linux/include/drm/drm_atomic_helper.h

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drm: Add atomic/plane helpers This is the first cut of atomic helper code. As-is it's only useful to implement a pure atomic interface for plane updates. Later patches will integrate this with the crtc helpers so that full atomic updates are possible. We also need a pile of helpers to aid drivers in transitioning from the legacy world to the shiny new atomic age. Finally we need helpers to implement legacy ioctls on top of the atomic interface. The design of the overall helpers<->driver interaction is fairly simple, but has an unfortunate large interface: - We have ->atomic_check callbacks for crtcs and planes. The idea is that connectors don't need any checking, and if they do they can adjust the relevant crtc driver-private state. So no connector hooks should be needed. Also the crtc helpers integration will do the ->best_encoder checks, so no need for that. - Framebuffer pinning needs to be done before we can commit to the hw state. This is especially important for async updates where we must pin all buffers before returning to userspace, so that really only hw failures can happen in the asynchronous worker. Hence we add ->prepare_fb and ->cleanup_fb hooks for this resources management. - The actual atomic plane commit can't fail (except hw woes), so has void return type. It has three stages: 1. Prepare all affected crtcs with crtc->atomic_begin. Drivers can use this to unset the GO bit or similar latches to prevent plane updates. 2. Update plane state by looping over all changed planes and calling plane->atomic_update. Presuming the hardware is sane and has GO bits drivers can simply bash the state into the hardware in this function. Other drivers might use this to precompute hw state for the final step. 3. Finally latch the update for the next vblank with crtc->atomic_flush. Note that this function doesn't need to wait for the vblank to happen even for the synchronous case. v2: Clear drm_<obj>_state->state to NULL when swapping in state. v3: Add TODO that we don't short-circuit plane updates for now. Likely no one will care. v4: Squash in a bit of polish that somehow landed in the wrong (later) patche. v5: Integrate atomic functions into the drm docbook and fixup the kerneldoc. v6: Fixup fixup patch squashing fumble. v7: Don't touch the legacy plane state plane->fb and plane->crtc. This is only used by the legacy ioctl code in the drm core, and that code already takes care of updating the pointers in all relevant cases. This is in stark contrast to connector->encoder->crtc links on the modeset side, which we still need to set since the core doesn't touch them. Also some more kerneldoc polish. v8: Drop outdated comment. v9: Handle the state->state pointer correctly: Only clearing the ->state pointer when assigning the state to the kms object isn't good enough. We also need to re-link the swapped out state into the drm_atomic_state structure. v10: Shuffle the misplaced docbook template hunk around that Sean spotted. Cc: Sean Paul <seanpaul@chromium.org> Reviewed-by: Sean Paul <seanpaul@chromium.org> Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2014-11-04 23:14:14 +00:00
/*
* Copyright (C) 2014 Red Hat
* Copyright (C) 2014 Intel Corp.
*
* Permission is hereby granted, free of charge, to any person obtaining a
* copy of this software and associated documentation files (the "Software"),
* to deal in the Software without restriction, including without limitation
* the rights to use, copy, modify, merge, publish, distribute, sublicense,
* and/or sell copies of the Software, and to permit persons to whom the
* Software is furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included in
* all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
* THE COPYRIGHT HOLDER(S) OR AUTHOR(S) BE LIABLE FOR ANY CLAIM, DAMAGES OR
* OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
* ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
* OTHER DEALINGS IN THE SOFTWARE.
*
* Authors:
* Rob Clark <robdclark@gmail.com>
* Daniel Vetter <daniel.vetter@ffwll.ch>
*/
#ifndef DRM_ATOMIC_HELPER_H_
#define DRM_ATOMIC_HELPER_H_
#include <drm/drm_crtc.h>
#include <drm/drm_modeset_helper_vtables.h>
#include <drm/drm_modeset_helper.h>
struct drm_atomic_state;
struct drm_private_obj;
struct drm_private_state;
int drm_atomic_helper_check_modeset(struct drm_device *dev,
struct drm_atomic_state *state);
int drm_atomic_helper_check_planes(struct drm_device *dev,
struct drm_atomic_state *state);
drm: Add atomic/plane helpers This is the first cut of atomic helper code. As-is it's only useful to implement a pure atomic interface for plane updates. Later patches will integrate this with the crtc helpers so that full atomic updates are possible. We also need a pile of helpers to aid drivers in transitioning from the legacy world to the shiny new atomic age. Finally we need helpers to implement legacy ioctls on top of the atomic interface. The design of the overall helpers<->driver interaction is fairly simple, but has an unfortunate large interface: - We have ->atomic_check callbacks for crtcs and planes. The idea is that connectors don't need any checking, and if they do they can adjust the relevant crtc driver-private state. So no connector hooks should be needed. Also the crtc helpers integration will do the ->best_encoder checks, so no need for that. - Framebuffer pinning needs to be done before we can commit to the hw state. This is especially important for async updates where we must pin all buffers before returning to userspace, so that really only hw failures can happen in the asynchronous worker. Hence we add ->prepare_fb and ->cleanup_fb hooks for this resources management. - The actual atomic plane commit can't fail (except hw woes), so has void return type. It has three stages: 1. Prepare all affected crtcs with crtc->atomic_begin. Drivers can use this to unset the GO bit or similar latches to prevent plane updates. 2. Update plane state by looping over all changed planes and calling plane->atomic_update. Presuming the hardware is sane and has GO bits drivers can simply bash the state into the hardware in this function. Other drivers might use this to precompute hw state for the final step. 3. Finally latch the update for the next vblank with crtc->atomic_flush. Note that this function doesn't need to wait for the vblank to happen even for the synchronous case. v2: Clear drm_<obj>_state->state to NULL when swapping in state. v3: Add TODO that we don't short-circuit plane updates for now. Likely no one will care. v4: Squash in a bit of polish that somehow landed in the wrong (later) patche. v5: Integrate atomic functions into the drm docbook and fixup the kerneldoc. v6: Fixup fixup patch squashing fumble. v7: Don't touch the legacy plane state plane->fb and plane->crtc. This is only used by the legacy ioctl code in the drm core, and that code already takes care of updating the pointers in all relevant cases. This is in stark contrast to connector->encoder->crtc links on the modeset side, which we still need to set since the core doesn't touch them. Also some more kerneldoc polish. v8: Drop outdated comment. v9: Handle the state->state pointer correctly: Only clearing the ->state pointer when assigning the state to the kms object isn't good enough. We also need to re-link the swapped out state into the drm_atomic_state structure. v10: Shuffle the misplaced docbook template hunk around that Sean spotted. Cc: Sean Paul <seanpaul@chromium.org> Reviewed-by: Sean Paul <seanpaul@chromium.org> Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2014-11-04 23:14:14 +00:00
int drm_atomic_helper_check(struct drm_device *dev,
struct drm_atomic_state *state);
drm/atomic-helper: nonblocking commit support Design ideas: - split up the actual commit into different phases, and have completions for each of them. This will be useful for the future when we want to interleave phases much more aggressively, for e.g. queue depth > 1. For not it's just a minimal optimization compared to current common nonblocking implementation patterns from drivers, which all stall for the entire commit to complete, including vblank waits and cleanups. - Extract a separate atomic_commit_hw hook since that's the part most drivers will need to overwrite, hopefully allowing even more shared code. - Enforce EBUSY seamntics by attaching one of the completions to the flip_done vblank event. Side benefit of forcing atomic drivers using these helpers to implement event handlign at least semi-correct. I'm evil that way ;-) - Ridiculously modular, as usual. - The main tracking unit for a commit stays struct drm_atomic_state, and the ownership rules for that are unchanged. Ownership still gets transferred to the driver (and subsequently to the worker) on successful commits. What is added is a small, per-crtc, refcounted structure to track pending commits called struct drm_crtc_commit. No actual state is attached to that though, it's purely for ordering and waiting. - Dependencies are implicitly handled by assuming that any CRTC part of &drm_atomic_state is a dependency, and that the current commit must wait for any commits to complete on those CRTC. This way drivers can easily add more depencies using drm_atomic_get_crtc_state(), which is very natural since in most case a dependency exists iff there's some bit of state that needs to be cross checked. Removing depencies is not possible, drivers simply need to be careful to not include every CRTC in a commit if that's not necessary. Which is a good idea anyway, since that also avoids ww_mutex lock contention. - Queue depth > 1 sees some prep work in this patch by adding a stall paramater to drm_atomic_helper_swap_states(). To be able to push commits entirely free-standing and in a deeper queue through the back-end the driver must not access any obj->state pointers. This means we need to track the old state in drm_atomic_state (much easier with the consolidated arrays), and pass them all explicitly to driver backends (this will be serious amounts of churn). Once that's done stall can be set to false in swap_states. v2: Dont ask for flip_done signalling when the CRTC is off and stays off: Drivers don't handle events in that case. Instead complete right away. This way future commits don't need to have special-case logic, but can keep blocking for the flip_done completion. v3: Tons of fixes: - Stall for preceeding commit for real, not the current one by accident. - Add WARN_ON in case drivers don't fire the drm event. - Don't double-free drm events. v4: Make legacy cursor not stall. v5: Extend the helper hook to cover the entire commit tail. Some drivers need special code for cleanup and vblank waiting, this makes it a bit more useful. Inspired by the rockchip driver. v6: Add WARN_ON to catch drivers who forget to send out the drm event. v7: Fixup the stalls in swap_state for real!! v8: - Fixup trailing whitespace, spotted by Maarten. - Actually wait for flip_done in cleanup_done, like the comment says we should do. Thanks a lot for Tomeu for helping with debugging this on. v9: Now with awesome kerneldoc! v10: Split out drm_crtc_commit tracking infrastructure. v: - Add missing static (Gustavo). - Split out the sync functions, only do the actual nonblocking logic in this patch (Maarten). Cc: Gustavo Padovan <gustavo.padovan@collabora.co.uk> Tested-by: Tomeu Vizoso <tomeu.vizoso@collabora.com> Cc: Maarten Lankhorst <maarten.lankhorst@linux.intel.com> Cc: Tomeu Vizoso <tomeu.vizoso@gmail.com> Cc: Daniel Stone <daniels@collabora.com> Tested-by: Liviu Dudau <Liviu.Dudau@arm.com> Reviewed-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com> Testcase: igt/kms_flip/* Testcase: igt/kms_cursor* Testcase: igt/kms*plane* Signed-off-by: Daniel Vetter <daniel.vetter@intel.com> Link: http://patchwork.freedesktop.org/patch/msgid/1465388359-8070-10-git-send-email-daniel.vetter@ffwll.ch
