Re: [PATCH 1/3] RISC-V: add Bitmanip/Scalar Crypto parsing from DT

[Heiko Stuebner <heiko@sntech.de>]

Am Samstag, 30. April 2022, 15:50:22 CEST schrieb Hongren (Zenithal) Zheng:
> This commit parses Zb/Zk related string from DT and
> output them in cpuinfo
> 
> One thing worth noting is that if DT provides zk,
> all zbkb, zbkc, zbkx and zkn, zkr, zkt would be enabled.
> 
> Note that zk is a valid extension name and the current
> DT binding spec allows this.
> 
> There currently lacks a mechanism to merge them when
> producing cpuinfo. Namely if you provide a riscv,isa
> "rv64imafdc_zk_zks", the cpuinfo output would be
> "rv64imafdc_zbkb_zbkc_zbkx_zknd_zkne_zknh_zkr_zksed
> _zksh_zkt"
> 
> Tested-by: Jiatai He <jiatai2021@iscas.ac.cn>
> Signed-off-by: Hongren (Zenithal) Zheng <i@zenithal.me>
> ---
>  arch/riscv/include/asm/hwcap.h | 14 ++++++++++++++
>  arch/riscv/kernel/cpu.c        | 14 ++++++++++++++
>  arch/riscv/kernel/cpufeature.c | 33 +++++++++++++++++++++++++++++++++
>  3 files changed, 61 insertions(+)
> 
> diff --git a/arch/riscv/include/asm/hwcap.h b/arch/riscv/include/asm/hwcap.h
> index 0734e42f74f2..199eda39e0b8 100644
> --- a/arch/riscv/include/asm/hwcap.h
> +++ b/arch/riscv/include/asm/hwcap.h
> @@ -52,6 +52,20 @@ extern unsigned long elf_hwcap;
>   */
>  enum riscv_isa_ext_id {
>  	RISCV_ISA_EXT_SSCOFPMF = RISCV_ISA_EXT_BASE,
> +	RISCV_ISA_EXT_ZBA,
> +	RISCV_ISA_EXT_ZBB,
> +	RISCV_ISA_EXT_ZBC,
> +	RISCV_ISA_EXT_ZBS,
> +	RISCV_ISA_EXT_ZBKB,
> +	RISCV_ISA_EXT_ZBKC,
> +	RISCV_ISA_EXT_ZBKX,
> +	RISCV_ISA_EXT_ZKNE,
> +	RISCV_ISA_EXT_ZKND,
> +	RISCV_ISA_EXT_ZKNH,
> +	RISCV_ISA_EXT_ZKSED,
> +	RISCV_ISA_EXT_ZKSH,
> +	RISCV_ISA_EXT_ZKR,
> +	RISCV_ISA_EXT_ZKT,
>  	RISCV_ISA_EXT_ID_MAX = RISCV_ISA_EXT_MAX,
>  };
>  
> diff --git a/arch/riscv/kernel/cpu.c b/arch/riscv/kernel/cpu.c
> index ccb617791e56..7251336969c1 100644
> --- a/arch/riscv/kernel/cpu.c
> +++ b/arch/riscv/kernel/cpu.c
> @@ -87,6 +87,20 @@ int riscv_of_parent_hartid(struct device_node *node)
>   *    extensions by an underscore.
>   */
>  static struct riscv_isa_ext_data isa_ext_arr[] = {
> +	__RISCV_ISA_EXT_DATA(zba, RISCV_ISA_EXT_ZBA),
> +	__RISCV_ISA_EXT_DATA(zbb, RISCV_ISA_EXT_ZBB),
> +	__RISCV_ISA_EXT_DATA(zbc, RISCV_ISA_EXT_ZBC),
> +	__RISCV_ISA_EXT_DATA(zbkb, RISCV_ISA_EXT_ZBKB),
> +	__RISCV_ISA_EXT_DATA(zbkc, RISCV_ISA_EXT_ZBKC),
> +	__RISCV_ISA_EXT_DATA(zbkx, RISCV_ISA_EXT_ZBKX),
> +	__RISCV_ISA_EXT_DATA(zbs, RISCV_ISA_EXT_ZBS),
> +	__RISCV_ISA_EXT_DATA(zknd, RISCV_ISA_EXT_ZKND),
> +	__RISCV_ISA_EXT_DATA(zkne, RISCV_ISA_EXT_ZKNE),
> +	__RISCV_ISA_EXT_DATA(zknh, RISCV_ISA_EXT_ZKNH),
> +	__RISCV_ISA_EXT_DATA(zkr, RISCV_ISA_EXT_ZKR),
> +	__RISCV_ISA_EXT_DATA(zksed, RISCV_ISA_EXT_ZKSED),
> +	__RISCV_ISA_EXT_DATA(zksh, RISCV_ISA_EXT_ZKSH),
> +	__RISCV_ISA_EXT_DATA(zkt, RISCV_ISA_EXT_ZKT),
>  	__RISCV_ISA_EXT_DATA(sscofpmf, RISCV_ISA_EXT_SSCOFPMF),

I guess a bit of sorting rule might be helpful, here it's the additions
above sscofpmf while in the enum it's the other way around.

