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authorLibravatar Linus Torvalds <torvalds@linux-foundation.org>2023-02-21 18:24:12 -0800
committerLibravatar Linus Torvalds <torvalds@linux-foundation.org>2023-02-21 18:24:12 -0800
commit5b7c4cabbb65f5c469464da6c5f614cbd7f730f2 (patch)
treecc5c2d0a898769fd59549594fedb3ee6f84e59a0 /Documentation/devicetree/bindings/cpu/cpu-topology.txt
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Merge tag 'net-next-6.3' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-nextgrafted
Pull networking updates from Jakub Kicinski: "Core: - Add dedicated kmem_cache for typical/small skb->head, avoid having to access struct page at kfree time, and improve memory use. - Introduce sysctl to set default RPS configuration for new netdevs. - Define Netlink protocol specification format which can be used to describe messages used by each family and auto-generate parsers. Add tools for generating kernel data structures and uAPI headers. - Expose all net/core sysctls inside netns. - Remove 4s sleep in netpoll if carrier is instantly detected on boot. - Add configurable limit of MDB entries per port, and port-vlan. - Continue populating drop reasons throughout the stack. - Retire a handful of legacy Qdiscs and classifiers. Protocols: - Support IPv4 big TCP (TSO frames larger than 64kB). - Add IP_LOCAL_PORT_RANGE socket option, to control local port range on socket by socket basis. - Track and report in procfs number of MPTCP sockets used. - Support mixing IPv4 and IPv6 flows in the in-kernel MPTCP path manager. - IPv6: don't check net.ipv6.route.max_size and rely on garbage collection to free memory (similarly to IPv4). - Support Penultimate Segment Pop (PSP) flavor in SRv6 (RFC8986). - ICMP: add per-rate limit counters. - Add support for user scanning requests in ieee802154. - Remove static WEP support. - Support minimal Wi-Fi 7 Extremely High Throughput (EHT) rate reporting. - WiFi 7 EHT channel puncturing support (client & AP). BPF: - Add a rbtree data structure following the "next-gen data structure" precedent set by recently added linked list, that is, by using kfunc + kptr instead of adding a new BPF map type. - Expose XDP hints via kfuncs with initial support for RX hash and timestamp metadata. - Add BPF_F_NO_TUNNEL_KEY extension to bpf_skb_set_tunnel_key to better support decap on GRE tunnel devices not operating in collect metadata. - Improve x86 JIT's codegen for PROBE_MEM runtime error checks. - Remove the need for trace_printk_lock for bpf_trace_printk and bpf_trace_vprintk helpers. - Extend libbpf's bpf_tracing.h support for tracing arguments of kprobes/uprobes and syscall as a special case. - Significantly reduce the search time for module symbols by livepatch and BPF. - Enable cpumasks to be used as kptrs, which is useful for tracing programs tracking which tasks end up running on which CPUs in different time intervals. - Add support for BPF trampoline on s390x and riscv64. - Add capability to export the XDP features supported by the NIC. - Add __bpf_kfunc tag for marking kernel functions as kfuncs. - Add cgroup.memory=nobpf kernel parameter option to disable BPF memory accounting for container environments. Netfilter: - Remove the CLUSTERIP target. It has been marked as obsolete for years, and we still have WARN splats wrt races of the out-of-band /proc interface installed by this target. - Add 'destroy' commands to nf_tables. They are identical to the existing 'delete' commands, but do not return an error if the referenced object (set, chain, rule...) did not exist. Driver API: - Improve cpumask_local_spread() locality to help NICs set the right IRQ affinity on AMD platforms. - Separate C22 and C45 MDIO bus transactions more clearly. - Introduce new DCB table to control DSCP rewrite on egress. - Support configuration of Physical Layer Collision Avoidance (PLCA) Reconciliation Sublayer (RS) (802.3cg-2019). Modern version of shared medium Ethernet. - Support for MAC Merge layer (IEEE 802.3-2018 clause 99). Allowing preemption of low priority frames by high priority frames. - Add support for controlling MACSec offload using netlink SET. - Rework devlink instance refcounts to allow registration and de-registration under the instance lock. Split