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2018-07-06arm64: topology: re-introduce numa mask check for scheduler MC selectionSudeep Holla1-1/+6
Commit 37c3ec2d810f ("arm64: topology: divorce MC scheduling domain from core_siblings") selected the smallest of LLC, socket siblings, and NUMA node siblings to ensure that the sched domain we build for the MC layer isn't larger than the DIE above it or it's shrunk to the socket or NUMA node if LLC exist acrosis NUMA node/chiplets. Commit acd32e52e4e0 ("arm64: topology: Avoid checking numa mask for scheduler MC selection") reverted the NUMA siblings checks since the CPU topology masks weren't updated on hotplug at that time. This patch re-introduces numa mask check as the CPU and NUMA topology is now updated in hotplug paths. Effectively, this patch does the partial revert of commit acd32e52e4e0. Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Will Deacon <will.deacon@arm.com> Tested-by: Ganapatrao Kulkarni <ganapatrao.kulkarni@cavium.com> Tested-by: Hanjun Guo <hanjun.guo@linaro.org> Signed-off-by: Sudeep Holla <sudeep.holla@arm.com> Signed-off-by: Will Deacon <will.deacon@arm.com>
2018-07-06arm64: topology: rename llc_siblings to align with other struct membersSudeep Holla1-6/+6
Similar to core_sibling and thread_sibling, it's better to align and rename llc_siblings to llc_sibling. Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Will Deacon <will.deacon@arm.com> Tested-by: Ganapatrao Kulkarni <ganapatrao.kulkarni@cavium.com> Tested-by: Hanjun Guo <hanjun.guo@linaro.org> Signed-off-by: Sudeep Holla <sudeep.holla@arm.com> Signed-off-by: Will Deacon <will.deacon@arm.com>
2018-07-06arm64: topology: restrict updating siblings_masks to online cpus onlySudeep Holla1-5/+3
It's incorrect to iterate over all the possible CPUs to update the sibling masks when any CPU is hotplugged in. In case the topology siblings masks of the CPU is removed when is it hotplugged out, we end up updating those masks when one of it's sibling is powered up again. This will provide inconsistent view. Further, since the CPU calling update_sibling_masks is yet to be set online, there's no need to compare itself with each online CPU when updating the siblings masks. This patch restricts updation of sibling masks only for CPUs that are already online. It also the drops the unnecessary cpuid check. Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Will Deacon <will.deacon@arm.com> Tested-by: Ganapatrao Kulkarni <ganapatrao.kulkarni@cavium.com> Tested-by: Hanjun Guo <hanjun.guo@linaro.org> Signed-off-by: Sudeep Holla <sudeep.holla@arm.com> Signed-off-by: Will Deacon <will.deacon@arm.com>
2018-07-06arm64: topology: add support to remove cpu topology sibling masksSudeep Holla1-0/+14
This patch adds support to remove all the CPU topology information using clear_cpu_topology and also resetting the sibling information on other sibling CPUs. This will be used in cpu_disable so that all the topology sibling information is removed on CPU hotplug out. Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Will Deacon <will.deacon@arm.com> Tested-by: Ganapatrao Kulkarni <ganapatrao.kulkarni@cavium.com> Tested-by: Hanjun Guo <hanjun.guo@linaro.org> Signed-off-by: Sudeep Holla <sudeep.holla@arm.com> Signed-off-by: Will Deacon <will.deacon@arm.com>
2018-07-06arm64: topology: refactor reset_cpu_topology to add support for removing topologySudeep Holla1-7/+14
Currently reset_cpu_topology clears all the CPU topology information and resets to default values. However we may need to just clear the information when we hotplug out the CPU. In preparation to add the support the same, let's refactor reset_cpu_topology to just reset the information and move clearing out the topology information to clear_cpu_topology. Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Will Deacon <will.deacon@arm.com> Tested-by: Ganapatrao Kulkarni <ganapatrao.kulkarni@cavium.com> Tested-by: Hanjun Guo <hanjun.guo@linaro.org> Signed-off-by: Sudeep Holla <sudeep.holla@arm.com> Signed-off-by: Will Deacon <will.deacon@arm.com>
2018-06-07arm64: topology: Avoid checking numa mask for scheduler MC selectionJeremy Linton1-7/+4
The numa mask subset check can often lead to system hang or crash during CPU hotplug and system suspend operation if NUMA is disabled. This is mostly observed on HMP systems where the CPU compute capacities are different and ends up in different scheduler domains. Since cpumask_of_node is returned instead core_sibling, the scheduler is confused with incorrect cpumasks(e.g. one CPU in two different sched domains at the same time) on CPU hotplug. Lets disable the NUMA siblings checks for the time being, as NUMA in socket machines have LLC's that will assure that the scheduler topology isn't "borken". The NUMA check exists to assure that if a LLC within a socket crosses NUMA nodes/chiplets the scheduler domains remain consistent. This code will likely have to be re-enabled in the near future once the NUMA mask story is sorted. At the moment its not necessary because the NUMA in socket machines LLC's are contained within the NUMA domains. Further, as a defensive mechanism during hot-plug, lets assure that the LLC siblings are also masked. Reported-by: Geert Uytterhoeven <geert@linux-m68k.org> Reviewed-by: Sudeep Holla <sudeep.holla@arm.com> Tested-by: Geert Uytterhoeven <geert+renesas@glider.be> Signed-off-by: Jeremy Linton <jeremy.linton@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2018-05-17arm64: topology: divorce MC scheduling domain from core_siblingsJeremy Linton1-1/+35
