dma_alloc_coherent
by zvivered from LinuxQuestions.org on (#5SAEK)
Hello,
Under Centos 8.2(x64) I'm using dma_alloc_coherent to allocate a contiguous RAM used for DMA from FPGA to RAM.
How can I set this area to be not cacheable ?
Is this really a coherentbuffer ?
If yes, then O.S should invalidate the cache automatically so that I always read a fresh data from cache.
In what case I should also use dma_map_single and also dma_alloc_coherent ?
Thank you,
Zvika
Under Centos 8.2(x64) I'm using dma_alloc_coherent to allocate a contiguous RAM used for DMA from FPGA to RAM.
How can I set this area to be not cacheable ?
Is this really a coherentbuffer ?
If yes, then O.S should invalidate the cache automatically so that I always read a fresh data from cache.
In what case I should also use dma_map_single and also dma_alloc_coherent ?
Thank you,
Zvika