<feed xmlns='http://www.w3.org/2005/Atom'>
<title>linux-toradex.git/drivers/gpu/drm/i915, branch v3.5.4</title>
<subtitle>Linux kernel for Apalis and Colibri modules</subtitle>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/'/>
<entry>
<title>drm/i915: make rc6 in sysfs functions conditional</title>
<updated>2012-08-26T02:31:40+00:00</updated>
<author>
<name>Hunt Xu</name>
<email>mhuntxu@gmail.com</email>
</author>
<published>2012-07-01T03:45:07+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=4267ea6bdb984ecda4aa042136e167944a397934'/>
<id>4267ea6bdb984ecda4aa042136e167944a397934</id>
<content type='text'>
commit 5ab3633d6907018b0b830a720e877c3884d679c3 upstream.

Commit 0136db586c028f71e7cc21cc183064ff0d5919c8 merges rc6 information
into the power group. However, when compiled with CONFIG_PM not set,
modprobing i915 would taint since power_group_name is defined as NULL.

This patch makes these rc6 in sysfs functions conditional upon the
definition of the CONFIG_PM macro to avoid the above-mentioned problem.

Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=45181
Tested-by: Kris Karas &lt;bugs-a12@moonlit-rail.com&gt;
Signed-off-by: Hunt Xu &lt;mhuntxu@gmail.com&gt;
Signed-off-by: Daniel Vetter &lt;daniel.vetter@ffwll.ch&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;

</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
commit 5ab3633d6907018b0b830a720e877c3884d679c3 upstream.

Commit 0136db586c028f71e7cc21cc183064ff0d5919c8 merges rc6 information
into the power group. However, when compiled with CONFIG_PM not set,
modprobing i915 would taint since power_group_name is defined as NULL.

This patch makes these rc6 in sysfs functions conditional upon the
definition of the CONFIG_PM macro to avoid the above-mentioned problem.

Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=45181
Tested-by: Kris Karas &lt;bugs-a12@moonlit-rail.com&gt;
Signed-off-by: Hunt Xu &lt;mhuntxu@gmail.com&gt;
Signed-off-by: Daniel Vetter &lt;daniel.vetter@ffwll.ch&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;

</pre>
</div>
</content>
</entry>
<entry>
<title>drm/i915: reorder edp disabling to fix ivb MacBook Air</title>
<updated>2012-08-26T02:31:40+00:00</updated>
<author>
<name>Daniel Vetter</name>
<email>daniel.vetter@ffwll.ch</email>
</author>
<published>2012-08-12T20:17:14+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=8cb97b1434fc3d150ef954f959e0c27c21ca2790'/>
<id>8cb97b1434fc3d150ef954f959e0c27c21ca2790</id>
<content type='text'>
commit 35a38556d900b9cb5dfa2529c93944b847f8a8a4 upstream.

eDP is tons of fun. It turns out that at least the new MacBook Air 5,1
model absolutely doesn't like the new force vdd dance we've introduced
in

commit 6cb49835da0426f69a2931bc2a0a8156344b0e41
Author: Daniel Vetter &lt;daniel.vetter@ffwll.ch&gt;
Date:   Sun May 20 17:14:50 2012 +0200

    drm/i915: enable vdd when switching off the eDP panel

But that patch also tried to fix some neat edp sequence issue with the
force_vdd timings. Closer inspection reveals that we've raised
force_vdd only to do the aux channel communication dp_sink_dpms. If we
move the edp_panel_off below that, we don't need any force_vdd for the
disable sequence, which makes the Air happy.

Unfortunately the reporter of the original bug that the above commit
fixed is travelling, so we can't test whether this regresses things.
But my theory is that since we don't check for any power-off -&gt;
force_vdd-on delays in edp_panel_vdd_on, this was the actual
root-cause of this failure. With that force_vdd dance completely
eliminated, I'm hopeful the original bug stays fixed, too.

For reference the old bug, which hopefully doesn't get broken by this:

https://bugzilla.kernel.org/show_bug.cgi?id=43163

In any case, regression fixers win over plain bugfixes, so this needs
to go in asap.

v2: The crucial pieces seems to be to clear the force_vdd flag
uncoditionally, too, in edp_panel_off. Looks like this is left behind
by the firmware somehow.

v3: The Apple firmware seems to switch off the panel on it's own, hence
we still need to keep force_vdd on, but properly clear it when switching
the panel off.

Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=45671
Tested-by: Roberto Romer &lt;sildurin@gmail.com&gt;
Tested-by: Daniel Wagner &lt;wagi@monom.org&gt;
Tested-by: Keith Packard &lt;keithp@keithp.com&gt;
Cc: Keith Packard &lt;keithp@keithp.com&gt;
Signed-off-by: Daniel Vetter &lt;daniel.vetter@ffwll.ch&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;

</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
commit 35a38556d900b9cb5dfa2529c93944b847f8a8a4 upstream.

eDP is tons of fun. It turns out that at least the new MacBook Air 5,1
model absolutely doesn't like the new force vdd dance we've introduced
in

commit 6cb49835da0426f69a2931bc2a0a8156344b0e41
Author: Daniel Vetter &lt;daniel.vetter@ffwll.ch&gt;
Date:   Sun May 20 17:14:50 2012 +0200

    drm/i915: enable vdd when switching off the eDP panel

But that patch also tried to fix some neat edp sequence issue with the
force_vdd timings. Closer inspection reveals that we've raised
force_vdd only to do the aux channel communication dp_sink_dpms. If we
move the edp_panel_off below that, we don't need any force_vdd for the
disable sequence, which makes the Air happy.

Unfortunately the reporter of the original bug that the above commit
fixed is travelling, so we can't test whether this regresses things.
But my theory is that since we don't check for any power-off -&gt;
force_vdd-on delays in edp_panel_vdd_on, this was the actual
root-cause of this failure. With that force_vdd dance completely
eliminated, I'm hopeful the original bug stays fixed, too.

For reference the old bug, which hopefully doesn't get broken by this:

https://bugzilla.kernel.org/show_bug.cgi?id=43163

In any case, regression fixers win over plain bugfixes, so this needs
to go in asap.

v2: The crucial pieces seems to be to clear the force_vdd flag
uncoditionally, too, in edp_panel_off. Looks like this is left behind
by the firmware somehow.

v3: The Apple firmware seems to switch off the panel on it's own, hence
we still need to keep force_vdd on, but properly clear it when switching
the panel off.

Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=45671
Tested-by: Roberto Romer &lt;sildurin@gmail.com&gt;
Tested-by: Daniel Wagner &lt;wagi@monom.org&gt;
Tested-by: Keith Packard &lt;keithp@keithp.com&gt;
Cc: Keith Packard &lt;keithp@keithp.com&gt;
Signed-off-by: Daniel Vetter &lt;daniel.vetter@ffwll.ch&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;

</pre>
</div>
</content>
</entry>
<entry>
<title>drm/i915: ignore eDP bpc settings from vbt</title>
<updated>2012-08-26T02:31:40+00:00</updated>
<author>
<name>Daniel Vetter</name>
<email>daniel.vetter@ffwll.ch</email>
</author>
<published>2012-08-10T09:10:20+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=33fbdc047b30be3781d0b861adb6ef96fa052355'/>
<id>33fbdc047b30be3781d0b861adb6ef96fa052355</id>
<content type='text'>
commit 4344b813f105a19f793f1fd93ad775b784648b95 upstream.

This has originally been introduced to not oversubscribe the dp links
in

commit 885a5fb5b120a5c7e0b3baad7b0feb5a89f76c18
Author: Zhenyu Wang &lt;zhenyuw@linux.intel.com&gt;
Date:   Tue Jan 12 05:38:31 2010 +0800

    drm/i915: fix pixel color depth setting on eDP

Since then we've fixed up the dp link bandwidth calculation code and
should now automatically fall back to 6bpc dithering. So this is
unnecessary.

Furthermore it seems to break the new MacbookPro with retina display,
hence let's just rip this out.

Reported-by: Benoit Gschwind &lt;gschwind@gnu-log.net&gt;
Cc: Benoit Gschwind &lt;gschwind@gnu-log.net&gt;
Cc: Francois Rigaut &lt;frigaut@gmail.com&gt;
Tested-by: Benoit Gschwind &lt;gschwind@gnu-log.net&gt;
Tested-by: Bernhard Froemel &lt;froemel at vmars tuwien.ac.at&gt;
Signed-off-by: Daniel Vetter &lt;daniel.vetter@ffwll.ch&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;

--

Testing feedback highgly welcome, and thanks for Benoit for finding
out that the bpc computations are busted.
-Daniel

</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
commit 4344b813f105a19f793f1fd93ad775b784648b95 upstream.

