DMA deals with which address (physical/virtual addresses) ?
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Answer / embeddedmatters
DMA deals with Physical addresses.
Only when CPU accesses addresses it refers to MMU(Memory
Management Unit) and MMU converts the Physical address to
Virtual address.
But, DMA controller is a device which directly drives the
data and address bus during data transfer. So, it is purely
Physical address. (It never needs to go through MMU &
Virtual addresses).
That is why when writing the device drivers, the physical
address of the data buffer has to be assigned to the DMA.
| Is This Answer Correct ? | 26 Yes | 3 No |
Answer / gladiator
Slight correction
MMU converts virtual addresses to physical addresses using
help from TLB
| Is This Answer Correct ? | 10 Yes | 1 No |
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