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path: root/drivers/gpu/drm/i915/i915_gem_stolen.c
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Diffstat (limited to 'drivers/gpu/drm/i915/i915_gem_stolen.c')
-rw-r--r--drivers/gpu/drm/i915/i915_gem_stolen.c44
1 files changed, 44 insertions, 0 deletions
diff --git a/drivers/gpu/drm/i915/i915_gem_stolen.c b/drivers/gpu/drm/i915/i915_gem_stolen.c
index 62ef55ba061c..7465ab0fd396 100644
--- a/drivers/gpu/drm/i915/i915_gem_stolen.c
+++ b/drivers/gpu/drm/i915/i915_gem_stolen.c
@@ -74,6 +74,50 @@ static unsigned long i915_stolen_to_physical(struct drm_device *dev)
if (base == 0)
return 0;
+ /* make sure we don't clobber the GTT if it's within stolen memory */
+ if (INTEL_INFO(dev)->gen <= 4 && !IS_G33(dev) && !IS_G4X(dev)) {
+ struct {
+ u32 start, end;
+ } stolen[2] = {
+ { .start = base, .end = base + dev_priv->gtt.stolen_size, },
+ { .start = base, .end = base + dev_priv->gtt.stolen_size, },
+ };
+ u64 gtt_start, gtt_end;
+
+ gtt_start = I915_READ(PGTBL_CTL);
+ if (IS_GEN4(dev))
+ gtt_start = (gtt_start & PGTBL_ADDRESS_LO_MASK) |
+ (gtt_start & PGTBL_ADDRESS_HI_MASK) << 28;
+ else
+ gtt_start &= PGTBL_ADDRESS_LO_MASK;
+ gtt_end = gtt_start + gtt_total_entries(dev_priv->gtt) * 4;
+
+ if (gtt_start >= stolen[0].start && gtt_start < stolen[0].end)
+ stolen[0].end = gtt_start;
+ if (gtt_end > stolen[1].start && gtt_end <= stolen[1].end)
+ stolen[1].start = gtt_end;
+
+ /* pick the larger of the two chunks */
+ if (stolen[0].end - stolen[0].start >
+ stolen[1].end - stolen[1].start) {
+ base = stolen[0].start;
+ dev_priv->gtt.stolen_size = stolen[0].end - stolen[0].start;
+ } else {
+ base = stolen[1].start;
+ dev_priv->gtt.stolen_size = stolen[1].end - stolen[1].start;
+ }
+
+ if (stolen[0].start != stolen[1].start ||
+ stolen[0].end != stolen[1].end) {
+ DRM_DEBUG_KMS("GTT within stolen memory at 0x%llx-0x%llx\n",
+ (unsigned long long) gtt_start,
+ (unsigned long long) gtt_end - 1);
+ DRM_DEBUG_KMS("Stolen memory adjusted to 0x%x-0x%x\n",
+ base, base + (u32) dev_priv->gtt.stolen_size - 1);
+ }
+ }
+
+
/* Verify that nothing else uses this physical address. Stolen
* memory should be reserved by the BIOS and hidden from the
* kernel. So if the region is already marked as busy, something