# Re: \[PATCH v3 6/9\] radeon: Switch to arch\_phys\_wc\_add and add a missing ...\_del

- From: Andy Lutomirski \<luto@amacapital.net\>
- Date: 2013-05-15 18:22:44 
- List: linux-fbdev
- Page: https://ratatoskr.run/linux-fbdev/2013/05/4049966
- Thread: https://ratatoskr.run/dri-devel/2013/05/4048815/t.md

```text
On Wed, May 15, 2013 at 7:49 AM, Jerome Glisse [ref] wrote:
> On Tue, May 14, 2013 at 5:35 PM, Andy Lutomirski [ref] wrote:
>> On Tue, May 14, 2013 at 6:37 AM, Jerome Glisse [ref] wrote:
>>> On Tue, May 14, 2013 at 8:58 AM, Alex Deucher [ref] wrote:
>>>> On Mon, May 13, 2013 at 7:58 PM, Andy Lutomirski [ref] wrote:
>>>>> 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
```