GPU access to memory allocated by dma_alloc_coherent

[AastaLLL]

Hi,

1. There are some topics relates to GPU access for dma_alloc_coherent buffer before.

How to access dma_alloc_coherent memory from CUDA?

Hi, Sorry for keeping you waiting. Could you help to check the memory allocated with dma_alloc_coherent is cacheable or non-cacheable? If the buffer exposed to CUDA is cacheable, the mapping should work fine. Thanks.

The conclusion is that if the buffer is cacheable, it should work with EGL mapping.
However, we haven’t received any feedback from the user about the result.

2.
Pinned memory needs to be a paged-lock host memory.
We don’t have too much experience on the dma_alloc_coherent buffer.
It’s recommended to give it a try directly.

1. CUDA for Tegra — CUDA for Tegra 12.3 documentation

3.
No. The access needs to go through EGL mapping.
You will need to make sure the EGL mapping is working first.

Thanks.