Re: [XEN PATCH v11 14/14] docs: add Arm FF-A mediator

[Bertrand Marquis <Bertrand.Marquis@xxxxxxx>]

Hi Jens,

> On 31 Jul 2023, at 14:15, Jens Wiklander <jens.wiklander@xxxxxxxxxx> wrote:
> 
> Describes a FF-A version 1.1 [1] mediator to communicate with a Secure
> Partition in secure world.
> 
> [1] https://developer.arm.com/documentation/den0077/latest
> Signed-off-by: Jens Wiklander <jens.wiklander@xxxxxxxxxx>
> Reviewed-by: Henry Wang <Henry.Wang@xxxxxxx>

Reviewed-by: Bertrand Marquis <bertrand.marquis@xxxxxxx>

Cheers
Bertrand

> ---
> v10->v11
> - Add a CHANGELOG.md entry as requested
> ---
> CHANGELOG.md             |  3 ++-
> SUPPORT.md               |  9 +++++++++
> docs/man/xl.cfg.5.pod.in | 15 +++++++++++++++
> 3 files changed, 26 insertions(+), 1 deletion(-)
> 
> diff --git a/CHANGELOG.md b/CHANGELOG.md
> index 7d7e0590f8c6..f24c8c4b8011 100644
> --- a/CHANGELOG.md
> +++ b/CHANGELOG.md
> @@ -24,7 +24,8 @@ The format is based on [Keep a 
> Changelog](https://keepachangelog.com/en/1.0.0/)
>  - xl/libxl can customize SMBIOS strings for HVM guests.
>  - Add support for AVX512-FP16 on x86.
>  - On Arm, Xen supports guests running SVE/SVE2 instructions. (Tech Preview)
> -
> + - On Arm, add suport for Firmware Framework for Arm A-profile (FF-A) 
> Mediator
> +   (Tech Preview)
> 
> ## 
> [4.17.0](https://xenbits.xen.org/gitweb/?p=xen.git;a=shortlog;h=RELEASE-4.17.0)
>  - 2022-12-12
> 
> diff --git a/SUPPORT.md b/SUPPORT.md
> index 35a6249e03b2..fe512762cee7 100644
> --- a/SUPPORT.md
> +++ b/SUPPORT.md
> @@ -840,6 +840,15 @@ that covers the DMA of the device to be passed through.
> 
> No support for QEMU backends in a 16K or 64K domain.
> 
> +### ARM: Firmware Framework for Arm A-profile (FF-A) Mediator
> +
> +    Status, Arm64: Tech Preview
> +
> +There are still some code paths where a vCPU may hog a pCPU longer than
> +necessary. The FF-A mediator is not yet implemented for Arm32. Part of the
> +FF-A specification is not supported, see the top comment in
> +xen/arch/arm/tee/ffa.c for limitations.
> +
> ### ARM: Guest Device Tree support
> 
>     Status: Supported
> diff --git a/docs/man/xl.cfg.5.pod.in b/docs/man/xl.cfg.5.pod.in
> index a2bccd5b48a1..ec4864958e0e 100644
> --- a/docs/man/xl.cfg.5.pod.in
> +++ b/docs/man/xl.cfg.5.pod.in
> @@ -1656,6 +1656,21 @@ in OP-TEE.
> 
> This feature is a B<technology preview>.
> 
> +=item B<ffa>
> +
> +B<Arm only.> Allow a guest to communicate via FF-A with Secure Partitions
> +(SP), default false.
> +
> +Currently only a small subset of the FF-A specification is supported. Just
> +enough to communicate with OP-TEE. In general only direct messaging and
> +sharing memory with one SP. More advanced use cases where memory might be
> +shared or donated to multiple SPs are not supported.
> +
> +See L<https://developer.arm.com/documentation/den0077/latest> for more
> +information about FF-A.
> +
> +This feature is a B<technology preview>.
> +
> =back
> 
> =back
> -- 
> 2.34.1
>