<feed xmlns='http://www.w3.org/2005/Atom'>
<title>linux-toradex.git/drivers/gpu/drm/i915, branch v3.19</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: BDW Fix Halo PCI IDs marked as ULT.</title>
<updated>2015-01-26T09:00:34+00:00</updated>
<author>
<name>Rodrigo Vivi</name>
<email>rodrigo.vivi@intel.com</email>
</author>
<published>2015-01-20T00:16:15+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=6b96d705f3cf435b0b8835b12c9742513c77fed6'/>
<id>6b96d705f3cf435b0b8835b12c9742513c77fed6</id>
<content type='text'>
BDW with PCI-IDs ended in "2" aren't ULT, but HALO.
Let's fix it and at least allow VGA to work on this units.

v2: forgot ammend and v1 doesn't compile

Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=87220
Cc: Xion Zhang &lt;xiong.y.zhang@intel.com&gt;
Cc: Guo Jinxian &lt;jinxianx.guo@intel.com&gt;
Cc: Jani Nikula &lt;jani.nikula@intel.com&gt;
Cc: Stable &lt;stable@vger.kernel.org&gt;
Signed-off-by: Rodrigo Vivi &lt;rodrigo.vivi@intel.com&gt;
Signed-off-by: Jani Nikula &lt;jani.nikula@intel.com&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
BDW with PCI-IDs ended in "2" aren't ULT, but HALO.
Let's fix it and at least allow VGA to work on this units.

v2: forgot ammend and v1 doesn't compile

Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=87220
Cc: Xion Zhang &lt;xiong.y.zhang@intel.com&gt;
Cc: Guo Jinxian &lt;jinxianx.guo@intel.com&gt;
Cc: Jani Nikula &lt;jani.nikula@intel.com&gt;
Cc: Stable &lt;stable@vger.kernel.org&gt;
Signed-off-by: Rodrigo Vivi &lt;rodrigo.vivi@intel.com&gt;
Signed-off-by: Jani Nikula &lt;jani.nikula@intel.com&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>drm/i915: Fix and clean BDW PCH identification</title>
<updated>2015-01-26T09:00:34+00:00</updated>
<author>
<name>Rodrigo Vivi</name>
<email>rodrigo.vivi@intel.com</email>
</author>
<published>2015-01-21T18:33:53+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=a35cc9d0c0118fb18f7c5dd7a44adb454868a679'/>
<id>a35cc9d0c0118fb18f7c5dd7a44adb454868a679</id>
<content type='text'>
It seems in the past we have BDW with PCH not been propperly identified
and we force it to be LPT and we were warning !IS_HASWELL on propper identification.

Now that products are out there we are receiveing logs with this incorrect WARN.
And also according to local tests on all production BDW here ULT or HALO we don't
need this force anymore. So let's clean this block for real.

v2: Fix LPT_LP WARNs to avoid wrong warns on BDW_ULT (By Jani).

Reference: https://bugs.freedesktop.org/attachment.cgi?id=110972

Cc: Jani Nikula &lt;jani.nikula@intel.com&gt;
Cc: Paulo Zanoni &lt;paulo.r.zanoni@intel.com&gt;
Cc: Xion Zhang &lt;xiong.y.zhang@intel.com&gt;
Cc: stable@vger.kernel.org
Signed-off-by: Rodrigo Vivi &lt;rodrigo.vivi@intel.com&gt;
Signed-off-by: Jani Nikula &lt;jani.nikula@intel.com&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
It seems in the past we have BDW with PCH not been propperly identified
and we force it to be LPT and we were warning !IS_HASWELL on propper identification.

Now that products are out there we are receiveing logs with this incorrect WARN.
And also according to local tests on all production BDW here ULT or HALO we don't
need this force anymore. So let's clean this block for real.

v2: Fix LPT_LP WARNs to avoid wrong warns on BDW_ULT (By Jani).

