It takes an unsigned value. This happens not to blow up on 64-bit
architectures, but it does on 32-bit, causing
drm_calc_vbltimestamp_from_scanoutpos() to calculate totally bogus
timestamps for vblank events. Which in turn causes e.g. gnome-shell to
hang after a DPMS off cycle with current xf86-video-ati Git.
[airlied: regression introduced in drm: use monotonic time in drm_calc_vbltimestamp_from_scanoutpos]
Cc: stable@vger.kernel.org
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=59339
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=59836
Tested-by: shui yangwei <yangweix.shui@intel.com>
Signed-off-by: Michel Dänzer <michel.daenzer@amd.com>
Reviewed-by: Imre Deak <imre.deak@intel.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>
When GPU acceleration is disabled, drm_vblank_cleanup() will free the
vblank-related data, such as vblank_refcount, vblank_inmodeset, etc.
But we found that drm_vblank_post_modeset() may be called after the
cleanup, which use vblank_refcount and vblank_inmodeset. And this will
cause a kernel panic.
Fix this by return immediately if dev->num_crtcs is zero. This is the
same thing that drm_vblank_pre_modeset() does.
Call trace of a drm_vblank_post_modeset() after drm_vblank_cleanup():
[ 62.628906] [<ffffffff804868d0>] drm_vblank_post_modeset+0x34/0xb4
[ 62.628906] [<ffffffff804c7008>] atombios_crtc_dpms+0xb4/0x174
[ 62.628906] [<ffffffff804c70e0>] atombios_crtc_commit+0x18/0x38
[ 62.628906] [<ffffffff8047f038>] drm_crtc_helper_set_mode+0x304/0x3cc
[ 62.628906] [<ffffffff8047f92c>] drm_crtc_helper_set_config+0x6d8/0x988
[ 62.628906] [<ffffffff8047dd40>] drm_fb_helper_set_par+0x94/0x104
[ 62.628906] [<ffffffff80439d14>] fbcon_init+0x424/0x57c
[ 62.628906] [<ffffffff8046a638>] visual_init+0xb8/0x118
[ 62.628906] [<ffffffff8046b9f8>] take_over_console+0x238/0x384
[ 62.628906] [<ffffffff80436df8>] fbcon_takeover+0x7c/0xdc
[ 62.628906] [<ffffffff8024fa20>] notifier_call_chain+0x44/0x94
[ 62.628906] [<ffffffff8024fcbc>] __blocking_notifier_call_chain+0x48/0x68
[ 62.628906] [<ffffffff8042d990>] register_framebuffer+0x228/0x260
[ 62.628906] [<ffffffff8047e010>] drm_fb_helper_single_fb_probe+0x260/0x314
[ 62.628906] [<ffffffff8047e2c4>] drm_fb_helper_initial_config+0x200/0x234
[ 62.628906] [<ffffffff804e5560>] radeon_fbdev_init+0xd4/0xf4
[ 62.628906] [<ffffffff804e0e08>] radeon_modeset_init+0x9bc/0xa18
[ 62.628906] [<ffffffff804bfc14>] radeon_driver_load_kms+0xdc/0x12c
[ 62.628906] [<ffffffff8048b548>] drm_get_pci_dev+0x148/0x238
[ 62.628906] [<ffffffff80423564>] local_pci_probe+0x5c/0xd0
[ 62.628906] [<ffffffff80241ac4>] work_for_cpu_fn+0x1c/0x30
[ 62.628906] [<ffffffff802427c8>] process_one_work+0x274/0x3bc
[ 62.628906] [<ffffffff80242934>] process_scheduled_works+0x24/0x44
[ 62.628906] [<ffffffff8024515c>] worker_thread+0x31c/0x3f4
[ 62.628906] [<ffffffff802497a8>] kthread+0x88/0x90
[ 62.628906] [<ffffffff80206794>] kernel_thread_helper+0x10/0x18
Signed-off-by: Huacai Chen <chenhc@lemote.com>
Signed-off-by: Binbin Zhou <zhoubb@lemote.com>
Cc: <stable@vger.kernel.org>
Reviewed-by: Michel Dänzer <michel.daenzer@amd.com>
Acked-by: Paul Menzel <paulepanter@users.sourceforge.net>
Signed-off-by: Dave Airlie <airlied@gmail.com>
Initialize e->pipe.. some drivers set this themselves, others do not.
