Re: [PATCH v6 00/10] introduce Arm FF-A support

Ilias Apalodimas
2022-10-13T12:07:50Z

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