drm/vkms: Avoid reading beyond LUT array

When the floor LUT index (drm_fixp2int(lut_index) is the last
index of the array the ceil LUT index will point to an entry
beyond the array. Make sure we guard against it and use the
value of the floor LUT index.

v3:
- Drop bits from commit description that didn't contribute
anything of value

Fixes: db1f254f2cfa ("drm/vkms: Add support to 1D gamma LUT")
Signed-off-by: Harry Wentland <harry.wentland@amd.com>
Cc: Arthur Grillo <arthurgrillo@riseup.net>
Reviewed-by: Arthur Grillo <arthurgrillo@riseup.net>
Reviewed-by: Melissa Wen <mwen@igalia.com>
Signed-off-by: Melissa Wen <melissa.srw@gmail.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20231108163647.106853-6-harry.wentland@amd.com

Revert "drm/vkms: Fix race-condition between the hrtimer and the atomic commit"

This reverts commit a0e6a017ab56936c0405fe914a793b241ed25ee0.

Unlocking a mutex in the context of a hrtimer callback is violating mutex
locking rules, as mutex_unlock() from interrupt context is not permitted.

Link: https://lore.kernel.org/dri-devel/ZQLAc%2FFwkv%2FGiVoK@phenom.ffwll.local/T/#t
Acked-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Maíra Canal <mcanal@igalia.com>
Signed-off-by: Maíra Canal <mairacanal@riseup.net>
Link: https://patchwork.freedesktop.org/patch/msgid/20230914102024.1789154-1-mcanal@igalia.com

drm/vkms: Fix race-condition between the hrtimer and the atomic commit

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

drm/vkms: Add support to 1D gamma LUT

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

drm/vkms: Isolate writeback pixel conversion functions

All convertions from the ARGB16161616 format follow the same structure.
Instead of repeting the same structure for each supported format, create
a function to encapsulate the common logic and isolate the pixel
conversion functions in a callback function.

Suggested-by: Melissa Wen <mwen@igalia.com>
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/20230515135204.115393-4-mcanal@igalia.com

drm/vkms: Fix all kernel-doc warnings of the vkms_composer file

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

drm/vkms: add rotate-270 property

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

drm/vkms: add rotate-90 property

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

drm/vkms: add reflect-y and rotate-180 property

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

drm/vkms: add rotate-0 and reflect-x property

Currently, vkms doesn't support any reflection property. Therefore, add
the reflect-x property to vkms through a software implementation of the
operation. This is possible by reverse reading the x axis during the
blending.

Tested with igt@kms_rotation_crc@primary-reflect-x [1] and
igt@kms_rotation_crc@sprite-reflect-x [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/20230418130525.128733-3-mcanal@igalia.com

drm/vkms: isolate pixel conversion functionality

Currently, the pixel conversion functions repeat the same loop to
iterate the rows. Instead of repeating the same code for each pixel
format, create a function to wrap the loop and isolate the pixel
conversion functionality.

Suggested-by: Arthur Grillo <arthurgrillo@riseup.net>
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/20230418130525.128733-2-mcanal@igalia.com

drm: vkms: Supports to the case where primary plane doesn't match the CRTC

We will remove the current assumption that the primary plane has the
same size and position as CRTC and that the primary plane is the
bottom-most in zpos order, or is even enabled. At least as far
as the blending machinery is concerned.

For that we will add CRTC dimension information to `vkms_crtc_state`
and add a opaque black backgound color.

Because now we need to fill the background, we had a loss in
performance with this change. Results running the IGT[1] test
`igt@kms_cursor_crc@pipe-a-cursor-512x512-onscreen` ten times:

| Frametime |
|:--------------------------------------------:|
| Implementation | Previous | This commit |
|:---------------:|:---------:|:--------------:|
| frametime range | 5~18 ms | 10~22 ms |
| Average | 8.47 ms | 12.32 ms |

[1] IGT commit id: bc3f6833a12221a46659535dac06ebb312490eb4

V6: Improve the commit description (Pekka Paalanen).
Update some comments (Pekka Paalanen).
Remove some fields from `vkms_crtc_state` and move where
some variables are set (Pekka Paalanen).

Reviewed-by: Melissa Wen <mwen@igalia.com>
Signed-off-by: Igor Torrente <igormtorrente@gmail.com>
Signed-off-by: Melissa Wen <melissa.srw@gmail.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20220905190811.25024-8-igormtorrente@gmail.com

drm: vkms: Refactor the plane composer to accept new formats

Currently the blend function only accepts XRGB_8888 and ARGB_8888
as a color input.

