Occasionally it's necessary for drivers to modify the SADs of an ELD,
but it's not so cool to have drivers poke at the ELD buffer directly.
Using the helpers to translate between 3-byte SAD and struct cea_sad,
add ELD helpers to get/set the SADs from/to an ELD.
v2: s/i/sad_index/ (Mitul)
Cc: Mitul Golani <mitulkumar.ajitkumar.golani@intel.com>
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Reviewed-by: Mitul Golani <mitulkumar.ajitkumar.golani@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/8e9a05f2b1e0dd184132d636e1e778e8917ec25d.1698747331.git.jani.nikula@intel.com
The drm_edid.[ch] files are starting to be a bit crowded, and with plans
to add more ELD related functionality, it's perhaps cleanest to split
the ELD code out to a header of its own.
Include drm_eld.h from drm_edid.h for starters, and leave it to
follow-up work to only include drm_eld.h where needed.
Cc: Mitul Golani <mitulkumar.ajitkumar.golani@intel.com>
Reviewed-by: Mitul Golani <mitulkumar.ajitkumar.golani@intel.com>
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/0c6d631fa1058036d72dd25d1cabc90a7c52490e.1698747331.git.jani.nikula@intel.com
The exact behaviour of DSI host controllers is not specified,
therefore define it.
Signed-off-by: Dave Stevenson <dave.stevenson@raspberrypi.com>
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Link: https://lore.kernel.org/r/20221205173328.1395350-7-dave.stevenson@raspberrypi.com
Signed-off-by: Maxime Ripard <maxime@cerno.tech>
This was lost in the code movement done in commit 8ab59da26b
("drm/fb-helper: Move generic fbdev emulation into separate source
file").
Fixes: 8ab59da26b ("drm/fb-helper: Move generic fbdev emulation into separate source file")
Cc: Thomas Zimmermann <tzimmermann@suse.de>
Cc: Javier Martinez Canillas <javierm@redhat.com>
Reviewed-by: Thomas Zimmermann <tzimmermann@suse.de>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Link: https://patchwork.freedesktop.org/patch/msgid/20221107190928.1212116-1-daniel.vetter@ffwll.ch
Rename "FB CMA" helpers to "FB DMA" helpers - considering the hierarchy
of APIs (mm/cma -> dma -> fb dma) calling them "FB DMA" seems to be
more applicable.
Besides that, commit e57924d4ae ("drm/doc: Task to rename CMA helpers")
requests to rename the CMA helpers and implies that people seem to be
confused about the naming.
In order to do this renaming the following script was used:
```
#!/bin/bash
DIRS="drivers/gpu include/drm Documentation/gpu"
REGEX_SYM_UPPER="[0-9A-Z_\-]"
REGEX_SYM_LOWER="[0-9a-z_\-]"
REGEX_GREP_UPPER="(${REGEX_SYM_UPPER}*)(FB)_CMA_(${REGEX_SYM_UPPER}*)"
REGEX_GREP_LOWER="(${REGEX_SYM_LOWER}*)(fb)_cma_(${REGEX_SYM_LOWER}*)"
REGEX_SED_UPPER="s/${REGEX_GREP_UPPER}/\1\2_DMA_\3/g"
REGEX_SED_LOWER="s/${REGEX_GREP_LOWER}/\1\2_dma_\3/g"
# Find all upper case 'CMA' symbols and replace them with 'DMA'.
for ff in $(grep -REHl "${REGEX_GREP_UPPER}" $DIRS)
do
sed -i -E "$REGEX_SED_UPPER" $ff
done
# Find all lower case 'cma' symbols and replace them with 'dma'.
for ff in $(grep -REHl "${REGEX_GREP_LOWER}" $DIRS)
do
sed -i -E "$REGEX_SED_LOWER" $ff
done
# Replace all occurrences of 'CMA' / 'cma' in comments and
# documentation files with 'DMA' / 'dma'.
for ff in $(grep -RiHl " cma " $DIRS)
do
sed -i -E "s/ cma / dma /g" $ff
sed -i -E "s/ CMA / DMA /g" $ff
done
```
Only a few more manual modifications were needed, e.g. reverting the
following modifications in some DRM Kconfig files
- select CMA if HAVE_DMA_CONTIGUOUS
+ select DMA if HAVE_DMA_CONTIGUOUS
as well as manually picking the occurrences of 'CMA'/'cma' in comments and
documentation which relate to "FB CMA", but not "GEM CMA".