2016-06-08 12:19:02 +00:00
void drm_atomic_helper_commit_tail(struct drm_atomic_state *state);
void drm_atomic_helper_commit_tail_rpm(struct drm_atomic_state *state);
drm: Atomic crtc/connector updates using crtc/plane helper interfaces So this is finally the integration of the crtc and plane helper interfaces into the atomic helper functions. In the check function we now have a few steps: - First we update the output routing and figure out which crtcs need a full mode set. Suitable encoders are selected using ->best_encoder, with the same semantics as the crtc helpers of implicitly disabling all connectors currently using the encoder. - Then we pull all other connectors into the state update which feed from a crtc which changes. This must be done do catch mode changes and similar updates - atomic updates are differences on top of the current state. - Then we call all the various ->mode_fixup to compute the adjusted mode. Note that here we have a slight semantic difference compared to the crtc helpers: We have not yet updated the encoder->crtc link when calling the encoder's ->mode_fixup function. But that's a requirement when converting to atomic since we want to prepare the entire state completely contained with the over drm_atomic_state structure. So this must be carefully checked when converting drivers over to atomic helpers. - Finally we do call the atomic_check functions on planes and crtcs. The commit function is also quite a beast: - The only step that can fail is done first, namely pinning the framebuffers. After that we cross the point of no return, an async commit would push all that into the worker thread. - The disabling of encoders and connectors is a bit tricky, since depending upon the final state we need to select different crtc helper functions. - Software tracking is a bit clarified compared to the crtc helpers: We commit the software state before starting to touch the hardware, like crtc helpers. But since we just swap them we still have the old state (i.e. the current hw state) around, which is really handy to write simple disable functions. So no more drm_crtc_helper_disable_all_unused_functions kind of fun because we're leaving unused crtcs/encoders behind. Everything gets shut down in-order now, which is one of the key differences of the i915 helpers compared to crtc helpers and a really nice additional guarantee. - Like with the plane helpers the atomic commit function waits for one vblank to pass before calling the framebuffer cleanup function. Compared to Rob's helper approach there's a bunch of upsides: - All the interfaces which can fail are called in the ->check hook (i.e. ->best_match and the various ->mode_fixup hooks). This means that drivers can just reuse those functions and don't need to move everything into ->atomic_check callbacks. If drivers have no need for additional constraint checking beyong their existing crtc helper callbacks they don't need to do anything. - The actual commit operation is properly stage: First we prepare framebuffers, which can potentially still fail (due to memory exhausting). This is important for the async case, where this must be done synchronously to correctly return errors. - The output configuration changes (done with crtc helper functions) and the plane update (using atomic plane helpers) are correctly interleaved: First we shut down any crtcs that need changing, then we update planes and finally we enable everything again. Hardware without GO bits must be more careful with ordering, which this sequence enables. - Also for hardware with shared output resources (like display PLLs) we first must shut down the old configuration before we can enable the new one. Otherwise we can hit an impossible intermediate state where there's not enough PLLs (which is the point behind atomic updates). v2: - Ensure that users of ->check update crtc_state->enable correctly. - Update the legacy state in crtc/plane structures. Eventually we want to remove that, but for now the drm core still expects this (especially the plane->fb pointer). v3: A few changes for better async handling: - Reorder the software side state commit so that it happens all before we touch the hardware. This way async support becomes very easy since we can punt all the actual hw touching to a worker thread. And as long as we synchronize with that thread (flushing or cancelling, depending upon what the driver can handle) before we commit the next software state there's no need for any locking in the worker thread at all. Which greatly simplifies things. And as long as we synchronize with all relevant threads we can have a lot of them (e.g. per-crtc for per-crtc updates) running in parallel. - Expose pre/post plane commit steps separately. We need to expose the actual hw commit step anyway for drivers to be able to implement asynchronous commit workers. But if we expose pre/post and plane commit steps individually we allow drivers to selectively use atomic helpers. - I've forgotten to call encoder/bridge ->mode_set functions, fix this. v4: Add debug output and fix a mixup between current and new state that resulted in crtcs not getting updated correctly. And in an Oops ... v5: - Be kind to driver writers in the vblank wait functions.. if thing aren't working yet, and vblank irq will never come, then let's not block forever.. especially under console-lock. - Correctly clear connector_state->best_encoder when disabling. Spotted while trying to understand a report from Rob Clark. - Only steal encoder if it actually changed, otherwise hilarity ensues if we steal from the current connector and so set the ->crtc pointer unexpectedly to NULL. Reported by Rob Clark. - Bail out in disable_outputs if an output currently doesn't have a best_encoder - this means it's already disabled. v6: Fixupe kerneldoc as reported by Paulo. And also fix up kerneldoc in drm_crtc.h. v7: Take ownership of the atomic state and clean it up with drm_atomic_state_free(). v8 Various improvements all over: - Polish code comments and kerneldoc. - Improve debug output to make sure all failure cases are logged. - Treat enabled crtc with no connectors as invalid input from userspace. - Don't ignore the return value from mode_fixup(). v9: - Improve debug output for crtc_state->mode_changed. v10: - Fixup the vblank waiting code to properly balance the vblank_get/put calls. - Better comments when checking/computing crtc->mode_changed v11: Fixup the encoder stealing logic: We can't look at encoder->crtc since that's not in the atomic state structures and might be updated asynchronously in and async commit. Instead we need to inspect all the connector states and check whether the encoder is currently in used and if so, on which crtc. v12: Review from Sean: - A few spelling fixes. - Flatten control flow indent by converting if blocks to early continue/return in 2 places. - Capture connectors_for_crtc return value in int num_connectors instead of bool has_connectors and do an explicit int->bool conversion with !!. I think the helper is more useful for drivers if it returns the number of connectors (e.g. to detect cloning configurations), so decided to keep that return value. Cc: Sean Paul <seanpaul@chromium.org> Cc: Paulo Zanoni <przanoni@gmail.com> Cc: Rob Clark <robdclark@gmail.com> Reviewed-by: Sean Paul <seanpaul@chromium.org> Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2014-09-16 15:50:47 +00:00
int drm_atomic_helper_commit(struct drm_device *dev,
struct drm_atomic_state *state,
bool nonblock);
drm/atomic: initial support for asynchronous plane update In some cases, like cursor updates, it is interesting to update the plane in an asynchronous fashion to avoid big delays. The current queued update could be still waiting for a fence to signal and thus block any subsequent update until its scan out. In cases like this if we update the cursor synchronously through the atomic API it will cause significant delays that would even be noticed by the final user. This patch creates a fast path to jump ahead the current queued state and do single planes updates without going through all atomic steps in drm_atomic_helper_commit(). We take this path for legacy cursor updates. For now only single plane updates are supported, but we plan to support multiple planes updates and async PageFlips through this interface as well in the near future. v6: - move check code to drm_atomic_helper.c (Daniel Vetter) v5: - improve comments (Eric Anholt) v4: - fix state->crtc NULL check (Archit Taneja) v3: - fix iteration on the wrong crtc state - put back code to forbid updates if there is a queued update for the same plane (Ville Syrjälä) - move size checks back to drivers (Ville Syrjälä) - move ASYNC_UPDATE flag addition to its own patch (Ville Syrjälä) v2: - allow updates even if there is a queued update for the same plane. - fixes on the documentation (Emil Velikov) - unconditionally call ->atomic_async_update (Emil Velikov) - check for ->atomic_async_update earlier (Daniel Vetter) - make ->atomic_async_check() the last step (Daniel Vetter) - add ASYNC_UPDATE flag (Eric Anholt) - update state in core after ->atomic_async_update (Eric Anholt) - update docs (Eric Anholt) Cc: Daniel Vetter <daniel.vetter@intel.com> Cc: Rob Clark <robdclark@gmail.com> Cc: Eric Anholt <eric@anholt.net> Signed-off-by: Gustavo Padovan <gustavo.padovan@collabora.com> Reviewed-by: Archit Taneja <architt@codeaurora.org> (v5) Acked-by: Eric Anholt <eric@anholt.net> (v5) Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch> Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch> Link: http://patchwork.freedesktop.org/patch/msgid/20170630180322.29007-2-gustavo@padovan.org
2017-06-30 18:03:17 +00:00
int drm_atomic_helper_async_check(struct drm_device *dev,
struct drm_atomic_state *state);
void drm_atomic_helper_async_commit(struct drm_device *dev,
struct drm_atomic_state *state);
