Re: [PATCH v6 07/21] RISC-V: Add Sscfg extension CSR definition
From: Charlie Jenkins
Date: Mon Jun 22 2026 - 02:46:31 EST
On Mon, Jun 08, 2026 at 11:01:21PM -0700, Atish Patra wrote:
> From: Kaiwen Xue <kaiwenx@xxxxxxxxxxxx>
>
> This adds the scountinhibit CSR definition and S-mode accessible hpmevent
> bits defined by smcdeleg/ssccfg. scountinhibit allows S-mode to start/stop
> counters directly from S-mode without invoking SBI calls to M-mode. It is
> also used to figure out the counters delegated to S-mode by the M-mode as
> well.
>
> Signed-off-by: Kaiwen Xue <kaiwenx@xxxxxxxxxxxx>
> Reviewed-by: Clément Léger <cleger@xxxxxxxxxxxx>
> ---
> arch/riscv/include/asm/csr.h | 26 ++++++++++++++++++++++++++
> 1 file changed, 26 insertions(+)
>
> diff --git a/arch/riscv/include/asm/csr.h b/arch/riscv/include/asm/csr.h
> index b4551a6cf7cb..26cb78dee2fd 100644
> --- a/arch/riscv/include/asm/csr.h
> +++ b/arch/riscv/include/asm/csr.h
> @@ -241,6 +241,31 @@
> #define SMSTATEEN0_HSENVCFG (_ULL(1) << SMSTATEEN0_HSENVCFG_SHIFT)
> #define SMSTATEEN0_SSTATEEN0_SHIFT 63
> #define SMSTATEEN0_SSTATEEN0 (_ULL(1) << SMSTATEEN0_SSTATEEN0_SHIFT)
> +/* HPMEVENT bits. These are accessible in S-mode via Smcdeleg/Ssccfg */
> +#ifdef CONFIG_64BIT
> +#define HPMEVENT_OF (BIT_ULL(63))
> +#define HPMEVENT_MINH (BIT_ULL(62))
> +#define HPMEVENT_SINH (BIT_ULL(61))
> +#define HPMEVENT_UINH (BIT_ULL(60))
> +#define HPMEVENT_VSINH (BIT_ULL(59))
> +#define HPMEVENT_VUINH (BIT_ULL(58))
> +#else
> +#define HPMEVENTH_OF (BIT_ULL(31))
> +#define HPMEVENTH_MINH (BIT_ULL(30))
> +#define HPMEVENTH_SINH (BIT_ULL(29))
> +#define HPMEVENTH_UINH (BIT_ULL(28))
> +#define HPMEVENTH_VSINH (BIT_ULL(27))
> +#define HPMEVENTH_VUINH (BIT_ULL(26))
Since these are rv32 bits for a 32-bit register, I think these should be
BIT() instead of BIT_ULL()
> +
> +#define HPMEVENT_OF (HPMEVENTH_OF << 32)
> +#define HPMEVENT_MINH (HPMEVENTH_MINH << 32)
> +#define HPMEVENT_SINH (HPMEVENTH_SINH << 32)
> +#define HPMEVENT_UINH (HPMEVENTH_UINH << 32)
> +#define HPMEVENT_VSINH (HPMEVENTH_VSINH << 32)
> +#define HPMEVENT_VUINH (HPMEVENTH_VUINH << 32)
These definitions are identical to the rv64 ones, can these be removed
and can you move the rv64 definitions to be global?
- Charlie
> +#endif
> +
> +#define SISELECT_SSCCFG_BASE 0x40
>
> /* mseccfg bits */
> #define MSECCFG_PMM ENVCFG_PMM
> @@ -322,6 +347,7 @@
> #define CSR_SCOUNTEREN 0x106
> #define CSR_SENVCFG 0x10a
> #define CSR_SSTATEEN0 0x10c
> +#define CSR_SCOUNTINHIBIT 0x120
> #define CSR_SSCRATCH 0x140
> #define CSR_SEPC 0x141
> #define CSR_SCAUSE 0x142
>
> --
> 2.53.0-Meta
>
>
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