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+# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/tpm/google,cr50.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: Google Security Chip H1 (running Cr50 firmware)
+
+maintainers:
+ - Andrey Pronin <apronin@chromium.org>
+
+description: |
+ Google has designed a family of security chips called "Titan".
+ One member is the H1 built into Chromebooks and running Cr50 firmware:
+ https://www.osfc.io/2018/talks/google-secure-microcontroller-and-ccd-closed-case-debugging/
+
+ The chip provides several functions, including TPM 2.0 like functionality.
+ It communicates over SPI or I²C using the FIFO protocol described in the
+ TCG PC Client Platform TPM Profile Specification for TPM 2.0 (PTP), sec 6:
+ https://trustedcomputinggroup.org/resource/pc-client-platform-tpm-profile-ptp-specification/
+
+properties:
+ compatible:
+ const: google,cr50
+
+allOf:
+ - $ref: tpm-common.yaml#
+
+anyOf:
+ - $ref: /schemas/spi/spi-peripheral-props.yaml#
+ - $ref: tcg,tpm-tis-i2c.yaml#/properties/reg
+
+required:
+ - compatible
+ - reg
+
+unevaluatedProperties: false
+
+examples:
+ - |
+ spi {
+ #address-cells = <1>;
+ #size-cells = <0>;
+
+ tpm@0 {
+ reg = <0>;
+ compatible = "google,cr50";
+ spi-max-frequency = <800000>;
+ };
+ };
+
+ - |
+ #include <dt-bindings/interrupt-controller/irq.h>
+ i2c {
+ #address-cells = <1>;
+ #size-cells = <0>;
+
+ tpm@50 {
+ compatible = "google,cr50";
+ reg = <0x50>;
+ interrupts-extended = <&pio 88 IRQ_TYPE_EDGE_FALLING>;
+ pinctrl-names = "default";
+ pinctrl-0 = <&cr50_int>;
+ };
+ };