This is required to get fbcon probing to work on new connectors,
callers should acquire the mode config lock before calling these.
Reviewed-by: Todd Previte <tprevite@gmail.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>
To implement hotplug detection in a race-free manner, drivers must call
drm_kms_helper_poll_init() before hotplug events can be triggered. Such
events can be triggered right after any of the encoders or connectors
are initialized. At the same time, if the drm_fb_helper_hotplug_event()
helper is used by a driver, then the poll helper requires some parts of
the FB helper to be initialized to prevent a crash.
At the same time, drm_fb_helper_init() requires information that is not
necessarily available at such an early stage (number of CRTCs and
connectors), so it cannot be used yet.
Add a new helper, drm_fb_helper_prepare(), that initializes the bare
minimum needed to allow drm_kms_helper_poll_init() to execute and any
subsequent hotplug events to be processed properly.
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Thierry Reding <treding@nvidia.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>
Some drivers need to be able to have a perfect race-free fbcon setup.
Current drivers only enable hotplug processing after the call to
drm_fb_helper_initial_config which leaves a tiny but important race.
This race is especially noticable on embedded platforms where the
driver itself enables the voltage for the hdmi output, since only then
will monitors (after a bit of delay, as usual) respond by asserting
the hpd pin.
Most of the infrastructure is already there with the split-out
drm_fb_helper_init. And drm_fb_helper_initial_config already has all
the required locking to handle concurrent hpd events since
commit 53f1904bce
Author: Daniel Vetter <daniel.vetter@ffwll.ch>
Date: Thu Mar 20 14:26:35 2014 +0100
drm/fb-helper: improve drm_fb_helper_initial_config locking
The only missing bit is making drm_fb_helper_hotplug_event save
against concurrent calls of drm_fb_helper_initial_config. The only
unprotected bit is the check for fb_helper->fb.
With that drivers can first initialize the fb helper, then enabel
hotplug processing and then set up the initial config all in a
completely race-free manner. Update kerneldoc and convert i915 as a
proof of concept.
Feature requested by Thierry since his tegra driver atm reliably boots
slowly enough to misses the hotplug event for an external hdmi screen,
but also reliably boots to quickly for the hpd pin to be asserted when
the fb helper calls into the hdmi ->detect function.
Cc: Thierry Reding <treding@nvidia.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Thierry Reding <treding@nvidia.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>
The following list empty check is unnecessary because we would still do nothing
real and return 'val' if my_list is empty.
if (list_empty(&my_list))
return val;
list_for_each_entry(pos, &my_list, member) {
...
}
return val;
This patch removes the unnecessary check in drm_fb_helper_debug_enter().
Signed-off-by: Liu Ying <Ying.Liu@freescale.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
The variable info->fix.type_aux is set to zero twice in the function
drm_fb_helper_fill_fix(). This patch removes one redundant.
Signed-off-by: Liu Ying <Ying.Liu@freescale.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
All drm_fb_helper_restore_fbdev_mode() call sites, save one, do the same
locking. Simplify this into drm_fb_helper_restore_fbdev_mode_unlocked().
Signed-off-by: Rob Clark <robdclark@gmail.com>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Dave Airlie <airlied@redhat.com>
For atomic, it will be quite necessary to not need to care so much
about locking order. And 'state' gives us a convenient place to stash a
ww_ctx for any sort of update that needs to grab multiple crtc locks.
Because we will want to eventually make locking even more fine grained
(giving locks to planes, connectors, etc), split out drm_modeset_lock
and drm_modeset_acquire_ctx to track acquired locks.
Atomic will use this to keep track of which locks have been acquired
in a transaction.
v1: original
v2: remove a few things not needed until atomic, for now
v3: update for v3 of connection_mutex patch..
v4: squash in docbook
v5: doc tweaks/fixes
Signed-off-by: Rob Clark <robdclark@gmail.com>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Dave Airlie <airlied@redhat.com>
Fix a few trivial typos in the framebuffer helper documentation.
Signed-off-by: Thierry Reding <treding@nvidia.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Commit 62ff94a549 "drm/crtc-helper: remove LOCKING from kerneldoc"
causes drm_helper_crtc_in_use() and drm_helper_encoder_in_use() to
complain loudly during a kernel panic or sysrq processing. This is
caused by nobody acquiring the modeset lock in these code paths.
This patch fixes this by trying to acquire the modeset lock for each
FB helper that's forced to kernel mode. If the lock can't be acquired,
it's likely that somebody else is performing a modeset. However, doing
another modeset concurrently might make things even worse, so the safe
option is to simply bail out in that case.
