Re: [PATCH v5 06/31] arm64/sysreg: Convert SPSR_ELx to automatic register generation

[Marc Zyngier <maz@kernel.org>]

On Fri, 31 Jul 2026 14:08:34 +0100,
Steffen Eiden <seiden@linux.ibm.com> wrote:
> 
> Convert SPSR_EL{1, 2, 12} to automatic register generation as per
> DDIO616 2026-06. No functional change.
>
> Signed-off-by: Steffen Eiden <seiden@linux.ibm.com>
> ---
>  arch/arm64/include/asm/sysreg.h |  3 --
>  arch/arm64/tools/sysreg         | 72 +++++++++++++++++++++++++++++++++
>  2 files changed, 72 insertions(+), 3 deletions(-)
> 
> diff --git a/arch/arm64/include/asm/sysreg.h b/arch/arm64/include/asm/sysreg.h
> index 4bfdac9401bd..1aa601c95188 100644
> --- a/arch/arm64/include/asm/sysreg.h
> +++ b/arch/arm64/include/asm/sysreg.h
> @@ -295,7 +295,6 @@
>  #define SYS_APGAKEYLO_EL1		sys_reg(3, 0, 2, 3, 0)
>  #define SYS_APGAKEYHI_EL1		sys_reg(3, 0, 2, 3, 1)
>  
> -#define SYS_SPSR_EL1			sys_reg(3, 0, 4, 0, 0)
>  #define SYS_ELR_EL1			sys_reg(3, 0, 4, 0, 1)
>  
>  #define SYS_ICC_PMR_EL1			sys_reg(3, 0, 4, 6, 0)
> @@ -518,7 +517,6 @@
>  #define SYS_VTTBR_EL2			sys_reg(3, 4, 2, 1, 0)
>  
>  #define SYS_HAFGRTR_EL2			sys_reg(3, 4, 3, 1, 6)
> -#define SYS_SPSR_EL2			sys_reg(3, 4, 4, 0, 0)
>  #define SYS_ELR_EL2			sys_reg(3, 4, 4, 0, 1)
>  #define SYS_SP_EL1			sys_reg(3, 4, 4, 1, 0)
>  #define SYS_SPSR_irq			sys_reg(3, 4, 4, 3, 0)
> @@ -604,7 +602,6 @@
>  #define SYS_BRBCR_EL12			sys_reg(2, 5, 9, 0, 0)
>  #define SYS_TTBR0_EL12			sys_reg(3, 5, 2, 0, 0)
>  #define SYS_TTBR1_EL12			sys_reg(3, 5, 2, 0, 1)
> -#define SYS_SPSR_EL12			sys_reg(3, 5, 4, 0, 0)
>  #define SYS_ELR_EL12			sys_reg(3, 5, 4, 0, 1)
>  #define SYS_AFSR0_EL12			sys_reg(3, 5, 5, 1, 0)
>  #define SYS_AFSR1_EL12			sys_reg(3, 5, 5, 1, 1)
> diff --git a/arch/arm64/tools/sysreg b/arch/arm64/tools/sysreg
> index 7cb61aca3797..2a4b94e8c62f 100644
> --- a/arch/arm64/tools/sysreg
> +++ b/arch/arm64/tools/sysreg
> @@ -401,6 +401,78 @@ Res0	3:1
>  Field	0	SO
>  EndSysreg
>  
> +Sysreg	SPSR_EL1	3	0	4	0	0
> +Res0	63:37
> +Field	36	UNIJ
> +Res0	35:34
> +Field	33	PPEND
> +Res0	32
> +Field	31	N
> +Field	30	Z
> +Field	29	C
> +Field	28	V
> +Field	27	Q
> +Field	26:25	IT01
> +Field	24	DIT
> +Field	23	SSBS
> +Field	22	PAN
> +Field	21	SS
> +Field	20	IL
> +Field	19:16	GE
> +Field	15:10	IT27

I'm sorry, but this is complete nonsense. It looks like you have
lifted the AArch32 version of the definition, and not the AArch64 view
(which really is what matters here).

> +Field	9	E
> +Field	8	A
> +Field	7	I
> +Field	6	F
> +Field	5	T
> +Field	4	M4
> +Enum	3:0	M

I don't think you should split the M field as such. The AArch32
encoding uses bit 4, and should be described.

> +	0b0000	EL0
> +	0b0100	EL1t
> +	0b0101	EL1h
> +	0b1000	EL1tnv
> +	0b1001	EL1hnv

Please do *not* invent names. These are EL2t/EL2h, and cannot be
anything else.

	M.

-- 
Without deviation from the norm, progress is not possible.