Displaying 10 results from an estimated 10 matches for "v4l2_flag_memory_non_consistent".
2020 Aug 19
4
[PATCH 05/28] media/v4l2: remove V4L2-FLAG-MEMORY-NON-CONSISTENT
...a/Documentation/userspace-api/media/v4l/buffer.rst
> +++ b/Documentation/userspace-api/media/v4l/buffer.rst
> @@ -701,23 +701,6 @@ Memory Consistency Flags
> :stub-columns: 0
> :widths: 3 1 4
>
> - * .. _`V4L2-FLAG-MEMORY-NON-CONSISTENT`:
> -
> - - ``V4L2_FLAG_MEMORY_NON_CONSISTENT``
> - - 0x00000001
> - - A buffer is allocated either in consistent (it will be automatically
> - coherent between the CPU and the bus) or non-consistent memory. The
> - latter can provide performance gains, for instance the CPU cache
> - sync/flush operat...
2020 Aug 19
0
[PATCH 05/28] media/v4l2: remove V4L2-FLAG-MEMORY-NON-CONSISTENT
...nimplemented except on PARISC and some MIPS configs, and about to be
>> removed.
>
> It is implemented by the generic DMA mapping layer [1], which is used
> by a number of architectures including ARM64 and supposed to be used
> by new architectures going forward.
AFAICS all that V4L2_FLAG_MEMORY_NON_CONSISTENT does is end up
controling whether DMA_ATTR_NON_CONSISTENT is added to vb2_queue::dma_attrs.
Please can you point to where DMA_ATTR_NON_CONSISTENT does anything at
all on arm64?
Also, I posit that videobuf2 is not actually relying on
DMA_ATTR_NON_CONSISTENT anyway, since it's clearly not us...
2020 Aug 19
0
[PATCH 05/28] media/v4l2: remove V4L2-FLAG-MEMORY-NON-CONSISTENT
...752aaf414a7..2044ed13cd9d7d 100644
--- a/Documentation/userspace-api/media/v4l/buffer.rst
+++ b/Documentation/userspace-api/media/v4l/buffer.rst
@@ -701,23 +701,6 @@ Memory Consistency Flags
:stub-columns: 0
:widths: 3 1 4
- * .. _`V4L2-FLAG-MEMORY-NON-CONSISTENT`:
-
- - ``V4L2_FLAG_MEMORY_NON_CONSISTENT``
- - 0x00000001
- - A buffer is allocated either in consistent (it will be automatically
- coherent between the CPU and the bus) or non-consistent memory. The
- latter can provide performance gains, for instance the CPU cache
- sync/flush operations can be avoided if the buffer is access...
2020 Sep 15
0
[PATCH 01/18] media/v4l2: remove V4L2-FLAG-MEMORY-NON-CONSISTENT flag
...752aaf414a7..2044ed13cd9d7d 100644
--- a/Documentation/userspace-api/media/v4l/buffer.rst
+++ b/Documentation/userspace-api/media/v4l/buffer.rst
@@ -701,23 +701,6 @@ Memory Consistency Flags
:stub-columns: 0
:widths: 3 1 4
- * .. _`V4L2-FLAG-MEMORY-NON-CONSISTENT`:
-
- - ``V4L2_FLAG_MEMORY_NON_CONSISTENT``
- - 0x00000001
- - A buffer is allocated either in consistent (it will be automatically
- coherent between the CPU and the bus) or non-consistent memory. The
- latter can provide performance gains, for instance the CPU cache
- sync/flush operations can be avoided if the buffer is access...
2020 Aug 19
5
[PATCH 05/28] media/v4l2: remove V4L2-FLAG-MEMORY-NON-CONSISTENT
...some MIPS configs, and about to be
> >> removed.
> >
> > It is implemented by the generic DMA mapping layer [1], which is used
> > by a number of architectures including ARM64 and supposed to be used
> > by new architectures going forward.
>
> AFAICS all that V4L2_FLAG_MEMORY_NON_CONSISTENT does is end up
> controling whether DMA_ATTR_NON_CONSISTENT is added to vb2_queue::dma_attrs.
>
> Please can you point to where DMA_ATTR_NON_CONSISTENT does anything at
> all on arm64?
>
With the default config it doesn't, but with
CONFIG_DMA_NONCOHERENT_CACHE_SYNC enabled it ma...
2020 Aug 19
0
[PATCH 05/28] media/v4l2: remove V4L2-FLAG-MEMORY-NON-CONSISTENT
...about to be
>>>> removed.
>>>
>>> It is implemented by the generic DMA mapping layer [1], which is used
>>> by a number of architectures including ARM64 and supposed to be used
>>> by new architectures going forward.
>>
>> AFAICS all that V4L2_FLAG_MEMORY_NON_CONSISTENT does is end up
>> controling whether DMA_ATTR_NON_CONSISTENT is added to vb2_queue::dma_attrs.
>>
>> Please can you point to where DMA_ATTR_NON_CONSISTENT does anything at
>> all on arm64?
>>
>
> With the default config it doesn't, but with
> CONFIG_DMA_N...
2020 Aug 19
39
a saner API for allocating DMA addressable pages
Hi all,
this series replaced the DMA_ATTR_NON_CONSISTENT flag to dma_alloc_attrs
with a separate new dma_alloc_pages API, which is available on all
platforms. In addition to cleaning up the convoluted code path, this
ensures that other drivers that have asked for better support for
non-coherent DMA to pages with incurring bounce buffering over can finally
be properly supported.
I'm still a
2020 Aug 19
1
[PATCH 05/28] media/v4l2: remove V4L2-FLAG-MEMORY-NON-CONSISTENT
...removed.
> >>>
> >>> It is implemented by the generic DMA mapping layer [1], which is used
> >>> by a number of architectures including ARM64 and supposed to be used
> >>> by new architectures going forward.
> >>
> >> AFAICS all that V4L2_FLAG_MEMORY_NON_CONSISTENT does is end up
> >> controling whether DMA_ATTR_NON_CONSISTENT is added to vb2_queue::dma_attrs.
> >>
> >> Please can you point to where DMA_ATTR_NON_CONSISTENT does anything at
> >> all on arm64?
> >>
> >
> > With the default config it doesn...
2020 Sep 14
20
a saner API for allocating DMA addressable pages v2
Hi all,
this series replaced the DMA_ATTR_NON_CONSISTENT flag to dma_alloc_attrs
with a separate new dma_alloc_pages API, which is available on all
platforms. In addition to cleaning up the convoluted code path, this
ensures that other drivers that have asked for better support for
non-coherent DMA to pages with incurring bounce buffering over can finally
be properly supported.
I'm still a
2020 Sep 15
32
a saner API for allocating DMA addressable pages v3
Hi all,
this series replaced the DMA_ATTR_NON_CONSISTENT flag to dma_alloc_attrs
with a separate new dma_alloc_pages API, which is available on all
platforms. In addition to cleaning up the convoluted code path, this
ensures that other drivers that have asked for better support for
non-coherent DMA to pages with incurring bounce buffering over can finally
be properly supported.
As a follow up I