[PATCH 2/2] KVM: arm64: support optional calls of FF-A v1.2

[Yeoreum Yun]

To use TPM drvier which uses CRB over FF-A with FFA_DIRECT_REQ2,
support the FF-A v1.2's optinal calls by querying whether
SPMC supports those.

Signed-off-by: Yeoreum Yun <yeoreum.yun at arm.com>
---
 arch/arm64/kvm/hyp/nvhe/ffa.c | 19 ++++++++++++++++++-
 1 file changed, 18 insertions(+), 1 deletion(-)

diff --git a/arch/arm64/kvm/hyp/nvhe/ffa.c b/arch/arm64/kvm/hyp/nvhe/ffa.c
index 0ae87ff61758..9ded1c6369b9 100644
--- a/arch/arm64/kvm/hyp/nvhe/ffa.c
+++ b/arch/arm64/kvm/hyp/nvhe/ffa.c
@@ -646,6 +646,22 @@ static void do_ffa_mem_reclaim(struct arm_smccc_1_2_regs *res,
 		ffa_to_smccc_res(res, ret);
 }
 
+static bool ffa_1_2_optional_calls_supported(u64 func_id)
+{
+	struct arm_smccc_1_2_regs res;
+
+	if (!smp_load_acquire(&has_version_negotiated) ||
+		(FFA_MINOR_VERSION(FFA_VERSION_1_2) < 2))
+		return false;
+
+	arm_smccc_1_2_smc(&(struct arm_smccc_1_2_regs) {
+		.a0 = FFA_FEATURES,
+		.a1 = func_id,
+	}, &res);
+
+	return res.a0 == FFA_SUCCESS;
+}
+
 /*
  * Is a given FFA function supported, either by forwarding on directly
  * or by handling at EL2?
@@ -678,12 +694,13 @@ 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 */
 	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 */
-		return false;
+		return ffa_1_2_optional_calls_supported(func_id);
 	}
 
 	return true;
-- 
LEVI:{C3F47F37-75D8-414A-A8BA-3980EC8A46D7}