[U-Boot-Users] 85xx SPD LAW setup issue?

Dan Malek dan at embeddedalley.com
Thu Nov 9 01:12:59 CET 2006

On Nov 8, 2006, at 12:16 PM, Kumar Gala wrote:

> On Nov 8, 2006, at 4:45 AM, Sam Song wrote:
>> Hi,>> I found that there is a possible LAW conflict> between SPD  
>> and 85xx default settings.>> LAWBAR0 is used for DDR whereas  
>> LAWBAR1 for> PCI1. But SPD initializes DDR LAW as LAWBAR1.>> I  
>> think it could be a setup mess, right?
> Agreed, however I do remember something about wanting to keep  
> LAWBAR0  free always to allow an external agent to do things.   
> Maybe Jon  remembers more about that than I do.

The code is confusing on this point.

LAWBAR0 is reserved for an external agent boot.
However, the code in start.S explicitly sets LAWBAR0
for this feature.  The thing called LAWBAR0 in the
board specific file is actually loaded into LAWBAR1
of the processor.  The board specific LAWBARs
defined in the init.S are actually off-by-one in their
numbering into the actual processor BARs.

We should all update our board specific init.S
files so the #defines start with LAWBAR1.  It's
just a name change to make it more clear. :-)

Once the boot over external agent is done, we
could also reclaim LAWBAR0 for more DDR space
if needed.


	-- Dan

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