refactor(smccc): move debugfs to vendor el3 calls

Move debugfs to Vendor-Specific EL3 Monitor Service Calls.
Function Identifier for Vendor-Specific EL3 Monitor Service is '7' and
allocated subranges of Function identifiers to different services are:

0x87000000-0x8700FFFF-SMC32: Vendor-Specific EL3 Monitor Service Calls
0xC7000000-0xC700FFFF-SMC64: Vendor-Specific EL3 Monitor Service Calls

Amend Debugfs FID's to use this range and id.

Add a deprecation notice to inform debugfs moved from arm-sip range to
Vendor-Specific EL3 range. Debugfs support from arm-sip range will be
removed and will not be available after TF-A 2.12 release.

Reference to debugfs component level documentation:
https://trustedfirmware-a.readthedocs.io/en/latest/components/debugfs-design.html#overview

Change-Id: I97a50170178f361f70c95ed0049bc4e278de59d7
Signed-off-by: Govindraj Raja <govindraj.raja@arm.com>
diff --git a/services/el3/ven_el3_svc.c b/services/el3/ven_el3_svc.c
index 327878f..de003ae 100644
--- a/services/el3/ven_el3_svc.c
+++ b/services/el3/ven_el3_svc.c
@@ -8,6 +8,7 @@
 
 #include <common/debug.h>
 #include <common/runtime_svc.h>
+#include <lib/debugfs.h>
 #include <services/ven_el3_svc.h>
 #include <tools_share/uuid.h>
 
@@ -18,6 +19,12 @@
 
 static int ven_el3_svc_setup(void)
 {
+#if USE_DEBUGFS
+	if (debugfs_smc_setup() != 0) {
+		return 1;
+	}
+#endif /* USE_DEBUGFS */
+
 	return 0;
 }
 
@@ -33,6 +40,17 @@
 			void *handle,
 			u_register_t flags)
 {
+#if USE_DEBUGFS
+	/*
+	 * Dispatch debugfs calls to debugfs SMC handler and return its
+	 * return value.
+	 */
+	if (is_debugfs_fid(smc_fid)) {
+		return debugfs_smc_handler(smc_fid, x1, x2, x3, x4, cookie,
+			handle, flags);
+	}
+#endif /* USE_DEBUGFS */
+
 	switch (smc_fid) {
 	case VEN_EL3_SVC_UID:
 		/* Return UID to the caller */
@@ -42,7 +60,7 @@
 		SMC_RET2(handle, VEN_EL3_SVC_VERSION_MAJOR, VEN_EL3_SVC_VERSION_MINOR);
 		break;
 	default:
-		WARN("Unimplemented Vendor specific EL3 Service call: 0x%x\n", smc_fid);
+		WARN("Unimplemented vendor-specific EL3 Service call: 0x%x\n", smc_fid);
 		SMC_RET1(handle, SMC_UNK);
 		break;
 	}