[RFC] future of drm1 in base

[Mark Johnston]

On Sat, Sep 02, 2017 at 10:02:57PM -0400, Johannes M Dieterich wrote:
> Dear current/x11,
> 
> please CC me on responses.
> 
> I am writing you on behalf of the FreeBSDDesktop team concerning the
> future of drm1 in base.
> 
> drm1 in base supports the following GPUs:
> * 3dfx Banshee/Voodoo3+ (tdfx)
> * ATI Rage 128 (r128)
> * ATI Rage Pro (mach64)
> * Matrox G200/G400 (mga)
> * Savage3D/MX/IX, Savage4, SuperSavage, Twister, ProSavage[DDR] (savage)
> * SIS 300/630/540 and XGI V3XE/V5/V8 (sis)
> * VIA Unichrome / Pro (via)
> 
> Since their original introduction up to 2010 these drivers have mostly
> been maintained as part of larger cleanups. The newest hardware drm1
> supports dates from 2004, if I am not mistaken, and most of the
> hardware is AGP-based.
> 
> With the introduction of graphics/drm-next-kmod which brings its own
> drm.ko following the Linux notation, we are facing collisions between
> these old drivers' drm.ko and the newer one.

I don't think this is a real problem. The reason one currently needs to
manually load the drm-next drm.ko (rather than just kldloading a driver
and having it pick up the right drm.ko automatically) is that our drm.ko
defines the same module ("drmn") as drm2.ko in the base system. So upon
attempting to load a drm-next driver, the kernel uses the linker hints
to load drm2.ko, which is incorrect. However, this can be addressed by
simply bumping the drmn version in the port and modifying the drivers
accordingly. I've submitted a 4-line PR which does exactly that. After
that change, we can modify the pkg-message to omit drm.ko from the
kld_list value. As a result, the name of our DRM module doesn't matter
since users don't need to specify it, so the collision with drm1 isn't a
problem.

> We would like to hear if anybody still runs CURRENT on machines housing
> the above GPUs and relies on drm1.
> 
> If there are still a significant number of people running CURRENT on
> this hardware in production, we would be willing to make a
> graphics/drm-legacy-kmod port.

With the PR I mentioned above, I think it's a non-issue to keep drm1 in
the base system. Since there appear to be at least some users of those
drivers, I really think it would be preferable to avoid removing them
unless it's absolutely necessary.