Now that we have an accurate view of the physical topology we need to represent it correctly to the scheduler. Generally MC should equal the LLC in the system, but there are a number of special cases that need to be dealt with. In the case of NUMA in socket, we need to assure that the sched domain we build for the MC layer isn't larger than the DIE above it. Similarly for LLC's that might exist in cross socket interconnect or directory hardware we need to assure that MC is shrunk to the socket or NUMA node. This patch builds a sibling mask for the LLC, and then picks the smallest of LLC, socket siblings, or NUMA node siblings, which gives us the behavior described above. This is ever so slightly different than the similar alternative where we look for a cache layer less than or equal to the socket/NUMA siblings. The logic to pick the MC layer affects all arm64 machines, but only changes the behavior for DT/MPIDR systems if the NUMA domain is smaller than the core siblings (generally set to the cluster). Potentially this fixes a possible bug in DT systems, but really it only affects ACPI systems where the core siblings is correctly set to the socket siblings. Thus all currently available ACPI systems should have MC equal to LLC, including the NUMA in socket machines where the LLC is partitioned between the NUMA nodes. Tested-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Tested-by: Vijaya Kumar K <vkilari@codeaurora.org> Tested-by: Xiongfeng Wang <wangxiongfeng2@huawei.com> Tested-by: Tomasz Nowicki <Tomasz.Nowicki@cavium.com> Acked-by: Sudeep Holla <sudeep.holla@arm.com> Acked-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Acked-by: Morten Rasmussen <morten.rasmussen@arm.com> Signed-off-by: Jeremy Linton <jeremy.linton@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2018-05-17arm64: topology: enable ACPI/PPTT based CPU topologyJeremy Linton1-1/+44
Propagate the topology information from the PPTT tree to the cpu_topology array. We can get the thread id and core_id by assuming certain levels of the PPTT tree correspond to those concepts. The package_id is flagged in the tree and can be found by calling find_acpi_cpu_topology_package() which terminates its search when it finds an ACPI node flagged as the physical package. If the tree doesn't contain enough levels to represent all of the requested levels then the root node will be returned for all subsequent levels. Tested-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Tested-by: Vijaya Kumar K <vkilari@codeaurora.org> Tested-by: Xiongfeng Wang <wangxiongfeng2@huawei.com> Tested-by: Tomasz Nowicki <Tomasz.Nowicki@cavium.com> Acked-by: Sudeep Holla <sudeep.holla@arm.com> Acked-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Acked-by: Morten Rasmussen <morten.rasmussen@arm.com> Signed-off-by: Jeremy Linton <jeremy.linton@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2018-05-17arm64: topology: rename cluster_idJeremy Linton1-13/+13
The cluster concept isn't architecturally defined for arm64. Lets match the name of the arm64 topology field to the kernel macro that uses it. Tested-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Tested-by: Vijaya Kumar K <vkilari@codeaurora.org> Tested-by: Xiongfeng Wang <wangxiongfeng2@huawei.com> Tested-by: Tomasz Nowicki <Tomasz.Nowicki@cavium.com> Acked-by: Sudeep Holla <sudeep.holla@arm.com> Acked-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Acked-by: Morten Rasmussen <morten.rasmussen@arm.com> Signed-off-by: Jeremy Linton <jeremy.linton@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2018-01-02arm64: Use of_cpu_node_to_id helper for CPU topology parsingSuzuki K Poulose1-10/+6
Make use of the new generic helper to convert an of_node of a CPU to the logical CPU id in parsing the topology. Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Leo Yan <leo.yan@linaro.org> Cc: Will Deacon <will.deacon@arm.com> Acked-by: Mark Rutland <mark.rutland@arm.com> Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com> Signed-off-by: Will Deacon <will.deacon@arm.com>
2017-07-20arm64: Convert to using %pOF instead of full_nameRob Herring1-11/+11
Now that we have a custom printf format specifier, convert users of full_name to use %pOF instead. This is preparation to remove storing of the full path string for each node. Signed-off-by: Rob Herring <robh@kernel.org> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Will Deacon <will.deacon@arm.com> Cc: linux-arm-kernel@lists.infradead.org Signed-off-by: Will Deacon <will.deacon@arm.com>
