[U-Boot-Users] mcf5272 hanging while relocating

[NZG <ngustavson@emacinc.com>]

> > The current 82 code had a lot of problems in
> > the fec, timers, and initialization area. If the 5272 code is in a
> > similar state then you may need to either use a preloader, or start with
> > the patched 5282 base and modify it up to offer similar support to the
> > 5282.
>
> Guess there's some work ahead to get the rest running when u-boot finally
> runs from RAM.
The 82 and 72 are similar in a lot of ways, you may be better off starting 
from the working 82 code.

> I did already do a diff from the EMAC release to the current release
> version 1.1.2. Did you use a CVS version of the yet unreleased version
> 1.1.3 to base your changes on?
Actually Zach started the project, and I got the code from him, but I believe 
he started with 1.1.3.

> No I did not take this part of your code where you copy a small code
> segment to the internal ram which activates the approtiate CSx or internal
> flash. I don't see a need for that. I was woundering why that's really
> needed - at least on the 5282.
When you first boot up, the processor will locate either it's external or 
internal flash at address zero, depending on it's hardware configuration.
The initialization code needs to move the flash, then jump to it.
Of course, once the flash is moved, the jump instruction will disappear if 
your running from flash, causing a trap.
The 5282 port gets around this by writing this small section of code to 
internal RAM and jumping to it first.
This way the flash can be moved without removing the next instruction.
There may be a way around this, maybe relocating the vector table first and 
using the trap to redirect the code or something,  but the situation will 
have to be handled somehow.

If you can do it without writing to the internal RAM, please share with the 
rest of the class!

thx,
NZG.