Commit graph

558 commits

Author SHA1 Message Date
Eric Anholt
f0217c42c9 drm/i915: Fix DDC on some systems by clearing BIOS GMBUS setup.
This is a sync of a fix I made in the old UMS code.  If the BIOS uses
the GMBUS and doesn't clear that setup, then our bit-banging I2C can
fail, leading to monitors not being detected.

Signed-off-by: Eric Anholt <eric@anholt.net>
2009-12-01 11:56:30 -08:00
Zhao Yakui
d09c23de9f drm/i915: Add 30ms delay to make SDVO TV detection reliable.
Without this, on some boots the TV wouldn't be detected.  Testing
showed 15ms to be insufficient.

https://bugs.freedesktop.org/show_bug.cgi?id=24290
https://bugs.freedesktop.org/show_bug.cgi?id=20785

Signed-off-by: Zhao Yakui <yakui.zhao@intel.com>
Tested-by: Yan Seiner <yan@seiner.com>
Signed-off-by: Eric Anholt <eric@anholt.net>
2009-12-01 10:33:12 -08:00
Li Peng
778c902640 drm/i915: Fix sync to vblank when VGA output is turned off
In current vblank-wait implementation, if we turn off VGA output,
drm_wait_vblank will still wait on the disabled pipe until timeout,
because vblank on the pipe is assumed be enabled. This would cause
slow system response on some system such as moblin.

This patch resolve the issue by adding a drm helper function
drm_vblank_off which explicitly clear vblank_enabled[crtc], wake up
any waiting queue and save last vblank counter before turning off
crtc. It also slightly change drm_vblank_get to ensure that we will
will return immediately if trying to wait on a disabled pipe.

Signed-off-by: Li Peng <peng.li@intel.com>
Reviewed-by: Jesse Barnes <jbarnes@virtuousgeek.org>
[anholt: hand-applied for conflicts with overlay changes]
Signed-off-by: Eric Anholt <eric@anholt.net>
2009-12-01 10:27:40 -08:00
Adam Jackson
27dfaf4f58 drm/i915: disable the interrupt hotplug for integrated TV output
Otherwise, I'd get stuck in a loop where (afaict) output scan would
trigger a TV interrupt, which would trigger a scan, etc.  TV load
detection not being the fastest thing in the world, X would process
requests very slowly.

https://bugs.freedesktop.org/show_bug.cgi?id=24404

Signed-off-by: Adam Jackson <ajax@redhat.com>
Acked-by: Zhao Yakui <yakui.zhao@intel.com>
Signed-off-by: Eric Anholt <eric@anholt.net>
2009-12-01 09:49:36 -08:00
Chris Wilson
28cf798f5a drm/i915: Don't update the render-clock for every bo.
Only update the render-clock on transition from busy to idle and vice
versa, or else we burn a significant percentage of the cpu just rewriting
the register -- not quite as power-friendly as intended ;-)

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Jesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: Eric Anholt <eric@anholt.net>
2009-12-01 09:42:16 -08:00
Adam Jackson
38b3037ee4 drm/i915: Fix LVDS presence check
Assume that either the presence of an LVDS entry in the VBT or an ACPI
lid device indicates an LVDS device.  ACPI lid alone is not sufficient.

Signed-off-by: Adam Jackson <ajax@redhat.com>
Signed-off-by: Eric Anholt <eric@anholt.net>
2009-12-01 09:28:58 -08:00
Eric Anholt
05dd8f973f drm/i915: Fix warning introduced with the page flipping ioctl.
Signed-off-by: Eric Anholt <eric@anholt.net>
2009-12-01 09:25:23 -08:00
Jesse Barnes
e9560f7cb2 drm/i915: add GETPARAM request for page flipping
Add a GETPARAM request for checking if page flipping is supported.
Useful for the 2D driver to enable the flipping path.

Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: Eric Anholt <eric@anholt.net>
2009-12-01 09:19:07 -08:00
Kristian Høgsberg
6b95a207c1 drm/i915: Add intel implementation of the pageflip ioctl
Acked-by: Jakob Bornecrantz <jakob@vmware.com>
Acked-by: Thomas Hellström <thomas@shipmail.org>
Review-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Jesse "Orange Smoothie" Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: Kristian Høgsberg <krh@bitplanet.net>
Signed-off-by: Eric Anholt <eric@anholt.net>
2009-12-01 09:10:35 -08:00
Zhenyu Wang
103a196f42 drm/i915: PineView only has LVDS and CRT ports
PineView only has 2 ports for LVDS and CRT. Don't enable other
ports for it.

Cc: Shaohua Li <shaohua.li@intel.com>
Signed-off-by: Zhenyu Wang <zhenyuw@linux.intel.com>
Signed-off-by: Eric Anholt <eric@anholt.net>
2009-12-01 09:00:04 -08:00
Zhao Yakui
c35614380d drm/i915: Don't set up the TV port if it isn't in the BIOS table.
Signed-off-by: Zhao Yakui <yakui.zhao@intel.com>
Signed-off-by: Eric Anholt <eric@anholt.net>
2009-11-30 16:54:42 -08:00
Zhao Yakui
7cf4f69d3f drm/i915: Don't set up the LVDS if it isn't in the BIOS device table.
We not only check the device type, but also check the addin_offset. If the
addin_offset is zero, it won't be initialized.

Signed-off-by: Zhao Yakui <yakui.zhao@intel.com>
Reviewed-by: Adam Jackson <ajax@redhat.com>
Signed-off-by: Eric Anholt <eric@anholt.net>
[anholt: hand-applied due to conflicts]
2009-11-30 16:54:35 -08:00
Zhao Yakui
ae266c98f5 drm/i915: Don't set up DP ports that aren't in the BIOS device table.
Use the child device array to decide whether the given DP output should be
initialized. If the given DP port can't be found in child device array,
it is not present and won't be initialized.

Signed-off-by: Zhao Yakui <yakui.zhao@intel.com>
Signed-off-by: Eric Anholt <eric@anholt.net>
2009-11-30 16:42:56 -08:00
Zhao Yakui
fc81665523 drm/i915: Don't set up HDMI ports that aren't in the BIOS device table.
Use the child device array to decide whether the given HDMI output should be
initialized. If the given HDMI port can't be found in child device array,
it is not present and won't be initialized.

Signed-off-by: Zhao Yakui <yakui.zhao@intel.com>
Signed-off-by: Eric Anholt <eric@anholt.net>
2009-11-30 16:41:48 -08:00
Zhao Yakui
6363ee6f49 drm/i915: parse child device from VBT
On some laptops there is no HDMI/DP. But the xrandr still reports
several disconnected HDMI/display ports. In such case the user will be
confused.
 >DVI1 disconnected (normal left inverted right x axis y axis)
 >DP1 disconnected (normal left inverted right x axis y axis)
 >DVI2 disconnected (normal left inverted right x axis y axis)
 >DP2 disconnected (normal left inverted right x axis y axis)
 >DP3 disconnected (normal left inverted right x axis y axis)

This patch set is to use the child device parsed in VBT to decide whether
the HDMI/DP/LVDS/TV should be initialized.

Parse the child device from VBT.

The device class type is also added for LFP, TV, HDMI, DP output.

https://bugs.freedesktop.org/show_bug.cgi?id=22785

Signed-off-by: Zhao Yakui <yakui.zhao@intel.com>
Reviewed-by: Adam Jackson <ajax@redhat.com>
Signed-off-by: Eric Anholt <eric@anholt.net>
2009-11-30 16:36:53 -08:00
Kristian Høgsberg
c1b5dea097 drm/i915: Disable pwrctx before unpin and free
Otherwise the chip may scribble over free memory.

