[PATCH 0/4] Add support for the TPM FF-A start method

Stuart Yoder
2025-02-10T23:22:39Z

These patches add support for the CRB FF-A start method defined
in the TCG ACPI specification v1.4 and the FF-A ABI defined
in the Arm TPM Service CRB over FF-A (DEN0138) specification.
(https://developer.arm.com/documentation/den0138/latest/)

FF-A is a messaging framework for Arm-based systems and in the
context of the TPM driver is used to signal 'start' to a CRB-based
TPM service which is hosted in an FF-A secure partition running in
TrustZone.

The first patch adds an FF-A driver to handle the FF-A messaging when
communicating with a CRB-based TPM secure partition built on FF-A.
The driver is probed when the TPM secure partition is discovered by
the Linux FF-A infrastructure.

The second patch consolidates the check for idle support in the CRB
driver to one place.

The third patch defines the new ACPI start method enumeration for
CRB over FF-A.

The fourth patch adds support for the FF-A ACPI start method to
the TPM crb driver.

Stuart Yoder (4):
tpm_crb: implement driver compliant to CRB over FF-A
tpm_crb: refactor check for idle support into TPM into inline function
ACPICA: add start method for Arm FF-A
tpm_crb: add support for the Arm FF-A start method

drivers/char/tpm/Kconfig | 9 ++
drivers/char/tpm/Makefile | 1 +
drivers/char/tpm/ffa_crb.c | 310 +++++++++++++++++++++++++++++++++++++
drivers/char/tpm/ffa_crb.h | 30 ++++
drivers/char/tpm/tpm_crb.c | 81 +++++++++-
include/acpi/actbl3.h | 1 +
6 files changed, 426 insertions(+), 6 deletions(-)
create mode 100644 drivers/char/tpm/ffa_crb.c
create mode 100644 drivers/char/tpm/ffa_crb.h

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2.34.1