I am doing some experiments with a crypto device in the OP-TEE kernel. What is the recommended way to allocate physically contiguous memory for DMA? Will using malloc() in the kernel give me physically contiguous memory? ...based on what I see in documentation/optee_design.md it says that the heap is unpaged, which leads me to think that malloc gives contiguous memory, but wanted to confirm.
Thanks, Stuart
Hi Stuart,
Le 7 sept. 2017 11:17 PM, "Stuart Yoder" stuart.yoder@arm.com a écrit :
I am doing some experiments with a crypto device in the OP-TEE kernel. What is the recommended way to allocate physically contiguous memory for DMA? Will using malloc() in the kernel give me physically contiguous memory? ...based on what I see in documentation/optee_design.md it says that the heap is unpaged, which leads me to think that malloc gives contiguous memory, but wanted to confirm.
Yes, malloc() will return contiguous memory. Not sure if it's good for DMA, though, I'm thinking mapping attributes/cacheability, I'll let more knowledgeable people comment ;)
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Jerome Forissier -
Stuart Yoder