Re: [PATCH v7 08/16] riscv: add ISA parsing for Zca, Zcf, Zcd and Zcb

[Conor Dooley <conor@kernel.org>]

[-- Attachment #1: Type: text/plain, Size: 3252 bytes --]

On Wed, Jun 19, 2024 at 01:35:18PM +0200, Clément Léger wrote:
> The Zc* standard extension for code reduction introduces new extensions.
> This patch adds support for Zca, Zcf, Zcd and Zcb. Zce, Zcmt and Zcmp
> are left out of this patch since they are targeting microcontrollers/
> embedded CPUs instead of application processors.
> 
> Signed-off-by: Clément Léger <cleger@rivosinc.com>
> Reviewed-by: Conor Dooley <conor.dooley@microchip.com>
> ---
>  arch/riscv/include/asm/hwcap.h |  4 +++
>  arch/riscv/kernel/cpufeature.c | 55 +++++++++++++++++++++++++++++++++-
>  2 files changed, 58 insertions(+), 1 deletion(-)
> 
> diff --git a/arch/riscv/include/asm/hwcap.h b/arch/riscv/include/asm/hwcap.h
> index 18859277843a..b12ae3f2141c 100644
> --- a/arch/riscv/include/asm/hwcap.h
> +++ b/arch/riscv/include/asm/hwcap.h
> @@ -87,6 +87,10 @@
>  #define RISCV_ISA_EXT_ZVE64F		78
>  #define RISCV_ISA_EXT_ZVE64D		79
>  #define RISCV_ISA_EXT_ZIMOP		80
> +#define RISCV_ISA_EXT_ZCA		81
> +#define RISCV_ISA_EXT_ZCB		82
> +#define RISCV_ISA_EXT_ZCD		83
> +#define RISCV_ISA_EXT_ZCF		84
>  
>  #define RISCV_ISA_EXT_XLINUXENVCFG	127
>  
> diff --git a/arch/riscv/kernel/cpufeature.c b/arch/riscv/kernel/cpufeature.c
> index a3af976f36c9..aa631fe49b7c 100644
> --- a/arch/riscv/kernel/cpufeature.c
> +++ b/arch/riscv/kernel/cpufeature.c
> @@ -111,6 +111,9 @@ static int riscv_ext_zicboz_validate(const struct riscv_isa_ext_data *data,
>  
>  #define __RISCV_ISA_EXT_DATA(_name, _id) _RISCV_ISA_EXT_DATA(_name, _id, NULL, 0, NULL)
>  
> +#define __RISCV_ISA_EXT_DATA_VALIDATE(_name, _id, _validate) \
> +			_RISCV_ISA_EXT_DATA(_name, _id, NULL, 0, _validate)
> +
>  /* Used to declare pure "lasso" extension (Zk for instance) */
>  #define __RISCV_ISA_EXT_BUNDLE(_name, _bundled_exts) \
>  	_RISCV_ISA_EXT_DATA(_name, RISCV_ISA_EXT_INVALID, _bundled_exts, \
> @@ -122,6 +125,37 @@ static int riscv_ext_zicboz_validate(const struct riscv_isa_ext_data *data,
>  #define __RISCV_ISA_EXT_SUPERSET_VALIDATE(_name, _id, _sub_exts, _validate) \
>  	_RISCV_ISA_EXT_DATA(_name, _id, _sub_exts, ARRAY_SIZE(_sub_exts), _validate)
>  
> +static int riscv_ext_zca_depends(const struct riscv_isa_ext_data *data,

It's super minor, but my OCD doesn't like this being called "depends"
when the others are all called "validate".

> +				 const unsigned long *isa_bitmap)
> +{
> +	if (__riscv_isa_extension_available(isa_bitmap, RISCV_ISA_EXT_ZCA))
> +		return 0;
> +
> +	return -EPROBE_DEFER;
> +}
> +static int riscv_ext_zcd_validate(const struct riscv_isa_ext_data *data,
> +				  const unsigned long *isa_bitmap)
> +{
> +	if (__riscv_isa_extension_available(isa_bitmap, RISCV_ISA_EXT_ZCA) &&
> +	    __riscv_isa_extension_available(isa_bitmap, RISCV_ISA_EXT_d))
> +		return 0;
> +
> +	return -EPROBE_DEFER;
> +}
> +
> +static int riscv_ext_zcf_validate(const struct riscv_isa_ext_data *data,
> +				  const unsigned long *isa_bitmap)
> +{
> +	if (IS_ENABLED(CONFIG_64BIT))
> +		return -EINVAL;
> +
> +	if (__riscv_isa_extension_available(isa_bitmap, RISCV_ISA_EXT_ZCA) &&
> +	    __riscv_isa_extension_available(isa_bitmap, RISCV_ISA_EXT_f))
> +		return 0;
> +
> +	return -EPROBE_DEFER;
> +}

[-- Attachment #2: signature.asc --]
[-- Type: application/pgp-signature, Size: 228 bytes --]