1 # SPDX-License-Identifier: GPL-2.0
4 $id: http://devicetree.org/schemas/arm/cpus.yaml#
5 $schema: http://devicetree.org/meta-schemas/core.yaml#
10 - Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
13 The device tree allows to describe the layout of CPUs in a system through
14 the "cpus" node, which in turn contains a number of subnodes (ie "cpu")
15 defining properties for every cpu.
17 Bindings for CPU nodes follow the Devicetree Specification, available from:
19 https://www.devicetree.org/specifications/
21 with updates for 32-bit and 64-bit ARM systems provided in this document.
23 ================================
24 Convention used in this document
25 ================================
27 This document follows the conventions described in the Devicetree
28 Specification, with the addition:
30 - square brackets define bitfields, eg reg[7:0] value of the bitfield in
31 the reg property contained in bits 7 down to 0
33 =====================================
34 cpus and cpu node bindings definition
35 =====================================
37 The ARM architecture, in accordance with the Devicetree Specification,
38 requires the cpus and cpu nodes to be present and contain the properties
45 Usage and definition depend on ARM architecture version and
48 On uniprocessor ARM architectures previous to v7
49 this property is required and must be set to 0.
51 On ARM 11 MPcore based systems this property is
52 required and matches the CPUID[11:0] register bits.
54 Bits [11:0] in the reg cell must be set to
55 bits [11:0] in CPU ID register.
57 All other bits in the reg cell must be set to 0.
59 On 32-bit ARM v7 or later systems this property is
60 required and matches the CPU MPIDR[23:0] register
63 Bits [23:0] in the reg cell must be set to
66 All other bits in the reg cell must be set to 0.
68 On ARM v8 64-bit systems this property is required
69 and matches the MPIDR_EL1 register affinity bits.
71 * If cpus node's #address-cells property is set to 2
73 The first reg cell bits [7:0] must be set to
74 bits [39:32] of MPIDR_EL1.
76 The second reg cell bits [23:0] must be set to
77 bits [23:0] of MPIDR_EL1.
79 * If cpus node's #address-cells property is set to 1
81 The reg cell bits [23:0] must be set to bits [23:0]
84 All other bits in the reg cells must be set to 0.
120 - arm,armv8 # Only for s/w models
176 - nvidia,tegra132-denver
177 - nvidia,tegra186-denver
178 - nvidia,tegra194-carmel
197 $ref: '/schemas/types.yaml#/definitions/string'
199 # On ARM v8 64-bit this property is required
203 # On ARM 32-bit systems this property is optional
206 - allwinner,sun6i-a31
207 - allwinner,sun8i-a23
208 - allwinner,sun9i-a80-smp
209 - allwinner,sun8i-a83t-smp
211 - amlogic,meson8b-smp
214 - brcm,bcm11351-cpu-method
220 - marvell,armada-375-smp
221 - marvell,armada-380-smp
222 - marvell,armada-390-smp
223 - marvell,armada-xp-smp
224 - marvell,98dx3236-smp
226 - mediatek,mt6589-smp
227 - mediatek,mt81xx-tz-smp
233 # Only valid on ARM 32-bit, see above for ARM v8 64-bit
236 - renesas,r9a06g032-smp
237 - rockchip,rk3036-smp
238 - rockchip,rk3066-smp
239 - socionext,milbeaut-m10v-smp
246 - $ref: '/schemas/types.yaml#/definitions/uint32'
247 - $ref: '/schemas/types.yaml#/definitions/uint64'
249 The DT specification defines this as 64-bit always, but some 32-bit Arm
250 systems have used a 32-bit value which must be supported.
251 Required for systems that have an "enable-method"
252 property value of "spin-table".
255 $ref: '/schemas/types.yaml#/definitions/phandle-array'
259 List of phandles to idle state nodes supported
260 by this cpu (see ./idle-states.yaml).
264 u32 value representing CPU capacity (see ../cpu/cpu-capacity.txt) in
265 DMIPS/MHz, relative to highest capacity-dmips-mhz
268 cci-control-port: true
270 dynamic-power-coefficient:
271 $ref: '/schemas/types.yaml#/definitions/uint32'
273 A u32 value that represents the running time dynamic
274 power coefficient in units of uW/MHz/V^2. The
275 coefficient can either be calculated from power
276 measurements or derived by analysis.
278 The dynamic power consumption of the CPU is
279 proportional to the square of the Voltage (V) and
280 the clock frequency (f). The coefficient is used to
281 calculate the dynamic power as below -
283 Pdyn = dynamic-power-coefficient * V^2 * f
285 where voltage is in V, frequency is in MHz.
290 List of phandles and performance domain specifiers, as defined by
291 bindings of the performance domain provider. See also
292 dvfs/performance-domain.yaml.
296 List of phandles and PM domain specifiers, as defined by bindings of the
297 PM domain provider (see also ../power_domain.txt).
301 A list of power domain name strings sorted in the same order as the
302 power-domains property.