2017-06-03arm,arm64,drivers: add a prefix to drivers arch_topology interfacesJuri Lelli1-2/+2
Now that some functions that deal with arch topology information live under drivers, there is a clash of naming that might create confusion. Tidy things up by creating a topology namespace for interfaces used by arch code; achieve this by prepending a 'topology_' prefix to driver interfaces. Signed-off-by: Juri Lelli <juri.lelli@arm.com> Acked-by: Russell King <rmk+kernel@armlinux.org.uk> Acked-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-06-03arm,arm64,drivers: move externs in a new header fileJuri Lelli1-3/+1
Create a new header file (include/linux/arch_topology.h) and put there declarations of interfaces used by arm, arm64 and drivers code. Signed-off-by: Juri Lelli <juri.lelli@arm.com> Acked-by: Russell King <rmk+kernel@armlinux.org.uk> Acked-by: Catalin Marinas <catalin.marinas@arm.com> Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-06-03arm,arm64,drivers: reduce scope of cap_parsing_failedJuri Lelli1-4/+1
Reduce the scope of cap_parsing_failed (making it static in drivers/base/arch_topology.c) by slightly changing {arm,arm64} DT parsing code. For arm checking for !cap_parsing_failed before calling normalize_ cpu_capacity() is superfluous, as returning an error from parse_ cpu_capacity() (above) means cap_from _dt is set to false. For arm64 we can simply check if raw_capacity points to something, which is not if capacity parsing has failed. Suggested-by: Morten Rasmussen <morten.rasmussen@arm.com> Signed-off-by: Juri Lelli <juri.lelli@arm.com> Acked-by: Russell King <rmk+kernel@armlinux.org.uk> Acked-by: Catalin Marinas <catalin.marinas@arm.com> Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-06-03arm, arm64: factorize common cpu capacity default codeJuri Lelli1-216/+3
arm and arm64 share lot of code relative to parsing CPU capacity information from DT, using that information for appropriate scaling and exposing a sysfs interface for chaging such values at runtime. Factorize such code in a common place (driver/base/arch_topology.c) in preparation for further additions. Suggested-by: Will Deacon <will.deacon@arm.com> Suggested-by: Mark Rutland <mark.rutland@arm.com> Suggested-by: Catalin Marinas <catalin.marinas@arm.com> Cc: Russell King <linux@armlinux.org.uk> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Will Deacon <will.deacon@arm.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Juri Lelli <juri.lelli@arm.com> Acked-by: Russell King <rmk+kernel@armlinux.org.uk> Acked-by: Catalin Marinas <catalin.marinas@arm.com> Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-03-02sched/headers: Prepare for new header dependencies before moving code to <linux/sched/topology.h>Ingo Molnar1-0/+1
We are going to split <linux/sched/topology.h> out of <linux/sched.h>, which will have to be picked up from other headers and a couple of .c files. Create a trivial placeholder <linux/sched/topology.h> file that just maps to <linux/sched.h> to make this patch obviously correct and bisectable. Include the new header in the files that are going to need it. Acked-by: Linus Torvalds <torvalds@linux-foundation.org> Cc: Mike Galbraith <efault@gmx.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-kernel@vger.kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-02-22Merge tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linuxLinus Torvalds1-2/+0
Pull arm64 updates from Will Deacon: - Errata workarounds for Qualcomm's Falkor CPU - Qualcomm L2 Cache PMU driver - Qualcomm SMCCC firmware quirk - Support for DEBUG_VIRTUAL - CPU feature detection for userspace via MRS emulation - Preliminary work for the Statistical Profiling Extension - Misc cleanups and non-critical fixes * tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux: (74 commits) arm64/kprobes: consistently handle MRS/MSR with XZR arm64: cpufeature: correctly handle MRS to XZR arm64: traps: correctly handle MRS/MSR with XZR arm64: ptrace: add XZR-safe regs accessors arm64: include asm/assembler.h in entry-ftrace.S arm64: fix warning about swapper_pg_dir overflow arm64: Work around Falkor erratum 1003 arm64: head.S: Enable EL1 (host) access to SPE when entered at EL2 arm64: arch_timer: document Hisilicon erratum 161010101 arm64: use is_vmalloc_addr arm64: use linux/sizes.h for constants arm64: uaccess: consistently check object sizes perf: add qcom l2 cache perf events driver arm64: remove wrong CONFIG_PROC_SYSCTL ifdef ARM: smccc: Update HVC comment to describe new quirk parameter arm64: do not trace atomic operations ACPI/IORT: Fix the error return code in iort_add_smmu_platform_device() ACPI/IORT: Fix iort_node_get_id() mapping entries indexing arm64: mm: enable CONFIG_HOLES_IN_ZONE for NUMA perf: xgene: Include module.h ...