the code into multiple files, drop some of the unnecessarily granular locks and factor out common parts of netlink operation handling. - Add TX frame aggregation parameters (for USB drivers). - Add a new attr TCA_EXT_WARN_MSG to report TC (offload) warning messages with notifications for debug. - Allow offloading of UDP NEW connections via act_ct. - Add support for per action HW stats in TC. - Support hardware miss to TC action (continue processing in SW from a specific point in the action chain). - Warn if old Wireless Extension user space interface is used with modern cfg80211/mac80211 drivers. Do not support Wireless Extensions for Wi-Fi 7 devices at all. Everyone should switch to using nl80211 interface instead. - Improve the CAN bit timing configuration. Use extack to return error messages directly to user space, update the SJW handling, including the definition of a new default value that will benefit CAN-FD controllers, by increasing their oscillator tolerance. New hardware / drivers: - Ethernet: - nVidia BlueField-3 support (control traffic driver) - Ethernet support for imx93 SoCs - Motorcomm yt8531 gigabit Ethernet PHY - onsemi NCN26000 10BASE-T1S PHY (with support for PLCA) - Microchip LAN8841 PHY (incl. cable diagnostics and PTP) - Amlogic gxl MDIO mux - WiFi: - RealTek RTL8188EU (rtl8xxxu) - Qualcomm Wi-Fi 7 devices (ath12k) - CAN: - Renesas R-Car V4H Drivers: - Bluetooth: - Set Per Platform Antenna Gain (PPAG) for Intel controllers. - Ethernet NICs: - Intel (1G, igc): - support TSN / Qbv / packet scheduling features of i226 model - Intel (100G, ice): - use GNSS subsystem instead of TTY - multi-buffer XDP support - extend support for GPIO pins to E823 devices - nVidia/Mellanox: - update the shared buffer configuration on PFC commands - implement PTP adjphase function for HW offset control - TC support for Geneve and GRE with VF tunnel offload - more efficient crypto key management method - multi-port eswitch support - Netronome/Corigine: - add DCB IEEE support - support IPsec offloading for NFP3800 - Freescale/NXP (enetc): - support XDP_REDIRECT for XDP non-linear buffers - improve reconfig, avoid link flap and waiting for idle - support MAC Merge layer - Other NICs: - sfc/ef100: add basic devlink support for ef100 - ionic: rx_push mode operation (writing descriptors via MMIO) - bnxt: use the auxiliary bus abstraction for RDMA - r8169: disable ASPM and reset bus in case of tx timeout - cpsw: support QSGMII mode for J721e CPSW9G - cpts: support pulse-per-second output - ngbe: add an mdio bus driver - usbnet: optimize usbnet_bh() by avoiding unnecessary queuing - r8152: handle devices with FW with NCM support - amd-xgbe: support 10Mbps, 2.5GbE speeds and rx-adaptation - virtio-net: support multi buffer XDP - virtio/vsock: replace virtio_vsock_pkt with sk_buff - tsnep: XDP support - Ethernet high-speed switches: - nVidia/Mellanox (mlxsw): - add support for latency TLV (in FW control messages) - Microchip (sparx5): - separate explicit and implicit traffic forwarding rules, make the implicit rules always active - add support for egress DSCP rewrite - IS0 VCAP support (Ingress Classification) - IS2 VCAP filters (protos, L3 addrs, L4 ports, flags, ToS etc.) - ES2 VCAP support (Egress Access Control) - support for Per-Stream Filtering and Policing (802.1Q, 8.6.5.1) - Ethernet embedded switches: - Marvell (mv88e6xxx): - add MAB (port auth) offload support - enable PTP receive for mv88e6390 - NXP (ocelot): - support MAC Merge layer - support for the the vsc7512 internal copper phys - Microchip: - lan9303: convert to PHYLINK - lan966x: support TC flower filter statistics - lan937x: PTP support for KSZ9563/KSZ8563 and LAN937x - lan937x: support Credit Based Shaper configuration - ksz9477: support Energy Efficient Ethernet - other: - qca8k: convert to regmap read/write API, use bulk operations - rswitch: Improve TX timestamp accuracy - Intel WiFi (iwlwifi): - EHT (Wi-Fi 7) rate reporting - STEP equalizer support: transfer some STEP (connection to radio on platforms with integrated wifi) related parameters from the BIOS to the firmware. - Qualcomm 802.11ax WiFi (ath11k): - IPQ5018 support - Fine Timing Measurement (FTM) responder role support - channel 177 support - MediaTek WiFi (mt76): - per-PHY LED support - mt7996: EHT (Wi-Fi 7) support - Wireless Ethernet Dispatch (WED) reset support - switch to using page pool allocator - RealTek WiFi (rtw89): - support new version of Bluetooth co-existance - Mobile: - rmnet: support TX aggregation" * tag 'net-next-6.3' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next: (1872 commits) page_pool: add a comment explaining the fragment counter usage net: ethtool: fix __ethtool_dev_mm_supported() implementation ethtool: pse-pd: Fix double word in comments xsk: add linux/vmalloc.h to xsk.c sefltests: netdevsim: wait for devlink instance after netns removal selftest: fib_tests: Always cleanup before exit net/mlx5e: Align IPsec ASO result memory to be as required by hardware net/mlx5e: TC, Set CT miss to the specific ct action instance net/mlx5e: Rename CHAIN_TO_REG to MAPPED_OBJ_TO_REG net/mlx5: Refactor tc miss handling to a single function net/mlx5: Kconfig: Make tc offload depend on tc skb extension net/sched: flower: Support hardware miss to tc action net/sched: flower: Move filter handle initialization earlier net/sched: cls_api: Support hardware miss to tc action net/sched: Rename user cookie and act cookie sfc: fix builds without CONFIG_RTC_LIB sfc: clean up some inconsistent indentings net/mlx4_en: Introduce flexible array to silence overflow warning net: lan966x: Fix possible deadlock inside PTP net/ulp: Remove redundant ->clone() test in inet_clone_ulp(). ...
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+===========================================
+CPU topology binding description
+===========================================
+
+===========================================
+1 - Introduction
+===========================================
+
+In a SMP system, the hierarchy of CPUs is defined through three entities that
+are used to describe the layout of physical CPUs in the system:
+
+- socket
+- cluster
+- core
+- thread
+
+The bottom hierarchy level sits at core or thread level depending on whether
+symmetric multi-threading (SMT) is supported or not.
+
+For instance in a system where CPUs support SMT, "cpu" nodes represent all
+threads existing in the system and map to the hierarchy level "thread" above.
+In systems where SMT is not supported "cpu" nodes represent all cores present
+in the system and map to the hierarchy level "core" above.
+
+CPU topology bindings allow one to associate cpu nodes with hierarchical groups
+corresponding to the system hierarchy; syntactically they are defined as device
+tree nodes.
+
+Currently, only ARM/RISC-V intend to use this cpu topology binding but it may be
+used for any other architecture as well.
+
+The cpu nodes, as per bindings defined in [4], represent the devices that
+correspond to physical CPUs and are to be mapped to the hierarchy levels.
+
+A topology description containing phandles to cpu nodes that are not compliant
+with bindings standardized in [4] is therefore considered invalid.
+
+===========================================
+2 - cpu-map node
+===========================================
+
+The ARM/RISC-V CPU topology is defined within the cpu-map node, which is a direct
+child of the cpus node and provides a container where the actual topology
+nodes are listed.
+
+- cpu-map node
+
+ Usage: Optional - On SMP systems provide CPUs topology to the OS.
+ Uniprocessor systems do not require a topology
+ description and therefore should not define a
+ cpu-map node.
+
+ Description: The cpu-map node is just a container node where its
+ subnodes describe the CPU topology.
+
+ Node name must be "cpu-map".
+
+ The cpu-map node's parent node must be the cpus node.
+
+ The cpu-map node's child nodes can be:
+
+ - one or more cluster nodes or
+ - one or more socket nodes in a multi-socket system
+
+ Any other configuration is considered invalid.
+
+The cpu-map node can only contain 4 types of child nodes:
+
+- socket node
+- cluster node
+- core node
+- thread node
+
+whose bindings are described in paragraph 3.
+
+The nodes describing the CPU topology (socket/cluster/core/thread) can
+only be defined within the cpu-map node and every core/thread in the
+system must be defined within the topology. Any other configuration is
+invalid and therefore must be ignored.