drm: Atomic crtc/connector updates using crtc/plane helper interfaces So this is finally the integration of the crtc and plane helper interfaces into the atomic helper functions. In the check function we now have a few steps: - First we update the output routing and figure out which crtcs need a full mode set. Suitable encoders are selected using ->best_encoder, with the same semantics as the crtc helpers of implicitly disabling all connectors currently using the encoder. - Then we pull all other connectors into the state update which feed from a crtc which changes. This must be done do catch mode changes and similar updates - atomic updates are differences on top of the current state. - Then we call all the various ->mode_fixup to compute the adjusted mode. Note that here we have a slight semantic difference compared to the crtc helpers: We have not yet updated the encoder->crtc link when calling the encoder's ->mode_fixup function. But that's a requirement when converting to atomic since we want to prepare the entire state completely contained with the over drm_atomic_state structure. So this must be carefully checked when converting drivers over to atomic helpers. - Finally we do call the atomic_check functions on planes and crtcs. The commit function is also quite a beast: - The only step that can fail is done first, namely pinning the framebuffers. After that we cross the point of no return, an async commit would push all that into the worker thread. - The disabling of encoders and connectors is a bit tricky, since depending upon the final state we need to select different crtc helper functions. - Software tracking is a bit clarified compared to the crtc helpers: We commit the software state before starting to touch the hardware, like crtc helpers. But since we just swap them we still have the old state (i.e. the current hw state) around, which is really handy to write simple disable functions. So no more drm_crtc_helper_disable_all_unused_functions kind of fun because we're leaving unused crtcs/encoders behind. Everything gets shut down in-order now, which is one of the key differences of the i915 helpers compared to crtc helpers and a really nice additional guarantee. - Like with the plane helpers the atomic commit function waits for one vblank to pass before calling the framebuffer cleanup function. Compared to Rob's helper approach there's a bunch of upsides: - All the interfaces which can fail are called in the ->check hook (i.e. ->best_match and the various ->mode_fixup hooks). This means that drivers can just reuse those functions and don't need to move everything into ->atomic_check callbacks. If drivers have no need for additional constraint checking beyong their existing crtc helper callbacks they don't need to do anything. - The actual commit operation is properly stage: First we prepare framebuffers, which can potentially still fail (due to memory exhausting). This is important for the async case, where this must be done synchronously to correctly return errors. - The output configuration changes (done with crtc helper functions) and the plane update (using atomic plane helpers) are correctly interleaved: First we shut down any crtcs that need changing, then we update planes and finally we enable everything again. Hardware without GO bits must be more careful with ordering, which this sequence enables. - Also for hardware with shared output resources (like display PLLs) we first must shut down the old configuration before we can enable the new one. Otherwise we can hit an impossible intermediate state where there's not enough PLLs (which is the point behind atomic updates). v2: - Ensure that users of ->check update crtc_state->enable correctly. - Update the legacy state in crtc/plane structures. Eventually we want to remove that, but for now the drm core still expects this (especially the plane->fb pointer). v3: A few changes for better async handling: - Reorder the software side state commit so that it happens all before we touch the hardware. This way async support becomes very easy since we can punt all the actual hw touching to a worker thread. And as long as we synchronize with that thread (flushing or cancelling, depending upon what the driver can handle) before we commit the next software state there's no need for any locking in the worker thread at all. Which greatly simplifies things. And as long as we synchronize with all relevant threads we can have a lot of them (e.g. per-crtc for per-crtc updates) running in parallel. - Expose pre/post plane commit steps separately. We need to expose the actual hw commit step anyway for drivers to be able to implement asynchronous commit workers. But if we expose pre/post and plane commit steps individually we allow drivers to selectively use atomic helpers. - I've forgotten to call encoder/bridge ->mode_set functions, fix this. v4: Add debug output and fix a mixup between current and new state that resulted in crtcs not getting updated correctly. And in an Oops ... v5: - Be kind to driver writers in the vblank wait functions.. if thing aren't working yet, and vblank irq will never come, then let's not block forever.. especially under console-lock. - Correctly clear connector_state->best_encoder when disabling. Spotted while trying to understand a report from Rob Clark. - Only steal encoder if it actually changed, otherwise hilarity ensues if we steal from the current connector and so set the ->crtc pointer unexpectedly to NULL. Reported by Rob Clark. - Bail out in disable_outputs if an output currently doesn't have a best_encoder - this means it's already disabled. v6: Fixupe kerneldoc as reported by Paulo. And also fix up kerneldoc in drm_crtc.h. v7: Take ownership of the atomic state and clean it up with drm_atomic_state_free(). v8 Various improvements all over: - Polish code comments and kerneldoc. - Improve debug output to make sure all failure cases are logged. - Treat enabled crtc with no connectors as invalid input from userspace. - Don't ignore the return value from mode_fixup(). v9: - Improve debug output for crtc_state->mode_changed. v10: - Fixup the vblank waiting code to properly balance the vblank_get/put calls. - Better comments when checking/computing crtc->mode_changed v11: Fixup the encoder stealing logic: We can't look at encoder->crtc since that's not in the atomic state structures and might be updated asynchronously in and async commit. Instead we need to inspect all the connector states and check whether the encoder is currently in used and if so, on which crtc. v12: Review from Sean: - A few spelling fixes. - Flatten control flow indent by converting if blocks to early continue/return in 2 places. - Capture connectors_for_crtc return value in int num_connectors instead of bool has_connectors and do an explicit int->bool conversion with !!. I think the helper is more useful for drivers if it returns the number of connectors (e.g. to detect cloning configurations), so decided to keep that return value. Cc: Sean Paul <seanpaul@chromium.org> Cc: Paulo Zanoni <przanoni@gmail.com> Cc: Rob Clark <robdclark@gmail.com> Reviewed-by: Sean Paul <seanpaul@chromium.org> Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2014-09-16 15:50:47 +00:00
int drm_atomic_helper_wait_for_fences(struct drm_device *dev,
struct drm_atomic_state *state,
bool pre_swap);
void drm_atomic_helper_wait_for_vblanks(struct drm_device *dev,
struct drm_atomic_state *old_state);
void drm_atomic_helper_wait_for_flip_done(struct drm_device *dev,
struct drm_atomic_state *old_state);
void
drm_atomic_helper_update_legacy_modeset_state(struct drm_device *dev,
struct drm_atomic_state *old_state);
void drm_atomic_helper_commit_modeset_disables(struct drm_device *dev,
struct drm_atomic_state *state);
void drm_atomic_helper_commit_modeset_enables(struct drm_device *dev,
drm: Atomic crtc/connector updates using crtc/plane helper interfaces So this is finally the integration of the crtc and plane helper interfaces into the atomic helper functions. In the check function we now have a few steps: - First we update the output routing and figure out which crtcs need a full mode set. Suitable encoders are selected using ->best_encoder, with the same semantics as the crtc helpers of implicitly disabling all connectors currently using the encoder. - Then we pull all other connectors into the state update which feed from a crtc which changes. This must be done do catch mode changes and similar updates - atomic updates are differences on top of the current state. - Then we call all the various ->mode_fixup to compute the adjusted mode. Note that here we have a slight semantic difference compared to the crtc helpers: We have not yet updated the encoder->crtc link when calling the encoder's ->mode_fixup function. But that's a requirement when converting to atomic since we want to prepare the entire state completely contained with the over drm_atomic_state structure. So this must be carefully checked when converting drivers over to atomic helpers. - Finally we do call the atomic_check functions on planes and crtcs. The commit function is also quite a beast: - The only step that can fail is done first, namely pinning the framebuffers. After that we cross the point of no return, an async commit would push all that into the worker thread. - The disabling of encoders and connectors is a bit tricky, since depending upon the final state we need to select different crtc helper functions. - Software tracking is a bit clarified compared to the crtc helpers: We commit the software state before starting to touch the hardware, like crtc helpers. But since we just swap them we still have the old state (i.e. the current hw state) around, which is really handy to write simple disable functions. So no more drm_crtc_helper_disable_all_unused_functions kind of fun because we're leaving unused crtcs/encoders behind. Everything gets shut down in-order now, which is one of the key differences of the i915 helpers compared to crtc helpers and a really nice additional guarantee. - Like with the plane helpers the atomic commit function waits for one vblank to pass before calling the framebuffer cleanup function. Compared to Rob's helper approach there's a bunch of upsides: - All the interfaces which can fail are called in the ->check hook (i.e. ->best_match and the various ->mode_fixup hooks). This means that drivers can just reuse those functions and don't need to move everything into ->atomic_check callbacks. If drivers have no need for additional constraint checking beyong their existing crtc helper callbacks they don't need to do anything. - The actual commit operation is properly stage: First we prepare framebuffers, which can potentially still fail (due to memory exhausting). This is important for the async case, where this must be done synchronously to correctly return errors. - The output configuration changes (done with crtc helper functions) and the plane update (using atomic plane helpers) are correctly interleaved: First we shut down any crtcs that need changing, then we update planes and finally we enable everything again. Hardware without GO bits must be more careful with ordering, which this sequence enables. - Also for hardware with shared output resources (like display PLLs) we first must shut down the old configuration before we can enable the new one. Otherwise we can hit an impossible intermediate state where there's not enough PLLs (which is the point behind atomic updates). v2: - Ensure that users of ->check update crtc_state->enable correctly. - Update the legacy state in crtc/plane structures. Eventually we want to remove that, but for now the drm core still expects this (especially the plane->fb pointer). v3: A few changes for better async handling: - Reorder the software side state commit so that it happens all before we touch the hardware. This way async support becomes very easy since we can punt all the actual hw touching to a worker thread. And as long as we synchronize