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path: root/include/drm/drm_atomic_helper.h
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2016-09-12drm/fence: allow fence waiting to be interrupted by userspaceGustavo Padovan
If userspace is running an synchronously atomic commit and interrupts the atomic operation during fence_wait() it will hang until the timer expires, so here we change the wait to be interruptible so it stop immediately when userspace wants to quit. Also adds the necessary error checking for fence_wait(). v2: Comment by Daniel Vetter - Add error checking for fence_wait() v3: Rebase on top of new atomic noblocking support v4: Comment by Maarten Lankhorst - remove 'swapped' bitfield as it was duplicating information v5: Comments by Maarten Lankhorst - assign plane->state to plane_state if !intr - squash previous patch into this one v6: Comment by Sean Paul - rename intr to pre_swap Signed-off-by: Gustavo Padovan <gustavo.padovan@collabora.co.uk> Reviewed-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com> [seanpaul fixed a couple checkpatch warnings and moved the preswap comment] Signed-off-by: Sean Paul <seanpaul@chromium.org> Link: http://patchwork.freedesktop.org/patch/msgid/1473707291-14781-1-git-send-email-gustavo@padovan.org
2016-08-29drm/atomic-helper: Add NO_DISABLE_AFTER_MODESET flag support for plane commitLiu Ying
Drivers may set the NO_DISABLE_AFTER_MODESET flag in the 'flags' parameter of the helper drm_atomic_helper_commit_planes() if the relevant display controllers(e.g., IPUv3 for imx-drm) require to disable a CRTC's planes when the CRTC is disabled. The helper would skip the ->atomic_disable call for a plane if the CRTC of the old plane state needs a modesetting operation. Of course, the drivers need to disable the planes in their CRTC disable callbacks since no one else would do that. Suggested-by: Daniel Vetter <daniel.vetter@ffwll.ch> Cc: Philipp Zabel <p.zabel@pengutronix.de> Cc: David Airlie <airlied@linux.ie> Cc: Russell King <linux@armlinux.org.uk> Cc: Peter Senna Tschudin <peter.senna@gmail.com> Cc: Lucas Stach <l.stach@pengutronix.de> Signed-off-by: Liu Ying <gnuiyl@gmail.com> Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch> Link: http://patchwork.freedesktop.org/patch/msgid/1472461923-14364-1-git-send-email-gnuiyl@gmail.com
2016-08-29drm/atomic-helper: Disable appropriate planes in disable_planes_on_crtc()Liu Ying
Currently, the helper drm_atomic_helper_disable_planes_on_crtc() calls ->atomic_disable for all planes _to be_ enabled on a particular CRTC. This is obviously wrong for those planes which are not scanning out frames when the helper is called. Instead, it's sane to disable active planes of old_crtc_state in the helper. Suggested-by: Daniel Vetter <daniel.vetter@ffwll.ch> Cc: Philipp Zabel <p.zabel@pengutronix.de> Cc: David Airlie <airlied@linux.ie> Cc: Russell King <linux@armlinux.org.uk> Cc: Peter Senna Tschudin <peter.senna@gmail.com> Cc: Lucas Stach <l.stach@pengutronix.de> Signed-off-by: Liu Ying <gnuiyl@gmail.com> Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch> Link: http://patchwork.freedesktop.org/patch/msgid/1472196644-30563-3-git-send-email-gnuiyl@gmail.com
2016-08-16drm/kms-helpers: Extract drm_modeset_helper.[hc]Daniel Vetter
While reviewing docs I spotted that we have a few functions that really just don't fit into their containing helper library section. Extract them and shovel them all into a new library for random one-off aux stuff. v2: Remove wrongly added files for real. Cc: Sean Paul <seanpaul@chromium.org> Reviewed-by: Sean Paul <seanpaul@chromium.org> Signed-off-by: Daniel Vetter <daniel.vetter@intel.com> Link: http://patchwork.freedesktop.org/patch/msgid/1471034937-651-3-git-send-email-daniel.vetter@ffwll.ch
2016-06-10drm: Fix comment making reference to non-existing functionLiviu Dudau
Documentation for drm_atomic_crtc_for_each_plane() makes reference to a function called drm_crtc_for_each_pending_plane(). I've guessed that the actual function name is drm_atomic_crtc_state_for_each_plane() as that matches best the intent of the comment. Signed-off-by: Liviu Dudau <Liviu.Dudau@arm.com> Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch> Link: http://patchwork.freedesktop.org/patch/msgid/1465571005-3877-1-git-send-email-Liviu.Dudau@arm.com
