Re: [PATCH V2 0/2] Proposing custom CSR handling logic

[Bin Meng]

On Wed, May 12, 2021 at 2:03 PM Alistair Francis <alistair23@gmail.com> wrote:
>
> On Tue, May 11, 2021 at 8:07 PM Ruinland Chuan-Tzu Tsai
> <ruinland@andestech.com> wrote:
> >
> > Hi all,
> >
> > My sincere apology that I missed the patch to include our own CSR table
> > into the patch series and there were plenty of typos.
> > Thus I'm sending out V2 of these tiny patches.
> >
> > I agree with Alistair's comment on not introducing intrusive code which
> > will interfere the generic code structure. Yet since there are
> > possibilities that some custom CSRs/instructions could be once drafted/
> > proposed by vendors at first, and made themselves into the standard
> > as the implementation become widely adopted.
> >
> > So in this patch set, we humbly utilzed a glib hash table for inserting
> > the `struct riscv_custom_csr_operations`, check if the CSR is a non
> > standard one, and then proceed the desired behavior.
> >
> > Once the non-standard CSRs make themselves into the specification,
> > people could easily plug-and-use the code into CSR operation table
> > inside `csr.c`.
> >
> > Ones may have concerns regarding the check code would introduce
> > further overhead. For those considerations, I guess it could be solved
> > by introducing a build option such as '--enable-riscv-vendor-features'
> > to toggle the code.
> >
> > Cordially yours,
> > Ruinland ChuanTzu Tsai
> >
> > Ruinland Chuan-Tzu Tsai (2):
> >   Adding premliminary support for custom CSR handling mechanism
> >   Adding custom Andes CSR table.
>
> Thanks for the patches.
>
> Can you please include:
>  wangjunqiang@iscas.ac.cn
>  qemu-devel@nongnu.org
>  bin.meng@windriver.com
>
> on future patches so everyone is included.

Thanks Alistair!

>
> >
> >  target/riscv/cpu.c           |  28 ++++++++
> >  target/riscv/cpu.h           |  12 +++-
> >  target/riscv/cpu_bits.h      | 115 ++++++++++++++++++++++++++++++++
> >  target/riscv/csr.c           | 107 ++++++++++++++++++++++++++++--
> >  target/riscv/csr_andes.inc.c | 125 +++++++++++++++++++++++++++++++++++
> >  5 files changed, 381 insertions(+), 6 deletions(-)

I didn't see the original patch set in the ML, nor does it show up on
patchwork. I wonder is it posted on the ML?

Regards,
Bin