Re: [PATCH v4 1/7] riscv: asm: alternative-macros: Introduce ALTERNATIVE_3() macro

Conor Dooley
2022-11-24T19:52:56Z

On Thu, Nov 24, 2022 at 05:22:01PM +0000, Prabhakar wrote:
> From: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>
>
> Introduce ALTERNATIVE_3() macro.

Bit perfunctory I think! There's a lovely comment down below that would
make for a better commit message if you were to yoink it.
Content looks about what I'd expect to see though.

> Signed-off-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>
> ---
> RFC v3 -> v4
> * New patch
> ---
> arch/riscv/include/asm/alternative-macros.h | 94 +++++++++++++++++++++
> 1 file changed, 94 insertions(+)
>
> diff --git a/arch/riscv/include/asm/alternative-macros.h b/arch/riscv/include/asm/alternative-macros.h
> index ec2f3f1b836f..1caf4306b3d6 100644
> --- a/arch/riscv/include/asm/alternative-macros.h
> +++ b/arch/riscv/include/asm/alternative-macros.h
> @@ -69,6 +69,34 @@
> new_c_2, vendor_id_2, errata_id_2, \
> IS_ENABLED(CONFIG_k_2)
>
> +.macro __ALTERNATIVE_CFG_3 old_c, new_c_1, vendor_id_1, errata_id_1, enable_1, \
> + new_c_2, vendor_id_2, errata_id_2, enable_2, \
> + new_c_3, vendor_id_3, errata_id_3, enable_3
> +886 :
> + .option push
> + .option norvc
> + .option norelax
> + \old_c
> + .option pop
> +887 :
> + ALT_NEW_CONTENT \vendor_id_1, \errata_id_1, \enable_1, \new_c_1
> + ALT_NEW_CONTENT \vendor_id_2, \errata_id_2, \enable_2, \new_c_2
> + ALT_NEW_CONTENT \vendor_id_3, \errata_id_3, \enable_3, \new_c_3
> +.endm
> +
> +#define _ALTERNATIVE_CFG_3(old_c, new_c_1, vendor_id_1, errata_id_1, \
> + CONFIG_k_1, \
> + new_c_2, vendor_id_2, errata_id_2, \
> + CONFIG_k_2, \
> + new_c_3, vendor_id_3, errata_id_3, \
> + CONFIG_k_3) \
> + __ALTERNATIVE_CFG_3 old_c, new_c_1, vendor_id_1, errata_id_1, \
> + IS_ENABLED(CONFIG_k_1), \
> + new_c_2, vendor_id_2, errata_id_2, \
> + IS_ENABLED(CONFIG_k_2), \
> + new_c_3, vendor_id_3, errata_id_3, \
> + IS_ENABLED(CONFIG_k_3)
> +
> #else /* !__ASSEMBLY__ */
>
> #include <asm/asm.h>
> @@ -135,6 +163,36 @@
> new_c_2, vendor_id_2, errata_id_2, \
> IS_ENABLED(CONFIG_k_2))
>
> +#define __ALTERNATIVE_CFG_3(old_c, new_c_1, vendor_id_1, errata_id_1, \
> + enable_1, \
> + new_c_2, vendor_id_2, errata_id_2, \
> + enable_2, \
> + new_c_3, vendor_id_3, errata_id_3, \
> + enable_3) \
> + "886 :\n" \
> + ".option push\n" \
> + ".option norvc\n" \
> + ".option norelax\n" \
> + old_c "\n" \
> + ".option pop\n" \
> + "887 :\n" \
> + ALT_NEW_CONTENT(vendor_id_1, errata_id_1, enable_1, new_c_1) \
> + ALT_NEW_CONTENT(vendor_id_2, errata_id_2, enable_2, new_c_2) \
> + ALT_NEW_CONTENT(vendor_id_3, errata_id_3, enable_3, new_c_3)
> +
> +#define _ALTERNATIVE_CFG_3(old_c, new_c_1, vendor_id_1, errata_id_1, \
> + CONFIG_k_1, \
> + new_c_2, vendor_id_2, errata_id_2, \
> + CONFIG_k_2, \
> + new_c_3, vendor_id_3, errata_id_3, \
> + CONFIG_k_3) \
> + __ALTERNATIVE_CFG_3(old_c, new_c_1, vendor_id_1, errata_id_1, \
> + IS_ENABLED(CONFIG_k_1), \
> + new_c_2, vendor_id_2, errata_id_2, \
> + IS_ENABLED(CONFIG_k_2), \
> + new_c_3, vendor_id_3, errata_id_3, \
> + IS_ENABLED(CONFIG_k_3))
> +
> #endif /* __ASSEMBLY__ */
>
> #else /* CONFIG_RISCV_ALTERNATIVE */
> @@ -153,6 +211,14 @@
> CONFIG_k_2) \
> __ALTERNATIVE_CFG old_c
>
> +#define _ALTERNATIVE_CFG_3(old_c, new_c_1, vendor_id_1, errata_id_1, \
> + CONFIG_k_1, \
> + new_c_2, vendor_id_2, errata_id_2, \
> + CONFIG_k_2, \
> + new_c_3, vendor_id_3, errata_id_3, \
> + CONFIG_k_3) \
> + __ALTERNATIVE_CFG old_c
> +
> #else /* !__ASSEMBLY__ */
>
> #define __ALTERNATIVE_CFG(old_c) \
> @@ -167,6 +233,14 @@
> CONFIG_k_2) \
> __ALTERNATIVE_CFG(old_c)
>
> +#define _ALTERNATIVE_CFG_3(old_c, new_c_1, vendor_id_1, errata_id_1, \
> + CONFIG_k_1, \
> + new_c_2, vendor_id_2, errata_id_2, \
> + CONFIG_k_2, \
> + new_c_3, vendor_id_3, errata_id_3, \
> + CONFIG_k_3) \
> + __ALTERNATIVE_CFG(old_c)
> +
> #endif /* __ASSEMBLY__ */
> #endif /* CONFIG_RISCV_ALTERNATIVE */
>
> @@ -202,4 +276,24 @@
> new_content_2, vendor_id_2, \
> errata_id_2, CONFIG_k_2)
>
> +/*
> + * A vendor wants to replace an old_content, but another vendor has used
> + * ALTERNATIVE_2() to patch its customized content at the same location. In
> + * this case, this vendor can create a new macro ALTERNATIVE_3() based
> + * on the following sample code and then replace ALTERNATIVE_2() with
> + * ALTERNATIVE_3() to append its customized content.
> + */
> +#define ALTERNATIVE_3(old_content, new_content_1, vendor_id_1, \
> + errata_id_1, CONFIG_k_1, \
> + new_content_2, vendor_id_2, \
> + errata_id_2, CONFIG_k_2, \
> + new_content_3, vendor_id_3, \
> + errata_id_3, CONFIG_k_3) \
> + _ALTERNATIVE_CFG_3(old_content, new_content_1, vendor_id_1, \
> + errata_id_1, CONFIG_k_1, \
> + new_content_2, vendor_id_2, \
> + errata_id_2, CONFIG_k_2, \
> + new_content_3, vendor_id_3, \
> + errata_id_3, CONFIG_k_3)
> +
> #endif
> --
> 2.25.1