Re: [PATCH v2 1/5] media: iris: Add dma sync calls for input and output buffers

From: Vishnu Reddy

Date: Mon Aug 24 2026 - 01:12:48 EST



On 8/19/2026 4:11 AM, Dmitry Baryshkov wrote:
> On Tue, Aug 18, 2026 at 09:24:14PM +0530, Vishnu Reddy wrote:
>> While testing with some higher resolution clips, the venus hardware
>> triggers a fault due to wrong input data being received. Corruption
>> was also observed in the captured output when the client dumped it
>> to a file.
>>
>> On debugging, found that DMA buffers shared between the CPU and the
>> venus video hardware/controller are not in sync. CPU writes to an input
>> buffer can remain in CPU cache without being visible to the video
>> hardware when it reads the same buffer, so the hardware receives input
>> data that does not match what the CPU wrote. Likewise, on the capture
>> path, data written by the video hardware to the output buffer may not
>> be visible to the CPU, so the client reads stale or partial data,
>> resulting in corruption.
>>
>> Add dma sync API calls to synchronize the data between the CPU cache
>> and the venus hardware/controller.
>>
>> Signed-off-by: Vishnu Reddy <busanna.reddy@xxxxxxxxxxxxxxxx>
>> ---
>> drivers/media/platform/qcom/iris/iris_buffer.c | 7 +++++++
>> 1 file changed, 7 insertions(+)
>>
> Missing Fixes tag

Ack. Will add in next revision.

>