[PATCH v4 4/5] riscv: Vector checksum library

[Charlie Jenkins]

On Thu, Sep 14, 2023 at 01:46:29PM +0100, Conor Dooley wrote:
> On Mon, Sep 11, 2023 at 03:57:14PM -0700, Charlie Jenkins wrote:
> > This patch is not ready for merge as vector support in the kernel is
> > limited. However, the code has been tested in QEMU so the algorithms
> > do work. This code requires the kernel to be compiled with C vector
> > support, but that is not yet possible. It is written in assembly
> > rather than using the GCC vector instrinsics because they did not
> > provide optimal code.
> > 
> > Signed-off-by: Charlie Jenkins <charlie at rivosinc.com>
> > ---
> >  arch/riscv/lib/csum.c | 92 +++++++++++++++++++++++++++++++++++++++++++++++++++
> >  1 file changed, 92 insertions(+)
> > 
> > diff --git a/arch/riscv/lib/csum.c b/arch/riscv/lib/csum.c
> > index 47d98c51bab2..eb4596fc7f5b 100644
> > --- a/arch/riscv/lib/csum.c
> > +++ b/arch/riscv/lib/csum.c
> > @@ -12,6 +12,10 @@
> >  
> >  #include <net/checksum.h>
> >  
> > +#ifdef CONFIG_RISCV_ISA_V
> > +#include <riscv_vector.h>
> 
> What actually includes this header, I don't see it in either Andy's
> in-kernel vector series or Bjorn's blake2 one.
> Can you link to the pre-requisites in your cover letter please.
> 
> Thanks,
> Conor.

It is defined here:
https://github.com/riscv-non-isa/rvv-intrinsic-doc/blob/main/doc/rvv-intrinsic-spec.adoc.
The header is for the vector intrinsics that are supported by llvm and
gcc.

- Charlie