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

[Jeremy Linton <jeremy.linton@arm.com>]

Hi,

On 10/13/2017 06:08 AM, John Garry wrote:
> 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?

Let me see what I can do..

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

I don't have any plans, as you can see the current patches ignore the ID 
nodes. It should be fairly easy to mine the information from the tables, 
but what parts are necessary or where to use them isn't clear to me.

Suggestions welcome.


> 
> 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
>>
> 
>