Daniel Vetter 2406e63c32 drm/i915: hold forcewake around ring hw init ... commit b7884eb45e upstream. Empirical evidence suggests that we need to: On at least one ivb machine when running the hangman i-g-t test, the rings don't properly initialize properly - the RING_START registers seems to be stuck at all zeros. Holding forcewake around this register init sequences makes chip reset reliable again. Note that this is not the first such issue: commit f01db988ef Author: Sean Paul <seanpaul@chromium.org> Date: Fri Mar 16 12:43:22 2012 -0400 drm/i915: Add wait_for in init_ring_common added delay loops to make RING_START and RING_CTL initialization reliable on the blt ring at boot-up. So I guess it won't hurt if we do this unconditionally for all force_wake needing gpus. To avoid copy&pasting of the HAS_FORCE_WAKE check I've added a new intel_info bit for that. v2: Fixup missing commas in static struct and properly handling the error case in init_ring_common, both noticed by Jani Nikula. Reported-and-tested-by: Yang Guang <guang.a.yang@intel.com> Reviewed-by: Eugeni Dodonov <eugeni.dodonov@intel.com> Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=50522 Signed-Off-by: Daniel Vetter <daniel.vetter@ffwll.ch> [bwh: Backported to 3.2: - drop changes to Haswell device information - NEEDS_FORCE_WAKE didn't refer to Valley View anyway] Signed-off-by: Ben Hutchings <ben@decadent.org.uk> [jcristau: further context adjustments for 3.4] Signed-off-by: Julien Cristau <jcristau@debian.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>		2013-01-17 08:51:07 -08:00
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drm	drm/i915: hold forcewake around ring hw init	2013-01-17 08:51:07 -08:00
stub	i915: select VIDEO_OUTPUT_CONTROL for ACPI_VIDEO	2011-04-13 09:10:25 +10:00
vga	drivers/gpu/vga/vgaarb.c: add missing kfree	2011-11-22 20:21:10 +00:00
Makefile	gpu: Add Intel GMA500(Poulsbo) Stub Driver	2010-10-26 11:00:13 +10:00