[IA64] Increase max node count on SN platforms

Add a configuration option to allow the maximum
number of nodes to be configurable for GENERIC or SN
kernels.
Signed-off-by: Jack Steiner <steiner@sgi.com>
Signed-off-by: Tony Luck <tony.luck@intel.com>

arch/ia64/Kconfig

@@ -252,6 +252,15 @@ config NR_CPUS
 	  than 64 will cause the use of a CPU mask array, causing a small
 	  performance hit.
 
+config IA64_NR_NODES
+	int "Maximum number of NODEs (256-1024)" if (IA64_SGI_SN2 || IA64_GENERIC)
+	range 256 1024
+	depends on IA64_SGI_SN2 || IA64_GENERIC
+	default "256"
+	help
+	  This option specifies the maximum number of nodes in your SSI system.
+	  If in doubt, use the default.
+
 config HOTPLUG_CPU
 	bool "Support for hot-pluggable CPUs (EXPERIMENTAL)"
 	depends on SMP && EXPERIMENTAL

include/asm-ia64/numnodes.h

@@ -3,13 +3,18 @@
 
 #ifdef CONFIG_IA64_DIG
 /* Max 8 Nodes */
-#define NODES_SHIFT	3
+#  define NODES_SHIFT	3
 #elif defined(CONFIG_IA64_HP_ZX1) || defined(CONFIG_IA64_HP_ZX1_SWIOTLB)
 /* Max 32 Nodes */
-#define NODES_SHIFT	5
+#  define NODES_SHIFT	5
 #elif defined(CONFIG_IA64_SGI_SN2) || defined(CONFIG_IA64_GENERIC)
-/* Max 256 Nodes */
-#define NODES_SHIFT	8
+#  if CONFIG_IA64_NR_NODES == 256
+#    define NODES_SHIFT	8
+#  elif CONFIG_IA64_NR_NODES <= 512
+#    define NODES_SHIFT    9
+#  elif CONFIG_IA64_NR_NODES <= 1024
+#    define NODES_SHIFT    10
+#  endif
 #endif
 
 #endif /* _ASM_MAX_NUMNODES_H */