[Skiboot] [PATCH v4 5/8] SLW: Configure self-restore for HRMOR

[Vaidyanathan Srinivasan]

* Akshay Adiga <akshay.adiga at linux.vnet.ibm.com> [2017-09-15 13:04:33]:

> Make a stop api call using libpore to restore HRMOR register. HRMOR needs
> to be cleared so that when thread exits stop, they arrives at linux
> system_reset vector (0x100).
> 
> Signed-off-by: Akshay Adiga <akshay.adiga at linux.vnet.ibm.com>

Reviewed-by: Vaidyanathan Srinivasan <svaidy at linux.vnet.ibm.com>

> ---
>  hw/slw.c | 29 +++++++++++++++++++++++++++++
>  1 file changed, 29 insertions(+)
> 
> diff --git a/hw/slw.c b/hw/slw.c
> index a1ed7ba..39aa4d0 100644
> --- a/hw/slw.c
> +++ b/hw/slw.c
> @@ -1254,12 +1254,41 @@ static void slw_patch_regs(struct proc_chip *chip)
>  static void slw_init_chip_p9(struct proc_chip *chip)
>  {
>  	struct cpu_thread *c;
> +	int rc;
> 
>  	prlog(PR_DEBUG, "SLW: Init chip 0x%x\n", chip->id);
> 
>  	/* At power ON setup inits for power-mgt */
>  	for_each_available_core_in_chip(c, chip->id)
>  		slw_set_overrides_p9(chip, c);
> +
> +	if (!chip->homer_base) {
> +		log_simple_error(&e_info(OPAL_RC_SLW_REG),
> +				 "SLW: HOMER base not set %x\n",
> +				 chip->id);
> +		return;
> +	}
> +
> +	prlog(PR_NOTICE, "SLW: Configuring self-restore for HRMOR\n");
> +
> +	/* Should this be for_each_present_cpu() ? */
> +	for_each_available_cpu(c) {
> +		if (c->chip_id != chip->id)
> +			continue;
> +
> +		/*
> +		 * Clear HRMOR. Need to update only for thread
> +		 * 0 of each core. Doing it anyway for all threads
> +		 */
> +		rc =  p9_stop_save_cpureg((void *)chip->homer_base,
> +						P9_STOP_SPR_HRMOR, 0,
> +					       c->pir);
> +		if (rc) {
> +			log_simple_error(&e_info(OPAL_RC_SLW_REG),
> +				 "SLW: Failed to set HRMOR for CPU %x,RC=0x%x\n",
> +				 c->pir, rc);
> +		}
> +	}
>  }
>  static void slw_init_chip(struct proc_chip *chip)
>  {
> -- 
> 2.5.5
>