[Skiboot] [PATCH v8] power-mgmt : occ : Add 'freq-domain-mask' DT property

Stewart Smith stewart at linux.vnet.ibm.com
Tue Feb 26 17:09:30 AEDT 2019

Abhishek Goel <huntbag at linux.vnet.ibm.com> writes:
> Add a new device-tree property freq-domain-indicator to define group of
> CPUs which would share same frequency. This property has been added under
> power-mgmt node. It is a bitmask.
> Bitwise AND is taken between this bitmask value and PIR of cpu. All the
> CPUs lying in the same frequency domain will have same result for AND.
> For example, For POWER9, 0xFFF0 indicates quad wide frequency domain.
> Taking AND with the PIR of CPUs will yield us frequency domain which is
> quad wise distribution as last 4 bits have been masked which represent the
> cores.
> Similarly, 0xFFF8 will represent core wide frequency domain for P8.
> Also, Add a new device-tree property domain-runs-at which will denote the
> strategy OCC is using to change the frequency of a frequency-domain. There
> can be two strategy - FREQ_MOST_RECENTLY_SET and FREQ_MAX_IN_DOMAIN.
> FREQ_MOST_RECENTLY_SET : the OCC sets the frequency of the quad to the most
> recent frequency value requested by the CPUs in the quad.
> FREQ_MAX_IN_DOMAIN : the OCC sets the frequency of the CPUs in
> the Quad to the maximum of the latest frequency requested by each of
> the component cores.

Merged to master as of b821f8c2a8e38c18b0dd976b15f699d243a6099f.

Sorry for the longer-than-ideal delay here.

Stewart Smith
OPAL Architect, IBM.

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