commit 659ab7a49cbebe0deffcbe1f9560e82006b21817 upstream.
USB devices cannot perform DMA and hence have no dma_mask set in their
device structure. Therefore importing dmabuf into a USB-based driver
fails, which breaks joining and mirroring of display in X11.
For USB devices, pick the associated USB controller as attachment device.
This allows the DRM import helpers to perform the DMA setup. If the DMA
controller does not support DMA transfers, we're out of luck and cannot
import. Our current USB-based DRM drivers don't use DMA, so the actual
DMA device is not important.
Tested by joining/mirroring displays of udl and radeon under Gnome/X11.
v8:
* release dmadev if device initialization fails (Noralf)
* fix commit description (Noralf)
v7:
* fix use-before-init bug in gm12u320 (Dan)
v6:
* implement workaround in DRM drivers and hold reference to
DMA device while USB device is in use
* remove dev_is_usb() (Greg)
* collapse USB helper into usb_intf_get_dma_device() (Alan)
* integrate Daniel's TODO statement (Daniel)
* fix typos (Greg)
v5:
* provide a helper for USB interfaces (Alan)
* add FIXME item to documentation and TODO list (Daniel)
v4:
* implement workaround with USB helper functions (Greg)
* use struct usb_device->bus->sysdev as DMA device (Takashi)
v3:
* drop gem_create_object
* use DMA mask of USB controller, if any (Daniel, Christian, Noralf)
v2:
* move fix to importer side (Christian, Daniel)
* update SHMEM and CMA helpers for new PRIME callbacks
Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Fixes: 6eb0233ec2 ("usb: don't inherity DMA properties for USB devices")
Tested-by: Pavel Machek <pavel@ucw.cz>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Acked-by: Christian König <christian.koenig@amd.com>
Acked-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Acked-by: Noralf Trønnes <noralf@tronnes.org>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: <stable@vger.kernel.org> # v5.10+
Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Link: https://patchwork.freedesktop.org/patch/msgid/20210303133229.3288-1-tzimmermann@suse.de
Signed-off-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 39aead8373b3c20bb5965c024dfb51a94e526151 upstream.
So ever since syzbot discovered fbcon, we have solid proof that it's
full of bugs. And often the solution is to just delete code and remove
features, e.g. 50145474f6 ("fbcon: remove soft scrollback code").
Now the problem is that most modern-ish drivers really only treat
fbcon as an dumb kernel console until userspace takes over, and Oops
printer for some emergencies. Looking at drm drivers and the basic
vesa/efi fbdev drivers shows that only 3 drivers support any kind of
acceleration:
- nouveau, seems to be enabled by default
- omapdrm, when a DMM remapper exists using remapper rewriting for
y/xpanning
- gma500, but that is getting deleted now for the GTT remapper trick,
and the accelerated copyarea never set the FBINFO_HWACCEL_COPYAREA
flag, so unused (and could be deleted already I think).
No other driver supportes accelerated fbcon. And fbcon is the only
user of this accel code (it's not exposed as uapi through ioctls),
which means we could garbage collect fairly enormous amounts of code
if we kill this.
Plus because syzbot only runs on virtual hardware, and none of the
drivers for that have acceleration, we'd remove a huge gap in testing.
And there's no other even remotely comprehensive testing aside from
syzbot.
This patch here just disables the acceleration code by always
redrawing when scrolling. The plan is that once this has been merged
for well over a year in released kernels, we can start to go around
and delete a lot of code.
v2:
- Drop a few more unused local variables, somehow I missed the
compiler warnings (Sam)
- Fix typo in comment (Jiri)
- add a todo entry for the cleanup (Thomas)
v3: Remove more unused variables (0day)
Reviewed-by: Tomi Valkeinen <tomi.valkeinen@ti.com>
Reviewed-by: Thomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Acked-by: Sam Ravnborg <sam@ravnborg.org>
Cc: Jiri Slaby <jirislaby@kernel.org>
Cc: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Ben Skeggs <bskeggs@redhat.com>
Cc: nouveau@lists.freedesktop.org
Cc: Tomi Valkeinen <tomi.valkeinen@ti.com>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: Jiri Slaby <jirislaby@kernel.org>
Cc: "Gustavo A. R. Silva" <gustavoars@kernel.org>
Cc: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Cc: Peilin Ye <yepeilin.cs@gmail.com>
Cc: George Kennedy <george.kennedy@oracle.com>
Cc: Nathan Chancellor <natechancellor@gmail.com>
Cc: Peter Rosin <peda@axentia.se>
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20201029132229.4068359-1-daniel.vetter@ffwll.ch
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
As reported by kernel-doc:
./drivers/gpu/drm/amd/amdgpu/amdgpu_xgmi.c:1: warning: no structured comments found
./drivers/gpu/drm/amd/amdgpu/amdgpu_ras.c:1: warning: no structured comments found
Those files only contain
/**
* DOC:
*/
markups, but they're included twice there: one to parse
such markup, and another one to parse internal functions.
In the case of amdgpu_xgmi.c, as it has just one such
markup, we can simply include the file once, and let it
parse the entire file without passing arguments to kernel-doc.
This should place everything altogether.
For amdgpu_ras.c, however, we need to remove the kernel-doc
with just internal. This should be re-introduced if this
file ever gets new non-DOC markups.