This has originally been introduced to not oversubscribe the dp links
in

commit 885a5fb5b120a5c7e0b3baad7b0feb5a89f76c18
Author: Zhenyu Wang &lt;zhenyuw@linux.intel.com&gt;
Date:   Tue Jan 12 05:38:31 2010 +0800

    drm/i915: fix pixel color depth setting on eDP

Since then we've fixed up the dp link bandwidth calculation code and
should now automatically fall back to 6bpc dithering. So this is
unnecessary.

Furthermore it seems to break the new MacbookPro with retina display,
hence let's just rip this out.

Reported-by: Benoit Gschwind &lt;gschwind@gnu-log.net&gt;
Cc: Benoit Gschwind &lt;gschwind@gnu-log.net&gt;
Cc: Francois Rigaut &lt;frigaut@gmail.com&gt;
Tested-by: Benoit Gschwind &lt;gschwind@gnu-log.net&gt;
Tested-by: Bernhard Froemel &lt;froemel at vmars tuwien.ac.at&gt;
Signed-off-by: Daniel Vetter &lt;daniel.vetter@ffwll.ch&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;

--

Testing feedback highgly welcome, and thanks for Benoit for finding
out that the bpc computations are busted.
-Daniel

</pre>
</div>
</content>
</entry>
<entry>
<title>drm/i915: correctly order the ring init sequence</title>
<updated>2012-08-26T02:31:40+00:00</updated>
<author>
<name>Daniel Vetter</name>
<email>daniel.vetter@ffwll.ch</email>
</author>
<published>2012-08-07T07:54:14+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=622ecb9ace2ec006b58f6779732961945ea303ca'/>
<id>622ecb9ace2ec006b58f6779732961945ea303ca</id>
<content type='text'>
commit 0d8957c8a90bbb5d34fab9a304459448a5131e06 upstream.

We may only start to set up the new register values after having
confirmed that the ring is truely off. Otherwise the hw might lose the
newly written register values. This is caught later on in the init
sequence, when we check whether the register writes have stuck.

Reviewed-by: Jani Nikula &lt;jani.nikula@intel.com&gt;
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=50522
Tested-by: Yang Guang &lt;guang.a.yang@intel.com&gt;
Signed-off-by: Daniel Vetter &lt;daniel.vetter@ffwll.ch&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;

</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
commit 0d8957c8a90bbb5d34fab9a304459448a5131e06 upstream.

We may only start to set up the new register values after having
confirmed that the ring is truely off. Otherwise the hw might lose the
newly written register values. This is caught later on in the init
sequence, when we check whether the register writes have stuck.

Reviewed-by: Jani Nikula &lt;jani.nikula@intel.com&gt;
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=50522
Tested-by: Yang Guang &lt;guang.a.yang@intel.com&gt;
Signed-off-by: Daniel Vetter &lt;daniel.vetter@ffwll.ch&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;

</pre>
</div>
</content>
</entry>
<entry>
<title>drm/i915: prefer wide &amp; slow to fast &amp; narrow in DP configs</title>
<updated>2012-08-26T02:31:39+00:00</updated>
<author>
<name>Jesse Barnes</name>
<email>jbarnes@virtuousgeek.org</email>
</author>
<published>2012-06-21T22:13:50+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=2a76966382c049fe15b9f34d4e495cdc9d2c6e9f'/>
<id>2a76966382c049fe15b9f34d4e495cdc9d2c6e9f</id>
<content type='text'>
commit 2514bc510d0c3aadcc5204056bb440fa36845147 upstream.

High frequency link configurations have the potential to cause trouble
with long and/or cheap cables, so prefer slow and wide configurations
instead.  This patch has the potential to cause trouble for eDP
configurations that lie about available lanes, so if we run into that we
can make it conditional on eDP.

Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=45801
Tested-by: peter@colberg.org
Signed-off-by: Jesse Barnes &lt;jbarnes@virtuousgeek.org&gt;
Signed-off-by: Daniel Vetter &lt;daniel.vetter@ffwll.ch&gt;
Cc: Jonathan Nieder &lt;jrnieder@gmail.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;

</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
commit 2514bc510d0c3aadcc5204056bb440fa36845147 upstream.

High frequency link configurations have the potential to cause trouble
with long and/or cheap cables, so prefer slow and wide configurations
instead.  This patch has the potential to cause trouble for eDP
configurations that lie about available lanes, so if we run into that we
can make it conditional on eDP.

Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=45801
Tested-by: peter@colberg.org
Signed-off-by: Jesse Barnes &lt;jbarnes@virtuousgeek.org&gt;
Signed-off-by: Daniel Vetter &lt;daniel.vetter@ffwll.ch&gt;
Cc: Jonathan Nieder &lt;jrnieder@gmail.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;

</pre>
</div>
</content>
</entry>
<entry>
<title>drm/i915: kick any firmware framebuffers before claiming the gtt</title>
<updated>2012-07-03T10:18:48+00:00</updated>
<author>
<name>Daniel Vetter</name>
<email>daniel.vetter@ffwll.ch</email>
</author>
<published>2012-07-01T15:09:42+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=9f846a16d213523fbe6daea17e20df6b8ac5a1e5'/>
<id>9f846a16d213523fbe6daea17e20df6b8ac5a1e5</id>
<content type='text'>
Especially vesafb likes to map everything as uc- (yikes), and if that
mapping hangs around still while we try to map the gtt as wc the
kernel will downgrade our request to uc-, resulting in abyssal
performance.

Unfortunately we can't do this as early as readon does (i.e. as the
first thing we do when initializing the hw) because our fb/mmio space
region moves around on a per-gen basis. So I've had to move it below
the gtt initialization, but that seems to work, too. The important
thing is that we do this before we set up the gtt wc mapping.

Now an altogether different question is why people compile their
kernels with vesafb enabled, but I guess making things just work isn't
bad per se ...

v2:
- s/radeondrmfb/inteldrmfb/
- fix up error handling

v3: Kill #ifdef X86, this is Intel after all. Noticed by Ben Widawsky.

v4: Jani Nikula complained about the pointless bool primary
initialization.

v5: Don't oops if we can't allocate, noticed by Chris Wilson.

v6: Resolve conflicts with agp rework and fixup whitespace.

This is commit e188719a2891f01b3100d in drm-next.

Backport to 3.5 -fixes queue requested by Dave Airlie - due to grub
using vesa on fedora their initrd seems to load vesafb before loading
the real kms driver. So tons more people actually experience a
dead-slow gpu. Hence also the Cc: stable.

Cc: stable@vger.kernel.org
Reported-and-tested-by: "Kilarski, Bernard R" &lt;bernard.r.kilarski@intel.com&gt;
Reviewed-by: Chris Wilson &lt;chris@chris-wilson.co.uk&gt;
Signed-off-by: Daniel Vetter &lt;daniel.vetter@ffwll.ch&gt;
Signed-off-by: Dave Airlie &lt;airlied@redhat.com&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Especially vesafb likes to map everything as uc- (yikes), and if that
mapping hangs around still while we try to map the gtt as wc the
kernel will downgrade our request to uc-, resulting in abyssal
performance.

Unfortunately we can't do this as early as readon does (i.e. as the
first thing we do when initializing the hw) because our fb/mmio space
region moves around on a per-gen basis. So I've had to move it below
the gtt initialization, but that seems to work, too. The important
thing is that we do this before we set up the gtt wc mapping.

Now an altogether different question is why people compile their
kernels with vesafb enabled, but I guess making things just work isn't
bad per se ...

v2:
- s/radeondrmfb/inteldrmfb/
- fix up error handling

v3: Kill #ifdef X86, this is Intel after all. Noticed by Ben Widawsky.

v4: Jani Nikula complained about the pointless bool primary
initialization.

v5: Don't oops if we can't allocate, noticed by Chris Wilson.

v6: Resolve conflicts with agp rework and fixup whitespace.

This is commit e188719a2891f01b3100d in drm-next.

Backport to 3.5 -fixes queue requested by Dave Airlie - due to grub
using vesa on fedora their initrd seems to load vesafb before loading
the real kms driver. So tons more people actually experience a
dead-slow gpu. Hence also the Cc: stable.

