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linux/arch/arm64/kernel/topology.c

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arm64: topology: Implement basic CPU topology support 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>
2014-03-04 07:51:17 +00:00
/*
* arch/arm64/kernel/topology.c
*
* Copyright (C) 2011,2013,2014 Linaro Limited.
*
* Based on the arm32 version written by Vincent Guittot in turn based on
* arch/sh/kernel/topology.c
*
* This file is subject to the terms and conditions of the GNU General Public
* License. See the file "COPYING" in the main directory of this archive
* for more details.
*/
arm64: topology: enable ACPI/PPTT based CPU topology 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>
2018-05-11 23:58:05 +00:00
#include <linux/acpi.h>
arm,arm64,drivers: move externs in a new header file 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>
2017-05-31 16:59:30 +00:00
#include <linux/arch_topology.h>
arm64: topology: divorce MC scheduling domain from core_siblings 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>
2018-05-11 23:58:07 +00:00
#include <linux/cacheinfo.h>
arm64: topology: Implement basic CPU topology support 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>
2014-03-04 07:51:17 +00:00
#include <linux/init.h>
#include <linux/percpu.h>
arm64: add sysfs cpu_capacity attribute 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>
2016-11-03 05:40:18 +00:00
#include <asm/cpu.h>
arm64: topology: add MPIDR-based detection 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>
2014-06-07 00:55:27 +00:00
#include <asm/cputype.h>
arm64: topology: Implement basic CPU topology support 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>
2014-03-04 07:51:17 +00:00
#include <asm/topology.h>
void store_cpu_topology(unsigned int cpuid)
{
arm64: topology: add MPIDR-based detection 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>
2014-06-07 00:55:27 +00:00
struct cpu_topology *cpuid_topo = &cpu_topology[cpuid];
u64 mpidr;
arm64: topology: rename cluster_id 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>
2018-05-11 23:58:04 +00:00
if (cpuid_topo->package_id != -1)
arm64: topology: add MPIDR-based detection 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>
2014-06-07 00:55:27 +00:00
goto topology_populated;
mpidr = read_cpuid_mpidr();
/* Uniprocessor systems can rely on default topology values */
if (mpidr & MPIDR_UP_BITMASK)
return;
/* Create cpu topology mapping based on MPIDR. */
if (mpidr & MPIDR_MT_BITMASK) {
/* Multiprocessor system : Multi-threads per core */
cpuid_topo->thread_id = MPIDR_AFFINITY_LEVEL(mpidr, 0);
cpuid_topo->core_id = MPIDR_AFFINITY_LEVEL(mpidr, 1);
arm64: topology: rename cluster_id 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>
2018-05-11 23:58:04 +00:00
cpuid_topo->package_id = MPIDR_AFFINITY_LEVEL(mpidr, 2) |
arm64: topology: Fix handling of multi-level cluster MPIDR-based detection 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>
2014-11-21 00:36:49 +00:00
MPIDR_AFFINITY_LEVEL(mpidr, 3) << 8;
arm64: topology: add MPIDR-based detection 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>
2014-06-07 00:55:27 +00:00
} else {
/* Multiprocessor system : Single-thread per core */
cpuid_topo->thread_id = -1;
cpuid_topo->core_id = MPIDR_AFFINITY_LEVEL(mpidr, 0);
arm64: topology: rename cluster_id 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>
2018-05-11 23:58:04 +00:00
cpuid_topo->package_id = MPIDR_AFFINITY_LEVEL(mpidr, 1) |
arm64: topology: Fix handling of multi-level cluster MPIDR-based detection 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>
2014-11-21 00:36:49 +00:00
MPIDR_AFFINITY_LEVEL(mpidr, 2) << 8 |
MPIDR_AFFINITY_LEVEL(mpidr, 3) << 16;
arm64: topology: add MPIDR-based detection 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>
2014-06-07 00:55:27 +00:00
}
pr_debug("CPU%u: cluster %d core %d thread %d mpidr %#016llx\n",
arm64: topology: rename cluster_id 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>
2018-05-11 23:58:04 +00:00
cpuid, cpuid_topo->package_id, cpuid_topo->core_id,
arm64: topology: add MPIDR-based detection 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>
2014-06-07 00:55:27 +00:00
cpuid_topo->thread_id, mpidr);
topology_populated:
arm64: topology: Implement basic CPU topology support 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>
2014-03-04 07:51:17 +00:00
update_siblings_masks(cpuid);
}
arm64: topology: enable ACPI/PPTT based CPU topology 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>
2018-05-11 23:58:05 +00:00
#ifdef CONFIG_ACPI
arm64: topology: Use PPTT to determine if PE is a thread ACPI 6.3 adds a thread flag to represent if a CPU/PE is actually a thread. Given that the MPIDR_MT bit may not represent this information consistently on homogeneous machines we should prefer the PPTT flag if its available. Signed-off-by: Jeremy Linton <jeremy.linton@arm.com> Reviewed-by: Sudeep Holla <sudeep.holla@arm.com> Reviewed-by: Robert Richter <rrichter@marvell.com> [will: made acpi_cpu_is_threaded() return 'bool'] Signed-off-by: Will Deacon <will@kernel.org>
2019-08-08 20:40:07 +00:00
static bool __init acpi_cpu_is_threaded(int cpu)
{
int is_threaded = acpi_pptt_cpu_is_thread(cpu);
/*
* if the PPTT doesn't have thread information, assume a homogeneous
* machine and return the current CPU's thread state.
