[IA64] workaround tiger ia64_sal_get_physical_id_info hang

This fixes regression introduced in 113134f

Intel Tiger platforms hang when calling SAL_GET_PHYSICAL_ID_INFO
instead of properly returning -1 for unimplemented, so add a
version check.

SGI Altix platforms have an incorrect SAL version hard-coded into
their prom -- they encode 2.9, but actually implement 3.2 -- so
fix it up and allow ia64_sal_get_physical_id_info to keep
working.

Signed-off-by: Alex Chiang <achiang@hp.com>
Acked-by: Russ Anderson <rja@sgi.com>
Signed-off-by: Tony Luck <tony.luck@intel.com>

arch/ia64/kernel/sal.c

@@ -109,6 +109,13 @@ check_versions (struct ia64_sal_systab *systab)
 		sal_revision = SAL_VERSION_CODE(2, 8);
 		sal_version = SAL_VERSION_CODE(0, 0);
 	}
+
+	if (ia64_platform_is("sn2") && (sal_revision == SAL_VERSION_CODE(2, 9)))
+		/*
+		 * SGI Altix has hard-coded version 2.9 in their prom
+		 * but they actually implement 3.2, so let's fix it here.
+		 */
+		sal_revision = SAL_VERSION_CODE(3, 2);
 }
 
 static void __init

include/asm-ia64/sal.h

@@ -807,6 +807,10 @@ static inline s64
 ia64_sal_physical_id_info(u16 *splid)
 {
 	struct ia64_sal_retval isrv;
+
+	if (sal_revision < SAL_VERSION_CODE(3,2))
+		return -1;
+
 	SAL_CALL(isrv, SAL_PHYSICAL_ID_INFO, 0, 0, 0, 0, 0, 0, 0);
 	if (splid)
 		*splid = isrv.v0;