with that thread (flushing or cancelling, depending upon what the driver can handle) before we commit the next software state there's no need for any locking in the worker thread at all. Which greatly simplifies things. And as long as we synchronize with all relevant threads we can have a lot of them (e.g. per-crtc for per-crtc updates) running in parallel. - Expose pre/post plane commit steps separately. We need to expose the actual hw commit step anyway for drivers to be able to implement asynchronous commit workers. But if we expose pre/post and plane commit steps individually we allow drivers to selectively use atomic helpers. - I've forgotten to call encoder/bridge ->mode_set functions, fix this. v4: Add debug output and fix a mixup between current and new state that resulted in crtcs not getting updated correctly. And in an Oops ... v5: - Be kind to driver writers in the vblank wait functions.. if thing aren't working yet, and vblank irq will never come, then let's not block forever.. especially under console-lock. - Correctly clear connector_state->best_encoder when disabling. Spotted while trying to understand a report from Rob Clark. - Only steal encoder if it actually changed, otherwise hilarity ensues if we steal from the current connector and so set the ->crtc pointer unexpectedly to NULL. Reported by Rob Clark. - Bail out in disable_outputs if an output currently doesn't have a best_encoder - this means it's already disabled. v6: Fixupe kerneldoc as reported by Paulo. And also fix up kerneldoc in drm_crtc.h. v7: Take ownership of the atomic state and clean it up with drm_atomic_state_free(). v8 Various improvements all over: - Polish code comments and kerneldoc. - Improve debug output to make sure all failure cases are logged. - Treat enabled crtc with no connectors as invalid input from userspace. - Don't ignore the return value from mode_fixup(). v9: - Improve debug output for crtc_state->mode_changed. v10: - Fixup the vblank waiting code to properly balance the vblank_get/put calls. - Better comments when checking/computing crtc->mode_changed v11: Fixup the encoder stealing logic: We can't look at encoder->crtc since that's not in the atomic state structures and might be updated asynchronously in and async commit. Instead we need to inspect all the connector states and check whether the encoder is currently in used and if so, on which crtc. v12: Review from Sean: - A few spelling fixes. - Flatten control flow indent by converting if blocks to early continue/return in 2 places. - Capture connectors_for_crtc return value in int num_connectors instead of bool has_connectors and do an explicit int->bool conversion with !!. I think the helper is more useful for drivers if it returns the number of connectors (e.g. to detect cloning configurations), so decided to keep that return value. Cc: Sean Paul <seanpaul@chromium.org> Cc: Paulo Zanoni <przanoni@gmail.com> Cc: Rob Clark <robdclark@gmail.com> Reviewed-by: Sean Paul <seanpaul@chromium.org> Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2014-09-16 15:50:47 +00:00
struct drm_atomic_state *old_state);
drm: Add atomic/plane helpers This is the first cut of atomic helper code. As-is it's only useful to implement a pure atomic interface for plane updates. Later patches will integrate this with the crtc helpers so that full atomic updates are possible. We also need a pile of helpers to aid drivers in transitioning from the legacy world to the shiny new atomic age. Finally we need helpers to implement legacy ioctls on top of the atomic interface. The design of the overall helpers<->driver interaction is fairly simple, but has an unfortunate large interface: - We have ->atomic_check callbacks for crtcs and planes. The idea is that connectors don't need any checking, and if they do they can adjust the relevant crtc driver-private state. So no connector hooks should be needed. Also the crtc helpers integration will do the ->best_encoder checks, so no need for that. - Framebuffer pinning needs to be done before we can commit to the hw state. This is especially important for async updates where we must pin all buffers before returning to userspace, so that really only hw failures can happen in the asynchronous worker. Hence we add ->prepare_fb and ->cleanup_fb hooks for this resources management. - The actual atomic plane commit can't fail (except hw woes), so has void return type. It has three stages: 1. Prepare all affected crtcs with crtc->atomic_begin. Drivers can use this to unset the GO bit or similar latches to prevent plane updates. 2. Update plane state by looping over all changed planes and calling plane->atomic_update. Presuming the hardware is sane and has GO bits drivers can simply bash the state into the hardware in this function. Other drivers might use this to precompute hw state for the final step. 3. Finally latch the update for the next vblank with crtc->atomic_flush. Note that this function doesn't need to wait for the vblank to happen even for the synchronous case. v2: Clear drm_<obj>_state->state to NULL when swapping in state. v3: Add TODO that we don't short-circuit plane updates for now. Likely no one will care. v4: Squash in a bit of polish that somehow landed in the wrong (later) patche. v5: Integrate atomic functions into the drm docbook and fixup the kerneldoc. v6: Fixup fixup patch squashing fumble. v7: Don't touch the legacy plane state plane->fb and plane->crtc. This is only used by the legacy ioctl code in the drm core, and that code already takes care of updating the pointers in all relevant cases. This is in stark contrast to connector->encoder->crtc links on the modeset side, which we still need to set since the core doesn't touch them. Also some more kerneldoc polish. v8: Drop outdated comment. v9: Handle the state->state pointer correctly: Only clearing the ->state pointer when assigning the state to the kms object isn't good enough. We also need to re-link the swapped out state into the drm_atomic_state structure. v10: Shuffle the misplaced docbook template hunk around that Sean spotted. Cc: Sean Paul <seanpaul@chromium.org> Reviewed-by: Sean Paul <seanpaul@chromium.org> Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2014-11-04 23:14:14 +00:00
int drm_atomic_helper_prepare_planes(struct drm_device *dev,
struct drm_atomic_state *state);
#define DRM_PLANE_COMMIT_ACTIVE_ONLY BIT(0)
#define DRM_PLANE_COMMIT_NO_DISABLE_AFTER_MODESET BIT(1)
drm: Add atomic/plane helpers This is the first cut of atomic helper code. As-is it's only useful to implement a pure atomic interface for plane updates. Later patches will integrate this with the crtc helpers so that full atomic updates are possible. We also need a pile of helpers to aid drivers in transitioning from the legacy world to the shiny new atomic age. Finally we need helpers to implement legacy ioctls on top of the atomic interface. The design of the overall helpers<->driver interaction is fairly simple, but has an unfortunate large interface: - We have ->atomic_check callbacks for crtcs and planes. The idea is that connectors don't need any checking, and if they do they can adjust the relevant crtc driver-private state. So no connector hooks should be needed. Also the crtc helpers integration will do the ->best_encoder checks, so no need for that. - Framebuffer pinning needs to be done before we can commit to the hw state. This is especially important for async updates where we must pin all buffers before returning to userspace, so that really only hw failures can happen in the asynchronous worker. Hence we add ->prepare_fb and ->cleanup_fb hooks for this resources management. - The actual atomic plane commit can't fail (except hw woes), so has void return type. It has three stages: 1. Prepare all affected crtcs with crtc->atomic_begin. Drivers can use this to unset the GO bit or similar latches to prevent plane updates. 2. Update plane state by looping over all changed planes and calling plane->atomic_update. Presuming the hardware is sane and has GO bits drivers can simply bash the state into the hardware in this function. Other drivers might use this to precompute hw state for the final step. 3. Finally latch the update for the next vblank with crtc->atomic_flush. Note that this function doesn't need to wait for the vblank to happen even for the synchronous case. v2: Clear drm_<obj>_state->state to NULL when swapping in state. v3: Add TODO that we don't short-circuit plane updates for now. Likely no one will care. v4: Squash in a bit of polish that somehow landed in the wrong (later) patche. v5: Integrate atomic functions into the drm docbook and fixup the kerneldoc. v6: Fixup fixup patch squashing fumble. v7: Don't touch the legacy plane state plane->fb and plane->crtc. This is only used by the legacy ioctl code in the drm core, and that code already takes care of updating the pointers in all relevant cases. This is in stark contrast to connector->encoder->crtc links on the modeset side, which we still need to set since the core doesn't touch them. Also some more kerneldoc polish. v8: Drop outdated comment. v9: Handle the state->state pointer correctly: Only clearing the ->state pointer when assigning the state to the kms object isn't good enough. We also need to re-link the swapped out state into the drm_atomic_state structure. v10: Shuffle the misplaced docbook template hunk around that Sean spotted. Cc: Sean Paul <seanpaul@chromium.org> Reviewed-by: Sean Paul <seanpaul@chromium.org> Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2014-11-04 23:14:14 +00:00
void drm_atomic_helper_commit_planes(struct drm_device *dev,
2015-09-08 10:02:07 +00:00
struct drm_atomic_state *state,
uint32_t flags);