Setting it in drm_send_vblank_event() should help ensure more consistent
behavior with the different drivers.
Signed-off-by: Rob Clark <robdclark@gmail.com>
It is a bit more precise to compute the total number of pixels first and
then divide, rather than multiplying the line pixel count by the
already-rounded line duration.
Signed-off-by: Daniel Kurtz <djkurtz@chromium.org>
Signed-off-by: Dave Airlie <airlied@redhat.com>
Drivers that register interrupt handlers without the DRM core helpers
don't initialize the .irq_enabled field and drm_dev_to_irq() may fail
when called on them. This shouldn't preclude them from implementing
the vblank IOCTL.
Signed-off-by: Thierry Reding <thierry.reding@avionic-design.de>
Signed-off-by: Dave Airlie <airlied@redhat.com>
Currently the only users of drm_vblank_off() are i915 and gma500,
neither of which holds the event_lock when calling this function.
Fix this by holding the event_lock while traversing the list.
Signed-off-by: Imre Deak <imre.deak@intel.com>
Signed-off-by: Inki Dae <inki.dae@samsung.com>
Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com>
When trying to obtain an accurate timestamp for the last vsync interrupt
in vblank_disable_and_save() we loop until the vsync counter after reading
the time stamp is identical to the one before.
In the case where no hardware timestamp can be obtained there is probably
no point in trying to make sure we remain within the same vsync during
the time we obtain the counter.
Furthermore we should make sure there's an 'emergency exit' so that we
don't end up in an endless loop when the driver get_vblank_timestamp()
function doesn't manage to return within the same vsync.
This may happen when this function prints out debugging information over
a slow (ie serial) line.
Signed-off-by: Egbert Eich <eich@suse.de>
Signed-off-by: Dave Airlie <airlied@redhat.com>
Jumps in the vblank and page flip event timestamps cause trouble for
clients, so we should avoid them. The timestamp we get currently with
gettimeofday can jump, so use instead monotonic timestamps.
For backward compatibility use a module flag to revert back to using
gettimeofday timestamps. Add also a DRM_CAP_TIMESTAMP_MONOTONIC flag
that is simply a read only version of the module flag, so that clients
can query this without depending on sysfs.
Signed-off-by: Imre Deak <imre.deak@intel.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>
For measuring duration we want to avoid that our start/end timestamps
jump, so use monotonic instead of real time for that.
Signed-off-by: Imre Deak <imre.deak@intel.com>
Reviewed-by: mario.kleiner
Signed-off-by: Dave Airlie <airlied@redhat.com>
A helper that drivers can use to send vblank event after a pageflip.
If the driver doesn't support proper vblank irq based time/seqn then
just pass -1 for the pipe # to get do_gettimestamp() behavior (since
there are a lot of drivers that don't use drm_vblank_count_and_time())
Also an internal send_vblank_event() helper for the various other code
paths within drm_irq that also need to send vblank events.
v1: original
v2: add back 'vblwait->reply.sequence = seq' which should not have
been deleted
v3: add WARN_ON() in case lock is not held and comments
v4: use WARN_ON_SMP() instead to fix issue with !SMP && !DEBUG_SPINLOCK
as pointed out by Marcin Slusarz
v5: update docbook
Signed-off-by: Rob Clark <rob@ti.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>
Pull drm merge (part 1) from Dave Airlie:
"So first of all my tree and uapi stuff has a conflict mess, its my
fault as the nouveau stuff didn't hit -next as were trying to rebase
regressions out of it before we merged.