Reference: https://bugs.freedesktop.org/attachment.cgi?id=110972

Cc: Jani Nikula &lt;jani.nikula@intel.com&gt;
Cc: Paulo Zanoni &lt;paulo.r.zanoni@intel.com&gt;
Cc: Xion Zhang &lt;xiong.y.zhang@intel.com&gt;
Cc: stable@vger.kernel.org
Signed-off-by: Rodrigo Vivi &lt;rodrigo.vivi@intel.com&gt;
Signed-off-by: Jani Nikula &lt;jani.nikula@intel.com&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>drm/i915: Only fence tiled region of object.</title>
<updated>2015-01-26T09:00:33+00:00</updated>
<author>
<name>Bob Paauwe</name>
<email>bob.j.paauwe@intel.com</email>
</author>
<published>2014-12-18T17:51:26+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=af1a7301c7cf8912dca03065d448c4437c5c239f'/>
<id>af1a7301c7cf8912dca03065d448c4437c5c239f</id>
<content type='text'>
When creating a fence for a tiled object, only fence the area that
makes up the actual tiles.  The object may be larger than the tiled
area and if we allow those extra addresses to be fenced, they'll
get converted to addresses beyond where the object is mapped. This
opens up the possiblity of writes beyond the end of object.

To prevent this, we adjust the size of the fence to only encompass
the area that makes up the actual tiles.  The extra space is considered
un-tiled and now behaves as if it was a linear object.

Testcase: igt/gem_tiled_fence_overflow
Reported-by: Dan Hettena &lt;danh@ghs.com&gt;
Signed-off-by: Bob Paauwe &lt;bob.j.paauwe@intel.com&gt;
Reviewed-by: Daniel Vetter &lt;daniel.vetter@ffwll.ch&gt;
Cc: stable@vger.kernel.org
Signed-off-by: Jani Nikula &lt;jani.nikula@intel.com&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
When creating a fence for a tiled object, only fence the area that
makes up the actual tiles.  The object may be larger than the tiled
area and if we allow those extra addresses to be fenced, they'll
get converted to addresses beyond where the object is mapped. This
opens up the possiblity of writes beyond the end of object.

To prevent this, we adjust the size of the fence to only encompass
the area that makes up the actual tiles.  The extra space is considered
un-tiled and now behaves as if it was a linear object.

Testcase: igt/gem_tiled_fence_overflow
Reported-by: Dan Hettena &lt;danh@ghs.com&gt;
Signed-off-by: Bob Paauwe &lt;bob.j.paauwe@intel.com&gt;
Reviewed-by: Daniel Vetter &lt;daniel.vetter@ffwll.ch&gt;
Cc: stable@vger.kernel.org
Signed-off-by: Jani Nikula &lt;jani.nikula@intel.com&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>drm/i915: fix inconsistent brightness after resume</title>
<updated>2015-01-26T09:00:33+00:00</updated>
<author>
<name>Jeremiah Mahler</name>
<email>jmmahler@gmail.com</email>
</author>
<published>2015-01-12T19:01:03+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=13f3fbe827d09e3182023c8c54058cbf97aa146e'/>
<id>13f3fbe827d09e3182023c8c54058cbf97aa146e</id>
<content type='text'>
commit 6dda730e55f412a6dfb181cae6784822ba463847
Author: Jani Nikula &lt;jani.nikula@intel.com&gt;
Date:   Tue Jun 24 18:27:40 2014 +0300

    drm/i915: respect the VBT minimum backlight brightness

introduced a bug which resulted in inconsistent brightness levels on
different machines. If a suspended was entered with the screen off some
machines would resume with the screen at minimum brightness and others
at maximum brightness.

The following commands can be used to produce this behavior.

  xset dpms force off
  sleep 1
  sudo systemctl suspend
  (resume ...)

The root cause of this problem is a comparison which checks to see if
the backlight level is zero when the panel is enabled.  If it is zero,
it is set to the maximum level.  Unfortunately, not all machines have a
minimum level of zero. On those machines the level is left at the
minimum instead of begin set to the maximum.

Fix the bug by updating the comparison to check for the minimum
backlight level instead of zero.  Also, expand the comparison for
the possible case when the level is less than the minimum.

Fixes: 6dda730e55f4 ("respect the VBT minimum backlight brightness")
Signed-off-by: Jeremiah Mahler &lt;jmmahler@gmail.com&gt;
Signed-off-by: Jani Nikula &lt;jani.nikula@intel.com&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
commit 6dda730e55f412a6dfb181cae6784822ba463847
Author: Jani Nikula &lt;jani.nikula@intel.com&gt;
Date:   Tue Jun 24 18:27:40 2014 +0300

    drm/i915: respect the VBT minimum backlight brightness

introduced a bug which resulted in inconsistent brightness levels on
different machines. If a suspended was entered with the screen off some
machines would resume with the screen at minimum brightness and others
at maximum brightness.

