[v5,0/3] drm/vkms: Introduces writeback support

Message

Rodrigo Siqueira Aug. 25, 2020, 2:31 a.m. UTC

This is the V5 version of a series that introduces the writeback support
to VKMS. The first two patches of this series are a pre-work for the
latest patch that adds the writeback connector, this patchset can be seen
in two parts: 

* A pre-work that aims to make vkms composer operations a little bit more
  generic; these patches try to centralize the vkms framebuffer operations.
* The final patch enables the support for writeback in vkms.

In the previous review, Emil suggested multiple changes in the series. I
tried to apply most of the recommendations except for some suggestions
which I was not able to incorporate due to compilation issues, or other
suggestions that may complicate this series review. I left some changes
for future patches for keeping this patchset simple with the hope of
landing this feature soon in order to support VKMS user's requirements.
Emil, let me know if you want me to change any other thing.

It is important to highlight that from the previous series to the
current version of this patchset we had some changes in the VKMS that
made it unstable.  In particular, our previous writeback series stopped
working properly due to changes in our commit tail.  Thanks to Melissa
working in the instability issue and her latest fixes to VKMS, I finally
could update writeback and make it work again. The main update in the
latest patch is the use of vkms_set_composer when the writeback work
starts (enable composer) and after the writeback end (disable composer).

Best Regard

Rodrigo Siqueira (3):
  drm/vkms: Decouple crc operations from composer
  drm/vkms: Compute CRC without change input data
  drm/vkms: Add support for writeback

 drivers/gpu/drm/vkms/Makefile         |   9 +-
 drivers/gpu/drm/vkms/vkms_composer.c  | 102 +++++++++++-------
 drivers/gpu/drm/vkms/vkms_drv.h       |  11 +-
 drivers/gpu/drm/vkms/vkms_output.c    |   4 +
 drivers/gpu/drm/vkms/vkms_writeback.c | 143 ++++++++++++++++++++++++++
 5 files changed, 231 insertions(+), 38 deletions(-)
 create mode 100644 drivers/gpu/drm/vkms/vkms_writeback.c

Comments

Melissa Wen Aug. 25, 2020, 4:02 p.m. UTC | #1

Hi Rodrigo,

Nice work!

I tested this on the kms_writeback set of subtests and works fine.

I have also checked it on the other IGT tests that I usually uses:
- kms_cursor_crc/cursor-alpha-transparent was affected by a small
  problem in the bitmap_clear of the get_pixel_from_buffer function,
  that I pointed out inline. Please, check it.
- kms_flip and kms_pipe_crc_basic works as expected (was not affected).

Best regards,

Melissa Wen

On 08/24, Rodrigo Siqueira wrote:
> This is the V5 version of a series that introduces the writeback support
> to VKMS. The first two patches of this series are a pre-work for the
> latest patch that adds the writeback connector, this patchset can be seen
> in two parts: 
> 
> * A pre-work that aims to make vkms composer operations a little bit more
>   generic; these patches try to centralize the vkms framebuffer operations.
> * The final patch enables the support for writeback in vkms.
> 
> In the previous review, Emil suggested multiple changes in the series. I
> tried to apply most of the recommendations except for some suggestions
> which I was not able to incorporate due to compilation issues, or other
> suggestions that may complicate this series review. I left some changes
> for future patches for keeping this patchset simple with the hope of
> landing this feature soon in order to support VKMS user's requirements.
> Emil, let me know if you want me to change any other thing.
> 
> It is important to highlight that from the previous series to the
> current version of this patchset we had some changes in the VKMS that
> made it unstable.  In particular, our previous writeback series stopped
> working properly due to changes in our commit tail.  Thanks to Melissa
> working in the instability issue and her latest fixes to VKMS, I finally
> could update writeback and make it work again. The main update in the
> latest patch is the use of vkms_set_composer when the writeback work
> starts (enable composer) and after the writeback end (disable composer).
> 
> Best Regard
> 
> Rodrigo Siqueira (3):
>   drm/vkms: Decouple crc operations from composer
>   drm/vkms: Compute CRC without change input data
>   drm/vkms: Add support for writeback
> 
>  drivers/gpu/drm/vkms/Makefile         |   9 +-
>  drivers/gpu/drm/vkms/vkms_composer.c  | 102 +++++++++++-------
>  drivers/gpu/drm/vkms/vkms_drv.h       |  11 +-
>  drivers/gpu/drm/vkms/vkms_output.c    |   4 +
>  drivers/gpu/drm/vkms/vkms_writeback.c | 143 ++++++++++++++++++++++++++
>  5 files changed, 231 insertions(+), 38 deletions(-)
>  create mode 100644 drivers/gpu/drm/vkms/vkms_writeback.c
> 
> -- 
> 2.28.0
>