Re: [PATCH v3 3/5] RISC-V: Fix unsupported isa string info.

[Palmer Dabbelt]

On Tue, 06 Aug 2019 18:26:08 PDT (-0700), Paul Walmsley wrote:
> On Wed, 7 Aug 2019, Atish Patra wrote:
>
> > On Tue, 2019-08-06 at 16:27 -0700, Paul Walmsley wrote:
> >
> > > Seems like the "su" should be dropped from mandatory_ext.  What do you
> > > think?
> > >
> >
> > Yup. As DT binding only mention imafdc, mandatory extensions should
> > contain only that and just consider "su" extensions are considered as
> > implicit as we are running Linux.
>
> Discussing this with Andrew and Palmer, it looks like "su" is currently
> non-compliant.  Section 22.6 of the user-level specification states that
> the "s" character indicates that a longer standard supervisor extension
> name will follow.  So far I don't think any of these have been defined.
>
> > Do you think QEMU DT should be updated to reflect that ?
>
> Yes.

https://lists.nongnu.org/archive/html/qemu-riscv/2019-08/msg00141.html

> > > There's no Kconfig option by this name, and we're requiring
> > > compressed
> >
> > Sorry. This was a typo. It should have been CONFIG_RISCV_ISA_C.
> >
> > > instruction support as part of the RISC-V Linux baseline.  Could you
> > > share the rationale behind this?
> >
> > I think I added this check at the config file. Looking at the Kconfig,
> > RISCV_ISA_C is always enabled. So we can drop this.
>
> OK great.  Do you want to resend an updated patch, or would you like me to
> fix it up here?
>
> I'll also send a patch to drop CONFIG_RISCV_ISA_C.
>
>
> - Paul