2016-06-10drm/atomic-helper: nonblocking commit supportDaniel Vetter
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
2016-06-10drm/atomic-helper: roll out commit synchronizationDaniel Vetter
To facilitate easier reviewing this is split out from the overall nonblocking commit rework. It just rolls out the helper functions and uses them in the main drm_atomic_helper_commit() function to make it clear where in the flow they're used. The next patch will actually split drm_atomic_helper_commit() into 2 pieces, with the tail being run asynchronously from a worker. v2: Improve kerneldocs (Maarten). v3: Don't convert ERESTARTSYS to EINTR (Maarten). Also don't fail if the wait succeed in stall_check - we need to convert that case (it returns the remaining jiffies) to 0 for success. v4: Switch to long for wait_for_completion_timeout return value everywhere (Maarten). v5: Fix miscaped function in kerneldoc (Maarten). Reviewed-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com> 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> Signed-off-by: Daniel Vetter <daniel.vetter@intel.com> Link: http://patchwork.freedesktop.org/patch/msgid/1465398936-22305-1-git-send-email-daniel.vetter@ffwll.ch
2016-06-10drm/atomic-helper: Massage swap_state signature somewhatDaniel Vetter
- dev is redundant, we have state->atomic - add stall parameter, which must be set when swapping needs to stall for preceeding commits to stop looking at ->state pointers. Currently all drivers need this to be, just prep work for a glorious future. v2: Rebased on top of commit e7cf0963f816fa44190caaf51aeffaa614c340c6 Author: Gerd Hoffmann <kraxel@redhat.com> Date: Tue May 31 08:50:47 2016 +0200 virtio-gpu: add atomic_commit function Cc: Gerd Hoffmann <kraxel@redhat.com> Reviewed-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com> Cc: Maarten Lankhorst <maarten.lankhorst@linux.intel.com> Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch> Link: http://patchwork.freedesktop.org/patch/msgid/1465509992-19284-1-git-send-email-daniel.vetter@ffwll.ch Link: http://patchwork.freedesktop.org/patch/msgid/1465388359-8070-2-git-send-email-daniel.vetter@ffwll.ch
2016-06-07drm/core: Change declaration for gamma_set.Maarten Lankhorst
Change return value to int to propagate errors from gamma_set, and remove start parameter. Updates always use the full size, and some drivers even ignore the start parameter altogether. This is needed for atomic drivers, where an atomic commit can fail with -EINTR or -ENOMEM and should be restarted. This is already and issue for drm_atomic_helper_legacy_set_gamma, which this patch fixes up. Changes since v1: - Fix compiler warning. (Emil) - Fix commit message (Daniel) Cc: Alex Deucher <alexander.deucher@amd.com> Acked-by: Alex Deucher <alexander.deucher@amd.com> Cc: Christian König <christian.koenig@amd.com> Cc: David Airlie <airlied@linux.ie> Cc: Patrik Jakobsson <patrik.r.jakobsson@gmail.com> Cc: Ben Skeggs <bskeggs@redhat.com> Cc: Eric Anholt <eric@anholt.net> Cc: VMware Graphics <linux-graphics-maintainer@vmware.com> Cc: Mathieu Larouche <mathieu.larouche@matrox.com> Cc: Thierry Reding <treding@nvidia.com> Acked-by: Patrik Jakobsson <patrik.r.jakobsson@gmail.com> Signed-off-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com> [danvet: Improve commit message a bit more, mention that this fixes the helper.] Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch> Link: http://patchwork.freedesktop.org/patch/msgid/742944bc-9f41-1acb-df4f-0fd4c8a10168@linux.intel.com
2016-06-02drm/atomic: Add drm_atomic_crtc_state_for_each_plane_stateDaniel Vetter
... and use it in msm&vc4. Again just want to encapsulate drm_atomic_state internals a bit. The const threading is a bit awkward in vc4 since C sucks, but I still think it's worth to enforce this. Eventually I want to make all the obj->state pointers const too, but that's a lot more work ... v2: Provide safe macro to wrap up the unsafe helper better, suggested by Maarten. v3: Fixup subject (Maarten) and spelling fixes (Eric Engestrom). Cc: Eric Anholt <eric@anholt.net> Cc: Rob Clark <robdclark@gmail.com> Cc: Maarten Lankhorst <maarten.lankhorst@linux.intel.com> Cc: Eric Engestrom <eric.engestrom@imgtec.com> Reviewed-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com> Signed-off-by: Daniel Vetter <daniel.vetter@intel.com> Link: http://patchwork.freedesktop.org/patch/msgid/1464877304-4213-1-git-send-email-daniel.vetter@ffwll.ch
