Even with the cumulative set of ilk w/a, rc6 is demonstrably still failing and causing GPU hangs as found by Peter Wu. So we need to disable it again until it is stable. This reverts commit 456470eb583f063ee84c6818251e638598be0fb8 Author: Daniel Vetter <daniel.vetter at ffwll.ch> Date: Wed Aug 8 23:35:40 2012 +0200 drm/i915: enable rc6 on ilk again and the follow-on commit cd7988eea561a70a4f98e431c1395f913672d626 Author: Daniel Vetter <daniel.vetter at ffwll.ch> Date: Sun Aug 26 20:33:18 2012 +0200 drm/i915: disable rc6 on ilk when vt-d is enabled Reported-by: Peter Wu <lekensteyn at gmail.com> References: https://bugs.freedesktop.org/show_bug.cgi?id=55984 Signed-off-by: Chris Wilson <chris at chris-wilson.co.uk> --- drivers/gpu/drm/i915/intel_pm.c | 12 +++--------- 1 file changed, 3 insertions(+), 9 deletions(-) diff --git a/drivers/gpu/drm/i915/intel_pm.c b/drivers/gpu/drm/i915/intel_pm.c index 4018ef4..2bda628 100644 --- a/drivers/gpu/drm/i915/intel_pm.c +++ b/drivers/gpu/drm/i915/intel_pm.c @@ -2381,15 +2381,9 @@ int intel_enable_rc6(const struct drm_device *dev) if (i915_enable_rc6 >= 0) return i915_enable_rc6; - if (INTEL_INFO(dev)->gen == 5) { -#ifdef CONFIG_INTEL_IOMMU - /* Disable rc6 on ilk if VT-d is on. */ - if (intel_iommu_gfx_mapped) - return false; -#endif - DRM_DEBUG_DRIVER("Ironlake: only RC6 available\n"); - return INTEL_RC6_ENABLE; - } + /* Disable RC6 on Ironlake */ + if (INTEL_INFO(dev)->gen == 5) + return 0; if (IS_HASWELL(dev)) { DRM_DEBUG_DRIVER("Haswell: only RC6 available\n"); -- 1.7.10.4