History log of /linux-6.15/Documentation/gpu/drivers.rst (Results 1 – 18 of 18)
Revision (<<< Hide revision tags) (Show revision tags >>>) Date Author Comments
Revision tags: v6.15, v6.15-rc7, v6.15-rc6, v6.15-rc5, v6.15-rc4, v6.15-rc3, v6.15-rc2, v6.15-rc1, v6.14, v6.14-rc7, v6.14-rc6
# b28786b1 06-Mar-2025 Danilo Krummrich <[email protected]>

gpu: nova-core: add initial documentation

Add the initial documentation of the Nova project.

The initial project documentation consists out of a brief introduction
of the project, as well as projec

gpu: nova-core: add initial documentation

Add the initial documentation of the Nova project.

The initial project documentation consists out of a brief introduction
of the project, as well as project guidelines both general and nova-core
specific and a task list for nova-core specifically.

The task list is divided into tasks for general Rust infrastructure
required by the project, tasks regarding GSP enablement and firmware
abstraction, general GPU driver tasks as well as tasks related to
external API design and test infrastructure.

Reviewed-by: Alexandre Courbot <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Danilo Krummrich <[email protected]>

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Revision tags: v6.14-rc5, v6.14-rc4, v6.14-rc3, v6.14-rc2, v6.14-rc1
# 22807d30 24-Jan-2025 Zhi Wang <[email protected]>

drm/nouveau: add a kernel doc to introduce the GSP RPC

In order to explain the name clean-ups in GSP RPC routines, a kernel
doc to explain the memory layout and terms is required.

Add a kernel doc

drm/nouveau: add a kernel doc to introduce the GSP RPC

In order to explain the name clean-ups in GSP RPC routines, a kernel
doc to explain the memory layout and terms is required.

Add a kernel doc to introduce the GSP RPC.

Cc: Danilo Krummrich <[email protected]>
Signed-off-by: Zhi Wang <[email protected]>
[ Fix bullet list indentation; add SPDX-License-Identifier. - Danilo ]
Signed-off-by: Danilo Krummrich <[email protected]>
Link: https://patchwork.freedesktop.org/patch/msgid/[email protected]

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Revision tags: v6.13, v6.13-rc7, v6.13-rc6, v6.13-rc5, v6.13-rc4, v6.13-rc3, v6.13-rc2, v6.13-rc1, v6.12, v6.12-rc7, v6.12-rc6, v6.12-rc5, v6.12-rc4, v6.12-rc3
# 904bc547 09-Oct-2024 Adrián Larumbe <[email protected]>

Documentation/gpu: Fix Panthor documentation build warnings

Fix Panthor documentation build errors uncovered by the makedocs target
when building with extra warnings enabled.

Signed-off-by: Adrián

Documentation/gpu: Fix Panthor documentation build warnings

Fix Panthor documentation build errors uncovered by the makedocs target
when building with extra warnings enabled.

Signed-off-by: Adrián Larumbe <[email protected]>
Fixes: 6a797bdfde77 ("drm/panthor: add sysfs knob for enabling job profiling")
Reported-by: Stephen Rothwell <[email protected]>
Reviewed-by: Steven Price <[email protected]>
Signed-off-by: Boris Brezillon <[email protected]>
Link: https://patchwork.freedesktop.org/patch/msgid/[email protected]

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Revision tags: v6.12-rc2, v6.12-rc1, v6.11, v6.11-rc7, v6.11-rc6, v6.11-rc5, v6.11-rc4, v6.11-rc3
# 28edaacb 09-Aug-2024 Sean Anderson <[email protected]>

drm: zynqmp_dp: Add debugfs interface for compliance testing

Add a debugfs interface for exercising the various test modes supported
by the DisplayPort controller. This allows performing compliance

drm: zynqmp_dp: Add debugfs interface for compliance testing

Add a debugfs interface for exercising the various test modes supported
by the DisplayPort controller. This allows performing compliance
testing, or performing signal integrity measurements on a failing link.
At the moment, we do not support sink-driven link quality testing,
although such support would be fairly easy to add.

Additionally, add some debugfs files for ignoring AUX errors and HPD
events, as this can allow testing with equipment that cannot emulate a
DPRX.

