Re: [RESEND PATCH v2 2/3] powerpc/powernv: Introduce Self save support

[Ram Pai <linuxram@us.ibm.com>]

On Mon, Jan 13, 2020 at 09:15:08AM +0530, Pratik Rajesh Sampat wrote:
> This commit introduces and leverages the Self save API which OPAL now
> supports.
> 
> Add the new Self Save OPAL API call in the list of OPAL calls.
> Implement the self saving of the SPRs based on the support populated
> while respecting it's preferences.
> 
> This implementation allows mixing of support for the SPRs, which
> means that a SPR can be self restored while another SPR be self saved if
> they support and prefer it to be so.
> 
> Signed-off-by: Pratik Rajesh Sampat <psampat@linux.ibm.com>
> ---
>  arch/powerpc/include/asm/opal-api.h        | 3 ++-
>  arch/powerpc/include/asm/opal.h            | 1 +
>  arch/powerpc/platforms/powernv/idle.c      | 2 ++
>  arch/powerpc/platforms/powernv/opal-call.c | 1 +
>  4 files changed, 6 insertions(+), 1 deletion(-)
> 
> diff --git a/arch/powerpc/include/asm/opal-api.h b/arch/powerpc/include/asm/opal-api.h
> index c1f25a760eb1..1b6e1a68d431 100644
> --- a/arch/powerpc/include/asm/opal-api.h
> +++ b/arch/powerpc/include/asm/opal-api.h
> @@ -214,7 +214,8 @@
>  #define OPAL_SECVAR_GET				176
>  #define OPAL_SECVAR_GET_NEXT			177
>  #define OPAL_SECVAR_ENQUEUE_UPDATE		178
> -#define OPAL_LAST				178
> +#define OPAL_SLW_SELF_SAVE_REG			181
> +#define OPAL_LAST				181
> 
>  #define QUIESCE_HOLD			1 /* Spin all calls at entry */
>  #define QUIESCE_REJECT			2 /* Fail all calls with OPAL_BUSY */
> diff --git a/arch/powerpc/include/asm/opal.h b/arch/powerpc/include/asm/opal.h
> index 9986ac34b8e2..389a85b63805 100644
> --- a/arch/powerpc/include/asm/opal.h
> +++ b/arch/powerpc/include/asm/opal.h
> @@ -203,6 +203,7 @@ int64_t opal_handle_hmi(void);
>  int64_t opal_handle_hmi2(__be64 *out_flags);
>  int64_t opal_register_dump_region(uint32_t id, uint64_t start, uint64_t end);
>  int64_t opal_unregister_dump_region(uint32_t id);
> +int64_t opal_slw_self_save_reg(uint64_t cpu_pir, uint64_t sprn);
>  int64_t opal_slw_set_reg(uint64_t cpu_pir, uint64_t sprn, uint64_t val);
>  int64_t opal_config_cpu_idle_state(uint64_t state, uint64_t flag);
>  int64_t opal_pci_set_phb_cxl_mode(uint64_t phb_id, uint64_t mode, uint64_t pe_number);
> diff --git a/arch/powerpc/platforms/powernv/idle.c b/arch/powerpc/platforms/powernv/idle.c
> index 2f328403b0dc..d67d4d0b169b 100644
> --- a/arch/powerpc/platforms/powernv/idle.c
> +++ b/arch/powerpc/platforms/powernv/idle.c
> @@ -1172,6 +1172,8 @@ void pnv_program_cpu_hotplug_lpcr(unsigned int cpu, u64 lpcr_val)
>  		if (!is_lpcr_self_save)
>  			opal_slw_set_reg(pir, SPRN_LPCR,
>  					 lpcr_val);
> +		else
> +			opal_slw_self_save_reg(pir, SPRN_LPCR);

opal_slw_self_save_reg() was used in the prior patch too. How did it
compile, if the definition is in this patch?


Reviewed-by: Ram Pai <linuxram@us.ibm.com>

RP