Hi Abdellatif,

On Thu, Oct 13, 2022 at 11:38:47AM +0100, Abdellatif El Khlifi wrote:

Adding support for Arm FF-A v1.0 (Arm Firmware Framework for Armv8-A) [6].

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.

The FF-A transport is implemented as a data bus and a core driver is provided.

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 FF-A bus is discoverable on demand at runtime
• The driver provides callbacks 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
• 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
• Enabling FF-A and MM communication in Corstone1000 platform

For more details about the FF-A core driver please refer to [7].

Please find at [8] 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:

v6:

• remove clearing x0-x17 registers after SMC calls
• drop use of EFI runtime support for FF-A (We decided with Linaro to add this later)

Thanks! This makes the whole process way way easier. I am bit overloaded atm but I'll try squeezing in reviewing these patches

• drop discovery from initcalls (discovery will be on demand by FF-A users)
• add FF-A runtime discovery at MM communication level
• update the documentation and move it to doc/arch/arm64.ffa.rst

v5: [5]

• move changelogs in each commit to the changes section

v4: [4]

• add FF-A support README (doc/README.ffa.drv)
• improving error handling by mapping the FF-A errors to standard errors and logs
• replacing panics with an error log
• align sandbox driver and tests with the new FF-A driver interfaces

and new way of error handling

[...]

Thanks /Ilias