+
+===========================================
+2.1 - cpu-map child nodes naming convention
+===========================================
+
+cpu-map child nodes must follow a naming convention where the node name
+must be "socketN", "clusterN", "coreN", "threadN" depending on the node type
+(ie socket/cluster/core/thread) (where N = {0, 1, ...} is the node number; nodes
+which are siblings within a single common parent node must be given a unique and
+sequential N value, starting from 0).
+cpu-map child nodes which do not share a common parent node can have the same
+name (ie same number N as other cpu-map child nodes at different device tree
+levels) since name uniqueness will be guaranteed by the device tree hierarchy.
+
+===========================================
+3 - socket/cluster/core/thread node bindings
+===========================================
+
+Bindings for socket/cluster/cpu/thread nodes are defined as follows:
+
+- socket node
+
+ Description: must be declared within a cpu-map node, one node
+ per physical socket in the system. A system can
+ contain single or multiple physical socket.
+ The association of sockets and NUMA nodes is beyond
+ the scope of this bindings, please refer [2] for
+ NUMA bindings.
+
+ This node is optional for a single socket system.
+
+ The socket node name must be "socketN" as described in 2.1 above.
+ A socket node can not be a leaf node.
+
+ A socket node's child nodes must be one or more cluster nodes.
+
+ Any other configuration is considered invalid.
+
+- cluster node
+
+ Description: must be declared within a cpu-map node, one node
+ per cluster. A system can contain several layers of
+ clustering within a single physical socket and cluster
+ nodes can be contained in parent cluster nodes.
+
+ The cluster node name must be "clusterN" as described in 2.1 above.
+ A cluster node can not be a leaf node.
+
+ A cluster node's child nodes must be:
+
+ - one or more cluster nodes; or
+ - one or more core nodes
+
+ Any other configuration is considered invalid.
+
+- core node
+
+ Description: must be declared in a cluster node, one node per core in
+ the cluster. If the system does not support SMT, core
+ nodes are leaf nodes, otherwise they become containers of
+ thread nodes.
+
+ The core node name must be "coreN" as described in 2.1 above.
+
+ A core node must be a leaf node if SMT is not supported.
+
+ Properties for core nodes that are leaf nodes:
+
+ - cpu
+ Usage: required
+ Value type: <phandle>
+ Definition: a phandle to the cpu node that corresponds to the
+ core node.
+
+ If a core node is not a leaf node (CPUs supporting SMT) a core node's
+ child nodes can be:
+
+ - one or more thread nodes
+
+ Any other configuration is considered invalid.
+
+- thread node
+
+ Description: must be declared in a core node, one node per thread
+ in the core if the system supports SMT. Thread nodes are
+ always leaf nodes in the device tree.
+
+ The thread node name must be "threadN" as described in 2.1 above.
+
+ A thread node must be a leaf node.
+
+ A thread node must contain the following property:
+
+ - cpu
+ Usage: required
+ Value type: <phandle>
+ Definition: a phandle to the cpu node that corresponds to
