Re: [XEN PATCH v7 02/20] xen/arm: tee: add a primitive FF-A mediator

[Julien Grall <julien@xxxxxxx>]

Hi,

I have only skimmed through the patch so far and I have one question below.

On 22/02/2023 15:32, Jens Wiklander wrote:
> Adds a FF-A version 1.1 [1] mediator to communicate with a Secure
> Partition in secure world.
>
> This commit brings in only the parts needed to negotiate FF-A version
> number with guest and SPMC.
>
> [1] https://developer.arm.com/documentation/den0077/e
> Signed-off-by: Jens Wiklander <jens.wiklander@xxxxxxxxxx>
> ---
>   xen/arch/arm/include/asm/domain.h  |   2 +-
>   xen/arch/arm/include/asm/psci.h    |   4 +
>   xen/arch/arm/include/asm/tee/ffa.h |  35 +++++
>   xen/arch/arm/tee/Kconfig           |  11 ++
>   xen/arch/arm/tee/Makefile          |   1 +
>   xen/arch/arm/tee/ffa.c             | 217 +++++++++++++++++++++++++++++
>   xen/arch/arm/vsmc.c                |  17 ++-
>   xen/include/public/arch-arm.h      |   1 +
>   8 files changed, 284 insertions(+), 4 deletions(-)
>   create mode 100644 xen/arch/arm/include/asm/tee/ffa.h
>   create mode 100644 xen/arch/arm/tee/ffa.c
>
> diff --git a/xen/arch/arm/include/asm/domain.h 
> b/xen/arch/arm/include/asm/domain.h
> index 0e310601e846..754daa8efa04 100644
> --- a/xen/arch/arm/include/asm/domain.h
> +++ b/xen/arch/arm/include/asm/domain.h
> @@ -110,7 +110,7 @@ struct arch_domain
>       struct vpl011 vpl011;
>   #endif
>   
> -#ifdef CONFIG_TEE
> +#if defined(CONFIG_TEE) || defined(CONFIG_FFA)
I am confused, AFAICT, you are implementing FFA using TEE, so doesn't 
this mean that CONFIG_FFA depends on CONFIG_TEE?
If so, then you should not need the extra defined here.

>       void *tee;
>   #endif
--
Julien Grall