Re: [PATCH] RISC-V: cpuidle: fix Kconfig select for RISCV_SBI_CPUIDLE

[Palmer Dabbelt]

On Sat, 09 Apr 2022 15:53:17 PDT (-0700), rdunlap@xxxxxxxxxxxxx wrote:
> There can be lots of build errors when building cpuidle-riscv-sbi.o.
> They are all caused by a kconfig problem with this warning:
>
> WARNING: unmet direct dependencies detected for RISCV_SBI_CPUIDLE
>   Depends on [n]: CPU_IDLE [=y] && RISCV [=y] && RISCV_SBI [=n]
>   Selected by [y]:
>   - SOC_VIRT [=y] && CPU_IDLE [=y]
>
> so make the 'select' of RISCV_SBI_CPUIDLE also depend on RISCV_SBI.
>
> Fixes: c5179ef1ca0c ("RISC-V: Enable RISC-V SBI CPU Idle driver for QEMU virt machine")
> Signed-off-by: Randy Dunlap <rdunlap@xxxxxxxxxxxxx>
> Reported-by: kernel test robot <lkp@xxxxxxxxx>
> Cc: Anup Patel <anup.patel@xxxxxxx>
> Cc: Anup Patel <apatel@xxxxxxxxxxxxxxxx>
> Cc: Anup Patel <anup@xxxxxxxxxxxxxx>
> Cc: Palmer Dabbelt <palmer@xxxxxxxxxxxx>
> Cc: linux-pm@xxxxxxxxxxxxxxx
> Cc: linux-riscv@xxxxxxxxxxxxxxxxxxx
> Cc: Paul Walmsley <paul.walmsley@xxxxxxxxxx>
> Cc: Palmer Dabbelt <palmer@xxxxxxxxxxx>
> Cc: Albert Ou <aou@xxxxxxxxxxxxxxxxx>
> ---
>  arch/riscv/Kconfig.socs |    2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
>
> --- a/arch/riscv/Kconfig.socs
> +++ b/arch/riscv/Kconfig.socs
> @@ -38,7 +38,7 @@ config SOC_VIRT
>  	select SIFIVE_PLIC
>  	select PM_GENERIC_DOMAINS if PM
>  	select PM_GENERIC_DOMAINS_OF if PM && OF
> -	select RISCV_SBI_CPUIDLE if CPU_IDLE
> +	select RISCV_SBI_CPUIDLE if CPU_IDLE && RISCV_SBI
>  	help
>  	  This enables support for QEMU Virt Machine.

Sorry to be slow here, I seem to remember having written this before but 
I must have just gotted pulled into something else.

IMO the real bug here is that Kconfig.socs is poorly designed: I 
misunderstood how select works at the time, we should really clean all 
this up (or maybe just remove it entirely?) so we don't have to 
duplicate all these dependencies.

That's a bigger project, though so this is on fixes -- it's way better 
to have the build work.

Thanks!