Signed-off-by: Sean Anderson <[email protected]>
[Tomi: fixed a few minor formatting issues]
Signed-off-by: Tomi Valkeinen <[email protected]>
Link: https://patchwork.freedesktop.org/patch/msgid/[email protected]

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Revision tags: v6.11-rc2, v6.11-rc1, v6.10, v6.10-rc7, v6.10-rc6, v6.10-rc5, v6.10-rc4, v6.10-rc3, v6.10-rc2, v6.10-rc1, v6.9, v6.9-rc7, v6.9-rc6, v6.9-rc5, v6.9-rc4, v6.9-rc3, v6.9-rc2, v6.9-rc1, v6.8, v6.8-rc7, v6.8-rc6, v6.8-rc5, v6.8-rc4, v6.8-rc3, v6.8-rc2, v6.8-rc1, v6.7, v6.7-rc8, v6.7-rc7, v6.7-rc6, v6.7-rc5, v6.7-rc4, v6.7-rc3, v6.7-rc2, v6.7-rc1, v6.6, v6.6-rc7, v6.6-rc6, v6.6-rc5, v6.6-rc4, v6.6-rc3, v6.6-rc2, v6.6-rc1, v6.5, v6.5-rc7, v6.5-rc6, v6.5-rc5, v6.5-rc4, v6.5-rc3, v6.5-rc2, v6.5-rc1, v6.4, v6.4-rc7, v6.4-rc6, v6.4-rc5, v6.4-rc4, v6.4-rc3, v6.4-rc2, v6.4-rc1, v6.3, v6.3-rc7, v6.3-rc6, v6.3-rc5
# dd08ebf6 30-Mar-2023 Matthew Brost <[email protected]>

drm/xe: Introduce a new DRM driver for Intel GPUs

Xe, is a new driver for Intel GPUs that supports both integrated and
discrete platforms starting with Tiger Lake (first Intel Xe Architecture).

The

drm/xe: Introduce a new DRM driver for Intel GPUs

Xe, is a new driver for Intel GPUs that supports both integrated and
discrete platforms starting with Tiger Lake (first Intel Xe Architecture).

The code is at a stage where it is already functional and has experimental
support for multiple platforms starting from Tiger Lake, with initial
support implemented in Mesa (for Iris and Anv, our OpenGL and Vulkan
drivers), as well as in NEO (for OpenCL and Level0).

The new Xe driver leverages a lot from i915.

As for display, the intent is to share the display code with the i915
driver so that there is maximum reuse there. But it is not added
in this patch.

This initial work is a collaboration of many people and unfortunately
the big squashed patch won't fully honor the proper credits. But let's
get some git quick stats so we can at least try to preserve some of the
credits:

Co-developed-by: Matthew Brost <[email protected]>
Co-developed-by: Matthew Auld <[email protected]>
Co-developed-by: Matt Roper <[email protected]>
Co-developed-by: Thomas Hellström <[email protected]>
Co-developed-by: Francois Dugast <[email protected]>
Co-developed-by: Lucas De Marchi <[email protected]>
Co-developed-by: Maarten Lankhorst <[email protected]>
Co-developed-by: Philippe Lecluse <[email protected]>
Co-developed-by: Nirmoy Das <[email protected]>
Co-developed-by: Jani Nikula <[email protected]>
Co-developed-by: José Roberto de Souza <[email protected]>
Co-developed-by: Rodrigo Vivi <[email protected]>
Co-developed-by: Dave Airlie <[email protected]>
Co-developed-by: Faith Ekstrand <[email protected]>
Co-developed-by: Daniel Vetter <[email protected]>
Co-developed-by: Mauro Carvalho Chehab <[email protected]>
Signed-off-by: Rodrigo Vivi <[email protected]>
Signed-off-by: Matthew Brost <[email protected]>

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# 815d8b04 22-Nov-2023 Sarah Walker <[email protected]>

drm/imagination: Add driver documentation

Add documentation for the UAPI.

Changes since v5:
- Remove obsolete VM documentation

Co-developed-by: Matt Coster <[email protected]>
Signed-off-by:

drm/imagination: Add driver documentation

Add documentation for the UAPI.

