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.
Thanks.
-- Dan