It's silly to have 2 mallocs when we could tie these two together.
Also, Gustavo adds another one in his per-crtc out-fence patches. And
I want to add more stuff here for nonblocking commit helpers.
In the future we can use this to store a pointer to the preceeding
state, making an atomic update entirely free-standing. This will be
needed to be able to queue them up with a depth > 1.
Cc: Gustavo Padovan <gustavo@padovan.org>
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/1464818821-5736-12-git-send-email-daniel.vetter@ffwll.ch
It's kinda pointless to have 2 separate mallocs for these. And when we
add more per-plane state in the future it's even more pointless.
Right now there's no such thing planned, but both Gustavo's per-crtc
fence patches, and some nonblocking commit helpers I'm playing around
with will add more per-crtc stuff. It makes sense to also consolidate
planes, just for consistency.
In the future we can use this to store a pointer to the preceeding
state, making an atomic update entirely free-standing. This will be
needed to be able to queue them up with a depth > 1.
Cc: Gustavo Padovan <gustavo@padovan.org>
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/1464818821-5736-11-git-send-email-daniel.vetter@ffwll.ch
It's kinda pointless to have 2 separate mallocs for these. And when we
add more per-connector state in the future it's even more pointless.
Right now there's no such thing planned, but both Gustavo's per-crtc
fence patches, and some nonblocking commit helpers I'm playing around
with will add more per-crtc stuff. It makes sense to also consolidate
connectors, just for consistency.
In the future we can use this to store a pointer to the preceeding
state, making an atomic update entirely free-standing. This will be
needed to be able to queue them up with a depth > 1.
Cc: Gustavo Padovan <gustavo@padovan.org>
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/1464818821-5736-10-git-send-email-daniel.vetter@ffwll.ch
drm_atomic_set_mode_prop_for_crtc() does not clear the state->mode, so
old data may be left there when a new mode is set, possibly causing odd
issues.
This patch improves the situation by always clearing the state->mode
first.
Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ti.com>
Cc: stable@vger.kernel.org
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Dave Airlie <airlied@redhat.com>
Whilst looking at the fallout from using connector references for
atomic, I noticed that there is an early return buried in
drm_atomic_set_crtc_for_connector() that if hit could cause us to leak a
reference on the connector.
Fixes: d2307dea14 (drm/atomic: use connector references (v3))
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Daniel Stone <daniels@collabora.com>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: Dave Airlie <airlied@redhat.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/1462535265-13058-1-git-send-email-chris@chris-wilson.co.uk
Take a reference when setting a crtc on a connecter,
also take one when duplicating if a crtc is set,
and drop one on destroy if a crtc is set.
v2: take Daniel Stone's advice and simplify the
ref/unref dances, also take care of NULL as connector
to state reset.
v3: remove need for connector NULL check.
Reviewed-by: Daniel Stone <daniels@collabora.com>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Dave Airlie <airlied@redhat.com>
This uses the previous changes to add reference counts
to drm connector objects.
v2: move fbdev changes to their own patch.
add some kerneldoc
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Reviewed-by: Daniel Stone <daniels@collabora.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>
When I was writing an atomic wrapper for rmfb, I ran into the
following backtrace from lockdep:
=============================================
[ INFO: possible recursive locking detected ]
4.5.0-patser+ #4696 Tainted: G U
---------------------------------------------
kworker/2:2/2608 is trying to acquire lock:
(crtc_ww_class_mutex){+.+.+.}, at: [<ffffffffc00c9ddc>] drm_modeset_lock+0x7c/0x120 [drm]
but task is already holding lock:
(crtc_ww_class_mutex){+.+.+.}, at: [<ffffffffc00c98cd>] modeset_backoff+0x8d/0x220 [drm]
other info that might help us debug this:
Possible unsafe locking scenario:
CPU0
----
lock(crtc_ww_class_mutex);
lock(crtc_ww_class_mutex);
*** DEADLOCK ***
May be due to missing lock nesting notation
4 locks held by kworker/2:2/2608:
#0: ("events"){.+.+.+}, at: [<ffffffff810a5eea>] process_one_work+0x15a/0x6c0
#1: ((&arg.work)){+.+.+.}, at: [<ffffffff810a5eea>] process_one_work+0x15a/0x6c0
#2: (crtc_ww_class_acquire){+.+.+.}, at: [<ffffffffc004532a>] drm_atomic_helper_remove_fb+0x4a/0x1d0 [drm_kms_helper]
#3: (crtc_ww_class_mutex){+.+.+.}, at: [<ffffffffc00c98cd>] modeset_backoff+0x8d/0x220 [drm]
While lockdep probably catches this bug when it happens, it's better
to explicitly warn when state->acquire_ctx is not set.