This patch is compile-time tested building a x86_64 kernel with
`make allyesconfig && make drivers/gpu/drm`.
Acked-by: Sam Ravnborg <sam@ravnborg.org>
Acked-by: Thomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Danilo Krummrich <dakr@redhat.com>
Reviewed-by: Liviu Dudau <liviu.dudau@arm.com> #drivers/gpu/drm/arm
Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20220802000405.949236-3-dakr@redhat.com
SCDC is the Status and Control Data Channel for HDMI. Move the SCDC
helpers into display/ and split the header into files for core and
helpers. Update all affected drivers. No functional changes.
To avoid the proliferation of Kconfig options, SCDC is part of DRM's
support for HDMI. If necessary, a new option could make SCDC an
independent feature.
Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: Javier Martinez Canillas <javierm@redhat.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20220421073108.19226-9-tzimmermann@suse.de
Move DRM's HDCP helper library into the display/ subdirectory and add
it to DRM's display helpers. Split the header file into core and helpers.
Update all affected drivers. No functional changes.
v3:
* fix Kconfig dependencies
v2:
* fix include statements (Jani, Javier)
* update Kconfig symbols
Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: Javier Martinez Canillas <javierm@redhat.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20220421073108.19226-7-tzimmermann@suse.de
DSC is the Display Stream Compression standard for DisplayPort. Move
the DSC code into display/ and split the header into files for protocol
core and DRM helpers. Adapt all users of the code. No functional
changes.
To avoid the proliferation of Kconfig options, DSC is part of DRM's
support for DisplayPort. If necessary, a new option could make DSC an
independent feature.
Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: Javier Martinez Canillas <javierm@redhat.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20220421073108.19226-6-tzimmermann@suse.de
Move DisplayPort protocol constants and structures into the new
header drm_dp.h, which can be used by DRM core components. The
existing header drm_dp_helper.h now only contains helper code for
graphics drivers. No functional changes.
Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: Lyude Paul <lyude@redhat.com>
Reviewed-by: Javier Martinez Canillas <javierm@redhat.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20220421073108.19226-5-tzimmermann@suse.de
Rename dp/ to display/ to account for additional display-related
helpers, such as HDMI. Update all related include statements. No
functional changes.
Various drivers, such as i915 and amdgpu, use similar naming scheme
by putting code for video-output standards into a local display/
directory. The new directory's name is aligned with this convention.
v2:
* update commit message (Javier)
Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: Lyude Paul <lyude@redhat.com>
Reviewed-by: Javier Martinez Canillas <javierm@redhat.com>
Reviewed-by: Alex Deucher <alexander.deucher@amd.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20220421073108.19226-3-tzimmermann@suse.de
DRM's DisplayPort helpers moved into the subdirectory dp/. Change
the documentation accordingly.
Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Fixes: adb9d5a2cc ("drm/dp: Move DisplayPort helpers into separate helper module")
Acked-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Reported-by: Jani Nikula <jani.nikula@linux.intel.com>
Tested-by: Jani Nikula <jani.nikula@intel.com>
Cc: Thomas Zimmermann <tzimmermann@suse.de>
Cc: Lyude Paul <lyude@redhat.com>
Cc: Daniel Vetter <daniel@ffwll.ch>
Cc: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Cc: Maxime Ripard <mripard@kernel.org>
Cc: dri-devel@lists.freedesktop.org
Link: https://patchwork.freedesktop.org/patch/msgid/20220120113647.22484-1-tzimmermann@suse.de
On some new laptops the LCD panel has a builtin electronic privacy-screen.
We want to export this functionality as a property on the drm connector
object. But often this functionality is not exposed on the GPU but on some
other (ACPI) device.
This commit adds a privacy-screen class allowing the driver for these
other devices to register themselves as a privacy-screen provider; and
allowing the drm/kms code to get a privacy-screen provider associated
with a specific GPU/connector combo.
Changes in v2:
- Make CONFIG_DRM_PRIVACY_SCREEN a bool which controls if the drm_privacy
code gets built as part of the main drm module rather then making it
a tristate which builds its own module.
- Add a #if IS_ENABLED(CONFIG_DRM_PRIVACY_SCREEN) check to
drm_privacy_screen_consumer.h and define stubs when the check fails.
Together these 2 changes fix several dependency issues.
