On Thu, Dec 8, 2016 at 11:10 AM, Daniel Vetter daniel@ffwll.ch wrote:
On Thu, Dec 08, 2016 at 12:01:19PM +1100, Benjamin Herrenschmidt wrote:
On Wed, 2016-11-23 at 10:03 +0200, Tomi Valkeinen wrote:
Since the fbdev framework is in maintenance mode and all new display drivers should be made with the DRM framework, remove the fbdev drivers from staging.
Note: the patches are created with git format-patch -D, so they can't be applied. Only for review.
I missed the discussion where this decision was made, I admit I am unimpressed by it.
DRM drivers don't strike me as suitable for small/slow cores with dumb framebuffers or simple 2D only accel, such as the one found in the ASpeed BMCs.
We have a helper for simple drivers now, if you take into account the massive helper libraries for everything that comes along with drm I expect if even dumb panels behind slow spi buses drm is now the more suitable subsytem.
This has been going on your years: 1. Fbdev is obsolete, everybody should use DRM instead! 2. Can you please point me to a small sample driver for a dumb frame buffer? 3. Several are being written, but none of them is upstream yet. 4. Goto 1.
With drmfb you basically have to shadow everything into memory & copy over everything, and locks you out of simple 2D accel. For a simple text console the result is orders of magnitude slower and memory hungry than a simple fbdev.
Not true, we have full fbdev emulation, and drivers can implement the 2d accel in there. And a bunch of them do. It's just that most teams decided that this is pointless waste of their time.j
At least that was the case last I looked at the DRM stuff with Dave, maybe things have changed...
Not everything has a powerful 3D GPU.
That's correct, and drm can cope. And compared to fbdev there's a very active community who improves&refactors it every kernel release to make it even better. Since about 2 years (when atomic landed) we merge new drivers at a rate of 2-3 per kernel release, and those new drivers get ever simpler and smaller thanks to all this work.
You mean the kind of refactoring that causes severe merge conflicts between drm-next and Linus' tree about every single day? (sorry, couldn't resist ;-)
Gr{oetje,eeting}s,
Geert
-- Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org
In personal conversations with technical people, I call myself a hacker. But when I'm talking to journalists I just say "programmer" or something like that. -- Linus Torvalds