Re: [PATCH 6/8] bfd/binutils: add support for RISC-V CSRs in core files

Andrew Burgess
2020-12-14T13:37:11Z

* Jim Wilson <jimw@sifive.com> [2020-12-02 15:50:58 -0800]:

> On Wed, Dec 2, 2020 at 9:39 AM Andrew Burgess <andrew.burgess@embecosm.com>
> wrote:
>
> > diff --git a/include/elf/common.h b/include/elf/common.h
> > index 1dbf0b11983..54d5d989a39 100644
> > --- a/include/elf/common.h
> > +++ b/include/elf/common.h
> > @@ -663,6 +663,8 @@
> > /* note name must be "LINUX". */
> > #define NT_ARC_V2 0x600 /* ARC HS accumulator/extra
> > registers. */
> > /* note name must be "LINUX". */
> > +#define NT_RISCV_CSR 0x501 /* RISC-V Control and Status
> > Registers */
> > + /* note name must be "CORE". */
> > #define NT_SIGINFO 0x53494749 /* Fields of siginfo_t. */
> > #define NT_FILE 0x46494c45 /* Description of mapped
> > files. */
> >
>
> Odd that the 0x5XX numbering was skipped for ARC, though I don't see any
> reason for it, so it appears OK to use for RISC-V. I would suggest keeping
> them in numerical order to make the file easier to read, so if you want to
> use 0x501 put it before the ARC entry.
>
> Otherwise, this looks OK to me with a trivial change here.

On further reflection I wonder if I should submit a patch to the Linux
kernel to try and reserve this (or some other suitable) number,
otherwise there's a risk that whatever we pick could be used by the
kernel for some other architecture?

Thanks,
Andrew