2016-05-17drm: Drop connector argument from __drm_atomic_helper_connector_destroy_stateDaniel Vetter
It's unused, and really this helper should only look at the state structure and nothing else. Note that this conflicts with a patch from Dave that adds refcounting to drm_connectors. It's not yet clear whether the check Dave adds for connector != NULL is really needed or the right check. v2: Fix commmit message (Laurent). Cc: Dave Airlie <airlied@gmail.com> Acked-by: Thierry Reding <thierry.reding@gmail.com> Acked-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com> Acked-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> Signed-off-by: Daniel Vetter <daniel.vetter@intel.com> Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch> Link: http://patchwork.freedesktop.org/patch/msgid/1462804451-15318-3-git-send-email-daniel.vetter@ffwll.ch
2016-05-17drm: Drop plane argument from __drm_atomic_helper_plane_destroy_stateDaniel Vetter
It's unused, and really this helper should only look at the state structure and nothing else. v2: Fix commit message (Laurent). v3: Rebase onto mtk driver merge. Cc: Maarten Lankhorst <maarten.lankhorst@linux.intel.com> Cc: Thierry Reding <thierry.reding@gmail.com> Cc: Eric Anholt <eric@anholt.net> Cc: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com> Cc: Inki Dae <inki.dae@samsung.com> Cc: Tomi Valkeinen <tomi.valkeinen@ti.com> Cc: Mark Yao <mark.yao@rock-chips.com> Acked-by: Thierry Reding <thierry.reding@gmail.com> Acked-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com> Acked-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> Acked-by: Eric Anholt <eric@anholt.net> Signed-off-by: Daniel Vetter <daniel.vetter@intel.com> Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch> Link: http://patchwork.freedesktop.org/patch/msgid/1462804451-15318-2-git-send-email-daniel.vetter@ffwll.ch
2016-05-17drm: Drop crtc argument from __drm_atomic_helper_crtc_destroy_stateDaniel Vetter
It's unused, and really this helper should only look at the state structure and nothing else. v2: Rebase on top of rockchip changes v3: Drop unrelated hunk, spotted by Laurent. v4: Rebase onto mtk driver merge. Cc: Maarten Lankhorst <maarten.lankhorst@linux.intel.com> Cc: Thierry Reding <thierry.reding@gmail.com> Cc: Eric Anholt <eric@anholt.net> Cc: Mark Yao <mark.yao@rock-chips.com> Acked-by: Thierry Reding <thierry.reding@gmail.com> Acked-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com> Acked-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> Acked-by: Eric Anholt <eric@anholt.net> Signed-off-by: Daniel Vetter <daniel.vetter@intel.com> Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch> Link: http://patchwork.freedesktop.org/patch/msgid/1462804451-15318-1-git-send-email-daniel.vetter@ffwll.ch
2016-05-11drm/atomic: Add drm_atomic_helper_best_encoder()Noralf Trønnes
Add (struct drm_connector_helper_funcs *)->best_encoder callback helper for connectors that support exactly 1 encoder, statically determined at driver init time. Signed-off-by: Noralf Trønnes <noralf@tronnes.org> Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch> Link: http://patchwork.freedesktop.org/patch/msgid/1462982962-10530-6-git-send-email-noralf@tronnes.org
2016-05-02drm/atomic: Rename async parameter to nonblocking.Maarten Lankhorst
This is the first step of renaming async commit to nonblocking commit. The flag passed by userspace is NONBLOCKING, and async has a different meaning for page flips, where it means as soon as possible. Fixing up comments in drm core is done manually, to make sure I didn't miss anything. For drivers, the following cocci script is used to rename bool async to bool nonblock: @@ identifier I =~ "^async"; identifier func; @@ func(..., bool - I + nonblock , ...) { <... - I + nonblock ...> } @@ identifier func; type T; identifier I =~ "^async"; @@ T func(..., bool - I + nonblock , ...); Thanks to Tvrtko Ursulin for the cocci script. Cc: Tvrtko Ursulin <tvrtko.ursulin@linux.intel.com> Signed-off-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com> Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch> Link: http://patchwork.freedesktop.org/patch/msgid/1461679905-30177-2-git-send-email-maarten.lankhorst@linux.intel.com
