[PATCH v2] RISC-V: Schedule SBI-0.1 for removal

[Andrew Jones]

On Tue, Sep 17, 2024 at 06:53:08AM GMT, Palmer Dabbelt wrote:
> We've said we're going to deprecate SBI-0.1 for a while now, but I
> didn't find that written down anywhere.  So mark SBI-0.1 as deprecated
> and print a timeline for that deprecation on systems that probe it.
> 
> Signed-off-by: Palmer Dabbelt <palmer at rivosinc.com>
> ---
>  arch/riscv/Kconfig      | 17 +++++++++++++----
>  arch/riscv/kernel/sbi.c |  1 +
>  2 files changed, 14 insertions(+), 4 deletions(-)
> 
> diff --git a/arch/riscv/Kconfig b/arch/riscv/Kconfig
> index f00d474e13d0..fad197d5e122 100644
> --- a/arch/riscv/Kconfig
> +++ b/arch/riscv/Kconfig
> @@ -838,12 +838,21 @@ menu "Kernel features"
>  
>  source "kernel/Kconfig.hz"
>  
> -config RISCV_SBI_V01
> -	bool "SBI v0.1 support"
> +config RISCV_SBI_V01_DEPRECATED
> +	bool "SBI v0.1 support (DEPRECATED)"
>  	depends on RISCV_SBI
>  	help
> -	  This config allows kernel to use SBI v0.1 APIs. This will be
> -	  deprecated in future once legacy M-mode software are no longer in use.
> +	  This config allows kernel to use SBI v0.1 APIs.
> +
> +	  SBI v0.1 support has been deprecated and will be removed after the
> +	  2025 LTS.
> +
> +	  If unsure what to do here, say N.
> +
> +config RISCV_SBI_V01
> +	bool
> +	default y
> +	depends on RISCV_SBI_V01_DEPRECATED

I think this could be simplified to

  def_bool RISCV_SBI_V01_DEPRECATED

>  
>  config RISCV_BOOT_SPINWAIT
>  	bool "Spinwait booting method"
> diff --git a/arch/riscv/kernel/sbi.c b/arch/riscv/kernel/sbi.c
> index 837bdab2601b..1209a4e53ed1 100644
> --- a/arch/riscv/kernel/sbi.c
> +++ b/arch/riscv/kernel/sbi.c
> @@ -686,6 +686,7 @@ void __init sbi_init(void)
>  			sbi_debug_console_available = true;
>  		}
>  	} else {
> +		pr_warn("SBI-0.1 is deprecated and scheduled for removal after the 2025 LTS");

I don't think pr_warn appends a newline.

>  		__sbi_set_timer = __sbi_set_timer_v01;
>  		__sbi_send_ipi	= __sbi_send_ipi_v01;
>  		__sbi_rfence	= __sbi_rfence_v01;
> -- 
> 2.45.2
>

Otherwise,

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

Thanks,
drew