[PATCH v1 1/2] RISC-V: move zicsr/zifencei spec version check to Kconfig

[Palmer Dabbelt]

On Fri, 24 Feb 2023 09:00:09 PST (-0800), Conor Dooley wrote:
> On Fri, Feb 24, 2023 at 09:37:28AM -0700, Nathan Chancellor wrote:
>> On Thu, Feb 23, 2023 at 10:05:45PM +0000, Conor Dooley wrote:
>
>> > ---
>> >  arch/riscv/Kconfig  | 10 ++++++++++
>> >  arch/riscv/Makefile |  5 +----
>> >  2 files changed, 11 insertions(+), 4 deletions(-)
>> > 
>> > diff --git a/arch/riscv/Kconfig b/arch/riscv/Kconfig
>> > index cebf0c5f8824..4eb0ef8314b3 100644
>> > --- a/arch/riscv/Kconfig
>> > +++ b/arch/riscv/Kconfig
>> > @@ -288,6 +288,16 @@ config ARCH_RV64I
>> >  
>> >  endchoice
>> >  
>> > +config TOOLCHAIN_NEEDS_SPEC_20191213
>> 
>> This symbol's name is a little confusing to me, how does the toolchain
>> need spec version 20191213. Maybe 'SPEC_20191213' should be something
>> like 'EXPLICIT_ZICSR_ZIFENCEI'? Otherwise, maybe it should be something
>> like 'TOOLCHAIN_HAS_DEFAULT_SPEC_20191213'? Sorry for the bikeshed but I
>> think most Kconfig symbols should be self describing.
>
> Yah I can do that. I actually had this as the DEFAULT_SPEC variant
> before and changed it - I'll switch it to the EXPLICIT one.
> Thanks for taking a look Nathan :)

Another option here would be to use the `-misa-spec` argument for GCC, 
to make it match LLVM's spec version.