- Remove module related code now that this is part of the main drm.ko
- Use drm_class as class for the privacy-screen devices instead of
adding a separate class for this
Changes in v3:
- Make the static inline drm_privacy_screen_get_state() stub set sw_state
and hw_state to PRIVACY_SCREEN_DISABLED to squelch an uninitialized
variable warning when CONFIG_DRM_PRIVICAY_SCREEN is not set
Changes in v4:
- Make drm_privacy_screen_set_sw_state() skip calling out to the hw if
hw_state == new_sw_state
Reviewed-by: Emil Velikov <emil.l.velikov@gmail.com>
Reviewed-by: Lyude Paul <lyude@redhat.com>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20211005202322.700909-3-hdegoede@redhat.com
Interactions between bridges, panels, MIPI-DSI host and the component
framework are not trivial and can lead to probing issues when
implementing a display driver. Let's document the various cases we need
too consider, and the solution to support all the cases.
Signed-off-by: Maxime Ripard <maxime@cerno.tech>
Reviewed-by: Andrzej Hajda <a.hajda@samsung.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20210910101218.1632297-3-maxime@cerno.tech
The bridge documentation overview is quite packed already, and we'll add
some more documentation that isn't part of an overview at all.
Let's add some sections to the documentation to separate each bits.
Reviewed-by: Andrzej Hajda <a.hajda@samsung.com>
Reviewed-by: Sam Ravnborg <sam@ravnborg.org>
Signed-off-by: Maxime Ripard <maxime@cerno.tech>
Link: https://patchwork.freedesktop.org/patch/msgid/20210910101218.1632297-2-maxime@cerno.tech
Several drivers use GEM buffer objects as shadow buffers for the actual
framebuffer memory. Right now, drivers do these vmap operations in their
commit tail, which is actually not allowed by the locking rules for
the dma-buf reservation lock. The involved BO has to be vmapped in the
plane's prepare_fb callback and vunmapped in cleanup_fb.
This patch introduces atomic helpers for such shadow planes. Plane
functions manage the plane state for shadow planes. The provided
implementations for prepare_fb and cleanup_fb vmap and vunmap all BOs of
struct drm_plane_state.fb. The mappings are afterwards available in the
plane's commit-tail functions.
For now, all rsp drivers use the simple KMS helpers, so we add the plane
callbacks and wrappers for simple KMS. The internal plane functions can
later be exported as needed.
v3:
* documentation fixes
v2:
* make duplicate_state interface compatible with
struct drm_plane_funcs
Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Tested-by: Gerd Hoffmann <kraxel@redhat.com>
Acked-by: Gerd Hoffmann <kraxel@redhat.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20210208115538.6430-4-tzimmermann@suse.de
- 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
Most bridge drivers create a DRM connector to model the connector at the
output of the bridge. This model is historical and has worked pretty
well so far, but causes several issues:
- It prevents supporting more complex display pipelines where DRM
connector operations are split over multiple components. For instance a
pipeline with a bridge connected to the DDC signals to read EDID data,
and another one connected to the HPD signal to detect connection and
disconnection, will not be possible to support through this model.
- It requires every bridge driver to implement similar connector
handling code, resulting in code duplication.
- It assumes that a bridge will either be wired to a connector or to
another bridge, but doesn't support bridges that can be used in both
positions very well (although there is some ad-hoc support for this in
the analogix_dp bridge driver).
In order to solve these issues, ownership of the connector needs to be
moved to the display controller driver.
To avoid code duplication in display controller drivers, add a new
helper to create and manage a DRM connector backed by a chain of
bridges. All connector operations are delegating to the appropriate
bridge in the chain.
Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Reviewed-by: Boris Brezillon <boris.brezillon@collabora.com>
Acked-by: Sam Ravnborg <sam@ravnborg.org>
Tested-by: Sebastian Reichel <sebastian.reichel@collabora.com>
Reviewed-by: Sebastian Reichel <sebastian.reichel@collabora.com>
Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ti.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200226112514.12455-21-laurent.pinchart@ideasonboard.com
Clean up the drm_bridge overview documentation, and expand the
operations documentation to provide more details on API usage.
Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ti.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200226112514.12455-7-laurent.pinchart@ideasonboard.com
Fixes the following warning:
../include/drm/drm_atomic_state_helper.h:1: warning: no structured comments found
Fixes: 9ef8a9dc4b ("drm: Extract drm_atomic_state_helper.[hc]")
Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
Cc: Daniel Vetter <daniel.vetter@intel.com>
Cc: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Cc: Maxime Ripard <mripard@kernel.org>
Cc: Sean Paul <sean@poorly.run>
Cc: David Airlie <airlied@linux.ie>
Cc: Daniel Vetter <daniel@ffwll.ch>
Cc: dri-devel@lists.freedesktop.org
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Sean Paul <seanpaul@chromium.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20191007151921.27099-1-sean@poorly.run
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 <eric@anholt.net>
Cc: David Lechner <david@lechnology.com>
Reviewed-by: Sam Ravnborg <sam@ravnborg.org>
Signed-off-by: Noralf Trønnes <noralf@tronnes.org>
Acked-by: David Lechner <david@lechnology.com>
Acked-by: Eric Anholt <eric@anholt.net>
Link: https://patchwork.freedesktop.org/patch/msgid/20190722104312.16184-9-noralf@tronnes.org
This patch adds a new drm helper library to help drivers implement
self refresh. Drivers choosing to use it will register crtcs and
will receive callbacks when it's time to enter or exit self refresh
mode.
In its current form, it has a timer which will trigger after a
driver-specified amount of inactivity. When the timer triggers, the
helpers will submit a new atomic commit to shut the refreshing pipe
off. On the next atomic commit, the drm core will revert the self
refresh state and bring everything back up to be actively driven.
From the driver's perspective, this works like a regular disable/enable
cycle. The driver need only check the 'self_refresh_active' state in
crtc_state. It should initiate self refresh mode on the panel and enter
an off or low-power state.
Changes in v2:
- s/psr/self_refresh/ (Daniel)
- integrated the psr exit into the commit that wakes it up (Jose/Daniel)
- made the psr state per-crtc (Jose/Daniel)
Changes in v3:
- Remove the self_refresh_(active|changed) from connector state (Daniel)
- Simplify loop in drm_self_refresh_helper_alter_state (Daniel)
- Improve self_refresh_aware comment (Daniel)
- s/self_refresh_state/self_refresh_data/ (Daniel)
Changes in v4:
- Move docbook location below panel (Daniel)
- Improve docbook with references and more detailed explanation (Daniel)
- Instead of register/unregister, use init/cleanup (Daniel)
Changes in v5:
- Resolved conflict in drm_atomic_helper.c #include block
- Resolved conflict in rst with HDCP helper docs
Changes in v6:
- Fix include ordering, clean up forward declarations (Sam)
Link to v1: https://patchwork.freedesktop.org/patch/msgid/20190228210939.83386-2-sean@poorly.run
Link to v2: https://patchwork.freedesktop.org/patch/msgid/20190326204509.96515-1-sean@poorly.run
Link to v3: https://patchwork.freedesktop.org/patch/msgid/20190502194956.218441-6-sean@poorly.run
Link to v4: https://patchwork.freedesktop.org/patch/msgid/20190508160920.144739-6-sean@poorly.run
Link to v5: https://patchwork.freedesktop.org/patch/msgid/20190611160844.257498-6-sean@poorly.run
Cc: Daniel Vetter <daniel@ffwll.ch>
Cc: Jose Souza <jose.souza@intel.com>
Cc: Zain Wang <wzz@rock-chips.com>
Cc: Tomasz Figa <tfiga@chromium.org>
Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
Cc: Sam Ravnborg <sam@ravnborg.org>
Tested-by: Heiko Stuebner <heiko@sntech.de>
Reviewed-by: Daniel Vetter <daniel@ffwll.ch>
Signed-off-by: Sean Paul <seanpaul@chromium.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20190612145026.191846-1-sean@poorly.run
On every hdcp revocation check request SRM is read from fw file
/lib/firmware/display_hdcp_srm.bin
SRM table is parsed and stored at drm_hdcp.c, with functions exported
for the services for revocation check from drivers (which
implements the HDCP authentication)
This patch handles the HDCP1.4 and 2.2 versions of SRM table.
