[PATCH V2 2/2] MIPS: Provide fallback reboot/poweroff/halt implementations

[Andrew Bresticker <abrestic@xxxxxxxxxxxx>]

If a machine-specific hook is not implemented for restart, poweroff,
or halt, fall back to halting secondary CPUs, disabling interrupts,
and spinning.  In the case of restart, attempt to restart the system
via do_kernel_restart() (which will call any registered restart
handlers) before halting.

Signed-off-by: Andrew Bresticker <abrestic@xxxxxxxxxxxx>
Cc: James Hogan <james.hogan@xxxxxxxxxx>
Cc: Maciej W. Rozycki <macro@xxxxxxxxxxxxxx>
---
Changes from v1:
 - disable preemption before calling smp_send_stop()
 - add a 1s delay after do_kernel_restart()
---
 arch/mips/kernel/reset.c | 25 +++++++++++++++++++++++++
 1 file changed, 25 insertions(+)

diff --git a/arch/mips/kernel/reset.c b/arch/mips/kernel/reset.c
index 07fc524..7c746d3 100644
--- a/arch/mips/kernel/reset.c
+++ b/arch/mips/kernel/reset.c
@@ -11,6 +11,7 @@
 #include <linux/pm.h>
 #include <linux/types.h>
 #include <linux/reboot.h>
+#include <linux/delay.h>
 
 #include <asm/reboot.h>
 
@@ -29,16 +30,40 @@ void machine_restart(char *command)
 {
 	if (_machine_restart)
 		_machine_restart(command);
+
+#ifdef CONFIG_SMP
+	preempt_disable();
+	smp_send_stop();
+#endif
+	do_kernel_restart(command);
+	mdelay(1000);
+	pr_emerg("Reboot failed -- System halted\n");
+	local_irq_disable();
+	while (1);
 }
 
 void machine_halt(void)
 {
 	if (_machine_halt)
 		_machine_halt();
+
+#ifdef CONFIG_SMP
+	preempt_disable();
+	smp_send_stop();
+#endif
+	local_irq_disable();
+	while (1);
 }
 
 void machine_power_off(void)
 {
 	if (pm_power_off)
 		pm_power_off();
+
+#ifdef CONFIG_SMP
+	preempt_disable();
+	smp_send_stop();
+#endif
+	local_irq_disable();
+	while (1);
 }
-- 
2.2.0.rc0.207.ga3a616c