Re: PAT status?

[Terence Ripperda <tripperda@nvidia.com>]

Hi Jeff,

I unfortunately haven't had much time to look at the status of the PAT
code I had been working on. there are really 2 steps to the code:

the first is enabling and configuring the PAT registers. this then
allows a page table entry define that can be passed to traditional
interfaces, such as remap_page_range or change_page_attr. this is
pretty simple and we've been using a similar interface in our driver
for some time now.

the second part was to make sure we didn't create any cache aliasing
via duplicate mappings. this part is a bit more involved and what was
holding everything back. I've been meaning to get back to looking at
this, but really haven't had the time.

I don't know if you still want to limit the additional of the first
step, based on completion of the second step. I can try to set time
aside over the next month to try and sync up and take a look at where
we stand w/ the cachemap portion of the code. I think there where
still issues with gathering/passing in the correct attributes.

Thanks,
Terence


On Tue, Nov 29, 2005 at 05:22:37PM -0500, jgarzik@pobox.com wrote:
> 
> What's the status of PAT support?
> 
> I'm interested in that sort of stuff, for use with on-board GPUs such as 
> Intel/VIA/SiS, where system memory is used rather than offboard ram.
> 
> 	Jeff
> 
> 
>