[PATCH v6 07/21] RISC-V: Add Sscfg extension CSR definition
Atish Patra
atish.patra at linux.dev
Wed Jun 24 00:36:17 PDT 2026
On 6/21/26 11:43 PM, Charlie Jenkins wrote:
> On Mon, Jun 08, 2026 at 11:01:21PM -0700, Atish Patra wrote:
>> From: Kaiwen Xue <kaiwenx at rivosinc.com>
>>
>> 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 at rivosinc.com>
>> Reviewed-by: Clément Léger <cleger at rivosinc.com>
>> ---
>> 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?
Good catch. Will fix this and the above in v8.
> - 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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