The following commands can be used to produce this behavior.

  xset dpms force off
  sleep 1
  sudo systemctl suspend
  (resume ...)

The root cause of this problem is a comparison which checks to see if
the backlight level is zero when the panel is enabled.  If it is zero,
it is set to the maximum level.  Unfortunately, not all machines have a
minimum level of zero. On those machines the level is left at the
minimum instead of begin set to the maximum.

Fix the bug by updating the comparison to check for the minimum
backlight level instead of zero.  Also, expand the comparison for
the possible case when the level is less than the minimum.

Fixes: 6dda730e55f4 ("respect the VBT minimum backlight brightness")
Signed-off-by: Jeremiah Mahler &lt;jmmahler@gmail.com&gt;
Signed-off-by: Jani Nikula &lt;jani.nikula@intel.com&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>drm/i915: Init PPGTT before context enable</title>
<updated>2015-01-26T09:00:32+00:00</updated>
<author>
<name>David Woodhouse</name>
<email>dwmw2@infradead.org</email>
</author>
<published>2015-01-20T17:21:42+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=f48a01651b1758550c4d3ee65ec726dfa0658780'/>
<id>f48a01651b1758550c4d3ee65ec726dfa0658780</id>
<content type='text'>
Commit 82460d972 ("drm/i915: Rework ppgtt init to no require an aliasing
ppgtt") introduced a regression on Broadwell, triggering the following
IOMMU fault at startup:

  vgaarb: device changed decodes: PCI:0000:00:02.0,olddecodes=io+mem,decodes=io+mem:owns=io+mem
  dmar: DRHD: handling fault status reg 2
  dmar: DMAR:[DMA Write] Request device [00:02.0] fault addr 880000
  DMAR:[fault reason 23] Unknown
  fbcon: inteldrmfb (fb0) is primary device

Further commentary from Daniel:

I sugggested this change to David after staring at the offending patch
for a while. I have no idea and theory whatsoever why this would upset
the gpu less than the other way round. But it seems to work. David
promised to chase hw people a bit more to get a more meaningful answer.

Wrt the comment that this deletes: I've done some digging and afaict
loading context before ppgtt enable was once required before our recent
restructuring of the context/ppgtt init code: Before that context sw
setup (i.e. allocating the default context) and hw setup was smashed
together.  Also the setup of the default context was the bit that
actually allocated the aliasing ppgtt structures. Which is the reason
for the context before ppgtt depency.

Or was, since with all the untangling there's no no real depency any
more (functional, who knows what the hw is doing), so the comment is
just stale.

Signed-off-by: David Woodhouse &lt;David.Woodhouse@intel.com&gt;
Cc: stable@vger.kernel.org
Reviewed-by: Daniel Vetter &lt;daniel.vetter@ffwll.ch&gt;
Signed-off-by: Jani Nikula &lt;jani.nikula@intel.com&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Commit 82460d972 ("drm/i915: Rework ppgtt init to no require an aliasing
ppgtt") introduced a regression on Broadwell, triggering the following
IOMMU fault at startup:

  vgaarb: device changed decodes: PCI:0000:00:02.0,olddecodes=io+mem,decodes=io+mem:owns=io+mem
  dmar: DRHD: handling fault status reg 2
  dmar: DMAR:[DMA Write] Request device [00:02.0] fault addr 880000
  DMAR:[fault reason 23] Unknown
  fbcon: inteldrmfb (fb0) is primary device

Further commentary from Daniel:

I sugggested this change to David after staring at the offending patch
for a while. I have no idea and theory whatsoever why this would upset
the gpu less than the other way round. But it seems to work. David
promised to chase hw people a bit more to get a more meaningful answer.

Wrt the comment that this deletes: I've done some digging and afaict
loading context before ppgtt enable was once required before our recent
restructuring of the context/ppgtt init code: Before that context sw
setup (i.e. allocating the default context) and hw setup was smashed
together.  Also the setup of the default context was the bit that
actually allocated the aliasing ppgtt structures. Which is the reason
for the context before ppgtt depency.

Or was, since with all the untangling there's no no real depency any
more (functional, who knows what the hw is doing), so the comment is
just stale.

