Commit Graph

22 Commits

Author SHA1 Message Date
Daniel Vetter 1931529448 drm: Add acquire ctx parameter to ->plane_disable
Nouveau had a few direct calls to ->disable_plane, I replaced those
with drm_plane_force_disable. Same story for shmob.

Otherwise no code changes.

Cc: Ben Skeggs <bskeggs@redhat.com>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Reviewed-by: Harry Wentland <harry.wentland@amd.com>
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20170322215058.8671-5-daniel.vetter@ffwll.ch
2017-03-29 09:14:58 +02:00
Daniel Vetter 34a2ab5e06 drm: Add acquire ctx parameter to ->update_plane
Just rolling it out, no code change here.

Cc: Ben Skeggs <bskeggs@redhat.com>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Rob Clark <robdclark@gmail.com>
Cc: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Cc: Eric Anholt <eric@anholt.net>
Reviewed-by: Harry Wentland <harry.wentland@amd.com>
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20170322215058.8671-3-daniel.vetter@ffwll.ch
2017-03-29 09:14:01 +02:00
Daniel Vetter 1de72faf10 drm/kms-helpers: Extract drm_modeset_helper.[hc]
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
2016-08-16 16:10:19 +02:00
Ville Syrjälä df86af9133 drm/plane-helper: Add drm_plane_helper_check_state()
Add a version of drm_plane_helper_check_update() which takes a plane
state instead of having the caller pass in everything.

And to reduce code duplication, let's reimplement
drm_plane_helper_check_update() in terms of the new function, by
having a tempororary plane state on the stack.

v2: Add a note that the functions modifies the state (Chris)
v3: Fix drm_plane_helper_check_update() y coordinates (Daniel Kurtz)

Cc: Daniel Kurtz <djkurtz@chromium.org>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: Sean Paul <seanpaul@chromium.org> (v2)
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: Sean Paul <seanpaul@chromium.org>
Link: http://patchwork.freedesktop.org/patch/msgid/1470642910-14073-1-git-send-email-ville.syrjala@linux.intel.com
2016-08-08 14:19:45 -04:00
Ville Syrjälä 9b8b013dde drm: Deal with rotation in drm_plane_helper_check_update()
drm_plane_helper_check_update() needs to account for the plane rotation
for correct clipping/scaling calculations. Do so.

There was an earlier attempt [1] to add this into
intel_check_primary_plane() but I requested that it'd be put into the
helper instead. An updated patch never materialized AFAICS, so I went
ahead and cooked one up myself.

v2: Deal with new drm_plane_helper_check_update() callers

[1] https://patchwork.freedesktop.org/patch/65177/
Cc: Nabendu Maiti <nabendu.bikash.maiti@intel.com>
Cc: Noralf Trønnes <noralf@tronnes.org>
Cc: CK Hu <ck.hu@mediatek.com>
Cc: Mark Yao <mark.yao@rock-chips.com>
Cc: Russell King <rmk+kernel@armlinux.org.uk>
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: Patrik Jakobsson <patrik.r.jakobsson@gmail.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/1466172790-10025-1-git-send-email-ville.syrjala@linux.intel.com
2016-06-17 16:41:25 +02:00
Daniel Vetter 092d01dae0 drm: Reorganize helper vtables and their docs
Currently we have 4 helper libraries (probe, crtc, plane & atomic)
that all use the same helper vtables. And that's by necessity since we
don't want to litter the core structs with one ops pointer per helper
library. Also often the reuse the same hooks (like atomic does, to
facilite conversion from existing drivers using crtc and plane
helpers).

Given all that it doesn't make sense to put the docs for these next to
specific helpers. Instead extract them into a new header file and
section in the docbook, and add references to them everywhere.

Unfortunately kernel-doc complains when an include directive doesn't
find anything (and it does by dumping crap into the output file). We
have to remove the now empty includes to avoid that, instead of leaving
them in for future proofing.

v2: More OCD in ordering functions.

v3: Spelling plus collate copyright headers properly.

Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1449218769-16577-4-git-send-email-daniel.vetter@ffwll.ch
Reviewed-by: Thierry Reding <treding@nvidia.com>
2015-12-08 16:07:52 +01:00
Maarten Lankhorst 844f9111f6 drm/atomic: Make prepare_fb/cleanup_fb only take state, v3.
This removes the need to separately track fb changes i915.
That will be done as a separate commit, however.