2016-03-31drm/atomic: export drm_atomic_helper_wait_for_fences()Rob Clark
Signed-off-by: Rob Clark <robdclark@gmail.com> Reviewed-by: Gustavo Padovan <gustavo.padovan@collabora.co.uk> Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch> Link: http://patchwork.freedesktop.org/patch/msgid/1458342904-23326-3-git-send-email-robdclark@gmail.com
2016-03-08drm: introduce pipe color correction propertiesLionel Landwerlin
Patch based on a previous series by Shashank Sharma. This introduces optional properties to enable color correction at the pipe level. It relies on 3 transformations applied to every pixels displayed. First a lookup into a degamma table, then a multiplication of the rgb components by a 3x3 matrix and finally another lookup into a gamma table. The following properties can be added to a pipe : - DEGAMMA_LUT : blob containing degamma LUT - DEGAMMA_LUT_SIZE : number of elements in DEGAMMA_LUT - CTM : transformation matrix applied after the degamma LUT - GAMMA_LUT : blob containing gamma LUT - GAMMA_LUT_SIZE : number of elements in GAMMA_LUT DEGAMMA_LUT_SIZE and GAMMA_LUT_SIZE are read only properties, set by the driver to tell userspace applications what sizes should be the lookup tables in DEGAMMA_LUT and GAMMA_LUT. A helper is also provided so legacy gamma correction is redirected through these new properties. v2: Register LUT size properties as range v3: Fix round in drm_color_lut_get_value() helper More docs on how degamma/gamma properties are used v4: Update contributors v5: Rename CTM_MATRIX property to CTM (Doh!) Add legacy gamma_set atomic helper Describe CTM/LUT acronyms in the kernel doc v6: Fix missing blob unref in drm_atomic_helper_crtc_reset Signed-off-by: Shashank Sharma <shashank.sharma@intel.com> Signed-off-by: Kumar, Kiran S <kiran.s.kumar@intel.com> Signed-off-by: Kausal Malladi <kausalmalladi@gmail.com> Signed-off-by: Lionel Landwerlin <lionel.g.landwerlin@intel.com> Reviewed-by: Matt Roper <matthew.d.roper@intel.com> Acked-by: Rob Bradford <robert.bradford@intel.com> [danvet: CrOS maintainers are also happy with the userspacde side: https://codereview.chromium.org/1182063002/ ] Reviewed-by: Daniel Stone <daniels@collabora.com> Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch> Link: http://patchwork.freedesktop.org/patch/msgid/1456506302-640-4-git-send-email-lionel.g.landwerlin@intel.com
2016-01-20drm/atomic-helper: Export framebuffer_changed()John Keeping
The Rockchip driver cannot use drm_atomic_helper_wait_for_vblanks() because it has hardware counters for neither vblanks nor scanlines. In order to simplify re-implementing the functionality for this driver, export the framebuffer_changed() helper so it can be reused. Signed-off-by: John Keeping <john@metanate.com> Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2016-01-05drm/atomic: Add __drm_atomic_helper_connector_reset, v2.Maarten Lankhorst
This is useful for drivers that subclass connector_state, like tegra. Changes since v1: - Docbook updates. Signed-off-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com> Link: http://patchwork.freedesktop.org/patch/msgid/1451908400-25147-2-git-send-email-maarten.lankhorst@linux.intel.com Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2015-12-02drm/atomic-helper: Implement subsystem-level suspend/resumeThierry Reding
Provide subsystem-level suspend and resume helpers that can be used to implement suspend/resume on atomic mode-setting enabled drivers. v2: simplify locking, enhance kerneldoc comments v3: pass lock acquisition context by parameter, improve kerneldoc v4: - remove redundant code (already provided by atomic helpers) (Maarten Lankhorst) - move backoff dance from drm_modeset_lock_all_ctx() into suspend helper (Daniel Vetter) v5: handle potential EDEADLK from drm_atomic_helper_duplicate_state() and drm_atomic_helper_disable_all() (Daniel Vetter) Signed-off-by: Thierry Reding <treding@nvidia.com> Link: http://patchwork.freedesktop.org/patch/msgid/1449075005-13937-2-git-send-email-thierry.reding@gmail.com Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2015-11-30drm/atomic_helper: Add drm_atomic_helper_disable_planes_on_crtc()Jyri Sarha