Signed-off-by: David Woodhouse &lt;David.Woodhouse@intel.com&gt;
Cc: stable@vger.kernel.org
Reviewed-by: Daniel Vetter &lt;daniel.vetter@ffwll.ch&gt;
Signed-off-by: Jani Nikula &lt;jani.nikula@intel.com&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>drm/i915: Fix mutex-&gt;owner inspection race under DEBUG_MUTEXES</title>
<updated>2015-01-12T08:53:02+00:00</updated>
<author>
<name>Chris Wilson</name>
<email>chris@chris-wilson.co.uk</email>
</author>
<published>2015-01-02T09:47:10+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=226e5ae9e5f9108beb0bde4ac69f68fe6210fed9'/>
<id>226e5ae9e5f9108beb0bde4ac69f68fe6210fed9</id>
<content type='text'>
If CONFIG_DEBUG_MUTEXES is set, the mutex-&gt;owner field is only cleared
if the mutex debugging is enabled which introduces a race in our
mutex_is_locked_by() - i.e. we may inspect the old owner value before it
is acquired by the new task.

This is the root cause of this error:

 diff --git a/kernel/locking/mutex-debug.c b/kernel/locking/mutex-debug.c
 index 5cf6731..3ef3736 100644
 --- a/kernel/locking/mutex-debug.c
 +++ b/kernel/locking/mutex-debug.c
 @@ -80,13 +80,13 @@ void debug_mutex_unlock(struct mutex *lock)
 			DEBUG_LOCKS_WARN_ON(lock-&gt;owner != current);

 		DEBUG_LOCKS_WARN_ON(!lock-&gt;wait_list.prev &amp;&amp; !lock-&gt;wait_list.next);
 -		mutex_clear_owner(lock);
 	}

 	/*
 	 * __mutex_slowpath_needs_to_unlock() is explicitly 0 for debug
 	 * mutexes so that we can do it here after we've verified state.
 	 */
 +	mutex_clear_owner(lock);
 	atomic_set(&amp;lock-&gt;count, 1);
  }

Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=87955
Signed-off-by: Chris Wilson &lt;chris@chris-wilson.co.uk&gt;
Cc: stable@vger.kernel.org
Reviewed-by: Daniel Vetter &lt;daniel.vetter@ffwll.ch&gt;
Signed-off-by: Jani Nikula &lt;jani.nikula@intel.com&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
If CONFIG_DEBUG_MUTEXES is set, the mutex-&gt;owner field is only cleared
if the mutex debugging is enabled which introduces a race in our
mutex_is_locked_by() - i.e. we may inspect the old owner value before it
is acquired by the new task.

This is the root cause of this error:

 diff --git a/kernel/locking/mutex-debug.c b/kernel/locking/mutex-debug.c
 index 5cf6731..3ef3736 100644
 --- a/kernel/locking/mutex-debug.c
 +++ b/kernel/locking/mutex-debug.c
 @@ -80,13 +80,13 @@ void debug_mutex_unlock(struct mutex *lock)
 			DEBUG_LOCKS_WARN_ON(lock-&gt;owner != current);

 		DEBUG_LOCKS_WARN_ON(!lock-&gt;wait_list.prev &amp;&amp; !lock-&gt;wait_list.next);
 -		mutex_clear_owner(lock);
 	}

 	/*
 	 * __mutex_slowpath_needs_to_unlock() is explicitly 0 for debug
 	 * mutexes so that we can do it here after we've verified state.
 	 */
 +	mutex_clear_owner(lock);
 	atomic_set(&amp;lock-&gt;count, 1);
  }

Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=87955
Signed-off-by: Chris Wilson &lt;chris@chris-wilson.co.uk&gt;
Cc: stable@vger.kernel.org
Reviewed-by: Daniel Vetter &lt;daniel.vetter@ffwll.ch&gt;
Signed-off-by: Jani Nikula &lt;jani.nikula@intel.com&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>drm/i915: Ban Haswell from using RCS flips</title>
<updated>2015-01-12T08:52:42+00:00</updated>
<author>
<name>Chris Wilson</name>
<email>chris@chris-wilson.co.uk</email>
</author>
<published>2014-12-27T09:48:28+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=48bf5b2d00bfeb681f6500c626189c7cd2c964d2'/>
<id>48bf5b2d00bfeb681f6500c626189c7cd2c964d2</id>
<content type='text'>
Like Ivybridge, we have reports that we get random hangs when flipping
with multiple pipes. Extend

commit 2a92d5bca1999b69c78f3c3e97b5484985b094b9
Author: Chris Wilson &lt;chris@chris-wilson.co.uk&gt;
Date:   Tue Jul 8 10:40:29 2014 +0100

    drm/i915: Disable RCS flips on Ivybridge

to also apply to Haswell.