Highlights:
- SH mobile modesetting driver and associated helpers
- some DRM core documentation
- i915 modesetting rework, haswell hdmi, haswell and vlv fixes, write
combined pte writing, ilk rc6 support,
- nouveau: major driver rework into a hw core driver, makes features
like SLI a lot saner to implement,
- psb: add eDP/DP support for Cedarview
- radeon: 2 layer page tables, async VM pte updates, better PLL
selection for > 2 screens, better ACPI interactions
The rest is general grab bag of fixes.
So why part 1? well I have the exynos pull req which came in a bit
late but was waiting for me to do something they shouldn't have and it
looks fairly safe, and David Howells has some more header cleanups
he'd like me to pull, that seem like a good idea, but I'd like to get
this merge out of the way so -next dosen't get blocked."
Tons of conflicts mostly due to silly include line changes, but mostly
mindless. A few other small semantic conflicts too, noted from Dave's
pre-merged branch.
* 'drm-next' of git://people.freedesktop.org/~airlied/linux: (447 commits)
drm/nv98/crypt: fix fuc build with latest envyas
drm/nouveau/devinit: fixup various issues with subdev ctor/init ordering
drm/nv41/vm: fix and enable use of "real" pciegart
drm/nv44/vm: fix and enable use of "real" pciegart
drm/nv04/dmaobj: fixup vm target handling in preparation for nv4x pcie
drm/nouveau: store supported dma mask in vmmgr
drm/nvc0/ibus: initial implementation of subdev
drm/nouveau/therm: add support for fan-control modes
drm/nouveau/hwmon: rename pwm0* to pmw1* to follow hwmon's rules
drm/nouveau/therm: calculate the pwm divisor on nv50+
drm/nouveau/fan: rewrite the fan tachometer driver to get more precision, faster
drm/nouveau/therm: move thermal-related functions to the therm subdev
drm/nouveau/bios: parse the pwm divisor from the perf table
drm/nouveau/therm: use the EXTDEV table to detect i2c monitoring devices
drm/nouveau/therm: rework thermal table parsing
drm/nouveau/gpio: expose the PWM/TOGGLE parameter found in the gpio vbios table
drm/nouveau: fix pm initialization order
drm/nouveau/bios: check that fixed tvdac gpio data is valid before using it
drm/nouveau: log channel debug/error messages from client object rather than drm client
drm/nouveau: have drm debugging macros build on top of core macros
...
Convert #include "..." to #include <path/...> in drivers/gpu/.
Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: Dave Airlie <airlied@redhat.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Acked-by: Dave Jones <davej@redhat.com>
Fixes the following sparse warning:
drivers/gpu/drm/drm_irq.c:1239:6:
warning: symbol 'drm_handle_vblank_events' was not declared. Should it be static?
Signed-off-by: Sachin Kamat <sachin.kamat@linaro.org>
Signed-off-by: Dave Airlie <airlied@redhat.com>
DRM_IOCTL_MODESET_CTL must only be used for UMS drivers. Make it a no-op
for KMS drivers.
Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Reviewed-by: Michel Dänzer <michel@daenzer.net>
Signed-off-by: Dave Airlie <airlied@gmail.com>
A race condition exists in drm_vblank_cleanup() if the vblank disable
timer callback runs after freeing the memory that its callback function
tries to access. Fix this by deleting the timer synchronously.
Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Reviewed-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>
remove declared but unused functions from drmP.h, fix the comments
where necessary. Also, remove drm_mem_info which is unused.
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
Signed-off-by: Dave Airlie <airlied@redhat.com>
commit 27641c3f (drm/vblank: Add support for precise vblank
timestamping) adds preempt_disable()/enable() around a spin locked
section with the comments:
* Disable preemption, so vblank_time_lock is held as short as
* possible, even under a kernel with PREEMPT_RT patches.
/* Disable preemption while holding vblank_time_lock. Do
* it explicitely to guard against PREEMPT_RT kernel.
Just that this has never been tested on a RT kernel which would have
granted that nonsense with a might_sleep() warning because
dev->vblank_time_lock is converted to a "sleeping" spinlock on RT.
