For upcoming Arm MPAM support in resctrl, it is necessary to have the cacheinfo 'id' for MPAM enabled caches. The 'id' is part of the resctrl ABI. While this support already exists for ACPI based systems, it is missing for DT. This series adds the support. The 'id' value used is the smallest CPU h/w id value associated with a cache. This requires walking the cache hierarchy from every CPU node to get all CPUs associated with a cache. As MPAM also needs to know this, the CPU affinity is also saved to avoid reimplementing and walking the firmware tables again. Patches 1 and 2 are v2 from the prior series[1]. The rest are new. Tested on arm64 with DT. ACPI changes are untested. I don't have a system with an appropriate PPTT nor do I know how to modify ACPI tables. Rob [1] https://lore.kernel.org/all/20211006164332.1981454-1-robh@xxxxxxxxxx/ Rob Herring (6): cacheinfo: Allow for >32-bit cache 'id' cacheinfo: Set cache 'id' based on DT data cacheinfo: Add cpu_affinity_map to store affinity for all CPUs ACPI / PPTT: Populate the cacheinfo.cpu_affinity_map cacheinfo: Use cpu_affinity_map for populating shared_cpu_map cacheinfo: Add cacheinfo_get_cache_affinity() function drivers/acpi/pptt.c | 29 +++++++++++++++-- drivers/base/cacheinfo.c | 65 ++++++++++++++++++++++++++------------- include/linux/cacheinfo.h | 29 +++++++++++++++-- 3 files changed, 97 insertions(+), 26 deletions(-) -- 2.32.0