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/1462266751-29123-1-git-send-email-maarten.lankhorst@linux.intel.com
Bunch of small fixupes all over. Plus a dma-buf patch that Sumit asked me
to cherry-pick since that's the only one he had in his tree.
There's a sparse issue outstanding in the color mgr stuff, but Lionel is
still working on something that actually appeases sparse.
* tag 'topic/drm-misc-2016-03-22' of git://anongit.freedesktop.org/drm-intel:
dma-buf/fence: fix fence_is_later v2
dma-buf: Update docs for SYNC ioctl
drm: remove excess description
dma-buf, drm, ion: Propagate error code from dma_buf_start_cpu_access()
drm/atmel-hlcdc: use helper to get crtc state
drm/atomic: use helper to get crtc state
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
Because we record connector_mask using 1 << drm_connector_index now
the connector_mask should stay the same even when other connectors
are removed. This was not the case with MST, in that case when removing
a connector all other connectors may change their index.
This is fixed by waiting until the first get_connector_state to allocate
connector_state, and force reallocation when state is too small.
As a side effect connector arrays no longer have to be preallocated,
and can be allocated on first use which means a less allocations in
the page flip only path.
Changes since v1:
- Whitespace. (Ville)
- Call ida_remove when destroying the connector. (Ville)
- u32 alloc -> int. (Ville)
Fixes: 14de6c44d1 ("drm/atomic: Remove drm_atomic_connectors_for_crtc.")
Signed-off-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: Lyude <cpaul@redhat.com>
Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>
An attempt at not spreading out the file_priv->event_space stuff out
quite so far and wide. And I think fixes something in ipp_get_event()
that is broken (or if they are doing something more weird/subtle, then
breaks it in a fun way).
Based upon a patch from Rob Clark, rebased and polished.
v2: Spelling fixes (Alex).
Cc: Alex Deucher <alexdeucher@gmail.com>
Acked-by: Daniel Stone <daniels@collabora.com>
Reviewed-by: Alex Deucher <alexander.deucher@amd.com>
Cc: Rob Clark <robdclark@gmail.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1452548477-15905-3-git-send-email-daniel.vetter@ffwll.ch
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
We want this for consistency with existing page_flip semantics.
Since this spurred quite a discussion on IRC also document why we
reject event generation when the pipe is off: It's not that it's hard
to implement, but userspace has a track recording which proves that it's
way too easy to accidentally abuse and cause havoc. We want to make
sure userspace doesn't get away with that.
v2: Somehow thought we do reject events already, but that code only
existed in my imagination ... Also suggestions from Thierry.
Cc: Daniel Stone <daniels@collabora.com>
Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
Cc: Thierry Reding <thierry.reding@gmail.com>
Reviewed-by: Daniel Stone <daniels@collabora.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/1449564561-3896-4-git-send-email-daniel.vetter@ffwll.ch
Show a sensible name for the plane in debug mesages. The driver
may supply its own name, otherwise the core genrates the name
("plane-0", "plane-1" etc.).
v2: kstrdup() the name passed by the caller (Jani)
v3: Generate a default name if the driver doesn't supply one
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/1449592922-5545-7-git-send-email-ville.syrjala@linux.intel.com
Show a sensible name for the crtc in debug mesages. The driver may
supply its own name, otherwise the core genrates the name
("crtc-0", "crtc-1" etc.).
v2: kstrdup() the name passed by the caller (Jani)
v3: Generate a default name if the driver doesn't supply one
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/1449592922-5545-6-git-send-email-ville.syrjala@linux.intel.com
Yes these are internal functions and not exported and we generally
don't document them. But for symmetry with the _set_property functions
(which are exported for the atomic helpers) I'd like to document them.
Upcoming vtable kerneldoc will reference both the set and get_property
functions.
v2: Suggestions from Thierry.
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Reviewed-by: Thierry Reding <treding@nvidia.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1449218769-16577-17-git-send-email-daniel.vetter@ffwll.ch
This function is like drm_modeset_lock_all(), but it takes the lock
acquisition context as a parameter rather than storing it in the DRM
device's mode_config structure.
Implement drm_modeset_{,un}lock_all() in terms of the new function for
better code reuse, and add a note to the kerneldoc that new code should
use the new functions.
v2: improve kerneldoc
v4: rename drm_modeset_lock_all_crtcs() to drm_modeset_lock_all_ctx()
and take mode_config's .connection_mutex instead of .mutex lock to
avoid lock inversion (Daniel Vetter), use drm_modeset_drop_locks()
which is now the equivalent of drm_modeset_unlock_all_ctx()
v5: do not take the dev->mode_config.connection_mutex in
drm_atomic_legacy_backoff() since drm_modeset_lock_all_ctx()
already keeps it, enhance kerneldoc for drm_modeset_lock_all_ctx()
(Daniel Vetter)
Signed-off-by: Thierry Reding <treding@nvidia.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1449075005-13937-1-git-send-email-thierry.reding@gmail.com
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Use the correct function name for drm_atomic_clean_old_fb docs.
