board/rdn1edge: add support for dual-chip configuration

RD-N1-Edge based platforms can operate in dual-chip configuration
wherein two rdn1edge SoCs are connected through a high speed coherent
CCIX link.

This patch adds a function to check if the RD-N1-Edge platform is
operating in multi-chip mode by reading the SID register's NODE_ID
value. If operating in multi-chip mode, initialize GIC-600 multi-chip
operation by overriding the default GICR frames with array of GICR
frames and setting the chip 0 as routing table owner.

The address space of the second RD-N1-Edge chip (chip 1) starts from the
address 4TB. So increase the physical and virtual address space size to
43 bits to accommodate the multi-chip configuration. If the multi-chip
mode configuration is detected, dynamically add mmap entry for the
peripherals memory region of the second RD-N1-Edge SoC. This is required
to let the BL31 platform setup stage to configure the devices in the
second chip.

PLATFORM_CORE_COUNT macro is set to be multiple of CSS_SGI_CHIP_COUNT
and topology changes are added to represent the dual-chip configuration.

In order the build the dual-chip platform, CSS_SGI_CHIP_COUNT macro
should be set to 2:
export CROSS_COMPILE=<path-to-cross-compiler>
make PLAT=rdn1edge CSS_SGI_CHIP_COUNT=2 ARCH=aarch64 all

Change-Id: I576cdaf71f0b0e41b9a9181fa4feb7091f8c7bb4
Signed-off-by: Aditya Angadi <aditya.angadi@arm.com>
Signed-off-by: Vijayenthiran Subramaniam <vijayenthiran.subramaniam@arm.com>
diff --git a/plat/arm/board/rdn1edge/rdn1edge_plat.c b/plat/arm/board/rdn1edge/rdn1edge_plat.c
index f7c7e9b..f62c6f4 100644
--- a/plat/arm/board/rdn1edge/rdn1edge_plat.c
+++ b/plat/arm/board/rdn1edge/rdn1edge_plat.c
@@ -4,9 +4,42 @@
  * 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_base_platform_def.h>
 #include <sgi_plat.h>
 
+#if defined(IMAGE_BL31)
+static const mmap_region_t rdn1edge_dynamic_mmap[] = {
+	ARM_MAP_SHARED_RAM_REMOTE_CHIP(1),
+	CSS_SGI_MAP_DEVICE_REMOTE_CHIP(1),
+	SOC_CSS_MAP_DEVICE_REMOTE_CHIP(1)
+};
+
+static struct gic600_multichip_data rdn1e1_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,
+		(PLAT_ARM_GICD_BASE + CSS_SGI_REMOTE_CHIP_MEM_OFFSET(1)) >> 16
+	},
+	.spi_ids = {
+		{32, 255},
+		{0, 0}
+	}
+};
+
+static uintptr_t rdn1e1_multichip_gicr_frames[] = {
+	PLAT_ARM_GICR_BASE,				/* Chip 0's GICR Base */
+	PLAT_ARM_GICR_BASE +
+		CSS_SGI_REMOTE_CHIP_MEM_OFFSET(1),	/* Chip 1's GICR BASE */
+	UL(0)						/* Zero Termination */
+};
+#endif /* IMAGE_BL31 */
+
 unsigned int plat_arm_sgi_get_platform_id(void)
 {
 	return mmio_read_32(SID_REG_BASE + SID_SYSTEM_ID_OFFSET)
@@ -24,7 +57,41 @@
 			SID_MULTI_CHIP_MODE_MASK) >> SID_MULTI_CHIP_MODE_SHIFT;
 }
 
+/*
+ * IMAGE_BL31 macro is added to build bl31_platform_setup function only for BL31
+ * because PLAT_XLAT_TABLES_DYNAMIC macro is set to build only for BL31 and not
+ * for other stages.
+ */
+#if defined(IMAGE_BL31)
 void bl31_platform_setup(void)
 {
+	int i, ret;
+
+	if (plat_arm_sgi_get_multi_chip_mode() == 0 && CSS_SGI_CHIP_COUNT > 1) {
+		ERROR("Chip Count is set to %d but multi-chip mode not enabled\n",
+				CSS_SGI_CHIP_COUNT);
+		panic();
+	} else if (plat_arm_sgi_get_multi_chip_mode() == 1 &&
+			CSS_SGI_CHIP_COUNT > 1) {
+		INFO("Enabling support for multi-chip in RD-N1-Edge\n");
+
+		for (i = 0; i < ARRAY_SIZE(rdn1edge_dynamic_mmap); i++) {
+			ret = mmap_add_dynamic_region(
+					rdn1edge_dynamic_mmap[i].base_pa,
+					rdn1edge_dynamic_mmap[i].base_va,
+					rdn1edge_dynamic_mmap[i].size,
+					rdn1edge_dynamic_mmap[i].attr
+					);
+			if (ret != 0) {
+				ERROR("Failed to add dynamic mmap entry\n");
+				panic();
+			}
+		}
+
+		plat_arm_override_gicr_frames(rdn1e1_multichip_gicr_frames);
+		gic600_multichip_init(&rdn1e1_multichip_data);
+	}
+
 	sgi_bl31_common_platform_setup();
 }
+#endif /* IMAGE_BL31 */