diff --git a/plat/arm/css/sgi/aarch64/sgi_helper.S b/plat/arm/css/sgi/aarch64/sgi_helper.S
new file mode 100644
index 0000000..c435d8b
--- /dev/null
+++ b/plat/arm/css/sgi/aarch64/sgi_helper.S
@@ -0,0 +1,49 @@
+/*
+ * Copyright (c) 2018, ARM Limited and Contributors. All rights reserved.
+ *
+ * SPDX-License-Identifier: BSD-3-Clause
+ */
+
+#include <arch.h>
+#include <asm_macros.S>
+#include <platform_def.h>
+
+	.globl	plat_is_my_cpu_primary
+	.globl	plat_arm_calc_core_pos
+
+	/* -----------------------------------------------------
+	 * unsigned int plat_is_my_cpu_primary (void);
+	 *
+	 * Find out whether the current cpu is the primary
+	 * cpu (applicable only after a cold boot)
+	 * -----------------------------------------------------
+	 */
+func plat_is_my_cpu_primary
+	mov	x9, x30
+	bl	plat_my_core_pos
+	ldr	x1, =SGI_BOOT_CFG_ADDR
+	ldr	x1, [x1]
+	ubfx	x1, x1, #PLAT_CSS_PRIMARY_CPU_SHIFT, \
+			#PLAT_CSS_PRIMARY_CPU_BIT_WIDTH
+	cmp	x0, x1
+	cset	w0, eq
+	ret	x9
+endfunc plat_is_my_cpu_primary
+
+	/* -----------------------------------------------------
+	*  unsigned int plat_arm_calc_core_pos(uint64_t mpidr)
+	*  Helper function to calculate the core position.
+	* -----------------------------------------------------
+	*/
+func plat_arm_calc_core_pos
+	mrs     x2, mpidr_el1
+	ands    x2, x2, #MPIDR_MT_MASK
+	beq     1f
+	lsr     x0, x0, #MPIDR_AFF1_SHIFT
+1:
+	and	x1, x0, #MPIDR_CPU_MASK
+	and	x0, x0, #MPIDR_CLUSTER_MASK
+	add	x0, x1, x0, LSR #6
+	and     x0, x0, #MPIDR_AFFLVL_MASK
+	ret
+endfunc plat_arm_calc_core_pos
diff --git a/plat/arm/css/sgi/include/plat_macros.S b/plat/arm/css/sgi/include/plat_macros.S
new file mode 100644
index 0000000..fe9a66c
--- /dev/null
+++ b/plat/arm/css/sgi/include/plat_macros.S
@@ -0,0 +1,23 @@
+/*
+ * Copyright (c) 2018, ARM Limited and Contributors. All rights reserved.
+ *
+ * SPDX-License-Identifier: BSD-3-Clause
+ */
+#ifndef __PLAT_MACROS_S__
+#define __PLAT_MACROS_S__
+
+#include <css_macros.S>
+
+/* ---------------------------------------------
+ * The below required platform porting macro
+ * prints out relevant platform registers
+ * whenever an unhandled exception is taken in
+ * BL31.
+ *
+ * There are currently no platform specific regs
+ * to print.
+ * ---------------------------------------------
+ */
+	.macro plat_crash_print_regs
+	.endm
+#endif /* __PLAT_MACROS_S__ */
diff --git a/plat/arm/css/sgi/include/platform_def.h b/plat/arm/css/sgi/include/platform_def.h
new file mode 100644
index 0000000..62f4059
--- /dev/null
+++ b/plat/arm/css/sgi/include/platform_def.h
@@ -0,0 +1,94 @@
+/*
+ * Copyright (c) 2018, ARM Limited and Contributors. All rights reserved.