Signed-off-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
The drm_property_unreference_blob() function tests whether its argument
is NULL and then returns immediately.
Thus the tests around the calls are not needed.
This issue was detected by using the Coccinelle software.
Signed-off-by: Markus Elfring <elfring@users.sourceforge.net>
Link: http://patchwork.freedesktop.org/patch/msgid/563C8B3E.405@users.sourceforge.net
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
plane_mask should be cleared inside the retry loop, because it gets
reset on every retry. Without this fix the plane->fb refcounting might
get out of sync on retries, resulting in either leaked memory or
use-after-free.
Signed-off-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Cc: stable@vger.kernel.org #v4.3
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1447237751-9663-3-git-send-email-maarten.lankhorst@ubuntu.com
Fixes the following sparse warning:
drivers/gpu/drm/drm_atomic.c:442:5: warning: symbol
'drm_atomic_crtc_get_property' was not declared. Should it be static?
Signed-off-by: Geliang Tang <geliangtang@163.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
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Merge tag 'v4.3-rc2' into topic/drm-misc
Backmerge Linux 4.3-rc2 because of conflicts in the dp helper code
between bugfixes and new code. Just adjacent lines really.
On top of that there's a silent conflict in the new fsl-dcu driver
merged into 4.3 and
commit 844f9111f6
Author: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Date: Wed Sep 2 10:42:40 2015 +0200
drm/atomic: Make prepare_fb/cleanup_fb only take state, v3.
which Thierry Reding spotted and provided a fixup for.
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Very strictly speaking this is possible if you have special hw and
genlocked CRTCs. In general switching a plane between two active CRTC
just won't work so well and is probably not tested at all. Just forbid
it.
I've put this into the core since right now no helper or driver copes
with it, no userspace has code for it and no one asks for it. Yes
there's piles of corner-cases where this would be possible to do this
like:
- switch from inactive crtc to active crtc
- switch from active crtc to inactive crtc
- genlocked display
- invisible plane (to do whatever)
- idle plane hw due to dsi cmd mode/psr
- whatever
but looking at details it's not that easy to implement this correctly.
Hence just put it into the core and add a comment, since the only
userspace we have right now for atomic (weston) doesn't want to use
direct plane switching either.
v2: don't bother with complexity and just outright disallow plane
switching without the intermediate OFF state. Simplifies drivers, we
don't have any hw that could do it anyway and current atomic userspace
(weston) works like this already anyway.
v3: Bikeshed function name (Ville) and add comment (Rob).
v4: Also bikeshed commit message (Rob).
v5: Fix compile warnings reported by 0-day.
Cc: Thierry Reding <thierry.reding@gmail.com>
Cc: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Cc: Daniel Stone <daniels@collabora.com>
Acked-by: Daniel Stone <daniels@collabora.com>
Reviewed-by: Rob Clark <robdclark@gmail.com>
Acked-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Commit ec9f932ed4
"drm/atomic: Cleanup on error properly in the atomic ioctl."
cleaned up some error paths, but didn't fix the TEST_ONLY path.
In the check only case plane->fb shouldn't be updated, and
the vblank events should be cleared as on failure.
Changes since v1:
- Fix -EDEADLK handling of vblank events too.
- Free state last with CHECK_ONLY.
Changes since v2:
- Add comment about freeing crtc_state->event with TEST_ONLY.
(Daniel Stone)
Signed-off-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Reviewed-by: Daniel Stone <daniels@collabora.com>
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
This reverts commit 992cbf19b3.
Until we make fbdev layer atomic we can't call this.
Requested-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com?
Acked-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Dave Airlie <airlied@redhat.com>
We want to make sure that no one tries to acquire more locks and
states, and ww mutexes provide debug facilities for that. So use them.
v2: Only call acquire_done when ->atomic_check was successful to avoid
falling over an -EDEADLK (spotted by Maarten).
Cc: Rob Clark <robdclark@gmail.com>
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>
In
commit 6f75cea66c
Author: Daniel Vetter <daniel.vetter@ffwll.ch>
Date: Wed Nov 19 18:38:07 2014 +0100
drm/atomic: Only destroy connector states with connection mutex held
I tried to fix races of atomic commits against connector
hot-unplugging. The idea is to ensure lifetimes by holding the
connection_mutex long enough. That works for synchronous commits, but
not for async ones.
For async atomic commit we really need to fix up connector lifetimes
for real. But that's a much bigger task, so just add more duct-tape:
For cleaning up connector states we currently don't need the connector
itself. So NULL it out and remove the locking check. Of course that
check was to protect the entire sequence, but the modeset itself
should be save since currently DP MST hot-removal does a dpms-off. And
that should synchronize with any outstanding async atomic commit.
