -0400
Subject: [U-Boot] request for some debugging hints
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On 06/29/11 08:55, Christopher Harvey wrote:
> kernel version: 2.6.38
> u-boot version: 2011.06
> 
> I've got an ARM (armv7) kernel that I can boot under QEMU without
> problems, but refuses to boot with a bootm command under u-boot.
> 
> All I see is "Uncompressing Linux... done, booting the kernel.", then
> nothing else.
> 
> I'm also hitting a bug very similar to the following with gdb, so I'm
> having a hard time figuring out exactly which lines are blocking the
> kernel.
> http://sourceware.org/ml/gdb-patches/2011-02/msg00048.html
> but that patch doesn't fix it in my case.
> 
> Basically I was hoping for some hints in case somebody here has already
> dealt with a similar problem and could provide some tips to help me
> figure out how to spend my debugging time.
> 
> I was under the impression that the second a working kernel got passed
> the "Uncompressing Linux... done, booting the kernel." point there was
> very little that could go wrong since it means the kernel was completely
> loaded into memory and the entry point was picked properly.
> 
> The kernel is a very standard kernel, and uboot is a very minimal uboot
> build with no extra soc or board initializations besides memory size.
> eg:
> lowlevel_init is blank
> reset_cpu is an infinite loop
> timers aren't used
> 
> any hints or ideas appreciated,
> Chris

Turns out I wasn't passing the machine ID or the initrd values to the r1
and r2 registers.

using a standard board_init function fixed it.

I've been learning and working on u-boot on and off for 2 weeks and
solved it literally an hour or two after asking this question. It's
amazing how often that happens.

U-Boot is working great now.

thanks,
-C