*/
if (is_threaded < 0)
is_threaded = read_cpuid_mpidr() & MPIDR_MT_BITMASK;
return !!is_threaded;
}
arm64: topology: enable ACPI/PPTT based CPU topology 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>
2018-05-11 23:58:05 +00:00
/*
* Propagate the topology information of the processor_topology_node tree to the
* cpu_topology array.
*/
cpu-topology: Move cpu topology code to common code. Both RISC-V & ARM64 are using cpu-map device tree to describe their cpu topology. It's better to move the relevant code to a common place instead of duplicate code. To: Will Deacon <will.deacon@arm.com> To: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Atish Patra <atish.patra@wdc.com> [Tested on QDF2400] Tested-by: Jeffrey Hugo <jhugo@codeaurora.org> [Tested on Juno and other embedded platforms.] Tested-by: Sudeep Holla <sudeep.holla@arm.com> Reviewed-by: Sudeep Holla <sudeep.holla@arm.com> Acked-by: Will Deacon <will.deacon@arm.com> Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Paul Walmsley <paul.walmsley@sifive.com>
2019-06-27 19:52:58 +00:00
int __init parse_acpi_topology(void)
arm64: topology: enable ACPI/PPTT based CPU topology 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>
2018-05-11 23:58:05 +00:00
{
int cpu, topology_id;
cpu-topology: Move cpu topology code to common code. Both RISC-V & ARM64 are using cpu-map device tree to describe their cpu topology. It's better to move the relevant code to a common place instead of duplicate code. To: Will Deacon <will.deacon@arm.com> To: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Atish Patra <atish.patra@wdc.com> [Tested on QDF2400] Tested-by: Jeffrey Hugo <jhugo@codeaurora.org> [Tested on Juno and other embedded platforms.] Tested-by: Sudeep Holla <sudeep.holla@arm.com> Reviewed-by: Sudeep Holla <sudeep.holla@arm.com> Acked-by: Will Deacon <will.deacon@arm.com> Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Paul Walmsley <paul.walmsley@sifive.com>
2019-06-27 19:52:58 +00:00
if (acpi_disabled)
return 0;
arm64: topology: enable ACPI/PPTT based CPU topology 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>
2018-05-11 23:58:05 +00:00
for_each_possible_cpu(cpu) {
arm64: topology: divorce MC scheduling domain from core_siblings 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>
2018-05-11 23:58:07 +00:00
int i, cache_id;
arm64: topology: enable ACPI/PPTT based CPU topology 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>
2018-05-11 23:58:05 +00:00
topology_id = find_acpi_cpu_topology(cpu, 0);
if (topology_id < 0)
return topology_id;
arm64: topology: Use PPTT to determine if PE is a thread ACPI 6.3 adds a thread flag to represent if a CPU/PE is actually a thread. Given that the MPIDR_MT bit may not represent this information consistently on homogeneous machines we should prefer the PPTT flag if its available. Signed-off-by: Jeremy Linton <jeremy.linton@arm.com> Reviewed-by: Sudeep Holla <sudeep.holla@arm.com> Reviewed-by: Robert Richter <rrichter@marvell.com> [will: made acpi_cpu_is_threaded() return 'bool'] Signed-off-by: Will Deacon <will@kernel.org>
2019-08-08 20:40:07 +00:00
if (acpi_cpu_is_threaded(cpu)) {
arm64: topology: enable ACPI/PPTT based CPU topology 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>
2018-05-11 23:58:05 +00:00
cpu_topology[cpu].thread_id = topology_id;
topology_id = find_acpi_cpu_topology(cpu, 1);
cpu_topology[cpu].core_id = topology_id;
} else {
cpu_topology[cpu].thread_id = -1;
cpu_topology[cpu].core_id = topology_id;
}
topology_id = find_acpi_cpu_topology_package(cpu);
cpu_topology[cpu].package_id = topology_id;
arm64: topology: divorce MC scheduling domain from core_siblings 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>
2018-05-11 23:58:07 +00:00
i = acpi_find_last_cache_level(cpu);
if (i > 0) {
/*
* this is the only part of cpu_topology that has
* a direct relationship with the cache topology
*/
cache_id = find_acpi_cpu_cache_topology(cpu, i);
if (cache_id > 0)
cpu_topology[cpu].llc_id = cache_id;
}
arm64: topology: enable ACPI/PPTT based CPU topology 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>
2018-05-11 23:58:05 +00:00
}
return 0;
}
#endif
arm64: topology: Add support for topology DT bindings 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>
2014-05-02 20:38:29 +00:00
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