plat/arm/sgi: add platform support for SGI-Clark.Helios platform

SGI-Clark.Helios platform is based on multi-threaded CPUs and uses an
additional thread power domain level as well.

Define a power domain tree descriptor 'sgi_clark_helios_pd_tree_desc'
for SGI-Clark.Helios platform and let the function
'plat_get_power_domain_tree_desc' pick up the correct power
domain tree descriptor based on the platform.

Change-Id: Ibc6d551b570bc740053316a3608c455679d9155b
Signed-off-by: Chandni Cherukuri <chandni.cherukuri@arm.com>

plat/arm/css/sgi/include/sgi_variant.h

@@ -12,6 +12,7 @@
 
 /* SID Version values for SGI-Clark */
 #define SGI_CLARK_SID_VER_PART_NUM		0x0786
+#define SGI_CLARK_HELIOS_CONFIG_ID		0x2
 
 /* Structure containing SGI platform variant information */
 typedef struct sgi_platform_info {

plat/arm/css/sgi/sgi_topology.c

@@ -5,6 +5,7 @@
  */
 
 #include <plat_arm.h>
+#include <sgi_variant.h>
 
 /* Topology */
 /*
@@ -19,11 +20,38 @@ const unsigned char sgi_pd_tree_desc[] = {
 	CSS_SGI_MAX_CPUS_PER_CLUSTER
 };
 
+/* SGI-Clark.Helios platform consists of 16 physical CPUS and 32 threads */
+const unsigned char sgi_clark_helios_pd_tree_desc[] = {
+	PLAT_ARM_CLUSTER_COUNT,
+	CSS_SGI_MAX_CPUS_PER_CLUSTER,
+	CSS_SGI_MAX_CPUS_PER_CLUSTER,
+	CSS_SGI_MAX_PE_PER_CPU,
+	CSS_SGI_MAX_PE_PER_CPU,
+	CSS_SGI_MAX_PE_PER_CPU,
+	CSS_SGI_MAX_PE_PER_CPU,
+	CSS_SGI_MAX_PE_PER_CPU,
+	CSS_SGI_MAX_PE_PER_CPU,
+	CSS_SGI_MAX_PE_PER_CPU,
+	CSS_SGI_MAX_PE_PER_CPU,
+	CSS_SGI_MAX_PE_PER_CPU,
+	CSS_SGI_MAX_PE_PER_CPU,
+	CSS_SGI_MAX_PE_PER_CPU,
+	CSS_SGI_MAX_PE_PER_CPU,
+	CSS_SGI_MAX_PE_PER_CPU,
+	CSS_SGI_MAX_PE_PER_CPU,
+	CSS_SGI_MAX_PE_PER_CPU,
+	CSS_SGI_MAX_PE_PER_CPU
+};
+
 /*******************************************************************************
  * This function returns the topology tree information.
  ******************************************************************************/
 const unsigned char *plat_get_power_domain_tree_desc(void)
 {
+	if (sgi_plat_info.platform_id == SGI_CLARK_SID_VER_PART_NUM &&
+	    sgi_plat_info.config_id == SGI_CLARK_HELIOS_CONFIG_ID)
+		return sgi_clark_helios_pd_tree_desc;
+	else
 		return sgi_pd_tree_desc;
 }