+ *
+ * SPDX-License-Identifier: BSD-3-Clause
+ */
+
+#ifndef __PLATFORM_DEF_H__
+#define __PLATFORM_DEF_H__
+
+#include <arm_def.h>
+#include <board_arm_def.h>
+#include <board_css_def.h>
+#include <common_def.h>
+#include <css_def.h>
+#include <soc_css_def.h>
+
+#define CSS_SGI_MAX_CORES_PER_CLUSTER	4
+
+/* CPU topology */
+#define PLAT_ARM_CLUSTER_COUNT		2
+#define PLATFORM_CORE_COUNT		(PLAT_ARM_CLUSTER_COUNT *	\
+					CSS_SGI_MAX_CORES_PER_CLUSTER)
+
+#if ARM_BOARD_OPTIMISE_MEM
+
+#if defined(IMAGE_BL31) || defined(IMAGE_BL32)
+# define PLAT_ARM_MMAP_ENTRIES		6
+# define MAX_XLAT_TABLES		4
+#else
+# define PLAT_ARM_MMAP_ENTRIES		10
+# define MAX_XLAT_TABLES		5
+#endif
+
+#if TRUSTED_BOARD_BOOT
+# define PLAT_ARM_MAX_BL1_RW_SIZE	0xA000
+#else
+# define PLAT_ARM_MAX_BL1_RW_SIZE	0x6000
+#endif
+
+#if TRUSTED_BOARD_BOOT
+# define PLAT_ARM_MAX_BL2_SIZE		0x1D000
+#else
+# define PLAT_ARM_MAX_BL2_SIZE		0xC000
+#endif
+
+#endif /* ARM_BOARD_OPTIMISE_MEM */
+
+#define PLAT_ARM_NSTIMER_FRAME_ID	0
+
+#define PLAT_CSS_MHU_BASE		0x45000000
+
+#define PLAT_ARM_TRUSTED_ROM_BASE	0x0
+#define PLAT_ARM_TRUSTED_ROM_SIZE	0x00080000	/* 512KB */
+
+#define PLAT_MAX_PWR_LVL		1
+
+#define PLAT_ARM_G1S_IRQS		ARM_G1S_IRQS,			\
+					CSS_IRQ_MHU
+
+#define PLAT_ARM_G0_IRQS		ARM_G0_IRQS
+
+#define PLAT_ARM_G1S_IRQ_PROPS(grp)	CSS_G1S_IRQ_PROPS(grp)
+#define PLAT_ARM_G0_IRQ_PROPS(grp)	ARM_G0_IRQ_PROPS(grp)
+
+#define CSS_SGI_DEVICE_BASE	(0x20000000)
+#define CSS_SGI_DEVICE_SIZE	(0x20000000)
+#define CSS_SGI_MAP_DEVICE	MAP_REGION_FLAT(		\
+					CSS_SGI_DEVICE_BASE,	\
+					CSS_SGI_DEVICE_SIZE,	\
+					MT_DEVICE | MT_RW | MT_SECURE)
+
+#define PLAT_CSS_SCP_COM_SHARED_MEM_BASE	0x45400000
+#define SGI_BOOT_CFG_ADDR			0x45410000
+#define PLAT_CSS_PRIMARY_CPU_SHIFT		8
+#define PLAT_CSS_PRIMARY_CPU_BIT_WIDTH		6
+
+/* GIC related constants */
+#define PLAT_ARM_GICD_BASE		0x30000000
+#define PLAT_ARM_GICC_BASE		0x2C000000
+#define PLAT_ARM_GICR_BASE		0x300C0000
+
+/* Platform ID address */
+#define SSC_VERSION                     (SSC_REG_BASE + SSC_VERSION_OFFSET)
+#ifndef __ASSEMBLY__
+/* SSC_VERSION related accessors */
+/* Returns the part number of the platform */
+#define GET_SGI_PART_NUM                                       \
+		GET_SSC_VERSION_PART_NUM(mmio_read_32(SSC_VERSION))
+/* Returns the configuration number of the platform */
+#define GET_SGI_CONFIG_NUM                                     \
+		GET_SSC_VERSION_CONFIG(mmio_read_32(SSC_VERSION))
+#endif /* __ASSEMBLY__ */
+
+#endif /* __PLATFORM_DEF_H__ */
diff --git a/plat/arm/css/sgi/include/sgi_plat_config.h b/plat/arm/css/sgi/include/sgi_plat_config.h
new file mode 100644
index 0000000..c9ff1fe
--- /dev/null
+++ b/plat/arm/css/sgi/include/sgi_plat_config.h
@@ -0,0 +1,44 @@
+/*
+ * Copyright (c) 2018, ARM Limited and Contributors. All rights reserved.