Cc: stable@vger.kernel.org
Reported-and-tested-by: "Kilarski, Bernard R" &lt;bernard.r.kilarski@intel.com&gt;
Reviewed-by: Chris Wilson &lt;chris@chris-wilson.co.uk&gt;
Signed-off-by: Daniel Vetter &lt;daniel.vetter@ffwll.ch&gt;
Signed-off-by: Dave Airlie &lt;airlied@redhat.com&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>Revert "drm/i915: allow PCH PWM override on IVB"</title>
<updated>2012-06-27T18:26:30+00:00</updated>
<author>
<name>Daniel Vetter</name>
<email>daniel.vetter@ffwll.ch</email>
</author>
<published>2012-06-27T14:43:36+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=7aa1e7f06d6ea1bce3b27630d50769d13da28b1a'/>
<id>7aa1e7f06d6ea1bce3b27630d50769d13da28b1a</id>
<content type='text'>
This reverts commit f82cfb6bcda164ef3a66b8c3fc549b1f9bdd09ad.

This breaks the backlight controls on my IVB asus zenbook with an eDP
panel.

I guess the right fix would be to read this bit and use either the pch
or the cpu register to frob the backlight values. But that is stuff
for -next.

Cc: Jesse Barnes &lt;jbarnes@virtuousgeek.org&gt;
Signed-Off-by: Daniel Vetter &lt;daniel.vetter@ffwll.ch&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
This reverts commit f82cfb6bcda164ef3a66b8c3fc549b1f9bdd09ad.

This breaks the backlight controls on my IVB asus zenbook with an eDP
panel.

I guess the right fix would be to read this bit and use either the pch
or the cpu register to frob the backlight values. But that is stuff
for -next.

Cc: Jesse Barnes &lt;jbarnes@virtuousgeek.org&gt;
Signed-Off-by: Daniel Vetter &lt;daniel.vetter@ffwll.ch&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>drm/i915: Fix eDP blank screen after S3 resume on HP desktops</title>
<updated>2012-06-22T22:01:42+00:00</updated>
<author>
<name>Takashi Iwai</name>
<email>tiwai@suse.de</email>
</author>
<published>2012-06-21T13:30:41+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=6db65cbb941f9d433659bdad02b307f6d94465df'/>
<id>6db65cbb941f9d433659bdad02b307f6d94465df</id>
<content type='text'>
This patch fixes the problem on some HP desktop machines with eDP
which give blank screens after S3 resume.

It turned out that BLC_PWM_CPU_CTL must be written after
BLC_PWM_CPU_CTL2.  Otherwise it doesn't take effect on these
SNB machines.

Tested with 3.5-rc3 kernel.

Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=49233

Cc: &lt;stable@vger.kernel.org&gt;
Signed-off-by: Takashi Iwai &lt;tiwai@suse.de&gt;
Signed-off-by: Daniel Vetter &lt;daniel.vetter@ffwll.ch&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
This patch fixes the problem on some HP desktop machines with eDP
which give blank screens after S3 resume.

It turned out that BLC_PWM_CPU_CTL must be written after
BLC_PWM_CPU_CTL2.  Otherwise it doesn't take effect on these
SNB machines.

Tested with 3.5-rc3 kernel.

Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=49233

Cc: &lt;stable@vger.kernel.org&gt;
Signed-off-by: Takashi Iwai &lt;tiwai@suse.de&gt;
Signed-off-by: Daniel Vetter &lt;daniel.vetter@ffwll.ch&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>drm/i915: rip out the PM_IIR WARN</title>
<updated>2012-06-22T22:01:41+00:00</updated>
<author>
<name>Daniel Vetter</name>
<email>daniel.vetter@ffwll.ch</email>
</author>
<published>2012-06-21T12:55:22+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=58bf8062d0b293b8e1028e5b0342082002886bd4'/>
<id>58bf8062d0b293b8e1028e5b0342082002886bd4</id>
<content type='text'>
After banging my head against this for the past few months, I still
don't see how this could possible race under the premise that once an
irq bit is masked in PM_IMR and reset in PM_IIR it won't show up again
until we unmask it in PM_IMR.

Still, we have reports of this being seen in the wild. Now Bspec has
this little bit of lovely language in the PMIIR register:

Public SNB Docs, Vol3Part2, 2.5.14 "PMIIR":

"For each bit, the IIR can store a second pending interrupt if two or
more of the same interrupt conditions occur before the first condition
is cleared. Upon clearing the interrupt, the IIR bit will momentarily
go low, then return high to indicate there is another interrupt
pending."

Now if we presume that PMIMR only prevent new interrupts from being
queued, we could easily end up masking an interrupt and clearing it,
but the 2nd pending interrupt setting the bit in PMIIR right away
again. Which leads, the next time the irq handler runs, to hitting the
WARN.