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Link: https://lore.kernel.org/r/bd070923591ae54f9587e7407b6291ac116952b2.1603791716.git.mchehab+huawei@kernel.org
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
Pull drm fixes from Dave Airlie:
"Some fixes queued up already for i915 and amdgpu, I've also included
the fix for the clang warning you've seen.
i915:
- set all unused color plane offsets to ~0xfff again (Ville)
- fix TGL DKL PHY DP vswing handling (Ville)
amdgpu:
- DCN clang warning fix
- eDP fix
- BACO fix
- kernel documentation fixes
- SMU7 mclk fix
- VCN1 hw bug workaround
amdkfd:
- kvfree vs kfree fix"
* tag 'drm-next-2020-10-19' of git://anongit.freedesktop.org/drm/drm:
drm/amd/display: Fix incorrect dsc force enable logic
drm/amdkfd: Use kvfree in destroy_crat_image
drm/amdgpu: vcn and jpeg ring synchronization
drm/amd/pm: increase mclk switch threshold to 200 us
docs: amdgpu: fix a warning when building the documentation
drm/amd/display: kernel-doc: document force_timing_sync
drm/amdgpu/swsmu: init the baco mutex in early_init
drm/amd/display: Fix module load hangs when connected to an eDP
drm/i915: Set all unused color plane offsets to ~0xfff again
drm/i915: Fix TGL DKL PHY DP vswing handling
Pull documentation updates from Mauro Carvalho Chehab:
"A series of patches addressing warnings produced by make htmldocs.
This includes:
- kernel-doc markup fixes
- ReST fixes
- Updates at the build system in order to support newer versions of
the docs build toolchain (Sphinx)
After this series, the number of html build warnings should reduce
significantly, and building with Sphinx 3.1 or later should now be
supported (although it is still recommended to use Sphinx 2.4.4).
As agreed with Jon, I should be sending you a late pull request by the
end of the merge window addressing remaining issues with docs build,
as there are a number of warning fixes that depends on pull requests
that should be happening along the merge window.
The end goal is to have a clean htmldocs build on Kernel 5.10.
PS. It should be noticed that Sphinx 3.0 is not currently supported,
as it lacks support for C domain namespaces. Such feature, needed in
order to document uAPI system calls with Sphinx 3.x, was added only on
Sphinx 3.1"
* tag 'docs/v5.10-1' of git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/linux-media: (75 commits)
PM / devfreq: remove a duplicated kernel-doc markup
mm/doc: fix a literal block markup
workqueue: fix a kernel-doc warning
docs: virt: user_mode_linux_howto_v2.rst: fix a literal block markup
Input: sparse-keymap: add a description for @sw
rcu/tree: docs: document bkvcache new members at struct kfree_rcu_cpu
nl80211: docs: add a description for s1g_cap parameter
usb: docs: document altmode register/unregister functions
kunit: test.h: fix a bad kernel-doc markup
drivers: core: fix kernel-doc markup for dev_err_probe()
docs: bio: fix a kerneldoc markup
kunit: test.h: solve kernel-doc warnings
block: bio: fix a warning at the kernel-doc markups
docs: powerpc: syscall64-abi.rst: fix a malformed table
drivers: net: hamradio: fix document location
net: appletalk: Kconfig: Fix docs location
dt-bindings: fix references to files converted to yaml
memblock: get rid of a :c:type leftover
math64.h: kernel-docs: Convert some markups into normal comments
media: uAPI: buffer.rst: remove a left-over documentation
...
As reported by Sphinx:
./Documentation/gpu/i915:646: ./drivers/gpu/drm/i915/i915_perf.c:1147: WARNING: Duplicate C declaration, also defined in 'gpu/i915'.
Declaration is 'i915_oa_wait_unlocked'.
./Documentation/gpu/i915:646: ./drivers/gpu/drm/i915/i915_perf.c:1169: WARNING: Duplicate C declaration, also defined in 'gpu/i915'.
Declaration is 'i915_oa_poll_wait'.
./Documentation/gpu/i915:646: ./drivers/gpu/drm/i915/i915_perf.c:1189: WARNING: Duplicate C declaration, also defined in 'gpu/i915'.
Declaration is 'i915_oa_read'.
./Documentation/gpu/i915:646: ./drivers/gpu/drm/i915/i915_perf.c:2669: WARNING: Duplicate C declaration, also defined in 'gpu/i915'.
Declaration is 'i915_oa_stream_enable'.
./Documentation/gpu/i915:646: ./drivers/gpu/drm/i915/i915_perf.c:2734: WARNING: Duplicate C declaration, also defined in 'gpu/i915'.
Declaration is 'i915_oa_stream_disable'.
./Documentation/gpu/i915:646: ./drivers/gpu/drm/i915/i915_perf.c:2820: WARNING: Duplicate C declaration, also defined in 'gpu/i915'.
Declaration is 'i915_oa_stream_init'.
./Documentation/gpu/i915:646: ./drivers/gpu/drm/i915/i915_perf.c:3010: WARNING: Duplicate C declaration, also defined in 'gpu/i915'.
Declaration is 'i915_perf_read'.
./Documentation/gpu/i915:646: ./drivers/gpu/drm/i915/i915_perf.c:3098: WARNING: Duplicate C declaration, also defined in 'gpu/i915'.
Declaration is 'i915_perf_poll_locked'.
./Documentation/gpu/i915:646: ./drivers/gpu/drm/i915/i915_perf.c:3129: WARNING: Duplicate C declaration, also defined in 'gpu/i915'.
Declaration is 'i915_perf_poll'.
./Documentation/gpu/i915:646: ./drivers/gpu/drm/i915/i915_perf.c:3152: WARNING: Duplicate C declaration, also defined in 'gpu/i915'.
Declaration is 'i915_perf_enable_locked'.
./Documentation/gpu/i915:646: ./drivers/gpu/drm/i915/i915_perf.c:3181: WARNING: Duplicate C declaration, also defined in 'gpu/i915'.
Declaration is 'i915_perf_disable_locked'.
./Documentation/gpu/i915:646: ./drivers/gpu/drm/i915/i915_perf.c:3273: WARNING: Duplicate C declaration, also defined in 'gpu/i915'.
Declaration is 'i915_perf_ioctl'.
./Documentation/gpu/i915:646: ./drivers/gpu/drm/i915/i915_perf.c:3296: WARNING: Duplicate C declaration, also defined in 'gpu/i915'.
Declaration is 'i915_perf_destroy_locked'.
./Documentation/gpu/i915:646: ./drivers/gpu/drm/i915/i915_perf.c:3321: WARNING: Duplicate C declaration, also defined in 'gpu/i915'.
