[U-Boot-Users] Help, how do I decouple the reset address from the hw config word on ppc82xx

[Mark Doherty]

Thanks for the prompt Wolfgang, 

It took a little bit of time to think through the u-boot lifecycle but now
it seems quite straight forward and works very well. 

I've been able to glean quite a bit of info from past posts but there
doesn't seem any way to search the archives, do you have any suggestions?

Thx

Mark Doherty
Senior Engineer

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arca technologies
2 Trench Road
Mallusk, Belfast
Northern Ireland
BT36 4TY
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-----Original Message-----
From: Wolfgang Denk [mailto:wd at denx.de]
Sent: 14 April 2003 10:17
To: Mark Doherty
Cc: 'u-boot-users at lists.sourceforge.net'
Subject: Re: [U-Boot-Users] Help, how do I decouple the reset address
from the hw config word on ppc82xx 


In message <9901EE1E8F8BD3119109009027A1B5F596AD5B at DIGINET2> you wrote:
> > 
> > I've been attempting to build u-boot to run on an embedded planet ep8260
> > board reasonably sucessfully, however my board profile has flash
starting
> > at  0xFF000000, the reset vector is of course at 0xFFF00100. I've been

There are two errors in this sentence.

Forst, there is no fixed physcal address map. The address map of your
system is defined by whatever you program into your memory controller
registers. You don't have to map you flash at 0xFF000000;  you  could
chose  any  other address as well (but this isn't your problem here).
The second error is the "of course at 0xFFF00100".  It  could  be  at
0x100  as  well,  depending  on  the  CIP/BMS  settings in your HRCW.
(Actually 0x100 seems to be a much more "natural" setting to me).

> > scanning the code and build files looking for a reference to decouple
the
> > hardware configuration word at 0xFF00000 and the reset vector at
> > 0xFFF00100 so far with no real sucess. 

This is your third error.  You  try  to  do  something  that  is  not
necessary.  Read  the  User's  Manual about how the memory controller
works, especially how boot memory space is defined (initial  settings
of BR0[BA]).


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
He'd heard her use that sweet, innocent  tone  of  voice  before.  It
meant that, pretty soon, there was going to be trouble.
                                        - Terry Pratchett, _Truckers_