Merge changes from topic "rdn1edge_dual" into integration

* changes:
  board/rde1edge: fix incorrect topology tree description
  plat/arm/sgi: introduce number of chips macro

docs/plat/arm/arm-build-options.rst

@@ -114,6 +114,11 @@ Arm CSS Platform-Specific Build Options
    management operations and for SCP RAM Firmware transfer. If this option
    is set to 1, then SCMI/SDS drivers will be used. Default is 0.
 
+ - ``CSS_SGI_CHIP_COUNT``: Configures the number of chips on a SGI/RD platform
+   which supports multi-chip operation. If ``CSS_SGI_CHIP_COUNT`` is set to any
+   valid value greater than 1, the platform code performs required configuration
+   to support multi-chip operation.
+
 --------------
 
 *Copyright (c) 2019-2020, Arm Limited. All rights reserved.*

plat/arm/board/rde1edge/platform.mk

@@ -47,4 +47,9 @@ NT_FW_CONFIG		:=	${BUILD_PLAT}/fdts/${PLAT}_nt_fw_config.dtb
 # Add the NT_FW_CONFIG to FIP and specify the same to certtool
 $(eval $(call TOOL_ADD_PAYLOAD,${NT_FW_CONFIG},--nt-fw-config))
 
+ifneq ($(CSS_SGI_CHIP_COUNT),1)
+ $(error  "Chip count for RDE1Edge should be 1, currently set to \
+   ${CSS_SGI_CHIP_COUNT}.")
+endif
+
 override CTX_INCLUDE_AARCH32_REGS	:= 0

plat/arm/board/rde1edge/rde1edge_topology.c

@@ -7,12 +7,15 @@
 #include <plat/arm/common/plat_arm.h>
 
 /******************************************************************************
- * The power domain tree descriptor.
+ * The power domain tree descriptor. RD-E1-Edge platform consists of two
+ * clusters with eight CPUs in each cluster. The CPUs are multi-threaded with
+ * two threads per CPU.
  ******************************************************************************/
 static const unsigned char rde1edge_pd_tree_desc[] = {
+	CSS_SGI_CHIP_COUNT,
 	PLAT_ARM_CLUSTER_COUNT,
-	CSS_SGI_MAX_CPUS_PER_CLUSTER,
-	CSS_SGI_MAX_CPUS_PER_CLUSTER
+	CSS_SGI_MAX_CPUS_PER_CLUSTER * CSS_SGI_MAX_PE_PER_CPU,
+	CSS_SGI_MAX_CPUS_PER_CLUSTER * CSS_SGI_MAX_PE_PER_CPU
 };
 
 /******************************************************************************

plat/arm/board/rdn1edge/platform.mk

@@ -47,4 +47,9 @@ NT_FW_CONFIG		:=	${BUILD_PLAT}/fdts/${PLAT}_nt_fw_config.dtb
 # Add the NT_FW_CONFIG to FIP and specify the same to certtool
 $(eval $(call TOOL_ADD_PAYLOAD,${NT_FW_CONFIG},--nt-fw-config))
 
+ifneq ($(CSS_SGI_CHIP_COUNT),1)
+ $(error  "Chip count for RDN1Edge should be 1, currently set to \
+   ${CSS_SGI_CHIP_COUNT}.")
+endif
+
 override CTX_INCLUDE_AARCH32_REGS	:= 0

plat/arm/board/sgi575/platform.mk

@@ -46,3 +46,8 @@ NT_FW_CONFIG		:=	${BUILD_PLAT}/fdts/${PLAT}_nt_fw_config.dtb
 
 # Add the NT_FW_CONFIG to FIP and specify the same to certtool
 $(eval $(call TOOL_ADD_PAYLOAD,${NT_FW_CONFIG},--nt-fw-config))
+
+ifneq ($(CSS_SGI_CHIP_COUNT),1)
+ $(error  "Chip count for SGI575 should be 1, currently set to \
+   ${CSS_SGI_CHIP_COUNT}.")
+endif

plat/arm/css/sgi/sgi-common.mk

@@ -16,6 +16,8 @@ EL3_EXCEPTION_HANDLING		:=	0
 
 HANDLE_EA_EL3_FIRST		:=	0
 
+CSS_SGI_CHIP_COUNT		:=	1
+
 INTERCONNECT_SOURCES	:=	${CSS_ENT_BASE}/sgi_interconnect.c
 
 PLAT_INCLUDES		+=	-I${CSS_ENT_BASE}/include
@@ -52,6 +54,8 @@ endif
 
 $(eval $(call add_define,SGI_PLAT))
 
+$(eval $(call add_define,CSS_SGI_CHIP_COUNT))
+
 override CSS_LOAD_SCP_IMAGES	:=	0
 override NEED_BL2U		:=	no
 override ARM_BL31_IN_DRAM	:=	1