version 6:
rebased patch on top rcar-du changes for zpos

version 4:
fix null pointer issue while setting zpos in plane reset function

This patch replaces zpos property handling custom code in rcar DRM
driver with calls to generic DRM code.
Signed-off-by: NBenjamin Gaignard <benjamin.gaignard@linaro.org>
Reviewed-by: NLaurent Pinchart <laurent.pinchart@ideasonboard.com>
Tested-by: NLaurent Pinchart <laurent.pinchart@ideasonboard.com>

Cc: Daniel Vetter <daniel@ffwll.ch>
Cc: Ville Syrjala <ville.syrjala@linux.intel.com>
Cc: Marek Szyprowski <m.szyprowski@samsung.com>

- 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 e7cf0963
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: NMaarten Lankhorst <maarten.lankhorst@linux.intel.com>
Cc: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Signed-off-by: NDaniel 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

We want to hide drm_atomic_state internals better.

v2: Use drm_crtc_mask (Maarten).

Cc: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Reviewed-by: NMaarten Lankhorst <maarten.lankhorst@linux.intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1464818821-5736-5-git-send-email-daniel.vetter@ffwll.ch

The async name is deprecated and should be changed to nonblocking.

Cc: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: NMaarten Lankhorst <maarten.lankhorst@linux.intel.com>
Acked-by: NLaurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/1461679905-30177-8-git-send-email-maarten.lankhorst@linux.intel.com

Those formats are supported on Gen3 only.
Signed-off-by: NLaurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>

Document the R8A7795-specific DT bindings and support them in the
driver. The HDMI and LVDS outputs are currently not supported.
Signed-off-by: NKoji Matsuoka <koji.matsuoka.xm@renesas.com>
Signed-off-by: NLaurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>

On R-Car Gen3 SoCs the DU lost its ability to access memory directly and
needs to work in conjunction with the VSP to do so. This commit handles
the VSP internally to hide it from the user.
Signed-off-by: NLaurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>

The plane allocator is specific to DU planes and won't be used for
VSP-based planes, move it with the rest of the DU planes code where it
belongs.
Signed-off-by: NLaurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>

Configure the plane source at plane setup time to source frames from
memory or from the VSP1.
Signed-off-by: NLaurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>

The R8A7790 DU can source frames directly from the VSP1 devices VSPD0
and VSPD1. VSPD0 feeds DU0/1 plane 0, and VSPD1 feeds either DU2 plane 0
or DU0/1 plane 1.

Allocate the correct fixed plane when sourcing frames from VSPD0 or
VSPD1, and allocate planes in reverse index order otherwise to ensure
maximum availability of planes 0 and 1.
Signed-off-by: NLaurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>

A disabled CRTC can't display planes, the driver shouldn't try to
configure it when updating planes. The DRM core will store the plane
state for us, and the plane will be configured appropriately the next
time the CRTC is enabled.
Signed-off-by: NLaurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>

Drivers shouldn't clobber the passed in addfb ioctl parameters.
i915 was doing just that. To prevent it from happening again,
pass the struct around as const, starting all the way from
internal_framebuffer_create().
Signed-off-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

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: NThierry Reding <treding@nvidia.com>
Tested-by: NThierry Reding <treding@nvidia.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@intel.com>

When the .atomic_commit() handler fails, clean up planes previoulsy
prepared by drm_atomic_helper_prepare_planes() with a call to
drm_atomic_helper_cleanup_planes().
Signed-off-by: NLaurent Pinchart <laurent.pinchart@ideasonboard.com>

The function returns 1 on success, and either 0 or a negative error code
on failure. As the 0 and negative values don't need to be differentiated
by the caller, convert it to the usual scheme of returning 0 on success
and a negative error code on failure.
Signed-off-by: NLaurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>

A failure to initialize an encoder currently prints an error message in
the kernel log without mentioning which encoder failed to initialize. To
help debugging initialization issues print the encoder DT node name.

This requires moving the error message to the rcar_du_encoders_init_one
function and refactoring it slightly.
Signed-off-by: NLaurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>

Commit 917de180 ("drm: rcar-du: Implement universal plane support")
made the number of planes per group dynamic, but didn't update all loops
over the planes array, resulting in out-of-bound accesses on DU
instances that have an odd number of CRTCs (such as the R8A7790). Fix
it.

Fixes: 917de180 ("drm: rcar-du: Implement universal plane support")
Cc: stable@vger.kernel.org
Signed-off-by: NLaurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>

If we have more than one CRTCs in a group pre-associate planes 0-3 with
CRTC 0 and planes 4-7 with CRTC 1 to minimize flicker occurring when the
association is changed. The pre-association could be controlled by a
module parameter if needed.
Signed-off-by: NLaurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>

The number of CRTCs in a group is only used to implement plane
initialization for now, but is also needed to implement pre-association
of planes to CRTCs. Store it in the group structure instead of computing
it on demand.
Signed-off-by: NLaurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>

Hardware planes are driven by the timing generator of the CRTC they are
associated to. Changing the association requires restarting the CRTC
group that the plane belongs to, resulting in flicker on the other CRTC.

