[v6] powerpc/powernv: Add poweroff (EPOW, DPO) events support for PowerNV platform

[Vipin K Parashar]

On 06/05/2015 03:31 AM, Michael Ellerman wrote:
> On Thu, 2015-04-06 at 12:03:17 UTC, Vipin K Parashar wrote:
>> This patch adds support for FSP (Flexible Service Processor)
>> EPOW (Early Power Off Warning) and DPO (Delayed Power Off) events for
>> the PowerNV platform. EPOW events are generated by FSP due to various
>> critical system conditions that require system shutdown. A few examples
>> of these conditions are high ambient temperature or system running on
>> UPS power with low UPS battery. DPO event is generated in response to
>> admin initiated system shutdown request. Upon receipt of EPOW and DPO
>> events the host kernel invokes orderly_poweroff() for performing
>> graceful system shutdown.
>>
>> Reviewed-by: Joel Stanley <joel at jms.id.au>
>> Reviewed-by: Vaibhav Jain <vaibhav at linux.vnet.ibm.com>
>> Reviewed-by: Michael Ellerman <mpe at ellerman.id.au>
>> Signed-off-by: Vipin K Parashar <vipin at linux.vnet.ibm.com>
> Hi Vipin,
>
> One issue, on mambo I'm seeing:
>
>    [666973573,3] OPAL: Called with bad token 105 !
>    opal-power: Existing DPO event detected.
>    reboot: Failed to start orderly shutdown: forcing the issue
>    reboot: Power down
>    [684431322,5] OPAL: Shutdown request type 0x0...
>
>
> ie. at boot it shuts down immediately.
>
> The problem is in here I think:
>
>> +	/* Check for DPO event */
>> +	rc = opal_get_dpo_status(&opal_dpo_timeout);
>> +	if (rc != OPAL_WRONG_STATE) {
>> +		pr_info("Existing DPO event detected.\n");
>> +		return true;
>> +	}

Thanks for catching it. EPOW, DPO doesn't exist for BMC and thus we 
shouldn't
be hitting this path on BMC/mambo. Bug exists below down where we check for
  epow device-tree  node . This bug got introduced with this version of 
patch
when i renamed epow_dpo_supported flag with supported flag and re-organized
code. Will send out fix for this. Above if cond is also isn't prefect so 
will fix it too
with new patch.

For FSP systems please use below FW patch to make it avoid notifications 
which
doesn't cause EPOW. Its already in recent skiboot tree.
Commit id 1954251ca83b8a458193e629d15da06d00643ae8

https://patchwork.ozlabs.org/patch/472303/

>
> This also makes me think you probably haven't tested this on a BMC machine?
>
> cheers
>