Reported-and-tested-by: Scott Tsai &lt;scottt.tw@gmail.com&gt;
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=87759
Signed-off-by: Chris Wilson &lt;chris@chris-wilson.co.uk&gt;
Reviewed-by: Daniel Vetter &lt;daniel.vetter@ffwll.ch&gt;
Cc: stable@vger.kernel.org # 2a92d5bca199 drm/i915: Disable RCS flips on Ivybridge
Cc: stable@vger.kernel.org
Signed-off-by: Jani Nikula &lt;jani.nikula@intel.com&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Like Ivybridge, we have reports that we get random hangs when flipping
with multiple pipes. Extend

commit 2a92d5bca1999b69c78f3c3e97b5484985b094b9
Author: Chris Wilson &lt;chris@chris-wilson.co.uk&gt;
Date:   Tue Jul 8 10:40:29 2014 +0100

    drm/i915: Disable RCS flips on Ivybridge

to also apply to Haswell.

Reported-and-tested-by: Scott Tsai &lt;scottt.tw@gmail.com&gt;
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=87759
Signed-off-by: Chris Wilson &lt;chris@chris-wilson.co.uk&gt;
Reviewed-by: Daniel Vetter &lt;daniel.vetter@ffwll.ch&gt;
Cc: stable@vger.kernel.org # 2a92d5bca199 drm/i915: Disable RCS flips on Ivybridge
Cc: stable@vger.kernel.org
Signed-off-by: Jani Nikula &lt;jani.nikula@intel.com&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>drm/i915: vlv: sanitize RPS interrupt mask during GPU idling</title>
<updated>2015-01-12T08:52:41+00:00</updated>
<author>
<name>Imre Deak</name>
<email>imre.deak@intel.com</email>
</author>
<published>2014-12-19T17:33:27+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=f24eeb191229b040deb3e813913e06a4316c6d3f'/>
<id>f24eeb191229b040deb3e813913e06a4316c6d3f</id>
<content type='text'>
We apply the RPS interrupt workaround on VLV everywhere except when
writing the mask directly during idling the GPU. For consistency do this
also there.

While at it also extend the code comment about affected platforms.
I couldn't reproduce the issue on VLV fixed by this workaround, by
removing the workaround from everywhere, while it's 100% reproducible on
SNB using igt/gem_reset_stats/ban-ctx-render. So also add a note that
it hasn't been verified if the workaround really applies to VLV/CHV.

Suggested-by: Daniel Vetter &lt;daniel.vetter@ffwll.ch&gt;
Signed-off-by: Imre Deak &lt;imre.deak@intel.com&gt;
Reviewed-by: Daniel Vetter &lt;daniel.vetter@ffwll.ch&gt;
Signed-off-by: Jani Nikula &lt;jani.nikula@intel.com&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
We apply the RPS interrupt workaround on VLV everywhere except when
writing the mask directly during idling the GPU. For consistency do this
also there.

While at it also extend the code comment about affected platforms.
I couldn't reproduce the issue on VLV fixed by this workaround, by
removing the workaround from everywhere, while it's 100% reproducible on
SNB using igt/gem_reset_stats/ban-ctx-render. So also add a note that
it hasn't been verified if the workaround really applies to VLV/CHV.

Suggested-by: Daniel Vetter &lt;daniel.vetter@ffwll.ch&gt;
Signed-off-by: Imre Deak &lt;imre.deak@intel.com&gt;
Reviewed-by: Daniel Vetter &lt;daniel.vetter@ffwll.ch&gt;
Signed-off-by: Jani Nikula &lt;jani.nikula@intel.com&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>drm/i915: fix HW lockup due to missing RPS IRQ workaround on GEN6</title>
<updated>2015-01-12T08:52:41+00:00</updated>
<author>
<name>Imre Deak</name>
<email>imre.deak@intel.com</email>
</author>
<published>2014-12-19T17:33:26+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=59d02a1f45beb1b6f4ef83a47feb264cb3577725'/>
<id>59d02a1f45beb1b6f4ef83a47feb264cb3577725</id>
<content type='text'>
In

commit dbea3cea69508e9d548ed4a6be13de35492e5d15
Author: Imre Deak &lt;imre.deak@intel.com&gt;
Date:   Mon Dec 15 18:59:28 2014 +0200

    drm/i915: sanitize RPS resetting during GPU reset

we disable RPS interrupts during GPU resetting, but don't apply the
necessary GEN6 HW workaround. This leads to a HW lockup during a
subsequent "looping batchbuffer" workload. This is triggered by the
testcase that submits exactly this kind of workload after a simulated
GPU reset. I'm not sure how likely the bug would have triggered
otherwise, since we would have applied the workaround anyway shortly
after the GPU reset, when enabling GT powersaving from the deferred
work.

