diff mbox series

drm/vkms: add module parameter to set background color

Message ID 20230406172002.124456-1-mcanal@igalia.com (mailing list archive)
State New, archived
Headers show
Series drm/vkms: add module parameter to set background color | expand

Commit Message

Maíra Canal April 6, 2023, 5:20 p.m. UTC
After commit 8ba1648567e2 ("drm: vkms: Refactor the plane composer to
accept new formats") the composition is no longer performed on top of
the primary plane, but instead on top of the CRTC, which means that
now we have a background.

This opens to the possibility of coloring the background with a
personalized color. Therefore, create a module parameter that takes a
unsigned long number as an XRGB16161616 color and set the background
color to it. That said, the composition will be performed on top of
this background color. By default, the background color is black.

Signed-off-by: Maíra Canal <mcanal@igalia.com>
---

This patch intends to add a background color property to vkms through
a module parameter. Another option would be to implement this property
by adding a new KMS property that would indicate the background color.
It would be nice to hear other opinions on what would be the best
approach.

Moreover, I wrote some IGT tests to ensure that the functionality is
working correctly [1]. The tests take the CRC of a colored primary
plane, offset the primary plane out of the screen, and take the CRC
of the colored background. The two CRC must be equal.

[1] https://gitlab.freedesktop.org/mairacanal/igt-gpu-tools/-/tree/vkms/background-color

Best Regards,
- Maíra Canal

---
 Documentation/gpu/vkms.rst           |  2 --
 drivers/gpu/drm/vkms/vkms_composer.c | 20 ++++++++++++++------
 drivers/gpu/drm/vkms/vkms_drv.c      |  6 ++++++
 drivers/gpu/drm/vkms/vkms_drv.h      |  4 ++++
 4 files changed, 24 insertions(+), 8 deletions(-)

Comments

Daniel Vetter April 6, 2023, 5:28 p.m. UTC | #1
On Thu, 6 Apr 2023 at 19:20, Maíra Canal <mcanal@igalia.com> wrote:
>
> After commit 8ba1648567e2 ("drm: vkms: Refactor the plane composer to
> accept new formats") the composition is no longer performed on top of
> the primary plane, but instead on top of the CRTC, which means that
> now we have a background.
>
> This opens to the possibility of coloring the background with a
> personalized color. Therefore, create a module parameter that takes a
> unsigned long number as an XRGB16161616 color and set the background
> color to it. That said, the composition will be performed on top of
> this background color. By default, the background color is black.
>
> Signed-off-by: Maíra Canal <mcanal@igalia.com>
> ---
>
> This patch intends to add a background color property to vkms through
> a module parameter. Another option would be to implement this property
> by adding a new KMS property that would indicate the background color.
> It would be nice to hear other opinions on what would be the best
> approach.

These patches (and I think even igts for them) have been floating
around for years. The hang-up is the userspace. Turns out all
compositors want for background is black, thus far no one has figured
out a real use-case for anything else.

Maybe some time ...

> Moreover, I wrote some IGT tests to ensure that the functionality is
> working correctly [1]. The tests take the CRC of a colored primary
> plane, offset the primary plane out of the screen, and take the CRC
> of the colored background. The two CRC must be equal.
>
> [1] https://gitlab.freedesktop.org/mairacanal/igt-gpu-tools/-/tree/vkms/background-color

I wonder whether it would be more useful to have this as a Kunit
validation test to very that the vkms composing code works correctly?
Still with the modparam and vkms_config to handle it all cleanly.
-Daniel

>
> Best Regards,
> - Maíra Canal
>
> ---
>  Documentation/gpu/vkms.rst           |  2 --
>  drivers/gpu/drm/vkms/vkms_composer.c | 20 ++++++++++++++------
>  drivers/gpu/drm/vkms/vkms_drv.c      |  6 ++++++
>  drivers/gpu/drm/vkms/vkms_drv.h      |  4 ++++
>  4 files changed, 24 insertions(+), 8 deletions(-)
>
> diff --git a/Documentation/gpu/vkms.rst b/Documentation/gpu/vkms.rst
> index 49db221c0f52..dc01689d8c76 100644
> --- a/Documentation/gpu/vkms.rst
> +++ b/Documentation/gpu/vkms.rst
> @@ -121,8 +121,6 @@ There's lots of plane features we could add support for:
>  - ARGB format on primary plane: blend the primary plane into background with
>    translucent alpha.
>
> -- Add background color KMS property[Good to get started].
> -
>  - Full alpha blending on all planes.
>
>  - Rotation, scaling.
> diff --git a/drivers/gpu/drm/vkms/vkms_composer.c b/drivers/gpu/drm/vkms/vkms_composer.c
> index 8e53fa80742b..07345faee98a 100644
> --- a/drivers/gpu/drm/vkms/vkms_composer.c
> +++ b/drivers/gpu/drm/vkms/vkms_composer.c
> @@ -79,7 +79,8 @@ static void fill_background(const struct pixel_argb_u16 *background_color,
>   * from all planes, calculates the crc32 of the output from the former step,
>   * and, if necessary, convert and store the output to the writeback buffer.
>   */
> -static void blend(struct vkms_writeback_job *wb,
> +static void blend(struct vkms_device *vkms_dev,
> +                 struct vkms_writeback_job *wb,
>                   struct vkms_crtc_state *crtc_state,
>                   u32 *crc32, struct line_buffer *stage_buffer,
>                   struct line_buffer *output_buffer, size_t row_size)
> @@ -87,7 +88,12 @@ static void blend(struct vkms_writeback_job *wb,
>         struct vkms_plane_state **plane = crtc_state->active_planes;
>         u32 n_active_planes = crtc_state->num_active_planes;
>
> -       const struct pixel_argb_u16 background_color = { .a = 0xffff };
> +       const struct pixel_argb_u16 background_color = {