drm: Add atomic/plane helpers This is the first cut of atomic helper code. As-is it's only useful to implement a pure atomic interface for plane updates. Later patches will integrate this with the crtc helpers so that full atomic updates are possible. We also need a pile of helpers to aid drivers in transitioning from the legacy world to the shiny new atomic age. Finally we need helpers to implement legacy ioctls on top of the atomic interface. The design of the overall helpers<->driver interaction is fairly simple, but has an unfortunate large interface: - We have ->atomic_check callbacks for crtcs and planes. The idea is that connectors don't need any checking, and if they do they can adjust the relevant crtc driver-private state. So no connector hooks should be needed. Also the crtc helpers integration will do the ->best_encoder checks, so no need for that. - Framebuffer pinning needs to be done before we can commit to the hw state. This is especially important for async updates where we must pin all buffers before returning to userspace, so that really only hw failures can happen in the asynchronous worker. Hence we add ->prepare_fb and ->cleanup_fb hooks for this resources management. - The actual atomic plane commit can't fail (except hw woes), so has void return type. It has three stages: 1. Prepare all affected crtcs with crtc->atomic_begin. Drivers can use this to unset the GO bit or similar latches to prevent plane updates. 2. Update plane state by looping over all changed planes and calling plane->atomic_update. Presuming the hardware is sane and has GO bits drivers can simply bash the state into the hardware in this function. Other drivers might use this to precompute hw state for the final step. 3. Finally latch the update for the next vblank with crtc->atomic_flush. Note that this function doesn't need to wait for the vblank to happen even for the synchronous case. v2: Clear drm_<obj>_state->state to NULL when swapping in state. v3: Add TODO that we don't short-circuit plane updates for now. Likely no one will care. v4: Squash in a bit of polish that somehow landed in the wrong (later) patche. v5: Integrate atomic functions into the drm docbook and fixup the kerneldoc. v6: Fixup fixup patch squashing fumble. v7: Don't touch the legacy plane state plane->fb and plane->crtc. This is only used by the legacy ioctl code in the drm core, and that code already takes care of updating the pointers in all relevant cases. This is in stark contrast to connector->encoder->crtc links on the modeset side, which we still need to set since the core doesn't touch them. Also some more kerneldoc polish. v8: Drop outdated comment. v9: Handle the state->state pointer correctly: Only clearing the ->state pointer when assigning the state to the kms object isn't good enough. We also need to re-link the swapped out state into the drm_atomic_state structure. v10: Shuffle the misplaced docbook template hunk around that Sean spotted. Cc: Sean Paul <seanpaul@chromium.org> Reviewed-by: Sean Paul <seanpaul@chromium.org> Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2014-11-04 23:14:14 +00:00
void drm_atomic_helper_cleanup_planes(struct drm_device *dev,
struct drm_atomic_state *old_state);
void drm_atomic_helper_commit_planes_on_crtc(struct drm_crtc_state *old_crtc_state);
void
drm_atomic_helper_disable_planes_on_crtc(struct drm_crtc_state *old_crtc_state,
bool atomic);
drm: Add atomic/plane helpers This is the first cut of atomic helper code. As-is it's only useful to implement a pure atomic interface for plane updates. Later patches will integrate this with the crtc helpers so that full atomic updates are possible. We also need a pile of helpers to aid drivers in transitioning from the legacy world to the shiny new atomic age. Finally we need helpers to implement legacy ioctls on top of the atomic interface. The design of the overall helpers<->driver interaction is fairly simple, but has an unfortunate large interface: - We have ->atomic_check callbacks for crtcs and planes. The idea is that connectors don't need any checking, and if they do they can adjust the relevant crtc driver-private state. So no connector hooks should be needed. Also the crtc helpers integration will do the ->best_encoder checks, so no need for that. - Framebuffer pinning needs to be done before we can commit to the hw state. This is especially important for async updates where we must pin all buffers before returning to userspace, so that really only hw failures can happen in the asynchronous worker. Hence we add ->prepare_fb and ->cleanup_fb hooks for this resources management. - The actual atomic plane commit can't fail (except hw woes), so has void return type. It has three stages: 1. Prepare all affected crtcs with crtc->atomic_begin. Drivers can use this to unset the GO bit or similar latches to prevent plane updates. 2. Update plane state by looping over all changed planes and calling plane->atomic_update. Presuming the hardware is sane and has GO bits drivers can simply bash the state into the hardware in this function. Other drivers might use this to precompute hw state for the final step. 3. Finally latch the update for the next vblank with crtc->atomic_flush. Note that this function doesn't need to wait for the vblank to happen even for the synchronous case. v2: Clear drm_<obj>_state->state to NULL when swapping in state. v3: Add TODO that we don't short-circuit plane updates for now. Likely no one will care. v4: Squash in a bit of polish that somehow landed in the wrong (later) patche. v5: Integrate atomic functions into the drm docbook and fixup the kerneldoc. v6: Fixup fixup patch squashing fumble. v7: Don't touch the legacy plane state plane->fb and plane->crtc. This is only used by the legacy ioctl code in the drm core, and that code already takes care of updating the pointers in all relevant cases. This is in stark contrast to connector->encoder->crtc links on the modeset side, which we still need to set since the core doesn't touch them. Also some more kerneldoc polish. v8: Drop outdated comment. v9: Handle the state->state pointer correctly: Only clearing the ->state pointer when assigning the state to the kms object isn't good enough. We also need to re-link the swapped out state into the drm_atomic_state structure. v10: Shuffle the misplaced docbook template hunk around that Sean spotted. Cc: Sean Paul <seanpaul@chromium.org> Reviewed-by: Sean Paul <seanpaul@chromium.org> Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2014-11-04 23:14:14 +00:00
int __must_check drm_atomic_helper_swap_state(struct drm_atomic_state *state,
bool stall);
drm: Add atomic/plane helpers This is the first cut of atomic helper code. As-is it's only useful to implement a pure atomic interface for plane updates. Later patches will integrate this with the crtc helpers so that full atomic updates are possible. We also need a pile of helpers to aid drivers in transitioning from the legacy world to the shiny new atomic age. Finally we need helpers to implement legacy ioctls on top of the atomic interface. The design of the overall helpers<->driver interaction is fairly simple, but has an unfortunate large interface: - We have ->atomic_check callbacks for crtcs and planes. The idea is that connectors don't need any checking, and if they do they can adjust the relevant crtc driver-private state. So no connector hooks should be needed. Also the crtc helpers integration will do the ->best_encoder checks, so no need for that. - Framebuffer pinning needs to be done before we can commit to the hw state. This is especially important for async updates where we must pin all buffers before returning to userspace, so that really only hw failures can happen in the asynchronous worker. Hence we add ->prepare_fb and ->cleanup_fb hooks for this resources management. - The actual atomic plane commit can't fail (except hw woes), so has void return type. It has three stages: 1. Prepare all affected crtcs with crtc->atomic_begin. Drivers can use this to unset the GO bit or similar latches to prevent plane updates. 2. Update plane state by looping over all changed planes and calling plane->atomic_update. Presuming the hardware is sane and has GO bits drivers can simply bash the state into the hardware in this function. Other drivers might use this to precompute hw state for the final step. 3. Finally latch the update for the next vblank with crtc->atomic_flush. Note that this function doesn't need to wait for the vblank to happen even for the synchronous case. v2: Clear drm_<obj>_state->state to NULL when swapping in state. v3: Add TODO that we don't short-circuit plane updates for now. Likely no one will care. v4: Squash in a bit of polish that somehow landed in the wrong (later) patche. v5: Integrate atomic functions into the drm docbook and fixup the kerneldoc. v6: Fixup fixup patch squashing fumble. v7: Don't touch the legacy plane state plane->fb and plane->crtc. This is only used by the legacy ioctl code in the drm core, and that code already takes care of updating the pointers in all relevant cases. This is in stark contrast to connector->encoder->crtc links on the modeset side, which we still need to set since the core doesn't touch them. Also some more kerneldoc polish. v8: Drop outdated comment. v9: Handle the state->state pointer correctly: Only clearing the ->state pointer when assigning the state to the kms object isn't good enough. We also need to re-link the swapped out state into the drm_atomic_state structure. v10: Shuffle the misplaced docbook template hunk around that Sean spotted. Cc: Sean Paul <seanpaul@chromium.org> Reviewed-by: Sean Paul <seanpaul@chromium.org> Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2014-11-04 23:14:14 +00:00
/* nonblocking commit helpers */
int drm_atomic_helper_setup_commit(struct drm_atomic_state *state,
bool nonblock);
void drm_atomic_helper_wait_for_dependencies(struct drm_atomic_state *state);
void drm_atomic_helper_commit_hw_done(struct drm_atomic_state *state);
void drm_atomic_helper_commit_cleanup_done(struct drm_atomic_state *state);
drm/atomic-helper: implementatations for legacy interfaces Well, except page_flip since that requires async commit, which isn't there yet. For the functions which changes planes there's a bit of trickery involved to keep the fb refcounting working. But otherwise fairly straight-forward atomic updates. The property setting functions are still a bit incomplete. Once we have generic properties (e.g. rotation, but also all the properties needed by the atomic ioctl) we need to filter those out and parse them in the helper. Preferrably with the same function as used by the real atomic ioctl implementation. v2: Fixup kerneldoc, reported by Paulo. v3: Add missing EXPORT_SYMBOL. v4: We need to look at the crtc of the modeset, not some random leftover one from a previous loop when udpating the connector->crtc routing. Also push some local variables into inner loops to avoid these kinds of bugs. v5: Adjust semantics - drivers now own the atomic state upon successfully synchronous commit. v6: Use the set_crtc_for_plane function to assign the crtc, since otherwise the book-keeping is off. v7: - Improve comments. - Filter out the crtc of the ->set_config call when recomputing crtc_state->enabled: We should compute the same state, but not doing so will give us a good chance to catch bugs and inconsistencies - the atomic helper's atomic_check function re-validates this again. - Fix the set_config implementation logic when disabling the crtc: We still need to update the output routing to disable all the connectors properly in the state. Caught by the atomic_check functions, so at least that part worked ;-) Also add some WARN_ONs to ensure ->set_config preconditions all apply. v8: Fixup an embarrassing h/vdisplay mixup. v9: Shuffled bad squash to the right patch, spotted by Daniel v10: Use set_crtc_for_connector as suggested by Sean. v11: Daniel Thompson noticed that my error handling is inconsistent and that in a few cases I didn't handle fatal errors (i.e. not -EDEADLK). Fix this by consolidate the ww mutex backoff handling into one check in the fail: block and flatten the error control flow everywhere else. v12: Review and discussion with Sean: - One spelling fix. - Correctly skip the crtc from the set_config set when recomputing ->enable state. That should allow us to catch any bugs in higher levels in computing that state (which is supplied to the ->set_config implementation). I've screwed this up and Sean spotted that the current code is pointless. Cc: Sean Paul <seanpaul@chromium.org> Cc: Daniel Thompson <daniel.thompson@linaro.org> Cc: Sean Paul <seanpaul@chromium.org> Cc: Daniel Thompson <daniel.thompson@linaro.org> Cc: Paulo Zanoni <przanoni@gmail.com> Reviewed-by: Sean Paul <seanpaul@chromium.org> Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2014-07-27 11:46:52 +00:00