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Reviewed-by: David Herrmann <dh.herrmann@gmail.com>
Signed-off-by: Thierry Reding <treding@nvidia.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Currently drm_pick_cmdline_mode() doesn't care about the interlace
when the given mode line has no "i" suffix. That is, when there are
multiple entries for the same resolution, an interlace mode might be
picked up just depending on the assigned order, and there is no way to
exclude it.
This patch changes the logic for the mode selection, to prefer the
noninterlace mode unless the interlace mode is explicitly given.
When no matching mode is found, it still tries the interlace mode as
fallback.
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Dave Airlie <airlied@redhat.com>
Now that CRTC's have a primary plane, there's no need to track the
framebuffer in the CRTC. Replace all references to the CRTC fb with the
primary plane's fb.
This patch was generated by the Coccinelle semantic patching tool using
the following rules:
@@ struct drm_crtc C; @@
- (C).fb
+ C.primary->fb
@@ struct drm_crtc *C; @@
- (C)->fb
+ C->primary->fb
v3: Generate patch via coccinelle. Actual removal of crtc->fb has been
moved to a subsequent patch.
v2: Fixup several lingering crtc->fb instances that were missed in the
first patch iteration. [Rob Clark]
Signed-off-by: Matt Roper <matthew.d.roper@intel.com>
Reviewed-by: Rob Clark <robdclark@gmail.com>
The DRM core currently only tracks "overlay"-style planes. Start
refactoring the plane handling to allow other plane types (primary and
cursor) to also be placed on the DRM plane list.
v2: Add drm_for_each_legacy_plane() iterator to smooth transition
of drivers with plane loops.
Signed-off-by: Matt Roper <matthew.d.roper@intel.com>
Reviewed-by: Rob Clark <robdclark@gmail.com>
The locking in drm_fb_helper_initial_config is a bit troublesome for a
few reasons:
- We can't just wrap the entire function up into modeset locks since
the fbdev registration might call down into fbcon code, which then
through our ->set_par implementation needs to be able to grab all
modeset locks. So we'd have a neat deadlock.
- This implies though that all current callers don't hold any modeset
locks by necessity, so we have free reign to grab any modeset locks
we need to grab.
- The private state of the fbdev helper doesn't need any protection
through locks, since once we have the fbdev registered it is mostly
invariant or protected through the modeset locking in ->set_par and
other callbacks. We can fully rely on driver having non-racy setup
sequences here. For the initial config computation we actually may
not grab locks since drivers which provide their own magic sauce
(like i915) might need to grab locks themselves.
- We should grab locks though when we probe outputs. Currently there's
not much risk, but already now userspace could start poking at sysfs
files and so probe concurrently. I expect that in the future driver
init will be much more async, and since probing is really
time-consuming this is a prime candidate.
- We must not hold any crtc->mutex locks while calling probe functions
since those might need to lock a crtc for e.g. load detection. i915
is such a driver.
Also it's the probing calls which hit upon piles of new locking
asserts I've recently added in
commit 62ff94a549
Author: Daniel Vetter <daniel.vetter@ffwll.ch>
Date: Thu Jan 23 22:18:47 2014 +0100
drm/crtc-helper: remove LOCKING from kerneldoc
and
commit 6395138505
Author: Daniel Vetter <daniel.vetter@ffwll.ch>
Date: Thu Jan 23 15:14:15 2014 +0100
drm/doc: Repleace LOCKING kerneldoc sections in drm_modes.c
Hence the right fix is to grab the mode_config mutex, but only that
and only right around the probe calls.
It seems to be sufficient to shut up all the locking WARNINGs I see on
i915 and nouveau in drm_fb_helper_initial_config.
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Tested-by: Thierry Reding <treding@nvidia.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>
Merge straggling core drm patches.
* 'topic/core-stuff' of git://git.freedesktop.org/git/drm-intel:
drm: Fix use-after-free in the shadow-attache exit code
drm/fb-helper: Do the 'max_conn_count' zero check
drm: Check if the allocation has succeeded before dereferencing newmode
drm/fb-helper: Use drm_fb_helper_restore_fbdev_mode() in drm_fb_helper_set_par()
drm/edid: request HDMI underscan by default
Since we cannot make sure the 'max_conn_count' will always be none
zero from the users, and then if max_conn_count equals to zero, the
kcalloc() will return ZERO_SIZE_PTR, which equals to ((void *)16).
