Feature #16405


initial amdzen family 1ah and cpuid support

Added by Robert Mustacchi 2 months ago. Updated about 2 months ago.

driver - device drivers
Start date:
Due date:
% Done:


Estimated time:
Gerrit CR:
External Bug:


As AMD has started publishing family 0x1a support into Linux, we should follow suite initial support for this family. This covers initial cpuid socket and family detection for the system as well as the amdzen nexus driver.

One thing to call out is that the DF memory controller pieces that are added as part of this work, that we call 4D2, are actually things that relate to more than just family 0x1a. We have seen it used in phoenix and other parts.

Actions #1

Updated by Robert Mustacchi 2 months ago

  • Description updated (diff)
Actions #2

Updated by Electric Monk 2 months ago

  • Gerrit CR set to 3378
Actions #3

Updated by Robert Mustacchi about 2 months ago

To test this I used a system that had the newer CPU and verified that the cpuid revision information all added up (performed via mdb -k and the later topo info), that we had identified the socket type correctly (psrinfo -vp), that the amdzen nexus driver correctly attached, identified the correct DF revision, and the the machinery all worked for the topology information. I manually exercised the umsn and udf machinery and we programmatically consume it for the topo information. With the topo information, I manually verified that the core and cache information looked accurate.

To help regression test this I used the same modified zen module for i86pc (no mods needed for the Oxide system) and verified that we could see the topo information and related on the following systems:

  • AMD Zen 2 Rome
  • AMD Zen 3 Vermeer (client) and an Oxide-based Milan system
  • AMD Zen 4 Raphael (client)
Actions #4

Updated by Electric Monk about 2 months ago

  • Status changed from New to Closed
  • % Done changed from 0 to 100

git commit 019df03d95e2a1cb86c73dd53255176f9611836a

commit  019df03d95e2a1cb86c73dd53255176f9611836a
Author: Robert Mustacchi <>
Date:   2024-04-08T21:42:53.000Z

    16407 Raphael DF revision detection is incorrect
    16405 initial amdzen family 1ah and cpuid support
    16406 zen topo should tolerate missing revision or ppin info
    Reviewed by: Andy Fiddaman <>
    Reviewed by: Luqman Aden <>
    Approved by: Richard Lowe <>


Also available in: Atom PDF