> +               .a =  0xffff,
> +               .r = (*vkms_dev->config->background_color >> 32) & 0xffff,
> +               .g = (*vkms_dev->config->background_color >> 16) & 0xffff,
> +               .b = *vkms_dev->config->background_color & 0xffff,
> +       };
>
>         size_t crtc_y_limit = crtc_state->base.crtc->mode.vdisplay;
>
> @@ -139,7 +145,8 @@ static int check_iosys_map(struct vkms_crtc_state *crtc_state)
>         return 0;
>  }
>
> -static int compose_active_planes(struct vkms_writeback_job *active_wb,
> +static int compose_active_planes(struct vkms_device *vkms_dev,
> +                                struct vkms_writeback_job *active_wb,
>                                  struct vkms_crtc_state *crtc_state,
>                                  u32 *crc32)
>  {
> @@ -178,7 +185,7 @@ static int compose_active_planes(struct vkms_writeback_job *active_wb,
>                 goto free_stage_buffer;
>         }
>
> -       blend(active_wb, crtc_state, crc32, &stage_buffer,
> +       blend(vkms_dev, active_wb, crtc_state, crc32, &stage_buffer,
>               &output_buffer, line_width * pixel_size);
>
>         kvfree(output_buffer.pixels);
> @@ -205,6 +212,7 @@ void vkms_composer_worker(struct work_struct *work)
>         struct drm_crtc *crtc = crtc_state->base.crtc;
>         struct vkms_writeback_job *active_wb = crtc_state->active_writeback;
>         struct vkms_output *out = drm_crtc_to_vkms_output(crtc);
> +       struct vkms_device *vkms_dev = vkms_output_to_vkms_device(out);
>         bool crc_pending, wb_pending;
>         u64 frame_start, frame_end;
>         u32 crc32 = 0;
> @@ -228,9 +236,9 @@ void vkms_composer_worker(struct work_struct *work)
>                 return;
>
>         if (wb_pending)
> -               ret = compose_active_planes(active_wb, crtc_state, &crc32);
> +               ret = compose_active_planes(vkms_dev, active_wb, crtc_state, &crc32);
>         else
> -               ret = compose_active_planes(NULL, crtc_state, &crc32);
> +               ret = compose_active_planes(vkms_dev, NULL, crtc_state, &crc32);
>
>         if (ret)
>                 return;
> diff --git a/drivers/gpu/drm/vkms/vkms_drv.c b/drivers/gpu/drm/vkms/vkms_drv.c
> index 6d3a2d57d992..a4938dcb8c3e 100644
> --- a/drivers/gpu/drm/vkms/vkms_drv.c
> +++ b/drivers/gpu/drm/vkms/vkms_drv.c
> @@ -51,6 +51,10 @@ static bool enable_overlay;
>  module_param_named(enable_overlay, enable_overlay, bool, 0444);
>  MODULE_PARM_DESC(enable_overlay, "Enable/Disable overlay support");
>
> +static unsigned long background_color = 0x000000000000;
> +module_param_named(background_color, background_color, ulong, 0644);
> +MODULE_PARM_DESC(background_color, "Background color (0xRRRRGGGGBBBB)");
> +
>  DEFINE_DRM_GEM_FOPS(vkms_driver_fops);
>
>  static void vkms_release(struct drm_device *dev)
> @@ -99,6 +103,7 @@ static int vkms_config_show(struct seq_file *m, void *data)
>         seq_printf(m, "writeback=%d\n", vkmsdev->config->writeback);
>         seq_printf(m, "cursor=%d\n", vkmsdev->config->cursor);
>         seq_printf(m, "overlay=%d\n", vkmsdev->config->overlay);
> +       seq_printf(m, "background_color=0x%lx\n", *vkmsdev->config->background_color);
>
>         return 0;
>  }
> @@ -226,6 +231,7 @@ static int __init vkms_init(void)
>         config->cursor = enable_cursor;
>         config->writeback = enable_writeback;
>         config->overlay = enable_overlay;
> +       config->background_color = &background_color;
>
>         ret = vkms_create(config);
>         if (ret)
> diff --git a/drivers/gpu/drm/vkms/vkms_drv.h b/drivers/gpu/drm/vkms/vkms_drv.h
> index 4a248567efb2..4bc2e6a6d219 100644
> --- a/drivers/gpu/drm/vkms/vkms_drv.h
> +++ b/drivers/gpu/drm/vkms/vkms_drv.h
> @@ -113,6 +113,7 @@ struct vkms_config {
>         bool writeback;
>         bool cursor;
>         bool overlay;
> +       unsigned long *background_color;
>         /* only set when instantiated */
>         struct vkms_device *dev;
>  };
> @@ -127,6 +128,9 @@ struct vkms_device {
>  #define drm_crtc_to_vkms_output(target) \
>         container_of(target, struct vkms_output, crtc)
>
> +#define vkms_output_to_vkms_device(target) \
> +       container_of(target, struct vkms_device, output)
> +
>  #define drm_device_to_vkms_device(target) \
>         container_of(target, struct vkms_device, drm)
>
> --
> 2.39.2
>
Maíra Canal April 6, 2023, 6:06 p.m. UTC | #2
On 4/6/23 14:28, Daniel Vetter wrote:
> On Thu, 6 Apr 2023 at 19:20, Maíra Canal <mcanal@igalia.com> wrote:
>>
>> After commit 8ba1648567e2 ("drm: vkms: Refactor the plane composer to
>> accept new formats") the composition is no longer performed on top of
>> the primary plane, but instead on top of the CRTC, which means that
>> now we have a background.
>>
>> This opens to the possibility of coloring the background with a
>> personalized color. Therefore, create a module parameter that takes a
>> unsigned long number as an XRGB16161616 color and set the background
>> color to it. That said, the composition will be performed on top of
>> this background color. By default, the background color is black.
>>
>> Signed-off-by: Maíra Canal <mcanal@igalia.com>
>> ---
>>
>> This patch intends to add a background color property to vkms through
>> a module parameter. Another option would be to implement this property
>> by adding a new KMS property that would indicate the background color.
>> It would be nice to hear other opinions on what would be the best
>> approach.
> 
> These patches (and I think even igts for them) have been floating
> around for years. The hang-up is the userspace. Turns out all
> compositors want for background is black, thus far no one has figured
> out a real use-case for anything else.
> 
> Maybe some time ...
> 

