path: root/Documentation/gpu
diff options
authorMaxime Ripard <>2021-03-16 09:06:23 +0100
committerMaxime Ripard <>2021-03-16 09:06:23 +0100
commitf8bade6c9a6213c2c5ba6e5bf32415ecab6e41e5 (patch)
tree474c8fb8df9797b6e0d1e562b389f575c24afc50 /Documentation/gpu
parentccf953d8f3d68e85e577e843fdcde8872b0a9769 (diff)
parent51c3b916a4d7e24b4918925965867fdd9bd8dd59 (diff)
Merge drm/drm-next into drm-misc-next
Noralf needs some patches in 5.12-rc3, and we've been delaying the 5.12 merge due to the swap issue so it looks like a good time. Signed-off-by: Maxime Ripard <>
Diffstat (limited to 'Documentation/gpu')
2 files changed, 23 insertions, 2 deletions
diff --git a/Documentation/gpu/i915.rst b/Documentation/gpu/i915.rst
index 20868f3d0123..486c720f3890 100644
--- a/Documentation/gpu/i915.rst
+++ b/Documentation/gpu/i915.rst
@@ -428,7 +428,7 @@ User Batchbuffer Execution
Logical Rings, Logical Ring Contexts and Execlists
-.. kernel-doc:: drivers/gpu/drm/i915/gt/intel_lrc.c
+.. kernel-doc:: drivers/gpu/drm/i915/gt/intel_execlists_submission.c
:doc: Logical Rings, Logical Ring Contexts and Execlists
Global GTT views
diff --git a/Documentation/gpu/todo.rst b/Documentation/gpu/todo.rst
index 62475d38c4ab..7ff9fac10d8b 100644
--- a/Documentation/gpu/todo.rst
+++ b/Documentation/gpu/todo.rst
@@ -571,6 +571,27 @@ Contact: Daniel Vetter
Level: Intermediate
+Remove automatic page mapping from dma-buf importing
+When importing dma-bufs, the dma-buf and PRIME frameworks automatically map
+imported pages into the importer's DMA area. drm_gem_prime_fd_to_handle() and
+drm_gem_prime_handle_to_fd() require that importers call dma_buf_attach()
+even if they never do actual device DMA, but only CPU access through
+dma_buf_vmap(). This is a problem for USB devices, which do not support DMA
+To fix the issue, automatic page mappings should be removed from the
+buffer-sharing code. Fixing this is a bit more involved, since the import/export
+cache is also tied to &drm_gem_object.import_attach. Meanwhile we paper over
+this problem for USB devices by fishing out the USB host controller device, as
+long as that supports DMA. Otherwise importing can still needlessly fail.
+Contact: Thomas Zimmermann <>, Daniel Vetter
+Level: Advanced
Better Testing
@@ -644,7 +665,7 @@ for fbdev.
- [RFC PATCH v2 00/13] Kernel based bootsplash
Contact: Sam Ravnborg