Messages in this thread | | | From | Kedareswararao Appana <> | Date | Thu, 23 Aug 2018 20:20:36 +0530 | Subject | Query on dma_set_mask_and_coherent() Usage |
| |
Hi All,
On arm64 platform I have booted Linux only with > 32-bit Address i.e from 0x800000000 (reg = <0x8 0x00000000 0x0 0x80000000>)
In my driver, I am using dma_set_mask_and_coherent(&pdev->dev, DMA_BIT_MASK(32)); which should fail if I boot Linux with the above configuration but the API is returning success.
I have debugged it further and observed that, in the arm64 dma-mapping.c swiotlb is zero resulting dma_supported ops always returning 1
https://elixir.bootlin.com/linux/v4.17.8/source/arch/arm64/mm/dma-mapping.c#L321
I will be grateful if someone can send me some pointers for fixing this issue
Regards, Kedar.
| |