Signed-off-by: Kristian Høgsberg <krh@bitplanet.net>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: Eric Anholt <eric@anholt.net>
2009-11-30 16:27:23 -08:00
Kristian Høgsberg
69341a5e01 drm/i915: Hold struct_mutex while unreffing pwrctx object
This also extends the mutex to cover fbc disabling, which is safe.

Signed-off-by: Kristian Høgsberg <krh@bitplanet.net>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: Eric Anholt <eric@anholt.net>
2009-11-30 16:27:07 -08:00
Kristian Høgsberg
33db679b4e drm/i915: Unregister i915_wedged debugfs entry using the right key
Signed-off-by: Kristian Høgsberg <krh@bitplanet.net>
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: Eric Anholt <eric@anholt.net>
2009-11-30 16:24:23 -08:00
Shaohua Li
29874f44fb drm/i915: fix gpio register detection logic for BIOS without VBT
if no VBT is present, crt_ddc_bus will be left at 0, and cause us
to use that for the GPIO register offset. That's never a valid register
offset, so let the "undefined" value be 0 instead of -1.

Signed-off-by: Shaohua Li <shaohua.li@intel.com>
Signed-off-by: Zhao Yakui <yakui.zhao@intel.com>
Signed-off-by: Eric Anholt <eric@anholt.net>
[anholt: clarified the commit message a bit]
2009-11-30 16:10:56 -08:00
Chris Wilson
d271817bae drm/i915: Avoid NULL dereference with component_only tv_modes
In commit d2d9f2324, the guard for a valid video mode was removed. This
caused the regression:

  kernel crash during kms graphic boot on Intel GM4500 platform
  https://bugzilla.redhat.com/show_bug.cgi?id=540218

This patches changes the logic slightly not to rely on a coupled
variable, but to just check whether the video_modes is valid before
dereferencing.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: David Woodhouse <dwmw2@infradead.org>
Cc: Zhenyu Wang <zhenyu.z.wang@intel.com>
[ickle: Actually reference the correct bug report]
Acked-by: Zhenyu Wang <zhenyuw@linux.intel.com>
Signed-off-by: Eric Anholt <eric@anholt.net>
2009-11-30 15:16:32 -08:00
Daniel Vetter
9bedb9743f drm/i915: fixup interrupted overlay switch off calls
When switching to interruptible sleeps in the overlay code, I've
forgotten to recover from interruptions at one site.  This
resulted in the overlay still running when it should have been
switched off. This in turn caused a hang on resume because it
tried to disable the (not-running) overlay in preparation for the
resume modeset.

Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=24980
Tested-by: maximlevitsky@gmail.com

Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Eric Anholt <eric@anholt.net>
2009-11-30 09:50:57 -08:00
Daniel Vetter
12ca45fea9 drm/i915: overlay: extract some duplicated code
I've suspected some bug there wrt to suspend, but that was not
the case. Clean up the code anyway.

Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Eric Anholt <eric@anholt.net>
2009-11-30 09:44:23 -08:00
Shaohua Li
2644487781 drm/i915: remove Pineview EOS protection support
HW guys have an evaluation about the impact about EOS, and say the impact
is quite small, so they have removed EOS detection support. This patch
removes EOS feature.

revert commit 0430296558
directly reverting it gives a hunk error, so please use this one.

Signed-off-by: Shaohua Li <shaohua.li@intel.com>
Signed-off-by: Eric Anholt <eric@anholt.net>
[anholt: fixed up commit message for update that the feature's really gone]
2009-11-30 09:42:12 -08:00
Shaohua Li
311089d3d3 drm/i915: use msleep for intel_wait_for_vblank
20ms delay is quite big and the routine isn't called in atomic context.
better use msleep to let other tasks run. This can reduce cpu time used
by Xorg, so potentially boost boot.

Signed-off-by: Shaohua Li <shaohua.li@intel.com>
Signed-off-by: Eric Anholt <eric@anholt.net>
2009-11-30 09:39:57 -08:00
Shaohua Li
1991bdfaf5 drm/i915: handle failure path correctly for lvds
In failure path, make sure encoder is cleaned up, otherwise there
is a kernel oops.