+ *
+ * SPDX-License-Identifier: BSD-3-Clause
+ */
+
+#ifndef __SGI_PLAT_CONFIG_H__
+#define __SGI_PLAT_CONFIG_H__
+
+#include <arm_gic.h>
+#include <ccn.h>
+#include <gicv3.h>
+
+/* The type of interconnect */
+typedef enum {
+	ARM_CCI = 0,
+	ARM_CCN,
+	ARM_CMN
+} css_inteconn_type_t;
+
+typedef ccn_desc_t inteconn_desc_t;
+
+/* Interconnect configurations */
+typedef struct css_inteconn_config {
+	css_inteconn_type_t ip_type;
+	const inteconn_desc_t *plat_inteconn_desc;
+} css_inteconn_config_t;
+
+/* Topology configurations */
+typedef struct css_topology {
+	const unsigned char *power_tree;
+	unsigned int plat_cluster_core_count;
+} css_topology_t;
+
+typedef struct css_plat_config {
+	const gicv3_driver_data_t *gic_data;
+	const css_inteconn_config_t *inteconn;
+	const css_topology_t *topology;
+} css_plat_config_t;
+
+void plat_config_init(void);
+css_plat_config_t *get_plat_config(void);
+
+#endif /* __SGI_PLAT_CONFIG_H__ */
diff --git a/plat/arm/css/sgi/include/sgi_variant.h b/plat/arm/css/sgi/include/sgi_variant.h
new file mode 100644
index 0000000..5698d0a
--- /dev/null
+++ b/plat/arm/css/sgi/include/sgi_variant.h
@@ -0,0 +1,13 @@
+/*
+ * Copyright (c) 2018, ARM Limited and Contributors. All rights reserved.
+ *
+ * SPDX-License-Identifier: BSD-3-Clause
+ */
+
+#ifndef __SGI_VARIANT_H__
+#define __SGI_VARIANT_H__
+
+/* SSC_VERSION values for SGI575 */
+#define SGI575_SSC_VER_PART_NUM		0x0783
+
+#endif /* __SGI_VARIANT_H__ */
diff --git a/plat/arm/css/sgi/sgi-common.mk b/plat/arm/css/sgi/sgi-common.mk
new file mode 100644
index 0000000..9c398b7
--- /dev/null
+++ b/plat/arm/css/sgi/sgi-common.mk
@@ -0,0 +1,59 @@
+#
+# Copyright (c) 2018, ARM Limited and Contributors. All rights reserved.
+#
+# SPDX-License-Identifier: BSD-3-Clause
+#
+
+ENABLE_PLAT_COMPAT		:=	0
+
+CSS_ENT_BASE			:=	plat/arm/css/sgi
+
+INTERCONNECT_SOURCES	:=	${CSS_ENT_BASE}/sgi_interconnect.c
+
+PLAT_INCLUDES		+=	-I${CSS_ENT_BASE}/include
+
+ENT_CPU_SOURCES		:=	lib/cpus/aarch64/cortex_a75.S
+
+ENT_GIC_SOURCES		:=	drivers/arm/gic/common/gic_common.c	\
+				drivers/arm/gic/v3/gicv3_main.c		\
+				drivers/arm/gic/v3/gicv3_helpers.c	\
+				plat/common/plat_gicv3.c		\
+				plat/arm/common/arm_gicv3.c		\
+				${CSS_ENT_BASE}/sgi_gic_config.c	\
+				drivers/arm/gic/v3/gic600.c
+
+
+PLAT_BL_COMMON_SOURCES	+=	${CSS_ENT_BASE}/sgi_plat.c	\
+				${CSS_ENT_BASE}/aarch64/sgi_helper.S
+
+BL1_SOURCES		+=	${INTERCONNECT_SOURCES}			\
+				${ENT_CPU_SOURCES}			\
+				${CSS_ENT_BASE}/sgi_bl1_setup.c	\
+				${CSS_ENT_BASE}/sgi_plat_config.c
+
+BL2_SOURCES		+=	${CSS_ENT_BASE}/sgi_security.c
+
+BL31_SOURCES		+=	${ENT_CPU_SOURCES}			\
+				${INTERCONNECT_SOURCES}			\
+				${ENT_GIC_SOURCES}			\
+				${CSS_ENT_BASE}/sgi_bl31_setup.c	\
+				${CSS_ENT_BASE}/sgi_topology.c	\
+				${CSS_ENT_BASE}/sgi_plat_config.c
+
+$(eval $(call add_define,SGI_PLAT))
+
+override CSS_LOAD_SCP_IMAGES	:=	0
+override NEED_BL2U		:=	no
+override ARM_BL31_IN_DRAM	:=	1
+
+# System coherency is managed in hardware
+HW_ASSISTED_COHERENCY	:=	1
+
+# When building for systems with hardware-assisted coherency, there's no need to
+# use USE_COHERENT_MEM. Require that USE_COHERENT_MEM must be set to 0 too.