Changes since v5:
- Remove obsolete VM documentation

Co-developed-by: Matt Coster <[email protected]>
Signed-off-by: Matt Coster <[email protected]>
Co-developed-by: Donald Robson <[email protected]>
Signed-off-by: Donald Robson <[email protected]>
Signed-off-by: Sarah Walker <[email protected]>
Reviewed-by: Maxime Ripard <[email protected]>
Link: https://lore.kernel.org/r/76a7b18cfbe93066efcee3311ae795176ce7c65d.1700668843.git.donald.robson@imgtec.com
Signed-off-by: Maxime Ripard <[email protected]>

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# 8badbaff 05-Oct-2023 Adrián Larumbe <[email protected]>

Documentation/gpu: fix Panfrost documentation build warnings

Fix issues revealed by `make htmldocs` after adding Panfrost DRM
documentation file.

Signed-off-by: Adrián Larumbe <adrian.larumbe@colla

Documentation/gpu: fix Panfrost documentation build warnings

Fix issues revealed by `make htmldocs` after adding Panfrost DRM
documentation file.

Signed-off-by: Adrián Larumbe <[email protected]>
Fixes: f11b0417eec2 ("drm/panfrost: Add fdinfo support GPU load metrics")
Reported-by: kernel test robot <[email protected]>
Closes: https://lore.kernel.org/oe-kbuild-all/[email protected]
Reviewed-by: Steven Price <[email protected]>
Signed-off-by: Boris Brezillon <[email protected]>
Link: https://patchwork.freedesktop.org/patch/msgid/[email protected]

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Revision tags: v6.3-rc4, v6.3-rc3, v6.3-rc2, v6.3-rc1, v6.2, v6.2-rc8, v6.2-rc7, v6.2-rc6, v6.2-rc5, v6.2-rc4, v6.2-rc3, v6.2-rc2, v6.2-rc1, v6.1, v6.1-rc8, v6.1-rc7, v6.1-rc6, v6.1-rc5, v6.1-rc4, v6.1-rc3, v6.1-rc2, v6.1-rc1, v6.0, v6.0-rc7, v6.0-rc6, v6.0-rc5, v6.0-rc4, v6.0-rc3, v6.0-rc2, v6.0-rc1, v5.19, v5.19-rc8, v5.19-rc7, v5.19-rc6, v5.19-rc5, v5.19-rc4, v5.19-rc3, v5.19-rc2, v5.19-rc1, v5.18, v5.18-rc7, v5.18-rc6, v5.18-rc5, v5.18-rc4, v5.18-rc3, v5.18-rc2, v5.18-rc1, v5.17, v5.17-rc8, v5.17-rc7, v5.17-rc6, v5.17-rc5, v5.17-rc4, v5.17-rc3, v5.17-rc2, v5.17-rc1, v5.16, v5.16-rc8, v5.16-rc7, v5.16-rc6, v5.16-rc5, v5.16-rc4, v5.16-rc3
# e91f8401 25-Nov-2021 Rodrigo Siqueira <[email protected]>

Documentation/gpu: Reorganize DC documentation

Display core documentation is not well organized, and it is hard to find
information due to the lack of sections. This commit reorganizes the
documenta

Documentation/gpu: Reorganize DC documentation

Display core documentation is not well organized, and it is hard to find
information due to the lack of sections. This commit reorganizes the
documentation layout, and it is preparation work for future changes.

Changes since V1:
- Christian: Group amdgpu documentation together.
- Daniel: Drop redundant amdgpu prefix.
- Jani: Create index pages.
- Yann: Mirror display folder in the documentation.

Reviewed-by: Yann Dirson <[email protected]>
Reviewed-by: Harry Wentland <[email protected]>
Signed-off-by: Rodrigo Siqueira <[email protected]>
Signed-off-by: Alex Deucher <[email protected]>

