Re: [PATCH v3 6/9] radeon: Switch to arch_phys_wc_add and add a missing ..._del

On Thu, May 16, 2013 at 6:50 AM, Jerome Glisse [off-list ref] wrote:

On Wed, May 15, 2013 at 2:22 PM, Andy Lutomirski [off-list ref] wrote:

quoted

On Wed, May 15, 2013 at 7:49 AM, Jerome Glisse [off-list ref] wrote:

quoted

On Tue, May 14, 2013 at 5:35 PM, Andy Lutomirski [off-list ref] wrote:

quoted

On Tue, May 14, 2013 at 6:37 AM, Jerome Glisse [off-list ref] wrote:

quoted

On Tue, May 14, 2013 at 8:58 AM, Alex Deucher [off-list ref] wrote:

quoted

On Mon, May 13, 2013 at 7:58 PM, Andy Lutomirski [off-list ref] wrote:

quoted

Reviewed-by: Daniel Vetter <redacted>
Signed-off-by: Andy Lutomirski <luto@amacapital.net>

Reviewed-by: Alex Deucher <alexander.deucher@amd.com>

I believe it will break something but we could deal with the fallout
once it happens.

FWIW, I'm running with this code on my machine right now using the
radeon driver.  Everything seems fine.  If I build without MTRRs and
without PAT, though, graphics are slow (as expected).  So I think
everything's okay.

--Andy

I am worried on p4 where i last see issue with that notably with agp.

Do you remember any details?  It looks like PAT is enabled on Pentium
4 (i.e. famliy 0xF).

--Andy

No i don't, i think it was some pat errata on those about non real ram
address and with agp. Memory is fuzzy. I might have time in couple of
week to plug back my p4 and see how it behave.

Hmm.  I couldn't find any PAT errata related to AGP.

Is it possible that the issue was that, if there was no MTRR covering
the AGP aperture, that the mapping ended up as writeback?  If so, I
fixed that in this series.

In any case, if you see any problems, please let me know.

--Andy