2017-02-08arm64: remove wrong CONFIG_PROC_SYSCTL ifdefJuri Lelli1-2/+0
The sysfs cpu_capacity entry for each CPU has nothing to do with PROC_FS, nor it's in /proc/sys path. Remove such ifdef. Cc: Will Deacon <will.deacon@arm.com> Cc: Catalin Marinas <catalin.marinas@arm.com> Reported-and-suggested-by: Sudeep Holla <sudeep.holla@arm.com> Fixes: be8f185d8af4 ('arm64: add sysfs cpu_capacity attribute') Signed-off-by: Juri Lelli <juri.lelli@arm.com> Signed-off-by: Will Deacon <will.deacon@arm.com>
2017-01-27arm64: skip register_cpufreq_notifier on ACPI-based systemsPrashanth Prakash1-1/+7
On ACPI based systems where the topology is setup using the API store_cpu_topology, at the moment we do not have necessary code to parse cpu capacity and handle cpufreq notifier, thus resulting in a kernel panic. Stack: init_cpu_capacity_callback+0xb4/0x1c8 notifier_call_chain+0x5c/0xa0 __blocking_notifier_call_chain+0x58/0xa0 blocking_notifier_call_chain+0x3c/0x50 cpufreq_set_policy+0xe4/0x328 cpufreq_init_policy+0x80/0x100 cpufreq_online+0x418/0x710 cpufreq_add_dev+0x118/0x180 subsys_interface_register+0xa4/0xf8 cpufreq_register_driver+0x1c0/0x298 cppc_cpufreq_init+0xdc/0x1000 [cppc_cpufreq] do_one_initcall+0x5c/0x168 do_init_module+0x64/0x1e4 load_module+0x130c/0x14d0 SyS_finit_module+0x108/0x120 el0_svc_naked+0x24/0x28 Fixes: 7202bde8b7ae ("arm64: parse cpu capacity-dmips-mhz from DT") Acked-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Prashanth Prakash <pprakash@codeaurora.org> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2016-11-07arm64: add sysfs cpu_capacity attributeJuri Lelli1-0/+64
Add a sysfs cpu_capacity attribute with which it is possible to read and write (thus over-writing default values) CPUs capacity. This might be useful in situations where values needs changing after boot. The new attribute shows up as: /sys/devices/system/cpu/cpu*/cpu_capacity Cc: Will Deacon <will.deacon@arm.com> Cc: Mark Brown <broonie@kernel.org> Cc: Sudeep Holla <sudeep.holla@arm.com> Signed-off-by: Juri Lelli <juri.lelli@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2016-11-07arm64: parse cpu capacity-dmips-mhz from DTJuri Lelli1-1/+158
With the introduction of cpu capacity-dmips-mhz bindings, CPU capacities can now be calculated from values extracted from DT and information coming from cpufreq. Add parsing of DT information at boot time, and complement it with cpufreq information. Also, store such information using per CPU variables, as we do for arm. Caveat: the information provided by this patch will start to be used in the future. We need to #define arch_scale_cpu_capacity to something provided in arch, so that scheduler's default implementation (which gets used if arch_scale_cpu_capacity is not defined) is overwritten. Cc: Will Deacon <will.deacon@arm.com> Cc: Mark Brown <broonie@kernel.org> Cc: Sudeep Holla <sudeep.holla@arm.com> Signed-off-by: Juri Lelli <juri.lelli@arm.com> Acked-by: Vincent Guittot <vincent.guittot@linaro.org> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2015-07-27arm64: kernel: remove non-legit DT warnings when booting using ACPISudeep Holla1-1/+1
Since both CONFIG_ACPI and CONFIG_OF are enabled when booting using ACPI tables on ARM64 platforms, we get few device tree warnings which are not valid for ACPI boot. We can use of_have_populated_dt to check if the device tree is populated or not before throwing out those errors. This patch uses of_have_populated_dt to remove non legitimate device tree warning when booting using ACPI tables. Cc: Lorenzo Pieralisi <Lorenzo.Pieralisi@arm.com> Acked-by: Catalin Marinas <catalin.marinas@arm.com> Acked-by: Mark Rutland <mark.rutland@arm.com> Signed-off-by: Sudeep Holla <sudeep.holla@arm.com> Signed-off-by: Will Deacon <will.deacon@arm.com>
2014-11-25arm64: topology: Fix handling of multi-level cluster MPIDR-based detectionMark Brown1-2/+5