Or at least that's my hope, this is all a giant mess.
Reported-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
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>
connector hotplug locking cleanup and fixes to make it save against
atomic. Note that because of depencies this is based on top of the
drm-intel-next pull, so that one needs to go in before this one.
I've also thrown in the mode_group removal on top since it's defunct,
never worked really, no one seems to care and the code can be resurrected
easily.
* tag 'topic/connector-locking-2015-07-23' of git://anongit.freedesktop.org/drm-intel:
drm: gc now dead mode_group code
drm: Stop filtering according to mode_group in getresources
drm: Roll out drm_for_each_{plane,crtc,encoder}
drm/cma-helper: Fix locking in drm_fb_cma_debugfs_show
drm: Roll out drm_for_each_connector more
drm: Amend connector list locking rules
drm/radeon: Take all modeset locks for DP MST hotplug
drm/i915: Take all modeset locks for DP MST hotplug
drm: Check locking in drm_for_each_fb
drm/i915: Use drm_for_each_fb in i915_debugfs.c
drm: Check locking in drm_for_each_connector
drm/fbdev-helper: Grab mode_config.mutex in drm_fb_helper_single_add_all_connectors
drm/probe-helper: Grab mode_config.mutex in poll_init/enable
drm: Add modeset object iterators
drm: Simplify drm_for_each_legacy_plane arguments
Now that we also grab the connection_mutex and so fixed the race with
atomic modeset we can use the iterator there too.
The other special case is drm_connector_unplug_all which would have a
locking inversion with the sysfs store/show functions if we'd grab the
mode_config.mutex around the unplug. We could just grab
connection_mutex instead, but that's a bit too much a dirty trick for
my taste. Also it's only used by udl, which doesn't do any other kind
of connector hotplugging, so should be race-free. Hence just stick
with a comment for now.
Reviewed-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
It's probably allowed to leave old_fb set to garbage when unlocking,
but to prevent undefined behavior unset it just in case.
Also crtc_state->event could be NULL on memory allocation failure,
in which case event_space is increased for no reason.
Note: Contains some general simplification of the cleanup code too.
Signed-off-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
[danvet: Add note about the other changes in here. And fix long line
while at it.]
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
This change updates the old_fb pointer only after acquiring the plane lock,
if there are no properties the fb cannot have been changed either, so
this works out correctly.
Found in a discussion with Rob Clark.
Cc: Rob Clark <robdclark@gmail.com>
Signed-off-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Reviewed-by: Rob Clark <robdclark@gmail.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
We use the same check already in the atomic core, so might as well
make this official. And it's also reused in e.g. i915.
Motivated by Maarten's idea to extract a connector_changed state out
of mode_changed.
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>
Atomic modesetting: now with modesetting support.
v2: Moved drm_atomic_set_mode_prop_for_crtc from previous patch; removed
state->active fiddling, documented return code. Changed property
type to DRM_MODE_PROP_BLOB.
Signed-off-by: Daniel Stone <daniels@collabora.com>
Tested-by: Sean Paul <seanpaul@chromium.org>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Add a blob property tracking the current mode to the CRTC state, and
ensure it is properly updated and referenced.
v2: Continue using crtc_state->mode inside getcrtc, instead of reading
out the mode blob. Use IS_ERR and PTR_ERR from create_blob. Move
set_mode_prop_for_crtc to later patch where it actually gets used.
Enforce !!state->enable == !!state->mode_blob inside
drm_atomic_crtc_check.
Signed-off-by: Daniel Stone <daniels@collabora.com>
Tested-by: Sean Paul <seanpaul@chromium.org>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Add a new helper, to be used later for blob property management, that
sets the mode for a CRTC state, as well as updating the CRTC enable/active
state at the same time.
v2: Do not touch active/mode_changed in CRTC state. Document return
value. Remove stray drm_atomic_set_mode_prop_for_crtc declaration.
v3: Remove i915 changes, and leave it directly bashing crtc_state->mode
for the meantime.
Signed-off-by: Daniel Stone <daniels@collabora.com>
Tested-by: Sean Paul <seanpaul@chromium.org>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
This is a convenience function to add all planes for a crtc,
similar to add_affected_connectors. This will be used in
drm_atomic_helper_check_modeset, but drivers can call it too
when they need to recalculate all state.
Signed-off-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
[danvet: Amend kerneldoc a bit.]
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Drivers may need to store the state of shared resources, such as PLLs
or FIFO space, into the atomic state. Allow this by making it possible
to subclass drm_atomic_state.
Changes since v1:
- Change member names for functions to atomic_state_(alloc,clear)
- Change __drm_atomic_state_new to drm_atomic_state_init
- Allow free function to be overridden too, in case extra memory is
allocated in alloc.