+USE_COHERENT_MEM	:=	0
+
+include plat/arm/common/arm_common.mk
+include plat/arm/css/common/css_common.mk
+include plat/arm/soc/common/soc_css.mk
+include plat/arm/board/common/board_common.mk
diff --git a/plat/arm/css/sgi/sgi_bl1_setup.c b/plat/arm/css/sgi/sgi_bl1_setup.c
new file mode 100644
index 0000000..d3d98d9
--- /dev/null
+++ b/plat/arm/css/sgi/sgi_bl1_setup.c
@@ -0,0 +1,19 @@
+/*
+ * Copyright (c) 2018, ARM Limited and Contributors. All rights reserved.
+ *
+ * SPDX-License-Identifier: BSD-3-Clause
+ */
+
+#include <bl_common.h>
+#include <debug.h>
+#include <plat_arm.h>
+#include <sgi_plat_config.h>
+#include <soc_css.h>
+
+void bl1_early_platform_setup(void)
+{
+	/* Initialize the platform configuration structure */
+	plat_config_init();
+
+	arm_bl1_early_platform_setup();
+}
diff --git a/plat/arm/css/sgi/sgi_bl31_setup.c b/plat/arm/css/sgi/sgi_bl31_setup.c
new file mode 100644
index 0000000..0928b83
--- /dev/null
+++ b/plat/arm/css/sgi/sgi_bl31_setup.c
@@ -0,0 +1,34 @@
+/*
+ * Copyright (c) 2018, ARM Limited and Contributors. All rights reserved.
+ *
+ * SPDX-License-Identifier: BSD-3-Clause
+ */
+
+#include <bl_common.h>
+#include <debug.h>
+#include <plat_arm.h>
+#include <sgi_plat_config.h>
+
+void bl31_early_platform_setup2(u_register_t arg0, u_register_t arg1,
+				u_register_t arg2, u_register_t arg3)
+{
+	uint32_t plat_version;
+	bl_params_node_t *bl_params;
+
+	bl_params = ((bl_params_t *)arg0)->head;
+
+	/* Initialize the platform configuration structure */
+	plat_config_init();
+
+	while (bl_params) {
+		if (bl_params->image_id == BL33_IMAGE_ID) {
+			plat_version = mmio_read_32(SSC_VERSION);
+			bl_params->ep_info->args.arg2 = plat_version;
+			break;
+		}
+
+		bl_params = bl_params->next_params_info;
+	}
+
+	arm_bl31_early_platform_setup((void *)arg0, arg1, arg2, (void *)arg3);
+}
diff --git a/plat/arm/css/sgi/sgi_gic_config.c b/plat/arm/css/sgi/sgi_gic_config.c
new file mode 100644
index 0000000..dfccc1b
--- /dev/null
+++ b/plat/arm/css/sgi/sgi_gic_config.c
@@ -0,0 +1,18 @@
+/*
+ * Copyright (c) 2018, ARM Limited and Contributors. All rights reserved.
