diff mbox series

[07/12] drm/i915: Fix PTE decode during initial plane readout

Message ID 20231213004237.20375-8-ville.syrjala@linux.intel.com (mailing list archive)
State New, archived
Headers show
Series drm/i915: (stolen) memory region related fixes | expand

Commit Message

Ville Syrjälä Dec. 13, 2023, 12:42 a.m. UTC 
From: Ville Syrjälä <ville.syrjala@linux.intel.com>

When multiple pipes are enabled by the BIOS we try to read out each
in turn. But we do the readout for the second only after the inherited
vma for the first has been rebound into its original place (and thus
the PTEs have been rewritten). Unlike the BIOS we set some high caching
bits in the PTE on MTL which confuses the readout for the second plane.
Filter out the non-address bits from the PTE value appropriately to
fix this.

I suppose it might also be possible that the BIOS would already set
some caching bits as well, in which case we'd run into this same
issue already for the first plane.

TODO:
- should abstract the PTE decoding to avoid details leaking all over
- should probably do the readout for all the planes before
  we touch anything (including the PTEs) so that we truly read
  out the BIOS state

Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
---
 drivers/gpu/drm/i915/display/intel_plane_initial.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)
diff mbox series

Patch

diff --git a/drivers/gpu/drm/i915/display/intel_plane_initial.c b/drivers/gpu/drm/i915/display/intel_plane_initial.c
index a55c09cbd0e4..ffc92b18fcf5 100644
--- a/drivers/gpu/drm/i915/display/intel_plane_initial.c
+++ b/drivers/gpu/drm/i915/display/intel_plane_initial.c
@@ -72,7 +72,7 @@  initial_plane_vma(struct drm_i915_private *i915,
 			return NULL;
 		}
 
-		phys_base = pte & I915_GTT_PAGE_MASK;
+		phys_base = pte & GEN12_GGTT_PTE_ADDR_MASK;
 		mem = i915->mm.regions[INTEL_REGION_LMEM_0];
 
 		/*