But, would it be okay to add this feature as a vkms' module parameter?

>> Moreover, I wrote some IGT tests to ensure that the functionality is
>> working correctly [1]. The tests take the CRC of a colored primary
>> plane, offset the primary plane out of the screen, and take the CRC
>> of the colored background. The two CRC must be equal.
>>
>> [1] https://gitlab.freedesktop.org/mairacanal/igt-gpu-tools/-/tree/vkms/background-color
> 
> I wonder whether it would be more useful to have this as a Kunit
> validation test to very that the vkms composing code works correctly?
> Still with the modparam and vkms_config to handle it all cleanly.

Not sure if this would fit as a unit test, as the vkms composing
code basically outputs a CRC, which can be better verified by
the userspace. The output_buffer and stage_buffer are internal
variables, so it would be difficult to evaluate them with a KUnit
test.

With the IGT test, we can assure that the background composition
is being performed properly using the CRC in a negative test and
also some positive tests.

Best Regards,
- Maíra Canal

> -Daniel
> 
>>
>> Best Regards,
>> - Maíra Canal
>>
>> ---
>>   Documentation/gpu/vkms.rst           |  2 --
>>   drivers/gpu/drm/vkms/vkms_composer.c | 20 ++++++++++++++------
>>   drivers/gpu/drm/vkms/vkms_drv.c      |  6 ++++++
>>   drivers/gpu/drm/vkms/vkms_drv.h      |  4 ++++
>>   4 files changed, 24 insertions(+), 8 deletions(-)
>>
>> diff --git a/Documentation/gpu/vkms.rst b/Documentation/gpu/vkms.rst
>> index 49db221c0f52..dc01689d8c76 100644
>> --- a/Documentation/gpu/vkms.rst
>> +++ b/Documentation/gpu/vkms.rst
>> @@ -121,8 +121,6 @@ There's lots of plane features we could add support for:
>>   - ARGB format on primary plane: blend the primary plane into background with
>>     translucent alpha.
>>
>> -- Add background color KMS property[Good to get started].
>> -
>>   - Full alpha blending on all planes.
>>
>>   - Rotation, scaling.
>> diff --git a/drivers/gpu/drm/vkms/vkms_composer.c b/drivers/gpu/drm/vkms/vkms_composer.c
>> index 8e53fa80742b..07345faee98a 100644
>> --- a/drivers/gpu/drm/vkms/vkms_composer.c
>> +++ b/drivers/gpu/drm/vkms/vkms_composer.c
>> @@ -79,7 +79,8 @@ static void fill_background(const struct pixel_argb_u16 *background_color,
>>    * from all planes, calculates the crc32 of the output from the former step,
>>    * and, if necessary, convert and store the output to the writeback buffer.
>>    */
>> -static void blend(struct vkms_writeback_job *wb,
>> +static void blend(struct vkms_device *vkms_dev,
>> +                 struct vkms_writeback_job *wb,
>>                    struct vkms_crtc_state *crtc_state,
>>                    u32 *crc32, struct line_buffer *stage_buffer,
>>                    struct line_buffer *output_buffer, size_t row_size)
>> @@ -87,7 +88,12 @@ static void blend(struct vkms_writeback_job *wb,
>>          struct vkms_plane_state **plane = crtc_state->active_planes;
>>          u32 n_active_planes = crtc_state->num_active_planes;
>>
>> -       const struct pixel_argb_u16 background_color = { .a = 0xffff };
>> +       const struct pixel_argb_u16 background_color = {
>> +               .a =  0xffff,
>> +               .r = (*vkms_dev->config->background_color >> 32) & 0xffff,
>> +               .g = (*vkms_dev->config->background_color >> 16) & 0xffff,
>> +               .b = *vkms_dev->config->background_color & 0xffff,
>> +       };
>>
>>          size_t crtc_y_limit = crtc_state->base.crtc->mode.vdisplay;
>>
>> @@ -139,7 +145,8 @@ static int check_iosys_map(struct vkms_crtc_state *crtc_state)
>>          return 0;
>>   }
>>
>> -static int compose_active_planes(struct vkms_writeback_job *active_wb,
>> +static int compose_active_planes(struct vkms_device *vkms_dev,
>> +                                struct vkms_writeback_job *active_wb,
>>                                   struct vkms_crtc_state *crtc_state,
>>                                   u32 *crc32)
>>   {
>> @@ -178,7 +185,7 @@ static int compose_active_planes(struct vkms_writeback_job *active_wb,
>>                  goto free_stage_buffer;
>>          }
>>
>> -       blend(active_wb, crtc_state, crc32, &stage_buffer,
>> +       blend(vkms_dev, active_wb, crtc_state, crc32, &stage_buffer,
>>                &output_buffer, line_width * pixel_size);
>>
>>          kvfree(output_buffer.pixels);
>> @@ -205,6 +212,7 @@ void vkms_composer_worker(struct work_struct *work)
>>          struct drm_crtc *crtc = crtc_state->base.crtc;
>>          struct vkms_writeback_job *active_wb = crtc_state->active_writeback;
>>          struct vkms_output *out = drm_crtc_to_vkms_output(crtc);
>> +       struct vkms_device *vkms_dev = vkms_output_to_vkms_device(out);
>>          bool crc_pending, wb_pending;
>>          u64 frame_start, frame_end;
>>          u32 crc32 = 0;
>> @@ -228,9 +236,9 @@ void vkms_composer_worker(struct work_struct *work)
>>                  return;
>>
>>          if (wb_pending)
>> -               ret = compose_active_planes(active_wb, crtc_state, &crc32);
>> +               ret = compose_active_planes(vkms_dev, active_wb, crtc_state, &crc32);
>>          else
>> -               ret = compose_active_planes(NULL, crtc_state, &crc32);
>> +               ret = compose_active_planes(vkms_dev, NULL, crtc_state, &crc32);
>>
>>          if (ret)
>>                  return;
>> diff --git a/drivers/gpu/drm/vkms/vkms_drv.c b/drivers/gpu/drm/vkms/vkms_drv.c
>> index 6d3a2d57d992..a4938dcb8c3e 100644
>> --- a/drivers/gpu/drm/vkms/vkms_drv.c
>> +++ b/drivers/gpu/drm/vkms/vkms_drv.c
>> @@ -51,6 +51,10 @@ static bool enable_overlay;
>>   module_param_named(enable_overlay, enable_overlay, bool, 0444);
>>   MODULE_PARM_DESC(enable_overlay, "Enable/Disable overlay support");
>>
>> +static unsigned long background_color = 0x000000000000;
>> +module_param_named(background_color, background_color, ulong, 0644);
>> +MODULE_PARM_DESC(background_color, "Background color (0xRRRRGGGGBBBB)");
>> +
>>   DEFINE_DRM_GEM_FOPS(vkms_driver_fops);
>>
>>   static void vkms_release(struct drm_device *dev)
>> @@ -99,6 +103,7 @@ static int vkms_config_show(struct seq_file *m, void *data)
>>          seq_printf(m, "writeback=%d\n", vkmsdev->config->writeback);
>>          seq_printf(m, "cursor=%d\n", vkmsdev->config->cursor);
>>          seq_printf(m, "overlay=%d\n", vkmsdev->config->overlay);
>> +       seq_printf(m, "background_color=0x%lx\n", *vkmsdev->config->background_color);
>>
>>          return 0;
>>   }
>> @@ -226,6 +231,7 @@ static int __init vkms_init(void)
>>          config->cursor = enable_cursor;
>>          config->writeback = enable_writeback;
>>          config->overlay = enable_overlay;
>> +       config->background_color = &background_color;
>>
>>          ret = vkms_create(config);
>>          if (ret)
>> diff --git a/drivers/gpu/drm/vkms/vkms_drv.h b/drivers/gpu/drm/vkms/vkms_drv.h
>> index 4a248567efb2..4bc2e6a6d219 100644
>> --- a/drivers/gpu/drm/vkms/vkms_drv.h
>> +++ b/drivers/gpu/drm/vkms/vkms_drv.h
>> @@ -113,6 +113,7 @@ struct vkms_config {
>>          bool writeback;
>>          bool cursor;
>>          bool overlay;
>> +       unsigned long *background_color;
>>          /* only set when instantiated */
>>          struct vkms_device *dev;
>>   };
>> @@ -127,6 +128,9 @@ struct vkms_device {
>>   #define drm_crtc_to_vkms_output(target) \
>>          container_of(target, struct vkms_output, crtc)
>>
>> +#define vkms_output_to_vkms_device(target) \
>> +       container_of(target, struct vkms_device, output)
>> +
>>   #define drm_device_to_vkms_device(target) \
>>          container_of(target, struct vkms_device, drm)
>>
>> --
>> 2.39.2
>>
> 
>
Daniel Vetter April 6, 2023, 6:23 p.m. UTC | #3
On Thu, Apr 06, 2023 at 03:06:56PM -0300, Maíra Canal wrote:
> On 4/6/23 14:28, Daniel Vetter wrote:
> > On Thu, 6 Apr 2023 at 19:20, Maíra Canal <mcanal@igalia.com> wrote:
> > > 
> > > After commit 8ba1648567e2 ("drm: vkms: Refactor the plane composer to
> > > accept new formats") the composition is no longer performed on top of
> > > the primary plane, but instead on top of the CRTC, which means that
> > > now we have a background.
> > > 
> > > This opens to the possibility of coloring the background with a
> > > personalized color. Therefore, create a module parameter that takes a
> > > unsigned long number as an XRGB16161616 color and set the background
> > > color to it. That said, the composition will be performed on top of
> > > this background color. By default, the background color is black.
> > > 
> > > Signed-off-by: Maíra Canal <mcanal@igalia.com>
> > > ---
> > > 
> > > This patch intends to add a background color property to vkms through
> > > a module parameter. Another option would be to implement this property
> > > by adding a new KMS property that would indicate the background color.
> > > It would be nice to hear other opinions on what would be the best
> > > approach.
> > 
> > These patches (and I think even igts for them) have been floating
> > around for years. The hang-up is the userspace. Turns out all
> > compositors want for background is black, thus far no one has figured
> > out a real use-case for anything else.
> > 
> > Maybe some time ...
> > 
> 
> But, would it be okay to add this feature as a vkms' module parameter?

Yeah I think that's ok.

> > > Moreover, I wrote some IGT tests to ensure that the functionality is
> > > working correctly [1]. The tests take the CRC of a colored primary
> > > plane, offset the primary plane out of the screen, and take the CRC
> > > of the colored background. The two CRC must be equal.
> > > 
> > > [1] https://gitlab.freedesktop.org/mairacanal/igt-gpu-tools/-/tree/vkms/background-color
> > 
> > I wonder whether it would be more useful to have this as a Kunit
> > validation test to very that the vkms composing code works correctly?
> > Still with the modparam and vkms_config to handle it all cleanly.
> 
> Not sure if this would fit as a unit test, as the vkms composing
> code basically outputs a CRC, which can be better verified by
> the userspace. The output_buffer and stage_buffer are internal
> variables, so it would be difficult to evaluate them with a KUnit
> test.
> 
> With the IGT test, we can assure that the background composition
> is being performed properly using the CRC in a negative test and
> also some positive tests.