Declaration is 'i915_perf_release'.
./Documentation/gpu/i915:646: ./drivers/gpu/drm/i915/i915_perf.c:3379: WARNING: Duplicate C declaration, also defined in 'gpu/i915'.
Declaration is 'i915_perf_open_ioctl_locked'.
./Documentation/gpu/i915:646: ./drivers/gpu/drm/i915/i915_perf.c:3534: WARNING: Duplicate C declaration, also defined in 'gpu/i915'.
Declaration is 'read_properties_unlocked'.
./Documentation/gpu/i915:646: ./drivers/gpu/drm/i915/i915_perf.c:3717: WARNING: Duplicate C declaration, also defined in 'gpu/i915'.
Declaration is 'i915_perf_open_ioctl'.
./Documentation/gpu/i915:646: ./drivers/gpu/drm/i915/i915_perf.c:3760: WARNING: Duplicate C declaration, also defined in 'gpu/i915'.
Declaration is 'i915_perf_register'.
./Documentation/gpu/i915:646: ./drivers/gpu/drm/i915/i915_perf.c:3789: WARNING: Duplicate C declaration, also defined in 'gpu/i915'.
Declaration is 'i915_perf_unregister'.
./Documentation/gpu/i915:646: ./drivers/gpu/drm/i915/i915_perf.c:4009: WARNING: Duplicate C declaration, also defined in 'gpu/i915'.
Declaration is 'i915_perf_add_config_ioctl'.
./Documentation/gpu/i915:646: ./drivers/gpu/drm/i915/i915_perf.c:4162: WARNING: Duplicate C declaration, also defined in 'gpu/i915'.
Declaration is 'i915_perf_remove_config_ioctl'.
./Documentation/gpu/i915:646: ./drivers/gpu/drm/i915/i915_perf.c:4260: WARNING: Duplicate C declaration, also defined in 'gpu/i915'.
Declaration is 'i915_perf_init'.
./Documentation/gpu/i915:646: ./drivers/gpu/drm/i915/i915_perf.c:4423: WARNING: Duplicate C declaration, also defined in 'gpu/i915'.
Declaration is 'i915_perf_fini'.
With Sphinx 3, C declarations can't be duplicated anymore,
so let's exclude those from the other internals found on
i915_perf.c file.
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
As reported by Sphinx:
Documentation/gpu/amdgpu.rst:200: WARNING: Inline emphasis start-string without end-string.
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Added IP block section to amdgpu.rst.
Added more documentation to amd_ip_funcs.
Created documentation for amd_ip_block_type.
v2: Provides a more detailed DOC section on IP blocks
v3: Clarifies the IP block list. Adds info on IP block enumeration.
Signed-off-by: Ryan Taylor <ryan.taylor@amd.com>
Reviewed-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Fix Documentation errors for amdgpu.rst due to file rename (moved
to another subdirectory).
Error: Cannot open file ../drivers/gpu/drm/amd/amdgpu/amdgpu_pm.c
WARNING: kernel-doc '../scripts/kernel-doc -rst -enable-lineno -function hwmon ../drivers/gpu/drm/amd/amdgpu/amdgpu_pm.c' failed with return code 1
Fixes: e098bc9612 ("drm/amd/pm: optimize the power related source code layout")
Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Cc: Evan Quan <evan.quan@amd.com>
Cc: Alex Deucher <alexander.deucher@amd.com>
Reviewed-by: Evan Quan <evan.quan@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Pull drm updates from Dave Airlie:
"New xilinx displayport driver, AMD support for two new GPUs (more
header files), i915 initial support for RocketLake and some work on
their DG1 (discrete chip).
The core also grew some lockdep annotations to try and constrain what
drivers do with dma-fences, and added some documentation on why the
idea of indefinite fences doesn't work.
The long list is below.
I do have some fixes trees outstanding, but I'll follow up with those
later.
core:
- add user def flag to cmd line modes
- dma_fence_wait added might_sleep
- dma-fence lockdep annotations
- indefinite fences are bad documentation
- gem CMA functions used in more drivers
- struct mutex removal
- more drm_ debug macro usage
- set/drop master api fixes
- fix for drm/mm hole size comparison
- drm/mm remove invalid entry optimization
- optimise drm/mm hole handling
- VRR debugfs added
- uncompressed AFBC modifier support
- multiple display id blocks in EDID
- multiple driver sg handling fixes
- __drm_atomic_helper_crtc_reset in all drivers
- managed vram helpers
ttm:
- ttm_mem_reg handling cleanup
- remove bo offset field
- drop CMA memtype flag
- drop mappable flag
xilinx:
- New Xilinx ZynqMP DisplayPort Subsystem driver
nouveau:
- add CRC support
- start using NVIDIA published class header files
- convert all push buffer emission to new macros
- Proper push buffer space management for EVO/NVD channels.
