[PATCH v3 1/2] riscv: provide missing base extension functions

[Sean Anderson]

On 3/17/22 2:36 AM, Heinrich Schuchardt wrote:
> Provide library functions to read:
> 
> * machine vendor ID
> * machine architecture ID
> * machine implementation ID
> 
> Signed-off-by: Heinrich Schuchardt <heinrich.schuchardt at canonical.com>
> ---
>   arch/riscv/include/asm/sbi.h |  3 ++
>   arch/riscv/lib/sbi.c         | 65 ++++++++++++++++++++++++++++++++++++
>   2 files changed, 68 insertions(+)
> 
> diff --git a/arch/riscv/include/asm/sbi.h b/arch/riscv/include/asm/sbi.h
> index 76453121ea..81fcfe0b36 100644
> --- a/arch/riscv/include/asm/sbi.h
> +++ b/arch/riscv/include/asm/sbi.h
> @@ -155,6 +155,9 @@ long sbi_get_spec_version(void);
>   int sbi_get_impl_id(void);
>   int sbi_get_impl_version(long *version);
>   int sbi_probe_extension(int ext);
> +int sbi_get_mvendorid(long *mvendorid);
> +int sbi_get_marchid(long *marchid);
> +int sbi_get_mimpid(long *mimpid);
>   void sbi_srst_reset(unsigned long type, unsigned long reason);
>   
>   #endif
> diff --git a/arch/riscv/lib/sbi.c b/arch/riscv/lib/sbi.c
> index d427d1b29e..8724e3a460 100644
> --- a/arch/riscv/lib/sbi.c
> +++ b/arch/riscv/lib/sbi.c
> @@ -127,6 +127,71 @@ int sbi_probe_extension(int extid)
>   	return -ENOTSUPP;
>   }
>   
> +/**
> + * sbi_get_mvendorid() - get machine vendor ID
> + *
> + * @mimpid:	on return machine vendor ID
> + * Return:	0 on success
> + */
> +int sbi_get_mvendorid(long *mvendorid)
> +{
> +	struct sbiret ret;
> +
> +	ret = sbi_ecall(SBI_EXT_BASE, SBI_EXT_BASE_GET_MVENDORID,
> +			0, 0, 0, 0, 0, 0);
> +	if (ret.error)
> +		return -ENOTSUPP;
> +
> +	if (mvendorid)
> +		*mvendorid = ret.value;
> +
> +	return 0;
> +}
> +
> +/**
> + * sbi_get_marchid() - get machine architecture ID
> + *
> + * @mimpid:	on return machine architecture ID
> + * Return:	0 on success
> + */
> +int sbi_get_marchid(long *marchid)
> +{
> +	struct sbiret ret;
> +
> +	ret = sbi_ecall(SBI_EXT_BASE, SBI_EXT_BASE_GET_MARCHID,
> +			0, 0, 0, 0, 0, 0);
> +
> +	if (ret.error)
> +		return -ENOTSUPP;
> +
> +	if (marchid)
> +		*marchid = ret.value;
> +
> +	return 0;
> +}
> +
> +/**
> + * sbi_get_mimpid() - get machine implementation ID
> + *
> + * @mimpid:	on return machine implementation ID
> + * Return:	0 on success
> + */
> +int sbi_get_mimpid(long *mimpid)
> +{
> +	struct sbiret ret;
> +
> +	ret = sbi_ecall(SBI_EXT_BASE, SBI_EXT_BASE_GET_MIMPID,
> +			0, 0, 0, 0, 0, 0);
> +
> +	if (ret.error)
> +		return -ENOTSUPP;
> +
> +	if (mimpid)
> +		*mimpid = ret.value;
> +
> +	return 0;
> +}
> +
>   /**
>    * sbi_srst_reset() - invoke system reset extension
>    *
> 

Perhaps this could be rewritten like

int sbi_get_mimpid(long *mimpid)
{
	return sbi_base_get_info(mimpid, SBI_EXT_BASE_GET_MIMPID);
}

where sbi_base_get_info is common to all 6 of the generic "get info" functions.

The current implementation is fine as well.

Reviewed-by: Sean Anderson <seanga2 at gmail.com>