linux/Documentation/devicetree/bindings/tpm/tcg,tpm-tis-mmio.yaml
Lukas Wunner 26c9d152eb dt-bindings: tpm: Consolidate TCG TIS bindings
A significant number of Trusted Platform Modules conform to the "TIS"
specification published by the Trusted Computing Group ("TCG PC Client
Specific TPM Interface Specification").  These chips typically use an
SPI, I²C or LPC bus as transport (via MMIO in the latter case).  Some
of them even support multiple of those buses (selectable through a
config strap) or the same chip is available in multiple SKUs, each with
a different bus interface.

The devicetree bindings for these TPMs have not been converted to DT
schema yet and are spread out across 3 generic files and 2 chip-specific
files.  A few TPM compatible strings were added to trivial-devices.yaml
even though additional properties are documented in the plaintext
bindings.

Consolidate the devicetree bindings into 3 yaml files, one per bus.

Move common properties to a separate tpm-common.yaml.

Document compatible strings which are supported by the TPM TIS driver
but were neglected to be added to the devicetree bindings.

Document the memory-region property recently introduced by commit
1e2714bb83fc ("tpm: Add reserved memory event log").

Signed-off-by: Lukas Wunner <lukas@wunner.de>
Reviewed-by: Rob Herring <robh@kernel.org>
Link: https://lore.kernel.org/r/953fd4c7519030db88e5b5e12ab6307414ebdd21.1702806810.git.lukas@wunner.de
Signed-off-by: Rob Herring <robh@kernel.org>
2024-01-09 10:56:18 -06:00

50 lines
1.3 KiB
YAML

# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
%YAML 1.2
---
$id: http://devicetree.org/schemas/tpm/tcg,tpm-tis-mmio.yaml#
$schema: http://devicetree.org/meta-schemas/core.yaml#
title: MMIO-accessed Trusted Platform Module conforming to TCG TIS specification
maintainers:
- Lukas Wunner <lukas@wunner.de>
description: |
The Trusted Computing Group (TCG) has defined a multi-vendor standard
for accessing a TPM chip. It can be transported over various buses,
one of them being LPC (via MMIO). The standard is named:
TCG PC Client Specific TPM Interface Specification (TIS)
https://trustedcomputinggroup.org/resource/pc-client-work-group-pc-client-specific-tpm-interface-specification-tis/
properties:
compatible:
items:
- enum:
- at97sc3201
- atmel,at97sc3204
- socionext,synquacer-tpm-mmio
- const: tcg,tpm-tis-mmio
reg:
description:
location and length of the MMIO registers, length should be
at least 0x5000 bytes
allOf:
- $ref: tpm-common.yaml#
required:
- compatible
- reg
unevaluatedProperties: false
examples:
- |
tpm@90000 {
compatible = "atmel,at97sc3204", "tcg,tpm-tis-mmio";
reg = <0x90000 0x5000>;
interrupt-parent = <&EIC0>;
interrupts = <1 2>;
};