- firmware loading fixes
- 2MiB system memory pages support on Pascal and newer
vkms:
- larger cursor support
i915:
- Rocketlake platform enablement
- Early DG1 enablement
- Numerous GEM refactorings
- DP MST fixes
- FBC, PSR, Cursor, Color, Gamma fixes
- TGL, RKL, EHL workaround updates
- TGL 8K display support fixes
- SDVO/HDMI/DVI fixes
amdgpu:
- Initial support for Sienna Cichlid GPU
- Initial support for Navy Flounder GPU
- SI UVD/VCE support
- expose rotation property
- Add support for unique id on Arcturus
- Enable runtime PM on vega10 boards that support BACO
- Skip BAR resizing if the bios already did id
- Major swSMU code cleanup
- Fixes for DCN bandwidth calculations
amdkfd:
- Track SDMA usage per process
- SMI events interface
radeon:
- Default to on chip GART for AGP boards on all arches
- Runtime PM reference count fixes
msm:
- headers regenerated causing churn
- a650/a640 display and GPU enablement
- dpu dither support for 6bpc panels
- dpu cursor fix
- dsi/mdp5 enablement for sdm630/sdm636/sdm66
tegra:
- video capture prep support
- reflection support
mediatek:
- convert mtk_dsi to bridge API
meson:
- FBC support
sun4i:
- iommu support
rockchip:
- register locking fix
- per-pixel alpha support PX30 VOP
mgag200:
- ported to simple and shmem helpers
- device init cleanups
- use managed pci functions
- dropped hw cursor support
ast:
- use managed pci functions
- use managed VRAM helpers
- rework cursor support
malidp:
- dev_groups support
hibmc:
- refactor hibmc_drv_vdac:
vc4:
- create TXP CRTC
imx:
- error path fixes and cleanups
etnaviv:
- clock handling and error handling cleanups
- use pin_user_pages"
* tag 'drm-next-2020-08-06' of git://anongit.freedesktop.org/drm/drm: (1747 commits)
drm/msm: use kthread_create_worker instead of kthread_run
drm/msm/mdp5: Add MDP5 configuration for SDM636/660
drm/msm/dsi: Add DSI configuration for SDM660
drm/msm/mdp5: Add MDP5 configuration for SDM630
drm/msm/dsi: Add phy configuration for SDM630/636/660
drm/msm/a6xx: add A640/A650 hwcg
drm/msm/a6xx: hwcg tables in gpulist
drm/msm/dpu: add SM8250 to hw catalog
drm/msm/dpu: add SM8150 to hw catalog
drm/msm/dpu: intf timing path for displayport
drm/msm/dpu: set missing flush bits for INTF_2 and INTF_3
drm/msm/dpu: don't use INTF_INPUT_CTRL feature on sdm845
drm/msm/dpu: move some sspp caps to dpu_caps
drm/msm/dpu: update UBWC config for sm8150 and sm8250
drm/msm/dpu: use right setup_blend_config for sm8150 and sm8250
drm/msm/a6xx: set ubwc config for A640 and A650
drm/msm/adreno: un-open-code some packets
drm/msm: sync generated headers
drm/msm/a6xx: add build_bw_table for A640/A650
drm/msm/a6xx: fix crashstate capture for A650
...
Pull documentation updates from Jonathan Corbet:
"It's been a busy cycle for documentation - hopefully the busiest for a
while to come. Changes include:
- Some new Chinese translations
- Progress on the battle against double words words and non-HTTPS
URLs
- Some block-mq documentation
- More RST conversions from Mauro. At this point, that task is
essentially complete, so we shouldn't see this kind of churn again
for a while. Unless we decide to switch to asciidoc or
something...:)
- Lots of typo fixes, warning fixes, and more"
* tag 'docs-5.9' of git://git.lwn.net/linux: (195 commits)
scripts/kernel-doc: optionally treat warnings as errors
docs: ia64: correct typo
mailmap: add entry for <alobakin@marvell.com>
doc/zh_CN: add cpu-load Chinese version
Documentation/admin-guide: tainted-kernels: fix spelling mistake
MAINTAINERS: adjust kprobes.rst entry to new location
devices.txt: document rfkill allocation
PCI: correct flag name
docs: filesystems: vfs: correct flag name
docs: filesystems: vfs: correct sync_mode flag names
docs: path-lookup: markup fixes for emphasis
docs: path-lookup: more markup fixes
docs: path-lookup: fix HTML entity mojibake
CREDITS: Replace HTTP links with HTTPS ones
docs: process: Add an example for creating a fixes tag
doc/zh_CN: add Chinese translation prefer section
doc/zh_CN: add clearing-warn-once Chinese version
doc/zh_CN: add admin-guide index
doc:it_IT: process: coding-style.rst: Correct __maybe_unused compiler label
futex: MAINTAINERS: Re-add selftests directory
...
Rationale:
Reduces attack surface on kernel devs opening the links for MITM
as HTTPS traffic is much harder to manipulate.
Deterministic algorithm:
For each file:
If not .svg:
For each line:
If doesn't contain `\bxmlns\b`:
For each link, `\bhttp://[^# \t\r\n]*(?:\w|/)`:
If neither `\bgnu\.org/license`, nor `\bmozilla\.org/MPL\b`:
If both the HTTP and HTTPS versions
return 200 OK and serve the same content:
Replace HTTP with HTTPS.
Signed-off-by: Alexander A. Klimov <grandmaster@al2klimov.de>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/20200719171428.60470-1-grandmaster@al2klimov.de
Add some kind of vblank workers. The interface is similar to regular
delayed works, and is mostly based off kthread_work. It allows for
scheduling delayed works that execute once a particular vblank sequence
has passed. It also allows for accurate flushing of scheduled vblank
works - in that flushing waits for both the vblank sequence and job
execution to complete, or for the work to get cancelled - whichever
comes first.
Whatever hardware programming we do in the work must be fast (must at
least complete during the vblank or scanout period, sometimes during the
first few scanlines of the vblank). As such we use a high-priority
per-CRTC thread to accomplish this.
Changes since v7:
* Stuff drm_vblank_internal.h and drm_vblank_work_internal.h contents
into drm_internal.h
* Get rid of unnecessary spinlock in drm_crtc_vblank_on()
* Remove !vblank->worker check
* Grab vbl_lock in drm_vblank_work_schedule()
* Mention self-rearming work items in drm_vblank_work_schedule() kdocs
* Return 1 from drm_vblank_work_schedule() if the work was scheduled
successfully, 0 or error code otherwise
* Use drm_dbg_core() instead of DRM_DEV_ERROR() in
drm_vblank_work_schedule()
* Remove vblank->worker checks in drm_vblank_destroy_worker() and
drm_vblank_flush_worker()
Changes since v6:
* Get rid of ->pending and seqcounts, and implement flushing through
simpler means - danvet
* Get rid of work_lock, just use drm_device->event_lock
* Move drm_vblank_work item cleanup into drm_crtc_vblank_off() so that
we ensure that all vblank work has finished before disabling vblanks
* Add checks into drm_crtc_vblank_reset() so we yell if it gets called
while there's vblank workers active
* Grab event_lock in both drm_crtc_vblank_on()/drm_crtc_vblank_off(),
the main reason for this is so that other threads calling
drm_vblank_work_schedule() are blocked from attempting to schedule
while we're in the middle of enabling/disabling vblanks.