/* implementations for legacy interfaces */
int drm_atomic_helper_update_plane(struct drm_plane *plane,
struct drm_crtc *crtc,
struct drm_framebuffer *fb,
int crtc_x, int crtc_y,
unsigned int crtc_w, unsigned int crtc_h,
uint32_t src_x, uint32_t src_y,
uint32_t src_w, uint32_t src_h,
struct drm_modeset_acquire_ctx *ctx);
int drm_atomic_helper_disable_plane(struct drm_plane *plane,
struct drm_modeset_acquire_ctx *ctx);
int __drm_atomic_helper_disable_plane(struct drm_plane *plane,
struct drm_plane_state *plane_state);
int drm_atomic_helper_set_config(struct drm_mode_set *set,
struct drm_modeset_acquire_ctx *ctx);
int __drm_atomic_helper_set_config(struct drm_mode_set *set,
struct drm_atomic_state *state);
drm/atomic-helper: implementatations for legacy interfaces Well, except page_flip since that requires async commit, which isn't there yet. For the functions which changes planes there's a bit of trickery involved to keep the fb refcounting working. But otherwise fairly straight-forward atomic updates. The property setting functions are still a bit incomplete. Once we have generic properties (e.g. rotation, but also all the properties needed by the atomic ioctl) we need to filter those out and parse them in the helper. Preferrably with the same function as used by the real atomic ioctl implementation. v2: Fixup kerneldoc, reported by Paulo. v3: Add missing EXPORT_SYMBOL. v4: We need to look at the crtc of the modeset, not some random leftover one from a previous loop when udpating the connector->crtc routing. Also push some local variables into inner loops to avoid these kinds of bugs. v5: Adjust semantics - drivers now own the atomic state upon successfully synchronous commit. v6: Use the set_crtc_for_plane function to assign the crtc, since otherwise the book-keeping is off. v7: - Improve comments. - Filter out the crtc of the ->set_config call when recomputing crtc_state->enabled: We should compute the same state, but not doing so will give us a good chance to catch bugs and inconsistencies - the atomic helper's atomic_check function re-validates this again. - Fix the set_config implementation logic when disabling the crtc: We still need to update the output routing to disable all the connectors properly in the state. Caught by the atomic_check functions, so at least that part worked ;-) Also add some WARN_ONs to ensure ->set_config preconditions all apply. v8: Fixup an embarrassing h/vdisplay mixup. v9: Shuffled bad squash to the right patch, spotted by Daniel v10: Use set_crtc_for_connector as suggested by Sean. v11: Daniel Thompson noticed that my error handling is inconsistent and that in a few cases I didn't handle fatal errors (i.e. not -EDEADLK). Fix this by consolidate the ww mutex backoff handling into one check in the fail: block and flatten the error control flow everywhere else. v12: Review and discussion with Sean: - One spelling fix. - Correctly skip the crtc from the set_config set when recomputing ->enable state. That should allow us to catch any bugs in higher levels in computing that state (which is supplied to the ->set_config implementation). I've screwed this up and Sean spotted that the current code is pointless. Cc: Sean Paul <seanpaul@chromium.org> Cc: Daniel Thompson <daniel.thompson@linaro.org> Cc: Sean Paul <seanpaul@chromium.org> Cc: Daniel Thompson <daniel.thompson@linaro.org> Cc: Paulo Zanoni <przanoni@gmail.com> Reviewed-by: Sean Paul <seanpaul@chromium.org> Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2014-07-27 11:46:52 +00:00
int drm_atomic_helper_disable_all(struct drm_device *dev,
struct drm_modeset_acquire_ctx *ctx);
void drm_atomic_helper_shutdown(struct drm_device *dev);
struct drm_atomic_state *drm_atomic_helper_suspend(struct drm_device *dev);
int drm_atomic_helper_commit_duplicated_state(struct drm_atomic_state *state,
struct drm_modeset_acquire_ctx *ctx);
int drm_atomic_helper_resume(struct drm_device *dev,
struct drm_atomic_state *state);
drm/atomic-helper: implement ->page_flip Currently there is no way to implement async flips using atomic, that essentially requires us to be able to cancel pending requests mid-flight. To be able to do that (and I guess we want this since vblank synced updates which opportunistically cancel still pending updates seem to be wanted) we'd need to add a mandatory cancellation mode. Depending upon the exact semantics we decide upon that could mean that userspace will not get completion events, or will get them all stacked up. So reject async updates for now. Also async updates usually means not vblank synced at all, and I guess for drivers which want to support this they should simply add a special pageflip handler (since usually you need a special flip cmd to achieve this). That kind of async flip is pretty much exclusively just used for games and benchmarks where dropping just one frame means you'll get a headshot or something bad like that ... And so slight amounts of tearing is acceptable. v2: Fixup kerneldoc, reported by Paulo. v3: Use the set_crtc_for_plane function to assign the crtc, since otherwise the book-keeping is off. v4: Update crtc->primary->fb since ->page_flip is the only driver callback where the core won't do this itself. We might want to fix this inconsistency eventually. v5: Use set_crtc_for_connector as suggested by Sean. v6: Daniel Thompson noticed that my error handling is inconsistent and that in a few cases I didn't handle fatal errors (i.e. not -EDEADLK). Fix this by consolidate the ww mutex backoff handling into one check in the fail: block and flatten the error control flow everywhere else. v7: Fix spelling mistake in the commit message (Sean). Cc: Daniel Thompson <daniel.thompson@linaro.org> Cc: Sean Paul <seanpaul@chromium.org> Cc: Paulo Zanoni <przanoni@gmail.com> Reviewed-by: Sean Paul <seanpaul@chromium.org> Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2014-07-27 16:42:37 +00:00
int drm_atomic_helper_page_flip(struct drm_crtc *crtc,
struct drm_framebuffer *fb,
struct drm_pending_vblank_event *event,
uint32_t flags,
struct drm_modeset_acquire_ctx *ctx);
int drm_atomic_helper_page_flip_target(
struct drm_crtc *crtc,
struct drm_framebuffer *fb,
struct drm_pending_vblank_event *event,
uint32_t flags,
uint32_t target,
struct drm_modeset_acquire_ctx *ctx);
struct drm_encoder *
drm_atomic_helper_best_encoder(struct drm_connector *connector);
drm/atomic-helper: implement ->page_flip Currently there is no way to implement async flips using atomic, that essentially requires us to be able to cancel pending requests mid-flight. To be able to do that (and I guess we want this since vblank synced updates which opportunistically cancel still pending updates seem to be wanted) we'd need to add a mandatory cancellation mode. Depending upon the exact semantics we decide upon that could mean that userspace will not get completion events, or will get them all stacked up. So reject async updates for now. Also async updates usually means not vblank synced at all, and I guess for drivers which want to support this they should simply add a special pageflip handler (since usually you need a special flip cmd to achieve this). That kind of async flip is pretty much exclusively just used for games and benchmarks where dropping just one frame means you'll get a headshot or something bad like that ... And so slight amounts of tearing is acceptable. v2: Fixup kerneldoc, reported by Paulo. v3: Use the set_crtc_for_plane function to assign the crtc, since otherwise the book-keeping is off. v4: Update crtc->primary->fb since ->page_flip is the only driver callback where the core won't do this itself. We might want to fix this inconsistency eventually. v5: Use set_crtc_for_connector as suggested by Sean. v6: Daniel Thompson noticed that my error handling is inconsistent and that in a few cases I didn't handle fatal errors (i.e. not -EDEADLK). Fix this by consolidate the ww mutex backoff handling into one check in the fail: block and flatten the error control flow everywhere else. v7: Fix spelling mistake in the commit message (Sean). Cc: Daniel Thompson <daniel.thompson@linaro.org> Cc: Sean Paul <seanpaul@chromium.org> Cc: Paulo Zanoni <przanoni@gmail.com> Reviewed-by: Sean Paul <seanpaul@chromium.org> Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2014-07-27 16:42:37 +00:00
/* default implementations for state handling */
void drm_atomic_helper_crtc_reset(struct drm_crtc *crtc);
void __drm_atomic_helper_crtc_duplicate_state(struct drm_crtc *crtc,
struct drm_crtc_state *state);
struct drm_crtc_state *
drm_atomic_helper_crtc_duplicate_state(struct drm_crtc *crtc);
void __drm_atomic_helper_crtc_destroy_state(struct drm_crtc_state *state);
void drm_atomic_helper_crtc_destroy_state(struct drm_crtc *crtc,
struct drm_crtc_state *state);
void drm_atomic_helper_plane_reset(struct drm_plane *plane);
void __drm_atomic_helper_plane_duplicate_state(struct drm_plane *plane,
struct drm_plane_state *state);
struct drm_plane_state *
drm_atomic_helper_plane_duplicate_state(struct drm_plane *plane);
void __drm_atomic_helper_plane_destroy_state(struct drm_plane_state *state);
void drm_atomic_helper_plane_destroy_state(struct drm_plane *plane,
struct drm_plane_state *state);
void __drm_atomic_helper_connector_reset(struct drm_connector *connector,
struct drm_connector_state *conn_state);
void drm_atomic_helper_connector_reset(struct drm_connector *connector);
void
__drm_atomic_helper_connector_duplicate_state(struct drm_connector *connector,
struct drm_connector_state *state);
struct drm_connector_state *
drm_atomic_helper_connector_duplicate_state(struct drm_connector *connector);
struct drm_atomic_state *
drm_atomic_helper_duplicate_state(struct drm_device *dev,
struct drm_modeset_acquire_ctx *ctx);
void
__drm_atomic_helper_connector_destroy_state(struct drm_connector_state *state);
void drm_atomic_helper_connector_destroy_state(struct drm_connector *connector,
struct drm_connector_state *state);
int drm_atomic_helper_legacy_gamma_set(struct drm_crtc *crtc,
u16 *red, u16 *green, u16 *blue,
uint32_t size,
struct drm_modeset_acquire_ctx *ctx);
void __drm_atomic_helper_private_obj_duplicate_state(struct drm_private_obj *obj,
struct drm_private_state *state);
/**
* drm_atomic_crtc_for_each_plane - iterate over planes currently attached to CRTC
* @plane: the loop cursor
* @crtc: the crtc whose planes are iterated
*
* This iterates over the current state, useful (for example) when applying
* atomic state after it has been checked and swapped. To iterate over the
* planes which *will* be attached (more useful in code called from
* &drm_mode_config_funcs.atomic_check) see
* drm_atomic_crtc_state_for_each_plane().
*/
#define drm_atomic_crtc_for_each_plane(plane, crtc) \
drm_for_each_plane_mask(plane, (crtc)->dev, (crtc)->state->plane_mask)
/**
* drm_crtc_atomic_state_for_each_plane - iterate over attached planes in new state
* @plane: the loop cursor
* @crtc_state: the incoming crtc-state
*
* Similar to drm_crtc_for_each_plane(), but iterates the planes that will be
* attached if the specified state is applied. Useful during for example
* in code called from &drm_mode_config_funcs.atomic_check operations, to
* validate the incoming state.
