Merge branch '2023-08-08-introuce-Arm-FF-A-support'

To quote the author:
Adding support for Arm FF-A v1.0 (Arm Firmware Framework for Armv8-A) [A].

FF-A specifies interfaces that enable a pair of software execution
environments aka partitions to communicate with each other. A 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_first_device).

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
    - FF-A support 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
    - Support for FF-A MM communication (compatible with EFI boot time)
    - Enabling FF-A and MM communication in Corstone1000 platform as a use case
    - A Uclass driver providing generic FF-A methods.
    - An Arm FF-A device driver providing Arm-specific methods and reusing the Uclass methods.
    - A sandbox emulator for Arm FF-A, emulates the FF-A side of the Secure World and provides
      FF-A ABIs inspection methods.
    - An FF-A sandbox device driver for FF-A communication with the emulated Secure World.
      The driver leverages the FF-A Uclass to establish FF-A communication.
    - Sandbox FF-A test cases.
    - A new command called armffa is provided as an example of how to access the
      FF-A bus

For more details about the FF-A support 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.

More details:

[A]: https://developer.arm.com/documentation/den0077/latest/
[B]: doc/arch/arm64.ffa.rst
[C]: doc/usage/cmd/armffa.rst
[D]: example of boot logs when enabling FF-A

1 files changed, 94 insertions, 0 deletions

diff --git a/doc/usage/cmd/armffa.rst b/doc/usage/cmd/armffa.rst
new file mode 100644
index 00000000000..13fa90c1290
--- /dev/null
+++ b/doc/usage/cmd/armffa.rst
@@ -0,0 +1,94 @@
+.. SPDX-License-Identifier: GPL-2.0+
+.. Copyright 2022-2023 Arm Limited and/or its affiliates <[email protected]>
+
+armffa command
+==============
+
+Synopsis
+--------
+
+::
+
+   armffa [sub-command] [arguments]
+
+   sub-commands:
+
+        getpart [partition UUID]
+
+            lists the partition(s) info
+
+        ping [partition ID]
+
+            sends a data pattern to the specified partition
+
+        devlist
+
+            displays information about the FF-A device/driver
+
+Description
+-----------
+
+armffa is a command showcasing how to use the FF-A bus and how to invoke its operations.
+
+This provides a guidance to the client developers on how to call the FF-A bus interfaces.
+
+The command also allows to gather secure partitions information and ping these  partitions.
+
+The command is also helpful in testing the communication with secure partitions.
+
+Example
+-------
+
+The following examples are run on Corstone-1000 platform.
+
+* ping
+
+::
+
+   corstone1000# armffa ping 0x8003
+   SP response:
+   [LSB]
+   fffffffe
+   0
+   0
+   0
+   0
+
+* ping (failure case)
+
+::
+
+   corstone1000# armffa ping 0
+   Sending direct request error (-22)
+
+* getpart
+
+::
+
+   corstone1000# armffa getpart 33d532ed-e699-0942-c09c-a798d9cd722d
+   Partition: id = 8003 , exec_ctxt 1 , properties 3
+
+* getpart (failure case)
+
+::
+
+   corstone1000# armffa getpart 33d532ed-e699-0942-c09c-a798d9cd7221
+   INVALID_PARAMETERS: Unrecognized UUID
+   Failure in querying partitions count (error code: -22)
+
+* devlist
+
+::
+
+   corstone1000# armffa devlist
+   device name arm_ffa, dev 00000000fdf41c30, driver name arm_ffa, ops 00000000fffc0e98
+
+Configuration
+-------------
+
+The command is available if CONFIG_CMD_ARMFFA=y and CONFIG_ARM_FFA_TRANSPORT=y.
+
+Return value
+------------
+
+The return value $? is 0 (true) on success, 1 (false) on failure.