Re: [PATCH v3 0/7] Support PPTT for ARM64

From: John Garry
Date: Fri Oct 13 2017 - 07:09:03 EST


On 12/10/2017 20:48, Jeremy Linton wrote:
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.


Hi Jeremy,

Can you put this series on a public branch for convenience of review and test?

Also, what is your idea for supporting Type 2 ID structure?

Cheers,
John

For example on juno:
[root@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"

v2->v3:

Remove valid bit check on leaf nodes. Now simply being a leaf node
is sufficient to verify the processor id against the ACPI
processor ids (gotten from MADT).

Use the acpi processor for the "level 0" Id. This makes the /sys
visible core/thread ids more human readable if the firmware uses
small consecutive values for processor ids.

Added PPTT to the list of injectable ACPI tables.

Fix bug which kept the code from using the processor node as intended
in v2, caused by misuse of git rebase/fixup.

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 (7):
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.
ACPI: Add PPTT to injectable table list

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 | 486 ++++++++++++++++++++++++++++++++++++++
drivers/acpi/tables.c | 3 +-
drivers/base/cacheinfo.c | 17 +-
drivers/cpufreq/arm_big_little.c | 2 +-
drivers/firmware/psci_checker.c | 2 +-
include/linux/cacheinfo.h | 11 +-
include/linux/topology.h | 4 +
13 files changed, 599 insertions(+), 20 deletions(-)
create mode 100644 drivers/acpi/pptt.c