+ *
+ * SPDX-License-Identifier: BSD-3-Clause
+ */
+
+#include <sgi_plat_config.h>
+
+void plat_arm_gic_driver_init(void)
+{
+	/*
+	 * The GICv3 driver is initialized in EL3 and does not need
+	 * to be initialized again in S-EL1. This is because the S-EL1
+	 * can use GIC system registers to manage interrupts and does
+	 * not need GIC interface base addresses to be configured.
+	 */
+	gicv3_driver_init(get_plat_config()->gic_data);
+}
diff --git a/plat/arm/css/sgi/sgi_interconnect.c b/plat/arm/css/sgi/sgi_interconnect.c
new file mode 100644
index 0000000..f4e7676
--- /dev/null
+++ b/plat/arm/css/sgi/sgi_interconnect.c
@@ -0,0 +1,36 @@
+/*
+ * Copyright (c) 2018, ARM Limited and Contributors. All rights reserved.
+ *
+ * SPDX-License-Identifier: BSD-3-Clause
+ */
+
+#include <arch_helpers.h>
+#include <debug.h>
+#include <sgi_plat_config.h>
+
+/*
+ * For SGI575 which support FCM (with automatic interconnect enter/exit),
+ * we should not do anything in these interface functions.
+ * They are used to override the weak functions in cci drivers.
+ */
+
+/******************************************************************************
+ * Helper function to initialize ARM interconnect driver.
+ *****************************************************************************/
+void plat_arm_interconnect_init(void)
+{
+}
+
+/******************************************************************************
+ * Helper function to place current master into coherency
+ *****************************************************************************/
+void plat_arm_interconnect_enter_coherency(void)
+{
+}
+
+/******************************************************************************
+ * Helper function to remove current master from coherency
+ *****************************************************************************/
+void plat_arm_interconnect_exit_coherency(void)
+{
+}
diff --git a/plat/arm/css/sgi/sgi_plat.c b/plat/arm/css/sgi/sgi_plat.c
new file mode 100644
index 0000000..94d713d
--- /dev/null
+++ b/plat/arm/css/sgi/sgi_plat.c
@@ -0,0 +1,121 @@
+/*
+ * Copyright (c) 2018, ARM Limited and Contributors. All rights reserved.
+ *
+ * SPDX-License-Identifier: BSD-3-Clause
+ */
+
+#include <arm_def.h>
+#include <bl_common.h>
+#include <ccn.h>
+#include <debug.h>
+#include <plat_arm.h>
+#include <platform.h>
+#include "../../../../bl1/bl1_private.h"
+
+#if USE_COHERENT_MEM
+/*
+ * The next 2 constants identify the extents of the coherent memory region.
+ * These addresses are used by the MMU setup code and therefore they must be
+ * page-aligned.  It is the responsibility of the linker script to ensure that
+ * __COHERENT_RAM_START__ and __COHERENT_RAM_END__ linker symbols
+ * refer to page-aligned addresses.
+ */
+#define BL1_COHERENT_RAM_BASE (unsigned long)(&__COHERENT_RAM_START__)
+#define BL1_COHERENT_RAM_LIMIT (unsigned long)(&__COHERENT_RAM_END__)
+#define BL2_COHERENT_RAM_BASE (unsigned long)(&__COHERENT_RAM_START__)
+#define BL2_COHERENT_RAM_LIMIT (unsigned long)(&__COHERENT_RAM_END__)
+
+#define BL31_COHERENT_RAM_BASE (uintptr_t)(&__COHERENT_RAM_START__)
+#define BL31_COHERENT_RAM_LIMIT (uintptr_t)(&__COHERENT_RAM_END__)
+#endif
+
+#define SGI_MAP_FLASH0_RO	MAP_REGION_FLAT(V2M_FLASH0_BASE,\
+						V2M_FLASH0_SIZE,	\
+						MT_DEVICE | MT_RO | MT_SECURE)
+/*
+ * Table of regions for different BL stages to map using the MMU.
+ * This doesn't include Trusted RAM as the 'mem_layout' argument passed to
+ * arm_configure_mmu_elx() will give the available subset of that.