Changes since v1:
- Add dri-devel to cc.
- Fix a check in intel's prepare and cleanup fb to take rotation
  into account.
Changes since v2:
- Split out i915 changes to a separate commit.

Cc: dri-devel@lists.freedesktop.org
Signed-off-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Reviewed-by: Daniel Stone <daniels@collabora.com>
[danvet: Squash in msm fixup from Maarten.]
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2015-09-08 13:45:54 +02:00
Thierry Reding b54a0935b0 drm/plane: Remove redundant extern
Use of the extern keyword for function prototypes is unnecessary, so it
can be removed.

Signed-off-by: Thierry Reding <treding@nvidia.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2015-08-12 17:15:12 +02:00
Jani Nikula 9a436ee6c3 drm: make crtc/encoder/connector/plane helper_private a const pointer
They're only used to store const pointers anyway. This helps to keep
Ville and the compiler happy.

Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Reviewed-by: Christian König <christian.koenig@amd.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2015-04-13 15:00:13 +02:00
Daniel Vetter 3461b30b3e drm/plane-helper: unexport drm_primary_helper_create_plane
We shouldn't tempt driver writers into using this since it uses a
default format list which is likely wrong. And when that's done we can
simplify the code a bit, too.

Noticed while reviewing a patch from Laurent.

Cc: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Cc: Matt Roper <matthew.d.roper@intel.com>
Reviewed-by: Matt Roper <matthew.d.roper@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
2015-03-10 09:59:35 +01:00
Tvrtko Ursulin d136dfeec8 drm: Pass in new and old plane state to prepare_fb and cleanup_fb
Use cases like rotation require these hooks to have some context so they
know how to prepare and cleanup the frame buffer correctly.

For i915 specifically, object backing pages need to be mapped differently
for different rotation modes and the driver needs to know which mapping to
instantiate and which to tear down when transitioning between them.

v2: Made passed in states const. (Daniel Vetter)

[airlied: add mdp5 and atmel fixups]
Signed-off-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: dri-devel@lists.freedesktop.org
Reviewed-by: Rob Clark <robdclark@gmail.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>
2015-03-05 09:49:02 +10:00
Thierry Reding 407b8bd9f5 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>
2015-01-27 10:14:42 +01:00
Thierry Reding 3cad4b6887 drm/plane: Make ->atomic_update() mandatory
There is no use-case where it would be useful for drivers not to
implement this function and the transitional plane helpers already
require drivers to provide an implementation.

v2: add new requirement to kerneldoc

Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Thierry Reding <treding@nvidia.com>
2015-01-27 10:14:41 +01:00
Thierry Reding 5d57169015 drm/plane: Add missing kerneldoc
The plane helpers aren't pulled into the DocBook yet, so these weren't
noticed.

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>
2014-11-25 13:28:04 +01:00
Thierry Reding f1c37e1adc drm/plane: Pass old state to ->atomic_update()
In most situations it will be useful to have the old state passed to the
->atomic_update() callback. For example if a plane is being disabled the
new state's .crtc field will be NULL, but some drivers may rely on this
field to program the CRTCs registers.

v2: rename variable to old_plane_state and remove redundant comment as
suggested by Daniel Vetter, remove an Exynos hunk that doesn't apply to
drm-next and add a hunk for pending MSM mdp5 changes

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>
2014-11-25 13:27:58 +01:00
Daniel Vetter 2f324b42b7 drm/crtc-helper: Transitional functions using atomic plane helpers
These two functions allow drivers to reuse their atomic plane helpers
functions for the primary plane to implement the interfaces required
by the crtc helpers for the legacy ->set_config callback.

This is purely transitional and won't be used once the driver is fully
converted. But it allows partial conversions to the atomic plane
helpers which are functional.

v2:
- Use ->atomic_duplicate_state if available.
- Don't forget to run crtc_funcs->atomic_check.

v3: Shift source coordinates correctly for 16.16 fixed point.

v4: Don't forget to call ->atomic_destroy_state if available.

v5: Fixup kerneldoc.

v6: Reuse the plane_commit function from the transitional plane
helpers to avoid too much duplication.

v7:
- Remove some stale comment.
- Correctly handle the lack of plane->state object, necessary for
  transitional use.

v8: Fixup an embarrassing h/vdisplay mixup.