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Revision tags: v5.16-rc2, v5.16-rc1, v5.15, v5.15-rc7, v5.15-rc6, v5.15-rc5, v5.15-rc4, v5.15-rc3, v5.15-rc2, v5.15-rc1, v5.14, v5.14-rc7, v5.14-rc6, v5.14-rc5, v5.14-rc4, v5.14-rc3, v5.14-rc2, v5.14-rc1, v5.13, v5.13-rc7, v5.13-rc6, v5.13-rc5, v5.13-rc4, v5.13-rc3, v5.13-rc2, v5.13-rc1, v5.12, v5.12-rc8, v5.12-rc7, v5.12-rc6, v5.12-rc5, v5.12-rc4, v5.12-rc3, v5.12-rc2, v5.12-rc1, v5.12-rc1-dontuse, v5.11, v5.11-rc7, v5.11-rc6, v5.11-rc5, v5.11-rc4, v5.11-rc3, v5.11-rc2, v5.11-rc1, v5.10, v5.10-rc7, v5.10-rc6, v5.10-rc5, v5.10-rc4, v5.10-rc3, v5.10-rc2, v5.10-rc1, v5.9, v5.9-rc8, v5.9-rc7, v5.9-rc6, v5.9-rc5, v5.9-rc4, v5.9-rc3, v5.9-rc2, v5.9-rc1, v5.8, v5.8-rc7, v5.8-rc6, v5.8-rc5, v5.8-rc4, v5.8-rc3, v5.8-rc2, v5.8-rc1, v5.7, v5.7-rc7, v5.7-rc6, v5.7-rc5, v5.7-rc4, v5.7-rc3, v5.7-rc2, v5.7-rc1, v5.6, v5.6-rc7, v5.6-rc6, v5.6-rc5, v5.6-rc4, v5.6-rc3, v5.6-rc2, v5.6-rc1, v5.5, v5.5-rc7, v5.5-rc6, v5.5-rc5, v5.5-rc4, v5.5-rc3, v5.5-rc2, v5.5-rc1, v5.4, v5.4-rc8, v5.4-rc7, v5.4-rc6, v5.4-rc5, v5.4-rc4, v5.4-rc3, v5.4-rc2, v5.4-rc1, v5.3, v5.3-rc8, v5.3-rc7, v5.3-rc6, v5.3-rc5, v5.3-rc4, v5.3-rc3, v5.3-rc2
# 174102f4 22-Jul-2019 Noralf Trønnes <[email protected]>

drm/tinydrm: Move mipi-dbi

This moves mipi-dbi to be a core helper with the name drm_mipi_dbi.

Fixup include's in drivers.
Move the docs entry and delete tinydrm.rst.
Delete the last tinydrm todo e

drm/tinydrm: Move mipi-dbi

This moves mipi-dbi to be a core helper with the name drm_mipi_dbi.

Fixup include's in drivers.
Move the docs entry and delete tinydrm.rst.
Delete the last tinydrm todo entry.

v2: Make DRM_MIPI_DBI tristate to enable it being built as a module.

Cc: Eric Anholt <[email protected]>
Cc: David Lechner <[email protected]>
Reviewed-by: Sam Ravnborg <[email protected]>
Signed-off-by: Noralf Trønnes <[email protected]>
Acked-by: David Lechner <[email protected]>
Acked-by: Eric Anholt <[email protected]>
Link: https://patchwork.freedesktop.org/patch/msgid/[email protected]

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Revision tags: v5.3-rc1, v5.2, v5.2-rc7, v5.2-rc6, v5.2-rc5, v5.2-rc4, v5.2-rc3, v5.2-rc2
# 5fc537bf 24-May-2019 Linus Walleij <[email protected]>

drm/mcde: Add new driver for ST-Ericsson MCDE

This adds a new DRM driver for the ST-Ericsson Multi Channel
Display Engine, MCDE display controller.

This hardware has three independent DSI hosts and

drm/mcde: Add new driver for ST-Ericsson MCDE

This adds a new DRM driver for the ST-Ericsson Multi Channel
Display Engine, MCDE display controller.

This hardware has three independent DSI hosts and can composit
and display several memory buffers onto an LCD display. It
was developed for several years inside of ST-Ericsson and
shipped with a few million mobile phones from Sony and Samsung,
as well as with the Snowball community development board.

The driver is currently pretty rudimentary but supports a
simple framebuffer so we can get penguins and graphics when
using these SoCs.

