Re-introduce a line-by-line composition algorithm for each pixel format.
This allows more performance by not requiring an indirection per pixel
read. This patch is focused on readability of the code.
Line-by-line composition was introduced by [1] but rewritten back to
pixel-by-pixel algorithm in [2]. At this time, nobody noticed the impact
on performance, and it was merged.
This patch is almost a revert of [2], but in addition efforts have been
made to increase readability and maintainability of the rotation handling.
The blend function is now divided in two parts:
- Transformation of coordinates from the output referential to the source
referential
- Line conversion and blending
Most of the complexity of the rotation management is avoided by using
drm_rect_* helpers. The remaining complexity is around the clipping, to
avoid reading/writing outside source/destination buffers.
The pixel conversion is now done line-by-line, so the read_pixel_t was
replaced with read_pixel_line_t callback. This way the indirection is only
required once per line and per plane, instead of once per pixel and per
plane.
The read_line_t callbacks are very similar for most pixel format, but it
is required to avoid performance impact. Some helpers for color
conversion were introduced to avoid code repetition:
- *_to_argb_u16: perform colors conversion. They should be inlined by the
compiler, and they are used to avoid repetition between multiple variants
of the same format (argb/xrgb and maybe in the future for formats like
bgr formats).
This new algorithm was tested with:
- kms_plane (for color conversions)
- kms_rotation_crc (for rotations of planes)
- kms_cursor_crc (for translations of planes)
- kms_rotation (for all rotations and formats combinations) [3]
The performance gain was mesured with kms_fb_stress [4] with some
modification to fix the writeback format.
The performance improvement is around 5 to 10%.
[1]: commit 8ba1648567 ("drm: vkms: Refactor the plane composer to accept
new formats")
https://lore.kernel.org/all/20220905190811.25024-7-igormtorrente@gmail.com/
[2]: commit 322d716a3e ("drm/vkms: isolate pixel conversion
functionality")
https://lore.kernel.org/all/20230418130525.128733-2-mcanal@igalia.com/
[3]: https://lore.kernel.org/igt-dev/20240313-new_rotation-v2-0-6230fd5cae59@bootlin.com/
[4]: https://lore.kernel.org/all/20240422-kms_fb_stress-dev-v5-0-0c577163dc88@riseup.net/
Reviewed-by: José Expósito <jose.exposito89@gmail.com>
Acked-by: Pekka Paalanen <pekka.paalanen@collabora.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20241118-yuv-v14-8-2dbc2f1e222c@bootlin.com
Signed-off-by: Louis Chauvet <louis.chauvet@bootlin.com>
The pixel_read_direction enum is useful to describe the reading direction
in a plane. It avoids using the rotation property of DRM, which not
practical to know the direction of reading.
This patch also introduce two helpers, one to compute the
pixel_read_direction from the DRM rotation property, and one to compute
the step, in byte, between two successive pixel in a specific direction.
Acked-by: Maíra Canal <mairacanal@riseup.net>
Reviewed-by: José Expósito <jose.exposito89@gmail.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20241118-yuv-v14-7-2dbc2f1e222c@bootlin.com
Signed-off-by: Louis Chauvet <louis.chauvet@bootlin.com>
Introduce the usage of block_h/block_w to compute the offset and the
pointer of a pixel. The previous implementation was specialized for
planes with block_h == block_w == 1. To avoid confusion and allow easier
implementation of tiled formats. It also remove the usage of the
deprecated format field `cpp`.
Introduce the plane_index parameter to get an offset/pointer on a
different plane.
Acked-by: Maíra Canal <mairacanal@riseup.net>
Reviewed-by: José Expósito <jose.exposito89@gmail.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20241118-yuv-v14-5-2dbc2f1e222c@bootlin.com
Signed-off-by: Louis Chauvet <louis.chauvet@bootlin.com>
Introduce two typedefs: pixel_read_t and pixel_write_t. It allows the
compiler to check if the passed functions take the correct arguments.
Such typedefs will help ensuring consistency across the code base in
case of update of these prototypes.
Rename input/output variable in a consistent way between read_line and
write_line.
A warn has been added in get_pixel_*_function to alert when an unsupported
pixel format is requested. As those formats are checked before
atomic_update callbacks, it should never happen.
