Merge branch 'nfsd-next' of git://linux-nfs.org/~bfields/linux

[~andy/linux] / drivers / gpu / drm / i915 / i915_gem_stolen.c

diff --git a/drivers/gpu/drm/i915/i915_gem_stolen.c b/drivers/gpu/drm/i915/i915_gem_stolen.c
index 1a24e84f231578ae772d40ad75adda4c356b8d68..28d24caa49f3f7720c63e208c4831c79f5433d8d 100644 (file)
--- a/drivers/gpu/drm/i915/i915_gem_stolen.c
+++ b/drivers/gpu/drm/i915/i915_gem_stolen.c
@@ -82,9 +82,22 @@ static unsigned long i915_stolen_to_physical(struct drm_device *dev)
        r = devm_request_mem_region(dev->dev, base, dev_priv->gtt.stolen_size,
                                    "Graphics Stolen Memory");
        if (r == NULL) {
-               DRM_ERROR("conflict detected with stolen region: [0x%08x - 0x%08x]\n",
-                         base, base + (uint32_t)dev_priv->gtt.stolen_size);
-               base = 0;
+               /*
+                * One more attempt but this time requesting region from
+                * base + 1, as we have seen that this resolves the region
+                * conflict with the PCI Bus.
+                * This is a BIOS w/a: Some BIOS wrap stolen in the root
+                * PCI bus, but have an off-by-one error. Hence retry the
+                * reservation starting from 1 instead of 0.
+                */
+               r = devm_request_mem_region(dev->dev, base + 1,
+                                           dev_priv->gtt.stolen_size - 1,
+                                           "Graphics Stolen Memory");
+               if (r == NULL) {
+                       DRM_ERROR("conflict detected with stolen region: [0x%08x - 0x%08x]\n",
+                                 base, base + (uint32_t)dev_priv->gtt.stolen_size);
+                       base = 0;
+               }
        }
 
        return base;
@@ -201,6 +214,13 @@ 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;