[PATCH v7 05/13] ACPI/PPTT: Add Processor Properties Topology Table parsing

Sudeep Holla sudeep.holla at arm.com
Tue Mar 6 09:39:24 PST 2018



On 28/02/18 22:06, Jeremy Linton wrote:
> ACPI 6.2 adds a new table, which describes how processing units
> are related to each other in tree like fashion. Caches are
> also sprinkled throughout the tree and describe the properties
> of the caches in relation to other caches and processing units.
> 
> Add the code to parse the cache hierarchy and report the total
> number of levels of cache for a given core using
> acpi_find_last_cache_level() as well as fill out the individual
> cores cache information with cache_setup_acpi() once the
> cpu_cacheinfo structure has been populated by the arch specific
> code.
> 
> An additional patch later in the set adds the ability to report
> peers in the topology using find_acpi_cpu_topology()
> to report a unique ID for each processing unit at a given level
> in the tree. These unique id's can then be used to match related
> processing units which exist as threads, COD (clusters
> on die), within a given package, etc.
> 
> 
The more I look at the ACPI table parsing code, I get more questions
every time :). So I just skimmed through it this time. Not sure why
ACPI_PTR_* is not used elsewhere in drivers/acpi/tables.c

Anyways for cacheinfo part of this file:

Acked-by: Sudeep Holla <sudeep.holla at arm.com>

-- 
Regards,
Sudeep



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