It was only needed to protect the connector_list walking, see
commit 8c4ccc4ab6
Author: Daniel Vetter <daniel.vetter@ffwll.ch>
Date: Thu Jul 9 23:44:26 2015 +0200
drm/probe-helper: Grab mode_config.mutex in poll_init/enable
Unfortunately the commit message of that patch fails to mention that
the new locking check was for the connector_list.
But that requirement disappeared in
commit c36a3254f7
Author: Daniel Vetter <daniel.vetter@ffwll.ch>
Date: Thu Dec 15 16:58:43 2016 +0100
drm: Convert all helpers to drm_connector_list_iter
and so we can drop this again.
This fixes a locking inversion on nouveau, where the rpm code needs to
re-enable. But in other places the rpm_get() calls are nested within
the big modeset locks.
While at it, also improve the kerneldoc for these two functions a
notch.
v2: Update the kerneldoc even more to explain that these functions
can't be called concurrently, or bad things happen (Chris).
Cc: Dave Airlie <airlied@gmail.com>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Tested-by: Lyude <lyude@redhat.com>
Reviewed-by: Lyude <lyude@redhat.com>
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20170111090117.5134-1-daniel.vetter@ffwll.ch
PSR2 vsc revision number hb2( as per table 6-11)is updated to
4 or 5 based on Y cordinate and Colorimetry Format as below
04h = 3D stereo + PSR/PSR2 + Y-coordinate.
05h = -3D stereo- + PSR/PSR2 + Y-coordinate + Pixel Encoding/Colorimetry
Format indication. A DP Source device is allowed to indicate the pixel
encoding/colorimetry format to the DP Sink device with VSC SDP only when
the DP Sink device supports it (
i.e.,VSC_SDP_EXTENSION_FOR_COLORIMETRY_SUPPORTED bit in the
DPRX_FEATURE_ENUMERATION_LIST register (DPCD Address 02210h, bit 3;
is set to 1).
v2: (Jani)
- Change DP_PSR_Y_COORDINATE to DP_PSR2_SU_Y_COORDINATE_REQUIRED.
- Add DP_PSR2_SU_GRANULARITY_REQUIRED.
- Change DPRX_FEATURE_ENUMERATION_LIST to DP_DPRX.
- Add GTC_CAP and AV_SYNC_CAP, other bits in DPRX_FEATURE_ENUMERATION_LIST.
v3: (Jani)
- Add support for bits 7:4 and 1 as per DP v1.4 for
DPRX_FEATURE_ENUMERATION_LIST.
Cc: Rodrigo Vivi <rodrigo.vivi@intel.com>
Cc: Jim Bride <jim.bride@linux.intel.com>
Signed-off-by: Vathsala Nagaraju <vathsala.nagaraju@intel.com>
Signed-off-by: Patil Deepti <deepti.patil@intel.com>
Reviewed-by: Jani Nikula <jani.nikula@intel.com>
Signed-off-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1483356663-32668-2-git-send-email-vathsala.nagaraju@intel.com
Back to regular -misc pulls with reasonable sizes:
- dma_fence error clarification (Chris)
- drm_crtc_from_index helper (Shawn), pile more patches on the m-l to roll
this out to drivers
- mmu-less support for fbdev helpers from Benjamin
- piles of kerneldoc work
- some polish for crc support from Tomeu and Benjamin
- odd misc stuff all over
* tag 'drm-misc-next-2017-01-09' of git://anongit.freedesktop.org/git/drm-misc: (48 commits)
dma-fence: Introduce drm_fence_set_error() helper
dma-fence: Wrap querying the fence->status
dma-fence: Clear fence->status during dma_fence_init()
drm: fix compilations issues introduced by "drm: allow to use mmuless SoC"
drm: Change the return type of the unload hook to void
drm: add more document for drm_crtc_from_index()
drm: remove useless parameters from drm_pick_cmdline_mode function
drm: crc: Call wake_up_interruptible() each time there is a new CRC entry
drm: allow to use mmuless SoC
drm: compile drm_vm.c only when needed
fbmem: add a default get_fb_unmapped_area function
drm: crc: Wait for a frame before returning from open()
drm: Move locking into drm_debugfs_crtc_crc_add
drm/imx: imx-tve: Remove unused variable
Revert "drm: nouveau: fix build when LEDS_CLASS=m"
drm: Add kernel-doc for drm_crtc_commit_get/put
drm/atomic: Fix outdated comment.
drm: reference count event->completion
gpu: drm: mgag200: mgag200_main:- Handle error from pci_iomap
drm: Document deprecated load/unload hook
...