Changes since v2:
- Rename *_default_free to default_release, to make clear it doesn't
free the state object itself.
Cc: dri-devel@lists.freedesktop.org
Acked-by: Ander Conselvan de Oliveira <ander.conselvan.de.oliveira@intel.com>
Signed-off-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
There are cases where we want to test if a given object is
part of the state, but don't want to add them if they're not.
Signed-off-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
This saves some typing whenever a iteration over all the connector,
crtc or plane states in the atomic state is written, which happens
quite often.
Cc: dri-devel@lists.freedesktop.org
Signed-off-by: Ander Conselvan de Oliveira <ander.conselvan.de.oliveira@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Consistently with other free functions, handle the NULL case without
oopsing.
Cc: dri-devel@lists.freedesktop.org
Signed-off-by: Ander Conselvan de Oliveira <ander.conselvan.de.oliveira@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Users of the atomic state assume that if the pointer to a crtc, plane or
connector is not NULL in the respective object vector, than the state
for that object in *_states vector also won't be NULL. That assumption
was broken by drm_atomic_state_clear(), which would clear the state
pointer but leave the pointer to the object still set.
This fixes a NULL pointer dereference in i915 caused by the use of
drm_atomic_state_clear().
Cc: dri-devel@lists.freedesktop.org
Signed-off-by: Ander Conselvan de Oliveira <ander.conselvan.de.oliveira@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Before, we would set the property, but also return -EINVAL because of a
broken fallthrough.
Signed-off-by: Daniel Stone <daniels@collabora.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Active was here, and we allowed users to set it, but not to get it as
well.
Signed-off-by: Daniel Stone <daniels@collabora.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Both the legacy and atomic helpers need to check whether a plane
supports a given pixel format. The code is currently duplicated, share
it.
Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
[danvet: Slightly extend the docbook.]
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Commit 1da30627fc "drm: Add rotation value to
plane state" moved the rotation property to DRM core but only did the set
property part. This does the get property part as well.
Signed-off-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Cc: Matt Roper <matthew.d.roper@intel.com>
Cc: dri-devel@lists.freedesktop.org
Reviewed-by: Matt Roper <matthew.d.roper@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Atomic state handling adds a lot of indirection and complexity between
simple updates and drivers. For easier debugging the diagnostic output
is therefore rather chatty. Which is great for tracking down atomic
issues, but really annoying otherwise.
Add a new DRM_DEBUG_ATOMIC to be able to filter this out.
Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: Rob Clark <robdclark@gmail.com>
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
The atomic helpers rely on drm_atomic_state_clear() to reset an atomic
state if a retry is needed due to the w/w mutexes. The subsequent calls
to drm_atomic_get_{crtc,plane,...}_state() would then return the stale
pointers in state->{crtc,plane,...}_states.
Signed-off-by: Ander Conselvan de Oliveira <ander.conselvan.de.oliveira@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
This is the infrastructure for DPMS ported to the atomic world.
Fundamental changes compare to legacy DPMS are:
- No more per-connector dpms state, instead there's just one per each
display pipeline. So if you clone either you have to unclone first
if you only want to switch off one screen, or you just switch of
everything (like all desktops do). This massively reduces complexity
for cloning since now there's no more half-enabled cloned configs to
consider.
- Only on/off, dpms standby/suspend are as dead as real CRTs. Again
reduces complexity a lot.
Now especially for backwards compat the really important part for dpms
support is that dpms on always succeeds (except for hw death and
unplugged cables ofc). Which means everything that could fail (like
configuration checking, resources assignments and buffer management)
must be done irrespective from ->active. ->active is really only a
toggle to change the hardware state. More precisely:
- Drivers MUST NOT look at ->active in their ->atomic_check callbacks.
Changes to ->active MUST always suceed if nothing else changes.
- Drivers using the atomic helpers MUST NOT look at ->active anywhere,
period. The helpers will take care of calling the respective
enable/modeset/disable hooks as necessary. As before the helpers
will carefully keep track of the state and not call any hooks
unecessarily, so still no double-disables or enables like with crtc
helpers.
- ->mode_set hooks are only called when the mode or output
configuration changes, not for changes in ->active state.
- Drivers which reconstruct the state objects in their ->reset hooks
or through some other hw state readout infrastructure must ensure
that ->active reflects actual hw state.
This just implements the core bits and helper logic, a subsequent
patch will implement the helper code to implement legacy dpms with
this.
v2: Rebase on top of the drm ioctl work:
- Move crtc checks to the core check function.
- Also check for ->active_changed when deciding whether a modeset
might happen (for the ALLOW_MODESET mode).
- Expose the ->active state with an atomic prop.
v3: Review from Rob
- Spelling fix in comment.