To avoid flicker as much as possible, try to allocate planes first from
the free planes already associated with the target CRTC. If allocation
fails then fall back to allocation from all free planes.
Signed-off-by: NLaurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>

Plane allocation is a complex process, add debugging statements to help
finding out what could might wrong.
Signed-off-by: NLaurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>

All other cast functions are named without using "du", make the plane
state cast consistent with them.
Signed-off-by: NLaurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>

The rcar_du_planes structure contains a single field and is only
instantiated in the rcar_du_group structure. Embed it directly and
remove the rcar_du_planes structure.
Signed-off-by: NLaurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>

The plane property objects are instantiated once per CRTC group, while
they should be instantiated once globally for the device. Fix this and
move them to the rcar_du_device structure.
Signed-off-by: NLaurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>

Using the for_each_... macro should make the code a bit shorter and
easier to read.
Signed-off-by: NPhilipp Zabel <p.zabel@pengutronix.de>
Acked-by: NLaurent Pinchart <laurent.pinchart@ideasonboard.com>

The plane allocator has been inherently racy since the beginning of the
transition to atomic updates, as the allocator lock is released between
free plane check (at .atomic_check() time) and the reservation (at
.atomic_update() time).

To fix it, create a new allocator solely based on the atomic plane
states without keeping any external state and perform allocation in the
.atomic_check() handler. The core idea is to replace the free planes
bitmask with a collective knowledge based on the allocated hardware
plane(s) for each KMS plane. The allocator then loops over all plane
states to compute the free planes bitmask, allocates hardware planes
based on that bitmask, and stores the result back in the plane states.

For this to work we need to access the current state of planes not
touched by the atomic update. To ensure that it won't be modified, we
need to lock all planes using drm_atomic_get_plane_state(). This
effectively serializes atomic updates from .atomic_check() up to
completion, either when swapping the states if the check step has
succeeded, or when freeing the states if the check step has failed.
Suggested-by: NDaniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: NLaurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>

As the DRM core will commit plane states when performing atomic updates,
those don't need to be committed manually when the CRTC is started except
in the system resume code path.

However, the atomic plane commit step is currently performed between
mode set disable and mode set enable to mimick the legacy mode setting
operations order. This causes the device clocks to be disabled after
applying plane settings and reenabled when enabling the CRTC,
potentially losing hardware in between.

Reorder the operations to enable the CRTC first and only then apply
plane settings, removing the need to manage clocks in the atomic begin
and flush handlers. We can then move the plane state commit code out of
the CRTC start handler to the system resume handler.
Signed-off-by: NLaurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>

Implement a custom .atomic_commit() handler that supports asynchronous
commits using a work queue. This can be used for userspace-driven
asynchronous commits, as well as for an atomic page flip implementation.
Signed-off-by: NLaurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>

This removes the legacy plane update code. Wire up the default atomic
check and atomic commit mode config helpers as needed by the plane
update atomic helpers.
Signed-off-by: NLaurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>

Hook up the default .reset(), .atomic_duplicate_state() and
.atomic_free_state() helpers to ensure that state objects are properly
created and destroyed, and call drm_mode_config_reset() at init time to
create the initial state objects.

Framebuffer reference count also gets maintained automatically by the
transitional helpers except for the legacy page flip operation. Maintain
it explicitly there.
Signed-off-by: NLaurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>

Explicitly create the CRTC primary plane instead of relying on the core
helpers to do so. This simplifies the plane logic by merging the KMS and
software planes.

Reject plane API operations on the primary planes for now, as that code
will anyway be refactored when implementing support for atomic updates.
Signed-off-by: NLaurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>

fbdev emulation requires at least one connector, and will fail to
initialize if no connector has been successfully instantiated. Disable
it in that case and print an informational message instead of failing
probe with a confusing fbdev emulation error message.

It could be argued that probe should fail when no connector is present,
but the DU could still be useful in that case with the to-be-implemented
memory write-back support.
Signed-off-by: NLaurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>

The function is meant to restore the fbdev mode in the lastclose
handler, not to be called at init time. Remove the call.
Signed-off-by: NLaurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>

All encoders and CRTCs start disabled, re-disabling them is a no-op.
Signed-off-by: NLaurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>

Decrementing the reference count of the previous endpoint node allows to
use the of_graph_get_next_endpoint function in a for_each_... style macro.
All current users of this function that pass a non-NULL prev parameter
(that is, soc_camera and imx-drm) are changed to not decrement the passed
prev argument's refcount themselves.
Signed-off-by: NPhilipp Zabel <p.zabel@pengutronix.de>
Acked-by: NMauro Carvalho Chehab <mchehab@osg.samsung.com>
Acked-by: NMathieu Poirier <mathieu.poirier@linaro.org>
Acked-by: NLaurent Pinchart <laurent.pinchart@ideasonboard.com>
Acked-by: NTomi Valkeinen <tomi.valkeinen@ti.com>

If an encoder fails to initialize the device can still be used without
the failed encoder. Don't propagate the error out of the probe function
but just skip the failed encoder.

As a special case a deferred probe request from the encoder is still
propagated out of the probe function in order not to break the deferred
probing mechanism.
Signed-off-by: NLaurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>

SoCs that integrate the DU have no internal HDMI encoder, support
external encoders only.
Signed-off-by: NLaurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>

The encoder DT node will be needed to register an external HDMI encoder.
Pass it to the rcar_du_encoder_init() function to prepare for HDMI
support.
Signed-off-by: NLaurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>

All platforms now instantiate the DU through DT, platform data support
isn't needed anymore.
Signed-off-by: NLaurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>

When creating a dumb buffer object using the DRM_IOCTL_MODE_CREATE_DUMB
IOCTL, only the width, height, bpp and flags fields are inputs. The
caller is not guaranteed to zero out or set handle, pitch and size.
Drivers must not treat these values as possible inputs, otherwise they
may use uninitialized memory during the computation of the framebuffer
size.

The R-Car DU driver treats the pitch passed in from userspace as minimum
and will only overwrite it when the driver-computed pitch is larger,
allowing userspace to, intentionally or not, overallocate framebuffers.

Cc: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Reviewed-by: NDaniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: NThierry Reding <treding@nvidia.com>