[IA64-SGI] Altix: enable poweroff

This patch adds the necessary "hook" to allow SGI/SN
machines to perform a system power off upon a 
'init 0', 'halt -p', 'poweroff' or 'shutdown -h'.

The "hook" is to set the pm_power_off callback
to ia64_sn_power_down(). pm_power_off is checked
in machine_power_off()/do_poweroff() and, if set, is executed. 
ia64_sn_power_down() is a function already present (but not 
used currently) in the sn kernel.
ia64_sn_power_down() makes a SAL call to execute the
power off.

Signed-off-by: Aaron J Young <ayoung@sgi.com>
Signed-off-by: Tony Luck <tony.luck@intel.com>

1 files changed, 9 insertions, 0 deletions

diff --git a/arch/ia64/sn/kernel/setup.c b/arch/ia64/sn/kernel/setup.c
index f0306b516af..d35f2a6f9c9 100644
--- a/arch/ia64/sn/kernel/setup.c
+++ b/arch/ia64/sn/kernel/setup.c
@@ -29,6 +29,7 @@
 #include <linux/sched.h>
 #include <linux/root_dev.h>
 #include <linux/nodemask.h>
+#include <linux/pm.h>
 
 #include <asm/io.h>
 #include <asm/sal.h>
@@ -353,6 +354,14 @@ void __init sn_setup(char **cmdline_p)
         screen_info = sn_screen_info;
 
         sn_timer_init();
+
+        /*
+         * set pm_power_off to a SAL call to allow
+         * sn machines to power off. The SAL call can be replaced
+         * by an ACPI interface call when ACPI is fully implemented
+         * for sn.
+         */
+        pm_power_off = ia64_sn_power_down;
 }
 
 /**