*/
#define drm_atomic_crtc_state_for_each_plane(plane, crtc_state) \
drm_for_each_plane_mask(plane, (crtc_state)->state->dev, (crtc_state)->plane_mask)
drm/atomic-helper: implementatations for legacy interfaces Well, except page_flip since that requires async commit, which isn't there yet. For the functions which changes planes there's a bit of trickery involved to keep the fb refcounting working. But otherwise fairly straight-forward atomic updates. The property setting functions are still a bit incomplete. Once we have generic properties (e.g. rotation, but also all the properties needed by the atomic ioctl) we need to filter those out and parse them in the helper. Preferrably with the same function as used by the real atomic ioctl implementation. v2: Fixup kerneldoc, reported by Paulo. v3: Add missing EXPORT_SYMBOL. v4: We need to look at the crtc of the modeset, not some random leftover one from a previous loop when udpating the connector->crtc routing. Also push some local variables into inner loops to avoid these kinds of bugs. v5: Adjust semantics - drivers now own the atomic state upon successfully synchronous commit. v6: Use the set_crtc_for_plane function to assign the crtc, since otherwise the book-keeping is off. v7: - Improve comments. - Filter out the crtc of the ->set_config call when recomputing crtc_state->enabled: We should compute the same state, but not doing so will give us a good chance to catch bugs and inconsistencies - the atomic helper's atomic_check function re-validates this again. - Fix the set_config implementation logic when disabling the crtc: We still need to update the output routing to disable all the connectors properly in the state. Caught by the atomic_check functions, so at least that part worked ;-) Also add some WARN_ONs to ensure ->set_config preconditions all apply. v8: Fixup an embarrassing h/vdisplay mixup. v9: Shuffled bad squash to the right patch, spotted by Daniel v10: Use set_crtc_for_connector as suggested by Sean. v11: Daniel Thompson noticed that my error handling is inconsistent and that in a few cases I didn't handle fatal errors (i.e. not -EDEADLK). Fix this by consolidate the ww mutex backoff handling into one check in the fail: block and flatten the error control flow everywhere else. v12: Review and discussion with Sean: - One spelling fix. - Correctly skip the crtc from the set_config set when recomputing ->enable state. That should allow us to catch any bugs in higher levels in computing that state (which is supplied to the ->set_config implementation). I've screwed this up and Sean spotted that the current code is pointless. Cc: Sean Paul <seanpaul@chromium.org> Cc: Daniel Thompson <daniel.thompson@linaro.org> Cc: Sean Paul <seanpaul@chromium.org> Cc: Daniel Thompson <daniel.thompson@linaro.org> Cc: Paulo Zanoni <przanoni@gmail.com> Reviewed-by: Sean Paul <seanpaul@chromium.org> Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2014-07-27 11:46:52 +00:00
/**
* drm_crtc_atomic_state_for_each_plane_state - iterate over attached planes in new state
* @plane: the loop cursor
* @plane_state: loop cursor for the plane's state, must be const
* @crtc_state: the incoming crtc-state
*
* Similar to drm_crtc_for_each_plane(), but iterates the planes that will be
* attached if the specified state is applied. Useful during for example
* in code called from &drm_mode_config_funcs.atomic_check operations, to
* validate the incoming state.
*
* Compared to just drm_atomic_crtc_state_for_each_plane() this also fills in a
* const plane_state. This is useful when a driver just wants to peek at other
* active planes on this crtc, but does not need to change it.
*/
#define drm_atomic_crtc_state_for_each_plane_state(plane, plane_state, crtc_state) \
drm_for_each_plane_mask(plane, (crtc_state)->state->dev, (crtc_state)->plane_mask) \
for_each_if ((plane_state = \
__drm_atomic_get_current_plane_state((crtc_state)->state, \
plane)))
/**
drm/plane: Add optional ->atomic_disable() callback In order to prevent drivers from having to perform the same checks over and over again, add an optional ->atomic_disable callback which the core calls under the right circumstances. v2: pass old state and detect edges to avoid calling ->atomic_disable on already disabled planes, remove redundant comment (Daniel Vetter) v3: rename helper to drm_atomic_plane_disabling() to clarify that it is checking for transitions, move helper to drm_atomic_helper.h, clarify check for !old_state and its relation to transitional helpers Here's an extract from some discussion rationalizing the behaviour (for a full version, see the reference below): > > Hm, thinking about this some more this will result in a slight difference > > in behaviour, at least when drivers just use the helper ->reset functions > > but don't disable everything: > > - With transitional helpers we assume we know nothing and call > > ->atomic_disable. > > - With atomic old_state->crtc == NULL in the same situation right after > > boot-up, but we asssume the plane is really off and _dont_ call > > ->atomic_disable. > > > > Should we instead check for (old_state && old_state->crtc) and state that > > drivers need to make sure they don't have stuff hanging around? > > I don't think we can check for old_state because otherwise this will > always return false, whereas we really want it to force-disable planes > that could be on (lacking any more accurate information). For > transitional helpers anyway. > > For the atomic helpers, old_state will never be NULL, but I'd assume > that the driver would reconstruct the current state in ->reset(). By the way, the reason for why old_state can be NULL with transitional helpers is the ordering of the steps in the atomic transition. Currently the Tegra patches do this (based on your blog post and the Exynos proto- type): 1) atomic conversion, phase 1: - implement ->atomic_{check,update,disable}() - use drm_plane_helper_{update,disable}() 2) atomic conversion, phase 2: - call drm_mode_config_reset() from ->load() - implement ->reset() That's only a partial list of what's done in these steps, but that's the only relevant pieces for why old_state is NULL. What happens is that without ->reset() implemented there won't be any initial state, hence plane->state (the old_state here) will be NULL the first time atomic state is applied. We could of course reorder the sequence such that drivers are required to hook up ->reset() before they can (or at the same as they) hook up the transitional helpers. We could add an appropriate WARN_ON to this helper to make that more obvious. However, that will not solve the problem because it only gets rid of the special case. We still don't know whether old_state->crtc == NULL is the current state or just the initial default. So no matter which way we do this, I don't see a way to get away without requiring specific semantics from drivers. They would be that: - drivers recreate the correct state in ->reset() so that old_state->crtc != NULL if the plane is really enabled or - drivers have to ensure that the real state in fact mirrors the initial default as encoded in the state (plane disabled) References: http://lists.freedesktop.org/archives/dri-devel/2015-January/075578.html Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch> Reviewed-by: Gustavo Padovan <gustavo.padovan@collabora.co.uk> Signed-off-by: Thierry Reding <treding@nvidia.com>
2014-11-20 11:05:50 +00:00
* drm_atomic_plane_disabling - check whether a plane is being disabled
* @old_plane_state: old atomic plane state
* @new_plane_state: new atomic plane state
drm/plane: Add optional ->atomic_disable() callback In order to prevent drivers from having to perform the same checks over and over again, add an optional ->atomic_disable callback which the core calls under the right circumstances. v2: pass old state and detect edges to avoid calling ->atomic_disable on already disabled planes, remove redundant comment (Daniel Vetter) v3: rename helper to drm_atomic_plane_disabling() to clarify that it is checking for transitions, move helper to drm_atomic_helper.h, clarify check for !old_state and its relation to transitional helpers Here's an extract from some discussion rationalizing the behaviour (for a full version, see the reference below): > > Hm, thinking about this some more this will result in a slight difference > > in behaviour, at least when drivers just use the helper ->reset functions > > but don't disable everything: > > - With transitional helpers we assume we know nothing and call > > ->atomic_disable. > > - With atomic old_state->crtc == NULL in the same situation right after > > boot-up, but we asssume the plane is really off and _dont_ call > > ->atomic_disable. > > > > Should we instead check for (old_state && old_state->crtc) and state that > > drivers need to make sure they don't have stuff hanging around? > > I don't think we can check for old_state because otherwise this will > always return false, whereas we really want it to force-disable planes > that could be on (lacking any more accurate information). For > transitional helpers anyway. > > For the atomic helpers, old_state will never be NULL, but I'd assume > that the driver would reconstruct the current state in ->reset(). By the way, the reason for why old_state can be NULL with transitional helpers is the ordering of the steps in the atomic transition. Currently the Tegra patches do this (based on your blog post and the Exynos proto- type): 1) atomic conversion, phase 1: - implement ->atomic_{check,update,disable}() - use drm_plane_helper_{update,disable}() 2) atomic conversion, phase 2: - call drm_mode_config_reset() from ->load() - implement ->reset() That's only a partial list of what's done in these steps, but that's the only relevant pieces for why old_state is NULL. What happens is that without ->reset() implemented there won't be any initial state, hence plane->state (the old_state here) will be NULL the first time atomic state is applied. We could of course reorder the sequence such that drivers are required to hook up ->reset() before they can (or at the same as they) hook up the transitional helpers. We could add an appropriate WARN_ON to this helper to make that more obvious. However, that will not solve the problem because it only gets rid of the special case. We still don't know whether old_state->crtc == NULL is the current state or just the initial default. So no matter which way we do this, I don't see a way to get away without requiring specific semantics from drivers. They would be that: - drivers recreate the correct state in ->reset() so that old_state->crtc != NULL if the plane is really enabled or - drivers have to ensure that the real state in fact mirrors the initial default as encoded in the state (plane disabled) References: http://lists.freedesktop.org/archives/dri-devel/2015-January/075578.html Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch> Reviewed-by: Gustavo Padovan <gustavo.padovan@collabora.co.uk> Signed-off-by: Thierry Reding <treding@nvidia.com>
2014-11-20 11:05:50 +00:00
*
* Checks the atomic state of a plane to determine whether it's being disabled
* or not. This also WARNs if it detects an invalid state (both CRTC and FB
* need to either both be NULL or both be non-NULL).
*
* RETURNS:
* True if the plane is being disabled, false otherwise.
*/
static inline bool
drm_atomic_plane_disabling(struct drm_plane_state *old_plane_state,
struct drm_plane_state *new_plane_state)
drm/plane: Add optional ->atomic_disable() callback In order to prevent drivers from having to perform the same checks over and over again, add an optional ->atomic_disable callback which the core calls under the right circumstances. v2: pass old state and detect edges to avoid calling ->atomic_disable on already disabled planes, remove redundant comment (Daniel Vetter) v3: rename helper to drm_atomic_plane_disabling() to clarify that it is checking for transitions, move helper to drm_atomic_helper.h, clarify check for !old_state and its relation to transitional helpers Here's an extract from some discussion rationalizing the behaviour (for a full version, see the reference below): > > Hm, thinking about this some more this will result in a slight difference > > in behaviour, at least when drivers just use the helper ->reset functions > > but don't disable everything: > > - With transitional helpers we assume we know nothing and call > > ->atomic_disable. > > - With atomic old_state->crtc == NULL in the same situation right after > > boot-up, but we asssume the plane is really off and _dont_ call > > ->atomic_disable. > > > > Should we instead check for (old_state && old_state->crtc) and state that > > drivers need to make sure they don't have stuff hanging around? > > I don't think we can check for old_state because otherwise this will > always return false, whereas we really want it to force-disable planes > that could be on (lacking any more accurate information). For > transitional helpers anyway. > > For the atomic helpers, old_state will never be NULL, but I'd assume > that the driver would reconstruct the current state in ->reset(). By the way, the reason for why old_state can be NULL with transitional helpers is the ordering of the steps in the atomic transition. Currently the Tegra patches do this (based on your blog post and the Exynos proto- type): 1) atomic conversion, phase 1: - implement ->atomic_{check,update,disable}() - use drm_plane_helper_{update,disable}() 2) atomic conversion, phase 2: - call drm_mode_config_reset() from ->load() - implement ->reset() That's only a partial list of what's done in these steps, but that's the only relevant pieces for why old_state is NULL. What happens is that without ->reset() implemented there won't be any initial state, hence plane->state (the old_state here) will be NULL the first time atomic state is applied. We could of course reorder the sequence such that drivers are required to hook up ->reset() before they can (or at the same as they) hook up the transitional helpers. We could add an appropriate WARN_ON to this helper to make that more obvious. However, that will not solve the problem because it only gets rid of the special case. We still don't know whether old_state->crtc == NULL is the current state or just the initial default. So no matter which way we do this, I don't see a way to get away without requiring specific semantics from drivers. They would be that: - drivers recreate the correct state in ->reset() so that old_state->crtc != NULL if the plane is really enabled or - drivers have to ensure that the real state in fact mirrors the initial default as encoded in the state (plane disabled) References: http://lists.freedesktop.org/archives/dri-devel/2015-January/075578.html Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch> Reviewed-by: Gustavo Padovan <gustavo.padovan@collabora.co.uk> Signed-off-by: Thierry Reding <treding@nvidia.com>
2014-11-20 11:05:50 +00:00
{
/*
* When disabling a plane, CRTC and FB should always be NULL together.
