feat(rdn2): add board support for rdn2cfg2 variant

Add board support for variant 2 of RD-N2 platform which is a four chip
variant with 4 cores on each chip. The "CSS_SGI_PLATFORM_VARIANT" value
is 2 for multi-chip variant. The "CSS_SGI_CHIP_COUNT_MACRO" can be in
the range [1, 4] for multi-chip variant.

Signed-off-by: Aditya Angadi <aditya.angadi@arm.com>
Change-Id: I6412106e80e2f17704c796226c2ee9fe808705ba
diff --git a/plat/arm/board/rdn2/rdn2_plat.c b/plat/arm/board/rdn2/rdn2_plat.c
index 5bf14e3..8cf1929 100644
--- a/plat/arm/board/rdn2/rdn2_plat.c
+++ b/plat/arm/board/rdn2/rdn2_plat.c
@@ -1,12 +1,87 @@
 /*
- * Copyright (c) 2020, ARM Limited and Contributors. All rights reserved.
+ * Copyright (c) 2020-2021, ARM Limited and Contributors. All rights reserved.
  *
  * SPDX-License-Identifier: BSD-3-Clause
  */
 
+#include <common/debug.h>
+#include <drivers/arm/gic600_multichip.h>
+#include <plat/arm/common/plat_arm.h>
 #include <plat/common/platform.h>
+#include <sgi_soc_platform_def_v2.h>
 #include <sgi_plat.h>
 
+#if defined(IMAGE_BL31)
+#if (CSS_SGI_PLATFORM_VARIANT == 2)
+static const mmap_region_t rdn2mc_dynamic_mmap[] = {
+#if CSS_SGI_CHIP_COUNT > 1
+	ARM_MAP_SHARED_RAM_REMOTE_CHIP(1),
+	CSS_SGI_MAP_DEVICE_REMOTE_CHIP(1),
+#endif
+#if CSS_SGI_CHIP_COUNT > 2
+	ARM_MAP_SHARED_RAM_REMOTE_CHIP(2),
+	CSS_SGI_MAP_DEVICE_REMOTE_CHIP(2),
+#endif
+#if CSS_SGI_CHIP_COUNT > 3
+	ARM_MAP_SHARED_RAM_REMOTE_CHIP(3),
+	CSS_SGI_MAP_DEVICE_REMOTE_CHIP(3),
+#endif
+};
+#endif
+
+#if (CSS_SGI_PLATFORM_VARIANT == 2)
+static struct gic600_multichip_data rdn2mc_multichip_data __init = {
+	.rt_owner_base = PLAT_ARM_GICD_BASE,
+	.rt_owner = 0,
+	.chip_count = CSS_SGI_CHIP_COUNT,
+	.chip_addrs = {
+		PLAT_ARM_GICD_BASE >> 16,
+#if CSS_SGI_CHIP_COUNT > 1
+		(PLAT_ARM_GICD_BASE + CSS_SGI_REMOTE_CHIP_MEM_OFFSET(1)) >> 16,
+#endif
+#if CSS_SGI_CHIP_COUNT > 2
+		(PLAT_ARM_GICD_BASE + CSS_SGI_REMOTE_CHIP_MEM_OFFSET(2)) >> 16,
+#endif
+#if CSS_SGI_CHIP_COUNT > 3
+		(PLAT_ARM_GICD_BASE + CSS_SGI_REMOTE_CHIP_MEM_OFFSET(3)) >> 16,
+#endif
+	},
+	.spi_ids = {
+		{32, 479},
+	#if CSS_SGI_CHIP_COUNT > 1
+		{0, 0},
+	#endif
+	#if CSS_SGI_CHIP_COUNT > 2
+		{0, 0},
+	#endif
+	#if CSS_SGI_CHIP_COUNT > 3
+		{0, 0},
+	#endif
+	}
+};
+#endif
+
+#if (CSS_SGI_PLATFORM_VARIANT == 2)
+static uintptr_t rdn2mc_multichip_gicr_frames[] = {
+	/* Chip 0's GICR Base */
+	PLAT_ARM_GICR_BASE,
+#if CSS_SGI_CHIP_COUNT > 1
+	/* Chip 1's GICR BASE */
+	PLAT_ARM_GICR_BASE + CSS_SGI_REMOTE_CHIP_MEM_OFFSET(1),
+#endif
+#if CSS_SGI_CHIP_COUNT > 2
+	/* Chip 2's GICR BASE */
+	PLAT_ARM_GICR_BASE + CSS_SGI_REMOTE_CHIP_MEM_OFFSET(2),
+#endif
+#if CSS_SGI_CHIP_COUNT > 3
+	/* Chip 3's GICR BASE */
+	PLAT_ARM_GICR_BASE + CSS_SGI_REMOTE_CHIP_MEM_OFFSET(3),
+#endif
+	UL(0)	/* Zero Termination */
+};
+#endif
+#endif /* IMAGE_BL31 */
+
 unsigned int plat_arm_sgi_get_platform_id(void)
 {
 	return mmio_read_32(SID_REG_BASE + SID_SYSTEM_ID_OFFSET)
@@ -25,7 +100,39 @@
 			     SID_MULTI_CHIP_MODE_SHIFT;
 }
 
+#if defined(IMAGE_BL31)
 void bl31_platform_setup(void)
 {
+#if (CSS_SGI_PLATFORM_VARIANT == 2)
+	int ret;
+	unsigned int i;
+
+	if (plat_arm_sgi_get_multi_chip_mode() == 0) {
+		ERROR("Chip Count is set to %u but multi-chip mode is not "
+			"enabled\n", CSS_SGI_CHIP_COUNT);
+		panic();
+	} else {
+		INFO("Enabling multi-chip support for RD-N2 variant\n");
+
+		for (i = 0; i < ARRAY_SIZE(rdn2mc_dynamic_mmap); i++) {
+			ret = mmap_add_dynamic_region(
+					rdn2mc_dynamic_mmap[i].base_pa,
+					rdn2mc_dynamic_mmap[i].base_va,
+					rdn2mc_dynamic_mmap[i].size,
+					rdn2mc_dynamic_mmap[i].attr);
+			if (ret != 0) {
+				ERROR("Failed to add dynamic mmap entry for"
+					" i: %d " "(ret=%d)\n", i, ret);
+				panic();
+			}
+		}
+
+		plat_arm_override_gicr_frames(
+			rdn2mc_multichip_gicr_frames);
+		gic600_multichip_init(&rdn2mc_multichip_data);
+	}
+#endif
+
 	sgi_bl31_common_platform_setup();
 }
+#endif /* IMAGE_BL31 */