Hi Abdellatif,

On Fri, 10 Mar 2023 at 06:12, Abdellatif El Khlifi abdellatif.elkhlifi@arm.com wrote:

Adding support for Arm FF-A v1.0 (Arm Firmware Framework for Armv8-A) [A].

FF-A describes interfaces (ABIs) that standardize communication between the Secure World and Normal World. These interfaces enable a pair of software sandboxes to communicate with each other. A sandbox aka partition could be a VM in the Normal or Secure world, an application in S-EL0, or a Trusted OS in S-EL1.

FF-A is a discoverable bus and similar to architecture features. FF-A bus is discovered using ARM_SMCCC_FEATURES mechanism performed by the PSCI driver.

=> dm tree

Class     Index  Probed  Driver                Name

---

... firmware 0 [ + ] psci |-- psci ffa 0 [ ] arm_ffa | `-- arm_ffa ...

Clients are able to probe then use the FF-A bus by calling the DM class searching APIs (e.g: uclass_get_device_by_name).

This implementation of the specification provides support for Aarch64.

The FF-A driver uses the SMC ABIs defined by the FF-A specification to:

- Discover the presence of secure partitions (SPs) of interest
- Access an SP's service through communication protocols
  e.g. EFI MM communication protocol

The FF-A support provides the following features:

- Being generic by design and can be used by any Arm 64-bit platform
- The FF-A core driver
- The driver provides driver operations to be used by clients to access the FF-A bus
- FF-A driver can be compiled and used without EFI
- Support for SMCCCv1.2 x0-x17 registers
- Support for SMC32 calling convention
- Support for 32-bit and 64-bit FF-A direct messaging
- A new command called armffa is provided as an example of how to access the
  FF-A bus
- An FF-A Sandbox driver is provided with test cases
- Support for FF-A MM communication (compatible with EFI boot time)
- Enabling FF-A and MM communication in Corstone1000 platform as a use case

For more details about the FF-A core driver please refer to [B] and refer to [C] for how to use the armffa command.

Please find at [D] an example of the expected boot logs when enabling FF-A support for a platform. In this example the platform is Corstone1000. But it can be any Arm 64-bit platform.

Changelog of the major changes:

v9:

• integrate the FF-A bus discovery in the DM and use ARM_SMCCC_FEATURES for binding
• align FF-A sandbox driver with FF-A discovery through DM
• use DM class APIs to probe and interact with the FF-A bus (in FF-A MM comms, armffa command, sandbox tests)
• add documentation for the armffa command: doc/usage/cmd/armffa.rst
• introduce testcase for uuid_str_to_le_bin

This version looks a lot better. Things I noticed:

- fix up uclass to use operations - tidy up emulator binding to use DT

Both should be fairly easy.

Other than that I just have code-style nits.

Regards, Simon