+ *
+ * Replace or extend the below regions as required
+ */
+#if IMAGE_BL1
+const mmap_region_t plat_arm_mmap[] = {
+	ARM_MAP_SHARED_RAM,
+	SGI_MAP_FLASH0_RO,
+	CSS_SGI_MAP_DEVICE,
+	SOC_CSS_MAP_DEVICE,
+	{0}
+};
+#endif
+#if IMAGE_BL2
+const mmap_region_t plat_arm_mmap[] = {
+	ARM_MAP_SHARED_RAM,
+	SGI_MAP_FLASH0_RO,
+	CSS_SGI_MAP_DEVICE,
+	SOC_CSS_MAP_DEVICE,
+	ARM_MAP_NS_DRAM1,
+#if ARM_BL31_IN_DRAM
+	ARM_MAP_BL31_SEC_DRAM,
+#endif
+	{0}
+};
+#endif
+#if IMAGE_BL31
+const mmap_region_t plat_arm_mmap[] = {
+	ARM_MAP_SHARED_RAM,
+	V2M_MAP_IOFPGA,
+	CSS_SGI_MAP_DEVICE,
+	SOC_CSS_MAP_DEVICE,
+	{0}
+};
+#endif
+
+ARM_CASSERT_MMAP
+
+/*
+ * Set up the page tables for the generic and platform-specific memory regions.
+ * The extents of the generic memory regions are specified by the function
+ * arguments and consist of:
+ * - Trusted SRAM seen by the BL image;
+ * - Code section;
+ * - Read-only data section;
+ * - Coherent memory region, if applicable.
+ */
+
+#if IMAGE_BL1
+void bl1_plat_arch_setup(void)
+{
+	arm_setup_page_tables(ARM_BL_RAM_BASE,
+			      ARM_BL_RAM_SIZE,
+			      BL_CODE_BASE,
+			      BL1_CODE_END,
+			      BL1_RO_DATA_BASE,
+			      BL1_RO_DATA_END
+#if USE_COHERENT_MEM
+			      , BL1_COHERENT_RAM_BASE,
+			      BL1_COHERENT_RAM_LIMIT
+#endif /* USE_COHERENT_MEM */
+			     );
+
+	enable_mmu_el3(0);
+}
+#endif /* IMAGE_BL1 */
+
+#if IMAGE_BL2
+void bl2_plat_arch_setup(void)
+{
+	arm_setup_page_tables(BL2_BASE,
+			      BL2_LIMIT-BL2_BASE,
+			      BL_CODE_BASE,
+			      BL_CODE_END,
+			      BL_RO_DATA_BASE,
+			      BL_RO_DATA_END
+#if USE_COHERENT_MEM
+			      , BL2_COHERENT_RAM_BASE,
+			      BL2_COHERENT_RAM_LIMIT
+#endif /* USE_COHERENT_MEM */
+			      );
+	enable_mmu_el1(0);
+}
+#endif /* IMAGE_BL2 */
diff --git a/plat/arm/css/sgi/sgi_plat_config.c b/plat/arm/css/sgi/sgi_plat_config.c
new file mode 100644
index 0000000..96d31e2
--- /dev/null
+++ b/plat/arm/css/sgi/sgi_plat_config.c
@@ -0,0 +1,73 @@
+/*
+ * Copyright (c) 2018, ARM Limited and Contributors. All rights reserved.
+ *
+ * SPDX-License-Identifier: BSD-3-Clause
+ */
+
+#include <assert.h>
+#include <debug.h>
+#include <plat_arm.h>
+#include <platform_def.h>
+#include <sgi_variant.h>
+#include <sgi_plat_config.h>
+#include <string.h>
+
+static css_plat_config_t *css_plat_info;
+
+/* GIC */
+/* The GICv3 driver only needs to be initialized in EL3 */
+uintptr_t rdistif_base_addrs[PLATFORM_CORE_COUNT];
+
+const interrupt_prop_t sgi575_interrupt_props[] = {
+	CSS_G1S_IRQ_PROPS(INTR_GROUP1S),
+	ARM_G0_IRQ_PROPS(INTR_GROUP0),
+};
+
+/* Special definition for SGI575 */
+/* GIC configuration for SGI575 */
+const gicv3_driver_data_t sgi575_gic_data = {
+		.gicd_base = PLAT_ARM_GICD_BASE,
+		.gicr_base = PLAT_ARM_GICR_BASE,
+		.interrupt_props = sgi575_interrupt_props,
+		.interrupt_props_num = ARRAY_SIZE(sgi575_interrupt_props),
+		.rdistif_num = PLATFORM_CORE_COUNT,
+		.rdistif_base_addrs = rdistif_base_addrs,
+		.mpidr_to_core_pos = plat_arm_calc_core_pos
+		};
+
+/* Interconnect configuration for SGI575 */
+const css_inteconn_config_t sgi575_inteconn = {
+	.ip_type = ARM_CMN,
+	.plat_inteconn_desc = NULL
+};
+
+/* Configuration structure for SGI575 */
+css_plat_config_t sgi575_config = {
+	.gic_data = &sgi575_gic_data,
+	.inteconn = &sgi575_inteconn,
+};
+
+/*******************************************************************************
+ * This function initializes the platform sturcture.
