feat(drtm): add standard DRTM service

Added a dummy DRTM setup function and also, introduced DRTM SMCs
handling as per DRTM spec [1]. Few basic SMCs are handled in this
change such as ARM_DRTM_SVC_VERSION and ARM_DRTM_SVC_FEATURES
that returns DRTM version and functions ids supported respectively,
and others are dummy for now.

[1]: https://developer.arm.com/documentation/den0113/latest

Signed-off-by: Manish V Badarkhe <manish.badarkhe@arm.com>
Signed-off-by: Lucian Paul-Trifu <lucian.paultrifu@gmail.com>
Change-Id: I8c7afe920c78e064cbab2298f59e6837c70ba8ff
diff --git a/services/std_svc/std_svc_setup.c b/services/std_svc/std_svc_setup.c
index b1e3db9..08d16e2 100644
--- a/services/std_svc/std_svc_setup.c
+++ b/services/std_svc/std_svc_setup.c
@@ -13,6 +13,7 @@
 #include <lib/pmf/pmf.h>
 #include <lib/psci/psci.h>
 #include <lib/runtime_instr.h>
+#include <services/drtm_svc.h>
 #include <services/pci_svc.h>
 #include <services/rmmd_svc.h>
 #include <services/sdei.h>
@@ -75,6 +76,12 @@
 
 	trng_setup();
 
+#if DRTM_SUPPORT
+	if (drtm_setup() != 0) {
+		ret = 1;
+	}
+#endif /* DRTM_SUPPORT */
+
 	return ret;
 }
 
@@ -186,6 +193,13 @@
 	}
 #endif
 
+#if DRTM_SUPPORT
+	if (is_drtm_fid(smc_fid)) {
+		return drtm_smc_handler(smc_fid, x1, x2, x3, x4, cookie, handle,
+					flags);
+	}
+#endif /* DRTM_SUPPORT */
+
 	switch (smc_fid) {
 	case ARM_STD_SVC_CALL_COUNT:
 		/*