+ the thread node.
+
+===========================================
+4 - Example dts
+===========================================
+
+Example 1 (ARM 64-bit, 16-cpu system, two clusters of clusters in a single
+physical socket):
+
+cpus {
+ #size-cells = <0>;
+ #address-cells = <2>;
+
+ cpu-map {
+ socket0 {
+ cluster0 {
+ cluster0 {
+ core0 {
+ thread0 {
+ cpu = <&CPU0>;
+ };
+ thread1 {
+ cpu = <&CPU1>;
+ };
+ };
+
+ core1 {
+ thread0 {
+ cpu = <&CPU2>;
+ };
+ thread1 {
+ cpu = <&CPU3>;
+ };
+ };
+ };
+
+ cluster1 {
+ core0 {
+ thread0 {
+ cpu = <&CPU4>;
+ };
+ thread1 {
+ cpu = <&CPU5>;
+ };
+ };
+
+ core1 {
+ thread0 {
+ cpu = <&CPU6>;
+ };
+ thread1 {
+ cpu = <&CPU7>;
+ };
+ };
+ };
+ };
+
+ cluster1 {
+ cluster0 {
+ core0 {
+ thread0 {
+ cpu = <&CPU8>;
+ };
+ thread1 {
+ cpu = <&CPU9>;
+ };
+ };
+ core1 {
+ thread0 {
+ cpu = <&CPU10>;
+ };
+ thread1 {
+ cpu = <&CPU11>;
+ };
+ };
+ };
+
+ cluster1 {
+ core0 {
+ thread0 {
+ cpu = <&CPU12>;
+ };
+ thread1 {
+ cpu = <&CPU13>;
+ };
+ };
+ core1 {
+ thread0 {
+ cpu = <&CPU14>;
+ };
+ thread1 {
+ cpu = <&CPU15>;
+ };
+ };
+ };
+ };
+ };
+ };
+
+ CPU0: cpu@0 {
+ device_type = "cpu";
+ compatible = "arm,cortex-a57";
+ reg = <0x0 0x0>;
+ enable-method = "spin-table";
+ cpu-release-addr = <0 0x20000000>;
+ };
+
+ CPU1: cpu@1 {
+ device_type = "cpu";
+ compatible = "arm,cortex-a57";
+ reg = <0x0 0x1>;
+ enable-method = "spin-table";
+ cpu-release-addr = <0 0x20000000>;
+ };
+
+ CPU2: cpu@100 {
+ device_type = "cpu";
+ compatible = "arm,cortex-a57";
+ reg = <0x0 0x100>;
+ enable-method = "spin-table";
+ cpu-release-addr = <0 0x20000000>;
+ };
+
+ CPU3: cpu@101 {
+ device_type = "cpu";
+ compatible = "arm,cortex-a57";
+ reg = <0x0 0x101>;
+ enable-method = "spin-table";
+ cpu-release-addr = <0 0x20000000>;
+ };
+
+ CPU4: cpu@10000 {
+ device_type = "cpu";
+ compatible = "arm,cortex-a57";
+ reg = <0x0 0x10000>;
+ enable-method = "spin-table";
+ cpu-release-addr = <0 0x20000000>;
+ };
+
+ CPU5: cpu@10001 {
+ device_type = "cpu";
+ compatible = "arm,cortex-a57";
+ reg = <0x0 0x10001>;
+ enable-method = "spin-table";
+ cpu-release-addr = <0 0x20000000>;
+ };
+
+ CPU6: cpu@10100 {
+ device_type = "cpu";
+ compatible = "arm,cortex-a57";
+ reg = <0x0 0x10100>;
+ enable-method = "spin-table";
+ cpu-release-addr = <0 0x20000000>;
+ };
+
+ CPU7: cpu@10101 {
+ device_type = "cpu";
+ compatible = "arm,cortex-a57";
+ reg = <0x0 0x10101>;
+ enable-method = "spin-table";
+ cpu-release-addr = <0 0x20000000>;
+ };
+
+ CPU8: cpu@100000000 {
+ device_type = "cpu";
+ compatible = "arm,cortex-a57";
+ reg = <0x1 0x0>;
+ enable-method = "spin-table";
+ cpu-release-addr = <0 0x20000000>;
+ };
+
+ CPU9: cpu@100000001 {
+ device_type = "cpu";
+ compatible = "arm,cortex-a57";
+ reg = <0x1 0x1>;
+ enable-method = "spin-table";
+ cpu-release-addr = <0 0x20000000>;
+ };
+
+ CPU10: cpu@100000100 {
+ device_type = "cpu";
+ compatible = "arm,cortex-a57";
+ reg = <0x1 0x100>;
+ enable-method = "spin-table";
+ cpu-release-addr = <0 0x20000000>;
+ };
+
+ CPU11: cpu@100000101 {
+ device_type = "cpu";
+ compatible = "arm,cortex-a57";
+ reg = <0x1 0x101>;
+ enable-method = "spin-table";
+ cpu-release-addr = <0 0x20000000>;
