[PATCH v4 7/7] KVM: arm64: Support FFA_NOTIFICATION_INFO_GET in host handler

[Sebastian Ene]

Allow the host to query the FF-A notifiction status and proxy the info
get message to Trustzone. Make sure that the SBZ fields are enforced.

Signed-off-by: Sebastian Ene <sebastianene at google.com>
---
 arch/arm64/kvm/hyp/nvhe/ffa.c | 19 +++++++++++++++++--
 1 file changed, 17 insertions(+), 2 deletions(-)

diff --git a/arch/arm64/kvm/hyp/nvhe/ffa.c b/arch/arm64/kvm/hyp/nvhe/ffa.c
index de4794338388..ffb6d44b5010 100644
--- a/arch/arm64/kvm/hyp/nvhe/ffa.c
+++ b/arch/arm64/kvm/hyp/nvhe/ffa.c
@@ -715,8 +715,6 @@ static bool ffa_call_supported(u64 func_id)
 	case FFA_RXTX_MAP:
 	case FFA_MEM_DONATE:
 	case FFA_MEM_RETRIEVE_REQ:
-       /* Optional notification interfaces added in FF-A 1.1 */
-	case FFA_NOTIFICATION_INFO_GET:
 	/* 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 */
@@ -1026,6 +1024,20 @@ static void do_ffa_notif_get(struct arm_smccc_1_2_regs *res,
 	hyp_smccc_1_2_smc(args, res);
 }
 
+static void do_ffa_notif_info_get(struct arm_smccc_1_2_regs *res,
+				  struct kvm_cpu_context *ctxt)
+{
+	struct arm_smccc_1_2_regs *args;
+
+	if (ffa_check_unused_args_sbz(ctxt, 1)) {
+		ffa_to_smccc_res(res, FFA_RET_INVALID_PARAMETERS);
+		return;
+	}
+
+	args = (void *)&ctxt->regs.regs[0];
+	hyp_smccc_1_2_smc(args, res);
+}
+
 bool kvm_host_ffa_handler(struct kvm_cpu_context *host_ctxt, u32 func_id)
 {
 	struct arm_smccc_1_2_regs res;
@@ -1100,6 +1112,9 @@ bool kvm_host_ffa_handler(struct kvm_cpu_context *host_ctxt, u32 func_id)
 	case FFA_NOTIFICATION_GET:
 		do_ffa_notif_get(&res, host_ctxt);
 		goto out_handled;
+	case FFA_NOTIFICATION_INFO_GET:
+		do_ffa_notif_info_get(&res, host_ctxt);
+		goto out_handled;
 	}
 
 	if (ffa_call_supported(func_id))
-- 
2.54.0.1136.gdb2ca164c4-goog