[PATCH v3 0/6] Add method to describe tile/bit_level_packed formats

[Daniel Vetter]

On Fri, Oct 05, 2018 at 09:26:43AM +0000, Alexandru-Cosmin Gheorghe wrote:
> There has been some discussion about extending drm core to handle
> linear tile formats, in the series sent by me here [1] and how to
> handle formats that are intended to be used just with
> modifiers(particularly AFBC modifiers) on Brian series [2] and on IRC
> here [3] and [4].
> 
> Hence, this big-merged series:
> 
> Patches 1-3: handle tiled formats both in core and in malidp driver,
> this is done by extending drm_format_info with three new fields
> char_per_block, block_w, block_h and consistently handle in the generic
> code paths, both linear tiled formats and normal formats.
> What's different from [1] is the interpretation of pitch for tile
> formats which has been kept to be the same as for the other formats:
> pitch = average_chars_per_pixel * width.
> 
> Patches 4-6: Introduce the YUV AFBC formats, the only thing noteworthy
> here is that cpp/char_per_block are set to 0 for formats where it's
> mandatory to be used together with a non-linear modifier and then that
> is used to bypass pitch check in framebuffer_check for formats that
> have cpp/char_per_block set to 0.
> 
> [1] https://lists.freedesktop.org/archives/dri-devel/2018-September/188245.html
> [2] https://lists.freedesktop.org/archives/dri-devel/2018-September/189620.html
> [3] https://people.freedesktop.org/~cbrill/dri-log/?channel=dri-devel&highlight_names=&date=2018-09-13&show_html=true
> [4] https://people.freedesktop.org/~cbrill/dri-log/?channel=dri-devel&highlight_names=&date=2018-09-14&show_html=true
> 
> Alexandru Gheorghe (4):
>   drm/fourcc: Add char_per_block, block_w and block_h in drm_format_info
>   drm/fourcc: Add fourcc for Mali linear tiled formats
>   drm: mali-dp: Enable Mali-DP tiled buffer formats
>   drm: Extend framebuffer_check to handle formats with
>     cpp/char_per_block 0
> 
> Brian Starkey (2):
>   drm/fourcc: Add AFBC yuv fourccs for Mali
>   drm/afbc: Add AFBC modifier usage documentation

I think at the design level we're getting there, yay! Bunch of
comments/suggestions/ideas on patch one.

It looks like the patch 7 is missing though, since the fancy formats where
you have no linear layout isn't enabled in mali-dp (afaics at least).
Depending what those look like, my suggestion to require drivers to use
->get_format_info instead might or might not work.

Cheers, Daniel

> 
>  Documentation/gpu/afbc.rst                   | 233 +++++++++++++++++++
>  Documentation/gpu/drivers.rst                |   1 +
>  MAINTAINERS                                  |   1 +
>  drivers/gpu/drm/arm/malidp_hw.c              |  14 +-
>  drivers/gpu/drm/arm/malidp_planes.c          |  23 +-
>  drivers/gpu/drm/drm_fb_cma_helper.c          |  21 +-
>  drivers/gpu/drm/drm_fb_helper.c              |   6 +
>  drivers/gpu/drm/drm_fourcc.c                 |  65 ++++++
>  drivers/gpu/drm/drm_framebuffer.c            |  13 +-
>  drivers/gpu/drm/drm_gem_framebuffer_helper.c |   4 +-
>  include/drm/drm_fourcc.h                     |  29 ++-
>  include/uapi/drm/drm_fourcc.h                |  31 +++
>  12 files changed, 428 insertions(+), 13 deletions(-)
>  create mode 100644 Documentation/gpu/afbc.rst
> 
> -- 
> 2.18.0
> 

-- 
Daniel Vetter
Software Engineer, Intel Corporation
http://blog.ffwll.ch