This patch refactors all the functions related to the plane composition
to overcome this limitation.

The pixels blend is done using the new internal format. And new handlers
are being added to convert a specific format to/from this internal format.

So the blend operation depends on these handlers to convert to this common
format. The blended result, if necessary, is converted to the writeback
buffer format.

This patch introduces three major differences to the blend function.
1 - All the planes are blended at once.
2 - The blend calculus is done as per line instead of per pixel.
3 - It is responsible to calculates the CRC and writing the writeback
buffer(if necessary).

These changes allow us to allocate way less memory in the intermediate
buffer to compute these operations. Because now we don't need to
have the entire intermediate image lines at once, just one line is
enough.

| Memory consumption (output dimensions) |
|:--------------------------------------:|
| Current | This patch |
|:------------------:|:-----------------:|
| Width * Heigth | 2 * Width |

Beyond memory, we also have a minor performance benefit from all
these changes. Results running the IGT[1] test
`igt@kms_cursor_crc@pipe-a-cursor-512x512-onscreen` ten times:

| Frametime |
|:------------------------------------------:|
| Implementation | Current | This commit |
|:---------------:|:---------:|:------------:|
| frametime range | 9~22 ms | 5~17 ms |
| Average | 11.4 ms | 7.8 ms |

[1] IGT commit id: bc3f6833a12221a46659535dac06ebb312490eb4

V2: Improves the performance drastically, by performing the operations
per-line and not per-pixel(Pekka Paalanen).
Minor improvements(Pekka Paalanen).
V3: Changes the code to blend the planes all at once. This improves
performance, memory consumption, and removes much of the weirdness
of the V2(Pekka Paalanen and me).
Minor improvements(Pekka Paalanen and me).
V4: Rebase the code and adapt it to the new NUM_OVERLAY_PLANES constant.
V5: Minor checkpatch fixes and the removal of TO-DO item(Melissa Wen).
Several security/robustness improvents(Pekka Paalanen).
Removes check_planes_x_bounds function and allows partial
partly off-screen(Pekka Paalanen).
V6: Fix a mismatch of some variable sizes (Pekka Paalanen).
Several minor improvements (Pekka Paalanen).

Reviewed-by: Melissa Wen <mwen@igalia.com>
Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Igor Torrente <igormtorrente@gmail.com>
Signed-off-by: Melissa Wen <melissa.srw@gmail.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20220905190811.25024-7-igormtorrente@gmail.com

drm: vkms: get the reference to `drm_framebuffer` instead if coping it

Instead of coping `drm_framebuffer` - which can cause problems -
we just get the reference and add the ref count.

Reviewed-by: Melissa Wen <mwen@igalia.com>
Signed-off-by: Igor Torrente <igormtorrente@gmail.com>
Signed-off-by: Melissa Wen <melissa.srw@gmail.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20220905190811.25024-5-igormtorrente@gmail.com

drm: vkms: Rename `vkms_composer` to `vkms_frame_info`

Changes the name of this struct to a more meaningful name.
A name that represents better what this struct is about.

Composer is the code that do the compositing of the planes.
This struct contains information on the frame used in the output
composition. Thus, vkms_frame_info is a better name to represent
this.

V5: Fix a commit message typo(Melissa Wen).
V6: Fix wrong iosys_map_is_null verification at compose_plane
(Melissa Wen).

Reviewed-by: Melissa Wen <mwen@igalia.com>
Signed-off-by: Igor Torrente <igormtorrente@gmail.com>
Signed-off-by: Melissa Wen <melissa.srw@gmail.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20220905190811.25024-3-igormtorrente@gmail.com

drm: vkms: Alloc the compose frame using vzalloc

Currently, the memory to the composition frame is being allocated using
the kzmalloc. This comes with the limitation of maximum size of one
page size(which in the x86_64 is 4Kb and 4MB for default and hugepage
respectively).

Somes test of igt (e.g. kms_plane@pixel-format) uses more than 4MB when
testing some pixel formats like ARGB16161616 and the following error were
showing up when running kms_plane@plane-panning-bottom-right*:

[drm:vkms_composer_worker [vkms]] *ERROR* Cannot allocate memory for
output frame.

This problem is addessed by allocating the memory using kvzalloc that
circunvents this limitation.

V5: Improve the commit message and drop the debugging issues in VKMS
TO-DO(Melissa Wen).

