The current PMP setting uses TOR regions, which does not cover the end of the memory (spec: If PMP entry 0’s A field is set to TOR, zero is used for the lower bound, and so it matches any address y < pmpaddr0).
Proposed new NAPOT PMP covers every byte of physical memory in the 56-bit physical address space.
Quote from Andrew: you need to use a NAPOT PMP if you want to grant permissions to the entire address space.
The current PMP setting uses TOR regions, which does not cover the end of the memory (spec: If PMP entry 0’s A field is set to TOR, zero is used for the lower bound, and so it matches any address y < pmpaddr0).
Proposed new NAPOT PMP covers every byte of physical memory in the 56-bit physical address space.
Quote from Andrew: you need to use a NAPOT PMP if you want to grant permissions to the entire address space.
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