Also, no bad side effects of this have ever been reported. And we've
tracked down our issues with the gpu turbo getting stuck to bogus
interrupt generation limits in th RPLIMIT register.

So let's just rip out this WARN as bogus and call it a day. The only
shallow thing here is that this 2-deep irq queue in the hw makes you
wonder how racy the windows irq handler is ...

Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=42907
Cc: stable@vger.kernel.org
Acked-by: Chris Wilson &lt;chris@chris-wilson.co.uk&gt;
Signed-Off-by: Daniel Vetter &lt;daniel.vetter@ffwll.ch&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
After banging my head against this for the past few months, I still
don't see how this could possible race under the premise that once an
irq bit is masked in PM_IMR and reset in PM_IIR it won't show up again
until we unmask it in PM_IMR.

Still, we have reports of this being seen in the wild. Now Bspec has
this little bit of lovely language in the PMIIR register:

Public SNB Docs, Vol3Part2, 2.5.14 "PMIIR":

"For each bit, the IIR can store a second pending interrupt if two or
more of the same interrupt conditions occur before the first condition
is cleared. Upon clearing the interrupt, the IIR bit will momentarily
go low, then return high to indicate there is another interrupt
pending."

Now if we presume that PMIMR only prevent new interrupts from being
queued, we could easily end up masking an interrupt and clearing it,
but the 2nd pending interrupt setting the bit in PMIIR right away
again. Which leads, the next time the irq handler runs, to hitting the
WARN.

Also, no bad side effects of this have ever been reported. And we've
tracked down our issues with the gpu turbo getting stuck to bogus
interrupt generation limits in th RPLIMIT register.

So let's just rip out this WARN as bogus and call it a day. The only
shallow thing here is that this 2-deep irq queue in the hw makes you
wonder how racy the windows irq handler is ...

Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=42907
Cc: stable@vger.kernel.org
Acked-by: Chris Wilson &lt;chris@chris-wilson.co.uk&gt;
Signed-Off-by: Daniel Vetter &lt;daniel.vetter@ffwll.ch&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>drm/i915: cache the EDID for eDP panels</title>
<updated>2012-06-16T13:39:02+00:00</updated>
<author>
<name>Jesse Barnes</name>
<email>jbarnes@virtuousgeek.org</email>
</author>
<published>2012-06-14T19:28:33+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=d6f24d0fa6cdf3431a2fe3330a74bc6c5871f496'/>
<id>d6f24d0fa6cdf3431a2fe3330a74bc6c5871f496</id>
<content type='text'>
They aren't going anywhere, and probing on DDC can cause the panel to
blank briefly, so read them up front and cache them for later queries.

v2: fix potential NULL derefs in intel_dp_get_edid_modes and
    intel_dp_get_edid (Jani)
    copy full EDID length, including extension blocks (Takashi)
    free EDID on teardown (Takashi)
v3: malloc a new EDID buffer that's big enough for the memcpy (Chris)
v4: change handling of NULL EDIDs, just preserve the NULL behavior
    across detects and mode list fetches rather than trying to re-fetch
    the EDID (Chris)
v5: be glad that Chris is around to remind me to hit C-x C-s before
    committing.

References: https://bugs.freedesktop.org/show_bug.cgi?id=46856
Signed-off-by: Jesse Barnes &lt;jbarnes@virtuousgeek.org&gt;
Signed-off-by: Daniel Vetter &lt;daniel.vetter@ffwll.ch&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
They aren't going anywhere, and probing on DDC can cause the panel to
blank briefly, so read them up front and cache them for later queries.

v2: fix potential NULL derefs in intel_dp_get_edid_modes and
    intel_dp_get_edid (Jani)
    copy full EDID length, including extension blocks (Takashi)
    free EDID on teardown (Takashi)
v3: malloc a new EDID buffer that's big enough for the memcpy (Chris)
v4: change handling of NULL EDIDs, just preserve the NULL behavior
    across detects and mode list fetches rather than trying to re-fetch
    the EDID (Chris)
v5: be glad that Chris is around to remind me to hit C-x C-s before
    committing.

References: https://bugs.freedesktop.org/show_bug.cgi?id=46856
Signed-off-by: Jesse Barnes &lt;jbarnes@virtuousgeek.org&gt;
Signed-off-by: Daniel Vetter &lt;daniel.vetter@ffwll.ch&gt;
</pre>
</div>
</content>
</entry>
</feed>
