[Intel-gfx] [PATCH 2/2] drm/i915/fbdev: Setup for using FBC tracking

[Daniel Vetter]

On Wed, Aug 24, 2016 at 1:16 PM, Chris Wilson <chris at chris-wilson.co.uk> wrote:
>> > +   if (i915.enable_fbc) {
>> > +           obj->tiling_and_stride = mode_cmd.pitches[0] | I915_TILING_X;
>> > +           mode_cmd.modifier[0] = I915_FORMAT_MOD_X_TILED;
>> > +           mode_cmd.flags |= DRM_MODE_FB_MODIFIERS;
>> > +   }
>>
>> Even more magic set-tiling calls, now also depending upon module options.
>> This sounds like a rather bad idea to me.
>
> FB_MODIFIERS are pretty magic, I know!
>
> This was more of if you want to use fbdev + fbc, this is what we should
> do. Note that this is not so much a module option, but fbc state. At
> this point in fbdev's lifecycle, we should be able to use HAS_FBC()
> which is equivalent to i915.enable_fbc once we've sanitized the options.

tbh I think fbdev is not something we should care about at all, beyond
making sure that it doesn't fail. For anyone who really hates X and
wayland enough to not even run them as terminal emulators there's
kmscon. Doing something "because fbdev" is imo negative justification
;-)
-Daniel
-- 
Daniel Vetter
Software Engineer, Intel Corporation
+41 (0) 79 365 57 48 - http://blog.ffwll.ch