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

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@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.

     - 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