Acked-by: Daniel Vetter <[email protected]>
Signed-off-by: Linus Walleij <[email protected]>
Link: https://patchwork.freedesktop.org/patch/msgid/[email protected]

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Revision tags: v5.2-rc1, v5.1, v5.1-rc7, v5.1-rc6, v5.1-rc5, v5.1-rc4, v5.1-rc3, v5.1-rc2, v5.1-rc1, v5.0, v5.0-rc8, v5.0-rc7, v5.0-rc6, v5.0-rc5, v5.0-rc4, v5.0-rc3, v5.0-rc2, v5.0-rc1
# 557c3736 03-Jan-2019 james qian wang (Arm Technology China) <[email protected]>

drm/doc: Add initial komeda driver documentation

v2: Some editing changes according to Randy Dunlap's comments

Signed-off-by: James Qian Wang (Arm Technology China) <[email protected]>
Signed

drm/doc: Add initial komeda driver documentation

v2: Some editing changes according to Randy Dunlap's comments

Signed-off-by: James Qian Wang (Arm Technology China) <[email protected]>
Signed-off-by: Liviu Dudau <[email protected]>

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Revision tags: v4.20, v4.20-rc7, v4.20-rc6
# 3affaa5a 03-Dec-2018 Brian Starkey <[email protected]>

drm/afbc: Add AFBC modifier usage documentation

AFBC is a flexible, proprietary, lossless compression protocol and
format, with a number of defined DRM format modifiers. To facilitate
consistency an

drm/afbc: Add AFBC modifier usage documentation

AFBC is a flexible, proprietary, lossless compression protocol and
format, with a number of defined DRM format modifiers. To facilitate
consistency and compatibility between different AFBC producers and
consumers, document the expectations for usage of the AFBC DRM format
modifiers in a new .rst chapter.

Signed-off-by: Brian Starkey <[email protected]>
Reviewed-by: Liviu Dudau <[email protected]>
[Updated MAINTAINERS entry to show that "Mali DP Maintainers" is
actually a mailing list and added an SPDX-License-Identifier to
the documentation]
Signed-off-by: Liviu Dudau <[email protected]>

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Revision tags: v4.20-rc5, v4.20-rc4, v4.20-rc3, v4.20-rc2, v4.20-rc1, v4.19, v4.19-rc8, v4.19-rc7, v4.19-rc6, v4.19-rc5, v4.19-rc4
# b8592b48 14-Sep-2018 Leo Li <[email protected]>

drm/amd/display: Initial documentation for AMDgpu DC

[Why]
Documentation is helpful for the community to understand our code.
This change does some high-level documentation of some DM interfaces
wit

drm/amd/display: Initial documentation for AMDgpu DC

[Why]
Documentation is helpful for the community to understand our code.
This change does some high-level documentation of some DM interfaces
with DRM, and the amdgpu base driver.

[How]
An entry for AMDgpu DC has been added to Documentation/gpu/drivers.rst
TOC. amdgpu-dc.rst is created to pull in inline doc-strings, which:
- Provides an overview for "What is DM?"
- Documents AMDgpu DM lifecyle
- Documents IRQ management
- Documents atomic_check and commit_tail interfaces

Signed-off-by: Leo Li <[email protected]>
Reviewed-by: David Francis <[email protected]>
Acked-by: Leo Li <[email protected]>
Signed-off-by: Alex Deucher <[email protected]>

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Revision tags: v4.19-rc3
# ad9ff96f 07-Sep-2018 Haneen Mohammed <[email protected]>

drm/vkms: Add kerneldoc entry

Add an initial kerneldoc entry for vkms with a todo list.

Signed-off-by: Haneen Mohammed <[email protected]>
[danvet: Keep the todo.rst entry to point at the vkm

drm/vkms: Add kerneldoc entry

Add an initial kerneldoc entry for vkms with a todo list.

Signed-off-by: Haneen Mohammed <[email protected]>
[danvet: Keep the todo.rst entry to point at the vkms docs instead.]
Signed-off-by: Daniel Vetter <[email protected]>
Link: https://patchwork.freedesktop.org/patch/msgid/20180907174136.GA2648@haneenDRM

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Revision tags: v4.19-rc2, v4.19-rc1, v4.18, v4.18-rc8, v4.18-rc7, v4.18-rc6, v4.18-rc5, v4.18-rc4, v4.18-rc3, v4.18-rc2, v4.18-rc1, v4.17
# 99fa7ce3 29-May-2018 Michel Dänzer <[email protected]>

drm/doc: Add initial amdgpu driver documentation

Reviewed-by: Alex Deucher <[email protected]>
Signed-off-by: Michel Dänzer <[email protected]>
Signed-off-by: Alex Deucher <alexander.de

drm/doc: Add initial amdgpu driver documentation

Reviewed-by: Alex Deucher <[email protected]>
Signed-off-by: Michel Dänzer <[email protected]>
Signed-off-by: Alex Deucher <[email protected]>

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Revision tags: v4.17-rc7, v4.17-rc6, v4.17-rc5, v4.17-rc4
# 57692c94 30-Apr-2018 Eric Anholt <[email protected]>

drm/v3d: Introduce a new DRM driver for Broadcom V3D V3.x+

This driver will be used to support Mesa on the Broadcom 7268 and 7278
platforms.

