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
182 - nvidia,tegra132-denver
183 - nvidia,tegra186-denver
184 - nvidia,tegra194-carmel
205 $ref: /schemas/types.yaml#/definitions/string
207 # On ARM v8 64-bit this property is required
211 # On ARM 32-bit systems this property is optional
214 - allwinner,sun6i-a31
215 - allwinner,sun8i-a23
216 - allwinner,sun9i-a80-smp
217 - allwinner,sun8i-a83t-smp
219 - amlogic,meson8b-smp
222 - brcm,bcm11351-cpu-method
228 - marvell,armada-375-smp
229 - marvell,armada-380-smp
230 - marvell,armada-390-smp
231 - marvell,armada-xp-smp
232 - marvell,98dx3236-smp
234 - mediatek,mt6589-smp
235 - mediatek,mt81xx-tz-smp
241 # Only valid on ARM 32-bit, see above for ARM v8 64-bit
244 - renesas,r9a06g032-smp
245 - rockchip,rk3036-smp
246 - rockchip,rk3066-smp
247 - socionext,milbeaut-m10v-smp
254 - $ref: /schemas/types.yaml#/definitions/uint32
255 - $ref: /schemas/types.yaml#/definitions/uint64
257 The DT specification defines this as 64-bit always, but some 32-bit Arm
258 systems have used a 32-bit value which must be supported.
259 Required for systems that have an "enable-method"
260 property value of "spin-table".
263 $ref: /schemas/types.yaml#/definitions/phandle-array
267 List of phandles to idle state nodes supported
268 by this cpu (see ./idle-states.yaml).
272 u32 value representing CPU capacity (see ../cpu/cpu-capacity.txt) in
273 DMIPS/MHz, relative to highest capacity-dmips-mhz
276 cci-control-port: true
278 dynamic-power-coefficient:
279 $ref: /schemas/types.yaml#/definitions/uint32
281 A u32 value that represents the running time dynamic
282 power coefficient in units of uW/MHz/V^2. The
283 coefficient can either be calculated from power
284 measurements or derived by analysis.
286 The dynamic power consumption of the CPU is
287 proportional to the square of the Voltage (V) and
288 the clock frequency (f). The coefficient is used to
289 calculate the dynamic power as below -
291 Pdyn = dynamic-power-coefficient * V^2 * f
293 where voltage is in V, frequency is in MHz.
298 List of phandles and performance domain specifiers, as defined by
299 bindings of the performance domain provider. See also
300 dvfs/performance-domain.yaml.
304 List of phandles and PM domain specifiers, as defined by bindings of the
305 PM domain provider (see also ../power_domain.txt).
309 A list of power domain name strings sorted in the same order as the
310 power-domains property.
312 For PSCI based platforms, the name corresponding to the index of the PSCI
313 PM domain provider, must be "psci". For SCMI based platforms, the name
314 corresponding to the index of an SCMI performance domain provider, must be
318 $ref: /schemas/types.yaml#/definitions/phandle
320 Specifies the SAW* node associated with this CPU.
322 Required for systems that have an "enable-method" property
323 value of "qcom,kpss-acc-v1" or "qcom,kpss-acc-v2"
325 * arm/msm/qcom,saw2.txt
328 $ref: /schemas/types.yaml#/definitions/phandle
330 Specifies the ACC* node associated with this CPU.
332 Required for systems that have an "enable-method" property
333 value of "qcom,kpss-acc-v1", "qcom,kpss-acc-v2", "qcom,msm8226-smp" or
336 * arm/msm/qcom,kpss-acc.txt
339 $ref: /schemas/types.yaml#/definitions/phandle
341 Specifies the syscon node controlling the cpu core power domains.
343 Optional for systems that have an "enable-method"
344 property value of "rockchip,rk3066-smp"
345 While optional, it is the preferred way to get access to
346 the cpu-core power-domains.
349 $ref: /schemas/types.yaml#/definitions/uint32
351 Required for systems that have an "enable-method" property value of
352 "brcm,bcm11351-cpu-method", "brcm,bcm23550" or "brcm,bcm-nsp-smp".
354 This includes the following SoCs: |
355 BCM11130, BCM11140, BCM11351, BCM28145, BCM28155, BCM21664, BCM23550
356 BCM58522, BCM58525, BCM58535, BCM58622, BCM58623, BCM58625, BCM88312
358 The secondary-boot-reg property is a u32 value that specifies the
359 physical address of the register used to request the ROM holding pen
360 code release a secondary CPU. The value written to the register is
361 formed by encoding the target CPU id into the low bits of the
362 physical start address it should jump to.
365 # If the enable-method property contains one of those values
370 - brcm,bcm11351-cpu-method
373 # and if enable-method is present
387 rockchip,pmu: [enable-method]
389 additionalProperties: true
395 #address-cells = <1>;
399 compatible = "arm,cortex-a15";
405 compatible = "arm,cortex-a15";
411 compatible = "arm,cortex-a7";
417 compatible = "arm,cortex-a7";
423 // Example 2 (Cortex-A8 uniprocessor 32-bit system):
426 #address-cells = <1>;
430 compatible = "arm,cortex-a8";
436 // Example 3 (ARM 926EJ-S uniprocessor 32-bit system):
439 #address-cells = <1>;
443 compatible = "arm,arm926ej-s";
449 // Example 4 (ARM Cortex-A57 64-bit system):
452 #address-cells = <2>;
456 compatible = "arm,cortex-a57";
458 enable-method = "spin-table";
459 cpu-release-addr = <0 0x20000000>;
464 compatible = "arm,cortex-a57";
466 enable-method = "spin-table";
467 cpu-release-addr = <0 0x20000000>;
472 compatible = "arm,cortex-a57";
474 enable-method = "spin-table";
475 cpu-release-addr = <0 0x20000000>;
480 compatible = "arm,cortex-a57";
482 enable-method = "spin-table";
483 cpu-release-addr = <0 0x20000000>;
488 compatible = "arm,cortex-a57";
490 enable-method = "spin-table";
491 cpu-release-addr = <0 0x20000000>;
496 compatible = "arm,cortex-a57";
498 enable-method = "spin-table";
499 cpu-release-addr = <0 0x20000000>;
504 compatible = "arm,cortex-a57";
506 enable-method = "spin-table";
507 cpu-release-addr = <0 0x20000000>;
512 compatible = "arm,cortex-a57";
514 enable-method = "spin-table";
515 cpu-release-addr = <0 0x20000000>;
520 compatible = "arm,cortex-a57";
522 enable-method = "spin-table";
523 cpu-release-addr = <0 0x20000000>;
528 compatible = "arm,cortex-a57";
530 enable-method = "spin-table";
531 cpu-release-addr = <0 0x20000000>;
536 compatible = "arm,cortex-a57";
538 enable-method = "spin-table";
539 cpu-release-addr = <0 0x20000000>;
544 compatible = "arm,cortex-a57";
546 enable-method = "spin-table";
547 cpu-release-addr = <0 0x20000000>;
552 compatible = "arm,cortex-a57";
554 enable-method = "spin-table";
555 cpu-release-addr = <0 0x20000000>;
560 compatible = "arm,cortex-a57";
562 enable-method = "spin-table";
563 cpu-release-addr = <0 0x20000000>;
568 compatible = "arm,cortex-a57";
570 enable-method = "spin-table";
571 cpu-release-addr = <0 0x20000000>;
576 compatible = "arm,cortex-a57";
578 enable-method = "spin-table";
579 cpu-release-addr = <0 0x20000000>;