[libre-riscv-dev] Status on Our RISCV Implementation

[Luke Kenneth Casson Leighton]

On Tue, Mar 24, 2020 at 1:11 PM Immanuel, Yehowshua U
<yimmanuel3 at gatech.edu> wrote:

> > nope.  not for RISC-V.  userspace only.
>
> So I guess we’d have a POWER kernel…

correct.  and POWER TLBs and MMU.

> If a binary tries to call RISCV instructions to set supervisor mode register - how is that handled?

from userspace? fail... just like any other userspace RISC-V program
is not permitted to set a supervisor mode register on any standard
RISC-V system.

there will *be* no supervisor mode RISC-V... therefore implementation
of supervisor mode RISC-V registers is completely unnecessary.

userspace RISC-V is only permitted to set userspace RISC-V CSRs.

l.