V3D 3.3 introduces an MMU, which means we no longer need

drm/v3d: Introduce a new DRM driver for Broadcom V3D V3.x+

This driver will be used to support Mesa on the Broadcom 7268 and 7278
platforms.

V3D 3.3 introduces an MMU, which means we no longer need CMA or vc4's
complicated CL/shader validation scheme. This massively changes the
GEM behavior, so I've forked off to a new driver.

v2: Mark SUBMIT_CL as needing DRM_AUTH. coccinelle fixes from kbuild
test robot. Drop personal git link from MAINTAINERS. Don't
double-map dma-buf imported BOs. Add kerneldoc about needing MMU
eviction. Drop prime vmap/unmap stubs. Delay mmap offset setup
to mmap time. Use drm_dev_init instead of _alloc. Use
ktime_get() for wait_bo timeouts. Drop drm_can_sleep() usage,
since we don't modeset. Switch page tables back to WC (debug
change to coherent had slipped in). Switch
drm_gem_object_unreference_unlocked() to
drm_gem_object_put_unlocked(). Simplify overflow mem handling by
not sharing overflow mem between jobs.
v3: no changes
v4: align submit_cl to 64 bits (review by airlied), check zero flags in
other ioctls.

Signed-off-by: Eric Anholt <[email protected]>
Acked-by: Daniel Vetter <[email protected]> (v4)
Acked-by: Dave Airlie <[email protected]> (v3, requested submit_cl change)
Link: https://patchwork.freedesktop.org/patch/msgid/[email protected]

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Revision tags: v4.17-rc3, v4.17-rc2, v4.17-rc1
# c575b7ee 03-Apr-2018 Oleksandr Andrushchenko <[email protected]>

drm/xen-front: Add support for Xen PV display frontend

Add support for Xen para-virtualized frontend display driver.
Accompanying backend [1] is implemented as a user-space application
and its helpe

drm/xen-front: Add support for Xen PV display frontend

Add support for Xen para-virtualized frontend display driver.
Accompanying backend [1] is implemented as a user-space application
and its helper library [2], capable of running as a Weston client
or DRM master.
Configuration of both backend and frontend is done via
Xen guest domain configuration options [3].

Driver limitations:
1. Only primary plane without additional properties is supported.
2. Only one video mode supported which resolution is configured
via XenStore.
3. All CRTCs operate at fixed frequency of 60Hz.

1. Implement Xen bus state machine for the frontend driver according to
the state diagram and recovery flow from display para-virtualized
protocol: xen/interface/io/displif.h.

2. Read configuration values from Xen store according
to xen/interface/io/displif.h protocol:
- read connector(s) configuration
- read buffer allocation mode (backend/frontend)

3. Handle Xen event channels:
- create for all configured connectors and publish
corresponding ring references and event channels in Xen store,
so backend can connect
- implement event channels interrupt handlers
- create and destroy event channels with respect to Xen bus state

4. Implement shared buffer handling according to the
para-virtualized display device protocol at xen/interface/io/displif.h:
- handle page directories according to displif protocol:
- allocate and share page directories
- grant references to the required set of pages for the
page directory
- allocate xen balllooned pages via Xen balloon driver
with alloc_xenballooned_pages/free_xenballooned_pages
- grant references to the required set of pages for the
shared buffer itself
- implement pages map/unmap for the buffers allocated by the
backend (gnttab_map_refs/gnttab_unmap_refs)

