Re: powerpc_flash_init(), wtf!?

On Thu, May 03, 2007 at 08:07:27PM +0200, Segher Boessenkool wrote:

quoted

quoted

    Yeah, you're right here, and I've probably misunderstood what 
"memory" node was. In fact, the flash in my system resides on the 
same local bus as RAM, so the proper place would be behind the "lbc" 
(or whatever -- it doesn't exist as yet) node on the "soc" bus.  Do 
you think I need to go and document it as well for such cause? :-]

   No, that probably won't do. MPC85xx SoC bus has ranges = <e0000000 
00100000> and the NOR flash is mapped at 0xff000000, so it seems that 
it can't be located under the "soc" bus (unless that latter has 
"ranges" prop extended?).

If the RAM and/or ROM sit on the SoC bus, the "ranges"
property in the SoC node should be able to translate
their addresses, yes.  You could opt for having the
memory controller a separate device node, as a sibling
of the "soc" node, if that agrees better with your
SoC architecture.  "It all depends".

But if the flash really is on an external bus controlled by a bus
controller on the SoC, it sounds like it should go under that bus
bridge.  In which case the SoC would need another range in its ranges
property.

-- 
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