v2:
moved the uAPI to request_firmware_direct() [Daniel]
v3:
kdoc added. [Daniel]
srm_header unified and bit field definitions are removed. [Daniel]
locking improved. [Daniel]
vrl length violation is fixed. [Daniel]
v4:
s/__swab16/be16_to_cpu [Daniel]
be24_to_cpu is done through a global func [Daniel]
Unused variables are removed. [Daniel]
unchecked return values are dropped from static funcs [Daniel]
Signed-off-by: Ramalingam C <ramalingam.c@intel.com>
Acked-by: Satyeshwar Singh <satyeshwar.singh@intel.com>
Reviewed-by: Daniel Vetter <daniel@ffwll.ch>
Acked-by: Dave Airlie <airlied@gmail.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/20190507162745.25600-5-ramalingam.c@intel.com
This adds a library for shmem backed GEM objects.
v8:
- export drm_gem_shmem_create_with_handle
- call mapping_set_gfp_mask to set default zone to GFP_HIGHUSER
- Add helper drm_gem_shmem_get_pages_sgt()
v7:
- Use write-combine for mmap instead. This is the more common
case. (robher)
v6:
- Fix uninitialized variable issue in an error path (anholt).
- Add a drm_gem_shmem_vm_open() to the fops to get proper refcounting
of the pages (anholt).
v5:
- Drop drm_gem_shmem_prime_mmap() (Daniel Vetter)
- drm_gem_shmem_mmap(): Subtract drm_vma_node_start() to get the real
vma->vm_pgoff
- drm_gem_shmem_fault(): Use vmf->pgoff now that vma->vm_pgoff is correct
v4:
- Drop cache modes (Thomas Hellstrom)
- Add a GEM attached vtable
v3:
- Grammar (Sam Ravnborg)
- s/drm_gem_shmem_put_pages_unlocked/drm_gem_shmem_put_pages_locked/
(Sam Ravnborg)
- Add debug output in error path (Sam Ravnborg)
Signed-off-by: Noralf Trønnes <noralf@tronnes.org>
Signed-off-by: Eric Anholt <eric@anholt.net>
Signed-off-by: Rob Herring <robh@kernel.org>
Signed-off-by: Eric Anholt <eric@anholt.net>
Reviewed-by: Eric Anholt <eric@anholt.net>
Link: https://patchwork.freedesktop.org/patch/msgid/20190313004344.24169-1-robh@kernel.org
drm-next has been forwarded to 5.0-rc1, and we need it to apply the damage
helper for dirtyfb series from Noralf Trønnes.
Signed-off-by: Maxime Ripard <maxime.ripard@bootlin.com>
The current way of handling refcounting in the DP MST helpers is really
confusing and probably just plain wrong because it's been hacked up many
times over the years without anyone actually going over the code and
seeing if things could be simplified.
To the best of my understanding, the current scheme works like this:
drm_dp_mst_port and drm_dp_mst_branch both have a single refcount. When
this refcount hits 0 for either of the two, they're removed from the
topology state, but not immediately freed. Both ports and branch devices
will reinitialize their kref once it's hit 0 before actually destroying
themselves. The intended purpose behind this is so that we can avoid
problems like not being able to free a remote payload that might still
be active, due to us having removed all of the port/branch device
structures in memory, as per:
commit 91a25e4631 ("drm/dp/mst: deallocate payload on port destruction")
Which may have worked, but then it caused use-after-free errors. Being
new to MST at the time, I tried fixing it;
commit 263efde31f ("drm/dp/mst: Get validated port ref in drm_dp_update_payload_part1()")
But, that was broken: both drm_dp_mst_port and drm_dp_mst_branch structs
are validated in almost every DP MST helper function. Simply put, this
means we go through the topology and try to see if the given
drm_dp_mst_branch or drm_dp_mst_port is still attached to something
before trying to use it in order to avoid dereferencing freed memory
(something that has happened a LOT in the past with this library).
Because of this it doesn't actually matter whether or not we keep keep
the ports and branches around in memory as that's not enough, because
any function that validates the branches and ports passed to it will
still reject them anyway since they're no longer in the topology
structure. So, use-after-free errors were fixed but payload deallocation
was completely broken.
Two years later, AMD informed me about this issue and I attempted to
come up with a temporary fix, pending a long-overdue cleanup of this
library:
commit c54c7374ff ("drm/dp_mst: Skip validating ports during destruction, just ref")
But then that introduced use-after-free errors, so I quickly reverted
it:
commit 9765635b30 ("Revert "drm/dp_mst: Skip validating ports during destruction, just ref"")
And in the process, learned that there is just no simple fix for this:
the design is just broken. Unfortunately, the usage of these helpers are
quite broken as well. Some drivers like i915 have been smart enough to
avoid accessing any kind of information from MST port structures, but
others like nouveau have assumed, understandably so, that
drm_dp_mst_port structures are normal and can just be accessed at any
time without worrying about use-after-free errors.
