The current documentation of drm_atomic_state says that it's the "global
state object". This is confusing since, while it does contain all the
objects affected by an update and their respective states, if an object
isn't affected by this update it won't be part of it.
Thus, it's not truly a "global state", unlike object state structures
that do contain the entire state of a given object.
Reviewed-by: Hamza Mahfooz <hamza.mahfooz@amd.com>
Acked-by: Pekka Paalanen <pekka.paalanen@collabora.com>
Link: https://lore.kernel.org/r/20231214100917.277842-4-mripard@kernel.org
Signed-off-by: Maxime Ripard <mripard@kernel.org>
Commits 63e83c1dba ("drm: Consolidate connector arrays in
drm_atomic_state"), b8b5342b69 ("drm: Consolidate plane arrays in
drm_atomic_state") and 5d943aa6c0 ("drm: Consolidate crtc arrays in
drm_atomic_state") moved the object pointer and their state pointer to
an intermediate structure storing both.
The CRTC commit didn't update the doc of the crtcs field to reflect
that, and the doc for the planes and connectors fields mention that they
are pointers to an array of structures with per-$OBJECT data.
The private_objs field was added later on by commit b430c27a7d ("drm:
Add driver-private objects to atomic state") reusing the same sentence
than the crtcs field, probably due to copy and paste.
While these fields are indeed pointers to an array, each item of that
array contain a pointer to the object structure affected by the update,
and its old and new state. There's no per-object data there, and there's
more than just a pointer to the objects.
Let's rephrase those fields a bit to better match the current situation.
Acked-by: Sui Jingfeng <sui.jingfeng@linux.dev>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: https://lore.kernel.org/r/20231214100917.277842-3-mripard@kernel.org
Signed-off-by: Maxime Ripard <mripard@kernel.org>
Add description for parameters for
for_each_new_plane_in_state_reverse to fix warnings:
include/drm/drm_atomic.h:908: warning: Function parameter or member '__state' not described in 'for_each_new_plane_in_state_reverse'
include/drm/drm_atomic.h:908: warning: Function parameter or member 'plane' not described in 'for_each_new_plane_in_state_reverse'
include/drm/drm_atomic.h:908: warning: Function parameter or member 'new_plane_state' not described in 'for_each_new_plane_in_state_reverse'
include/drm/drm_atomic.h:908: warning: Function parameter or member '__i' not described in 'for_each_new_plane_in_state_reverse'
Fixes: a6c3c37b66 ("drm/amd/display: fix gcc set but not used warning of variable 'old_plane_state'")
Signed-off-by: Yu Kuai <yukuai3@huawei.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
define a new macro for_each_new_plane_in_state_reverse to replace
for_each_oldnew_plane_in_state_reverse, so that the unused variable
'old_plane_state' can be removed.
Fix gcc warning:
drivers/gpu/drm/amd/amdgpu/../display/amdgpu_dm/amdgpu_dm.c:10066:26: warning:
variable ‘old_plane_state’ set but not used [-Wunused-but-set-variable]
Signed-off-by: Yu Kuai <yukuai3@huawei.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
drm_bridge_state is extended to describe the input and output bus
configurations. These bus configurations are exposed through the
drm_bus_cfg struct which encodes the configuration of a physical
bus between two components in an output pipeline, usually between
two bridges, an encoder and a bridge, or a bridge and a connector.
The bus configuration is stored in drm_bridge_state separately for
the input and output buses, as seen from the point of view of each
bridge. The bus configuration of a bridge output is usually identical
to the configuration of the next bridge's input, but may differ if
the signals are modified between the two bridges, for instance by an
inverter on the board. The input and output configurations of a
bridge may differ if the bridge modifies the signals internally,
for instance by performing format conversion, or*modifying signals
polarities.
Bus format negotiation is automated by the core, drivers just have
to implement the ->atomic_get_{output,input}_bus_fmts() hooks if they
want to take part to this negotiation. Negotiation happens in reverse
order, starting from the last element of the chain (the one directly
connected to the display) up to the first element of the chain (the one
connected to the encoder).