* Move drm_handle_vblank_works() call below drm_handle_vblank_events()
* Simplify drm_vblank_work_cancel_sync()
* Fix drm_vblank_work_cancel_sync() documentation
* Move wake_up_all() calls out of spinlock where we can. The only one I
left was the call to wake_up_all() in drm_vblank_handle_works() as
this seemed like it made more sense just living in that function
(which is all technically under lock)
* Move drm_vblank_work related functions into their own source files
* Add drm_vblank_internal.h so we can export some functions we don't
want drivers using, but that we do need to use in drm_vblank_work.c
* Add a bunch of documentation
Changes since v4:
* Get rid of kthread interfaces we tried adding and move all of the
locking into drm_vblank.c. For implementing drm_vblank_work_flush(),
we now use a wait_queue and sequence counters in order to
differentiate between multiple work item executions.
* Get rid of drm_vblank_work_cancel() - this would have been pretty
difficult to actually reimplement and it occurred to me that neither
nouveau or i915 are even planning to use this function. Since there's
also no async cancel function for most of the work interfaces in the
kernel, it seems a bit unnecessary anyway.
* Get rid of to_drm_vblank_work() since we now are also able to just
pass the struct drm_vblank_work to work item callbacks anyway
Changes since v3:
* Use our own spinlocks, don't integrate so tightly with kthread_works
Changes since v2:
* Use kthread_workers instead of reinventing the wheel.
Cc: Tejun Heo <tj@kernel.org>
Cc: dri-devel@lists.freedesktop.org
Cc: nouveau@lists.freedesktop.org
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Co-developed-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: Lyude Paul <lyude@redhat.com>
Acked-by: Dave Airlie <airlied@gmail.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200627194657.156514-4-lyude@redhat.com
drm-misc-next for v5.9:
UAPI Changes:
- Add DRM_MODE_TYPE_USERDEF for video modes specified in cmdline.
Cross-subsystem Changes:
- Assorted devicetree binding updates.
- Add might_sleep() to dma_fence_wait().
- Fix fbdev's get_user_pages_fast() handling, and use pin_user_pages.
- Small cleanup with IS_BUILTIN in video/fbdev drivers.
- Fix video/hdmi coding style for infoframe size.
Core Changes:
- Silence vblank output during init.
- Fix DP-MST corruption during send msg timeout.
- Clear leak in drm_gem_objecs_lookup().
- Make newlines work with force connector attribute.
- Fix module refcounting error in drm_encoder_slave, and use new i2c api.
- Header fix for drm_managed.c
- More struct_mutex removal for !legacy drivers:
- Remove gem_free_object()
- Removal of drm_gem_object_put_unlocked().
- Show current->comm alongside pid in debug printfs.
- Add drm_client_modeset_check() + drm_client_framebuffer_flush().
- Replace drm_fb_swab16 with drm_fb_swap that also supports 32-bits.
- Remove mode->vrefresh, and compactify drm_display_mode.
- Use drm_* macros for logging and warnings.
- Add WARN when drm_gem_get_pages is used on a private obj.
- Handle importing and imported dmabuf better in shmem helpers.
- Small fix for drm/mm hole size comparison, and remove invalid entry optimization.
- Add a drm/mm selftest.
- Set DSI connector type for DSI panels.
- Assorted small fixes and documentation updates.
- Fix DDI I2C device registration for MST ports, and flushing on destroy.
- Fix master_set return type, used by vmwgfx.
- Make the drm_set/drop_master ioctl symmetrical.
Driver Changes:
Allow iommu in the sun4i driver and use it for sun8i.
- Simplify backlight lookup for omap, amba-clcd and tilcdc.
- Hold reg_lock for rockchip.
- Add support for bridge gpio and lane reordering + polarity to ti-sn65dsi86, and fix clock choice.
- Small assorted fixes to tilcdc, vc4, i915, omap, fbdev/sm712fb, fbdev/pxafb, console/newport_con, msm, virtio, udl, malidp, hdlcd, bridge/ti-sn65dsi86, panfrost.
- Remove hw cursor support for mgag200, and use simple kms helper + shmem helpers.
- Add support for KOE Allow iommu in the sun4i driver and use it for sun8i.
- Simplify backlight lookup for omap, amba-clcd and tilcdc.
- Hold reg_lock for rockchip.
- Add support for bridge gpio and lane reordering + polarity to ti-sn65dsi86, and fix clock choice.
- Small assorted fixes to tilcdc, vc4 (multiple), i915.
- Remove hw cursor support for mgag200, and use simple kms helper + shmem helpers.
- Add support for KOE TX26D202VM0BWA panel.
- Use GEM CMA functions in arc, arm, atmel-hlcdc, fsi-dcu, hisilicon, imx, ingenic, komeda, malidp, mcde, meson, msxfb, rcar-du, shmobile, stm, sti, tilcdc, tve200, zte.
- Remove gem_print_info.
- Improve gem_create_object_helper so udl can use shmem helpers.
- Convert vc4 dt bindings to schemas, and add clock properties.
- Device initialization cleanups for mgag200.
- Add a workaround to fix DP-MST short pulses handling on broken hardware in i915.
- Allow build test compiling arm drivers.
- Use managed pci functions in mgag200 and ast.
- Use dev_groups in malidp.
- Add per pixel alpha support for PX30 VOP in rockchip.
- Silence deferred probe logs in panfrost.
Signed-off-by: Dave Airlie <airlied@redhat.com>
From: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/001cd9a6-405d-4e29-43d8-354f53ae4e8b@linux.intel.com
Add rename the gpu busy percentage for consistency and
add the mem busy percentage documentation.