After a lot of discussion, me and Daniel Vetter came up with a better
idea to replace all of this.
To summarize, since this is documented far more indepth in the
documentation this patch introduces, we make it so that drm_dp_mst_port
and drm_dp_mst_branch structures have two different classes of
refcounts: topology_kref, and malloc_kref. topology_kref corresponds to
the lifetime of the given drm_dp_mst_port or drm_dp_mst_branch in it's
given topology. Once it hits zero, any associated connectors are removed
and the branch or port can no longer be validated. malloc_kref
corresponds to the lifetime of the memory allocation for the actual
structure, and will always be non-zero so long as the topology_kref is
non-zero. This gives us a way to allow callers to hold onto port and
branch device structures past their topology lifetime, and dramatically
simplifies the lifetimes of both structures. This also finally fixes the
port deallocation problem, properly.
Additionally: since this now means that we can keep ports and branch
devices allocated in memory for however long we need, we no longer need
a significant amount of the port validation that we currently do.
Additionally, there is one last scenario that this fixes, which couldn't
have been fixed properly beforehand:
- CPU1 unrefs port from topology (refcount 1->0)
- CPU2 refs port in topology(refcount 0->1)
Since we now can guarantee memory safety for ports and branches
as-needed, we also can make our main reference counting functions fix
this problem by using kref_get_unless_zero() internally so that topology
refcounts can only ever reach 0 once.
Changes since v4:
* Change the kernel-figure summary for dp-mst/topology-figure-1.dot a
bit - danvet
* Remove figure numbers - danvet
Changes since v3:
* Remove rebase detritus - danvet
* Split out purely style changes into separate patches - hwentlan
Changes since v2:
* Fix commit message - checkpatch
* s/)-1/) - 1/g - checkpatch
Changes since v1:
* Remove forward declarations - danvet
* Move "Branch device and port refcounting" section from documentation
into kernel-doc comments - danvet
* Export internal topology lifetime functions into their own section in
the kernel-docs - danvet
* s/@/&/g for struct references in kernel-docs - danvet
* Drop the "when they are no longer being used" bits from the kernel
docs - danvet
* Modify diagrams to show how the DRM driver interacts with the topology
and payloads - danvet
* Make suggested documentation changes for
drm_dp_mst_topology_get_mstb() and drm_dp_mst_topology_get_port() -
danvet
* Better explain the relationship between malloc refs and topology krefs
in the documentation for drm_dp_mst_topology_get_port() and
drm_dp_mst_topology_get_mstb() - danvet
* Fix "See also" in drm_dp_mst_topology_get_mstb() - danvet
* Rename drm_dp_mst_topology_get_(port|mstb)() ->
drm_dp_mst_topology_try_get_(port|mstb)() and
drm_dp_mst_topology_ref_(port|mstb)() ->
drm_dp_mst_topology_get_(port|mstb)() - danvet
* s/should/must in docs - danvet
* WARN_ON(refcount == 0) in topology_get_(mstb|port) - danvet
* Move kdocs for mstb/port structs inline - danvet
* Split drm_dp_get_last_connected_port_and_mstb() changes into their own
commit - danvet
Signed-off-by: Lyude Paul <lyude@redhat.com>
Reviewed-by: Harry Wentland <harry.wentland@amd.com>
Reviewed-by: Daniel Vetter <daniel@ffwll.ch>
Cc: David Airlie <airlied@redhat.com>
Cc: Jerry Zuo <Jerry.Zuo@amd.com>
Cc: Juston Li <juston.li@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190111005343.17443-7-lyude@redhat.com
According to Display Stream compression spec 1.2, the picture
parameter set metadata is sent from source to sink device
using the DP Secondary data packet. An infoframe is formed
for the PPS SDP header and PPS SDP payload bytes.
