From: Per Larsen <perlarsen@google.com>

FF-A 1.2 adds the DIRECT_REQ2 messaging interface which is similar to
the existing FFA_MSG_SEND_DIRECT_{REQ,RESP} functions and can use the
existing handler function. Add support for FFA_MSG_SEND_DIRECT_REQ2 in
the host ffa handler.

Reviewed-by: Yeoreum Yun <yeoreum.yun@arm.com>
Signed-off-by: Per Larsen <perlarsen@google.com>
---
 arch/arm64/kvm/hyp/nvhe/ffa.c | 15 +++++++++++++--
 1 file changed, 13 insertions(+), 2 deletions(-)

diff --git a/arch/arm64/kvm/hyp/nvhe/ffa.c b/arch/arm64/kvm/hyp/nvhe/ffa.c
index a38a3ab497e5eac11777109684a33f02d88d09a1..c794802bda589b315faf978086ad164a2aee510a 100644
--- a/arch/arm64/kvm/hyp/nvhe/ffa.c
+++ b/arch/arm64/kvm/hyp/nvhe/ffa.c
@@ -683,8 +683,10 @@ static bool ffa_call_supported(u64 func_id)
 	case FFA_NOTIFICATION_SET:
 	case FFA_NOTIFICATION_GET:
 	case FFA_NOTIFICATION_INFO_GET:
+		return false;
 	/* Optional interfaces added in FF-A 1.2 */
 	case FFA_MSG_SEND_DIRECT_REQ2:		/* Optional per 7.5.1 */
+		return hyp_ffa_version >= FFA_VERSION_1_2;
 	case FFA_MSG_SEND_DIRECT_RESP2:		/* Optional per 7.5.1 */
 	case FFA_CONSOLE_LOG:			/* Optional per 13.1: not in Table 13.1 */
 	case FFA_PARTITION_INFO_GET_REGS:	/* Optional for virtual instances per 13.1 */
@@ -866,12 +868,16 @@ static void do_ffa_direct_msg(struct arm_smccc_1_2_regs *res,
 			      struct kvm_cpu_context *ctxt,
 			      u64 vm_handle)
 {
+	DECLARE_REG(u64, func_id, ctxt, 0);
 	DECLARE_REG(u32, flags, ctxt, 2);
 
 	struct arm_smccc_1_2_regs *args = (void *)&ctxt->regs.regs[0];
 
-	/* filter out framework messages */
-	if (FIELD_GET(FFA_MSG_FLAGS_MSG_TYPE, flags)) {
+	/*
+	 * filter out framework messages.
+	 * FFA_MSG_SEND_DIRECT_REQ2 is only for partition messages.
+	 */
+	if (func_id != FFA_MSG_SEND_DIRECT_REQ2 && FIELD_GET(FFA_MSG_FLAGS_MSG_TYPE, flags)) {
 		ffa_to_smccc_error(res, FFA_RET_INVALID_PARAMETERS);
 		return;
 	}
@@ -937,6 +943,10 @@ bool kvm_host_ffa_handler(struct kvm_cpu_context *host_ctxt, u32 func_id)
 	case FFA_PARTITION_INFO_GET:
 		do_ffa_part_get(&res, host_ctxt);
 		goto out_handled;
+	case FFA_MSG_SEND_DIRECT_REQ2:
+		if (!ffa_call_supported(func_id))
+			goto out_not_supported;
+		fallthrough;
 	case FFA_MSG_SEND_DIRECT_REQ:
 	case FFA_FN64_MSG_SEND_DIRECT_REQ:
 
@@ -947,6 +957,7 @@ bool kvm_host_ffa_handler(struct kvm_cpu_context *host_ctxt, u32 func_id)
 	if (ffa_call_supported(func_id))
 		return false; /* Pass through */
 
+out_not_supported:
 	ffa_to_smccc_error(&res, FFA_RET_NOT_SUPPORTED);
 out_handled:
 	ffa_set_retval(host_ctxt, &res);

-- 
2.52.0.rc1.455.g30608eb744-goog

On Wed, Nov 19, 2025 at 02:07:54AM +0000, Per Larsen via B4 Relay wrote:
> From: Per Larsen <perlarsen@google.com>
> 
> FF-A 1.2 adds the DIRECT_REQ2 messaging interface which is similar to
> the existing FFA_MSG_SEND_DIRECT_{REQ,RESP} functions and can use the
> existing handler function. Add support for FFA_MSG_SEND_DIRECT_REQ2 in
> the host ffa handler.
> 
> Reviewed-by: Yeoreum Yun <yeoreum.yun@arm.com>
> Signed-off-by: Per Larsen <perlarsen@google.com>
> ---
>  arch/arm64/kvm/hyp/nvhe/ffa.c | 15 +++++++++++++--
>  1 file changed, 13 insertions(+), 2 deletions(-)
> 
> diff --git a/arch/arm64/kvm/hyp/nvhe/ffa.c b/arch/arm64/kvm/hyp/nvhe/ffa.c
> index a38a3ab497e5eac11777109684a33f02d88d09a1..c794802bda589b315faf978086ad164a2aee510a 100644
> --- a/arch/arm64/kvm/hyp/nvhe/ffa.c
> +++ b/arch/arm64/kvm/hyp/nvhe/ffa.c
> @@ -683,8 +683,10 @@ static bool ffa_call_supported(u64 func_id)
>  	case FFA_NOTIFICATION_SET:
>  	case FFA_NOTIFICATION_GET:
>  	case FFA_NOTIFICATION_INFO_GET:
> +		return false;
>  	/* Optional interfaces added in FF-A 1.2 */
>  	case FFA_MSG_SEND_DIRECT_REQ2:		/* Optional per 7.5.1 */
> +		return hyp_ffa_version >= FFA_VERSION_1_2;

You might as well just move this to the end and avoid having to add the
'return false' above.

>  	case FFA_MSG_SEND_DIRECT_RESP2:		/* Optional per 7.5.1 */
>  	case FFA_CONSOLE_LOG:			/* Optional per 13.1: not in Table 13.1 */
>  	case FFA_PARTITION_INFO_GET_REGS:	/* Optional for virtual instances per 13.1 */
> @@ -866,12 +868,16 @@ static void do_ffa_direct_msg(struct arm_smccc_1_2_regs *res,
>  			      struct kvm_cpu_context *ctxt,
>  			      u64 vm_handle)
>  {
> +	DECLARE_REG(u64, func_id, ctxt, 0);
>  	DECLARE_REG(u32, flags, ctxt, 2);
>  
>  	struct arm_smccc_1_2_regs *args = (void *)&ctxt->regs.regs[0];
>  
> -	/* filter out framework messages */
> -	if (FIELD_GET(FFA_MSG_FLAGS_MSG_TYPE, flags)) {
> +	/*
> +	 * filter out framework messages.
> +	 * FFA_MSG_SEND_DIRECT_REQ2 is only for partition messages.
> +	 */
> +	if (func_id != FFA_MSG_SEND_DIRECT_REQ2 && FIELD_GET(FFA_MSG_FLAGS_MSG_TYPE, flags)) {
>  		ffa_to_smccc_error(res, FFA_RET_INVALID_PARAMETERS);
>  		return;
>  	}

It would probably be better to switch the polarity of this check so that
you look at flags if FFA_MSG_SEND_DIRECT_REQ or
FFA_FN64_MSG_SEND_DIRECT_REQ rather than if !REQ2.

and again, I'm not seeing what the 'vm_handle' argument is doing here.

Will