This may also fix unrelated issues, since during driver loading /
suspending we also disable RPS interrupts and so we also had a short
window during the rest of the loading / resuming where a similar
workload could run without the workaround applied.

v2:
- separate the fix to route RPS interrupts to the CPU on GEN9 too
  to a separate patch (Daniel)

Bisected-by: Ander Conselvan de Oliveira &lt;ander.conselvan.de.oliveira@intel.com&gt;
Testcase: igt/gem_reset_stats/ban-ctx-render
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=87429
Signed-off-by: Imre Deak &lt;imre.deak@intel.com&gt;
Reviewed-by: Daniel Vetter &lt;daniel.vetter@ffwll.ch&gt;
Signed-off-by: Jani Nikula &lt;jani.nikula@intel.com&gt;
</content>
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<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
In

commit dbea3cea69508e9d548ed4a6be13de35492e5d15
Author: Imre Deak &lt;imre.deak@intel.com&gt;
Date:   Mon Dec 15 18:59:28 2014 +0200

    drm/i915: sanitize RPS resetting during GPU reset

we disable RPS interrupts during GPU resetting, but don't apply the
necessary GEN6 HW workaround. This leads to a HW lockup during a
subsequent "looping batchbuffer" workload. This is triggered by the
testcase that submits exactly this kind of workload after a simulated
GPU reset. I'm not sure how likely the bug would have triggered
otherwise, since we would have applied the workaround anyway shortly
after the GPU reset, when enabling GT powersaving from the deferred
work.

This may also fix unrelated issues, since during driver loading /
suspending we also disable RPS interrupts and so we also had a short
window during the rest of the loading / resuming where a similar
workload could run without the workaround applied.

v2:
- separate the fix to route RPS interrupts to the CPU on GEN9 too
  to a separate patch (Daniel)

Bisected-by: Ander Conselvan de Oliveira &lt;ander.conselvan.de.oliveira@intel.com&gt;
Testcase: igt/gem_reset_stats/ban-ctx-render
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=87429
Signed-off-by: Imre Deak &lt;imre.deak@intel.com&gt;
Reviewed-by: Daniel Vetter &lt;daniel.vetter@ffwll.ch&gt;
Signed-off-by: Jani Nikula &lt;jani.nikula@intel.com&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>drm/i915: gen9: fix RPS interrupt routing to CPU vs. GT</title>
<updated>2015-01-12T08:52:41+00:00</updated>
<author>
<name>Imre Deak</name>
<email>imre.deak@intel.com</email>
</author>
<published>2014-12-19T17:33:25+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=63a3451641ec2e129dfe80044e3c96bc9f0bb690'/>
<id>63a3451641ec2e129dfe80044e3c96bc9f0bb690</id>
<content type='text'>
GEN8+ HW has the option to route PM interrupts to either the CPU or to
GT. For GEN8 this was already set correctly to routing to CPU, but not
for GEN9, so fix this. Note that when disabling RPS interrupts this was
set already correctly, though in that case it didn't matter much except
for the possibility of spurious interrupts.

Signed-off-by: Imre Deak &lt;imre.deak@intel.com&gt;
Reviewed-by: Daniel Vetter &lt;daniel.vetter@ffwll.ch&gt;
Signed-off-by: Jani Nikula &lt;jani.nikula@intel.com&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
GEN8+ HW has the option to route PM interrupts to either the CPU or to
GT. For GEN8 this was already set correctly to routing to CPU, but not
for GEN9, so fix this. Note that when disabling RPS interrupts this was
set already correctly, though in that case it didn't matter much except
for the possibility of spurious interrupts.

Signed-off-by: Imre Deak &lt;imre.deak@intel.com&gt;
Reviewed-by: Daniel Vetter &lt;daniel.vetter@ffwll.ch&gt;
Signed-off-by: Jani Nikula &lt;jani.nikula@intel.com&gt;
</pre>
</div>
</content>
</entry>
</feed>