This patch adds helpers to fill the PPS SDP header
and PPS SDP payload according to the DSC 1.2 specification.
v7:
* Use BUILD_BUG_ON() to protect changing struct size (Ville)
* Remove typecaseting (Ville)
* Include byteorder.h in drm_dsc.c (Ville)
* Correct kernel doc spacing (Anusha)
v6:
* Use proper sequence points for breaking down the
assignments (Chris Wilson)
* Use SPDX identifier
v5:
Do not use bitfields for DRM structs (Jani N)
v4:
* Use DSC constants for params that dont change across
configurations
v3:
* Add reference to added kernel-docs in
Documentation/gpu/drm-kms-helpers.rst (Daniel Vetter)
v2:
* Add EXPORT_SYMBOL for the drm functions (Manasi)
Cc: dri-devel@lists.freedesktop.org
Cc: Jani Nikula <jani.nikula@linux.intel.com>
Cc: Ville Syrjala <ville.syrjala@linux.intel.com>
Cc: Anusha Srivatsa <anusha.srivatsa@intel.com>
Cc: Harry Wentland <harry.wentland@amd.com>
Signed-off-by: Manasi Navare <manasi.d.navare@intel.com>
Acked-by: Harry Wentland <harry.wentland@amd.com>
Reviewed-by: Anusha Srivatsa <anusha.srivatsa@intel.com>
Acked-by: Sean Paul <seanpaul@chromium.org> (For merging through
drm-intel)
Link: https://patchwork.freedesktop.org/patch/msgid/20181127214125.17658-5-manasi.d.navare@intel.com
We don't want people to accidentally stumble over there.
Also rename the plane helpers to legacy plane helpers. After Ville's
patch to make the clipping helper atomic and move it to
drm_atomic_helper.c there's nothing left in there that should be
useful for modern drivers.
v2: Laurent had a few questions around how state is added to
drm_atomic_state, tried to clarify that. And spotted another sentence
where the docs suggested subclassing.
v3: Small polish (Alex).
Reviewed-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20171214203054.20141-6-daniel.vetter@ffwll.ch
Some x86 clamshell design devices use portrait tablet screens and a display
engine which cannot rotate in hardware, so the firmware just leaves things
as is and we cannot figure out that the display is oriented non upright
from the hardware.
So at least on x86, we need a quirk table for this. This commit adds a DMI
based quirk table which is initially populated with 5 such devices: Asus
T100HA, GPD Pocket, GPD win, I.T.Works TW891 and the VIOS LTH17.
This quirk table will be used by the drm code to let userspace know that
the display is not mounted upright inside the devices case through a new
panel orientation drm-connector property, as well as to tell fbcon to
rotate the console so that it shows the right way up.
Changes in v5:
-Add a kernel-doc comment documenting drm_get_panel_orientation_quirk()
-Remove board_* matches from the dmi-matches for the VIOS LTH17 laptop,
keeping only the (identical) sys_vendor and product_name matches.
This is necessary because an older version of the bios has
board_vendor set to VOIS instead of VIOS
Changes in v6:
-Add reference to added kernel-docs in Documentation/gpu/drm-kms-helpers.rst
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20171125193553.23986-3-hdegoede@redhat.com
This library provides helpers for drivers that don't subclass
drm_framebuffer and are backed by drm_gem_object. The code is
taken from drm_fb_cma_helper.
Signed-off-by: Noralf Trønnes <noralf@tronnes.org>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Reviewed-by: Eric Anholt <eric@anholt.net>
Link: https://patchwork.freedesktop.org/patch/msgid/1502631125-13557-2-git-send-email-noralf@tronnes.org
Many DRM drivers have common code to make a stub connector
implementation that wraps a drm_panel. By wrapping the panel in a DRM
bridge, all of the connector code (including calls during encoder
enable/disable) goes away.
v2: Fix build with CONFIG_DRM=m, drop "dev" argument that should just
be the panel's dev, move kerneldoc up a level and document
_remove().
v3: Fix another breakage with CONFIG_DRM=m, fix breakage with
CONFIG_OF=n, move protos under CONFIG_DRM_PANEL_BRIDGE, wrap a
line.
Signed-off-by: Eric Anholt <eric@anholt.net>
Acked-by: Daniel Vetter <daniel.vetter@ffwll.ch> (v1)
Reviewed-by: Boris Brezillon <boris.brezillon@free-electrons.com> (v2)
Acked-by: Archit Taneja <architt@codeaurora.org> (v2)
Signed-off-by: Archit Taneja <architt@codeaurora.org>
Link: http://patchwork.freedesktop.org/patch/msgid/20170602202514.11900-1-eric@anholt.net
SCDC is a mechanism defined in the HDMI 2.0 specification that allows
the source and sink devices to communicate.
This commit introduces helpers to access the SCDC and provides the
symbolic names for the various registers defined in the specification.