So this is activly wrong on RT and superflous on mainline. Remove it.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Mario Kleiner <mario.kleiner@tuebingen.mpg.de>
Signed-off-by: Dave Airlie <airlied@redhat.com>
* 'drm-nouveau-fixes' of git://git.freedesktop.org/git/nouveau/linux-2.6:
drm/nouveau: Fix bandwidth calculation for DisplayPort
drm/nouveau: by default use low bpp framebuffer on low memory cards
drm/nv10: Change the BO size threshold determining the memory placement range.
drm/nvc0: enable acceleration for nvc1 by default
drm/nvc0/gr: fixup the mmio list register writes for 0xc1
drm/nvc1: hacky workaround to fix accel issues
drm/nvc0/gr: fix some bugs in grctx generation
drm/nvc0: enable acceleration on 0xc8 by default
drm/nvc0/vram: skip disabled PBFB subunits
drm/nv40/pm: fix issues on igp chipsets, which don't have memory
drm/nouveau: testing the wrong variable
drm/nvc0/vram: storage type 0xc3 is not compressed
drm/nv50: fix stability issue on NV86.
drm/nouveau: initialize chan->fence.lock before use
drm/nv50/vram: fix incorrect detection of bank count on newer chipsets
drm/nv50/gr: typo fix, how about we not reset fifo during graph init?
drm/nv50/bios: fixup mpll programming from the init table parser
drm/nouveau: fix oops if i2c bus not found in nouveau_i2c_identify()
drm: make sure drm_vblank_init() has been called before touching vbl_lock
during the review of the fix for locks problems in drm_wait_vblank,
a couple of false concerns were raised about how the drm_vblank_get
and drm_vblank_put are used in this function; it turned out that the
code is correct and that it cannot be simplified
add a few comments to explain non-obvious flows in the code,
to prevent "false alarms" in the future
v2: incorporate comments received from Daniel Vetter
Signed-off-by: Ilija Hadzic <ihadzic@research.bell-labs.com>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Dave Airlie <airlied@redhat.com>
The struct drm_driver has some function pointers for irq. They are
gpu specific and some functions aren't essential things. This can
prevents creation of unnecessary dummy function for irq.
Signed-off-by: Joonyoung Shim <jy0922.shim@samsung.com>
Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>
The registered irq should be unregistered by free_irq() if
irq_postinstall() returns the error after request_irq() is called
successfully.
[airlied: add vga switcheroo disable]
Signed-off-by: Joonyoung Shim <jy0922.shim@samsung.com>
Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>
* 'keithp/drm-intel-next' of /ssd/git/drm-next: (301 commits)
drm/i915: split PCH clock gating init
drm/i915: add Ivybridge clock gating init function
drm/i915: Update the location of the ringbuffers' HWS_PGA registers for IVB.
drm/i915: Add support for fence registers on Ivybridge.
drm/i915: Use existing function instead of open-coding fence reg clear.
drm/i915: split clock gating init into per-chipset functions
drm/i915: set IBX pch type explicitly
drm/i915: add Ivy Bridge PCI IDs and driver feature structs
drm/i915: add PantherPoint PCH ID
agp/intel: add Ivy Bridge support
drm/i915: ring support for Ivy Bridge
drm/i915: page flip support for Ivy Bridge
drm/i915: interrupt & vblank support for Ivy Bridge
drm/i915: treat Ivy Bridge watermarks like Sandy Bridge
drm/i915: manual FDI training for Ivy Bridge
drm/i915: add swizzle/tiling support for Ivy Bridge
drm/i915: Ivy Bridge has split display and pipe control
drm/i915: add IS_IVYBRIDGE macro for checks
drm/i915: add IS_GEN7 macro to cover Ivy Bridge and later
drm/i915: split enable/disable vblank code into chipset specific functions
...
This is the least-bad behaviour. It means that we signal the
vblank event before it actually happens, but since we're disabling
vblanks there's no guarantee that it will *ever* happen otherwise.
This prevents GL applications which use WaitMSC from hanging
indefinitely.
Signed-off-by: Christopher James Halse Rogers <christopher.halse.rogers@canonical.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>
Add __attribute__((format (printf, 4, 5))) to drm_ut_debug_printk
and fix fallout.
Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>
Below is a patch against drm-next branch of 2.6.38-rc8+ kernel that adds
the capability to wait on vblank events for CRTCs that are greater than 1
and thus cannot be represented with primary/secondary flags in the legacy
interface. It was discussed on the dri-devel list in these two threads:
http://lists.freedesktop.org/archives/dri-devel/2011-March/009009.htmlhttp://lists.freedesktop.org/archives/dri-devel/2011-March/009025.html
This patch extends the interface to drm_wait_vblank ioctl so that crtc>1
can be represented. It also adds a new capability to drm_getcap ioctl so
that the user space can check whether the new interface to drm_wait_vblank
is supported (and fall back to the legacy interface if not)
Signed-off-by: Ilija Hadzic <ihadzic@research.bell-labs.com>
Reviewed-by: Mario Kleiner <mario.kleiner at tuebingen.mpg.de>
Acked-by: Mario Kleiner <mario.kleiner at tuebingen.mpg.de>
Reviewed-by: Alex Deucher <alexdeucher@gmail.com>
Tested-by: Alex Deucher <alexdeucher@gmail.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>
* 'intel/drm-intel-next' of ../drm-next: (755 commits)
drm/i915: Only wait on a pending flip if we intend to write to the buffer
drm/i915/dp: Sanity check eDP existence
drm/i915: Rebind the buffer if its alignment constraints changes with tiling
drm/i915: Disable GPU semaphores by default
drm/i915: Do not overflow the MMADDR write FIFO
Revert "drm/i915: fix corruptions on i8xx due to relaxed fencing"
drm/i915: Don't save/restore hardware status page address register
drm/i915: don't store the reg value for HWS_PGA
drm/i915: fix memory corruption with GM965 and >4GB RAM
Linux 2.6.38-rc7
Revert "TPM: Long default timeout fix"
drm/i915: Re-enable GPU semaphores for SandyBridge mobile
drm/i915: Replace vblank PM QoS with "Interrupt-Based AGPBUSY#"
Revert "drm/i915: Use PM QoS to prevent C-State starvation of gen3 GPU"
drm/i915: Allow relocation deltas outside of target bo
drm/i915: Silence an innocuous compiler warning for an unused variable
fs/block_dev.c: fix new kernel-doc warning
ACPI: Fix build for CONFIG_NET unset
mm: <asm-generic/pgtable.h> must include <linux/mm_types.h>
x86: Use u32 instead of long to set reset vector back to 0
...
Conflicts:
drivers/gpu/drm/i915/i915_gem.c
Testing showed the current code can already handle doublescan
video modes just fine. A trivial tweak makes it work for interlaced
scanout as well.
Tested and shown to be precise on Radeon rv530, r600 and
Intel 945-GME.
Signed-off-by: Mario Kleiner <mario.kleiner@tuebingen.mpg.de>
Signed-off-by: Dave Airlie <airlied@redhat.com>
Documentation/atomic_ops.txt tells us that there are memory
barriers optimized for atomic_inc and other atomic_t ops.
Use these instead of smp_wmb(), and also to make the required
memory barriers around vblank counter increments more explicit.
Signed-off-by: Mario Kleiner <mario.kleiner@tuebingen.mpg.de>
Signed-off-by: Dave Airlie <airlied@redhat.com>
Use of abs() wrongly wrapped diff_ns to 32 bit, which gives a 1/4000
probability of a missed vblank increment at each vblank irq reenable
if the kms driver doesn't support high precision vblank timestamping.
Not a big deal in practice, but let's make it nice.
Signed-off-by: Mario Kleiner <mario.kleiner@tuebingen.mpg.de>
Signed-off-by: Dave Airlie <airlied@redhat.com>
This abstracts the pci/platform interface out a step further,
we can go further but this is far enough for now to allow USB
to be plugged in.
The drivers now just call the init code directly for their
device type.
Signed-off-by: Dave Airlie <airlied@redhat.com>
Hugh Dickins found that characters in xterm were going missing and oft
delayed. Being the curious type, he managed to associate this with the
new high-precision vblank patches; disabling these he found, restored
the orderliness of his characters.