I was just thinking of how you could keep the test, because igt is for
uapi in general. So doesn't fit all that well, validating internals is
more what kunit is supposed to do.
-Daniel

> 
> Best Regards,
> - Maíra Canal
> 
> > -Daniel
> > 
> > > 
> > > Best Regards,
> > > - Maíra Canal
> > > 
> > > ---
> > >   Documentation/gpu/vkms.rst           |  2 --
> > >   drivers/gpu/drm/vkms/vkms_composer.c | 20 ++++++++++++++------
> > >   drivers/gpu/drm/vkms/vkms_drv.c      |  6 ++++++
> > >   drivers/gpu/drm/vkms/vkms_drv.h      |  4 ++++
> > >   4 files changed, 24 insertions(+), 8 deletions(-)
> > > 
> > > diff --git a/Documentation/gpu/vkms.rst b/Documentation/gpu/vkms.rst
> > > index 49db221c0f52..dc01689d8c76 100644
> > > --- a/Documentation/gpu/vkms.rst
> > > +++ b/Documentation/gpu/vkms.rst
> > > @@ -121,8 +121,6 @@ There's lots of plane features we could add support for:
> > >   - ARGB format on primary plane: blend the primary plane into background with
> > >     translucent alpha.
> > > 
> > > -- Add background color KMS property[Good to get started].
> > > -
> > >   - Full alpha blending on all planes.
> > > 
> > >   - Rotation, scaling.
> > > diff --git a/drivers/gpu/drm/vkms/vkms_composer.c b/drivers/gpu/drm/vkms/vkms_composer.c
> > > index 8e53fa80742b..07345faee98a 100644
> > > --- a/drivers/gpu/drm/vkms/vkms_composer.c
> > > +++ b/drivers/gpu/drm/vkms/vkms_composer.c
> > > @@ -79,7 +79,8 @@ static void fill_background(const struct pixel_argb_u16 *background_color,
> > >    * from all planes, calculates the crc32 of the output from the former step,
> > >    * and, if necessary, convert and store the output to the writeback buffer.
> > >    */
> > > -static void blend(struct vkms_writeback_job *wb,
> > > +static void blend(struct vkms_device *vkms_dev,
> > > +                 struct vkms_writeback_job *wb,
> > >                    struct vkms_crtc_state *crtc_state,
> > >                    u32 *crc32, struct line_buffer *stage_buffer,
> > >                    struct line_buffer *output_buffer, size_t row_size)
> > > @@ -87,7 +88,12 @@ static void blend(struct vkms_writeback_job *wb,
> > >          struct vkms_plane_state **plane = crtc_state->active_planes;
> > >          u32 n_active_planes = crtc_state->num_active_planes;
> > > 
> > > -       const struct pixel_argb_u16 background_color = { .a = 0xffff };
> > > +       const struct pixel_argb_u16 background_color = {
> > > +               .a =  0xffff,
> > > +               .r = (*vkms_dev->config->background_color >> 32) & 0xffff,
> > > +               .g = (*vkms_dev->config->background_color >> 16) & 0xffff,
> > > +               .b = *vkms_dev->config->background_color & 0xffff,
> > > +       };
> > > 
> > >          size_t crtc_y_limit = crtc_state->base.crtc->mode.vdisplay;
> > > 
> > > @@ -139,7 +145,8 @@ static int check_iosys_map(struct vkms_crtc_state *crtc_state)
> > >          return 0;
> > >   }
> > > 
> > > -static int compose_active_planes(struct vkms_writeback_job *active_wb,
> > > +static int compose_active_planes(struct vkms_device *vkms_dev,
> > > +                                struct vkms_writeback_job *active_wb,
> > >                                   struct vkms_crtc_state *crtc_state,
> > >                                   u32 *crc32)
> > >   {
> > > @@ -178,7 +185,7 @@ static int compose_active_planes(struct vkms_writeback_job *active_wb,
> > >                  goto free_stage_buffer;
> > >          }
> > > 
> > > -       blend(active_wb, crtc_state, crc32, &stage_buffer,
> > > +       blend(vkms_dev, active_wb, crtc_state, crc32, &stage_buffer,
> > >                &output_buffer, line_width * pixel_size);
> > > 
> > >          kvfree(output_buffer.pixels);
> > > @@ -205,6 +212,7 @@ void vkms_composer_worker(struct work_struct *work)
> > >          struct drm_crtc *crtc = crtc_state->base.crtc;
> > >          struct vkms_writeback_job *active_wb = crtc_state->active_writeback;
> > >          struct vkms_output *out = drm_crtc_to_vkms_output(crtc);
> > > +       struct vkms_device *vkms_dev = vkms_output_to_vkms_device(out);
> > >          bool crc_pending, wb_pending;
> > >          u64 frame_start, frame_end;
> > >          u32 crc32 = 0;
> > > @@ -228,9 +236,9 @@ void vkms_composer_worker(struct work_struct *work)
> > >                  return;
> > > 
> > >          if (wb_pending)
> > > -               ret = compose_active_planes(active_wb, crtc_state, &crc32);
> > > +               ret = compose_active_planes(vkms_dev, active_wb, crtc_state, &crc32);
> > >          else
> > > -               ret = compose_active_planes(NULL, crtc_state, &crc32);
> > > +               ret = compose_active_planes(vkms_dev, NULL, crtc_state, &crc32);
> > > 
> > >          if (ret)
> > >                  return;
> > > diff --git a/drivers/gpu/drm/vkms/vkms_drv.c b/drivers/gpu/drm/vkms/vkms_drv.c
> > > index 6d3a2d57d992..a4938dcb8c3e 100644
> > > --- a/drivers/gpu/drm/vkms/vkms_drv.c
> > > +++ b/drivers/gpu/drm/vkms/vkms_drv.c
> > > @@ -51,6 +51,10 @@ static bool enable_overlay;
> > >   module_param_named(enable_overlay, enable_overlay, bool, 0444);
> > >   MODULE_PARM_DESC(enable_overlay, "Enable/Disable overlay support");
> > > 
> > > +static unsigned long background_color = 0x000000000000;
> > > +module_param_named(background_color, background_color, ulong, 0644);
> > > +MODULE_PARM_DESC(background_color, "Background color (0xRRRRGGGGBBBB)");
> > > +
> > >   DEFINE_DRM_GEM_FOPS(vkms_driver_fops);
> > > 
> > >   static void vkms_release(struct drm_device *dev)
> > > @@ -99,6 +103,7 @@ static int vkms_config_show(struct seq_file *m, void *data)
> > >          seq_printf(m, "writeback=%d\n", vkmsdev->config->writeback);
> > >          seq_printf(m, "cursor=%d\n", vkmsdev->config->cursor);
> > >          seq_printf(m, "overlay=%d\n", vkmsdev->config->overlay);
> > > +       seq_printf(m, "background_color=0x%lx\n", *vkmsdev->config->background_color);
> > > 
> > >          return 0;
> > >   }
> > > @@ -226,6 +231,7 @@ static int __init vkms_init(void)
> > >          config->cursor = enable_cursor;
> > >          config->writeback = enable_writeback;
> > >          config->overlay = enable_overlay;
> > > +       config->background_color = &background_color;
> > > 
> > >          ret = vkms_create(config);
> > >          if (ret)
> > > diff --git a/drivers/gpu/drm/vkms/vkms_drv.h b/drivers/gpu/drm/vkms/vkms_drv.h
> > > index 4a248567efb2..4bc2e6a6d219 100644
> > > --- a/drivers/gpu/drm/vkms/vkms_drv.h
> > > +++ b/drivers/gpu/drm/vkms/vkms_drv.h
> > > @@ -113,6 +113,7 @@ struct vkms_config {
> > >          bool writeback;
> > >          bool cursor;
> > >          bool overlay;
> > > +       unsigned long *background_color;
> > >          /* only set when instantiated */
> > >          struct vkms_device *dev;
> > >   };
> > > @@ -127,6 +128,9 @@ struct vkms_device {
> > >   #define drm_crtc_to_vkms_output(target) \
> > >          container_of(target, struct vkms_output, crtc)
> > > 
> > > +#define vkms_output_to_vkms_device(target) \
> > > +       container_of(target, struct vkms_device, output)
> > > +
> > >   #define drm_device_to_vkms_device(target) \
> > >          container_of(target, struct vkms_device, drm)
> > > 
> > > --
> > > 2.39.2
> > > 
> > 
> >
Maíra Canal April 6, 2023, 6:48 p.m. UTC | #4
On 4/6/23 15:23, Daniel Vetter wrote:
> On Thu, Apr 06, 2023 at 03:06:56PM -0300, Maíra Canal wrote:
>> On 4/6/23 14:28, Daniel Vetter wrote:
>>> On Thu, 6 Apr 2023 at 19:20, Maíra Canal <mcanal@igalia.com> wrote:
>>>>
>>>> After commit 8ba1648567e2 ("drm: vkms: Refactor the plane composer to
>>>> accept new formats") the composition is no longer performed on top of
>>>> the primary plane, but instead on top of the CRTC, which means that
>>>> now we have a background.
>>>>
>>>> This opens to the possibility of coloring the background with a
>>>> personalized color. Therefore, create a module parameter that takes a
>>>> unsigned long number as an XRGB16161616 color and set the background
>>>> color to it. That said, the composition will be performed on top of
>>>> this background color. By default, the background color is black.
>>>>
>>>> Signed-off-by: Maíra Canal <mcanal@igalia.com>
>>>> ---
>>>>
>>>> This patch intends to add a background color property to vkms through
>>>> a module parameter. Another option would be to implement this property
>>>> by adding a new KMS property that would indicate the background color.
>>>> It would be nice to hear other opinions on what would be the best
>>>> approach.
>>>
>>> These patches (and I think even igts for them) have been floating
>>> around for years. The hang-up is the userspace. Turns out all
>>> compositors want for background is black, thus far no one has figured
>>> out a real use-case for anything else.
>>>
>>> Maybe some time ...
>>>
>>
>> But, would it be okay to add this feature as a vkms' module parameter?
> 
> Yeah I think that's ok.
> 
>>>> Moreover, I wrote some IGT tests to ensure that the functionality is
>>>> working correctly [1]. The tests take the CRC of a colored primary
>>>> plane, offset the primary plane out of the screen, and take the CRC
>>>> of the colored background. The two CRC must be equal.
>>>>
>>>> [1] https://gitlab.freedesktop.org/mairacanal/igt-gpu-tools/-/tree/vkms/background-color
>>>
>>> I wonder whether it would be more useful to have this as a Kunit
>>> validation test to very that the vkms composing code works correctly?
>>> Still with the modparam and vkms_config to handle it all cleanly.
>>
>> Not sure if this would fit as a unit test, as the vkms composing
>> code basically outputs a CRC, which can be better verified by
>> the userspace. The output_buffer and stage_buffer are internal
>> variables, so it would be difficult to evaluate them with a KUnit
>> test.
>>
>> With the IGT test, we can assure that the background composition
>> is being performed properly using the CRC in a negative test and
>> also some positive tests.
> 
> I was just thinking of how you could keep the test, because igt is for
> uapi in general. So doesn't fit all that well, validating internals is
> more what kunit is supposed to do.

