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  1. 04 6月, 2014 1 次提交
    • D
      drm: Split connection_mutex out of mode_config.mutex (v3) · 6e9f798d
      由 Daniel Vetter 提交于 
      After the split-out of crtc locks from the big mode_config.mutex
there's still two major areas it protects:
- Various connector probe states, like connector->status, EDID
  properties, probed mode lists and similar information.
- The links from connector->encoder and encoder->crtc and other
  modeset-relevant connector state (e.g. properties which control the
  panel fitter).

The later is used by modeset operations. But they don't really care
about the former since it's allowed to e.g. enable a disconnected VGA
output or with a mode not in the probed list.

Thus far this hasn't been a problem, but for the atomic modeset
conversion Rob Clark needs to convert all modeset relevant locks into
w/w locks. This is required because the order of acquisition is
determined by how userspace supplies the atomic modeset data. This has
run into troubles in the detect path since the i915 load detect code
needs _both_ protections offered by the mode_config.mutex: It updates
probe state and it needs to change the modeset configuration to enable
the temporary load detect pipe.

The big deal here is that for the probe/detect users of this lock a
plain mutex fits best, but for atomic modesets we really want a w/w
mutex. To fix this lets split out a new connection_mutex lock for the
modeset relevant parts.

For simplicity I've decided to only add one additional lock for all
connector/encoder links and modeset configuration states. We have
piles of different modeset objects in addition to those (like bridges
or panels), so adding per-object locks would be much more effort.

Also, we're guaranteed (at least for now) to do a full modeset if we
need to acquire this lock. Which means that fine-grained locking is
fairly irrelevant compared to the amount of time the full modeset will
take.

I've done a full audit, and there's just a few things that justify
special focus:
- Locking in drm_sysfs.c is almost completely absent. We should
  sprinkle mode_config.connection_mutex over this file a bit, but
  since it already lacks mode_config.mutex this patch wont make the
  situation any worse. This is material for a follow-up patch.

- omap has a omap_framebuffer_flush function which walks the
  connector->encoder->crtc links and is called from many contexts.
  Some look like they don't acquire mode_config.mutex, so this is
  already racy. Again fixing this is material for a separate patch.

- The radeon hot_plug function to retrain DP links looks at
  connector->dpms. Currently this happens without any locking, so is
  already racy. I think radeon_hotplug_work_func should gain
  mutex_lock/unlock calls for the mode_config.connection_mutex.

- Same applies to i915's intel_dp_hot_plug. But again, this is already
  racy.

- i915 load_detect code needs to acquire this lock. Which means the
  w/w dance due to Rob's work will be nicely contained to _just_ this
  function.

I've added fixme comments everywhere where it looks suspicious but in
the sysfs code. After a quick irc discussion with Dave Airlie it
sounds like the lack of locking in there is due to sysfs cleanup fun
at module unload.

v1: original (only compile tested)

v2: missing mutex_init(), etc (from Rob Clark)

v3: i915 needs more care in the conversion:
- Protect the edp pp logic with the connection_mutex.
- Use connection_mutex in the backlight code due to
  get_pipe_from_connector.
- Use drm_modeset_lock_all in suspend/resume paths.
- Update lock checks in the overlay code.

Cc: Alex Deucher <alexdeucher@gmail.com>
Cc: Rob Clark <robdclark@gmail.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>
Reviewed-by: NRob Clark <robdclark@gmail.com>
      6e9f798d
  3. 05 2月, 2014 1 次提交
  5. 22 1月, 2014 1 次提交
  7. 07 12月, 2013 1 次提交
  9. 04 12月, 2013 1 次提交
  11. 15 11月, 2013 1 次提交
  13. 13 11月, 2013 1 次提交
  15. 09 11月, 2013 1 次提交
  17. 07 11月, 2013 2 次提交
  19. 14 10月, 2013 1 次提交
  21. 12 10月, 2013 1 次提交
    • P
      drm/i915: increase the SWSCI DSLP default timeout to 50ms · 4994aa8c
      由 Paulo Zanoni 提交于 
      The spec says the default timeout should be 2ms, but on my machine
this doesn't seem to be enough. Sometimes it works, sometimes I get
these messages when booting:
  - SWSCI request timed out
  - SWSCI request already in progress

And my guess is that the "already in progress" message is because the
first one is still happening.

I did some experiments on my machine (that has CONFIG_HZ=1000) and the
wait_for function usually takes 4-6 jiffies to finish, but I've seen
up to 9. So increase the timeout to 50ms. We only expect to wait for
the actual amount of time the operation takes, so even a huge timeout
shouldn't delay us more than what the hardware actually requires.

Cc: Jani Nikula <jani.nikula@intel.com>
Signed-off-by: NPaulo Zanoni <paulo.r.zanoni@intel.com>
Reviewed-by: NJani Nikula <jani.nikula@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>
      4994aa8c
  23. 18 9月, 2013 1 次提交
    • P
      drm/i915: check for more ASLC interrupts · 507c1a45
      由 Paulo Zanoni 提交于 
      Sometimes I see the "non asle set request??" message on my Haswell
machine, so I decided to get the spec and see if some bits are missing
from the mask. We do have some bits missing from the mask, so this
patch adds them, and the corresponding code to print "unsupported"
messages just like we do with the other bits we don't support.

But I still see the "non asle set request??" message on my machine :(

Also use the proper ASLC name to indicate the registers we're talking
about.

v2: - Properly set the new FAILED bits
    - Rename the old FAILED bits
    - Print everything we don't support
Signed-off-by: NPaulo Zanoni <paulo.r.zanoni@intel.com>
Reviewed-by: NJani Nikula <jani.nikula@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>
      507c1a45
  25. 13 9月, 2013 1 次提交
  27. 06 9月, 2013 1 次提交
    • J
      drm/i915: try not to lose backlight CBLV precision · cac6a5ae
      由 Jani Nikula 提交于 
      ACPI has _BCM and _BQC methods to set and query the backlight
brightness, respectively. The ACPI opregion has variables BCLP and CBLV
to hold the requested and current backlight brightness, respectively.

The BCLP variable has range 0..255 while the others have range
0..100. This means the _BCM method has to scale the brightness for BCLP,
and the gfx driver has to scale the requested value back for CBLV. If
the _BQC method uses the CBLV variable (apparently some implementations
do, some don't) for current backlight level reporting, there's room for
rounding errors.

Use DIV_ROUND_UP for scaling back to CBLV to get back to the same values
that were passed to _BCM, presuming the _BCM simply uses bclp = (in *
255) / 100 for scaling to BCLP.

Reference: https://gist.github.com/aaronlu/6314920Reported-by: NAaron Lu <aaron.lu@intel.com>
Signed-off-by: NJani Nikula <jani.nikula@intel.com>
Reviewed-by: NAaron Lu <aaron.lu@intel.com>
Cc: stable@vger.kernel.org
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>
      cac6a5ae
  29. 04 9月, 2013 3 次提交
  31. 01 7月, 2013 1 次提交
  33. 06 6月, 2013 1 次提交
  35. 30 4月, 2013 4 次提交
  37. 25 4月, 2013 4 次提交
  39. 25 3月, 2013 1 次提交
  41. 01 2月, 2013 1 次提交
  43. 03 10月, 2012 1 次提交
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  51. 19 3月, 2012 1 次提交
  53. 20 9月, 2011 1 次提交
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  57. 14 7月, 2011 1 次提交
  59. 25 2月, 2011 1 次提交
  61. 25 1月, 2011 1 次提交