[Skiboot] [PATCH] powerpc/powernv: handle OPAL_SUCCESS return in opal_sensor_read

Stewart Smith stewart at linux.vnet.ibm.com
Fri Mar 27 17:05:45 AEDT 2015

Cedric Le Goater <clg at fr.ibm.com> writes:
> The sensor service in OPAL only handles one FSP request at a time and 
> returns OPAL_BUSY if one is already in progress. The lock covers this case 
> but we could also remove it return EBUSY to the driver or even retry the 
> call. That might be dangerous though. 

Retrying the call should be okay.

Just because FSP wants to do things serially doesn't mean non-FSP does :)

> Changing OPAL to handle simultaneously multiple requests does not seem really 
> necessary, it won't speed up the communication with the FSP and that is the
> main bottleneck.

Only on FSP systems though, and all of the OpenPower machines don't have
FSPs :)

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