Reviewed-by: Evan Quan <evan.quan@amd.com>
Reviewed-by: Nirmoy Das <nirmoy.das@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
- Move the shmem helper section to the drm-mm.rst file, next to the
vram helpers. Makes a lot more sense there with the now wider scope.
Also, that's where the all the other backing storage stuff resides.
It's just the framebuffer helpers that should be in the kms helper
section.
- Try to clarify which functiosn are for implementing
drm_gem_object_funcs, and which for drivers to call directly. At
least one driver screwed that up a bit.
Cc: Gerd Hoffmann <kraxel@redhat.com>
Cc: Rob Herring <robh@kernel.org>
Cc: Noralf Trønnes <noralf@tronnes.org>
Reviewed-by: Thomas Zimmermann <tzimmermann@suse.de>
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200511093554.211493-4-daniel.vetter@ffwll.ch
UAPI Changes:
- drm/i915: Show per-engine default property values in sysfs
By providing the default values configured into the kernel via sysfs, it
is much more convenient for userspace to restore those sane defaults, or
at least know what are considered good baseline. This is useful, for
example, to cleanup after any failed userspace prior to commencing new
jobs.
Cross-subsystem Changes:
- video/hdmi: Add Unpack only function for DRM infoframe
- Includes pull request gvt-next-2020-05-12
Driver Changes:
- Restore Cherryview back to full-ppgtt (Chris, Mika)
- Document locking guidelines for i915 (Chris, Daniel, Joonas)
- Fix GitLab #1746: Handle idling during i915_gem_evict_something busy loops (Chris)
- Display WA #1105: Require linear fb stride to be multiple of 512 bytes on
gen9/glk (Ville)
- Add Wa_14010685332 for ICP/ICL (Matt R)
- Restrict w/a 1607087056 for EHL/JSL (Swathi)
- Fix interrupt handling for DP AUX transactions on Tigerlake (Imre)
- Revert "drm/i915/tgl: Include ro parts of l3 to invalidate" (Mika)
- Fix HDC pipeline flush hardware bit on Gen12 (Mika)
- Flush L3 when flushing render on Gen12 (Mika)
- Invalidate aux table entries forcibly between BB on Gen12 (Mika)
- Add aux table invalidate for all engines on Gen12 (Mika)
- Force pte cacheline to main memory Gen8+ (Mika)
- Add and enable TGL+ SAGV support (Stanislav)
- Implement vm_ops->access on i915 mmaps for GDB (Chris, Kristian)
- Replace zero-length array with flexible-array (Gustavo)
- Improve batch buffer pool effectiveness to mitigate soft-rc6 hit (Chris)
- Remove wait priority boosting (Chris)
- Keep driver module referenced when PMU is active (Chris)
- Sanitize RPS interrupts upon resume (Chris)
- Extend pcode read timeout to 20 ms (Chris)
- Wait for ACT sent before enabling MST pipe (Ville)
- Extend support to async relocations to SNB (Chris)
- Remove CNL pre-prod workarounds (Ville)
- Don't enable WaIncreaseLatencyIPCEnabled when IPC is disabled (Sultan)
- Record the active CCID from before reset (Chris)
- Mark concurrent submissions with a weak-dependency (Chris)
- Peel dma-fence-chains for await to allow engine-to-engine sync (Lionel)
- Prevent using semaphores to chain up to external fences (Chris)
- Fix GLK watermark calculations (Ville)
- Emit await(batch) before MI_BB_START (Chris)
- Reset execlists registers before HWSP (Chris)
- Drop no-semaphore boosting in favor of fast timeslicing (Chris)
- Fix enabled infoframe states of lspcon (Gwan-gyeong)
- Program DP SDPs on pipe updates (Gwan-gyeong)
- Stop sending DP SDPs on ddi disable (Gwan-gyeong)
- Store CS timestamp frequency in Hz (Ville)
- Remove unused HAS_FWTABLE macro (Pascal)
- Use batchbuffer chaining for relocations to save ring space (Chris)
- Try different engines for relocs if MI ops not supported (Chris, Tvrtko)
- Lazily acquire the device wakeref for freeing objects (Chris)
- Streamline display code arithmetics around rounding etc. (Ville)
- Use bw state for per crtc SAGV evaluation (Stanislav)
- Track active_pipes in bw_state (Stanislav)
- Nuke mode.vrefresh usage (Ville)
- Warn if the FBC is still writing to stolen on removal (Chris)
- Added new PCode commands prepping for QGV rescricting (Stansilav)
- Stop holding onto the pinned_default_state (Chris)
- Propagate error from completed fences (Chris)
- Ignore submit-fences on the same timeline (Chris)
- Pull waiting on an external dma-fence into its routine (Chris)
- Replace the hardcoded I915_FENCE_TIMEOUT with Kconfig (Chris)
- Mark up the racy read of execlists->context_tag (Chris)
- Tidy up the return handling for completed dma-fences (Chris)
- Introduce skl_plane_wm_level accessor (Stanislav)
- Extract SKL SAGV checking (Stanislav)
- Make active_pipes check skl specific (Stanislav)
- Suspend tasklets before resume sanitization (Chris)
- Remove redundant exec_fence (Chris)
- Mark the addition of the initial-breadcrumb in the request (Chris)
- Transfer old virtual breadcrumbs to irq_worker (Chris)
- Read the DP SDPs from the video DIP (Gwan-gyeong)
- Program DP SDPs with computed configs (Gwan-gyeong)
- Add state readout for DP VSC and DP HDR Metadata Infoframe SDP
(Gwan-gyeong)
- Add compute routine for DP PSR VSC SDP (Gwan-gyeong)
- Use new DP VSC SDP compute routine on PSR (Gwan-gyeong)
- Restrict qgv points which don't have enough bandwidth. (Stanislav)
- Nuke pointless div by 64bit (Ville)
- Static checker code fixes (Nathan, Mika, Chris)
- Add logging function for DP VSC SDP (Gwan-gyeong)
- Include HDMI DRM infoframe, DP HDR metadata and DP VSC SDP in the
crtc state dump (Gwan-gyeong)
- Make timeslicing explicit engine property (Chris, Tvrtko)
- Selftest and debugging improvements (Chris)
- Align variable names with BSpec (Ville)
- Tidy up gen8+ breadcrumb emission code (Chris)
- Turn intel_digital_port_connected() in a vfunc (Ville)
- Use stashed away hpd isr bits in intel_digital_port_connected() (Ville)
- Extract i915_cs_timestamp_{ns_to_ticks,tick_to_ns}() (Ville)
Signed-off-by: Dave Airlie <airlied@redhat.com>
From: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200515160703.GA19043@jlahtine-desk.ger.corp.intel.com
Spelling out _unlocked for each and every driver is a annoying.