Add drm_atomic_helper_disable_planes_on_crtc() for disabling all planes associated with the given CRTC. This can be used for instance in the CRTC helper disable callback to disable all planes before shutting down the display pipeline. v2: - Address Daniels review comments [1] - Do atomic_begin() and atomic_flush() always if they are defined and atomic knob is set - update kerneldoc - Put drm_atomic_helper_disable_planes_on_crtc() after drm_atomic_helper_commit_planes_on_crtc() in drm_atomic_helper.c to have functions in the same order as in drm_atomic_helper.h Signed-off-by: Jyri Sarha <jsarha@ti.com> Link: http://patchwork.freedesktop.org/patch/msgid/1448633641-6486-1-git-send-email-jsarha@ti.com Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2015-09-16drm/fb-helper: atomic restore_fbdev_mode()..Rob Clark
Add support for using atomic code-paths for restore_fbdev_mode(). Signed-off-by: Rob Clark <robdclark@gmail.com> [danvet: Bikeshed comments slightly.] Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2015-09-08drm/atomic-helper: Implement drm_atomic_helper_duplicate_state()Thierry Reding
This function can be used to duplicate an atomic state object. This is useful for example to implement suspend/resume, where the state before suspend can be saved and restored upon resume. v2: move locking to caller, be more explicit about prerequisites v3: explicitly pass lock acquisition context, improve kerneldoc Signed-off-by: Thierry Reding <treding@nvidia.com> Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2015-09-08drm/atomic-helper: Add option to update planes only on active crtcDaniel Vetter
With drivers supporting runtime pm it's generally not a good idea to touch the hardware when it's off. Add an option to the commit_planes helper to support this case. Note that the helpers already add all planes on a crtc when a modeset happens, hence plane updates will not be lost if drivers set this to true. v2: Check for NULL state->crtc before chasing the pointer. Also check both old and new crtc if there's a switch. Finally just outright disallow switching crtcs for a plane if the plane is in active use, on most hardware that doesn't make sense. v3: Since commit_planes(active_only = true) is for enabling things only after all the crtc are on we should only look at the new crtc to decide whether to call the plane hooks - if the current CRTC isn't on then skip. If the old crtc (when moving a plane) went down then the plane should have been disabled as part of the pipe shutdown work already. For which there's currently no helper really unfortunately. Also move the check for wether a plane gets a new CRTC assigned while still in active use out of this patch. v4: Rebase over exynos changes. Cc: Maarten Lankhorst <maarten.lankhorst@linux.intel.com> Cc: Thierry Reding <treding@nvidia.com> Cc: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com> Reviewed-by: Thierry Reding <treding@nvidia.com> Tested-by: Thierry Reding <treding@nvidia.com> Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
2015-07-27drm: Make the connector dpms callback return a value, v2.Maarten Lankhorst
This is required to properly handle failing dpms calls. When making a wait in i915 interruptible, I've noticed that the dpms sequence could fail with -ERESTARTSYS because it was waiting interruptibly for flips. So from now on allow drivers to fail in their connector dpms callback. Encoder and crtc dpms callbacks are unaffected. Changes since v1: - Update kerneldoc for the drm helper functions. Signed-off-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com> [danvet: Resolve conflicts due to different merge order.] Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2015-05-21drm/atomic: add commit_planes_on_crtc helperMaarten Lankhorst
drm_atomic_helper_commit_planes calls all atomic_begin's first, then updates all planes, finally calling atomic_flush. Some drivers may want to things like disabling irq's from their atomic_begin, in which case a second call to atomic_begin will splat. By using commit_planes_on_crtc on each crtc in the atomic state they'll evade that issue. Signed-off-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com> [danvet: Extend kerneldoc a bit as discussed with Maarten on irc.] [danvet: Squash in fixup to check for crtc_funcs in all places. Reported by Dan Carpenter.] Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2015-05-13drm/atomic-helpers: Export drm_atomic_helper_update_legacy_modeset_stateDaniel Vetter
