Re: [PATCH v2 1/3] powerpc/64s: Replace RFI by RFI_TO_KERNEL and remove RFI

[Nicholas Piggin]

Excerpts from Christophe Leroy's message of November 9, 2020 2:57 am:
> In head_64.S, we have two places using RFI to return to
> kernel. Use RFI_TO_KERNEL instead.
> 
> They are the two only places using RFI on book3s/64, so
> the RFI macro can go away.

Looks good to me.

Acked-by: Nicholas Piggin <npiggin@xxxxxxxxx>

> 
> Signed-off-by: Christophe Leroy <christophe.leroy@xxxxxxxxxx>
> ---
>  arch/powerpc/include/asm/ppc_asm.h | 1 -
>  arch/powerpc/kernel/head_64.S      | 9 +++++++--
>  2 files changed, 7 insertions(+), 3 deletions(-)
> 
> diff --git a/arch/powerpc/include/asm/ppc_asm.h b/arch/powerpc/include/asm/ppc_asm.h
> index 511786f0e40d..bedf3eb52ebc 100644
> --- a/arch/powerpc/include/asm/ppc_asm.h
> +++ b/arch/powerpc/include/asm/ppc_asm.h
> @@ -495,7 +495,6 @@ END_FTR_SECTION_NESTED(CPU_FTR_CELL_TB_BUG, CPU_FTR_CELL_TB_BUG, 96)
>  #endif
>  
>  #ifdef CONFIG_PPC_BOOK3S_64
> -#define RFI		rfid
>  #define MTMSRD(r)	mtmsrd	r
>  #define MTMSR_EERI(reg)	mtmsrd	reg,1
>  #else
> diff --git a/arch/powerpc/kernel/head_64.S b/arch/powerpc/kernel/head_64.S
> index 1510b2a56669..ecf9a88988ff 100644
> --- a/arch/powerpc/kernel/head_64.S
> +++ b/arch/powerpc/kernel/head_64.S
> @@ -41,6 +41,11 @@
>  #include <asm/ppc-opcode.h>
>  #include <asm/export.h>
>  #include <asm/feature-fixups.h>
> +#ifdef CONFIG_PPC_BOOK3S
> +#include <asm/exception-64s.h>
> +#else
> +#include <asm/exception-64e.h>
> +#endif
>  
>  /* The physical memory is laid out such that the secondary processor
>   * spin code sits at 0x0000...0x00ff. On server, the vectors follow
> @@ -829,7 +834,7 @@ __secondary_start:
>  
>  	mtspr	SPRN_SRR0,r3
>  	mtspr	SPRN_SRR1,r4
> -	RFI
> +	RFI_TO_KERNEL
>  	b	.	/* prevent speculative execution */
>  
>  /* 
> @@ -966,7 +971,7 @@ start_here_multiplatform:
>  	ld	r4,PACAKMSR(r13)
>  	mtspr	SPRN_SRR0,r3
>  	mtspr	SPRN_SRR1,r4
> -	RFI
> +	RFI_TO_KERNEL
>  	b	.	/* prevent speculative execution */
>  
>  	/* This is where all platforms converge execution */
> -- 
> 2.25.0
> 
>