+ ******************************************************************************/
+void plat_config_init(void)
+{
+	/* Get the platform configurations */
+	switch (GET_SGI_PART_NUM) {
+	case SGI575_SSC_VER_PART_NUM:
+		css_plat_info = &sgi575_config;
+		break;
+	default:
+		ERROR("Not a valid sgi variant!\n");
+		panic();
+	}
+}
+
+/*******************************************************************************
+ * This function returns the platform structure pointer.
+ ******************************************************************************/
+css_plat_config_t *get_plat_config(void)
+{
+	assert(css_plat_info != NULL);
+	return css_plat_info;
+}
diff --git a/plat/arm/css/sgi/sgi_security.c b/plat/arm/css/sgi/sgi_security.c
new file mode 100644
index 0000000..23e1a64
--- /dev/null
+++ b/plat/arm/css/sgi/sgi_security.c
@@ -0,0 +1,15 @@
+/*
+ * Copyright (c) 2018, ARM Limited and Contributors. All rights reserved.
+ *
+ * SPDX-License-Identifier: BSD-3-Clause
+ */
+
+#include <arm_config.h>
+#include <plat_arm.h>
+
+/*
+ * We assume that all security programming is done by the primary core.
+ */
+void plat_arm_security_setup(void)
+{
+}
diff --git a/plat/arm/css/sgi/sgi_topology.c b/plat/arm/css/sgi/sgi_topology.c
new file mode 100644
index 0000000..2136591
--- /dev/null
+++ b/plat/arm/css/sgi/sgi_topology.c
@@ -0,0 +1,44 @@
+/*
+ * Copyright (c) 2018, ARM Limited and Contributors. All rights reserved.
+ *
+ * SPDX-License-Identifier: BSD-3-Clause
+ */
+
+#include <plat_arm.h>
+#include <sgi_plat_config.h>
+
+/* Topology */
+/*
+ * The power domain tree descriptor. The cluster power domains are
+ * arranged so that when the PSCI generic code creates the power domain tree,
+ * the indices of the CPU power domain nodes it allocates match the linear
+ * indices returned by plat_core_pos_by_mpidr().
+ */
+const unsigned char sgi_pd_tree_desc[] = {
+	PLAT_ARM_CLUSTER_COUNT,
+	CSS_SGI_MAX_CORES_PER_CLUSTER,
+	CSS_SGI_MAX_CORES_PER_CLUSTER
+};
+
+/* Topology configuration for sgi platform */
+const css_topology_t sgi_topology = {
+	.power_tree = sgi_pd_tree_desc,
+	.plat_cluster_core_count = CSS_SGI_MAX_CORES_PER_CLUSTER
+};
+
+/*******************************************************************************
+ * This function returns the topology tree information.
+ ******************************************************************************/
+const unsigned char *plat_get_power_domain_tree_desc(void)
+{
+	return sgi_topology.power_tree;
+}
+
+/*******************************************************************************
+ * This function returns the core count within the cluster corresponding to
+ * `mpidr`.
+ ******************************************************************************/
+unsigned int plat_arm_get_cluster_core_count(u_register_t mpidr)
+{
+	return sgi_topology.plat_cluster_core_count;
+}