+ };
+
+ CPU12: cpu@100010000 {
+ device_type = "cpu";
+ compatible = "arm,cortex-a57";
+ reg = <0x1 0x10000>;
+ enable-method = "spin-table";
+ cpu-release-addr = <0 0x20000000>;
+ };
+
+ CPU13: cpu@100010001 {
+ device_type = "cpu";
+ compatible = "arm,cortex-a57";
+ reg = <0x1 0x10001>;
+ enable-method = "spin-table";
+ cpu-release-addr = <0 0x20000000>;
+ };
+
+ CPU14: cpu@100010100 {
+ device_type = "cpu";
+ compatible = "arm,cortex-a57";
+ reg = <0x1 0x10100>;
+ enable-method = "spin-table";
+ cpu-release-addr = <0 0x20000000>;
+ };
+
+ CPU15: cpu@100010101 {
+ device_type = "cpu";
+ compatible = "arm,cortex-a57";
+ reg = <0x1 0x10101>;
+ enable-method = "spin-table";
+ cpu-release-addr = <0 0x20000000>;
+ };
+};
+
+Example 2 (ARM 32-bit, dual-cluster, 8-cpu system, no SMT):
+
+cpus {
+ #size-cells = <0>;
+ #address-cells = <1>;
+
+ cpu-map {
+ cluster0 {
+ core0 {
+ cpu = <&CPU0>;
+ };
+ core1 {
+ cpu = <&CPU1>;
+ };
+ core2 {
+ cpu = <&CPU2>;
+ };
+ core3 {
+ cpu = <&CPU3>;
+ };
+ };
+
+ cluster1 {
+ core0 {
+ cpu = <&CPU4>;
+ };
+ core1 {
+ cpu = <&CPU5>;
+ };
+ core2 {
+ cpu = <&CPU6>;
+ };
+ core3 {
+ cpu = <&CPU7>;
+ };
+ };
+ };
+
+ CPU0: cpu@0 {
+ device_type = "cpu";
+ compatible = "arm,cortex-a15";
+ reg = <0x0>;
+ };
+
+ CPU1: cpu@1 {
+ device_type = "cpu";
+ compatible = "arm,cortex-a15";
+ reg = <0x1>;
+ };
+
+ CPU2: cpu@2 {
+ device_type = "cpu";
+ compatible = "arm,cortex-a15";
+ reg = <0x2>;
+ };
+
+ CPU3: cpu@3 {
+ device_type = "cpu";
+ compatible = "arm,cortex-a15";
+ reg = <0x3>;
+ };
+
+ CPU4: cpu@100 {
+ device_type = "cpu";
+ compatible = "arm,cortex-a7";
+ reg = <0x100>;
+ };
+
+ CPU5: cpu@101 {
+ device_type = "cpu";
+ compatible = "arm,cortex-a7";
+ reg = <0x101>;
+ };
+
+ CPU6: cpu@102 {
+ device_type = "cpu";
+ compatible = "arm,cortex-a7";
+ reg = <0x102>;
+ };
+
+ CPU7: cpu@103 {
+ device_type = "cpu";
+ compatible = "arm,cortex-a7";
+ reg = <0x103>;
+ };
+};
+
+Example 3: HiFive Unleashed (RISC-V 64 bit, 4 core system)
+
+{
+ #address-cells = <2>;
+ #size-cells = <2>;
+ compatible = "sifive,fu540g", "sifive,fu500";
+ model = "sifive,hifive-unleashed-a00";
+
+ ...
+ cpus {
+ #address-cells = <1>;
+ #size-cells = <0>;
+ cpu-map {
+ socket0 {
+ cluster0 {
+ core0 {
+ cpu = <&CPU1>;
+ };
+ core1 {
+ cpu = <&CPU2>;
+ };
+ core2 {
+ cpu0 = <&CPU2>;
+ };
+ core3 {
+ cpu0 = <&CPU3>;
+ };
+ };
+ };
+ };
+
+ CPU1: cpu@1 {
+ device_type = "cpu";
+ compatible = "sifive,rocket0", "riscv";
+ reg = <0x1>;
+ }
+
+ CPU2: cpu@2 {
+ device_type = "cpu";
+ compatible = "sifive,rocket0", "riscv";
+ reg = <0x2>;
+ }
+ CPU3: cpu@3 {
+ device_type = "cpu";
+ compatible = "sifive,rocket0", "riscv";
+ reg = <0x3>;
+ }
+ CPU4: cpu@4 {
+ device_type = "cpu";
+ compatible = "sifive,rocket0", "riscv";
+ reg = <0x4>;
+ }
+ }
+};
+===============================================================================
+[1] ARM Linux kernel documentation
+ Documentation/devicetree/bindings/arm/cpus.yaml
+[2] Devicetree NUMA binding description
+ Documentation/devicetree/bindings/numa.txt
+[3] RISC-V Linux kernel documentation
+ Documentation/devicetree/bindings/riscv/cpus.yaml
+[4] https://www.devicetree.org/specifications/