The integer returned by the unload hook is ignored by the drm core, so
let's make it void.
This patch was created using the following Coccinelle semantic script
(except for the declaration and comment in drm_drv.h):
Compile-tested only.
// <smpl>
@ get_name @
struct drm_driver drv;
identifier fn;
@@
drv.unload = fn;
@ replace_type @
identifier get_name.fn;
@@
- int
+ void
fn (...)
{
...
}
@ remove_return_param @
identifier get_name.fn;
@@
void fn (...)
{
<...
if (...)
return
- ...
;
...>
}
@ drop_final_return @
identifier get_name.fn;
@@
void fn (...)
{
...
- return 0;
}
// </smpl>
Suggested-by: Daniel Vetter <daniel.vetter@intel.com>
Signed-off-by: Gabriel Krisman Bertazi <krisman@collabora.co.uk>
Acked-by: Christian König <christian.koenig@amd.com>.
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/20170106175731.29196-1-krisman@collabora.co.uk
Some SoC without MMU have display driver where a drm/kms driver
could be implemented.
Before doing such kind of thing drm/kms must allow to use mmuless devices.
This patch propose to remove MMU configuration flag and add a cma helper
function to help implementing mmuless display driver
version 4:
- add documentation about drm_gem_cma_get_unmapped_area()
- stub it MMU case
Signed-off-by: Benjamin Gaignard <benjamin.gaignard@linaro.org>
[danvet: Use recommended struct member references in kernel-doc.]
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/1483521177-21794-4-git-send-email-benjamin.gaignard@linaro.org
Directly merge drm-misc into drm-intel since Dave is on vacation and
we need the various drm-misc patches (fb format rework, drm mm fixes,
selftest framework and others). Also pulled back -rc2 in first to
resync with drm-intel-fixes and make sure I can reuse the exact rerere
solutions from drm-tip for safety, and because I'm lazy.
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Backmerge Linux 4.10-rc2 to resync with our -fixes cherry-picks. I've
done the backmerge directly because Dave is on vacation.
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
When writing the generic nonblocking commit code I assumed that
through clever lifetime management I can assure that the completion
(stored in drm_crtc_commit) only gets freed after it is completed. And
that worked.
I also wanted to make nonblocking helpers resilient against driver
bugs, by having timeouts everywhere. And that worked too.
Unfortunately taking boths things together results in oopses :( Well,
at least sometimes: What seems to happen is that the drm event hangs
around forever stuck in limbo land. The nonblocking helpers eventually
time out, move on and release it. Now the bug I tested all this
against is drivers that just entirely fail to deliver the vblank
events like they should, and in those cases the event is simply
leaked. But what seems to happen, at least sometimes, on i915 is that
the event is set up correctly, but somohow the vblank fails to fire in
time. Which means the event isn't leaked, it's still there waiting for
eventually a vblank to fire. That tends to happen when re-enabling the
pipe, and then the trap springs and the kernel oopses.
The correct fix here is simply to refcount the crtc commit to make
sure that the event sticks around even for drivers which only
sometimes fail to deliver vblanks for some arbitrary reasons. Since
crtc commits are already refcounted that's easy to do.
References: https://bugs.freedesktop.org/show_bug.cgi?id=96781
Cc: Jim Rees <rees@umich.edu>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Cc: Jani Nikula <jani.nikula@linux.intel.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/20161221102331.31033-1-daniel.vetter@ffwll.ch
Insulate users from changes to the internal hole tracking within
struct drm_mm_node by using an accessor for hole_follows.
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
[danvet: resolve conflicts in i915_vma.c]
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Using mm->color_adjust makes the eviction scanner much tricker since we
don't know the actual neighbours of the target hole until after it is
created (after scanning is complete). To work out whether we need to
evict the neighbours because they impact upon the hole, we have to then
check the hole afterwards - requiring an extra step in the user of the
eviction scanner when they apply color_adjust.
v2: Massage kerneldoc.