Especially if we consider how many drivers, do not know (or need to)
about the horror stories involving struct_mutex.
Just drop the suffix. It makes the API cleaner.
Done via the following script:
__from=drm_gem_object_put_unlocked
__to=drm_gem_object_put
for __file in $(git grep --name-only $__from); do
sed -i "s/$__from/$__to/g" $__file;
done
Pay special attention to the compat #define
v2: keep sed and #define removal separate
Cc: David Airlie <airlied@linux.ie>
Cc: Daniel Vetter <daniel@ffwll.ch>
Signed-off-by: Emil Velikov <emil.velikov@collabora.com>
Acked-by: Sam Ravnborg <sam@ravnborg.org> (v1)
Reviewed-by: Steven Price <steven.price@arm.com>
Acked-by: Thomas Zimmermann <tzimmermann@suse.de>
Link: https://patchwork.freedesktop.org/patch/msgid/20200515095118.2743122-14-emil.l.velikov@gmail.com
drm-misc-next for 5.8:
UAPI Changes:
Cross-subsystem Changes:
* MAINTAINERS: restore alphabetical order; update cirrus driver
* Dcomuentation: document visionix, chronteli, ite vendor prefices; update
documentation for Chrontel CH7033, IT6505, IVO, BOE,
Panasonic, Chunghwa, AUO bindings; convert dw_mipi_dsi.txt
to YAML; remove todo item for drm_display_mode.hsync removal;
Core Changes:
* drm: add devm_drm_dev_alloc() for managed allocations of drm_device;
use DRM_MODESET_LOCK_ALL_*() in mode-object code; remove
drm_display_mode.hsync; small cleanups of unused variables,
compiler warnings and static functions
* drm/client: dual-lincensing: GPL-2.0 or MIT
* drm/mm: optimize tree searches in rb_hole_addr()
Driver Changes:
* drm/{many}: use devm_drm_dev_alloc(); don't use drm_device.dev_private
* drm/ast: don't double-assign to drm_crtc_funcs.set_config; drop
drm_connector_register()
* drm/bochs: drop drm_connector_register()
* drm/bridge: add support for Chrontel ch7033; fix stack usage with
old gccs; return error pointer in drm_panel_bridge_add()
* drm/cirrus: Move to tiny
* drm/dp_mst: don't use 2nd sideband tx slot; revert "Remove single tx
msg restriction"
* drm/lima: support runtime PM;
* drm/meson: limit modes wrt chipset
* drm/panel: add support for Visionox rm69299; fix clock on
boe-tv101wum-n16; fix panel type for AUO G101EVN10;
add support for Ivo M133NFW4 R0; add support for BOE
NV133FHM-N61; add support for AUO G121EAN01.4, G156XTN01.0,
G190EAN01
* drm/pl111: improve vexpress init; fix module auto-loading
* drm/stm: read number of endpoints from device tree
* drm/vboxvideo: use managed PCI functions; drop DRM_MTRR_WC
* drm/vkms: fix use-after-free in vkms_gem_create(); enable cursor
support by default
* fbdev: use boolean values in several drivers
* fbdev/controlfb: fix COMPILE_TEST
* fbdev/w100fb: fix double-free bug
Signed-off-by: Dave Airlie <airlied@redhat.com>
From: Thomas Zimmermann <tzimmermann@suse.de>
Link: https://patchwork.freedesktop.org/patch/msgid/20200507072503.GA10979@linux-uq9g
drm-misc-next for 5.8:
UAPI Changes:
- drm: error out with EBUSY when device has existing master
- drm: rework SET_MASTER and DROP_MASTER perm handling
Cross-subsystem Changes:
- mm: export two symbols from slub/slob
- fbdev: savage: fix -Wextra build warning
- video: omap2: Use scnprintf() for avoiding potential buffer overflow
Core Changes:
- Remove drm_pci.h
- drm_pci_{alloc/free)() are now legacy
- Introduce managed DRM resourcesA
- Allow drivers to subclass struct drm_framebuffer
- Introduce struct drm_afbc_framebuffer and helpers
- fbdev: remove return value from generic fbdev setup
- Introduce simple-encoder helper
- vram-helpers: set fence on plane
- dp_mst: ACT timeout improvements
- dp_mst: Remove drm_dp_mst_has_audio()
- TTM: ttm_trace_dma_{map/unmap}() cleanups
- dma-buf: add flag for PCIP2P support
- EDID: Various improvements
- Encoder: cleanup semantics of possible_clones and possible_crtcs
- VBLANK documentation updates
- Writeback documentation updates
Driver Changes:
- Convert several drivers to i2c_new_client_device()
- Drop explicit drm_mode_config_cleanup() calls from drivers
- Auto-release device structures with drmm_add_final_kfree()
- Init bfdev console after registering DRM device
- Make various .debugfs functions return 0 unconditionally; ignore errors
- video: Use scnprintf() to avoid buffer overflows
- Convert drivers to simple encoders
- drm/amdgpu: note that we can handle peer2peer DMA-buf
- drm/amdgpu: add support for exporting VRAM using DMA-buf v3
- drm/kirin: Revert change to register connectors
- drm/lima: Add optional devfreq and cooling device support
- drm/lima: Various improvements wrt. task handling
- drm/panel: nt39016: Support multiple modes and 50Hz
- drm/panel: Support Leadtek LTK050H3146W
- drm/rockchip: Add support for afbc
- drm/virtio: Various cleanups
- drm/hisilicon/hibmc: Enforce 128-byte stride alignment
- drm/qxl: Fix notify port address of cursor ring buffer
- drm/sun4i: Improvements to format handling
- drm/bridge: dw-hdmi: Various improvements
Signed-off-by: Dave Airlie <airlied@redhat.com>
From: Thomas Zimmermann <tzimmermann@suse.de>
Link: https://patchwork.freedesktop.org/patch/msgid/20200414090738.GA16827@linux-uq9g
Allow for reading of information like manufacturer, product number
and serial number from the FRU chip. Report the serial number as
the new sysfs file serial_number. Note that this only works on
server cards, as consumer cards do not feature the FRU chip, which
contains this information.
