162306a36Sopenharmony_ci# SPDX-License-Identifier: GPL-2.0-only 262306a36Sopenharmony_ci# OP-TEE Trusted Execution Environment Configuration 362306a36Sopenharmony_ciconfig OPTEE 462306a36Sopenharmony_ci tristate "OP-TEE" 562306a36Sopenharmony_ci depends on HAVE_ARM_SMCCC 662306a36Sopenharmony_ci depends on MMU 762306a36Sopenharmony_ci help 862306a36Sopenharmony_ci This implements the OP-TEE Trusted Execution Environment (TEE) 962306a36Sopenharmony_ci driver. 1062306a36Sopenharmony_ci 1162306a36Sopenharmony_ciconfig OPTEE_INSECURE_LOAD_IMAGE 1262306a36Sopenharmony_ci bool "Load OP-TEE image as firmware" 1362306a36Sopenharmony_ci default n 1462306a36Sopenharmony_ci depends on OPTEE && ARM64 1562306a36Sopenharmony_ci help 1662306a36Sopenharmony_ci This loads the BL32 image for OP-TEE as firmware when the driver is 1762306a36Sopenharmony_ci probed. This returns -EPROBE_DEFER until the firmware is loadable from 1862306a36Sopenharmony_ci the filesystem which is determined by checking the system_state until 1962306a36Sopenharmony_ci it is in SYSTEM_RUNNING. This also requires enabling the corresponding 2062306a36Sopenharmony_ci option in Trusted Firmware for Arm. The documentation there explains 2162306a36Sopenharmony_ci the security threat associated with enabling this as well as 2262306a36Sopenharmony_ci mitigations at the firmware and platform level. 2362306a36Sopenharmony_ci https://trustedfirmware-a.readthedocs.io/en/latest/threat_model/threat_model.html 2462306a36Sopenharmony_ci 2562306a36Sopenharmony_ci Additional documentation on kernel security risks are at 2662306a36Sopenharmony_ci Documentation/staging/tee.rst. 27