Le 18/07/2025 à 15:03, Marius Vlad a écrit :
Hi,
FWIW, we (Weston) also use vkms in CI and we have in plan to make use of
these changes to exercise some internal code paths and enhance our tests.
Look forward to getting these into the tree and have it a in release. We
tend to follow with a branch/stable release so I suppose that's going be
a while. Just wanted to also say thanks a lot for driving this.
Hi,
Thanks a lot for this positive feedback!
Just curios, in the current form would it be possible to configure the
plane's zpos position? Apart from testing underlay/overlay in the same
time, some drivers today allows the primary to be independently
positioned. Simulating these type of configurations would allow see what
architectural changes we might need to do to transition towards a place
where we can use any other plane as a (fallback) compositing one like we
do today with the primary one.
Currently nothing is done to do a proper z-pos managment, and even
worse: the z-order is not really predictable (order of creation in
configfs, so if userspace creates cursor-primary, the cursor will be
behind the primary plane).
We need to change this before merging ConfigFS. Fir the first iteration,
we can simply: make primary plane always at the back (zpos=0), overlay
with undefined ordering (zpos=1), cursor on top (zpos=2) directly in
vkms_plane_init. I need to check if this will be a uAPI break if we add
later some configfs attributes like default_zpos / zpos_min / zpos_max.
Even with this, we need to fix [1] to compose planes in the correct
order (I don't think this is broken right now because we create primary
then overlays then cursor, so the composition order will be correct).
[1]:https://elixir.bootlin.com/linux/v6.15.6/source/drivers/gpu/drm/vkms/vkms_composer.c#L392-L394
@José, I will fix the vkms_composer to use plane->state->zpos or
normalized_zpos.
Thanks a lot for this suggestion which showed a flaw in the current
implementation!
Louis Chauvet
On Thu, Jul 17, 2025 at 06:37:17PM +0200, Louis Chauvet wrote:
+CC: Mark (Google), Sebastian (Mutter), Xaver (KWin), Victoria (Cosmic)
Hi everyone,
Last week, I presented this work at the Display Next Hackfest, and the
feedback from compositors was very positive. At least KWin, Mutter, and
Cosmic are interested in integrating it into their tests, so it would be
great if someone could review it.
Sebastian quickly tested this work (using [2] for full features) with their
existing VKMS tests [1], and it worked. From what I understand, the tests
are quite basic —just sanity checks— but we were able to reproduce the
default vkms device using ConfigFS.
If another compositor wants to test the ConfigFS interface (I will try to
keep [2] updated), that would be amazing. Feel free to send feedback!
A small note: This series has a minor conflict since the conversion to the
faux device, but it can be applied using `b4 am -3 ... && git am -3 ...`.
@josé, if you send a new iteration, can you add markyac...@google.com in
copy, and maybe Sebastian, Xaver, Victoria if they want to follow the
upstreaming?
Thank you,
Louis Chauvet
[1]:https://gitlab.gnome.org/swick/mutter/-/commit/88a7354942d9728dae06fb83cc4f2d2c7b08b694
[2]:https://github.com/Fomys/linux/tree/configfs-everything
Le 07/05/2025 à 15:54, José Expósito a écrit :
Hi everyone,
This series allow to configure one or more VKMS instances without having
to reload the driver using configfs.
The series is structured in 3 blocks:
- Patches 1..11: Basic device configuration. For simplicity, I kept the
available options as minimal as possible.
- Patches 12 and 13: New option to skip the default device creation and
to-do
cleanup.
- Patches 14, 15 and 16: Allow to hot-plug and unplug connectors. This is
not
part of the minimal set of options, but I included in this series so it
can
be used as a template/example of how new configurations can be added.
The process of configuring a VKMS device is documented in "vkms.rst".
Finally, the code is thoroughly tested by a collection of IGT tests [1].
Best wishes,
José Expósito
[1] https://lists.freedesktop.org/archives/igt-dev/2025-February/086071.html
Changes in v5:
- Added Reviewed-by tags, thanks Louis!
- Rebased on top of drm-misc-next
- Link to v4:
https://lore.kernel.org/dri-devel/20250407081425.6420-1-jose.exposit...@gmail.com/
Changes in v4:
- Since Louis and I worked on this together, set him as the author of some
of
the patches and me as co-developed-by to reflect this joint effort.
- Rebased on top of drm-misc-next
- Link to v3:
https://lore.kernel.org/all/20250307163353.5896-1-jose.exposit...@gmail.com/
Changes in v3:
- Applied review comments by Louis Chauvet: (thanks!!)
- Use scoped_guard() instead of guard(mutex)(...)
- Fix a use-after-free error in the connector hot-plug code
- Rebased on top of drm-misc-next
- Link to v2:
https://lore.kernel.org/all/20250225175936.7223-1-jose.exposit...@gmail.com/
Changes in v2:
- Applied review comments by Louis Chauvet:
- Use guard(mutex)(...) instead of lock/unlock
- Return -EBUSY when trying to modify a enabled device
- Move the connector hot-plug related patches to the end
- Rebased on top of drm-misc-next
- Link to v1:
https://lore.kernel.org/dri-devel/20250218170808.9507-1-jose.exposit...@gmail.com/T/
José Expósito (6):
drm/vkms: Expose device creation and destruction
drm/vkms: Allow to configure the default device creation
drm/vkms: Remove completed task from the TODO list
drm/vkms: Allow to configure connector status
drm/vkms: Allow to update the connector status
drm/vkms: Allow to configure connector status via configfs
Louis Chauvet (10):
drm/vkms: Add and remove VKMS instances via configfs
drm/vkms: Allow to configure multiple planes via configfs
drm/vkms: Allow to configure the plane type via configfs
drm/vkms: Allow to configure multiple CRTCs via configfs
drm/vkms: Allow to configure CRTC writeback support via configfs
drm/vkms: Allow to attach planes and CRTCs via configfs
drm/vkms: Allow to configure multiple encoders via configfs
drm/vkms: Allow to attach encoders and CRTCs via configfs
drm/vkms: Allow to configure multiple connectors via configfs
drm/vkms: Allow to attach connectors and encoders via configfs
Documentation/gpu/vkms.rst | 100 ++-
drivers/gpu/drm/vkms/Kconfig | 1 +
drivers/gpu/drm/vkms/Makefile | 3 +-
drivers/gpu/drm/vkms/tests/vkms_config_test.c | 24 +
drivers/gpu/drm/vkms/vkms_config.c | 8 +-
drivers/gpu/drm/vkms/vkms_config.h | 26 +
drivers/gpu/drm/vkms/vkms_configfs.c | 833 ++++++++++++++++++
drivers/gpu/drm/vkms/vkms_configfs.h | 8 +
drivers/gpu/drm/vkms/vkms_connector.c | 35 +
drivers/gpu/drm/vkms/vkms_connector.h | 9 +
drivers/gpu/drm/vkms/vkms_drv.c | 18 +-
drivers/gpu/drm/vkms/vkms_drv.h | 20 +
12 files changed, 1072 insertions(+), 13 deletions(-)
create mode 100644 drivers/gpu/drm/vkms/vkms_configfs.c
create mode 100644 drivers/gpu/drm/vkms/vkms_configfs.h
base-commit: a6c0a91ccb257eaec2aee080df06863ce7601315
--
Louis Chauvet, Bootlin
Embedded Linux and Kernel engineering
https://bootlin.com
--
Louis Chauvet, Bootlin
Embedded Linux and Kernel engineering
https://bootlin.com
