drm/i915: grab force_wake when restoring LCPLL

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If LCPLL is disabled, there's a chance we might be in package C8 state
or deeper, and we'll get a hard hang when restoring LCPLL (also, a red
led lights up on my motherboard). So grab the force_wake, which will
get us out of RC6 and, as a consequence, out of PC8+ (since we need
RC6 to get into PC8+).

Note: Discussions with hw designers are still ongoing what exactly
goes boom here. But I think we can go ahead and just merge this little
hack for now until it's clear what we actually need.

Signed-off-by: Paulo Zanoni <paulo.r.zanoni@intel.com>
[danvet: Add small note about the current state of the discussion
around this hack.]
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>

...

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Paulo Zanoni 2013-08-19 13:18:07 -03:00 • committed by Daniel Vetter

parent 3414caf634

commit 215733fadb

1 changed files with 6 additions and 0 deletions

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drivers/gpu/drm/i915/intel_display.c

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