During this negotiation all supported formats are tested until we find
one that works, meaning that the formats array should be in decreasing
preference order (assuming the driver has a preference order).
Note that the bus format negotiation works even if some elements in the
chain don't implement the ->atomic_get_{output,input}_bus_fmts() hooks.
In that case, the core advertises only MEDIA_BUS_FMT_FIXED and lets
the previous bridge element decide what to do (most of the time, bridge
drivers will pick a default bus format or extract this piece of
information from somewhere else, like a FW property).
v10:
* Add changelog to the commit message
v9:
* No changes
v8:
* Fix a test in drm_atomic_bridge_chain_select_bus_fmts() (Reported by
Jonas)
v7:
* Adapt the code to deal with the fact that not all bridges in the
chain have a bridge state
v5 -> v6:
* No changes
v4:
* Enhance the doc
* Fix typos
* Rename some parameters/fields
* Reword the commit message
v3:
* Fix the commit message (Reported by Laurent)
* Document the fact that bus formats should not be directly modified by
drivers (Suggested by Laurent)
* Document the fact that format order matters (Suggested by Laurent)
* Propagate bus flags by default
* Document the fact that drivers can tweak bus flags if needed
* Let ->atomic_get_{output,input}_bus_fmts() allocate the bus format
array (Suggested by Laurent)
* Add a drm_atomic_helper_bridge_propagate_bus_fmt()
* Mandate that bridge drivers return accurate input_fmts even if they
are known to be the first element in the bridge chain
v2:
* Rework things to support more complex use cases
Signed-off-by: Boris Brezillon <boris.brezillon@collabora.com>
Signed-off-by: Neil Armstrong <narmstrong@baylibre.com>
[narmstrong: fixed doc in include/drm/drm_bridge.h:69 fmt->format]
Reviewed-by: Jernej Skrabec <jernej.skrabec@siol.net>
Tested-by: Jonas Karlman <jonas@kwiboo.se>
Link: https://patchwork.freedesktop.org/patch/msgid/20200128135514.108171-7-boris.brezillon@collabora.com
One of the last remaining objects to not have its atomic state.
This is being motivated by our attempt to support runtime bus-format
negotiation between elements of the bridge chain.
This patch just paves the road for such a feature by adding a new
drm_bridge_state object inheriting from drm_private_obj so we can
re-use some of the existing state initialization/tracking logic.
v10:
* Add changelog to the commit message
v9:
* Clarify the fact that the bridge->atomic_reset() and
{connector,plane,crtc,...}->reset() semantics are different
* Move the drm_atomic_private_obj_init() call back to
drm_bridge_attach()
* Check the presence of ->atomic_duplicate_state instead of
->atomic_reset in drm_atomic_add_encoder_bridges()
* Fix copy&paste errors in the atomic bridge state helpers doc
* Add A-b/R-b tags
v8:
* Move bridge state helpers out of the CONFIG_DEBUGFS section
v7:
* Move helpers, struct-defs, ... to atomic helper files to avoid the
drm -> drm_kms_helper -> drm circular dep
* Stop providing default implementation for atomic state reset,
duplicate and destroy hooks (has to do with the helper/core split)
* Drop all R-b/T-b as helpers have now be moved to other places
v6:
* Made helpers private, removed doc and moved them to satisfy dependencies
* Renamed helpers to _default_
v5:
* Re-introduced the helpers from v4
v4:
* Fix the doc
* Kill default helpers (inlined)
* Fix drm_atomic_get_bridge_state() to check for an ERR_PTR()
* Add Neil's R-b
v3:
* No changes
v2:
* Use drm_for_each_bridge_in_chain()
* Rename helpers to be more consistent with the rest of the DRM API
* Improve/fix the doc
Signed-off-by: Boris Brezillon <boris.brezillon@collabora.com>
Signed-off-by: Neil Armstrong <narmstrong@baylibre.com>
Reviewed-by: Neil Armstrong <narmstrong@baylibre.com>
Acked-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/20200128135514.108171-2-boris.brezillon@collabora.com
