Re: [RISC-V] [tech-virt-mem] Help needed on physical address issues


Allen Baum
 

The ACTs will test that bits above b38 match b38 if SV39 is enabled
Likewise for SV48 and SV 57.
There is no SV64 yet, so any VA bits above b56 that don't match b56 are expected to always trap.

If a PMA doesn't do that, it will fail ACTs 

Greg: are you saying the canonicity boundary of VAs is always bit 56? Because that's not my reading.
For PAs, on the other hand, the PA width is not an architectural constant, its an inplmentation choice.
ACTs expect the DUT config YAML to specify how wide the PA is, and any non-zero bits above that are expected to trap.

@Bill.McSpadden: this is another thing that Sail needs to be aware of (it's in my list of unnamed architectural options).



On Thu, Aug 11, 2022 at 8:30 PM Ke Chai <ck.rickytino@...> wrote:
Thanks again to everyone! These answers make sense to me. 

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