On Fri, Jun 21, 2024 at 5:03 PM Yunhui Cui <cuiyunhui@xxxxxxxxxxxxx> wrote:
>
> From: Palmer Dabbelt <palmer@xxxxxxxxxxxx>
>
> A handful of user-visible behavior is based on the frequency of the
> time CSR.
>
> Signed-off-by: Palmer Dabbelt <palmer@xxxxxxxxxxxx>
> Signed-off-by: Yunhui Cui <cuiyunhui@xxxxxxxxxxxxx>
LGTM.
Reviewed-by: Anup Patel <anup@xxxxxxxxxxxxxx>
Regards,
Anup
> ---
> Documentation/arch/riscv/hwprobe.rst | 2 ++
> arch/riscv/include/asm/hwprobe.h | 2 +-
> arch/riscv/include/uapi/asm/hwprobe.h | 1 +
> arch/riscv/kernel/sys_hwprobe.c | 5 +++++
> 4 files changed, 9 insertions(+), 1 deletion(-)
>
> diff --git a/Documentation/arch/riscv/hwprobe.rst b/Documentation/arch/riscv/hwprobe.rst
> index fc015b452ebf..c07f159d8906 100644
> --- a/Documentation/arch/riscv/hwprobe.rst
> +++ b/Documentation/arch/riscv/hwprobe.rst
> @@ -229,3 +229,5 @@ The following keys are defined:
>
> * :c:macro:`RISCV_HWPROBE_KEY_ZICBOZ_BLOCK_SIZE`: An unsigned int which
> represents the size of the Zicboz block in bytes.
> +
> +* :c:macro:`RISCV_HWPROBE_KEY_TIME_CSR_FREQ`: Frequency (in Hz) of `mtime`.
> diff --git a/arch/riscv/include/asm/hwprobe.h b/arch/riscv/include/asm/hwprobe.h
> index 630507dff5ea..150a9877b0af 100644
> --- a/arch/riscv/include/asm/hwprobe.h
> +++ b/arch/riscv/include/asm/hwprobe.h
> @@ -8,7 +8,7 @@
>
> #include <uapi/asm/hwprobe.h>
>
> -#define RISCV_HWPROBE_MAX_KEY 6
> +#define RISCV_HWPROBE_MAX_KEY 7
>
> static inline bool riscv_hwprobe_key_is_valid(__s64 key)
> {
> diff --git a/arch/riscv/include/uapi/asm/hwprobe.h b/arch/riscv/include/uapi/asm/hwprobe.h
> index 7b95fadbea2a..18754341ff14 100644
> --- a/arch/riscv/include/uapi/asm/hwprobe.h
> +++ b/arch/riscv/include/uapi/asm/hwprobe.h
> @@ -73,6 +73,7 @@ struct riscv_hwprobe {
> #define RISCV_HWPROBE_MISALIGNED_UNSUPPORTED (4 << 0)
> #define RISCV_HWPROBE_MISALIGNED_MASK (7 << 0)
> #define RISCV_HWPROBE_KEY_ZICBOZ_BLOCK_SIZE 6
> +#define RISCV_HWPROBE_KEY_TIME_CSR_FREQ 7
> /* Increase RISCV_HWPROBE_MAX_KEY when adding items. */
>
> /* Flags */
> diff --git a/arch/riscv/kernel/sys_hwprobe.c b/arch/riscv/kernel/sys_hwprobe.c
> index 83fcc939df67..fc3b40fb9def 100644
> --- a/arch/riscv/kernel/sys_hwprobe.c
> +++ b/arch/riscv/kernel/sys_hwprobe.c
> @@ -8,6 +8,7 @@
> #include <asm/cacheflush.h>
> #include <asm/cpufeature.h>
> #include <asm/hwprobe.h>
> +#include <asm/delay.h>
> #include <asm/sbi.h>
> #include <asm/switch_to.h>
> #include <asm/uaccess.h>
> @@ -226,6 +227,10 @@ static void hwprobe_one_pair(struct riscv_hwprobe *pair,
> pair->value = riscv_cboz_block_size;
> break;
>
> + case RISCV_HWPROBE_KEY_TIME_CSR_FREQ:
> + pair->value = riscv_timebase;
> + break;
> +
> /*
> * For forward compatibility, unknown keys don't fail the whole
> * call, but get their element key set to -1 and value set to 0
> --
> 2.20.1
>
>