5. Implement kernel modesetiing/connector handling using
DRM simple KMS helper pipeline:

- implement KMS part of the driver with the help of DRM
simple pipepline helper which is possible due to the fact
that the para-virtualized driver only supports a single
(primary) plane:
- initialize connectors according to XenStore configuration
- handle frame done events from the backend
- create and destroy frame buffers and propagate those
to the backend
- propagate set/reset mode configuration to the backend on display
enable/disable callbacks
- send page flip request to the backend and implement logic for
reporting backend IO errors on prepare fb callback

- implement virtual connector handling:
- support only pixel formats suitable for single plane modes
- make sure the connector is always connected
- support a single video mode as per para-virtualized driver
configuration

6. Implement GEM handling depending on driver mode of operation:
depending on the requirements for the para-virtualized environment,
namely requirements dictated by the accompanying DRM/(v)GPU drivers
running in both host and guest environments, number of operating
modes of para-virtualized display driver are supported:
- display buffers can be allocated by either
frontend driver or backend
- display buffers can be allocated to be contiguous
in memory or not

Note! Frontend driver itself has no dependency on contiguous memory for
its operation.

6.1. Buffers allocated by the frontend driver.

The below modes of operation are configured at compile-time via
frontend driver's kernel configuration.

6.1.1. Front driver configured to use GEM CMA helpers
This use-case is useful when used with accompanying DRM/vGPU driver
in guest domain which was designed to only work with contiguous
buffers, e.g. DRM driver based on GEM CMA helpers: such drivers can
only import contiguous PRIME buffers, thus requiring frontend driver
to provide such. In order to implement this mode of operation
para-virtualized frontend driver can be configured to use
GEM CMA helpers.

6.1.2. Front driver doesn't use GEM CMA
If accompanying drivers can cope with non-contiguous memory then, to
lower pressure on CMA subsystem of the kernel, driver can allocate
buffers from system memory.

Note! If used with accompanying DRM/(v)GPU drivers this mode of operation
may require IOMMU support on the platform, so accompanying DRM/vGPU
hardware can still reach display buffer memory while importing PRIME
buffers from the frontend driver.

6.2. Buffers allocated by the backend

This mode of operation is run-time configured via guest domain
configuration through XenStore entries.

For systems which do not provide IOMMU support, but having specific
requirements for display buffers it is possible to allocate such buffers
at backend side and share those with the frontend.
For example, if host domain is 1:1 mapped and has DRM/GPU hardware
expecting physically contiguous memory, this allows implementing
zero-copying use-cases.

Note, while using this scenario the following should be considered:
a) If guest domain dies then pages/grants received from the backend
cannot be claimed back
b) Misbehaving guest may send too many requests to the
backend exhausting its grant references and memory
(consider this from security POV).

Note! Configuration options 1.1 (contiguous display buffers) and 2
(backend allocated buffers) are not supported at the same time.

7. Handle communication with the backend:
- send requests and wait for the responses according
to the displif protocol
- serialize access to the communication channel
- time-out used for backend communication is set to 3000 ms
- manage display buffers shared with the backend

[1] https://github.com/xen-troops/displ_be
[2] https://github.com/xen-troops/libxenbe
[3] https://xenbits.xen.org/gitweb/?p=xen.git;a=blob;f=docs/man/xl.cfg.pod.5.in;h=a699367779e2ae1212ff8f638eff0206ec1a1cc9;hb=refs/heads/master#l1257

Signed-off-by: Oleksandr Andrushchenko <[email protected]>
Reviewed-by: Boris Ostrovsky <[email protected]>
Reviewed-by: Daniel Vetter <[email protected]>
Link: https://patchwork.freedesktop.org/patch/msgid/[email protected]

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Revision tags: v4.16, v4.16-rc7, v4.16-rc6
# 6d544fd6 16-Mar-2018 Daniel Vetter <[email protected]>

drm/doc: Put all driver docs into a separate chapter

We have quite a few driver docs now, which is great, but having them
all in the top-level gpu documentation chapter makes it harder to spot
the c

drm/doc: Put all driver docs into a separate chapter

We have quite a few driver docs now, which is great, but having them
all in the top-level gpu documentation chapter makes it harder to spot
the core/shared bits.

Stuff them into a separate chapter and ecourage people to add even
more!

Reviewed-by: Alex Deucher <[email protected]>
Signed-off-by: Daniel Vetter <[email protected]>
Link: https://patchwork.freedesktop.org/patch/msgid/[email protected]

show more ...