[Intel-gfx] What goes where?

[Rémi Cardona]

Le 02/02/2010 20:06, Olivier Galibert a écrit :
>   Hi all,
> 
> I'm trying to find out in all the code what is pertinent for my GM45,
> or i965 as it seems to be called driver-wise.  Forgetting gallium,
> I've still found a bunch of places.
> 
> In kernelspace:
> - drm-2.6/drivers/video/intelfb

Old framebuffer driver. Incompatible with the DRM driver and has a
tendency to break userspace bits. Don't use it.

> - drm-2.6/drivers/gpu/drm/i915

That's the main kernel driver : it manages memory (GEM) and output mode
setting (KMS). It even provides a framebuffer "driver" called inteldrmfb
to replace the old intelfb driver above.

> In userspace:
> - drm/intel

Common "glue" code to talk to the DRM driver from user space. Mostly
deals with Buffer Objects to/from the DRM driver.

> - mesa/src/mesa/drivers/dri/i965

The main mesa driver for i965. There are 2 other drivers for other Intel
chips in mesa/src/mesa/drivers/dri/ : i810 and i915.

> - mesa/src/mesa/drivers/dri/intel

IIRC, that's common code shared between the 3 mesa drivers above. It
doesn't build on its own.

> - xf86-video-intel

The DDX driver, which has 2 main responsibilities these days, slowing
down cairo with RENDER (hint hint, Chris ;) ) and being the "master"
driver that "owns" /dev/dri/card0 and synchronizes all the userspace
drivers.

> And, recently:
> - cairo/src/drm/cairo-drm-i965*
> - cairo/src/drm/cairo-drm-intel*

Those 2 are experiments by Chris Wilson to speed up cairo rendering by
making it talk to the hardware directly instead of going through RENDER.
In the long term, those 2 should disappear.

Disclaimer: I'm a distribution packager and have very little intimate
knowledge of the above drivers.

Cheers,

Rémi