plat/arm: juno: Implement methods to retrieve soc-id information

Implemented platform functions to retrieve the soc-id information
for juno platform

Change-Id: Ie677120710b45e202a2d63a954459ece8a64b353
Signed-off-by: Manish V Badarkhe <Manish.Badarkhe@arm.com>

plat/arm/board/juno/juno_common.c

 /*
- * Copyright (c) 2015-2019, ARM Limited and Contributors. All rights reserved.
+ * Copyright (c) 2015-2020, ARM Limited and Contributors. All rights reserved.
  *
  * SPDX-License-Identifier: BSD-3-Clause
  */
 
+#include <lib/smccc.h>
 #include <platform_def.h>
+#include <services/arm_arch_svc.h>
+
 #include <plat/arm/common/plat_arm.h>
 
 /*
@@ -91,3 +94,40 @@ const mmap_region_t plat_arm_mmap[] = {
 #endif
 
 ARM_CASSERT_MMAP
+
+/*****************************************************************************
+ * plat_is_smccc_feature_available() - This function checks whether SMCCC
+ *                                     feature is availabile for platform.
+ * @fid: SMCCC function id
+ *
+ * Return SMC_ARCH_CALL_SUCCESS if SMCCC feature is available and
+ * SMC_ARCH_CALL_NOT_SUPPORTED otherwise.
+ *****************************************************************************/
+int32_t plat_is_smccc_feature_available(u_register_t fid)
+{
+	switch (fid) {
+	case SMCCC_ARCH_SOC_ID:
+		return SMC_ARCH_CALL_SUCCESS;
+	default:
+		return SMC_ARCH_CALL_NOT_SUPPORTED;
+	}
+}
+
+/* Get SOC version */
+int32_t plat_get_soc_version(void)
+{
+	return (int32_t)
+		((ARM_SOC_IDENTIFICATION_CODE << ARM_SOC_IDENTIFICATION_SHIFT)
+		 | (ARM_SOC_CONTINUATION_CODE << ARM_SOC_CONTINUATION_SHIFT)
+		 | JUNO_SOC_ID);
+}
+
+/* Get SOC revision */
+int32_t plat_get_soc_revision(void)
+{
+	unsigned int sys_id;
+
+	sys_id = mmio_read_32(V2M_SYSREGS_BASE + V2M_SYS_ID);
+	return (int32_t)((sys_id >> V2M_SYS_ID_REV_SHIFT) &
+			V2M_SYS_ID_REV_MASK);
+}

plat/arm/board/juno/juno_def.h

 /*
- * Copyright (c) 2014-2019, ARM Limited and Contributors. All rights reserved.
+ * Copyright (c) 2014-2020, ARM Limited and Contributors. All rights reserved.
  *
  * SPDX-License-Identifier: BSD-3-Clause
  */
@@ -9,6 +9,11 @@
 
 #include <lib/utils_def.h>
 
+/******************************************************************************
+ * Definition of platform soc id
+ *****************************************************************************/
+#define JUNO_SOC_ID     1
+
 /*******************************************************************************
  * Juno memory map related constants
  ******************************************************************************/