blob: fc668c109d6dbc0fd864d521ee3d285998458ede [file] [log] [blame]
# SPDX-License-Identifier: GPL-2.0
config ARM_FFA_TRANSPORT
bool "Enable Arm Firmware Framework for Armv8-A driver"
depends on DM && (ARM64 || SANDBOX)
select ARM_SMCCC if !SANDBOX
select ARM_SMCCC_FEATURES if !SANDBOX
select LIB_UUID
select DEVRES
help
The Firmware Framework for Arm A-profile processors (FF-A)
describes interfaces (ABIs) that standardize communication
between the Secure World and Normal World leveraging TrustZone
technology.
The FF-A support in U-Boot is based on FF-A specification v1.0 and uses SMC32
calling convention.
FF-A specification:
https://developer.arm.com/documentation/den0077/a/?lang=en
In U-Boot FF-A design, FF-A is considered as a discoverable bus.
FF-A bus is discovered using ARM_SMCCC_FEATURES mechanism performed
by the PSCI driver.
The Secure World is considered as one entity to communicate with
using the FF-A bus.
FF-A communication is handled by one device and one instance (the bus).
The FF-A support on U-Boot takes care of all the interactions between Normal
world and Secure World.
Generic FF-A methods are implemented in the Uclass (arm-ffa-uclass.c).
Arm specific methods are implemented in the Arm driver (arm-ffa.c).
FF-A sandbox is provided to run FF-A under sandbox and allows to test the FF-A Uclass.
Sandbox support includes an emulator for Arm FF-A which emulates the FF-A side of
the Secure World and provides FF-A ABIs inspection methods (ffa-emul-uclass.c).
An FF-A sandbox driver is also provided for FF-A communication with the emulated
Secure World (sandbox_ffa.c).
For more details about the FF-A support, please refer to doc/arch/arm64.ffa.rst