[PATCH v2 0/6] Support PPTT for ARM64

Jeremy Linton jeremy.linton at arm.com
Tue Sep 19 11:47:45 PDT 2017


ACPI 6.2 adds the Processor Properties Topology Table (PPTT), which is
used to describe the processor and cache topology. 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 ACPI/PPTT for arm64 we map the socket
to the physical id as the remainder of the kernel expects.

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

v1->v2:

The parser keys off the acpi_pptt_processor node to determine
  unique cache's rather than the acpi_pptt_cache referenced by the
  processor node. This allows PPTT tables which "share" cache nodes
  across cpu nodes despite not being a shared cache.

Normalize the socket, cluster and thread mapping so that they match
  linux's traditional mapping for the physical id, and thread id.
  Adding explicit scheduler knowledge of clusters (rather than just
  their cache sharing attributes) is a subject for a future patch.

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
    tables
  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      |  62 ++++-
 drivers/acpi/Makefile             |   1 +
 drivers/acpi/arm64/Kconfig        |   3 +
 drivers/acpi/pptt.c               | 459 ++++++++++++++++++++++++++++++++++++++
 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          |   4 +
 13 files changed, 570 insertions(+), 20 deletions(-)
 create mode 100644 drivers/acpi/pptt.c

-- 
2.13.5




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