On 19.03.2015 17:29, David Miller wrote:
From: Christian König <[email protected]>
Date: Thu, 19 Mar 2015 09:50:58 +0100
In general I would say yes, but for this particular hardware it's a
bit questionable to do so.
For radeon hardware to work correctly the CPU access to the PCIE BARs
should work even without using the specialized IO macros/functions,
otherwise mapping VRAM CPU accessible isn't really possible.
What's the background of the change? Some problems on a certain CPU
platform? or just general cleanups?
It's an _iomem_ pointer, it's not a virtual address.
Therefore it is illegal to dereference the pointer.
The value is opaque and has values that only make sense when used
with the readb() et al. interfaces.
This code is relying upon the fact that on x86 it happens to be
a virtual address, but this won't work on many other architectures.
In this case I'm perfectly fine with it and the patch is Reviewed-by:
Christian König <[email protected]>
Just wanted to make sure that you're not trying to get Radeon working on
a platform which will never really support the necessary hardware features.
Regards,
Christian.
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