Re: Intel SandyBridge graphics status?

[Francois Tigeot <ftigeot@xxxxxxxxxxxx>]

Hi,

On Wed, Oct 10, 2012 at 10:51:27PM +0200, Raimo Niskanen wrote:
> 
> I have a fairly modern laptop from my work that is equipped with an i5
> and thereby
> Intel SandyBridge graphics, aka Intel HD 3000.
> 
> This kind of graphics card seems to be an Achilles' heel for the BSD family,
[...]
> That video driver also requires KMS (Kernel Mode Switching) since
> it's version 2.10.
> 
> KMS seems to be the weak point, or rather the X.org driver source
> code that only talks about linux kernel versions with KMS. (Have they
> gone completely Linux:ified?!)

Sadly, yes.

> The feature appears to not be implemented in any BSD yet, or is it?

FreeBSD has apparently implemented just enough of DRM2+KMS+GEM to be able
to run the i915 kernel mode driver.
I believe OpenBSD people have also done some work to backport some of the
newest i915 KMS code (including Sandy Bridge hardware support) to the Xorg
UMS intel driver.

> DFBSD had KMS as a project in Google Summer of Code 2010 but I
> have not found out what happened with that work. Did it make it into
> the kernel sources?

Some parts did, like r600 DRM support.
David Shao keeps a "gsocdrm_github" branch on Github here
https://github.com/davshao/dflygsocdrm and merges it periodically with
-master

I gave it a try but it does nothing on my machines; it most likely only
supports old intel chipsets.
I then started to port the new FreeBSD KMS code but this work is currently
stalled for lack of time. WIP branch:
http://gitweb.dragonflybsd.org/~ftigeot/dragonfly.git/shortlog/refs/heads/fbsd_drm2

> Is there any chance for me to take the current X.org intel 2.20.9
> driver and make
> it compile in the current pkgsrc tree or will the KMS issue make this futile?

It will not work without KMS, Intel removed user-mode switching support from
the Xorg driver.

> Or should I try the same with driver version 2.9 instead? That should be before
> the hard requirement on KMS, but just might have better support than 2.7.1
> for SandyBridge. Maybe.

I _think_ 2.9 has only hw support for Arrandale but I could be wrong.
The fastest way to get something working is probably to go the OpenBSD route
and add back UMS support to the newer Xorg drivers.

-- 
Francois Tigeot