* Anything else should be considered a bug in the atomic core, so we
* gently warn about it.
*/
WARN_ON((new_plane_state->crtc == NULL && new_plane_state->fb != NULL) ||
(new_plane_state->crtc != NULL && new_plane_state->fb == NULL));
drm/plane: Add optional ->atomic_disable() callback In order to prevent drivers from having to perform the same checks over and over again, add an optional ->atomic_disable callback which the core calls under the right circumstances. v2: pass old state and detect edges to avoid calling ->atomic_disable on already disabled planes, remove redundant comment (Daniel Vetter) v3: rename helper to drm_atomic_plane_disabling() to clarify that it is checking for transitions, move helper to drm_atomic_helper.h, clarify check for !old_state and its relation to transitional helpers Here's an extract from some discussion rationalizing the behaviour (for a full version, see the reference below): > > Hm, thinking about this some more this will result in a slight difference > > in behaviour, at least when drivers just use the helper ->reset functions > > but don't disable everything: > > - With transitional helpers we assume we know nothing and call > > ->atomic_disable. > > - With atomic old_state->crtc == NULL in the same situation right after > > boot-up, but we asssume the plane is really off and _dont_ call > > ->atomic_disable. > > > > Should we instead check for (old_state && old_state->crtc) and state that > > drivers need to make sure they don't have stuff hanging around? > > I don't think we can check for old_state because otherwise this will > always return false, whereas we really want it to force-disable planes > that could be on (lacking any more accurate information). For > transitional helpers anyway. > > For the atomic helpers, old_state will never be NULL, but I'd assume > that the driver would reconstruct the current state in ->reset(). By the way, the reason for why old_state can be NULL with transitional helpers is the ordering of the steps in the atomic transition. Currently the Tegra patches do this (based on your blog post and the Exynos proto- type): 1) atomic conversion, phase 1: - implement ->atomic_{check,update,disable}() - use drm_plane_helper_{update,disable}() 2) atomic conversion, phase 2: - call drm_mode_config_reset() from ->load() - implement ->reset() That's only a partial list of what's done in these steps, but that's the only relevant pieces for why old_state is NULL. What happens is that without ->reset() implemented there won't be any initial state, hence plane->state (the old_state here) will be NULL the first time atomic state is applied. We could of course reorder the sequence such that drivers are required to hook up ->reset() before they can (or at the same as they) hook up the transitional helpers. We could add an appropriate WARN_ON to this helper to make that more obvious. However, that will not solve the problem because it only gets rid of the special case. We still don't know whether old_state->crtc == NULL is the current state or just the initial default. So no matter which way we do this, I don't see a way to get away without requiring specific semantics from drivers. They would be that: - drivers recreate the correct state in ->reset() so that old_state->crtc != NULL if the plane is really enabled or - drivers have to ensure that the real state in fact mirrors the initial default as encoded in the state (plane disabled) References: http://lists.freedesktop.org/archives/dri-devel/2015-January/075578.html Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch> Reviewed-by: Gustavo Padovan <gustavo.padovan@collabora.co.uk> Signed-off-by: Thierry Reding <treding@nvidia.com>
2014-11-20 11:05:50 +00:00
return old_plane_state->crtc && !new_plane_state->crtc;
drm/plane: Add optional ->atomic_disable() callback In order to prevent drivers from having to perform the same checks over and over again, add an optional ->atomic_disable callback which the core calls under the right circumstances. v2: pass old state and detect edges to avoid calling ->atomic_disable on already disabled planes, remove redundant comment (Daniel Vetter) v3: rename helper to drm_atomic_plane_disabling() to clarify that it is checking for transitions, move helper to drm_atomic_helper.h, clarify check for !old_state and its relation to transitional helpers Here's an extract from some discussion rationalizing the behaviour (for a full version, see the reference below): > > Hm, thinking about this some more this will result in a slight difference > > in behaviour, at least when drivers just use the helper ->reset functions > > but don't disable everything: > > - With transitional helpers we assume we know nothing and call > > ->atomic_disable. > > - With atomic old_state->crtc == NULL in the same situation right after > > boot-up, but we asssume the plane is really off and _dont_ call > > ->atomic_disable. > > > > Should we instead check for (old_state && old_state->crtc) and state that > > drivers need to make sure they don't have stuff hanging around? > > I don't think we can check for old_state because otherwise this will > always return false, whereas we really want it to force-disable planes > that could be on (lacking any more accurate information). For > transitional helpers anyway. > > For the atomic helpers, old_state will never be NULL, but I'd assume > that the driver would reconstruct the current state in ->reset(). By the way, the reason for why old_state can be NULL with transitional helpers is the ordering of the steps in the atomic transition. Currently the Tegra patches do this (based on your blog post and the Exynos proto- type): 1) atomic conversion, phase 1: - implement ->atomic_{check,update,disable}() - use drm_plane_helper_{update,disable}() 2) atomic conversion, phase 2: - call drm_mode_config_reset() from ->load() - implement ->reset() That's only a partial list of what's done in these steps, but that's the only relevant pieces for why old_state is NULL. What happens is that without ->reset() implemented there won't be any initial state, hence plane->state (the old_state here) will be NULL the first time atomic state is applied. We could of course reorder the sequence such that drivers are required to hook up ->reset() before they can (or at the same as they) hook up the transitional helpers. We could add an appropriate WARN_ON to this helper to make that more obvious. However, that will not solve the problem because it only gets rid of the special case. We still don't know whether old_state->crtc == NULL is the current state or just the initial default. So no matter which way we do this, I don't see a way to get away without requiring specific semantics from drivers. They would be that: - drivers recreate the correct state in ->reset() so that old_state->crtc != NULL if the plane is really enabled or - drivers have to ensure that the real state in fact mirrors the initial default as encoded in the state (plane disabled) References: http://lists.freedesktop.org/archives/dri-devel/2015-January/075578.html Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch> Reviewed-by: Gustavo Padovan <gustavo.padovan@collabora.co.uk> Signed-off-by: Thierry Reding <treding@nvidia.com>
2014-11-20 11:05:50 +00:00
}
drm: Add atomic/plane helpers This is the first cut of atomic helper code. As-is it's only useful to implement a pure atomic interface for plane updates. Later patches will integrate this with the crtc helpers so that full atomic updates are possible. We also need a pile of helpers to aid drivers in transitioning from the legacy world to the shiny new atomic age. Finally we need helpers to implement legacy ioctls on top of the atomic interface. The design of the overall helpers<->driver interaction is fairly simple, but has an unfortunate large interface: - We have ->atomic_check callbacks for crtcs and planes. The idea is that connectors don't need any checking, and if they do they can adjust the relevant crtc driver-private state. So no connector hooks should be needed. Also the crtc helpers integration will do the ->best_encoder checks, so no need for that. - Framebuffer pinning needs to be done before we can commit to the hw state. This is especially important for async updates where we must pin all buffers before returning to userspace, so that really only hw failures can happen in the asynchronous worker. Hence we add ->prepare_fb and ->cleanup_fb hooks for this resources management. - The actual atomic plane commit can't fail (except hw woes), so has void return type. It has three stages: 1. Prepare all affected crtcs with crtc->atomic_begin. Drivers can use this to unset the GO bit or similar latches to prevent plane updates. 2. Update plane state by looping over all changed planes and calling plane->atomic_update. Presuming the hardware is sane and has GO bits drivers can simply bash the state into the hardware in this function. Other drivers might use this to precompute hw state for the final step. 3. Finally latch the update for the next vblank with crtc->atomic_flush. Note that this function doesn't need to wait for the vblank to happen even for the synchronous case. v2: Clear drm_<obj>_state->state to NULL when swapping in state. v3: Add TODO that we don't short-circuit plane updates for now. Likely no one will care. v4: Squash in a bit of polish that somehow landed in the wrong (later) patche. v5: Integrate atomic functions into the drm docbook and fixup the kerneldoc. v6: Fixup fixup patch squashing fumble. v7: Don't touch the legacy plane state plane->fb and plane->crtc. This is only used by the legacy ioctl code in the drm core, and that code already takes care of updating the pointers in all relevant cases. This is in stark contrast to connector->encoder->crtc links on the modeset side, which we still need to set since the core doesn't touch them. Also some more kerneldoc polish. v8: Drop outdated comment. v9: Handle the state->state pointer correctly: Only clearing the ->state pointer when assigning the state to the kms object isn't good enough. We also need to re-link the swapped out state into the drm_atomic_state structure. v10: Shuffle the misplaced docbook template hunk around that Sean spotted. Cc: Sean Paul <seanpaul@chromium.org> Reviewed-by: Sean Paul <seanpaul@chromium.org> Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2014-11-04 23:14:14 +00:00
#endif /* DRM_ATOMIC_HELPER_H_ */