Public bug reported: == Comment: #0 - Breno Leitao <[email protected]> - 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 ** Tags added: architecture-ppc64le bugnameltc-155824 severity-medium targetmilestone-inin16043 ** Changed in: ubuntu Assignee: (unassigned) => Ubuntu on IBM Power Systems Bug Triage (ubuntu-power-triage) ** Package changed: ubuntu => linux (Ubuntu) -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1698844 Title: Fix /proc/cpuinfo revision for POWER9 DD2 To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1698844/+subscriptions -- ubuntu-bugs mailing list [email protected] https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
