The first time we install a mode, the vblank will be disabled for a pipe
and so drm_vblank_get() in drm_vblank_pre_modeset() will fail. As we
unconditionally call drm_vblank_put() afterwards, the vblank reference
counter becomes unbalanced.
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Acked-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: Dave Airlie <airlied@linux.ie>
In dc1336ff4f (set vblank enable flag correctly
across IRQ uninstall), we made sure drivers that uninstall their interrupt
handler set the vblank enabled flag correctly, so that when interrupts are
re-enabled, vblank interrupts & counts work as expected. However I missed the
last_vblank field: it needs to be updated as well, otherwise, at the next
drm_update_vblank_count we'll end up comparing a current count to a stale
one (the last one captured by the disable function), which may trigger the
wraparound handling, leading to a jumpy counter and hangs in drm_wait_vblank.
The jumpy counter can prevent the DRM_WAIT_ON from returning success if the
difference between the current count and the requested count is greater than
2^23, leading to timeouts or hangs, if the ioctl is restarted in a loop (as
is the case in libdrm < 2.4.4).
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Acked-by: Michel Dänzer <michel@daenzer.net>
Tested-by: Timo Aaltonen <tjaalton@cc.hut.fi>
Signed-off-by: Dave Airlie <airlied@redhat.com>
Schedule a vblank signal, kill the process, and we'll go walking over freed
memory. Given that no open-source userland exists using this, nor have I
ever heard of a consumer, just let this code die.
Signed-off-by: Eric Anholt <eric@anholt.net>
Requested-by: Linus Torvalds <torvalds@linux-foundation.org>
Acked-by: Dave Airlie <airlied@linux.ie>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
In the absence of kernel mode setting, many drivers disable IRQs across VT
switch. The core DRM vblank code is missing a check for this case however;
even after IRQ disable, the vblank code will still have the vblank_enabled
flag set, so unless we track the fact that they're disabled at IRQ uninstall
time, when we VT switch back in we won't actually re-enable them, which means
any apps waiting on vblank before the switch will hang.
This patch does that and also adds a sanity check to the wait condition to
look for the irq_enabled flag in general, as well as adding a wakeup to the
IRQ uninstall path.
Fixes fdo bug #18879 with compiz hangs at VT switch.
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: Eric Anholt <eric@anholt.net>
Signed-off-by: Dave Airlie <airlied@linux.ie>
Add mode setting support to the DRM layer.
This is a fairly big chunk of work that allows DRM drivers to provide
full output control and configuration capabilities to userspace. It was
motivated by several factors:
- the fb layer's APIs aren't suited for anything but simple
configurations
- coordination between the fb layer, DRM layer, and various userspace
drivers is poor to non-existent (radeonfb excepted)
- user level mode setting drivers makes displaying panic & oops
messages more difficult
- suspend/resume of graphics state is possible in many more
configurations with kernel level support
This commit just adds the core DRM part of the mode setting APIs.
Driver specific commits using these new structure and APIs will follow.
Co-authors: Jesse Barnes <jbarnes@virtuousgeek.org>, Jakob Bornecrantz <jakob@tungstengraphics.com>
Contributors: Alan Hourihane <alanh@tungstengraphics.com>, Maarten Maathuis <madman2003@gmail.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: Eric Anholt <eric@anholt.net>
Signed-off-by: Dave Airlie <airlied@redhat.com>
drm vblank initialization keeps track of the changes in driver-supplied
frame counts across vt switch and mode setting, but only if you let it by
not tearing down the drm vblank structure.
Signed-off-by: Keith Packard <keithp@keithp.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>
It's not used in any other drivers, and doesn't look like it will be from
drm.git master.
Signed-off-by: Eric Anholt <eric@anholt.net>
Signed-off-by: Dave Airlie <airlied@linux.ie>
If the failing paths were hit, the vblank IRQ would never get turned off
again.
Signed-off-by: Eric Anholt <eric@anholt.net>
Acked-by: Keith Packard <keithp@keithp.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>
Like the last patch but adds a macro to get at the irq value instead of
dereferencing pdev directly. Should make things easier for the BSD guys and
if we ever support non-PCI devices.
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: Dave Airlie <airlied@redhat.com>
Previously, drivers supporting vblank interrupt waits would run the interrupt
all the time, or all the time that any 3d client was running, preventing the
CPU from sleeping for long when the system was otherwise idle. Now, interrupts
are disabled any time that no client is waiting on a vblank event. The new
method uses vblank counters on the chipsets when the interrupts are turned
off, rather than counting interrupts, so that we can continue to present
accurate vblank numbers.
Co-author: Michel Dänzer <michel@tungstengraphics.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: Eric Anholt <eric@anholt.net>
Signed-off-by: Dave Airlie <airlied@redhat.com>
Previous attempts at interrupt mitigation had been foiled by i915_wait_irq's
failure to update the sarea seqno value when the status page indicated that
the seqno had already been passed. MSI support has been seen to cut CPU
costs by up to 40% in some workloads by avoiding other expensive interrupt
handlers for frequent graphics interrupts.
Signed-off-by: Eric Anholt <eric@anholt.net>
Signed-off-by: Dave Airlie <airlied@redhat.com>
If a specific tasklet shares data with irq context,
it needs to take a private irq-blocking spinlock within
the tasklet itself.
Signed-off-by: Dave Airlie <airlied@redhat.com>
With the coming of kernel based modesetting and the memory manager stuff,
the everything in one directory approach was getting very ugly and
starting to be unmanageable.
This restructures the drm along the lines of other kernel components.
It creates a drivers/gpu/drm directory and moves the hw drivers into
subdirectores. It moves the includes into an include/drm, and
sets up the unifdef for the userspace headers we should be exporting.
Signed-off-by: Dave Airlie <airlied@redhat.com>
Chris Wilson