This is useful for drivers which have their own modeset infrastructure but want to reuse most of the legacy state frobbery from the helpers. i915 wants this. v2: Add header declaration. Cc: Maarten Lankhorst <maarten.lankhorst@linux.intel.com> Reviewed-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com> Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
2015-04-08Merge tag 'drm/tegra/for-4.1-rc1' of ↵Dave Airlie
git://anongit.freedesktop.org/tegra/linux into drm-next drm/tegra: Changes for v4.1-rc1 Perhaps the most noteworthy change in this set is the implementation of a hardware VBLANK counter using host1x syncpoints. The SOR registers can now be dumped via debugfs, which can be useful while debugging. The IOVA address space maintained by the driver can also be dumped via debugfs. Other than than, these changes are mostly cleanup work, such as making register names more consistent or removing unused code (that was left over after the atomic mode-setting conversion). There's also a fix for eDP that makes the driver cope with firmware that already initialized the display (such as the firmware on the Tegra-based Chromebooks). * tag 'drm/tegra/for-4.1-rc1' of git://anongit.freedesktop.org/tegra/linux: drm/tegra: sor: Reset during initialization drm/tegra: gem: Return 64-bit offset for mmap(2) drm/tegra: hdmi: Name register fields consistently drm/tegra: hdmi: Resets are synchronous drm/tegra: dc: Document tegra_dc_state_setup_clock() drm/tegra: dc: Remove unused callbacks drm/tegra: dc: Remove unused function drm/tegra: dc: Use base atomic state helpers drm/atomic: Add helpers for state-subclassing drivers drm/tegra: dc: Implement hardware VBLANK counter gpu: host1x: Export host1x_syncpt_read() drm/tegra: sor: Dump registers via debugfs drm/tegra: sor: Registers are 32-bit drm/tegra: Provide debugfs file for the IOVA space drm/tegra: dc: Check for valid parent clock
2015-04-02drm/atomic: Add helpers for state-subclassing driversThierry Reding
Drivers that subclass CRTC, plane or connector state need to carefully duplicate the code that the atomic helpers have. This is bound to cause breakage eventually because it requires auditing all drivers and update them when code is added to the helpers. In order to avoid that, implement new helpers that perform the required steps when copying and destroying state. These new helpers are exported so that state-subclassing drivers can use them. The default helpers are implemented using them as well, providing a single location that needs to be changed when adding to base atomic states. Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch> Reviewed-by: Eric Anholt <eric@anholt.net> Signed-off-by: Thierry Reding <treding@nvidia.com>
2015-02-24drm/atomic-helper: Rename commmit_post/pre_planesDaniel Vetter
These names only make sense because of backwards compatability with the order used by the crtc helper library. There's not really any real requirement in the ordering here. So rename them to something more descriptive and update the kerneldoc a bit. Motivated in a discussion with Laurent about how to restore plane state for dpms for drivers with runtime pm. v2: Squash in fixup from Stephen Rothwell to fix a conflict with tegra. Cc: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com> Reviewed-by: Rob Clark <robdclark@gmail.com> Acked-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com> Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
2015-01-28Merge tag 'topic/atomic-core-2015-01-27' of ↵Dave Airlie
git://anongit.freedesktop.org/drm-intel into drm-next * tag 'topic/atomic-core-2015-01-27' of git://anongit.freedesktop.org/drm-intel: drm/atomic: Fix potential use of state after free drm/atomic-helper: debug output for modesets drm/atomic-helpers: Saner encoder/crtc callbacks drm/atomic-helpers: Recover full cursor plane behaviour drm/atomic-helper: add connector->dpms() implementation drm/atomic: Add drm_crtc_state->active drm: Add standardized boolean props drm/plane-helper: Fix transitional helper kerneldocs drm/plane-helper: Skip prepare_fb/cleanup_fb when newfb==oldfb Conflicts: include/drm/drm_crtc_helper.h
