[U-Boot-Users] decoding 'program check exception trap'

[Wolfgang Denk]

In message <cfqlq9$1d9$1 at sea.gmane.org> you wrote:
> 
> I have u-boot working on a custom board based on the MV64360 with a PPC
> 750GX processor. I've set the autoboot timeout to 3 secs, with the bootcmd
> to 'go 0x40004'. I have a 'serial_getc' in main_loop so that I can transfer
> a binary to the 40004 mem. location using a PCI interface via the host
> machine.

Ummm.. what _exactly_ are you  doing?  What  has  a  "serial_getc  in
main_loop"  to  do with a PCI transfer to memory? and why do you have
to  do  such  modifications  at  all  when  all  can  be  done  using
envrionment variables?

> On timeout, u-boot tries to transfer control to the binary, but it seems
> there's some problem:

What exactly is the contents of the  memory  at  0x00040004  at  this
time? [and how can you be sure about this?]

> Also, can this be due to some caching? It should not, 'cos there shouldn't
> have been any access to this location earlier for the data at that location
> to be cached, but one possibility that I can think of right now.

If there was no access to this location  earlier,  then  how  do  you
think this location could contain executable code?

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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