[Skiboot] [PATCH 2/2] occ: Filter out entries from Pmin to Pmax in Pstate table

Shilpasri G Bhat shilpa.bhat at linux.vnet.ibm.com
Fri Nov 6 17:11:33 AEDT 2015

Hi Joel,

On 11/04/2015 08:26 PM, Joel Stanley wrote:
> Hello,
> On Wed, Nov 4, 2015 at 4:40 PM, Shilpasri G Bhat
> <shilpa.bhat at linux.vnet.ibm.com> wrote:
>> Parse the entire pstate table provided by OCC and filter out the
>> entries that are outside the Pmax and Pmin limits.
> Can you explain why we do this in skiboot, instead of the OCC?

Today OCC does not expose pstates outside the limits of the processor to the
host. Psafe which is less than Pmin, is one such pstate that is not exposed to
host. We would want OCC to share the complete pstate table to host for better
reporting. In such cases skiboot should filter the pstate table.

> As I understood it the tables provided to us by the OCC would be
> constructed such that entries are within limits of the processor.

Another case is when OCC would want to increase the pstates in the pstate table
for MFG. Going ahead, the idea is to export the pstates outside the Pmin and
Pmax range separately to host via device tree.

> Cheers,
> Joel
Thanks and Regards,

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