I'm not sure if testing the composition is an internal behavior, because
the output of the composition is a CRC that is exposed to the userspace.

Moreover, we need some sort of variable output to create a KUnit test,
which is not the case for vkms. The output_buffer and stage_buffer
are internal variables and they are overwritten on each iteration of
the blend loop.

As this property would be exclusive to vkms, I believe it would be okay
to add a vkms-specific IGT test to verify the correct behavior of the
background.

Best Regards,
- Maíra Canal

> -Daniel
> 
>>
>> Best Regards,
>> - Maíra Canal
>>
>>> -Daniel
>>>
>>>>
>>>> Best Regards,
>>>> - Maíra Canal
>>>>
>>>> ---
>>>>    Documentation/gpu/vkms.rst           |  2 --
>>>>    drivers/gpu/drm/vkms/vkms_composer.c | 20 ++++++++++++++------
>>>>    drivers/gpu/drm/vkms/vkms_drv.c      |  6 ++++++
>>>>    drivers/gpu/drm/vkms/vkms_drv.h      |  4 ++++
>>>>    4 files changed, 24 insertions(+), 8 deletions(-)
>>>>
>>>> diff --git a/Documentation/gpu/vkms.rst b/Documentation/gpu/vkms.rst
>>>> index 49db221c0f52..dc01689d8c76 100644
>>>> --- a/Documentation/gpu/vkms.rst
>>>> +++ b/Documentation/gpu/vkms.rst
>>>> @@ -121,8 +121,6 @@ There's lots of plane features we could add support for:
>>>>    - ARGB format on primary plane: blend the primary plane into background with
>>>>      translucent alpha.
>>>>
>>>> -- Add background color KMS property[Good to get started].
>>>> -
>>>>    - Full alpha blending on all planes.
>>>>
>>>>    - Rotation, scaling.
>>>> diff --git a/drivers/gpu/drm/vkms/vkms_composer.c b/drivers/gpu/drm/vkms/vkms_composer.c
>>>> index 8e53fa80742b..07345faee98a 100644
>>>> --- a/drivers/gpu/drm/vkms/vkms_composer.c
>>>> +++ b/drivers/gpu/drm/vkms/vkms_composer.c
>>>> @@ -79,7 +79,8 @@ static void fill_background(const struct pixel_argb_u16 *background_color,
>>>>     * from all planes, calculates the crc32 of the output from the former step,
>>>>     * and, if necessary, convert and store the output to the writeback buffer.
>>>>     */
>>>> -static void blend(struct vkms_writeback_job *wb,
>>>> +static void blend(struct vkms_device *vkms_dev,
>>>> +                 struct vkms_writeback_job *wb,
>>>>                     struct vkms_crtc_state *crtc_state,
>>>>                     u32 *crc32, struct line_buffer *stage_buffer,
>>>>                     struct line_buffer *output_buffer, size_t row_size)
>>>> @@ -87,7 +88,12 @@ static void blend(struct vkms_writeback_job *wb,
>>>>           struct vkms_plane_state **plane = crtc_state->active_planes;
>>>>           u32 n_active_planes = crtc_state->num_active_planes;
>>>>
>>>> -       const struct pixel_argb_u16 background_color = { .a = 0xffff };
>>>> +       const struct pixel_argb_u16 background_color = {
>>>> +               .a =  0xffff,
>>>> +               .r = (*vkms_dev->config->background_color >> 32) & 0xffff,
>>>> +               .g = (*vkms_dev->config->background_color >> 16) & 0xffff,
>>>> +               .b = *vkms_dev->config->background_color & 0xffff,
>>>> +       };
>>>>
>>>>           size_t crtc_y_limit = crtc_state->base.crtc->mode.vdisplay;
>>>>
>>>> @@ -139,7 +145,8 @@ static int check_iosys_map(struct vkms_crtc_state *crtc_state)
>>>>           return 0;
>>>>    }
>>>>
>>>> -static int compose_active_planes(struct vkms_writeback_job *active_wb,
>>>> +static int compose_active_planes(struct vkms_device *vkms_dev,
>>>> +                                struct vkms_writeback_job *active_wb,
>>>>                                    struct vkms_crtc_state *crtc_state,
>>>>                                    u32 *crc32)
>>>>    {
>>>> @@ -178,7 +185,7 @@ static int compose_active_planes(struct vkms_writeback_job *active_wb,
>>>>                   goto free_stage_buffer;
>>>>           }
>>>>
>>>> -       blend(active_wb, crtc_state, crc32, &stage_buffer,
>>>> +       blend(vkms_dev, active_wb, crtc_state, crc32, &stage_buffer,
>>>>                 &output_buffer, line_width * pixel_size);
>>>>
>>>>           kvfree(output_buffer.pixels);
>>>> @@ -205,6 +212,7 @@ void vkms_composer_worker(struct work_struct *work)
>>>>           struct drm_crtc *crtc = crtc_state->base.crtc;
>>>>           struct vkms_writeback_job *active_wb = crtc_state->active_writeback;
>>>>           struct vkms_output *out = drm_crtc_to_vkms_output(crtc);
>>>> +       struct vkms_device *vkms_dev = vkms_output_to_vkms_device(out);
>>>>           bool crc_pending, wb_pending;
>>>>           u64 frame_start, frame_end;
>>>>           u32 crc32 = 0;
>>>> @@ -228,9 +236,9 @@ void vkms_composer_worker(struct work_struct *work)
>>>>                   return;
>>>>
>>>>           if (wb_pending)
>>>> -               ret = compose_active_planes(active_wb, crtc_state, &crc32);
>>>> +               ret = compose_active_planes(vkms_dev, active_wb, crtc_state, &crc32);
