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.
122 - arm,armv8 # Only for s/w models
188 - nvidia,tegra132-denver
189 - nvidia,tegra186-denver
190 - nvidia,tegra194-carmel
211 $ref: /schemas/types.yaml#/definitions/string
213 # On ARM v8 64-bit this property is required
217 # On ARM 32-bit systems this property is optional
220 - allwinner,sun6i-a31
221 - allwinner,sun8i-a23
222 - allwinner,sun9i-a80-smp
223 - allwinner,sun8i-a83t-smp
225 - amlogic,meson8b-smp
228 - brcm,bcm11351-cpu-method
234 - marvell,armada-375-smp
235 - marvell,armada-380-smp
236 - marvell,armada-390-smp
237 - marvell,armada-xp-smp
238 - marvell,98dx3236-smp
240 - mediatek,mt6589-smp
241 - mediatek,mt81xx-tz-smp
247 # Only valid on ARM 32-bit, see above for ARM v8 64-bit
250 - renesas,r9a06g032-smp
251 - rockchip,rk3036-smp
252 - rockchip,rk3066-smp
253 - socionext,milbeaut-m10v-smp
260 - $ref: /schemas/types.yaml#/definitions/uint32
261 - $ref: /schemas/types.yaml#/definitions/uint64
263 The DT specification defines this as 64-bit always, but some 32-bit Arm
264 systems have used a 32-bit value which must be supported.
265 Required for systems that have an "enable-method"
266 property value of "spin-table".
269 $ref: /schemas/types.yaml#/definitions/phandle-array
273 List of phandles to idle state nodes supported
274 by this cpu (see ./idle-states.yaml).
278 u32 value representing CPU capacity (see ../cpu/cpu-capacity.txt) in
279 DMIPS/MHz, relative to highest capacity-dmips-mhz
282 cci-control-port: true
284 dynamic-power-coefficient:
285 $ref: /schemas/types.yaml#/definitions/uint32
287 A u32 value that represents the running time dynamic
288 power coefficient in units of uW/MHz/V^2. The
289 coefficient can either be calculated from power
290 measurements or derived by analysis.
292 The dynamic power consumption of the CPU is
293 proportional to the square of the Voltage (V) and
294 the clock frequency (f). The coefficient is used to
295 calculate the dynamic power as below -
297 Pdyn = dynamic-power-coefficient * V^2 * f
299 where voltage is in V, frequency is in MHz.
304 List of phandles and performance domain specifiers, as defined by
305 bindings of the performance domain provider. See also
306 dvfs/performance-domain.yaml.
310 List of phandles and PM domain specifiers, as defined by bindings of the
311 PM domain provider (see also ../power_domain.txt).
315 A list of power domain name strings sorted in the same order as the
316 power-domains property.
318 For PSCI based platforms, the name corresponding to the index of the PSCI
319 PM domain provider, must be "psci". For SCMI based platforms, the name
320 corresponding to the index of an SCMI performance domain provider, must be
324 $ref: /schemas/types.yaml#/definitions/phandle
326 Specifies the SAW* node associated with this CPU.
328 Required for systems that have an "enable-method" property
329 value of "qcom,kpss-acc-v1" or "qcom,kpss-acc-v2"
331 * arm/msm/qcom,saw2.txt
334 $ref: /schemas/types.yaml#/definitions/phandle
336 Specifies the ACC* node associated with this CPU.
338 Required for systems that have an "enable-method" property
339 value of "qcom,kpss-acc-v1", "qcom,kpss-acc-v2", "qcom,msm8226-smp" or
342 * arm/msm/qcom,kpss-acc.txt
345 $ref: /schemas/types.yaml#/definitions/phandle
347 Specifies the syscon node controlling the cpu core power domains.
349 Optional for systems that have an "enable-method"
350 property value of "rockchip,rk3066-smp"
351 While optional, it is the preferred way to get access to
352 the cpu-core power-domains.
355 $ref: /schemas/types.yaml#/definitions/uint32
357 Required for systems that have an "enable-method" property value of
358 "brcm,bcm11351-cpu-method", "brcm,bcm23550" or "brcm,bcm-nsp-smp".
360 This includes the following SoCs: |
361 BCM11130, BCM11140, BCM11351, BCM28145, BCM28155, BCM21664, BCM23550
362 BCM58522, BCM58525, BCM58535, BCM58622, BCM58623, BCM58625, BCM88312
364 The secondary-boot-reg property is a u32 value that specifies the
365 physical address of the register used to request the ROM holding pen
366 code release a secondary CPU. The value written to the register is
367 formed by encoding the target CPU id into the low bits of the
368 physical start address it should jump to.
371 # If the enable-method property contains one of those values
376 - brcm,bcm11351-cpu-method
379 # and if enable-method is present
393 rockchip,pmu: [enable-method]
395 additionalProperties: true
401 #address-cells = <1>;
405 compatible = "arm,cortex-a15";
411 compatible = "arm,cortex-a15";
417 compatible = "arm,cortex-a7";
423 compatible = "arm,cortex-a7";
429 // Example 2 (Cortex-A8 uniprocessor 32-bit system):
432 #address-cells = <1>;
436 compatible = "arm,cortex-a8";
442 // Example 3 (ARM 926EJ-S uniprocessor 32-bit system):
445 #address-cells = <1>;
449 compatible = "arm,arm926ej-s";
455 // Example 4 (ARM Cortex-A57 64-bit system):
458 #address-cells = <2>;
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>;
574 compatible = "arm,cortex-a57";
576 enable-method = "spin-table";
577 cpu-release-addr = <0 0x20000000>;
582 compatible = "arm,cortex-a57";
584 enable-method = "spin-table";
585 cpu-release-addr = <0 0x20000000>;