Reviewed-by: Sean Paul <seanpaul@chromium.org>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2014-11-05 18:44:59 +01:00
Daniel Vetter acf24a395c drm/plane-helper: transitional atomic plane helpers
Converting a driver to the atomic interface can be a daunting
undertaking. One of the prerequisites is to have full universal planes
support.

To make that transition a bit easier this patch provides plane helpers
which use the new atomic helper callbacks just only for the plane
changes. This way the plane update functionality can be tested without
being forced to convert everything at once.

Of course a real atomic update capable driver will implement the
all plane properties through the atomic interface, so these helpers
are mostly transitional. But they can be used to enable proper
universal plane support, especially once the crtc helpers have also
been adapted.

v2: Use ->atomic_duplicate_state if available.

v3: Don't forget to call ->atomic_destroy_state if available.

v4: Fixup kerneldoc, reported by Paulo.

v5: Extract a common plane_commit helper and fix some bugs in the
plane_state setup of the plane_disable implementation.

v6: Fix issues with the cleanup of the old fb. Since transitional
helpers can be mixed we need to assume that the old fb has been set up
by a legacy path (e.g. set_config or page_flip when the primary plane
is converted to use these functions already). Hence pass an additional
old_fb parameter to plane_commit to do that cleanup work correctly.

v7:
- Fix spurious WARNING (crtc helpers really love to disable stuff
  harder) and fix array index bonghits.
- Correctly handle the lack of plane->state object, necessary for
  transitional use.
- Don't indicate failure if drm_vblank_get doesn't work - that's
  expected when the pipe is in dpms off mode.

v8: Review from Sean:
- s/fail/out/ to make the meaning of a label more clear.
- spelling fix in the commit message.

Cc: Paulo Zanoni <przanoni@gmail.com>
Cc: Sean Paul <seanpaul@chromium.org>
Reviewed-by: Sean Paul <seanpaul@chromium.org>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2014-11-05 18:07:01 +01:00
Daniel Vetter c2fcd274bc 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>
2014-11-05 18:07:01 +01:00
Daniel Vetter 3cb9ae4fd8 drm: Move drm_crtc_init from drm_crtc.h to drm_plane_helper.h
Just a bit of OCD cleanup on headers - this function isn't the core
interface any more but just a helper for drivers who haven't yet
transitioned to universal planes. Put the declaration at the right
spot and sprinkle necessary #includes over all drivers.

Maybe this helps to encourage driver maintainers to do the switch.

v2: Fix #include ordering for tegra, reported by 0-day builder.

v3: Include required headers, reported by Thierry.

Cc: Matt Roper <matthew.d.roper@intel.com>
Cc: Thierry Reding <treding@nvidia.com>
Reviewed-by: Matt Roper <matthew.d.roper@intel.com>
Reviewed-by: Sean Paul <seanpaul@chromium.org>
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
2014-11-05 00:14:55 +01:00
Matt Roper 7daf8d54c1 drm/plane-helper: Add drm_plane_helper_check_update() (v3)
Pull the parameter checking from drm_primary_helper_update() out into
its own function; drivers that provide their own setplane()
implementations rather than using the helper may still want to share
this parameter checking logic.

A few of the checks here were also updated based on suggestions by
Ville Syrjälä.

v3:
 - s/primary_helper/plane_helper/ --- this checking logic may be useful
   for other types of planes as well.
 - Fix visibility check (need to dereference visibility pointer)
v2:
 - Pass src/dest/clip rects and min/max scaling down to helper to avoid
   duplication of effort between helper and drivers (suggested by
   Ville).
 - Allow caller to specify whether the primary plane should be
   updatable while the crtc is disabled.

