Re: [RFC PATCH 0/3] Support for Solid Fill Planes

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 





On 11/7/2022 11:37 AM, Ville Syrjälä wrote:
On Fri, Oct 28, 2022 at 03:59:49PM -0700, Jessica Zhang wrote:
Introduce and add support for COLOR_FILL and COLOR_FILL_FORMAT
properties. When the color fill value is set, and the framebuffer is set
to NULL, memory fetch will be disabled.

Thinking a bit more universally I wonder if there should be
some kind of enum property:

enum plane_pixel_source {
	FB,
	COLOR,
	LIVE_FOO,
	LIVE_BAR,
	...
}

Reviving this thread as this was the initial comment suggesting to implement pixel_source as an enum.

I think the issue with having pixel_source as an enum is how to decide what counts as a NULL commit.

Currently, setting the FB to NULL will disable the plane. So I'm guessing we will extend that logic to "if there's no pixel_source set for the plane, then it will be a NULL commit and disable the plane".

In that case, the question then becomes when to set the pixel_source to NONE. Because if we do that when setting a NULL FB (or NULL solid_fill blob), it then forces userspace to set one property before the other.

Because of that, I'm thinking of having pixel_source be represented by a bitmask instead. That way, we will simply unset the corresponding pixel_source bit when passing in a NULL FB/solid_fill blob. Then, in order to detect whether a commit is NULL or has a valid pixel source, we can just check if pixel_source == 0.

Would be interested in any feedback on this.

Thanks,

Jessica Zhang


In addition, loosen the NULL FB checks within the atomic commit callstack
to allow a NULL FB when color_fill is nonzero and add FB checks in
methods where the FB was previously assumed to be non-NULL.

Finally, have the DPU driver use drm_plane_state.color_fill and
drm_plane_state.color_fill_format instead of dpu_plane_state.color_fill,
and add extra checks in the DPU atomic commit callstack to account for a
NULL FB in cases where color_fill is set.

Some drivers support hardware that have optimizations for solid fill
planes. This series aims to expose these capabilities to userspace as
some compositors have a solid fill flag (ex. SOLID_COLOR in the Android
hardware composer HAL) that can be set by apps like the Android Gears
app.

Userspace can set the color_fill value by setting COLOR_FILL_FORMAT to a
DRM format, setting COLOR_FILL to a color fill value, and setting the
framebuffer to NULL.

Is there some real reason for the format property? Ie. why not
just do what was the plan for the crttc background color and
specify the color in full 16bpc format and just pick as many
msbs from that as the hw can use?


Jessica Zhang (3):
   drm: Introduce color fill properties for drm plane
   drm: Adjust atomic checks for solid fill color
   drm/msm/dpu: Use color_fill property for DPU planes

  drivers/gpu/drm/drm_atomic.c              | 68 ++++++++++++-----------
  drivers/gpu/drm/drm_atomic_helper.c       | 34 +++++++-----
  drivers/gpu/drm/drm_atomic_uapi.c         |  8 +++
  drivers/gpu/drm/drm_blend.c               | 38 +++++++++++++
  drivers/gpu/drm/drm_plane.c               |  8 +--
  drivers/gpu/drm/msm/disp/dpu1/dpu_crtc.c  |  7 ++-
  drivers/gpu/drm/msm/disp/dpu1/dpu_plane.c | 66 ++++++++++++++--------
  include/drm/drm_atomic_helper.h           |  5 +-
  include/drm/drm_blend.h                   |  2 +
  include/drm/drm_plane.h                   | 28 ++++++++++
  10 files changed, 188 insertions(+), 76 deletions(-)

--
2.38.0

--
Ville Syrjälä
Intel



[Index of Archives]     [Linux ARM Kernel]     [Linux ARM]     [Linux Omap]     [Fedora ARM]     [Linux for Sparc]     [IETF Annouce]     [Security]     [Bugtraq]     [Linux MIPS]     [ECOS]     [Asterisk Internet PBX]     [Linux API]

  Powered by Linux