Re: [kvm-unit-tests PATCH v1 1/4] s390x: lib: Add SCLP toplogy nested level

[Claudio Imbrenda <imbrenda@linux.ibm.com>]

On Mon,  9 Aug 2021 10:48:51 +0200
Pierre Morel <pmorel@linux.ibm.com> wrote:

> The maximum CPU Topology nested level is available with the SCLP
> READ_INFO command inside the byte at offset 15 of the ReadInfo
> structure.
> 
> Let's return this information to check the number of topology nested
> information available with the STSI 15.1.x instruction.
> 
> Signed-off-by: Pierre Morel <pmorel@linux.ibm.com>

Reviewed-by: Claudio Imbrenda <imbrenda@linux.ibm.com>

> ---
>  lib/s390x/sclp.c | 6 ++++++
>  lib/s390x/sclp.h | 4 +++-
>  2 files changed, 9 insertions(+), 1 deletion(-)
> 
> diff --git a/lib/s390x/sclp.c b/lib/s390x/sclp.c
> index 9502d161..ee379ddf 100644
> --- a/lib/s390x/sclp.c
> +++ b/lib/s390x/sclp.c
> @@ -123,6 +123,12 @@ int sclp_get_cpu_num(void)
>  	return read_info->entries_cpu;
>  }
>  
> +int sclp_get_stsi_parm(void)
> +{
> +	assert(read_info);
> +	return read_info->stsi_parm;
> +}
> +
>  CPUEntry *sclp_get_cpu_entries(void)
>  {
>  	assert(read_info);
> diff --git a/lib/s390x/sclp.h b/lib/s390x/sclp.h
> index 28e526e2..1a365958 100644
> --- a/lib/s390x/sclp.h
> +++ b/lib/s390x/sclp.h
> @@ -146,7 +146,8 @@ typedef struct ReadInfo {
>  	SCCBHeader h;
>  	uint16_t rnmax;
>  	uint8_t rnsize;
> -	uint8_t  _reserved1[16 - 11];       /* 11-15 */
> +	uint8_t  _reserved1[15 - 11];       /* 11-14 */
> +	uint8_t stsi_parm;
>  	uint16_t entries_cpu;               /* 16-17 */
>  	uint16_t offset_cpu;                /* 18-19 */
>  	uint8_t  _reserved2[24 - 20];       /* 20-23 */
> @@ -322,6 +323,7 @@ void sclp_console_setup(void);
>  void sclp_print(const char *str);
>  void sclp_read_info(void);
>  int sclp_get_cpu_num(void);
> +int sclp_get_stsi_parm(void);
>  CPUEntry *sclp_get_cpu_entries(void);
>  void sclp_facilities_setup(void);
>  int sclp_service_call(unsigned int command, void *sccb);