Re: [PATCH v3 1/2] arm64: smccc: add cache clean/invalidate IDs and return codes

[Andre Przywara <andre.przywara@arm.com>]

Hi,

On 9/10/26 10:21, Srirangan Madhavan wrote:
> Define SMCCC Arch function IDs for CLEAN_INV_MEMREGION and its ATTRIBUTES
> call, and add RATE_LIMITED/BUSY return codes from DEN0028 for callers that
> need transient error handling.
> 
> Signed-off-by: Srirangan Madhavan <smadhavan@nvidia.com>
> Reviewed-by: Jonathan Cameron <jic23@kernel.org>
> ---
>   include/linux/arm-smccc.h       | 21 +++++++++++++++++++--
>   tools/include/linux/arm-smccc.h | 21 +++++++++++++++++++--
>   2 files changed, 38 insertions(+), 4 deletions(-)
> 
> diff --git a/include/linux/arm-smccc.h b/include/linux/arm-smccc.h
> index 4de81848fe2e..2e205320d88a 100644
> --- a/include/linux/arm-smccc.h
> +++ b/include/linux/arm-smccc.hARM_SMCCC_FAST_CALL
> @@ -116,6 +116,22 @@
>   			   ARM_SMCCC_SMC_32,				\
>   			   ARM_SMCCC_OWNER_CPU, 0x10)
>   
> +/*
> + * DEN0028 v1.7 defines these cache maintenance functions as SMC64
> + * because they carry 64-bit memory range arguments.
> + */
> +#define ARM_SMCCC_ARCH_CLEAN_INV_MEMREGION				\
> +	ARM_SMCCC_CALL_VAL(ARM_SMCCC_FAST_CALL,				\
> +			   ARM_SMCCC_SMC_64,				\
> +			   ARM_SMCCC_OWNER_ARCH,			\
> +			   0x5)
> +
> +#define ARM_SMCCC_ARCH_CLEAN_INV_MEMREGION_ATTRIBUTES			\
> +	ARM_SMCCC_CALL_VAL(ARM_SMCCC_FAST_CALL,				\
> +			   ARM_SMCCC_SMC_64,				\
> +			   ARM_SMCCC_OWNER_ARCH,			\
> +			   0x6)
> +
>   #define ARM_SMCCC_VENDOR_HYP_CALL_UID_FUNC_ID				\
>   	ARM_SMCCC_CALL_VAL(ARM_SMCCC_FAST_CALL,				\
>   			   ARM_SMCCC_SMC_32,				\
> @@ -305,13 +321,14 @@
>   			   0x53)
>   
>   /*
> - * Return codes defined in ARM DEN 0070A
> - * ARM DEN 0070A is now merged/consolidated into ARM DEN 0028 C
> + * Return codes defined by Arm SMCCC (DEN0028 v1.7).
>    */
>   #define SMCCC_RET_SUCCESS			0
>   #define SMCCC_RET_NOT_SUPPORTED			-1
>   #define SMCCC_RET_NOT_REQUIRED			-2
>   #define SMCCC_RET_INVALID_PARAMETER		-3
> +#define SMCCC_RET_RATE_LIMITED			-4
> +#define SMCCC_RET_BUSY				-5
>   
>   #ifndef __ASSEMBLY__
>   
> diff --git a/tools/include/linux/arm-smccc.h b/tools/include/linux/arm-smccc.h
> index 63ce9bebccd3..ae5637b3240f 100644
> --- a/tools/include/linux/arm-smccc.h
> +++ b/tools/include/linux/arm-smccc.h

Why is that? Is there any tool using that? I don't think we 
unconditionally sync the two files?

The numbers in the file above match the spec, so for that part:

Reviewed-by: Andre Przywara <andre.przywara@arm.com>

Cheers,
Andre


> @@ -96,6 +96,22 @@
>   			   ARM_SMCCC_SMC_32,				\
>   			   0, 0x3fff)
>   
> +/*
> + * DEN0028 v1.7 defines these cache maintenance functions as SMC64
> + * because they carry 64-bit memory range arguments.
> + */
> +#define ARM_SMCCC_ARCH_CLEAN_INV_MEMREGION				\
> +	ARM_SMCCC_CALL_VAL(ARM_SMCCC_FAST_CALL,				\
> +			   ARM_SMCCC_SMC_64,				\
> +			   ARM_SMCCC_OWNER_ARCH,			\
> +			   0x5)
> +
> +#define ARM_SMCCC_ARCH_CLEAN_INV_MEMREGION_ATTRIBUTES			\
> +	ARM_SMCCC_CALL_VAL(ARM_SMCCC_FAST_CALL,				\
> +			   ARM_SMCCC_SMC_64,				\
> +			   ARM_SMCCC_OWNER_ARCH,			\
> +			   0x6)
> +
>   #define ARM_SMCCC_VENDOR_HYP_CALL_UID_FUNC_ID				\
>   	ARM_SMCCC_CALL_VAL(ARM_SMCCC_FAST_CALL,				\
>   			   ARM_SMCCC_SMC_32,				\
> @@ -182,12 +198,13 @@
>   			   0x53)
>   
>   /*
> - * Return codes defined in ARM DEN 0070A
> - * ARM DEN 0070A is now merged/consolidated into ARM DEN 0028 C
> + * Return codes defined by Arm SMCCC (DEN0028 v1.7).
>    */
>   #define SMCCC_RET_SUCCESS			0
>   #define SMCCC_RET_NOT_SUPPORTED			-1
>   #define SMCCC_RET_NOT_REQUIRED			-2
>   #define SMCCC_RET_INVALID_PARAMETER		-3
> +#define SMCCC_RET_RATE_LIMITED			-4
> +#define SMCCC_RET_BUSY				-5
>   
>   #endif /*__LINUX_ARM_SMCCC_H*/