v2: Add documentation to amdgpu.rst, add helper functions,
rename functions for consistency, fix bad starting offset
v3: Remove testing definitions
Signed-off-by: Kent Russell <kent.russell@amd.com>
Reviewed-by: Andrey Grodzovsky <andrey.grodzovsky@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
All collected together to provide a consistent story in one patch,
instead of the somewhat bumpy refactor-evolution leading to this.
Also some thoughts on what the next steps could be:
- Create a macro called devm_drm_dev_alloc() which essentially wraps
the kzalloc(); devm_drm_dev_init(); drmm_add_final_kfree() combo.
Needs to be a macro since we'll have to do some typeof trickery and
casting to make this fully generic for all drivers that embed struct
drm_device into their own thing.
- A lot of the simple drivers now have essentially just
drm_dev_unplug(); drm_atomic_helper_shutdown(); as their
$bus_driver->remove hook. We could create a devm_mode_config_reset
which sets drm_atomic_helper_shutdown as it's cleanup action, and a
devm_drm_dev_register with drm_dev_unplug as it's cleanup action,
and simple drivers wouldn't have a need for a ->remove function at
all, and we could delete them.
- For more complicated drivers we need drmm_ versions of a _lot_ more
things. All the userspace visible objects (crtc, plane, encoder,
crtc), anything else hanging of those (maybe a drmm_get_edid, at
least for panels and other built-in stuff).
Also some more thoughts on why we're not reusing devm_ with maybe a
fake struct device embedded into the drm_device (we can't use the
kdev, since that's in each drm_minor).
- Code review gets extremely tricky, since every time you see a devm_
you need to carefully check whether the fake device (with the
drm_device lifetim) or the real device (with the lifetim of the
underlying physical device and driver binding) are used. That's not
going to help at all, and we have enormous amounts of drivers who
use devm_ where they really shouldn't. Having different types makes
sure the compiler type checks this for us and ensures correctness.
- The set of functions are very much non-overlapping. E.g.
devm_ioremap makes total sense, drmm_ioremap has the wrong lifetime,
since hw resources need to be cleaned out at driver unbind and wont
outlive that like a drm_device. Similar, but other way round for
drmm_connector_init (which is the only correct version, devm_ for
drm_connector is just buggy). Simply not having the wrong version
again prevents bugs.
Finally I guess this opens a huge todo for all the drivers. I'm
semi-tempted to do a tree-wide s/devm_kzalloc/drmm_kzalloc/ since most
likely that'll fix an enormous amount of bugs and most likely not
cause any issues at all (aside from maybe holding onto memory slightly
too long).
v2:
- Doc improvements from Laurent.
- Also add kerneldoc for the new drmm_add_action_or_reset.
v3:
- Remove kerneldoc for drmm_remove_action.
Reviewed-by: Sam Ravnborg <sam@ravnborg.org>
Cc: Sam Ravnborg <sam@ravnborg.org>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: linux-doc@vger.kernel.org
Cc: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: "Rafael J. Wysocki" <rafael@kernel.org>
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
fixup docs
Link: https://patchwork.freedesktop.org/patch/msgid/20200323144950.3018436-52-daniel.vetter@ffwll.ch
drm_mode_config_cleanup is idempotent, so no harm in calling this
twice. This allows us to gradually switch drivers over by removing
explicit drm_mode_config_cleanup calls.
With this step it's now also possible that (at least for simple
drivers) automatic resource cleanup can be done correctly without a
drm_driver->release hook. Therefore allow this now in
devm_drm_dev_init().
Also with drmm_ explicit drm_driver->release hooks are kinda not the
best option: Drivers can always just register their current release
hook with drmm_add_action, but even better they could split them up to
simplify the unwinding for the driver load failure case. So deprecate
that hook to discourage future users.
v2: Fixup the example in the kerneldoc too.
v3:
- For paranoia, double check that minor->dev == dev in the release
hook, because I botched the pointer math in the drmm library.
- Call drm_mode_config_cleanup when drmm_add_action fails, we'd be
missing some mutex_destroy and ida_cleanup otherwise (Laurent)
v4: Add a drmm_add_action_or_reset (like devm_ has) to encapsulate this
pattern (Noralf).
v5: Fix oversight in the new drmm_add_action_or_reset macro (Noralf)
v4: Review from Sam:
- drmm_mode_config_init wrapper (also suggested by Thomas)
- improve commit message, explain better why ->relase is deprecated
v5:
- Make drmm_ the main function, with the old one as compat wrapper
(Sam)
- Add FIXME comments to drm_mode_config_cleanup/init() that drivers
shouldn't use these anymore.
- Move drmm_add_action_or_reset helper to an earlier patch.
Reviewed-by: Sam Ravnborg <sam@ravnborg.org>
Cc: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Cc: "Noralf Trønnes" <noralf@tronnes.org>
Cc: Sam Ravnborg <sam@ravnborg.org>
Cc: Thomas Zimmermann <tzimmermann@suse.de>
Acked-by: Noralf Trønnes <noralf@tronnes.org>
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200323144950.3018436-27-daniel.vetter@ffwll.ch