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+# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/rtc/apple,smc-rtc.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: Apple SMC RTC
+
+description:
+ Apple Silicon Macs (M1, etc.) have an RTC that is part of the PMU IC,
+ but most of the PMU functionality is abstracted out by the SMC.
+ An additional RTC offset stored inside NVMEM is required to compute
+ the current date/time.
+
+maintainers:
+ - Sven Peter <sven@kernel.org>
+
+properties:
+ compatible:
+ const: apple,smc-rtc
+
+ nvmem-cells:
+ items:
+ - description: 48bit RTC offset, specified in 32768 (2^15) Hz clock ticks
+
+ nvmem-cell-names:
+ items:
+ - const: rtc_offset
+
+required:
+ - compatible
+ - nvmem-cells
+ - nvmem-cell-names
+
+additionalProperties: false