Re: Radeon drivers on PowerPC (e500)

[Martyn Welch <martyn.welch@ge.com>]

On 18/06/14 02:48, Benjamin Herrenschmidt wrote:
> On Wed, 2014-06-18 at 11:05 +1000, Dave Airlie wrote:
>>
>> I don't think we ever ioremap GART, it should kmap GART pages, ioremap
>> should only happen for VRAM areas AFAIK,
>>
>> This isn't some 32-bit vs 36-bit BAR or something, I seem to remember BenH
>> mentioning something like that before.
>
> Yes, it's a recurring problem in the DRM with physical addresses that are
> bigger than 32-bit on 32-bit systems. There have been patches done to
> fix that but afaik never quite "completed". I can dig internally if
> I can put my hand onto something.
>
> If possible at all, can you try to configure your SoC to bring the MMIO
> space of the PCIe within the bottom 32-bit of the chip address space ?
>

I've go a hold of a U-Boot build that brings the chip up in 32-bit mode 
and modified the DTS to suit. Seemed like the easiest way to see whether 
it would work. It does. I have a Radeon E6460 showing an X display, at 
the moment using the fbdev driver. Baby steps...

> (Or use a 64-bit e5500 based chip ? :-)
>

Yeah, haven't got any of those lying around ;-)

Thanks guys,

Martyn

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