From bf7cda9a0101c4a149aa5846306df9d21dd5cc2b Mon Sep 17 00:00:00 2001 From: Chris Wilson Date: Tue, 18 Mar 2014 14:50:50 +0200 Subject: drm/i915: Disable stolen memory when DMAR is active commit 0f4706d2740f2a221cd502922b22e522009041d9 upstream. We have reports of heavy screen corruption if we try to use the stolen memory reserved by the BIOS whilst the DMA-Remapper is active. This quirk may be only specific to a few machines or BIOSes, but first lets apply the big hammer and always disable use of stolen memory when DMAR is active. v2 by Jani: Rebase on -fixes, only look at intel_iommu_gfx_mapped. Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=68535 Signed-off-by: Chris Wilson Reviewed-by: Daniel Vetter Signed-off-by: Jani Nikula Signed-off-by: Jiri Slaby --- drivers/gpu/drm/i915/i915_gem_stolen.c | 7 +++++++ 1 file changed, 7 insertions(+) (limited to 'drivers') diff --git a/drivers/gpu/drm/i915/i915_gem_stolen.c b/drivers/gpu/drm/i915/i915_gem_stolen.c index fe4a7d16e261..c077df094ae5 100644 --- a/drivers/gpu/drm/i915/i915_gem_stolen.c +++ b/drivers/gpu/drm/i915/i915_gem_stolen.c @@ -201,6 +201,13 @@ int i915_gem_init_stolen(struct drm_device *dev) struct drm_i915_private *dev_priv = dev->dev_private; int bios_reserved = 0; +#ifdef CONFIG_INTEL_IOMMU + if (intel_iommu_gfx_mapped) { + DRM_INFO("DMAR active, disabling use of stolen memory\n"); + return 0; + } +#endif + if (dev_priv->gtt.stolen_size == 0) return 0; -- cgit v1.2.3