[PATCH v2 3/3] riscv: Add a Zalrsc-only alternative for synchronization in start.S

[Leo Liang]

On Tue, Sep 02, 2025 at 08:19:32AM +0000, Yao Zi wrote:
> Add an alternative implementation that use Zalrsc extension only for
> HART lottery and SMP locking to support SMP on cores without "Zaamo"
> extension available. The Zaamo implementation is still prioritized if
> both of them are available, since it takes fewer instructions.
> 
> Signed-off-by: Yao Zi <ziyao at disroot.org>
> ---
>  arch/riscv/cpu/start.S | 26 +++++++++++++++++++++++++-
>  1 file changed, 25 insertions(+), 1 deletion(-)

Reviewed-by: Leo Yu-Chi Liang <ycliang at andestech.com>