Signed-off-by: Shaohua Li <shaohua.li@intel.com>
Signed-off-by: Eric Anholt <eric@anholt.net>
2009-11-25 13:45:55 -08:00
Zhenyu Wang
1b3c7a47f9 drm/i915: Fix LVDS stability issue on Ironlake
In disable sequence, all output ports on PCH have to be disabled
before PCH transcoder, but LVDS port was left always enabled. This
one fixes that by disable LVDS port properly during pipe disable
process, and resolved stability issue seen on Ironlake. Also move
panel fitting disable time just after pipe disable to align with
the spec.

Signed-off-by: Zhenyu Wang <zhenyuw@linux.intel.com>
Signed-off-by: Eric Anholt <eric@anholt.net>
2009-11-25 13:09:35 -08:00
Zhao Yakui
4215866059 drm/i915: Restore the DPLL calculation logic for 9xx platform
The DPLL calculation logic for 9xx platform is changed in:
commit 652c393a33
Author: Jesse Barnes <jbarnes@virtuousgeek.org>
Date:   Mon Aug 17 13:31:43 2009 -0700

    drm/i915: add dynamic clock frequency control

Maybe we will get the different M/N/P combination with that by using the
previous dpll calculation logic.

So restore the DPLL calculation logic for 9xx platform.

Signed-off-by: Zhao Yakui <yakui.zhao@intel.com>
Reviewed-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: Eric Anholt <eric@anholt.net>
2009-11-25 13:03:12 -08:00
Zhao Yakui
d1fcea6a52 drm/i915: Check whether the LVDS downclock is found in VBT
Enumerate the LVDS panel timing info entry list in VBT to check whether
the LVDS downclock is found. If found, the downclock is also used to switch
dynamically between low and high frequency for LVDS.

Signed-off-by: Zhao Yakui <yakui.zhao@intel.com>
Acked-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: Eric Anholt <eric@anholt.net>
2009-11-25 13:02:33 -08:00
Zhao Yakui
18f9ed12f8 drm/i915: Enable LVDS downclock feature through EDID.
If more than one mode with the same resolution defined in EDID has different
refresh rate, it is thought that the downclock is found for LVDS.
We will program the different FPx0/1 register so that we can select dynamically
between the low and high frequency.

On the g4x platform we will use the CxSR feature to switch the different
refresh rate if the LVDS downclock feature is supported.

Signed-off-by: Zhao Yakui <yakui.zhao@intel.com>
Reviewed-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: Eric Anholt <eric@anholt.net>
2009-11-25 12:46:41 -08:00
Eric Anholt
c8e0f93a38 drm/i915: Replace a calloc followed by copying data over it with malloc.
Execbufs involve quite a bit of payload, to the extent that cache misses
show up in the profiles here, and a suspicion that some of those cachelines
may get evicted and then reloaded in the subsequent copy.

This is still abstracted like drm_calloc_large since we want to check for
size overflow, and because we want to choose between kmalloc and vmalloc
on the fly.  cairo's interface for malloc-with-calloc's-args was used as
the model.

Signed-off-by: Eric Anholt <eric@anholt.net>
2009-11-25 06:36:21 -08:00
Eric Anholt
5b8f0be0dc Merge remote branch 'airlied/drm-next' into drm-intel-next 2009-11-05 15:04:06 -08:00
Daniel Vetter
43bcd61fae drm/i915: fix get_core_clock_speed for G33 class desktop chips
Somehow the case for G33 got dropped while porting from ums code.
This made a 400MHz chip into a 133MHz one which resulted in the
unnecessary enabling of double wide pipe mode which in turn
screwed up the overlay code.

Nothing else (than the overlay code) seems to be affected.

