[Skiboot] [PATCH v2 5/8] capp/phb4: Force CAPP to PCIe mode during kernel shutdown

[Vaibhav Jain]

Andrew Donnellan <andrew.donnellan at au1.ibm.com> writes:

>> +static bool phb4_host_sync_reset(void *data)
>> +{
>> +	struct phb4 *p = (struct phb4 *)data;
>> +	struct phb *phb = &p->phb;
>> +	int64_t rc = 0;
>> +
>> +	/* Make sure no-one modifies the phb flags while we are active */
>> +	phb_lock(phb);
>> +
>> +	/* Make sure CAPP is attached to the PHB */
>> +	if (phb->capp)
>> +		/* Call phb ops to disable capi */
>> +		rc = phb->ops->set_capi_mode(phb, OPAL_PHB_CAPI_MODE_PCIE,
>> +				       phb->capp->attached_pe);
>> +	else
>> +		rc = OPAL_SUCCESS;
>
> This code is fine, but I'm assuming that set_capi_mode() will still 
> return OPAL_SUCCESS if the CAPP isn't attached, right?

No, with phb->capp un-initialized phb4_set_capi_mode() will return
OPAL_UNSUPPORTED and opal_sync_host_reboot() will return OPAL_BUSY_EVENT
back to kernel which will then continue to call opal_sync_host_reboot()

> ...
>
>>   static int64_t phb4_poll_link(struct pci_slot *slot)
>>   {
>>   	struct phb4 *p = phb_to_phb4(slot->phb);
>> @@ -4419,7 +4450,7 @@ static int64_t phb4_init_capp(struct phb4 *p)
>>   		capp->capp_xscom_offset = CAPP1_REG_OFFSET;
>>   	}
>>   
>> -	capp->attached_pe = phb4_get_reserved_pe_number(phb);
>> +	capp->attached_pe = phb4_get_reserved_pe_number(&p->phb);
>>   
>>   	/* Load capp microcode into the capp unit */
>>   	load_capp_ucode(p);
>> @@ -4462,7 +4493,8 @@ static int64_t phb4_set_capi_mode(struct phb *phb, uint64_t mode,
>>   			break;
>>   		}
>>   
>> -		xscom_read(p->chip_id, CAPP_ERR_STATUS_CTRL + offset, &reg);
>> +		xscom_read(p->chip_id, CAPP_ERR_STATUS_CTRL +
>> +			   capp->capp_xscom_offset, &reg);
>
> These two hunks need to be moved to previous patches - snowpatch is 
> reporting this breaks bisection.
Thanks for pointing this out. I will get it fixed

>
> With that fixed:
>
> Reviewed-by: Andrew Donnellan <andrew.donnellan at au1.ibm.com>
Thanks,


-- 
Vaibhav Jain <vaibhav at linux.ibm.com>
Linux Technology Center, IBM India Pvt. Ltd.