Reviewed-by: Melissa Wen <mwen@igalia.com>
Signed-off-by: Igor Torrente <igormtorrente@gmail.com>
Signed-off-by: Melissa Wen <melissa.srw@gmail.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20220404204515.42144-2-igormtorrente@gmail.com

drm/vkms: check plane_composer->map[0] before using it

Fix a copypasta error. The caller of compose_plane() already checks
primary_composer->map. In contrast, plane_composer->map is never
verified here before handling.

Fixes: 7938f4218168 ("dma-buf-map: Rename to iosys-map")
Reviewed-by: André Almeida <andrealmeid@riseup.net>
Signed-off-by: Tales Lelo da Aparecida <tales.aparecida@gmail.com>
Signed-off-by: Melissa Wen <melissa.srw@gmail.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20220415111300.61013-2-tales.aparecida@gmail.com

drm/vkms: Update vkms_composer_worker documentation

Since commit ba420afab565 ("drm/vkms: Bugfix racing hrtimer vblank
handle") the work is scheduled at vkms_vblank_simulate() and since
commit 5ef8100a3919 ("drm/vkms: flush crc workers earlier in commit
flow") the work is flushed at vkms_atomic_commit_tail(). Update function
commment to reflect that.

Signed-off-by: André Almeida <andrealmeid@igalia.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/20220521191342.23520-1-andrealmeid@igalia.com

dma-buf-map: Rename to iosys-map

Rename struct dma_buf_map to struct iosys_map and corresponding APIs.
Over time dma-buf-map grew up to more functionality than the one used by
dma-buf: in fact it's just a shim layer to abstract system memory, that
can be accessed via regular load and store, from IO memory that needs to
be acessed via arch helpers.

The idea is to extend this API so it can fulfill other needs, internal
to a single driver. Example: in the i915 driver it's desired to share
the implementation for integrated graphics, which uses mostly system
memory, with discrete graphics, which may need to access IO memory.

The conversion was mostly done with the following semantic patch:

@r1@
@@
- struct dma_buf_map
+ struct iosys_map

@r2@
@@
(
- DMA_BUF_MAP_INIT_VADDR
+ IOSYS_MAP_INIT_VADDR
|
- dma_buf_map_set_vaddr
+ iosys_map_set_vaddr
|
- dma_buf_map_set_vaddr_iomem
+ iosys_map_set_vaddr_iomem
|
- dma_buf_map_is_equal
+ iosys_map_is_equal
|
- dma_buf_map_is_null
+ iosys_map_is_null
|
- dma_buf_map_is_set
+ iosys_map_is_set
|
- dma_buf_map_clear
+ iosys_map_clear
|
- dma_buf_map_memcpy_to
+ iosys_map_memcpy_to
|
- dma_buf_map_incr
+ iosys_map_incr
)

@@
@@
- #include <linux/dma-buf-map.h>
+ #include <linux/iosys-map.h>

Then some files had their includes adjusted and some comments were
update to remove mentions to dma-buf-map.

Since this is not specific to dma-buf anymore, move the documentation to
the "Bus-Independent Device Accesses" section.

v2:
- Squash patches

v3:
- Fix wrong removal of dma-buf.h from MAINTAINERS
- Move documentation from dma-buf.rst to device-io.rst

v4:
- Change documentation title and level

Signed-off-by: Lucas De Marchi <lucas.demarchi@intel.com>
Acked-by: Christian König <christian.koenig@amd.com>
Acked-by: Sumit Semwal <sumit.semwal@linaro.org>
Acked-by: Thomas Zimmermann <tzimmermann@suse.de>
Link: https://patchwork.freedesktop.org/patch/msgid/20220204170541.829227-1-lucas.demarchi@intel.com

drm/vkms: Use offset-adjusted shadow-plane mappings and output

For framebuffers with non-zero offset fields, shadow-plane helpers
provide a pointer to the first byte of the contained data. Use it in
vkms.

Also provide use the offset-adjusted data address for the writeback
job's output buffers. Output framebuffers with non-zero offsets now
have their content written to the correct location.

Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Acked-by: Sam Ravnborg <sam@ravnborg.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20210803125928.27780-12-tzimmermann@suse.de

drm/vkms: Map output framebuffer BOs with drm_gem_fb_vmap()

Abstract the framebuffer details by mappings its BOs with a call
to drm_gem_fb_vmap(). Unmap with drm_gem_fb_vunamp().