V2: Rebase.
V3: Added R-B from Jose.
V4: Rebase
V5: Addressed review comments from Ville
- Handle the I2c return values in a better way (dp_dual_mode)
- Make the macros for SCDC Major/Minor more readable, by adding
a 'GET' in the macro names
V6: Rebase
V7: Rebase
V8: Rebase
V9: Rebase
V10: Rebase
Signed-off-by: Thierry Reding <treding@nvidia.com>
Signed-off-by: Shashank Sharma <shashank.sharma@intel.com>
Reviewed-by: Jose Abreu <joabreu@synopsys.com>
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1489404244-16608-2-git-send-email-shashank.sharma@intel.com
I want to split up a few more things and document some details better
(like how exactly to subclass drm_atomic_state). And maybe also split
up the helpers a bit per-topic, but this should be a ok-ish start for
better atomic overview.
v2: Spelling and clarifications (Eric).
v3: Implement suggestion from Gabriel to fix the graph.
v4: Review from Laurent.
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Cc: Gabriel Krisman Bertazi <krisman@collabora.co.uk>
Acked-by: Eric Anholt <eric@anholt.net>
Cc: Eric Anholt <eric@anholt.net>
Cc: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Cc: Harry Wentland <harry.wentland@amd.com>
Reviewed-by: Gabriel Krisman Bertazi <krisman@collabora.co.uk>
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20170302151638.1882-6-daniel.vetter@ffwll.ch
First overview text (if there is any), then headers (since generally
you want to start out with the data structures), then all the other
stuff with functions.
Most of this is pre-shpinx, since with the old docbook only the
overview stuff was pulled in directly. Everything else was put in a
per-section index, so include order didn't really matter.
Acked-by: Eric Anholt <eric@anholt.net>
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20170302151638.1882-4-daniel.vetter@ffwll.ch
I totally butcherd the job on typing the kernel-doc for these, and no
one realized. Noticed by Russell. Maarten has a more complete approach
to this confusion, by making it more explicit what the new/old state
is, instead of this magic switching behaviour.
v2:
- Liviu pointed out that wait_for_fences is even more magic. Leave
that as @state, and document @pre_swap better.
- While at it, patch in header for the reference section.
- Fix spelling issues Russell noticed.
v3: Fix up the @pre_swap note (Liviu): Also s/synchronous/blocking/,
since async flip is something else than non-blocking.
Cc: Liviu Dudau <liviu.dudau@arm.com>
Reported-by: Russell King - ARM Linux <linux@armlinux.org.uk>
Cc: Russell King - ARM Linux <linux@armlinux.org.uk>
Fixes: 9f2a7950e7 ("drm/atomic-helper: nonblocking commit support")
Cc: Gustavo Padovan <gustavo.padovan@collabora.co.uk>
Cc: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Cc: Tomeu Vizoso <tomeu.vizoso@gmail.com>
Cc: Daniel Stone <daniels@collabora.com>
Reviewed-by: Liviu Dudau <liviu.dudau@arm.com>
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20161121171802.24147-1-daniel.vetter@ffwll.ch
And also put the overview section into the KMS Properties part of the
docs, instead of randomly-placed within the helpers - this is part of
the uabi.
With this patch I think drm_crtc.[hc] is cleaned up and entirely
documented.
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
While reviewing docs I spotted that we have a few functions that
really just don't fit into their containing helper library section.
Extract them and shovel them all into a new library for random one-off
aux stuff.
v2: Remove wrongly added files for real.
Cc: Sean Paul <seanpaul@chromium.org>
Reviewed-by: Sean Paul <seanpaul@chromium.org>
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1471034937-651-3-git-send-email-daniel.vetter@ffwll.ch
- Move the common vtable stuff to the top
- Move "Tile Group" to a more appropriate heading level
- Throw away the old intro for the crtc helpers (it's entirely stale,
e.g. helpers have become modular years ago), and replace it with a
general intro about the motivation behind helpers.
- Reorder helpers to group them together a bit better, and explain
that grouping in the intro.
- Make sure the introductory DOC section is always first.
v2:
- Remove bogus files accidentally added (Sean).
- Spelling fixes (Sean).
Cc: Sean Paul <seanpaul@chromium.org>
Reviewed-by: Sean Paul <seanpaul@chromium.org>
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1471034937-651-2-git-send-email-daniel.vetter@ffwll.ch