- Extract needs_modeset helper to consolidate the ->mode_changed ||
->active_changed checks.
v4: Fixup fumble between crtc->state and crtc_state.
Cc: Rob Clark <robdclark@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>
The rotation property is shared by multiple drivers, so it makes sense
to store the rotation value (for atomic-converted drivers) in the common
plane state so that core code can eventually access it as well.
Cc: dri-devel@lists.freedesktop.org
Suggested-by: Daniel Vetter <daniel@ffwll.ch>
Reviewed-by: Thierry Reding <treding@nvidia.com>
Signed-off-by: Matt Roper <matthew.d.roper@intel.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>
Copying 64 bit data from user space using get_user is not supported
on all architectures, and may result in the following build error.
ERROR: "__get_user_bad" [drivers/gpu/drm/drm.ko] undefined!
Avoid the problem by using copy_from_user.
Fixes: d34f20d6e2 ("drm: Atomic modeset ioctl")
Cc: Rob Clark <robdclark@gmail.com>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
This is just a bit fallout from patch polishing and moving the
get_prop logic fully into the core:
- Drop EXPORT_SYMBOL and make the helpers static.
- Drop kerneldoc since not used by drivers.
- Move the cross-file function declarations only used by drm.ko
internally to an internal header.
v2: keep the gist of the comments, requested by Rob.
Cc: Rob Clark <robdclark@gmail.com>
Reviewed-by: Rob Clark <robdclark@gmail.com>
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
The atomic modeset ioctl can be used to push any number of new values
for object properties. The driver can then check the full device
configuration as single unit, and try to apply the changes atomically.
The ioctl simply takes a list of object IDs and property IDs and their
values.
Originally based on a patch from Ville Syrjälä, although it has mutated
(mutilated?) enough since then that you probably shouldn't blame it on
him ;-)
The atomic support is hidden behind the DRM_CLIENT_CAP_ATOMIC cap (to
protect legacy userspace) and drm.atomic module param (for now).
v2: Check for file_priv->atomic to make sure we only allow userspace
in-the-know to use atomic.
Signed-off-by: Rob Clark <robdclark@gmail.com>
Reviewed-by: Sean Paul <seanpaul@chromium.org>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Expose the core connector state as properties so it can be updated via
atomic ioctl.
Signed-off-by: Rob Clark <robdclark@gmail.com>
Reviewed-by: Sean Paul <seanpaul@chromium.org>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Expose the core plane state as properties, so they can be updated via
atomic ioctl.
v2: atomic property flag
Signed-off-by: Rob Clark <robdclark@gmail.com>
Reviewed-by: Sean Paul <seanpaul@chromium.org>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Add functions to check core plane/crtc state.
v2: comments, int-overflow checks, call from core rather than
helpers to be sure drivers can't find a way to bypass core
checks
Signed-off-by: Rob Clark <robdclark@gmail.com>
Reviewed-by: Sean Paul <seanpaul@chromium.org>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Once a driver is using atomic helpers for modeset, the next step is to
switch over to atomic properties. To do this, make sure that any
modeset objects have their ->atomic_{get,set}_property() vfuncs suitably
populated if they have custom properties (you did already remember to
plug in atomic-helper func for the legacy ->set_property() vfuncs,
right?), and then set DRIVER_ATOMIC bit in driver_features flag.
A new cap is introduced, DRM_CLIENT_CAP_ATOMIC, for the purposes of
shielding legacy userspace from atomic properties. Mostly for the
benefit of legacy DDX drivers that do silly things like getting/setting
each property at startup (since some of the new atomic properties will
be able to trigger modeset).
Signed-off-by: Rob Clark <robdclark@gmail.com>
[danvet: Squash in fixup patch to check for DRM_MODE_PROP_ATOMIC
instaed of the CAP define when filtering properties. Reported by
Tvrtko Uruslin, acked by Rob.]
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Since we won't be using the obj->properties->values[] array to shadow
property values for atomic drivers, we are going to need a vfunc for
getting prop values. Add that along w/ mandatory wrapper fxns.
v2: more comments and copypasta comment typo fix
Signed-off-by: Rob Clark <robdclark@gmail.com>
Reviewed-by: Sean Paul <seanpaul@chromium.org>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
As we add properties for all the standard plane/crtc/connector
attributes (in preperation for the atomic ioctl), we are going to want
to handle core state in core (rather than per driver). Intercepting the
core properties will be easier if the atomic_set_property vfuncs are not
called directly, but instead have a mandatory wrapper function (which
will later serve as the point to intercept core properties).
v2: more verbose comments and copypasta comment fix
Signed-off-by: Rob Clark <robdclark@gmail.com>
Reviewed-by: Sean Paul <seanpaul@chromium.org>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Useful since this way we can pass around just the state objects and
will get ther real object, too.