2015-01-27drm/plane: Add optional ->atomic_disable() callbackThierry Reding
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>
2015-01-27drm/atomic-helper: add connector->dpms() implementationDaniel Vetter
This builds on top of the crtc->active infrastructure to implement legacy DPMS. My choice of semantics is somewhat arbitrary, but the entire pipe is enabled as along as one output is still enabled. Of course it also clamps everything that's not ON to OFF. v2: Fix spelling in one comment. v3: Don't do an async commit (Thierry) v4: Dan Carpenter noticed missing error case handling. Cc: Thierry Reding <thierry.reding@gmail.com> Reviewed-by: Thierry Reding <treding@nvidia.com> Tested-by: Thierry Reding <treding@nvidia.com> Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
2014-12-17drm/atomic-helper: Export both plane and modeset check helpersDaniel Vetter
The default call sequence for these two parts won't fit for all drivers. So export the two pieces and explain with a bit of kerneldoc when each should be called. v2: Squash in fixup from Rob to actually add the newly exported functions to headers Cc: Rob Clark <robdclark@gmail.com> Reviewed-by: Rob Clark <robdclark@gmail.com> Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
2014-11-27drm/atomic: add plane iterator macrosRob Clark
Add helper macros to iterate the current, or incoming set of planes attached to a crtc. These helpers are only available for drivers converted to use atomic-helpers. Signed-off-by: Rob Clark <robdclark@gmail.com> [danvet: Squash in fixup from Rob to move the planemask iterator to drm_crtc.h and document it. That one is needed by the atomic ioctl so can't be in a helper library.] Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2014-11-25drm: Make drm_atomic_helper.h standalone includibleThierry Reding
This header uses a bunch of declarations from the drm/drm_crtc.h header, so make sure to include that as well so that drm_atomic_helper.h can be included standalone. Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch> Signed-off-by: Thierry Reding <treding@nvidia.com> Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2014-11-12drm: export atomic wait_for_vblanks helper (v2)Rob Clark
v1: original v2: danvet's kerneldoc nitpicks Signed-off-by: Rob Clark <robdclark@gmail.com> Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch> Signed-off-by: Dave Airlie <airlied@redhat.com>
2014-11-06drm/atomic-helpers: functions for state duplicate/destroy/resetDaniel Vetter
The atomic users and helpers assume that there is always a obj->state structure around. Which means drivers need to somehow create that at driver load time. Also it should obviously reset hardware state, so needs to be reset upon resume. Finally the destroy/duplicate_state functions are an awful lot of boilerplate if the driver doesn't need anything beyond the default state objects. So add helper functions for all of this. v2: Somehow the plane/connector versions got lost in the first version. v3: Add kerneldoc. v4: Make duplicate_state functions a bit more robust, which is useful for debugging state tracking issues when transitioning to atomic. v5: Clear temporary variables in the crtc state when duplicating it, like ->mode_changed or ->planes_changed. If we don't do this stale values for these might pollute the next atomic modeset. v6: Also clear crtc_state->event in case the driver didn't (yet) clear this out. v7: Split out wrong squashed commit. Also improve the kerneldoc to mention that obj->state can be NULL and when. Both suggested by Daniel Thompson. Cc: Daniel Thompson <daniel.thompson@linaro.org> Cc: Sean Paul <seanpaul@chromium.org> Reviewed-by: Sean Paul <seanpaul@chromium.org> Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2014-11-06drm/atomic-helper: implement ->page_flipDaniel Vetter
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>
2014-11-06drm/atomic-helper: implementatations for legacy interfacesDaniel Vetter
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>
2014-11-06drm: Atomic crtc/connector updates using crtc/plane helper interfacesDaniel Vetter
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>
2014-11-05drm: Add atomic/plane helpersDaniel Vetter
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>