>>>>           else
>>>> -               ret = compose_active_planes(NULL, crtc_state, &crc32);
>>>> +               ret = compose_active_planes(vkms_dev, NULL, crtc_state, &crc32);
>>>>
>>>>           if (ret)
>>>>                   return;
>>>> diff --git a/drivers/gpu/drm/vkms/vkms_drv.c b/drivers/gpu/drm/vkms/vkms_drv.c
>>>> index 6d3a2d57d992..a4938dcb8c3e 100644
>>>> --- a/drivers/gpu/drm/vkms/vkms_drv.c
>>>> +++ b/drivers/gpu/drm/vkms/vkms_drv.c
>>>> @@ -51,6 +51,10 @@ static bool enable_overlay;
>>>>    module_param_named(enable_overlay, enable_overlay, bool, 0444);
>>>>    MODULE_PARM_DESC(enable_overlay, "Enable/Disable overlay support");
>>>>
>>>> +static unsigned long background_color = 0x000000000000;
>>>> +module_param_named(background_color, background_color, ulong, 0644);
>>>> +MODULE_PARM_DESC(background_color, "Background color (0xRRRRGGGGBBBB)");
>>>> +
>>>>    DEFINE_DRM_GEM_FOPS(vkms_driver_fops);
>>>>
>>>>    static void vkms_release(struct drm_device *dev)
>>>> @@ -99,6 +103,7 @@ static int vkms_config_show(struct seq_file *m, void *data)
>>>>           seq_printf(m, "writeback=%d\n", vkmsdev->config->writeback);
>>>>           seq_printf(m, "cursor=%d\n", vkmsdev->config->cursor);
>>>>           seq_printf(m, "overlay=%d\n", vkmsdev->config->overlay);
>>>> +       seq_printf(m, "background_color=0x%lx\n", *vkmsdev->config->background_color);
>>>>
>>>>           return 0;
>>>>    }
>>>> @@ -226,6 +231,7 @@ static int __init vkms_init(void)
>>>>           config->cursor = enable_cursor;
>>>>           config->writeback = enable_writeback;
>>>>           config->overlay = enable_overlay;
>>>> +       config->background_color = &background_color;
>>>>
>>>>           ret = vkms_create(config);
>>>>           if (ret)
>>>> diff --git a/drivers/gpu/drm/vkms/vkms_drv.h b/drivers/gpu/drm/vkms/vkms_drv.h
>>>> index 4a248567efb2..4bc2e6a6d219 100644
>>>> --- a/drivers/gpu/drm/vkms/vkms_drv.h
>>>> +++ b/drivers/gpu/drm/vkms/vkms_drv.h
>>>> @@ -113,6 +113,7 @@ struct vkms_config {
>>>>           bool writeback;
>>>>           bool cursor;
>>>>           bool overlay;
>>>> +       unsigned long *background_color;
>>>>           /* only set when instantiated */
>>>>           struct vkms_device *dev;
>>>>    };
>>>> @@ -127,6 +128,9 @@ struct vkms_device {
>>>>    #define drm_crtc_to_vkms_output(target) \
>>>>           container_of(target, struct vkms_output, crtc)
>>>>
>>>> +#define vkms_output_to_vkms_device(target) \
>>>> +       container_of(target, struct vkms_device, output)
>>>> +
>>>>    #define drm_device_to_vkms_device(target) \
>>>>           container_of(target, struct vkms_device, drm)
>>>>
>>>> --
>>>> 2.39.2
>>>>
>>>
>>>
>
kernel test robot April 6, 2023, 9:06 p.m. UTC | #5
Hi Maíra,

kernel test robot noticed the following build warnings:

[auto build test WARNING on drm-misc/drm-misc-next]
[also build test WARNING on drm-intel/for-linux-next drm-intel/for-linux-next-fixes drm-tip/drm-tip linus/master v6.3-rc5 next-20230406]
[If your patch is applied to the wrong git tree, kindly drop us a note.
And when submitting patch, we suggest to use '--base' as documented in
https://git-scm.com/docs/git-format-patch#_base_tree_information]

url:    https://github.com/intel-lab-lkp/linux/commits/Ma-ra-Canal/drm-vkms-add-module-parameter-to-set-background-color/20230407-012233
base:   git://anongit.freedesktop.org/drm/drm-misc drm-misc-next
patch link:    https://lore.kernel.org/r/20230406172002.124456-1-mcanal%40igalia.com
patch subject: [PATCH] drm/vkms: add module parameter to set background color
config: powerpc-allmodconfig (https://download.01.org/0day-ci/archive/20230407/202304070429.B1aKOT5a-lkp@intel.com/config)
compiler: powerpc-linux-gcc (GCC) 12.1.0
reproduce (this is a W=1 build):
        wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
        chmod +x ~/bin/make.cross
        # https://github.com/intel-lab-lkp/linux/commit/d725068207852d3b6a0dd795bf224422804101e1
        git remote add linux-review https://github.com/intel-lab-lkp/linux
        git fetch --no-tags linux-review Ma-ra-Canal/drm-vkms-add-module-parameter-to-set-background-color/20230407-012233
        git checkout d725068207852d3b6a0dd795bf224422804101e1
        # save the config file
        mkdir build_dir && cp config build_dir/.config
        COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-12.1.0 make.cross W=1 O=build_dir ARCH=powerpc olddefconfig
        COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-12.1.0 make.cross W=1 O=build_dir ARCH=powerpc SHELL=/bin/bash drivers/gpu/

If you fix the issue, kindly add following tag where applicable
| Reported-by: kernel test robot <lkp@intel.com>
| Link: https://lore.kernel.org/oe-kbuild-all/202304070429.B1aKOT5a-lkp@intel.com/

