[PATCH 0/6] Support PPTT for ARM64

Jeremy Linton jeremy.linton at arm.com
Thu Sep 14 11:46:48 PDT 2017

ACPI 6.2 adds the Processor Properties Topology Table (PPTT), which is
used to describe the processor and cache topologies. Ideally it is
used to extend/override information provided by the hardware, but
right now ARM64 is entirely dependent on firmware provided tables.

This patch parses the table for the cache topology and CPU topology.
For the latter we also add an additional topology_cod_id() macro,
and a package_id for arm64. Initially the physical id will match
the cluster id, but we update users of the cluster to utilize
the new macro. When we enable PPTT for the arm64 the cluster/socket
starts to differ. Because of this we also make some dynamic decisions
about mapping thread/core/cod/socket to the thread/socket used by the

For example on juno:

[root at mammon-juno-rh topology]# lstopo-no-graphics
Machine (7048MB)
  Package L#0
    L2 L#0 (1024KB) + Core L#0
      L1d L#0 (32KB) + L1i L#0 (32KB) + PU L#0 (P#0)
      L1d L#1 (32KB) + L1i L#1 (32KB) + PU L#1 (P#1)
      L1d L#2 (32KB) + L1i L#2 (32KB) + PU L#2 (P#2)
      L1d L#3 (32KB) + L1i L#3 (32KB) + PU L#3 (P#3)
    L2 L#1 (2048KB) + Core L#1
      L1d L#4 (32KB) + L1i L#4 (48KB) + PU L#4 (P#4)
      L1d L#5 (32KB) + L1i L#5 (48KB) + PU L#5 (P#5)
  HostBridge L#0
          PCI 1095:3132
            Block(Disk) L#0 "sda"
          PCI 1002:68f9
            GPU L#1 "renderD128"
            GPU L#2 "card0"
            GPU L#3 "controlD64"
          PCI 11ab:4380
            Net L#4 "enp8s0"

Jeremy Linton (6):
  ACPI/PPTT: Add Processor Properties Topology Table parsing
  ACPI: Enable PPTT support on ARM64
  drivers: base: cacheinfo: arm64: Add support for ACPI based firmware
  Topology: Add cluster on die macros and arm64 decoding
  arm64: Fixup users of topology_physical_package_id
  arm64: topology: Enable ACPI/PPTT based CPU topology.

 arch/arm64/Kconfig                |   1 +
 arch/arm64/include/asm/topology.h |   4 +-
 arch/arm64/kernel/cacheinfo.c     |  23 +-
 arch/arm64/kernel/topology.c      |  76 +++++-
 drivers/acpi/Makefile             |   1 +
 drivers/acpi/arm64/Kconfig        |   3 +
 drivers/acpi/pptt.c               | 508 ++++++++++++++++++++++++++++++++++++++
 drivers/base/cacheinfo.c          |  17 +-
 drivers/clk/clk-mb86s7x.c         |   2 +-
 drivers/cpufreq/arm_big_little.c  |   2 +-
 drivers/firmware/psci_checker.c   |   2 +-
 include/linux/cacheinfo.h         |  10 +-
 include/linux/topology.h          |   5 +
 13 files changed, 634 insertions(+), 20 deletions(-)
 create mode 100644 drivers/acpi/pptt.c


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