The oddness begins when one realised that Hugh was not using vblanks at
all on his system (fvwm and some xterms). Instead, all he had to go on
were warning of a pipe underrun, curiously enough at around 60Hz. He
poked and found that in addition to the underrun warning, the hardware
was flagging the start of a new frame, a vblank, which in turn was
kicking off the pending vblank processing code.
There is little we can do for the underruns on Hugh's machine, a
Crestline [965GM], which must have its FIFO watermarks set to 8.
However, we do not need to process the vblank if we know that they are
disabled...
Reported-by: Hugh Dickins <hughd@google.com>
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
* 'intel/drm-intel-next' of /ssd/git/drm-next: (771 commits)
drm/i915: Undo "Uncouple render/power ctx before suspending"
drm/i915: Allow the application to choose the constant addressing mode
drm/i915: dynamic render p-state support for Sandy Bridge
drm/i915: Enable EI mode for RCx decision making on Sandybridge
drm/i915/sdvo: Border and stall select became test bits in gen5
drm/i915: Add Guess-o-matic for pageflip timestamping.
drm/i915: Add support for precise vblank timestamping (v2)
drm/i915: Add frame buffer compression on Sandybridge
drm/i915: Add self-refresh support on Sandybridge
drm/i915: Wait for vblank before unpinning old fb
Revert "drm/i915: Avoid using PIPE_CONTROL on Ironlake"
drm/i915: Pass clock limits down to PLL matcher
drm/i915: Poll for seqno completion if IRQ is disabled
drm/i915/ringbuffer: Make IRQ refcnting atomic
agp/intel: Fix missed cached memory flags setting in i965_write_entry()
drm/i915/sdvo: Only use the SDVO pin if it is in the valid range
drm/i915: Enable RC6 autodownclocking on Sandybridge
drm/i915: Terminate the FORCE WAKE after we have finished reading
drm/i915/gtt: Clear the cachelines upon resume
drm/i915: Restore GTT mapping first upon resume
...
This patch tries to make sure that the vbl.reply.sequence
vblank count for a queued or emitted vblank event always
corresponds to the true vblank count of queueing/emission, so
the ddx can rely on the returned target_msc for consistency
checks and implementation of swap_intervals in glXSwapBuffers().
Without this there is a small race-condition between the
userspace ddx queueing a vblank event and the vblank
counter incrementing before the event gets queued in
the kernel.
Signed-off-by: Mario Kleiner <mario.kleiner@tuebingen.mpg.de>
Acked-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: Dave Airlie <airlied@redhat.com>
The "e" pointer is either NULL or freed when we call
drm_vblank_put(dev, e->pipe) on the error path. Just pass the "pipe"
variable directly instead.
I changed another caller to use "pipe" as well for consistency.
Signed-off-by: Dan Carpenter <error27@gmail.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Kristian Høgsberg <krh@bitplanet.net>
Acked-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: Dave Airlie <airlied@redhat.com>
The DRI2 swap & sync implementation needs precise
vblank counts and precise timestamps corresponding
to those vblank counts. For conformance to the OpenML
OML_sync_control extension specification the DRM
timestamp associated with a vblank count should
correspond to the start of video scanout of the first
scanline of the video frame following the vblank
interval for that vblank count.
Therefore we need to carry around precise timestamps
for vblanks. Currently the DRM and KMS drivers generate
timestamps ad-hoc via do_gettimeofday() in some
places. The resulting timestamps are sometimes not
very precise due to interrupt handling delays, they
don't conform to OML_sync_control and some are wrong,
as they aren't taken synchronized to the vblank.
This patch implements support inside the drm core
for precise and robust timestamping. It consists
of the following interrelated pieces.
1. Vblank timestamp caching:
A per-crtc ringbuffer stores the most recent vblank
timestamps corresponding to vblank counts.
The ringbuffer can be read out lock-free via the
accessor function:
struct timeval timestamp;
vblankcount = drm_vblank_count_and_time(dev, crtcid, ×tamp).
