Register 0x907c needs to be set for driver boot. http://dt.igk.intel.com/wa_database/DetailsView/Show?wa_name_id=891
Patch merged to dinq: commit b4ae3f22d238617ca11610b29fde16cf8c0bc6e0 Author: Jesse Barnes <jbarnes@virtuousgeek.org> Date: Thu Jun 14 11:04:48 2012 -0700 drm/i915: load boot context at driver init time
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