Document for those typedefs.
Reviewed-by: Pekka Paalanen <pekka.paalanen@collabora.com>
Reviewed-by: José Expósito <jose.exposito89@gmail.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20241118-yuv-v14-3-2dbc2f1e222c@bootlin.com
Signed-off-by: Louis Chauvet <louis.chauvet@bootlin.com>
VKMS currently supports only one CRTC, so it make no sense to have this
index configurable. To avoid issues, replace this hardcoded index by
drm_crtc_mask when applicable.
There is no need to manually set a crtc mask on primary and cursor plane
as it is automatically set by drmm_crtc_alloc_with_planes.
In addition, this will remove the use of an uninitialized structure in
vkms_add_overlay_plane. This currently works by chance because two things:
- vkms_plane_init always set a possible_crtcs value, so the problematic
branch is never used;
- drm_crtc_mask on an kzalloc'd drm_crtc returns BIT(0), and the VKMS CRTC
always have this id.
Reviewed-by: José Expósito <jose.exposito89@gmail.com>
Reviewed-by: Maíra Canal <mcanal@igalia.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20241119-vkms-remove-index-v3-1-976321a3f801@bootlin.com
Signed-off-by: Louis Chauvet <louis.chauvet@bootlin.com>
The drm_atomic_helper_check_wb_encoder_state() function doesn't use
encoder for anything other than getting the drm_device instance. The
function's description talks about checking the writeback connector
state, not the encoder state. Moreover, there is no such thing as an
encoder state, encoders generally do not have a state on their own.
Rename the function to drm_atomic_helper_check_wb_connector_state()
and change arguments to drm_writeback_connector and drm_atomic_state.
Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
Signed-off-by: Maxime Ripard <mripard@kernel.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20231208010314.3395904-2-dmitry.baryshkov@linaro.org
Currently, it is possible for the composer to be set as enabled and then
as disabled without a proper call for the vkms_vblank_simulate(). This
is problematic, because the driver would skip one CRC output, causing CRC
tests to fail. Therefore, we need to make sure that, for each time the
composer is set as enabled, a composer job is added to the queue.
In order to provide this guarantee, add a mutex that will lock before
the composer is set as enabled and will unlock only after the composer
job is added to the queue. This way, we can have a guarantee that the
driver won't skip a CRC entry.
This race-condition is affecting the IGT test "writeback-check-output",
making the test fail and also, leaking writeback framebuffers, as the
writeback job is queued, but it is not signaled. This patch avoids both
problems.
[v2]:
* Create a new mutex and keep the spinlock across the atomic commit in
order to avoid interrupts that could result in deadlocks.
Signed-off-by: Maíra Canal <mcanal@igalia.com>
Reviewed-by: Arthur Grillo <arthurgrillo@riseup.net>
Signed-off-by: Maíra Canal <mairacanal@riseup.net>
Link: https://patchwork.freedesktop.org/patch/msgid/20230523123207.173976-1-mcanal@igalia.com
Support a 1D gamma LUT with interpolation for each color channel on the
VKMS driver. Add a check for the LUT length by creating
vkms_atomic_check().
Enable VKMS to run the test igt@kms_plane@pixel-format.
Tested with:
igt@kms_color@gamma
igt@kms_color@legacy-gamma
igt@kms_color@invalid-gamma-lut-sizes
v2:
- Add interpolation between the values of the LUT (Simon Ser)
v3:
- s/ratio/delta (Pekka)
- s/color_channel/channel_value (Pekka)
- s/lut_area/lut_channel
- Store the `drm_color_lut`, `lut_length`, and
`channel_value2index_ratio` inside a struct called `vkms_lut`
(Pekka)
- Pre-compute some constants values used through the LUT procedure
(Pekka)
- Change the switch statement to a cast to __u16* (Pekka)
- Make the apply_lut_to_channel_value return the computation result
(Pekka)
v4:
- Add a comment explaining that `enum lut_area` depends on the
layout of `struct drm_color_lut` (Pekka)
- Remove unused variable (kernel test robot)
v5:
- Mention that this will make it possible to run the test
igt@kms_plane@pixel-format (Maíra)
- s/had/has (Maíra)
Signed-off-by: Arthur Grillo <arthurgrillo@riseup.net>
Acked-by: Pekka Paalanen <pekka.paalanen@collabora.com>
Reviewed-by: Harry Wentland <harry.wentland@amd.com>
Reviewed-by: Maíra Canal <mairacanal@riseup.net>
Signed-off-by: Maíra Canal <mairacanal@riseup.net>
Link: https://patchwork.freedesktop.org/patch/msgid/20230709013835.161004-1-arthurgrillo@riseup.net
The spinlock composer_lock protects the variables crc_pending,
wb_pending, frame_start and frame_end, which are variables that are used
by the composer worker. There is no need to protect the wb_frame_info
information with a spinlock. Therefore, reduce the critical section of
the lock by removing the assignments to the wb_frame_info from the
critical section.