The function returns the current vblank count and
the corresponding timestamp for start of video
scanout following the vblank interval. It can be
used anywhere between enclosing drm_vblank_get(dev, crtcid)
and drm_vblank_put(dev,crtcid) statements. It is used
inside the drmWaitVblank ioctl and in the vblank event
queueing and handling. It should be used by kms drivers for
timestamping of bufferswap completion.
The timestamp ringbuffer is reinitialized each time
vblank irq's get reenabled in drm_vblank_get()/
drm_update_vblank_count(). It is invalidated when
vblank irq's get disabled.
The ringbuffer is updated inside drm_handle_vblank()
at each vblank irq.
2. Calculation of precise vblank timestamps:
drm_get_last_vbltimestamp() is used to compute the
timestamp for the end of the most recent vblank (if
inside active scanout), or the expected end of the
current vblank interval (if called inside a vblank
interval). The function calls into a new optional kms
driver entry point dev->driver->get_vblank_timestamp()
which is supposed to provide the precise timestamp.
If a kms driver doesn't implement the entry point or
if the call fails, a simple do_gettimeofday() timestamp
is returned as crude approximation of the true vblank time.
A new drm module parameter drm.timestamp_precision_usec
allows to disable high precision timestamps (if set to
zero) or to specify the maximum acceptable error in
the timestamps in microseconds.
Kms drivers could implement their get_vblank_timestamp()
function in a gpu specific way, as long as returned
timestamps conform to OML_sync_control, e.g., by use
of gpu specific hardware timestamps.
Optionally, kms drivers can simply wrap and use the new
utility function drm_calc_vbltimestamp_from_scanoutpos().
This function calls a new optional kms driver function
dev->driver->get_scanout_position() which returns the
current horizontal and vertical video scanout position
of the crtc. The scanout position together with the
drm_display_timing of the current video mode is used
to calculate elapsed time relative to start of active scanout
for the current video frame. This elapsed time is subtracted
from the current do_gettimeofday() time to get the timestamp
corresponding to start of video scanout. Currently
non-interlaced, non-doublescan video modes, with or
without panel scaling are handled correctly. Interlaced/
doublescan modes are tbd in a future patch.
3. Filtering of redundant vblank irq's and removal of
some race-conditions in the vblank irq enable/disable path:
Some gpu's (e.g., Radeon R500/R600) send spurious vblank
irq's outside the vblank if vblank irq's get reenabled.
These get detected by use of the vblank timestamps and
filtered out to avoid miscounting of vblanks.
Some race-conditions between the vblank irq enable/disable
functions, the vblank irq handler and the gpu itself (updating
its hardware vblank counter in the "wrong" moment) are
fixed inside vblank_disable_and_save() and
drm_update_vblank_count() by use of the vblank timestamps and
a new spinlock dev->vblank_time_lock.
The time until vblank irq disable is now configurable via
a new drm module parameter drm.vblankoffdelay to allow
experimentation with timeouts that are much shorter than
the current 5 seconds and should allow longer vblank off
periods for better power savings.
Followup patches will use these new functions to
implement precise timestamping for the intel and radeon
kms drivers.
Signed-off-by: Mario Kleiner <mario.kleiner@tuebingen.mpg.de>
Signed-off-by: Dave Airlie <airlied@redhat.com>
Allows us to track each process that requests and completes events.
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: Dave Airlie <airlied@redhat.com>
Emit a trace point for vblank events. This can be helpful for mapping
drawing activity against the vblank frequency and period.
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: Dave Airlie <airlied@redhat.com>
Allow platform devices without PCI resources to be DRM devices.
[airlied: fixup warnings with dev pointers]
Signed-off-by: Jordan Crouse <jcrouse@codeaurora.org>
Signed-off-by: Dave Airlie <airlied@redhat.com>
* 'drm-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/airlied/drm-2.6:
drm/radeon: Fix sparc regression in r300_scratch()
drm: make sure vblank interrupts are disabled at DPMS time
drm/radeon/kms/evergreen: No EnableYUV table
drm/radeon: 9800 SE has only one quadpipe
drm/radeon/kms: don't print error for legal crtcs.
drm/radeon/kms/evergreen: fix LUT setup
When we call drm_vblank_off() at DPMS off time (to wake any clients so
they don't hang) we need to make sure interrupts are actually disabled.