304 For PSCI based platforms, the name corresponding to the index of the PSCI
305 PM domain provider, must be "psci".
308 $ref: '/schemas/types.yaml#/definitions/phandle'
310 Specifies the SAW* node associated with this CPU.
312 Required for systems that have an "enable-method" property
313 value of "qcom,kpss-acc-v1" or "qcom,kpss-acc-v2"
315 * arm/msm/qcom,saw2.txt
318 $ref: '/schemas/types.yaml#/definitions/phandle'
320 Specifies the ACC* node associated with this CPU.
322 Required for systems that have an "enable-method" property
323 value of "qcom,kpss-acc-v1", "qcom,kpss-acc-v2", "qcom,msm8226-smp" or
326 * arm/msm/qcom,kpss-acc.txt
329 $ref: '/schemas/types.yaml#/definitions/phandle'
331 Specifies the syscon node controlling the cpu core power domains.
333 Optional for systems that have an "enable-method"
334 property value of "rockchip,rk3066-smp"
335 While optional, it is the preferred way to get access to
336 the cpu-core power-domains.
339 $ref: '/schemas/types.yaml#/definitions/uint32'
341 Required for systems that have an "enable-method" property value of
342 "brcm,bcm11351-cpu-method", "brcm,bcm23550" or "brcm,bcm-nsp-smp".
344 This includes the following SoCs: |
345 BCM11130, BCM11140, BCM11351, BCM28145, BCM28155, BCM21664, BCM23550
346 BCM58522, BCM58525, BCM58535, BCM58622, BCM58623, BCM58625, BCM88312
348 The secondary-boot-reg property is a u32 value that specifies the
349 physical address of the register used to request the ROM holding pen
350 code release a secondary CPU. The value written to the register is
351 formed by encoding the target CPU id into the low bits of the
352 physical start address it should jump to.
355 # If the enable-method property contains one of those values
360 - brcm,bcm11351-cpu-method
363 # and if enable-method is present
377 rockchip,pmu: [enable-method]
379 additionalProperties: true
385 #address-cells = <1>;
389 compatible = "arm,cortex-a15";
395 compatible = "arm,cortex-a15";
401 compatible = "arm,cortex-a7";
407 compatible = "arm,cortex-a7";
413 // Example 2 (Cortex-A8 uniprocessor 32-bit system):
416 #address-cells = <1>;
420 compatible = "arm,cortex-a8";
426 // Example 3 (ARM 926EJ-S uniprocessor 32-bit system):
429 #address-cells = <1>;
433 compatible = "arm,arm926ej-s";
439 // Example 4 (ARM Cortex-A57 64-bit system):
442 #address-cells = <2>;
446 compatible = "arm,cortex-a57";
448 enable-method = "spin-table";
449 cpu-release-addr = <0 0x20000000>;
454 compatible = "arm,cortex-a57";
456 enable-method = "spin-table";
457 cpu-release-addr = <0 0x20000000>;
462 compatible = "arm,cortex-a57";
464 enable-method = "spin-table";
465 cpu-release-addr = <0 0x20000000>;
470 compatible = "arm,cortex-a57";
472 enable-method = "spin-table";
473 cpu-release-addr = <0 0x20000000>;
478 compatible = "arm,cortex-a57";
480 enable-method = "spin-table";
481 cpu-release-addr = <0 0x20000000>;
486 compatible = "arm,cortex-a57";
488 enable-method = "spin-table";
489 cpu-release-addr = <0 0x20000000>;
494 compatible = "arm,cortex-a57";
496 enable-method = "spin-table";
497 cpu-release-addr = <0 0x20000000>;
502 compatible = "arm,cortex-a57";
504 enable-method = "spin-table";
505 cpu-release-addr = <0 0x20000000>;
510 compatible = "arm,cortex-a57";
512 enable-method = "spin-table";
513 cpu-release-addr = <0 0x20000000>;
518 compatible = "arm,cortex-a57";
520 enable-method = "spin-table";
521 cpu-release-addr = <0 0x20000000>;
526 compatible = "arm,cortex-a57";
528 enable-method = "spin-table";
529 cpu-release-addr = <0 0x20000000>;
534 compatible = "arm,cortex-a57";
536 enable-method = "spin-table";
537 cpu-release-addr = <0 0x20000000>;
542 compatible = "arm,cortex-a57";
544 enable-method = "spin-table";
545 cpu-release-addr = <0 0x20000000>;
550 compatible = "arm,cortex-a57";
552 enable-method = "spin-table";
553 cpu-release-addr = <0 0x20000000>;
558 compatible = "arm,cortex-a57";
560 enable-method = "spin-table";
561 cpu-release-addr = <0 0x20000000>;
566 compatible = "arm,cortex-a57";
568 enable-method = "spin-table";
569 cpu-release-addr = <0 0x20000000>;