All warnings (new ones prefixed by >>):

   drivers/gpu/drm/vkms/vkms_composer.c: In function 'blend':
>> drivers/gpu/drm/vkms/vkms_composer.c:93:59: warning: right shift count >= width of type [-Wshift-count-overflow]
      93 |                 .r = (*vkms_dev->config->background_color >> 32) & 0xffff,
         |                                                           ^~


vim +93 drivers/gpu/drm/vkms/vkms_composer.c

    70	
    71	/**
    72	 * @wb_frame_info: The writeback frame buffer metadata
    73	 * @crtc_state: The crtc state
    74	 * @crc32: The crc output of the final frame
    75	 * @output_buffer: A buffer of a row that will receive the result of the blend(s)
    76	 * @stage_buffer: The line with the pixels from plane being blend to the output
    77	 *
    78	 * This function blends the pixels (Using the `pre_mul_alpha_blend`)
    79	 * from all planes, calculates the crc32 of the output from the former step,
    80	 * and, if necessary, convert and store the output to the writeback buffer.
    81	 */
    82	static void blend(struct vkms_device *vkms_dev,
    83			  struct vkms_writeback_job *wb,
    84			  struct vkms_crtc_state *crtc_state,
    85			  u32 *crc32, struct line_buffer *stage_buffer,
    86			  struct line_buffer *output_buffer, size_t row_size)
    87	{
    88		struct vkms_plane_state **plane = crtc_state->active_planes;
    89		u32 n_active_planes = crtc_state->num_active_planes;
    90	
    91		const struct pixel_argb_u16 background_color = {
    92			.a =  0xffff,
  > 93			.r = (*vkms_dev->config->background_color >> 32) & 0xffff,
    94			.g = (*vkms_dev->config->background_color >> 16) & 0xffff,
    95			.b = *vkms_dev->config->background_color & 0xffff,
    96		};
    97	
    98		size_t crtc_y_limit = crtc_state->base.crtc->mode.vdisplay;
    99	
   100		for (size_t y = 0; y < crtc_y_limit; y++) {
   101			fill_background(&background_color, output_buffer);
   102	
   103			/* The active planes are composed associatively in z-order. */
   104			for (size_t i = 0; i < n_active_planes; i++) {
   105				if (!check_y_limit(plane[i]->frame_info, y))
   106					continue;
   107	
   108				plane[i]->plane_read(stage_buffer, plane[i]->frame_info, y);
   109				pre_mul_alpha_blend(plane[i]->frame_info, stage_buffer,
   110						    output_buffer);
   111			}
   112	
   113			*crc32 = crc32_le(*crc32, (void *)output_buffer->pixels, row_size);
   114	
   115			if (wb)
   116				wb->wb_write(&wb->wb_frame_info, output_buffer, y);
   117		}
   118	}
   119
Dan Carpenter April 11, 2023, 8:26 a.m. UTC | #6
Hi Maíra,

kernel test robot noticed the following build warnings:

https://git-scm.com/docs/git-format-patch#_base_tree_information]

url:    https://github.com/intel-lab-lkp/linux/commits/Ma-ra-Canal/drm-vkms-add-module-parameter-to-set-background-color/20230407-012233
base:   git://anongit.freedesktop.org/drm/drm-misc drm-misc-next
patch link:    https://lore.kernel.org/r/20230406172002.124456-1-mcanal%40igalia.com
patch subject: [PATCH] drm/vkms: add module parameter to set background color
config: i386-randconfig-m031-20230403 (https://download.01.org/0day-ci/archive/20230408/202304082018.PXAwWhse-lkp@intel.com/config)
compiler: gcc-11 (Debian 11.3.0-8) 11.3.0

If you fix the issue, kindly add following tag where applicable
| Reported-by: kernel test robot <lkp@intel.com>
| Reported-by: Dan Carpenter <error27@gmail.com>
| Link: https://lore.kernel.org/r/202304082018.PXAwWhse-lkp@intel.com/

smatch warnings:
drivers/gpu/drm/vkms/vkms_composer.c:93 blend() warn: right shifting more than type allows 32 vs 32

vim +93 drivers/gpu/drm/vkms/vkms_composer.c

d725068207852d drivers/gpu/drm/vkms/vkms_composer.c Maíra Canal     2023-04-06   82  static void blend(struct vkms_device *vkms_dev,
d725068207852d drivers/gpu/drm/vkms/vkms_composer.c Maíra Canal     2023-04-06   83  		  struct vkms_writeback_job *wb,
8ba1648567e289 drivers/gpu/drm/vkms/vkms_composer.c Igor Torrente   2022-09-05   84  		  struct vkms_crtc_state *crtc_state,
8ba1648567e289 drivers/gpu/drm/vkms/vkms_composer.c Igor Torrente   2022-09-05   85  		  u32 *crc32, struct line_buffer *stage_buffer,
8ba1648567e289 drivers/gpu/drm/vkms/vkms_composer.c Igor Torrente   2022-09-05   86  		  struct line_buffer *output_buffer, size_t row_size)
39cba5cf8c2c23 drivers/gpu/drm/vkms/vkms_composer.c Melissa Wen     2020-08-25   87  {
8ba1648567e289 drivers/gpu/drm/vkms/vkms_composer.c Igor Torrente   2022-09-05   88  	struct vkms_plane_state **plane = crtc_state->active_planes;
8ba1648567e289 drivers/gpu/drm/vkms/vkms_composer.c Igor Torrente   2022-09-05   89  	u32 n_active_planes = crtc_state->num_active_planes;
39cba5cf8c2c23 drivers/gpu/drm/vkms/vkms_composer.c Melissa Wen     2020-08-25   90  
d725068207852d drivers/gpu/drm/vkms/vkms_composer.c Maíra Canal     2023-04-06   91  	const struct pixel_argb_u16 background_color = {
d725068207852d drivers/gpu/drm/vkms/vkms_composer.c Maíra Canal     2023-04-06   92  		.a =  0xffff,
d725068207852d drivers/gpu/drm/vkms/vkms_composer.c Maíra Canal     2023-04-06  @93  		.r = (*vkms_dev->config->background_color >> 32) & 0xffff,
                                                                                                       ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
This shift always results in zero.

d725068207852d drivers/gpu/drm/vkms/vkms_composer.c Maíra Canal     2023-04-06   94  		.g = (*vkms_dev->config->background_color >> 16) & 0xffff,
d725068207852d drivers/gpu/drm/vkms/vkms_composer.c Maíra Canal     2023-04-06   95  		.b = *vkms_dev->config->background_color & 0xffff,
d725068207852d drivers/gpu/drm/vkms/vkms_composer.c Maíra Canal     2023-04-06   96  	};
32a1648aca4409 drivers/gpu/drm/vkms/vkms_composer.c Melissa Wen     2021-04-24   97  
bc0d7fdefec62e drivers/gpu/drm/vkms/vkms_composer.c Igor Torrente   2022-09-05   98  	size_t crtc_y_limit = crtc_state->base.crtc->mode.vdisplay;
39cba5cf8c2c23 drivers/gpu/drm/vkms/vkms_composer.c Melissa Wen     2020-08-25   99  
bc0d7fdefec62e drivers/gpu/drm/vkms/vkms_composer.c Igor Torrente   2022-09-05  100  	for (size_t y = 0; y < crtc_y_limit; y++) {
bc0d7fdefec62e drivers/gpu/drm/vkms/vkms_composer.c Igor Torrente   2022-09-05  101  		fill_background(&background_color, output_buffer);
bc0d7fdefec62e drivers/gpu/drm/vkms/vkms_composer.c Igor Torrente   2022-09-05  102  
bc0d7fdefec62e drivers/gpu/drm/vkms/vkms_composer.c Igor Torrente   2022-09-05  103  		/* The active planes are composed associatively in z-order. */
bc0d7fdefec62e drivers/gpu/drm/vkms/vkms_composer.c Igor Torrente   2022-09-05  104  		for (size_t i = 0; i < n_active_planes; i++) {
8ba1648567e289 drivers/gpu/drm/vkms/vkms_composer.c Igor Torrente   2022-09-05  105  			if (!check_y_limit(plane[i]->frame_info, y))
8ba1648567e289 drivers/gpu/drm/vkms/vkms_composer.c Igor Torrente   2022-09-05  106  				continue;
8ba1648567e289 drivers/gpu/drm/vkms/vkms_composer.c Igor Torrente   2022-09-05  107  
8ba1648567e289 drivers/gpu/drm/vkms/vkms_composer.c Igor Torrente   2022-09-05  108  			plane[i]->plane_read(stage_buffer, plane[i]->frame_info, y);
8ba1648567e289 drivers/gpu/drm/vkms/vkms_composer.c Igor Torrente   2022-09-05  109  			pre_mul_alpha_blend(plane[i]->frame_info, stage_buffer,
8ba1648567e289 drivers/gpu/drm/vkms/vkms_composer.c Igor Torrente   2022-09-05  110  					    output_buffer);
db7f419c06d7cc drivers/gpu/drm/vkms/vkms_crc.c      Haneen Mohammed 2018-09-06  111  		}
8ba1648567e289 drivers/gpu/drm/vkms/vkms_composer.c Igor Torrente   2022-09-05  112  
8ba1648567e289 drivers/gpu/drm/vkms/vkms_composer.c Igor Torrente   2022-09-05  113  		*crc32 = crc32_le(*crc32, (void *)output_buffer->pixels, row_size);
8ba1648567e289 drivers/gpu/drm/vkms/vkms_composer.c Igor Torrente   2022-09-05  114  
8ba1648567e289 drivers/gpu/drm/vkms/vkms_composer.c Igor Torrente   2022-09-05  115  		if (wb)
8ba1648567e289 drivers/gpu/drm/vkms/vkms_composer.c Igor Torrente   2022-09-05  116  			wb->wb_write(&wb->wb_frame_info, output_buffer, y);
db7f419c06d7cc drivers/gpu/drm/vkms/vkms_crc.c      Haneen Mohammed 2018-09-06  117  	}
db7f419c06d7cc drivers/gpu/drm/vkms/vkms_crc.c      Haneen Mohammed 2018-09-06  118  }
diff mbox series