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/20161222083641.2691-34-chris@chris-wilson.co.uk
The scan state occupies a large proportion of the struct drm_mm and is
rarely used and only contains temporary state. That makes it suitable to
moving to its struct and onto the stack of the callers.
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
[danvet: Fix up etnaviv to compile, was missing a BUG_ON.]
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
This was entirely automated, using the script by Al:
PATT='^[[:blank:]]*#[[:blank:]]*include[[:blank:]]*<asm/uaccess.h>'
sed -i -e "s!$PATT!#include <linux/uaccess.h>!" \
$(git grep -l "$PATT"|grep -v ^include/linux/uaccess.h)
to do the replacement at the end of the merge window.
Requested-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
- Modeset state needs mode_config->connection mutex, that covers
figuring out the encoder, and reading properties (since in the
atomic case those need to look at connector->state).
- Don't hold any locks for stuff that's invariant (i.e. possible
connectors).
- Same for connector lookup and unref, those don't need any locks.
- And finally the probe stuff is only protected by mode_config->mutex.
While at it updated the kerneldoc for these fields in drm_connector
and add docs explaining what's protected by which locks.
Reviewed-by: Sean Paul <seanpaul@chromium.org>
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20161213230814.19598-10-daniel.vetter@ffwll.ch
The requirements for connector_list locking are a bit tricky:
- We need to be able to jump over zombie conectors (i.e. with refcount
== 0, but not yet removed from the list). If instead we require that
there's no zombies on the list then the final kref_put must happen
under the list protection lock, which means that locking context
leaks all over the place. Not pretty - better to deal with zombies
and wrap the locking just around the list_del in the destructor.
- When we walk the list we must _not_ hold the connector list lock. We
walk the connector list at an absolutely massive amounts of places,
if all those places can't ever call drm_connector_unreference the
code would get unecessarily complicated.
- connector_list needs it own lock, again too many places that walk it
that we could reuse e.g. mode_config.mutex without resulting in
inversions.
- Lots of code uses these loops to look-up a connector, i.e. they want
to be able to call drm_connector_reference. But on the other hand we
want connectors to stay on that list until they're dead (i.e.
connector_list can't hold a full reference), which means despite the
"can't hold lock for the loop body" rule we need to make sure a
connector doesn't suddenly become a zombie.
At first Dave&I discussed various horror-show approaches using srcu,
but turns out it's fairly easy:
- For the loop body we always hold an additional reference to the
current connector. That means it can't zombify, and it also means
it'll stay on the list, which means we can use it as our iterator to
find the next connector.
- When we try to find the next connector we only have to jump over
zombies. To make sure we don't chase bad pointers that entire loop
is protected with the new connect_list_lock spinlock. And because we
know that we're starting out with a non-zombie (need to drop our
reference for the old connector only after we have our new one),
we're guranteed to still be on the connector_list and either find
the next non-zombie or complete the iteration.
- Only downside is that we need to make sure that the temporary
reference for the loop body doesn't leak. iter_get/put() functions +
lockdep make sure that's the case.
- To avoid a flag day the new iterator macro has an _iter postfix. We
can rename it back once all the users of the unsafe version are gone
(there's about 100 list walkers for the connector_list).
For now this patch only converts all the list walking in the core,
leaving helpers and drivers for later patches. The nice thing is that
we can now finally remove 2 FIXME comments from the
register/unregister functions.
v2:
- use irqsafe spinlocks, so that we can use this in drm_state_dump
too.
- nuke drm_modeset_lock_all from drm_connector_init, now entirely
cargo-culted nonsense.
v3:
- do {} while (!kref_get_unless_zero), makes for a tidier loop (Dave).
- pretty kerneldoc
- add EXPORT_SYMBOL, helpers&drivers are supposed to use this.
v4: Change lockdep annotations to only check whether we release the
iter fake lock again (i.e. make sure that iter_put is called), but
not check any locking dependecies itself. That seams to require a
recursive read lock in trylock mode.
Cc: Dave Airlie <airlied@gmail.com>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Sean Paul <seanpaul@chromium.org>
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20161213230814.19598-6-daniel.vetter@ffwll.ch
