Fix SMCCC_ARCH_SOC_ID implementation

Commit 0e753437

 ("Implement SMCCC_ARCH_SOC_ID SMC call") executes
and return the result of SMCCC_ARCH_SOC_ID(soc_id_type) to the
SMCCC_ARCH_FEATURES(SMCCC_ARCH_SOC_ID) itself. Moreover it expect to
pass soc_id_type for SMCCC_ARCH_FEATURES(SMCCC_ARCH_SOC_ID) which is
incorrect.

Fix the implementation by returning SMC_OK for
SMCCC_ARCH_FEATURES(SMCCC_ARCH_SOC_ID) always and move the current
implementation under "smccc_arch_id" function which gets called from
SMC handler on receiving "SMCCC_ARCH_SOC_ID" command.

This change is tested over linux operating system

Change-Id: I61a980045081eae786b907d408767ba9ecec3468
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
Signed-off-by: Manish V Badarkhe <Manish.Badarkhe@arm.com>

services/arm_arch_svc/arm_arch_svc_setup.c

@@ -19,20 +19,13 @@ static int32_t smccc_version(void)
 	return MAKE_SMCCC_VERSION(SMCCC_MAJOR_VERSION, SMCCC_MINOR_VERSION);
 }
 
-static int32_t smccc_arch_features(u_register_t arg1, u_register_t arg2)
+static int32_t smccc_arch_features(u_register_t arg1)
 {
 	switch (arg1) {
 	case SMCCC_VERSION:
 	case SMCCC_ARCH_FEATURES:
-		return SMC_OK;
 	case SMCCC_ARCH_SOC_ID:
-		if (arg2 == SMCCC_GET_SOC_REVISION) {
-			return plat_get_soc_revision();
-		}
-		if (arg2 == SMCCC_GET_SOC_VERSION) {
-			return plat_get_soc_version();
-		}
-		return SMC_ARCH_CALL_INVAL_PARAM;
+		return SMC_OK;
 #if WORKAROUND_CVE_2017_5715
 	case SMCCC_ARCH_WORKAROUND_1:
 		if (check_wa_cve_2017_5715() == ERRATA_NOT_APPLIES)
@@ -87,6 +80,19 @@ static int32_t smccc_arch_features(u_register_t arg1, u_register_t arg2)
 	}
 }
 
+/* return soc revision or soc version on success otherwise
+ * return invalid parameter */
+static int32_t smccc_arch_id(u_register_t arg1)
+{
+	if (arg1 == SMCCC_GET_SOC_REVISION) {
+		return plat_get_soc_revision();
+	}
+	if (arg1 == SMCCC_GET_SOC_VERSION) {
+		return plat_get_soc_version();
+	}
+	return SMC_ARCH_CALL_INVAL_PARAM;
+}
+
 /*
  * Top-level Arm Architectural Service SMC handler.
  */
@@ -103,7 +109,9 @@ static uintptr_t arm_arch_svc_smc_handler(uint32_t smc_fid,
 	case SMCCC_VERSION:
 		SMC_RET1(handle, smccc_version());
 	case SMCCC_ARCH_FEATURES:
-		SMC_RET1(handle, smccc_arch_features(x1, x2));
+		SMC_RET1(handle, smccc_arch_features(x1));
+	case SMCCC_ARCH_SOC_ID:
+		SMC_RET1(handle, smccc_arch_id(x1));
 #if WORKAROUND_CVE_2017_5715
 	case SMCCC_ARCH_WORKAROUND_1:
 		/*