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

Anup Patel apatel at ventanamicro.com
Mon Sep 25 06:30:37 PDT 2023


On Tue, Sep 19, 2023 at 12:56 PM Conor Dooley <conor at kernel.org> wrote:
>
> Hey Anup,
>
> 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 at 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.
> > +
>
> For this and the next patch, the binding change needs to be split out
> from the code. checkpatch should've complained about it.

Okay, I will split this patch.

>
> >          - 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),
>
> I've been banging on for a bit about people doing weird stuff to detect
> their vendor extensions, so nice to see it being done properly :)
>
>
> Cheers,
> Conor.
>
> >  };
> >
> >  const size_t riscv_isa_ext_count = ARRAY_SIZE(riscv_isa_ext);
> > --
> > 2.34.1
> >

Regards,
Anup



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