Re: [RFC PATCH v4 0/3] Add support modifiers for drivers whose planes only support linear layout

[Andy Shevchenko]

On Tue, Jan 18, 2022 at 05:36:49PM +0900, Tomohito Esaki wrote:
> Some drivers whose planes only support linear layout fb do not support format
> modifiers.
> These drivers should support modifiers, however the DRM core should handle this
> rather than open-coding in every driver.
> 
> In this patch series, these drivers expose format modifiers based on the
> following suggestion[1].
> 
> On Thu, Nov 18, 2021 at 01:02:11PM +0000, Daniel Stone wrote:
> > I think the best way forward here is:
> >   - add a new mode_config.cannot_support_modifiers flag, and enable
> > this in radeon (plus any other drivers in the same boat)
> >   - change drm_universal_plane_init() to advertise the LINEAR modifier
> > when NULL is passed as the modifier list (including installing a
> > default .format_mod_supported hook)
> >   - remove the mode_config.allow_fb_modifiers hook and always
> > advertise modifier support, unless
> > mode_config.cannot_support_modifiers is set

FWIW,
Reviewed-by: Andy Shevchenko <andriy.shevchenko@xxxxxxxxxxxxxxx>

> [1] https://patchwork.kernel.org/project/linux-renesas-soc/patch/20190509054518.10781-1-etom@xxxxxxxxxx/#24602575
> 
> v4:
> * modify documentation for fb_modifiers_not_supported flag in kerneldoc
> 
> v3: https://www.spinics.net/lists/dri-devel/msg329102.html
> * change the order as follows:
>    1. add fb_modifiers_not_supported flag
>    2. add default modifiers
>    3. remove allow_fb_modifiers flag
> * add a conditional disable in amdgpu_dm_plane_init()
> 
> v2: https://www.spinics.net/lists/dri-devel/msg328939.html
> * rebase to the latest master branch (5.16.0+)
>       + "drm/plane: Make format_mod_supported truly optional" patch [2]
>   [2] https://patchwork.freedesktop.org/patch/467940/?series=98255&rev=3
> 
> v1: https://www.spinics.net/lists/dri-devel/msg327352.html
> * The initial patch set
> 
> Tomohito Esaki (3):
>   drm: introduce fb_modifiers_not_supported flag in mode_config
>   drm: add support modifiers for drivers whose planes only support
>     linear layout
>   drm: remove allow_fb_modifiers
> 
>  drivers/gpu/drm/amd/amdgpu/amdgpu_display.c   |  6 ++---
>  drivers/gpu/drm/amd/amdgpu/dce_v10_0.c        |  2 ++
>  drivers/gpu/drm/amd/amdgpu/dce_v11_0.c        |  2 ++
>  drivers/gpu/drm/amd/amdgpu/dce_v6_0.c         |  1 +
>  drivers/gpu/drm/amd/amdgpu/dce_v8_0.c         |  2 ++
>  .../gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c |  3 +++
>  drivers/gpu/drm/drm_framebuffer.c             |  6 ++---
>  drivers/gpu/drm/drm_ioctl.c                   |  2 +-
>  drivers/gpu/drm/drm_plane.c                   | 22 +++++++++----------
>  drivers/gpu/drm/nouveau/nouveau_display.c     |  6 +++--
>  drivers/gpu/drm/radeon/radeon_display.c       |  2 ++
>  .../gpu/drm/selftests/test-drm_framebuffer.c  |  1 -
>  include/drm/drm_mode_config.h                 | 18 +++++----------
>  include/drm/drm_plane.h                       |  3 +++
>  14 files changed, 43 insertions(+), 33 deletions(-)
> 
> -- 
> 2.25.1
> 

-- 
With Best Regards,
Andy Shevchenko