You have been subscribed to a public bug:

== Comment: #0 - Breno Leitao <bren...@br.ibm.com> - 2017-06-19 09:44:36 ==
The P9 PVR bits 12-15 don't indicate a revision but instead different
chip configurations.  From BookIV we have:
   Bits      Configuration
    0 :    Scale out 12 cores
    1 :    Scale out 24 cores
    2 :    Scale up  12 cores
    3 :    Scale up  24 cores

DD1 doesn't use this but DD2 does. Linux will mostly use the "Scale
out 24 core" configuration (ie. SMT4 not SMT8) which results in a PVR
of 0x004e1200. The reported revision in /proc/cpuinfo is hence
reported incorrectly as "18.0".

This patch fixes this to mask off only the relevant bits for the major
revision (ie. bits 8-11) for POWER9.

Please cherry pick: https://patchwork.ozlabs.org/patch/776052/

** Affects: linux (Ubuntu)
     Importance: Undecided
     Assignee: Ubuntu on IBM Power Systems Bug Triage (ubuntu-power-triage)
         Status: New


** Tags: architecture-ppc64le bugnameltc-155824 severity-medium 
targetmilestone-inin16043
-- 
Fix /proc/cpuinfo revision for POWER9 DD2
https://bugs.launchpad.net/bugs/1698844
You received this bug notification because you are a member of Kernel Packages, 
which is subscribed to linux in Ubuntu.

-- 
Mailing list: https://launchpad.net/~kernel-packages
Post to     : kernel-packages@lists.launchpad.net
Unsubscribe : https://launchpad.net/~kernel-packages
More help   : https://help.launchpad.net/ListHelp

Reply via email to