5.5.6. Memory system implications for AXI accesses

The attributes of the memory being accessed can affect an AXI access. The memory system can cache any Normal memory address that is marked as either:

However, Device and Strongly-ordered memory is always Non-cacheable. Also, any unaligned access to Device or Strongly-ordered memory generates alignment UsageFault and therefore does not cause any AXI transfer. This means that the access examples given in this chapter never show unaligned accesses to Device or Strongly-ordered memory.


Memory regions marked as Non-Cacheable Normal must not be used to access read-sensitive peripherals in a system. This is because read transactions to these regions from the processor can be repeated multiple times if the originating load instruction is interrupted.

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