Patch

diff --git a/Documentation/gpu/vkms.rst b/Documentation/gpu/vkms.rst
index 49db221c0f52..dc01689d8c76 100644
--- a/Documentation/gpu/vkms.rst
+++ b/Documentation/gpu/vkms.rst
@@ -121,8 +121,6 @@  There's lots of plane features we could add support for:
 - ARGB format on primary plane: blend the primary plane into background with
   translucent alpha.
 
-- Add background color KMS property[Good to get started].
-
 - Full alpha blending on all planes.
 
 - Rotation, scaling.
diff --git a/drivers/gpu/drm/vkms/vkms_composer.c b/drivers/gpu/drm/vkms/vkms_composer.c
index 8e53fa80742b..07345faee98a 100644
--- a/drivers/gpu/drm/vkms/vkms_composer.c
+++ b/drivers/gpu/drm/vkms/vkms_composer.c
@@ -79,7 +79,8 @@  static void fill_background(const struct pixel_argb_u16 *background_color,
  * from all planes, calculates the crc32 of the output from the former step,
  * and, if necessary, convert and store the output to the writeback buffer.
  */
-static void blend(struct vkms_writeback_job *wb,
+static void blend(struct vkms_device *vkms_dev,
+		  struct vkms_writeback_job *wb,
 		  struct vkms_crtc_state *crtc_state,
 		  u32 *crc32, struct line_buffer *stage_buffer,
 		  struct line_buffer *output_buffer, size_t row_size)
@@ -87,7 +88,12 @@  static void blend(struct vkms_writeback_job *wb,
 	struct vkms_plane_state **plane = crtc_state->active_planes;
 	u32 n_active_planes = crtc_state->num_active_planes;
 
-	const struct pixel_argb_u16 background_color = { .a = 0xffff };
+	const struct pixel_argb_u16 background_color = {
+		.a =  0xffff,
+		.r = (*vkms_dev->config->background_color >> 32) & 0xffff,
+		.g = (*vkms_dev->config->background_color >> 16) & 0xffff,
+		.b = *vkms_dev->config->background_color & 0xffff,
+	};
 
 	size_t crtc_y_limit = crtc_state->base.crtc->mode.vdisplay;
 
@@ -139,7 +145,8 @@  static int check_iosys_map(struct vkms_crtc_state *crtc_state)
 	return 0;
 }
 
-static int compose_active_planes(struct vkms_writeback_job *active_wb,
+static int compose_active_planes(struct vkms_device *vkms_dev,
+				 struct vkms_writeback_job *active_wb,
 				 struct vkms_crtc_state *crtc_state,
 				 u32 *crc32)
 {
@@ -178,7 +185,7 @@  static int compose_active_planes(struct vkms_writeback_job *active_wb,
 		goto free_stage_buffer;
 	}
 
-	blend(active_wb, crtc_state, crc32, &stage_buffer,
+	blend(vkms_dev, active_wb, crtc_state, crc32, &stage_buffer,
 	      &output_buffer, line_width * pixel_size);
 
 	kvfree(output_buffer.pixels);
@@ -205,6 +212,7 @@  void vkms_composer_worker(struct work_struct *work)
 	struct drm_crtc *crtc = crtc_state->base.crtc;
 	struct vkms_writeback_job *active_wb = crtc_state->active_writeback;
 	struct vkms_output *out = drm_crtc_to_vkms_output(crtc);
+	struct vkms_device *vkms_dev = vkms_output_to_vkms_device(out);
 	bool crc_pending, wb_pending;
 	u64 frame_start, frame_end;
 	u32 crc32 = 0;
@@ -228,9 +236,9 @@  void vkms_composer_worker(struct work_struct *work)
 		return;
 
 	if (wb_pending)
-		ret = compose_active_planes(active_wb, crtc_state, &crc32);
+		ret = compose_active_planes(vkms_dev, active_wb, crtc_state, &crc32);
 	else
-		ret = compose_active_planes(NULL, crtc_state, &crc32);
+		ret = compose_active_planes(vkms_dev, NULL, crtc_state, &crc32);
 
 	if (ret)
 		return;
diff --git a/drivers/gpu/drm/vkms/vkms_drv.c b/drivers/gpu/drm/vkms/vkms_drv.c
index 6d3a2d57d992..a4938dcb8c3e 100644
--- a/drivers/gpu/drm/vkms/vkms_drv.c
+++ b/drivers/gpu/drm/vkms/vkms_drv.c
@@ -51,6 +51,10 @@  static bool enable_overlay;
 module_param_named(enable_overlay, enable_overlay, bool, 0444);
 MODULE_PARM_DESC(enable_overlay, "Enable/Disable overlay support");
 
+static unsigned long background_color = 0x000000000000;
+module_param_named(background_color, background_color, ulong, 0644);
+MODULE_PARM_DESC(background_color, "Background color (0xRRRRGGGGBBBB)");
+
 DEFINE_DRM_GEM_FOPS(vkms_driver_fops);
 
 static void vkms_release(struct drm_device *dev)
@@ -99,6 +103,7 @@  static int vkms_config_show(struct seq_file *m, void *data)
 	seq_printf(m, "writeback=%d\n", vkmsdev->config->writeback);
 	seq_printf(m, "cursor=%d\n", vkmsdev->config->cursor);
 	seq_printf(m, "overlay=%d\n", vkmsdev->config->overlay);
+	seq_printf(m, "background_color=0x%lx\n", *vkmsdev->config->background_color);
 
 	return 0;
 }
@@ -226,6 +231,7 @@  static int __init vkms_init(void)
 	config->cursor = enable_cursor;
 	config->writeback = enable_writeback;
 	config->overlay = enable_overlay;
+	config->background_color = &background_color;
 
 	ret = vkms_create(config);
 	if (ret)
diff --git a/drivers/gpu/drm/vkms/vkms_drv.h b/drivers/gpu/drm/vkms/vkms_drv.h
index 4a248567efb2..4bc2e6a6d219 100644
--- a/drivers/gpu/drm/vkms/vkms_drv.h
+++ b/drivers/gpu/drm/vkms/vkms_drv.h
@@ -113,6 +113,7 @@  struct vkms_config {
 	bool writeback;
 	bool cursor;
 	bool overlay;
+	unsigned long *background_color;
 	/* only set when instantiated */
 	struct vkms_device *dev;
 };
@@ -127,6 +128,9 @@  struct vkms_device {
 #define drm_crtc_to_vkms_output(target) \
 	container_of(target, struct vkms_output, crtc)
 
+#define vkms_output_to_vkms_device(target) \
+	container_of(target, struct vkms_device, output)
+
 #define drm_device_to_vkms_device(target) \
 	container_of(target, struct vkms_device, drm)