Before, the output address with stored as raw pointer in the priv
field of struct drm_writeback_job. Introduce the new type
struct vkms_writeback_job, which holds the output mappings addresses
while the writeback job is active.

The patchset also cleans up some internal casting an setup of the
output addresses. No functional changes.

v3:
* free instances of struct vkms_writeback_job on cleanup
or errors

Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: Rodrigo Siqueira <Rodrigo.Siqueira@amd.com>
Acked-by: Sam Ravnborg <sam@ravnborg.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20210730183511.20080-6-tzimmermann@suse.de

drm/vkms: Use dma-buf mapping from shadow-plane state for composing

Store the shadow-buffer mapping's address in struct vkms_composer and
use the value when composing the output. It's the same value as stored
in the GEM SHMEM BO, but frees the composer code from its dependency
on GEM SHMEM.

Using struct dma_buf_map is how framebuffer access is supposed to be.
The long-term plan is to perform all framebuffer access via struct
dma_buf_map and avoid the details of accessing I/O and system memory.

Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: Melissa Wen <melissa.srw@gmail.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20210705074633.9425-5-tzimmermann@suse.de

drm/vkms: Inherit plane state from struct drm_shadow_plane_state

Subclass struct drm_shadow_plane_state for VKMS planes and update
all plane-state callbacks accordingly.

Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: Melissa Wen <melissa.srw@gmail.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20210705074633.9425-3-tzimmermann@suse.de

drm/vkms: add overlay support

Add support to overlay plane, in addition to primary and cursor
planes. In this approach, the plane composition still requires an
active primary plane and planes are composed associatively in the
order: (primary <- overlay) <- cursor

It enables to run the following IGT tests successfully:
- kms_plane_cursor:
- pipe-A-[overlay, primary, viewport]-size-[64, 128, 256]
- kms_atomic:
- plane-overlay-legacy
and preserves the successful execution of kms_cursor_crc,
kms_writeback and kms_flip

Signed-off-by: Melissa Wen <melissa.srw@gmail.com>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/8261bf93d8a0e3ffaf81d8e7c9b3e9c229116be3.1619250933.git.melissa.srw@gmail.com

drm/vkms: add XRGB planes composition

Add support for composing XRGB888 planes in addition to the ARGB8888
format. In the case of an XRGB plane at the top, the composition consists
of copying the RGB values of a pixel from src to dst and clearing alpha
channel, without the need for alpha blending operations for each pixel.

Blend equations assume a completely opaque background, i.e., primary plane
is not cleared before pixel blending but alpha channel is explicitly
opaque (a = 0xff). Also, there is room for performance evaluation in
switching pixel blend operation according to the plane format.

v4:
- clear alpha channel (0xff) after blend color values by pixel
- improve comments on blend ops to reflect the current state
- describe in the commit message future improvements for plane composition

Signed-off-by: Melissa Wen <melissa.srw@gmail.com>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/07bcf4643d11da9480599fe1b165e478bff58b25.1619250933.git.melissa.srw@gmail.com

drm/vkms: rename cursor to plane on ops of planes composition

Generalize variables and function names used for planes composition
(from cursor to plane), since we will reuse the operations for both
cursor and overlay types.

No functional change.

v4:
- use better names for functions of plane composition (Daniel)

Signed-off-by: Melissa Wen <melissa.srw@gmail.com>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/ef3249c9ac3a08b7079894f9f1ccf70960194ec7.1619250933.git.melissa.srw@gmail.com

drm/vkms: Switch to shmem helpers

Inspired by a patch by Chris Wilson for vgem. Plus this gives us vmap
at the gem bo level, which we need for generic fbdev emulation.

Luckily shmem also tracks ->vaddr, so we just need to adjust the code
all over a bit to make this fit.

Also wire up handle_to_fd, dunno why that was missing.

v2:
- Drop now unused container_of #define (Melissa)
- Make sure we keep creating cached objects, this is for testing
(Thomas)

Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Cc: Maxime Ripard <mripard@kernel.org>
Cc: Thomas Zimmermann <tzimmermann@suse.de>
Cc: David Airlie <airlied@linux.ie>
Cc: Daniel Vetter <daniel@ffwll.ch>
Cc: Rodrigo Siqueira <rodrigosiqueiramelo@gmail.com>
Cc: Melissa Wen <melissa.srw@gmail.com>
Cc: Haneen Mohammed <hamohammed.sa@gmail.com>
Acked-by: Thomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: Melissa Wen <melissa.srw@gmail.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20201013111027.375999-1-daniel.vetter@ffwll.ch

drm/vkms: Add support for writeback

This patch implements the necessary functions to add writeback support
for vkms. This feature is useful for testing compositors if you don't
have hardware with writeback support.

