Re: [PATCH] Add an ISA requirement section
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Thanks for adding this.
For systems that support little-endian, the ISA spec already requires that mstatus.MBE be reset to 0. Furthermore, the ISA spec does not permit hardwiring SBE or UBE to a value that MBE does not support. (And of course the reset values of SBE and UBE are immaterial, since they don't affect M-mode software and M-mode software must initialize the rest of mstatus prior to entering S-mode or U-mode.)
If we combine all of these facts, we can replace the following sentence
Platforms must fully support Little-Endian operation and must come up in this mode of operation after power-on reset
with the more precise constraint
Implementations must not hardwire the mstatus.MBE field to 1.
and we will still obtain the desired result.
On Thu, Jul 22, 2021 at 1:00 AM Atish Patra <atish.patra@...> wrote:
There are few ISA level requirements/strong recommendations that platform