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Subject: Re: [RFC PATCH 04/19] powerpc: wii: device tree
From: Benjamin Herrenschmidt <benh@kernel.crashing.org>
To: Albert Herranz <albert_herranz@yahoo.es>
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On Thu, 2009-11-26 at 16:09 +0100, Albert Herranz wrote:

> > Are the above OHCI and EHCI "special" ? If not, there's an existing
> > binding for that sort of thing, which btw requires properties to
> > indicate the endianness of the registers and in-memory data structures
> > etc...
> > 
> 
> They are a bit special because registers are in reverse little endian format,
> must be written in 32-bit chunks, and (all things point to) they have hardware bugs.

Well.. first what is "reverse little endian" ? :-) Big endian ?

The OHCI driver today has separate flags to control register endianness
and memory based data structures endianness.

I think we also only use 32-bit reads and writes no ? So that should be
covered :-)

As for HW bugs, well, as long as we know them we can define a quirk bit
and add the necessary workarounds to the driver :-)

Do you have a patch somewhere that adds the OCHI and EHCI support btw ?
 
Cheers,
Ben.