Change in V4 (Emil and Melissa):
- Move signal completion above drm_crtc_add_crc_entry()
- Make writeback always available
- Use appropriate namespace
- Drop fb check in vkms_wb_atomic_commit
- Make vkms_set_composer visible for writeback code
- Enable composer operation on prepare_job and disable it on cleanup_job
- Drop extra space at the end of the file
- Rebase

Change in V3 (Daniel):
- If writeback is enabled, compose everything into the writeback buffer
instead of CRC private buffer
- Guarantees that the CRC will match exactly what we have in the
writeback buffer.

Change in V2:
- Rework signal completion (Brian)
- Integrates writeback with active_planes (Daniel)
- Compose cursor (Daniel)

Signed-off-by: Rodrigo Siqueira <rodrigosiqueiramelo@gmail.com>
Reviewed-by: Liviu Dudau <liviu.dudau@arm.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200830142000.146706-4-rodrigosiqueiramelo@gmail.com

drm/vkms: Compute CRC without change input data

This commit decouples pixel manipulation from compute_crc() for avoiding
any pixel change during the CRC calculation. This commits represents a
preparation work for making VKMS able to support the writeback feature.

Change in V5 (Melissa):
- Rebase and drop bitmap for alpha
Change in V4 (Emil):
- Move bitmap_clear operation and comments to get_pixel function

Signed-off-by: Rodrigo Siqueira <rodrigosiqueiramelo@gmail.com>
Reviewed-by: Melissa Wen <melissa.srw@gmail.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200830142000.146706-3-rodrigosiqueiramelo@gmail.com

drm/vkms: Decouple crc operations from composer

In the vkms_composer.c, some of the functions related to CRC and compose
have interdependence between each other. This patch reworks some
functions inside vkms_composer to make crc and composer computation
decoupled.

This patch is preparation work for making vkms able to support new
features.

Tested-by: Melissa Wen <melissa.srw@gmail.com>
Signed-off-by: Rodrigo Siqueira <rodrigosiqueiramelo@gmail.com>
Reviewed-by: Melissa Wen <melissa.srw@gmail.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200830142000.146706-2-rodrigosiqueiramelo@gmail.com

drm/vkms: add alpha-premultiplied color blending

The VKMS blend function was ignoring the alpha channel and just
overwriting vaddr_src with vaddr_dst. This XRGB approach triggers a
warning when running the kms_cursor_crc/cursor-alpha-transparent test
case. In IGT, cairo_format_argb32 uses premultiplied alpha (according to
documentation). Also current DRM assumption is that alpha is
premultiplied. Therefore, this patch considers premultiplied alpha
blending eq to compose vaddr_src with vaddr_dst.

This change removes the following cursor-alpha-transparent warning:

"Suspicious CRC: All values are 0."

V2:
- static for local functions
- const for the read-only variable argb_src
- replaces variable names
- drops unnecessary comment

Cc: Daniel Vetter <daniel@ffwll.ch>
Cc: Rodrigo Siqueira <rodrigosiqueiramelo@gmail.com>
Cc: Haneen Mohammed <hamohammed.sa@gmail.com>
Signed-off-by: Melissa Wen <melissa.srw@gmail.com>
Reviewed-by: Rodrigo Siqueira <rodrigosiqueiramelo@gmail.com>
Signed-off-by: Rodrigo Siqueira <rodrigosiqueiramelo@gmail.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200825114532.abzdooluny2ekzvm@smtp.gmail.com

drm/vkms: guarantee vblank when capturing crc

VKMS needs vblank interrupts enabled to capture CRC. When vblank is
disabled, tests like kms_cursor_crc and kms_pipe_crc_basic getting stuck
waiting for a capture that will not occur until vkms wakes up. This patch
adds a helper to set composer and ensure that vblank remains enabled as
long as the CRC capture is needed.

It clears the execution of the following kms_cursor_crc subtests:
1. pipe-A-cursor-[size,alpha-opaque, NxN-(on-screen, off-screen, sliding,
random, fast-moving])] - successful when running individually.
2. pipe-A-cursor-dpms passes again
3. pipe-A-cursor-suspend also passes

The issue was initially tracked in the sequential execution of IGT
kms_cursor_crc subtests: when running the test sequence or one of its
subtests twice, the odd execs complete and the pairs get stuck in an
endless wait. In the IGT code, calling a wait_for_vblank on preparing for
CRC capture prevented the busy-wait. But the problem persisted in the
pipe-A-cursor-dpms and -suspend subtests.