Specifically this allows us to again simplify the parameters for
set_crtc_for_plane.
v2: msm already has it's own specific plane_reset hook, don't forget
that one!
v3: Fixup kerneldoc, reported by 0-day builder.
Cc: Rob Clark <robdclark@gmail.com>
Reviewed-by: Rob Clark <robdclark@gmail.com> (v2)
Tested-by: Rob Clark <robdclark@gmail.com> (v2)
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Chasing plane->state->crtc of planes that are *not* part of the same
atomic update is racy, making it incredibly awkward (or impossible) to
do something simple like iterate over all planes and figure out which
ones are attached to a crtc.
Solve this by adding a bitmask of currently attached planes in the
crtc-state.
Note that the transitional helpers do not maintain the plane_mask. But
they only support the legacy ioctls, which have sufficient brute-force
locking around plane updates that they can continue to loop over all
planes to see what is attached to a crtc the old way.
Signed-off-by: Rob Clark <robdclark@gmail.com>
[danvet:
- Drop comments about locking in set_crtc_for_plane since they're a
bit misleading - we already should hold lock for the current crtc.
- Also WARN_ON if get_state on the old crtc fails since that should
have been done already.
- Squash in fixup to check get_plane_state return value, reported by
Dan Carpenter and acked by Rob Clark.]
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
I've forgotten to remove that in my per-plane locking patch.
Reported-by: Rob Clark <robdclark@gmail.com>
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
This is an oversight from
commit f52b69f1ec
Author: Daniel Vetter <daniel.vetter@ffwll.ch>
Date: Wed Nov 19 18:38:08 2014 +0100
drm/atomic: Don't overrun the connector array when hotplugging
Cc: Dave Airlie <airlied@redhat.com>
Cc: Rob Clark <robdclark@gmail.com>
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Reviewed-by: Thierry Reding <treding@nvidia.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>
Yet another fallout from not considering DP MST hotplug. With the
previous patches we have stable indices, but it might still happen
that a connector gets added between when we allocate the array and
when we actually add a connector. Especially when we back off due to
ww mutex contention or similar issues.
So store the sizes of the arrays in struct drm_atomic_state and double
check them. We don't really care about races except that we want to
use a consistent value, so ACCESS_ONCE is all we need. And if we
indeed notice that we'd overrun the array then just give up and
restart the entire ioctl.
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Reviewed-by: Rob Clark <robdclark@gmail.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>
Otherwise the connector might have been unplugged and destroyed while
we didn't look. Yet another fallout from DP MST hotplugging that I
didn't consider.
To make sure we get this right add an appropriate WARN_ON to
drm_atomic_state_clear (obviously only when we actually have a state
to clear up). And reorder all the state_clear and backoff calls to
make it work out properly.
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Reviewed-by: Rob Clark <robdclark@gmail.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>
I've totally forgotten that with DP MST connectors can now be
hotplugged. And failed to adapt Rob's drm_atomic_state code (which
predates connector hotplugging) to the new realities.
The first step is to make sure that the connector indices used to
access the arrays of pointers are stable. The connection mutex gives
us enough guarantees for that, which means we won't unecessarily block
on concurrent modesets or background probing.
So add a locking WARN_ON and shuffle the code slightly to make sure we
always hold the right lock.
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Reviewed-by: Rob Clark <robdclark@gmail.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>
Turned out to be much simpler on top of my latest atomic stuff than
what I've feared. Some details:
- Drop the modeset_lock_all snakeoil in drm_plane_init. Same
justification as for the equivalent change in drm_crtc_init done in
commit d0fa1af40e
Author: Daniel Vetter <daniel.vetter@ffwll.ch>
Date: Mon Sep 8 09:02:49 2014 +0200
drm: Drop modeset locking from crtc init function
Without these the drm_modeset_lock_init would fall over the exact
same way.
- Since the atomic core code wraps the locking switching it to
per-plane locks was a one-line change.
- For the legacy ioctls add a plane argument to the locking helper so
that we can grab the right plane lock (cursor or primary). Since the
universal cursor plane might not be there, or someone really crazy
might forgoe the primary plane even accept NULL.
- Add some locking WARN_ON to the atomic helpers for good paranoid
measure and to check that it all works out.
Tested on my exynos atomic hackfest with full lockdep checks and ww
backoff injection.
v2: I've forgotten about the load-detect code in i915.
v3: Thierry reported that in latest 3.18-rc vmwgfx doesn't compile any
more due to
commit 21e88620aa
Author: Rob Clark <robdclark@gmail.com>
Date: Thu Oct 30 13:39:04 2014 -0400
drm/vmwgfx: fix lock breakage
Rebased and fix this up.
