[U-Boot-Users] Kernel hangs after decompressing.

Wolfgang Denk wd at denx.de
Fri Sep 12 16:50:37 CEST 2003

Dear David,

in message <OFEE9207A1.054F5F7A-ON85256D9F.004C558D at nanometrics.ca> you wrote:
> > This cannot work. The powerpc kernel requires load address  ==  entry
> > point = 0x0000.
> Correct me if I'm wrong, I thought the kernel can be booted from any
> location in memory, the startup code in the i386 tree can boot the kernel
> from low and high memory.  I should've been more faithful to the
> documentation.  =)

With U-boot, there is no "statup  code",  there  is  just  the  Linux
kernel  which  must  be  loaded  at  0x0000 and has an entry point at

> I set the kenrel load address back to 0x0000.  I had to move the tftp load
> address to 0x400000 so that it had enough space to decompress the kernel to
> low memory.  That was the problem I had before because by default tftp
> loads uImage to 0x100000.  But I'm back to the same problem again that as
> soon as u-boot passes control to the kernel, it hangs without spitting a
> single meaningful message to the console.

There has been a lot of reasonable advice what to do:

- attach a BDI2000 and debug the code
- print a memory dump of the log_buf area and check for kernel messages

> I really need someone to tell me what could possibly go wrong here. =)

Many things can go wrong. Inclding most simple things like  that  you
forgot to pass a console= argument setting the correct baudrate.

Best regards,

Wolfgang Denk

Software Engineering:  Embedded and Realtime Systems,  Embedded Linux
Phone: (+49)-8142-4596-87  Fax: (+49)-8142-4596-88  Email: wd at denx.de
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of fire engines, or the realization that today is the Monday which on
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