[PATCH v2 00/13] media: rockchip: rga: add support for multi-planar formats

Hans Verkuil hverkuil at xs4all.nl
Sat Nov 25 00:22:42 PST 2023


On 24/11/2023 16:31, Michael Tretter wrote:
> Hi Hans,
> 
> On Fri, 24 Nov 2023 14:39:37 +0100, Hans Verkuil wrote:
>> On 13/10/2023 13:00, Michael Tretter wrote:
>>> This is v2 of the series that adds support for the V4L2 multi-planar API
>>> to the Rockchip RGA driver. Once the RGA driver supports the
>>> multi-planar API, it is easier to share buffers with other V4L2 drivers
>>> that also support the multi-planar API and may not expose planar formats
>>> with contiguous planes.
>>>
>>> v2 fixes the smatch warnings and compile errors of v1. Furthermore, now
>>> the DMA mask is set to 32 bits for coherent, too, and the gfp_flags are
>>> configured to ensure that buffers are allocated in the lower 4GB area.
>>>
>>> With non-contiguous planes, the U and V planes may not start at the same
>>> offset as with the continuous planes. Therefore, the RGA driver cannot
>>> rely on its calculation of the plane offsets based on the format and
>>> frame size anymore, but must remember the offsets when it created the
>>> mapping. Therefore, I also reworked how the DMA mapping is handled.
>>>
>>> As a bonus, the RGA driver should now work correctly on devices with
>>> more than 4 GB of memory. Video buffers should now be allocated within
>>> the 4 GB boundary and an import of buffers that have higher addresses
>>> into the driver should fail.
>>>
>>> Patch 1 fixes the swizzling of RGA formats. While testing all formats of
>>> the driver on rk3568, I discovered that the color channels of the RGB
>>> formats are wrong when converting to NV12. I didn't test this on other
>>> SoCs with an RGA and I am not sure, if they behave differently regarding
>>> the color channels. Please report, if this breaks the color conversion
>>> on other SoCs, and I will make this SoC-specific.
>>>
>>> Patches 2 to 6 are the rework the DMA descriptor handling for the RGA
>>> MMU. The patches clean up, how the driver uses the DMA API, and make the
>>> creation of the descriptor list more explicit. Furthermore, the driver
>>> is changed to keep the mapping per video buffer instead of using a
>>> single mapping that is updated with every buffer.
>>>
>>> Patches 7 to 11 prepare the driver for the multi-planar API including a
>>> cleanup of the format handling in the buffer, and finally switch to the
>>> multi-planar API.
>>
>> Switching over to the multi-planar API is always a bit scary. How did you
>> test this? Using gstreamer? Other apps?
> 
> I tested with GStreamer. My use case is using the RGA to convert RGB Buffers
> to NV12 to feed them to a Hantro JPEG encoder. I also tried to separate the
> preparatory work, the switch to the multi-planar API, and the addition of
> actually multi-planar formats into separate patches.
> 
> Is there anything that I should take special care of or explicitly test, when
> switching the driver to the multi-planar API?

No, I just wanted to have a better overview of how this driver is used and
how you tested it.

Regards,

	Hans

> 
> Michael
> 
>>
>> Regards,
>>
>> 	Hans
>>
>>>
>>> Patch 12 updates the code that creates the DMA-descriptor mapping to
>>> correctly handle buffers with multiple planes. The driver has to iterate
>>> all planes and make them the continuous for the RGA.
>>>
>>> Patch 13 enables the NV12M format, which is the multi-planar variant of
>>> the NV12 format.
>>>
>>> Michael
>>>
>>> Signed-off-by: Michael Tretter <m.tretter at pengutronix.de>
>>> ---
>>> Changes in v2:
>>> - Fix smatch warnings
>>> - Fix cast to dst_mmu_pages/src_mmu_pages to fix compile error in Patch 2
>>> - Remove check for upper_32_bits when filling the DMA descriptor table
>>> - Remove useless dma_sync_single_for_device()
>>> - Set DMA mask for DMA coherent
>>> - Set gfp_flags to __GFP_DMA32
>>> - Link to v1: https://lore.kernel.org/r/20230914-rockchip-rga-multiplanar-v1-0-abfd77260ae3@pengutronix.de
>>>
>>> ---
>>> Michael Tretter (13):
>>>       media: rockchip: rga: fix swizzling for RGB formats
>>>       media: rockchip: rga: extract helper to fill descriptors
>>>       media: rockchip: rga: allocate DMA descriptors per buffer
>>>       media: rockchip: rga: split src and dst buffer setup
>>>       media: rockchip: rga: pre-calculate plane offsets
>>>       media: rockchip: rga: set dma mask to 32 bits
>>>       media: rockchip: rga: use clamp() to clamp size to limits
>>>       media: rockchip: rga: use pixelformat to find format
>>>       media: rockchip: rga: add local variable for pix_format
>>>       media: rockchip: rga: use macros for testing buffer type
>>>       media: rockchip: rga: switch to multi-planar API
>>>       media: rockchip: rga: rework buffer handling for multi-planar formats
>>>       media: rockchip: rga: add NV12M support
>>>
>>>  drivers/media/platform/rockchip/rga/rga-buf.c | 162 ++++++++++++++++------
>>>  drivers/media/platform/rockchip/rga/rga-hw.c  | 146 ++++++++++++--------
>>>  drivers/media/platform/rockchip/rga/rga.c     | 189 ++++++++++++--------------
>>>  drivers/media/platform/rockchip/rga/rga.h     |  35 ++++-
>>>  4 files changed, 328 insertions(+), 204 deletions(-)
>>> ---
>>> base-commit: 2c1bae27df787c9535e48cc27bbd11c3c3e0a235
>>> change-id: 20230914-rockchip-rga-multiplanar-0d7c79b1ba93
>>>
>>> Best regards,
>>
>>




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