Signed-off-by: Maíra Canal <mcanal@igalia.com>
Reviewed-by: Arthur Grillo <arthurgrillo@riseup.net>
Signed-off-by: Maíra Canal <mairacanal@riseup.net>
Link: https://patchwork.freedesktop.org/patch/msgid/20230515135204.115393-2-mcanal@igalia.com
Fix the following warnings:
drivers/gpu/drm/vkms/vkms_composer.c:42: warning: Function parameter or member 'frame_info' not described in 'pre_mul_alpha_blend'
drivers/gpu/drm/vkms/vkms_composer.c:42: warning: Excess function parameter 'src_frame_info' description in 'pre_mul_alpha_blend'
drivers/gpu/drm/vkms/vkms_composer.c:93: warning: Cannot understand * @wb_frame_info: The writeback frame buffer metadata
on line 93 - I thought it was a doc line
by correcting variable names and adding function name.
Signed-off-by: Maíra Canal <mcanal@igalia.com>
Reviewed-by: Javier Martinez Canillas <javierm@redhat.com>
Signed-off-by: Maíra Canal <mairacanal@riseup.net>
Link: https://patchwork.freedesktop.org/patch/msgid/20230508220030.434118-2-mcanal@igalia.com
Currently, the pixel conversion isn't rounding the fixed-point values
before assigning it to the RGB coefficients, which is causing the IGT
pixel-format tests to fail. So, use the drm_fixp2int_round() fixed-point
helper to round the values when assigning it to the RGB coefficients.
Tested with igt@kms_plane@pixel-format and igt@kms_plane@pixel-format-source-clamping.
[v2]:
* Use drm_fixp2int_round() to fix the pixel conversion instead of
casting the values to s32 (Melissa Wen).
Fixes: 89b03aeaef ("drm/vkms: fix 32bit compilation error by replacing macros")
Signed-off-by: Maíra Canal <mcanal@igalia.com>
Reviewed-by: Arthur Grillo <arthurgrillo@riseup.net>
Signed-off-by: Maíra Canal <mairacanal@riseup.net>
Link: https://patchwork.freedesktop.org/patch/msgid/20230512104044.65034-2-mcanal@igalia.com
Currently, vkms supports the rotate-90, rotate-180, reflect-x and
reflect-y properties. Therefore, improve the vkms IGT test coverage by
adding the rotate-270 property to vkms. The rotation was implement by
software: rotate the way the blending occurs by making the source x axis
be the destination y axis and the source y axis be the destination x
axis and reverse-read the axis.
Now, vkms supports all possible rotation values.
Tested with igt@kms_rotation_crc@primary-rotation-270 [1],
and igt@kms_rotation_crc@sprite-rotation-270 [1].
[1] https://patchwork.freedesktop.org/series/116025/
Signed-off-by: Maíra Canal <mcanal@igalia.com>
Reviewed-by: Melissa Wen <mwen@igalia.com>
Signed-off-by: Maíra Canal <mairacanal@riseup.net>
Link: https://patchwork.freedesktop.org/patch/msgid/20230418130525.128733-6-mcanal@igalia.com
Currently, vkms only supports the rotate-180, reflect-x and reflect-y
properties. Therefore, improve the vkms IGT test coverage by adding the
rotate-90 property to vkms. The rotation was implement by software: rotate
the way the blending occurs by making the source x axis be the destination
y axis and the source y axis be the destination x axis.
