Documentation: media: move Memory Consistency Flags
Commit Message
The documentation of the Memory Consistency Flags was part of the struct
v4l2_buffer documentation, but that struct doesn't use those flags. Instead
it is used by VIDIOC_CREATE_BUFS and VIDIOC_REQBUFS. Move the documentation
from buffer.rst to vidioc-reqbufs.rst which is where it belongs.
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
---
@@ -694,41 +694,6 @@ enum v4l2_memory
- 4
- The buffer is used for :ref:`DMA shared buffer <dmabuf>` I/O.
-.. _memory-flags:
-
-Memory Consistency Flags
-------------------------
-
-.. raw:: latex
-
- \small
-
-.. tabularcolumns:: |p{7.0cm}|p{2.1cm}|p{8.4cm}|
-
-.. cssclass:: longtable
-
-.. flat-table::
- :header-rows: 0
- :stub-columns: 0
- :widths: 3 1 4
-
- * .. _`V4L2-MEMORY-FLAG-NON-COHERENT`:
-
- - ``V4L2_MEMORY_FLAG_NON_COHERENT``
- - 0x00000001
- - A buffer is allocated either in coherent (it will be automatically
- coherent between the CPU and the bus) or non-coherent memory. The
- latter can provide performance gains, for instance the CPU cache
- sync/flush operations can be avoided if the buffer is accessed by the
- corresponding device only and the CPU does not read/write to/from that
- buffer. However, this requires extra care from the driver -- it must
- guarantee memory consistency by issuing a cache flush/sync when
- consistency is needed. If this flag is set V4L2 will attempt to
- allocate the buffer in non-coherent memory. The flag takes effect
- only if the buffer is used for :ref:`memory mapping <mmap>` I/O and the
- queue reports the :ref:`V4L2_BUF_CAP_SUPPORTS_MMAP_CACHE_HINTS
- <V4L2-BUF-CAP-SUPPORTS-MMAP-CACHE-HINTS>` capability.
-
.. raw:: latex
\normalsize
@@ -73,6 +73,8 @@ aborting or finishing any DMA in progress, an implicit
.. tabularcolumns:: |p{4.4cm}|p{4.4cm}|p{8.5cm}|
+.. cssclass:: longtable
+
.. flat-table:: struct v4l2_requestbuffers
:header-rows: 0
:stub-columns: 0
@@ -123,14 +125,6 @@ aborting or finishing any DMA in progress, an implicit
.. _V4L2-BUF-CAP-SUPPORTS-MAX-NUM-BUFFERS:
.. _V4L2-BUF-CAP-SUPPORTS-REMOVE-BUFS:
-.. raw:: latex
-
- \footnotesize
-
-.. tabularcolumns:: |p{8.1cm}|p{2.2cm}|p{7.0cm}|
-
-.. cssclass:: longtable
-
.. flat-table:: V4L2 Buffer Capabilities Flags
:header-rows: 0
:stub-columns: 0
@@ -167,6 +161,29 @@ aborting or finishing any DMA in progress, an implicit
:ref:`V4L2_BUF_FLAG_NO_CACHE_CLEAN <V4L2-BUF-FLAG-NO-CACHE-CLEAN>` and
:ref:`V4L2_MEMORY_FLAG_NON_COHERENT <V4L2-MEMORY-FLAG-NON-COHERENT>`.
+.. _memory-flags:
+.. _V4L2-MEMORY-FLAG-NON-COHERENT:
+
+.. flat-table:: Memory Consistency Flags
+ :header-rows: 0
+ :stub-columns: 0
+ :widths: 3 1 4
+
+ * - ``V4L2_MEMORY_FLAG_NON_COHERENT``
+ - 0x00000001
+ - A buffer is allocated either in coherent (it will be automatically
+ coherent between the CPU and the bus) or non-coherent memory. The
+ latter can provide performance gains, for instance the CPU cache
+ sync/flush operations can be avoided if the buffer is accessed by the
+ corresponding device only and the CPU does not read/write to/from that
+ buffer. However, this requires extra care from the driver -- it must
+ guarantee memory consistency by issuing a cache flush/sync when
+ consistency is needed. If this flag is set V4L2 will attempt to
+ allocate the buffer in non-coherent memory. The flag takes effect
+ only if the buffer is used for :ref:`memory mapping <mmap>` I/O and the
+ queue reports the :ref:`V4L2_BUF_CAP_SUPPORTS_MMAP_CACHE_HINTS
+ <V4L2-BUF-CAP-SUPPORTS-MMAP-CACHE-HINTS>` capability.
+
.. raw:: latex
\normalsize