[PATCH v4 05/13] riscv: Implement cmpxchg8/16() using Zabha

[Andrew Jones]

On Wed, Jul 31, 2024 at 09:23:57AM GMT, Alexandre Ghiti wrote:
> This adds runtime support for Zabha in cmpxchg8/16() operations.
> 
> Note that in the absence of Zacas support in the toolchain, CAS
> instructions from Zabha won't be used.
> 
> Signed-off-by: Alexandre Ghiti <alexghiti at rivosinc.com>
> ---
>  arch/riscv/Kconfig               | 18 ++++++++
>  arch/riscv/Makefile              |  3 ++
>  arch/riscv/include/asm/cmpxchg.h | 78 ++++++++++++++++++++------------
>  arch/riscv/include/asm/hwcap.h   |  1 +
>  arch/riscv/kernel/cpufeature.c   |  1 +
>  5 files changed, 72 insertions(+), 29 deletions(-)
>

Reviewed-by: Andrew Jones <ajones at ventanamicro.com>