Intro
=====
At long last, we're back!
This patchset adds basic ConfigFS support to VKMS, allowing users to
build new DRM devices with user-defined DRM objects and object
relationships by creating, writing, and symlinking files.
Usage
=====
After installing these patches, you can create a VKMS device with two
displays and a movable overlay like so (this is documented in the
patches):
$ modprobe vkms enable_overlay=1 enable_cursor=1 enable_writeback=1
$ mkdir -p /config/
$ mount -t configfs none /config
$ export DRM_PLANE_TYPE_PRIMARY=1
$ export DRM_PLANE_TYPE_CURSOR=2
$ export DRM_PLANE_TYPE_OVERLAY=0
$ mkdir /config/vkms/test
$ mkdir /config/vkms/test/planes/primary
$ echo $DRM_PLANE_TYPE_PRIMARY > /config/vkms/test/planes/primary/type
$ mkdir /config/vkms/test/planes/other_primary
$ echo $DRM_PLANE_TYPE_PRIMARY > /config/vkms/test/planes/other_primary/type
$ mkdir /config/vkms/test/planes/cursor
$ echo $DRM_PLANE_TYPE_CURSOR > /config/vkms/test/planes/cursor/type
$ mkdir /config/vkms/test/planes/overlay
$ echo $DRM_PLANE_TYPE_OVERLAY > /config/vkms/test/planes/overlay/type
$ mkdir /config/vkms/test/crtcs/crtc
$ mkdir /config/vkms/test/crtcs/crtc_other
$ mkdir /config/vkms/test/encoders/encoder
$ mkdir /config/vkms/test/connectors/connector
$ ln -s /config/vkms/test/encoders/encoder /config/vkms/test/connectors/connector/possible_encoders
$ ln -s /config/vkms/test/crtcs/crtc /config/vkms/test/encoders/encoder/possible_crtcs/
$ ln -s /config/vkms/test/crtcs/crtc /config/vkms/test/planes/primary/possible_crtcs/
$ ln -s /config/vkms/test/crtcs/crtc /config/vkms/test/planes/cursor/possible_crtcs/
$ ln -s /config/vkms/test/crtcs/crtc /config/vkms/test/planes/overlay/possible_crtcs/
$ ln -s /config/vkms/test/crtcs/crtc_other /config/vkms/test/planes/overlay/possible_crtcs/
$ ln -s /config/vkms/test/crtcs/crtc_other /config/vkms/test/planes/other_primary/possible_crtcs/
$ echo 1 > /config/vkms/test/enabled
Changes within core VKMS
========================
This introduces a few important changes to the overall structure of
VKMS:
- Devices are now memory managed!
- Support for multiple CRTCs and other objects has been added
Since v1
========
- Added DRMM memory management to automatically clean up resources
- Added a param to disable the default device
- Renamed "cards" to "devices" to improve legibility
- Added a lock for the configfs setup handler
- Moved all the new docs into the relevant .c file
- Addressed as many of sean@xxxxxxxxxx as possible
Testing
=======
- New IGT tests (see
gitlab.freedesktop.org/jshargo/igt-gpu-tools/-/merge_requests/1)
- Existing IGT tests (excluding .*suspend.*, including .*kms_flip.*
.*kms_writeback.* .*kms_cursor_crc.*, .*kms_plane.*)
Outro
=====
I'm excited to share these changes, it's my still my first kernel patch
and I've been putting a lot of love into these.
Jim Shargo (6):
drm/vkms: Back VKMS with DRM memory management instead of static
objects
drm/vkms: Support multiple DRM objects (crtcs, etc.) per VKMS device
drm/vkms: Provide platform data when creating VKMS devices
drm/vkms: Add ConfigFS scaffolding to VKMS
drm/vkms: Support enabling ConfigFS devices
drm/vkms: Add a module param to enable/disable the default device
Documentation/gpu/vkms.rst | 17 +-
drivers/gpu/drm/Kconfig | 1 +
drivers/gpu/drm/vkms/Makefile | 1 +
drivers/gpu/drm/vkms/vkms_composer.c | 28 +-
drivers/gpu/drm/vkms/vkms_configfs.c | 657 ++++++++++++++++++++++++++
drivers/gpu/drm/vkms/vkms_crtc.c | 97 ++--
drivers/gpu/drm/vkms/vkms_drv.c | 208 +++++---
drivers/gpu/drm/vkms/vkms_drv.h | 166 +++++--
drivers/gpu/drm/vkms/vkms_output.c | 299 ++++++++++--
drivers/gpu/drm/vkms/vkms_plane.c | 44 +-
drivers/gpu/drm/vkms/vkms_writeback.c | 26 +-
11 files changed, 1312 insertions(+), 232 deletions(-)
create mode 100644 drivers/gpu/drm/vkms/vkms_configfs.c
--
2.41.0.162.gfafddb0af9-goog