Checking the history, the pipe-A-cursor-dpms subtest was successful when,
in vkms_atomic_commit_tail, instead of using the flip_done op, it used
wait_for_vblanks. Another way to prevent blocking was wait_one_vblank when
enabling crtc. However, in both cases, pipe-A-cursor-suspend persisted
blocking in the 2nd start of CRC capture, which may indicate that
something got stuck in the step of CRC setup. Indeed, wait_one_vblank in
the crc setup was able to sync things and free all kms_cursor_crc
subtests. Besides, other alternatives to force enabling vblanks or prevent
disabling them such as calling drm_crtc_put_vblank or modeset_enables
before commit_planes + offdelay = 0, also unlock all subtests executions.

Finally, due to vkms's dependence on vblank interruptions to perform
tasks, this patch uses refcount to ensure that vblanks happen when
enabling composer and while crc capture is needed.

Cc: Rodrigo Siqueira <rodrigosiqueiramelo@gmail.com>
Cc: Haneen Mohammed <hamohammed.sa@gmail.com>

v2:
- extract a vkms_set_composer helper
- fix vblank refcounting for the disabling case

v3:
- make the vkms_set_composer helper static
- review the credit tags

Co-debugged-by: Sidong Yang <realwakka@gmail.com>
Signed-off-by: Sidong Yang <realwakka@gmail.com>
Signed-off-by: Melissa Wen <melissa.srw@gmail.com>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
[danvet: add changelog back in]
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/20200808120900.pudwwrfz44g3rqx7@smtp.gmail.com

drm/vkms: fix xrgb on compute crc

The previous memset operation was not correctly zeroing the alpha
channel to compute the crc, and as a result, the IGT subtest
kms_cursor_crc/pipe-A-cursor-alpha-transparent fails.

Fixes: db7f419c06d7c ("drm/vkms: Compute CRC with Cursor Plane")

Signed-off-by: Melissa Wen <melissa.srw@gmail.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/20200730202524.5upzuh4irboru7my@smtp.gmail.com

drm/vkms: Fix typo and preposion in function documentation

Fix typo in word 'blend' and in the word 'destination' and change
preposition 'at' to 'of' in function 'blend' documentation.
And change the task introduction word 'Todo' for the word all in uppercase
- 'TODO'. With the TODO word all in uppercase (as it's the standard) it's
easier to find the tasks that have to be done throughout the code.

Changes since V3:
Rodrigo:
- Merge the patch series into a single patch since it contains one single
logical change

Changes since V2:
- Add fix typo in word 'destination'
- Add change of the preposition
- Fix the name of the function in log message
- Add the change in word 'Todo'

Reviewed-by: Rodrigo Siqueira <rodrigosiqueiramelo@gmail.com>
Signed-off-by: Gabriela Bittencourt <gabrielabittencourt00@gmail.com>
Signed-off-by: Rodrigo Siqueira <Rodrigo.Siqueira@amd.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20191104161424.18105-1-gabrielabittencourt00@gmail.com

drm/vkms: drop use of drmP.h

Drop use of the deprecated drmP.h header.
Replace it with the necessary includes in the individual .c files.
The header files was self-contained, and extra includes were not added
there.

Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
Reviewed-by: Rodrigo Siqueira <rodrigosiqueiramelo@gmail.com>
Acked-by: Emil Velikov <emil.velikov@collabora.com>
Cc: Haneen Mohammed <hamohammed.sa@gmail.com>
Cc: Daniel Vetter <daniel@ffwll.ch>
Cc: David Airlie <airlied@linux.ie>
Link: https://patchwork.freedesktop.org/patch/msgid/20190630061922.7254-13-sam@ravnborg.org

drm/vkms: Rename vkms_crc.c into vkms_composer.c

As a preparation work for introducing writeback to vkms, this patch
renames the file vkms_crc.c into vkms_composer.c. Accordingly, it also
adjusts the functions and data structures to match the changes.

No functional change.

Signed-off-by: Rodrigo Siqueira <rodrigosiqueiramelo@gmail.com>
Acked-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/dea62063077ebf5cc1dfce8876e56788d15367e6.1561491964.git.rodrigosiqueiramelo@gmail.com