If drm_vblank_off() gets called before the vblank usage timer expires,
it'll prevent the timer from disabling interrupts since it also clears
the vblank_enabled flag for the pipe.
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: Dave Airlie <airlied@redhat.com>
percpu.h is included by sched.h and module.h and thus ends up being
included when building most .c files. percpu.h includes slab.h which
in turn includes gfp.h making everything defined by the two files
universally available and complicating inclusion dependencies.
percpu.h -> slab.h dependency is about to be removed. Prepare for
this change by updating users of gfp and slab facilities include those
headers directly instead of assuming availability. As this conversion
needs to touch large number of source files, the following script is
used as the basis of conversion.
http://userweb.kernel.org/~tj/misc/slabh-sweep.py
The script does the followings.
* Scan files for gfp and slab usages and update includes such that
only the necessary includes are there. ie. if only gfp is used,
gfp.h, if slab is used, slab.h.
* When the script inserts a new include, it looks at the include
blocks and try to put the new include such that its order conforms
to its surrounding. It's put in the include block which contains
core kernel includes, in the same order that the rest are ordered -
alphabetical, Christmas tree, rev-Xmas-tree or at the end if there
doesn't seem to be any matching order.
* If the script can't find a place to put a new include (mostly
because the file doesn't have fitting include block), it prints out
an error message indicating which .h file needs to be added to the
file.
The conversion was done in the following steps.
1. The initial automatic conversion of all .c files updated slightly
over 4000 files, deleting around 700 includes and adding ~480 gfp.h
and ~3000 slab.h inclusions. The script emitted errors for ~400
files.
2. Each error was manually checked. Some didn't need the inclusion,
some needed manual addition while adding it to implementation .h or
embedding .c file was more appropriate for others. This step added
inclusions to around 150 files.
3. The script was run again and the output was compared to the edits
from #2 to make sure no file was left behind.
4. Several build tests were done and a couple of problems were fixed.
e.g. lib/decompress_*.c used malloc/free() wrappers around slab
APIs requiring slab.h to be added manually.
5. The script was run on all .h files but without automatically
editing them as sprinkling gfp.h and slab.h inclusions around .h
files could easily lead to inclusion dependency hell. Most gfp.h
inclusion directives were ignored as stuff from gfp.h was usually
wildly available and often used in preprocessor macros. Each
slab.h inclusion directive was examined and added manually as
necessary.
6. percpu.h was updated not to include slab.h.
7. Build test were done on the following configurations and failures
were fixed. CONFIG_GCOV_KERNEL was turned off for all tests (as my
distributed build env didn't work with gcov compiles) and a few
more options had to be turned off depending on archs to make things
build (like ipr on powerpc/64 which failed due to missing writeq).
* x86 and x86_64 UP and SMP allmodconfig and a custom test config.
* powerpc and powerpc64 SMP allmodconfig
* sparc and sparc64 SMP allmodconfig
* ia64 SMP allmodconfig
* s390 SMP allmodconfig
* alpha SMP allmodconfig
* um on x86_64 SMP allmodconfig
8. percpu.h modifications were reverted so that it could be applied as
a separate patch and serve as bisection point.
Given the fact that I had only a couple of failures from tests on step
6, I'm fairly confident about the coverage of this conversion patch.
If there is a breakage, it's likely to be something in one of the arch
headers which should be easily discoverable easily on most builds of
the specific arch.
Signed-off-by: Tejun Heo <tj@kernel.org>
Guess-its-ok-by: Christoph Lameter <cl@linux-foundation.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>
In some case vblank might not be initialized and we shouldn't
try to use associated function. This patch make sure this is
the case. It also export drm_vblank_cleanup so driver can cleanup
vblank if for any reason IRQ/MSI is not working.
Signed-off-by: Jerome Glisse <jglisse@redhat.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>