This fixes fdo.org bug #24835

Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Eric Anholt <eric@anholt.net>
2009-11-05 14:57:39 -08:00
Zhenyu Wang
c650156af3 drm/i915: Add display hotplug event on Ironlake
Enable display hotplug irqs from Ibex Peak (PCH).

Signed-off-by: Zhenyu Wang <zhenyuw@linux.intel.com>
Signed-off-by: Eric Anholt <eric@anholt.net>
2009-11-05 14:49:37 -08:00
Zhao Yakui
01c66889c1 drm/i915: Add ACPI OpRegion support for Ironlake
Add the support of ACPI opregion on Ironlake so that the backlight
brightness can be adjusted by using ACPI interface
   >/sys/class/backlight/acpi_video0/brightness

Signed-off-by: Zhao Yakui <yakui.zhao@intel.com>
Tested-by: Zhao Yakui <yakui.zhao@intel.com>
[zhenyuw: cleanups, fix typo for checking GSE irq and convert to
current irq handling logic.]
Signed-off-by: Zhenyu Wang <zhenyuw@linux.intel.com>
Signed-off-by: Eric Anholt <eric@anholt.net>
2009-11-05 14:49:13 -08:00
Jesse Barnes
1dc7546d1a drm/i915: enable self-refresh on 965
Need to calculate the SR watermark and enable it.

Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: Eric Anholt <eric@anholt.net>
2009-11-05 14:47:14 -08:00
Kristian Høgsberg
a4f45cf178 drm/i915: Support 30 bit depth modes
Signed-off-by: Kristian Høgsberg <krh@redhat.com>
Signed-off-by: Eric Anholt <eric@anholt.net>
2009-11-05 14:47:13 -08:00
Chris Wilson
f3cd474bb2 drm/i915: debugfs interface to manually reset the GPU
Create a /debug/dri/%d/i915_wedged file to display the current wedged
status, and to enable setting that value. On an i965, this will also
trigger a GPU reset.

Useful in order to attempt to recover from some error conditions that
are not currently caught by the automatic hang detection code.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Eric Anholt <eric@anholt.net>
2009-11-05 14:47:13 -08:00
Chris Wilson
aed5f1dc26 drm/i915: Use a single thread workqueue
Our work is serialised so allocating per-cpu workqueues is overkill and
a waste of resources.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Eric Anholt <eric@anholt.net>
2009-11-05 14:47:12 -08:00
Zhao Yakui
d0c3b04ae9 drm/i915: Replace DRM_DEBUG with DRM_DEBUG_KMS in DVO output code.
Signed-off-by: Zhao Yakui <yakui.zhao@intel.com>
Signed-off-by: Eric Anholt <eric@anholt.net>
2009-11-05 14:47:12 -08:00
Eric Anholt
3e0f27ed75 drm/i915: Enable the SDVO debug code, which is now under DEBUG_KMS.
Signed-off-by: Eric Anholt <eric@anholt.net>
2009-11-05 14:47:11 -08:00
Zhao Yakui
28c97730c3 drm/i915: Replace DRM_DEBUG with DRM_DEBUG_KMS
Replace the DRM_DEBUG with DRM_DEBUG_KMS in output device code.

Signed-off-by: Zhao Yakui <yakui.zhao@intel.com>
Signed-off-by: Eric Anholt <eric@anholt.net>
2009-11-05 14:47:11 -08:00
Zhao Yakui
44d98a6142 drm/i915: Replace DRM_DEBUG with DRM_DEBUG_DRIVER
Replace the DRM_DEBUG with DRM_DEBUG_DRIVER in generic i915 driver.
Then the debug info can be obtained by adding the boot option of
"drm.debug=0x02".

At the same time the debug info in increase/decrease clock is also
printed by using DRM_DEBUG_DRIVER instead of DRM_DEBUG_KMS.

Signed-off-by: Zhao Yakui <yakui.zhao@intel.com>
Signed-off-by: Eric Anholt <eric@anholt.net>
2009-11-05 14:47:10 -08:00
Daniel Vetter
5c5a4359fe drm/i915: overlay: kill one more unnecessary uninterruptible sleep
I've simply overlooked one case in the conversion to interruptible
sleeps. Rectify this.

