Re: [PATCH 1/7] RISC-V: Detect XVentanaCondOps from ISA string

Andrew Jones
2023-09-20T07:38:24Z

On Tue, Sep 19, 2023 at 09:23:37AM +0530, Anup Patel wrote:
> The Veyron-V1 CPU supports custom conditional arithmetic and
> conditional-select/move operations referred to as XVentanaCondOps
> extension. In fact, QEMU RISC-V also has support for emulating
> XVentanaCondOps extension.
>
> Let us detect XVentanaCondOps extension from ISA string available
> through DT or ACPI.
>
> Signed-off-by: Anup Patel <apatel@ventanamicro.com>
> ---
> Documentation/devicetree/bindings/riscv/extensions.yaml | 7 +++++++
> arch/riscv/include/asm/hwcap.h | 1 +
> arch/riscv/kernel/cpufeature.c | 1 +
> 3 files changed, 9 insertions(+)
>
> diff --git a/Documentation/devicetree/bindings/riscv/extensions.yaml b/Documentation/devicetree/bindings/riscv/extensions.yaml
> index 36ff6749fbba..cad8ef68eca7 100644
> --- a/Documentation/devicetree/bindings/riscv/extensions.yaml
> +++ b/Documentation/devicetree/bindings/riscv/extensions.yaml
> @@ -171,6 +171,13 @@ properties:
> memory types as ratified in the 20191213 version of the privileged
> ISA specification.
>
> + - const: xventanacondops
> + description: |
> + The Ventana specific XVentanaCondOps extension for conditional
> + arithmetic and conditional-select/move operations defined by the
> + Ventana custom extensions specification v1.0.1 (or higher) at
> + https://github.com/ventanamicro/ventana-custom-extensions/releases.
> +
> - const: zba
> description: |
> The standard Zba bit-manipulation extension for address generation
> diff --git a/arch/riscv/include/asm/hwcap.h b/arch/riscv/include/asm/hwcap.h
> index 0f520f7d058a..b7efe9e2fa89 100644
> --- a/arch/riscv/include/asm/hwcap.h
> +++ b/arch/riscv/include/asm/hwcap.h
> @@ -59,6 +59,7 @@
> #define RISCV_ISA_EXT_ZIFENCEI 41
> #define RISCV_ISA_EXT_ZIHPM 42
> #define RISCV_ISA_EXT_SMSTATEEN 43
> +#define RISCV_ISA_EXT_XVENTANACONDOPS 44
>
> #define RISCV_ISA_EXT_MAX 64
>
> diff --git a/arch/riscv/kernel/cpufeature.c b/arch/riscv/kernel/cpufeature.c
> index 3755a8c2a9de..3a31d34fe709 100644
> --- a/arch/riscv/kernel/cpufeature.c
> +++ b/arch/riscv/kernel/cpufeature.c
> @@ -182,6 +182,7 @@ const struct riscv_isa_ext_data riscv_isa_ext[] = {
> __RISCV_ISA_EXT_DATA(svinval, RISCV_ISA_EXT_SVINVAL),
> __RISCV_ISA_EXT_DATA(svnapot, RISCV_ISA_EXT_SVNAPOT),
> __RISCV_ISA_EXT_DATA(svpbmt, RISCV_ISA_EXT_SVPBMT),
> + __RISCV_ISA_EXT_DATA(xventanacondops, RISCV_ISA_EXT_XVENTANACONDOPS),
> };
>
> const size_t riscv_isa_ext_count = ARRAY_SIZE(riscv_isa_ext);
> --
> 2.34.1
>

Besides Conor's comment about splitting the patch,

Reviewed-by: Andrew Jones <ajones@ventanamicro.com>

Thanks,
drew