Cc: dri-devel@lists.freedesktop.org
Reviewed-by: Chon Ming Lee <chon.ming.lee@intel.com>
Signed-off-by: Matt Roper <matthew.d.roper@intel.com>
Acked-by: Dave Airlie <airlied@gmail.com>
[danvet: Include header properly and fixup declaration mismatch to
make this compile.]
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2014-06-05 08:52:43 +02:00
Thierry Reding f220e62659 drm/plane: Fix sparse warnings
Include the drm_plane_helper.h header file to fix the following sparse
warnings:

	  CHECK   drivers/gpu/drm/drm_plane_helper.c
	drivers/gpu/drm/drm_plane_helper.c:102:5: warning: symbol 'drm_primary_helper_update' was not declared. Should it be static?
	drivers/gpu/drm/drm_plane_helper.c:219:5: warning: symbol 'drm_primary_helper_disable' was not declared. Should it be static?
	drivers/gpu/drm/drm_plane_helper.c:233:6: warning: symbol 'drm_primary_helper_destroy' was not declared. Should it be static?
	drivers/gpu/drm/drm_plane_helper.c:241:30: warning: symbol 'drm_primary_helper_funcs' was not declared. Should it be static?
	drivers/gpu/drm/drm_plane_helper.c:259:18: warning: symbol 'drm_primary_helper_create_plane' was not declared. Should it be static?

Doing that makes gcc complain as follows:

	  CC      drivers/gpu/drm/drm_plane_helper.o
	drivers/gpu/drm/drm_plane_helper.c:260:19: error: conflicting types for 'drm_primary_helper_create_plane'
	 struct drm_plane *drm_primary_helper_create_plane(struct drm_device *dev,
	                   ^
	In file included from drivers/gpu/drm/drm_plane_helper.c:29:0:
	include/drm/drm_plane_helper.h:42:19: note: previous declaration of 'drm_primary_helper_create_plane' was here
	 struct drm_plane *drm_primary_helper_create_plane(struct drm_device *dev,
	                   ^
	drivers/gpu/drm/drm_plane_helper.c: In function 'drm_primary_helper_create_plane':
	drivers/gpu/drm/drm_plane_helper.c:274:11: warning: assignment discards 'const' qualifier from pointer target type
	   formats = safe_modeset_formats;
	           ^
	In file included from include/linux/linkage.h:6:0,
	                 from include/linux/kernel.h:6,
	                 from include/drm/drmP.h:45,
	                 from drivers/gpu/drm/drm_plane_helper.c:27:
	drivers/gpu/drm/drm_plane_helper.c: At top level:
	drivers/gpu/drm/drm_plane_helper.c:289:15: error: conflicting types for 'drm_primary_helper_create_plane'
	 EXPORT_SYMBOL(drm_primary_helper_create_plane);
	               ^
	include/linux/export.h:57:21: note: in definition of macro '__EXPORT_SYMBOL'
	  extern typeof(sym) sym;     \
	                     ^
	drivers/gpu/drm/drm_plane_helper.c:289:1: note: in expansion of macro 'EXPORT_SYMBOL'
	 EXPORT_SYMBOL(drm_primary_helper_create_plane);
	 ^
	In file included from drivers/gpu/drm/drm_plane_helper.c:29:0:
	include/drm/drm_plane_helper.h:42:19: note: previous declaration of 'drm_primary_helper_create_plane' was here
	 struct drm_plane *drm_primary_helper_create_plane(struct drm_device *dev,
	                   ^

Which can easily be fixed by making the signatures of the implementation
and the prototype match.

Signed-off-by: Thierry Reding <treding@nvidia.com>
Reviewed-by: Matt Roper <matthew.d.roper@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2014-06-02 09:57:30 +02:00
Matt Roper c103d1cfb3 drm: Add primary plane helpers (v3)
When we expose non-overlay planes to userspace, they will become
accessible via standard userspace plane API's.  We should be able to
handle the standard plane operations against primary planes in a generic
way via the modeset handler.

Drivers that can program primary planes more efficiently, that want to
use their own primary plane structure to track additional information,
or that don't have the limitations assumed by the helpers are free to
provide their own implementation of some or all of these handlers.

v3: Tweak kerneldoc formatting slightly to avoid ugliness
v2:
 - Move plane helpers to a new file (drm_plane_helper.c)
 - Tighten checks on update handler (check for scaling, CRTC coverage,
   subpixel positioning)
 - Pass proper panning parameters to modeset interface
 - Disallow disabling primary plane (and thus CRTC) if other planes are
   still active on the CRTC.
 - Use a minimal format list that should work on all hardware/drivers.
   Drivers may call this function with a more accurate plane list to
   enable additional formats they can support.

Signed-off-by: Matt Roper <matthew.d.roper@intel.com>
Reviewed-by: Rob Clark <robdclark@gmail.com>
2014-04-01 20:11:28 -04:00