Also delete a leftover debug printk.

Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Eric Anholt <eric@anholt.net>
2009-11-05 14:47:10 -08:00
Daniel Vetter
1df4b35b61 drm/i915: kill i915_lp_ring_sync
It's not needed anymore.

Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Eric Anholt <eric@anholt.net>
2009-11-05 14:47:09 -08:00
Daniel Vetter
03f77ea597 drm/i915: implement interruptible sleeps in the overlay code
At least for the common case of userspace ioctls. When doing a
modeset operation, the wait is still uninterruptible. But considering
that failing to turn off the overlay when switching off the crtc it's
running on hangs the chip, it doesn't complicate matters _very_
much. There's just an unkillable X in addition to a black screen.
BUG() about it and explain in the code.

Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Eric Anholt <eric@anholt.net>
2009-11-05 14:47:09 -08:00
Daniel Vetter
5a5a0c64a9 drm/i915: implement fastpath for overlay flip waiting
As long as the gpu can keep up, neither the cpu (waiting for gpu)
nore the gpu (waiting for vblank to do an overlay flip) stalls.

Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Eric Anholt <eric@anholt.net>
2009-11-05 14:47:09 -08:00
Daniel Vetter
240a2d12df drm/i915: fully switch off overlay when not in use
Now that the cache flushing of the memory based overlay regs works,
we can safely switch off the overlay. Beforehand it was only disabled
(like in userspace).

Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Eric Anholt <eric@anholt.net>
2009-11-05 14:47:08 -08:00
Daniel Vetter
02e792fbaa drm/i915: implement drmmode overlay support v4
This implements intel overlay support for kms via a device-specific
ioctl. Thomas Hellstrom brought up the idea of a general ioctl (on
dri-devel). We've reached the conclusion that such an infrastructure
only makes sense when multiple kms overlay implementations exists,
which atm don't (and it doesn't look like this is gonna change).

Open issues:
- Runs in sync with the gpu, i.e. unnecessary waiting. I've decided
  to wait on this because the hw tends to hang when changing something
  in this area. I left some dummy functions as infrastructure.
- polyphase filtering uses a static table.
- uses uninterruptible sleeps. Unfortunately the alternatives may
  unnecessarily wedged the hw if/when we timeout too early (and
  userspace only overloaded the batch buffers with stuff worth a few
  secs of gpu time).

Changes since v1:
- fix off-by-one misconception on my side. This fixes fullscreen
  playback.
Changes since v2:
- add underrun detection as spec'ed for i965.
- flush caches properly, fixing visual corruptions.
Changes since v4:
- fix up cache flushing of overlay memory regs.
- killed require_pipe_a logic - it hangs the chip.

Tested-By: diego.abelenda@gmail.com (on a 865G)
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
[anholt: Resolved against the MADVISE ioctl going in before this one]
Signed-off-by: Eric Anholt <eric@anholt.net>
2009-11-05 14:47:08 -08:00
Daniel Vetter
f0f8a9cece drm/i915: kill superflous IS_I855 macro
It is identical to I85X. Use that one instead.

Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
[anholt: fix conflicts against the display function pointer stuff]
Signed-off-by: Eric Anholt <eric@anholt.net>
2009-11-05 14:47:07 -08:00
Daniel Vetter
48764bf43f drm/i915: add i915_lp_ring_sync helper
This just waits until the hw passed the current ring position with
cmd execution. This slightly changes the existing i915_wait_request
function to make uninterruptible waiting possible - no point in
returning to userspace while mucking around with the overlay, that
piece of hw is just too fragile.

Also replace a magic 0 with the symbolic constant (and kill the then
superflous comment) while I was looking at the code.

Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Eric Anholt <eric@anholt.net>
2009-11-05 14:47:07 -08:00