Re: [PATCH v2 1/5] media: iris: Add dma sync calls for input and output buffers
Dmitry Baryshkov <[email protected]>
| Newsgroups | org.kernel.vger.linux-arm-msm,org.kernel.vger.linux-devicetree,org.kernel.vger.linux-kernel,org.kernel.vger.linux-media |
|---|---|
| Message-ID | <235vlp2bxpqpvgtcqlj3gyh2akclnit4p5lo2boagn4xsgzfeo@qnehnkaye2ru> |
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 <[email protected]> > --- > drivers/media/platform/qcom/iris/iris_buffer.c | 7 +++++++ > 1 file changed, 7 insertions(+) > Missing Fixes tag -- With best wishes Dmitry