Cc: Thierry Reding <thierry.reding@gmail.com>
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Reviewed-by: Sean Paul <seanpaul@chromium.org>
Signed-off-by: Dave Airlie <airlied@redhat.com>
So my original plan was that the drm core refcounts framebuffers like
with the legacy ioctls. But that doesn't work for a bunch of reasons:
- State objects might live longer than until the next fb change
happens for a plane. For example delayed cleanup work only happens
_after_ the pageflip ioctl has completed. So this definitely doesn't
work without the plane state holding its own references.
- The other issue is transition from legacy to atomic implementations,
where the driver works under a mix of both worlds. Which means
legacy paths might not properly update the ->fb pointer under
plane->state->fb. Which is a bit a problem when then someone comes
around and _does_ try to clean it up when it's long gone.
The second issue is just a bit a transition bug, since drivers should
update plane->state->fb in all the paths that aren't converted yet.
But a bit more robustness for the transition can't hurt - we pull
similar tricks with cleaning up the old fb in the transitional helpers
already.
The pattern for drivers that transition is
if (plane->state)
drm_atomic_set_fb_for_plane(plane->state, plane->fb);
inserted after the fb update has logically completed at the end of
->set_config (or ->set_base/mode_set if using the crtc helpers),
->page_flip, ->update_plane or any other entry point which updates
plane->fb.
v2: Update kerneldoc - copypasta fail.
v3: Fix spelling in the commit message (Sean).
Reviewed-by: Sean Paul <seanpaul@chromium.org>
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Some differences compared to Rob's patches again:
- Dropped the committed and checked booleans. Checking will be
internally enforced by always calling ->atomic_check before
->atomic_commit. And async handling needs to be solved differently
because the current scheme completely side-steps ww mutex deadlock
avoidance (and so either reinvents a new deadlock avoidance wheel or
like the current code just deadlocks).
- State for connectors needed to be added, since now they have a
full-blown drm_connector_state (so that drivers have something to
attach their own stuff to).
- Refcounting is gone. I plane to solve async updates differently,
since the lock-passing scheme doesn't cut it (since it abuses ww
mutexes). Essentially what we need for async is a simple ownership
transfer from the caller to the driver. That doesn't need full-blown
refcounting.
- The acquire ctx is a pointer. Real atomic callers should have that
on their stack, legacy entry points need to put the right one
(obtained by drm_modeset_legacy_acuire_ctx) in there.
- I've dropped all hooks except check/commit. All the begin/end
handling is done by core functions and is the same.
- commit/check are just thin wrappers that ensure that ->check is
always called.
- To help out with locking in the legacy implementations I've added a
helper to just grab all locks in the backoff case.
v2: Add notices that check/commit can fail with EDEADLK.
v3:
- More consistent naming for state_alloc.
- Add state_clear which is needed for backoff and retry.
v4: Planes/connectors can switch between crtcs, and we need to be
careful that we grab the state (and locks) for both the old and new
crtc. Improve the interface functions to ensure this.
v5: Add functions to grab affected connectors for a crtc and to recompute
the crtc->enable state. This is useful for both helper and atomic ioctl
code when e.g. removing a connector.
v6: Squash in fixup from Fengguang to use ERR_CAST.
v7: Add debug output.
v8: Make checkpatch happy about kcalloc argument ordering.
v9: Improve kerneldoc in drm_crtc.h
v10:
- Fix another kcalloc argument misorder I've missed.
- More polish for kerneldoc.
v11: Clarify the ownership rules for the state object. The new rule is
that a successful drm_atomic_commit (whether synchronous or asnyc)
always inherits the state and is responsible for the clean-up. That
way async and sync ->commit functions are more similar.
v12: A few bugfixes:
- Assign state->state pointers correctly when grabbing state objects -
we need to link them up with the global state.
- Handle a NULL crtc in set_crtc_for_plane to simplify code flow a bit
for the callers of this function.
v13: Review from Sean:
- kerneldoc spelling fixes
- Don't overallocate states->planes.
- Handle NULL crtc in set_crtc_for_connector.
v14: Sprinkle __must_check over all functions which do wait/wound
locking to make sure callers don't forget this. Since I have ;-)
v15: Be more explicit in the kerneldoc when functions can return
-EDEADLK what to do. And that every other -errno is fatal.
v16: Indent with tabs instead of space, spotted by Ander.
v17: Review from Thierry, small kerneldoc and other naming polish.
Cc: Thierry Reding <thierry.reding@gmail.com>
Cc: Ander Conselvan de Oliveira <conselvan2@gmail.com>
Cc: Daniel Thompson <daniel.thompson@linaro.org>
Cc: Fengguang Wu <fengguang.wu@intel.com>
Cc: Sean Paul <seanpaul@chromium.org>
Cc: Matt Roper <matthew.d.roper@intel.com>
Reviewed-by: Sean Paul <seanpaul@chromium.org>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>