Hi,
fbdev is (more or less) maintained, but it's a deprecated framework. All new Linux display drivers should be done on DRM.
What about no-mmu platforms? DRM has a big fat MMU dependency in the kconfig, is there a way to write DRM driver for such devices?
/Kamil
On 25/09/15 13:41, Kamil Lulko wrote:
Hi,
fbdev is (more or less) maintained, but it's a deprecated framework. All new Linux display drivers should be done on DRM.
What about no-mmu platforms? DRM has a big fat MMU dependency in the kconfig, is there a way to write DRM driver for such devices?
I guess not.
Then again, I don't see why DRM would have a hard dependency to MMU, if the work is done to make DRM work optionally without MMU. How much work that is, I have no idea.
Tom
On Fri, Sep 25, 2015 at 04:09:46PM +0300, Tomi Valkeinen wrote:
On 25/09/15 13:41, Kamil Lulko wrote:
Hi,
fbdev is (more or less) maintained, but it's a deprecated framework. All new Linux display drivers should be done on DRM.
What about no-mmu platforms? DRM has a big fat MMU dependency in the kconfig, is there a way to write DRM driver for such devices?
I guess not.
Then again, I don't see why DRM would have a hard dependency to MMU, if the work is done to make DRM work optionally without MMU. How much work that is, I have no idea.
We have plenty drivers in drm without hw mmu, and yeah there's probably no reason at all why the drm subsystem has a hard depency on cpu MMUs. Might be some #ifdef fallout that needs to be done, but there shouldn't be anything fundamental. Maybe the old dri1 days code has something, but that's all historical cruft anyway. -Daniel
On Fri, Sep 25, 2015 at 12:41 PM, Kamil Lulko kamil.lulko@gmail.com wrote:
fbdev is (more or less) maintained, but it's a deprecated framework. All new Linux display drivers should be done on DRM.
What about no-mmu platforms? DRM has a big fat MMU dependency in the kconfig, is there a way to write DRM driver for such devices?
That would indeed be a showstopper...
I dropped the dependency, and gave it a quick try for m68knommu. Seems like DRM currently needs pgprot_writecombine() and pte_wrprotect(). Probably that can be fixed easily.
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
dri-devel@lists.freedesktop.org
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Daniel Vetter -
Geert Uytterhoeven -
Kamil Lulko -
Tomi Valkeinen