2.6 4xx GPIO OCP driver?

Travis Sawyer tsawyer at sandburst.com
Sun Feb 27 09:31:01 EST 2005

Matt Porter wrote:
> On Fri, Feb 25, 2005 at 04:19:41PM -0500, Ralph Siemsen wrote:
>>Will that work on the 440 where the devices sit above 4GB mark?  Or must 
>>one rely on there being an existing TLB mapping to bring them into 
>>32-bit space?


mmap certainly didn't like the phys address of gpio.  Tried that.
> Ack...that's the one thing we are missing. :-/ I had forgotten
> that driver/char/mem.c  calls remap_pfn_range() directly rather
> than io_remap_page_range(). Had it called the latter, we'd be OK
> since the "bigphys" fixup could take place.  We can fix /dev/mem to
> call io_remap_page_range() when on ppc32 && 36-bit phys...other arches
> do similar tricks in that driver.

Sounds like a plan, I'd be happy to test it out.

> If everybody is happy with mmaping /dev/mem then we can go try that
> route.



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