The only requirement the scheduler has on cluster IDs is that they must be unique. When enumerating the topology based on MPIDR information the kernel currently generates cluster IDs by using the first level of affinity above the core ID (either level one or two depending on if the core has multiple threads) however the ARMv8 architecture allows for up to three levels of affinity. This means that an ARMv8 system may contain cores which have MPIDRs identical other than affinity level three which with current code will cause us to report multiple cores with the same identification to the scheduler in violation of its uniqueness requirement. Ensure that we do not violate the scheduler requirements on systems that uses all the affinity levels by incorporating both affinity levels two and three into the cluser ID when the cores are not threaded. While no currently known hardware uses multi-level clusters it is better to program defensively, this will help ease bringup of systems that have them and will ensure that things like distribution install media do not need to be respun to replace kernels in order to deploy such systems. In the worst case the system will work but perform suboptimally until a kernel modified to handle the new topology better is installed, in the best case this will be an adequate description of such topologies for the scheduler to perform well. Signed-off-by: Mark Brown <broonie@linaro.org> Signed-off-by: Will Deacon <will.deacon@arm.com>
2014-07-09arm64: topology: add MPIDR-based detectionZi Shen Lim1-14/+33
Create cpu topology based on MPIDR. When hardware sets MPIDR to sane values, this method will always work. Therefore it should also work well as the fallback method. [1] When we have multiple processing elements in the system, we create the cpu topology by mapping each affinity level (from lowest to highest) to threads (if they exist), cores, and clusters. [1] http://www.spinics.net/lists/arm-kernel/msg317445.html Acked-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com> Signed-off-by: Zi Shen Lim <zlim@broadcom.com> Signed-off-by: Mark Brown <broonie@linaro.org> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2014-05-16arm64: topology: Add support for topology DT bindingsMark Brown1-8/+196
Add support for parsing the explicit topology bindings to discover the topology of the system. Since it is not currently clear how to map multi-level clusters for the scheduler all leaf clusters are presented to the scheduler at the same level. This should be enough to provide good support for current systems. Signed-off-by: Mark Brown <broonie@linaro.org> Reviewed-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2014-05-16arm64: topology: Initialise default topology state immediatelyMark Brown1-4/+4
As a legacy of the way 32 bit ARM did things the topology code uses a null topology map by default and then overwrites it by mapping cores with no information to a cluster by themselves later. In order to make it simpler to reset things as part of recovering from parse failures in firmware information directly set this configuration on init. A core will always be its own sibling so there should be no risk of confusion with firmware provided information. Signed-off-by: Mark Brown <broonie@linaro.org> Reviewed-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2014-03-04arm64: topology: Implement basic CPU topology supportMark Brown1-0/+95
Add basic CPU topology support to arm64, based on the existing pre-v8 code and some work done by Mark Hambleton. This patch does not implement any topology discovery support since that should be based on information from firmware, it merely implements the scaffolding for integration of topology support in the architecture. No locking of the topology data is done since it is only modified during CPU bringup with external serialisation from the SMP code. The goal is to separate the architecture hookup for providing topology information from the DT parsing in order to ease review and avoid blocking the architecture code (which will be built on by other work) with the DT code review by providing something simple and basic. Following patches will implement support for interpreting topology information from MPIDR and for parsing the DT topology bindings for ARM, similar patches will be needed for ACPI. Signed-off-by: Mark Brown <broonie@linaro.org> Acked-by: Mark Rutland <mark.rutland@arm.com> [catalin.marinas@arm.com: removed CONFIG_CPU_TOPOLOGY, always on if SMP] Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>