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Subjectequivalent of phys_to_virt in an iommu system
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Hi,

Assuming at core mmu there is a mapping, V1 -> P1
And at the IOMMU for the device to access a region of DDR there is a
mapping P2 -> P1. [P2 is the address on which device issues a r/w]

Now the device driver does the following.

Line 0: V1 = kmalloc();
Line 1: P2 = dma_map_single(V1)

Now if later in the driver, there is a requirement to get V1 from P2
what is the primitive in linux ?
Also is my understanding of Line 1(above) correct ?


--
-mj


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