Merge pull request #405 from vwadekar/tlkd-resume-fid-v3

TLKD: pass results with TLK_RESUME_FID function ID

services/spd/tlkd/tlkd_main.c

@@ -198,41 +198,6 @@ uint64_t tlkd_smc_handler(uint32_t smc_fid,
 
 		SMC_RET1(ns_cpu_context, x1);
 
-	/*
-	 * Request from non secure world to resume the preempted
-	 * Standard SMC call.
-	 */
-	case TLK_RESUME_FID:
-
-		/* RESUME should be invoked only by normal world */
-		if (!ns)
-			SMC_RET1(handle, SMC_UNK);
-
-		/*
-		 * This is a resume request from the non-secure client.
-		 * save the non-secure state and send the request to
-		 * the secure payload.
-		 */
-		assert(handle == cm_get_context(NON_SECURE));
-
-		/* Check if we are already preempted before resume */
-		if (!get_std_smc_active_flag(tlk_ctx.state))
-			SMC_RET1(handle, SMC_UNK);
-
-		cm_el1_sysregs_context_save(NON_SECURE);
-
-		/*
-		 * We are done stashing the non-secure context. Ask the
-		 * secure payload to do the work now.
-		 */
-
-		/* We just need to return to the preempted point in
-		 * SP and the execution will resume as normal.
-		 */
-		cm_el1_sysregs_context_restore(SECURE);
-		cm_set_next_eret_context(SECURE);
-		SMC_RET0(handle);
-
 	/*
 	 * This is a request from the non-secure context to:
 	 *
@@ -243,6 +208,7 @@ uint64_t tlkd_smc_handler(uint32_t smc_fid,
 	 *    Applications.
 	 * c. open/close sessions
 	 * d. issue commands to the Trusted Apps
+	 * e. resume the preempted standard SMC call.
 	 */
 	case TLK_REGISTER_LOGBUF:
 	case TLK_REGISTER_REQBUF:
@@ -250,6 +216,7 @@ uint64_t tlkd_smc_handler(uint32_t smc_fid,
 	case TLK_CLOSE_TA_SESSION:
 	case TLK_TA_LAUNCH_OP:
 	case TLK_TA_SEND_EVENT:
+	case TLK_RESUME_FID:
 
 		if (!ns)
 			SMC_RET1(handle, SMC_UNK);
@@ -262,9 +229,18 @@ uint64_t tlkd_smc_handler(uint32_t smc_fid,
 		 */
 		assert(handle == cm_get_context(NON_SECURE));
 
-		/* Check if we are already preempted */
-		if (get_std_smc_active_flag(tlk_ctx.state))
-			SMC_RET1(handle, SMC_UNK);
+		/*
+		 * Check if we are already processing a standard SMC
+		 * call. Of all the supported fids, only the "resume"
+		 * fid expects the flag to be set.
+		 */
+		if (smc_fid == TLK_RESUME_FID) {
+			if (!get_std_smc_active_flag(tlk_ctx.state))
+				SMC_RET1(handle, SMC_UNK);
+		} else {
+			if (get_std_smc_active_flag(tlk_ctx.state))
+				SMC_RET1(handle, SMC_UNK);
+		}
 
 		cm_el1_sysregs_context_save(NON_SECURE);