Tested with igt@kms_rotation_crc@primary-rotation-90 [1],
igt@kms_rotation_crc@sprite-rotation-90 [1], and
igt@kms_rotation_crc@sprite-rotation-90-pos-100-0 [1].
[1] https://patchwork.freedesktop.org/series/116025/
Signed-off-by: Maíra Canal <mcanal@igalia.com>
Reviewed-by: Melissa Wen <mwen@igalia.com>
Signed-off-by: Maíra Canal <mairacanal@riseup.net>
Link: https://patchwork.freedesktop.org/patch/msgid/20230418130525.128733-5-mcanal@igalia.com
Currently, vkms only supports the reflect-x property. Therefore, add the
reflect-y property to vkms through a software implementation of the
operation. This is possible by reverse reading the y axis during the
blending.
Note that, by implementing the reflect-x and reflect-y properties, it is
also possible to add the rotate-180 property, as it is a combination
of those two properties.
Tested with igt@kms_rotation_crc@primary-reflect-y [1],
igt@kms_rotation_crc@sprite-reflect-y [1],
igt@kms_rotation_crc@primary-rotation-180,
igt@kms_rotation_crc@sprite-rotation-180,
and igt@kms_rotation_crc@cursor-rotation-180.
[1] https://patchwork.freedesktop.org/series/116025/
Signed-off-by: Maíra Canal <mcanal@igalia.com>
Reviewed-by: Melissa Wen <mwen@igalia.com>
Signed-off-by: Maíra Canal <mairacanal@riseup.net>
Link: https://patchwork.freedesktop.org/patch/msgid/20230418130525.128733-4-mcanal@igalia.com
The driver doesn't use simple-KMS helpers to set a simple display pipeline
but only the drm_simple_encoder_init() function to initialize an encoder.
That helper is just a wrapper of drm_encoder_init(), but passing a struct
drm_encoder_funcs that sets the .destroy handler to drm_encoder_cleanup().
Since the <drm/drm_simple_kms_helper.h> header is only included for this
helper and because the connector is initialized with drm_connector_init()
as well, do the same for the encoder and drop the header include.
Signed-off-by: Javier Martinez Canillas <javierm@redhat.com>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Reviewed-by: Thomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: Maíra Canal <mcanal@igalia.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20230406110235.3092055-3-javierm@redhat.com
Before commit bc0d7fdefe ("drm: vkms: Supports to the case where
primary plane doesn't match the CRTC"), the composition was executed
on top of the primary plane. Therefore, the primary plane needed to cover
the entire CRTC. After commit bc0d7fdefe, this is no longer necessary,
as the composition is now executed on top of the CRTC.
Then, allow the primary plane to be positioned in such a way that it
doesn't cover the entire CRTC.
This patch was tested with the vkms IGT testlist and all tests passed
successfully. Moreover, the test
igt@kms_universal_plane@universal-plane-pageflip-windowed-pipe-A
used to fail and now is passing.
Signed-off-by: Maíra Canal <mcanal@igalia.com>
Reviewed-by: Melissa Wen <mwen@igalia.com>
Signed-off-by: Maíra Canal <mairacanal@riseup.net>
Link: https://patchwork.freedesktop.org/patch/msgid/20230324164226.256084-3-mcanal@igalia.com
Before commit bc0d7fdefe ("drm: vkms: Supports to the case where
primary plane doesn't match the CRTC"), the composition was executed on
top of the primary plane. Therefore, the primary plane needed to be
visible and full screen. After commit bc0d7fdefe, this is no longer
necessary, as the composition is now executed on top of the CRTC.
Then, remove the conditional expression that forced the primary plane to
be visible and full screen. This allows vkms to accept non-null
framebuffers when the CRTC is disabled.
This patch was tested with the vkms IGT testlist and all tests passed
successfully. Moreover, the tests
igt@kms_universal_plane@universal-plane-pipe-a-functional and
igt@kms_universal_plane@disable-primary-vs-flip-pipe-a used to fail and
now are passing.
Signed-off-by: Maíra Canal <mcanal@igalia.com>
Reviewed-by: Melissa Wen <mwen@igalia.com>
Signed-off-by: Maíra Canal <mairacanal@riseup.net>
Link: https://patchwork.freedesktop.org/patch/msgid/20230324164226.256084-2-mcanal@igalia.com