So this patch fix this with just doing the 'max_conn_count' zero check
in the front of drm_fb_helper_init().
Signed-off-by: Xiubo Li <Li.Xiubo@freescale.com>
CC: Jani Nikula <jani.nikula@linux.intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Use drm_fb_helper_restore_fbdev_mode() in drm_fb_helper_set_par() to
make sure extra planes get disabled whenever fbcon takes over.
Otherwise the code in drm_fb_helper_set_par() was already doing the
exact same thing as drm_fb_helper_restore_fbdev_mode(), so this doesn't
change the behaviour in any other way.
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Sometimes we want to disable all the screens on a system, because that
will allow the graphics card to be put into low-power states. The
problem is that, for example, while all screens are disabled, if we
get a hotplug interrupt, fbcon will decide to set a mode instead of
keeping everything disabled, which will remove us from our low power
states.
Let's assume that if there's a DRM master, it will be able to do
whatever is appropriate when we get the hotplug.
This problem can be reproduced by the runtime PM test program from
intel-gpu-tools: we disable all the screens so the graphics device can
be put into D3, then something triggers a hotplug interrupt, fbcon
sets a mode and breaks our test suite. The problem can be reproduced
more easily by the "i2c" subtest.
Other approaches considered for the problem:
- Return "false" if "bound == 0" and the caller of
drm_fb_helper_is_bound is a hotplug handler. This would break
the case where the machine boots with no outputs connected, then
the user plugs a monitor.
- Add a new IOCTL to force fbcon to not set modes. This would keep
all the current applications behaving the same, but adding a new
IOCTL is not always the greatest idea.
- Return false only if "dev->primary->master && bound == 0". This
was my first implementation, but Chris suggested we should do
the check irrespective of the "bound" variable.
Thanks to Daniel Vetter for the investigation, ideas and the
implementation of the hotplug alternative.
v2: - Do the check first, irrespective of "bound".
- Cc dri-devel
Cc: dri-devel@lists.freedesktop.org
Credits-to: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Paulo Zanoni <paulo.r.zanoni@intel.com>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Reviewed-by: David Herrmann <dh.herrmann@gmail.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>
I want to merge in the new Broadwell support as a late hw enabling
pull request. But since the internal branch was based upon our
drm-intel-nightly integration branch I need to resolve all the
oustanding conflicts in drm/i915 with a backmerge to make the 60+
patches apply properly.
We'll propably have some fun because Linus will come up with a
slightly different merge solution.
Conflicts:
drivers/gpu/drm/i915/i915_dma.c
drivers/gpu/drm/i915/i915_drv.c
drivers/gpu/drm/i915/intel_crt.c
drivers/gpu/drm/i915/intel_ddi.c
drivers/gpu/drm/i915/intel_display.c
drivers/gpu/drm/i915/intel_dp.c
drivers/gpu/drm/i915/intel_drv.h
All rather simple adjacent lines changed or partial backports from
-next to -fixes, with the exception of the thaw code in i915_dma.c.
That one needed a bit of shuffling to restore the intent.
Oh and the massive header file reordering in intel_drv.h is a bit
trouble. But not much.
v2: Also don't forget the fixup for the silent conflict that results
in compile fail ...
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
For drivers which might want to disable fbdev legacy support.
Select the new option in all drivers for now, so this shouldn't result
in any change. Drivers need some work anyway to make fbdev support
optional (if they have it implemented, that is), so the recommended
way to expose this is by adding per-driver options. At least as long
as most drivers don't support disabling the fbdev support.
v2: Update for new drm drivers msm and rcar-du. Note that Rob's msm
driver can already take advantage of this, which allows us to build
msm without any fbdev depencies in the kernel!
v3: Move the MODULE_* stuff from the fbdev helper file to
drm_crtc_helper.c.
Cc: David Herrmann <dh.herrmann@gmail.com>
Cc: Rob Clark <robdclark@gmail.com>
Reviewed-by: Rob Clark <robdclark@gmail.com>
Acked-by: Dave Airlie <airlied@linux.ie>
Reviewed-by: Chon Ming Lee <chon.ming.lee@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Sonika Jindal
Dave Airlie
Thierry Reding
Daniel Vetter
Liu Ying
Rob Clark
Jani Nikula
Takashi Iwai
Matt Roper
Xiubo Li
Ville Syrjälä
Jesse Barnes
Paulo Zanoni
Lespiau, Damien