As the list will get a long longer over time, I guess consistency
might improve readability.

>  	__RISCV_ISA_EXT_DATA("", RISCV_ISA_EXT_MAX),
>  };
> diff --git a/arch/riscv/kernel/cpufeature.c b/arch/riscv/kernel/cpufeature.c
> index 1b2d42d7f589..10f9daf3734e 100644
> --- a/arch/riscv/kernel/cpufeature.c
> +++ b/arch/riscv/kernel/cpufeature.c
> @@ -192,6 +192,39 @@ void __init riscv_fill_hwcap(void)
>  				set_bit(*ext - 'a', this_isa);
>  			} else {
>  				SET_ISA_EXT_MAP("sscofpmf", RISCV_ISA_EXT_SSCOFPMF);
> +				SET_ISA_EXT_MAP("zba"     , RISCV_ISA_EXT_ZBA     );

not sure if the additional whitespaces are really necessary? [especially the ones at the end]
What did checkpatch have to say about them?

> +				SET_ISA_EXT_MAP("zbb"     , RISCV_ISA_EXT_ZBB     );
> +				SET_ISA_EXT_MAP("zbc"     , RISCV_ISA_EXT_ZBC     );
> +				SET_ISA_EXT_MAP("zbs"     , RISCV_ISA_EXT_ZBS     );
> +				SET_ISA_EXT_MAP("zbkb"    , RISCV_ISA_EXT_ZBKB    );
> +				SET_ISA_EXT_MAP("zbkc"    , RISCV_ISA_EXT_ZBKC    );
> +				SET_ISA_EXT_MAP("zbks"    , RISCV_ISA_EXT_ZBKX    );
> +				SET_ISA_EXT_MAP("zknd"    , RISCV_ISA_EXT_ZKND    );
> +				SET_ISA_EXT_MAP("zkne"    , RISCV_ISA_EXT_ZKNE    );
> +				SET_ISA_EXT_MAP("zknh"    , RISCV_ISA_EXT_ZKNH    );
> +				SET_ISA_EXT_MAP("zksed"   , RISCV_ISA_EXT_ZKSED   );
> +				SET_ISA_EXT_MAP("zksh"    , RISCV_ISA_EXT_ZKSH    );
> +				SET_ISA_EXT_MAP("zkr"     , RISCV_ISA_EXT_ZKR     );
> +				SET_ISA_EXT_MAP("zkt"     , RISCV_ISA_EXT_ZKT     );
> +				SET_ISA_EXT_MAP("zkn"     , RISCV_ISA_EXT_ZBKB    );
> +				SET_ISA_EXT_MAP("zkn"     , RISCV_ISA_EXT_ZBKC    );
> +				SET_ISA_EXT_MAP("zkn"     , RISCV_ISA_EXT_ZBKX    );
> +				SET_ISA_EXT_MAP("zkn"     , RISCV_ISA_EXT_ZKND    );
> +				SET_ISA_EXT_MAP("zkn"     , RISCV_ISA_EXT_ZKNE    );
> +				SET_ISA_EXT_MAP("zkn"     , RISCV_ISA_EXT_ZKNH    );
> +				SET_ISA_EXT_MAP("zks"     , RISCV_ISA_EXT_ZBKB    );
> +				SET_ISA_EXT_MAP("zks"     , RISCV_ISA_EXT_ZBKC    );
> +				SET_ISA_EXT_MAP("zks"     , RISCV_ISA_EXT_ZBKX    );
> +				SET_ISA_EXT_MAP("zks"     , RISCV_ISA_EXT_ZKSED   );
> +				SET_ISA_EXT_MAP("zks"     , RISCV_ISA_EXT_ZKSH    );
> +				SET_ISA_EXT_MAP("zk"      , RISCV_ISA_EXT_ZBKB    );
> +				SET_ISA_EXT_MAP("zk"      , RISCV_ISA_EXT_ZBKC    );
> +				SET_ISA_EXT_MAP("zk"      , RISCV_ISA_EXT_ZBKX    );
> +				SET_ISA_EXT_MAP("zk"      , RISCV_ISA_EXT_ZKND    );
> +				SET_ISA_EXT_MAP("zk"      , RISCV_ISA_EXT_ZKNE    );
> +				SET_ISA_EXT_MAP("zk"      , RISCV_ISA_EXT_ZKNH    );
> +				SET_ISA_EXT_MAP("zk"      , RISCV_ISA_EXT_ZKR     );
> +				SET_ISA_EXT_MAP("zk"      , RISCV_ISA_EXT_ZKT     );
>  			}
>  #undef SET_ISA_EXT_MAP
>  		}
>