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Diffstat (limited to 'arch/x86/kernel/reboot_64.c')
-rw-r--r--arch/x86/kernel/reboot_64.c171
1 files changed, 171 insertions, 0 deletions
diff --git a/arch/x86/kernel/reboot_64.c b/arch/x86/kernel/reboot_64.c
new file mode 100644
index 00000000000..368db2b9c5a
--- /dev/null
+++ b/arch/x86/kernel/reboot_64.c
@@ -0,0 +1,171 @@
+/* Various gunk just to reboot the machine. */
+#include <linux/module.h>
+#include <linux/reboot.h>
+#include <linux/init.h>
+#include <linux/smp.h>
+#include <linux/kernel.h>
+#include <linux/ctype.h>
+#include <linux/string.h>
+#include <linux/pm.h>
+#include <linux/kdebug.h>
+#include <linux/sched.h>
+#include <asm/io.h>
+#include <asm/delay.h>
+#include <asm/hw_irq.h>
+#include <asm/system.h>
+#include <asm/pgtable.h>
+#include <asm/tlbflush.h>
+#include <asm/apic.h>
+#include <asm/iommu.h>
+
+/*
+ * Power off function, if any
+ */
+void (*pm_power_off)(void);
+EXPORT_SYMBOL(pm_power_off);
+
+static long no_idt[3];
+static enum {
+ BOOT_TRIPLE = 't',
+ BOOT_KBD = 'k'
+} reboot_type = BOOT_KBD;
+static int reboot_mode = 0;
+int reboot_force;
+
+/* reboot=t[riple] | k[bd] [, [w]arm | [c]old]
+ warm Don't set the cold reboot flag
+ cold Set the cold reboot flag
+ triple Force a triple fault (init)
+ kbd Use the keyboard controller. cold reset (default)
+ force Avoid anything that could hang.
+ */
+static int __init reboot_setup(char *str)
+{
+ for (;;) {
+ switch (*str) {
+ case 'w':
+ reboot_mode = 0x1234;
+ break;
+
+ case 'c':
+ reboot_mode = 0;
+ break;
+
+ case 't':
+ case 'b':
+ case 'k':
+ reboot_type = *str;
+ break;
+ case 'f':
+ reboot_force = 1;
+ break;
+ }
+ if((str = strchr(str,',')) != NULL)
+ str++;
+ else
+ break;
+ }
+ return 1;
+}
+
+__setup("reboot=", reboot_setup);
+
+static inline void kb_wait(void)
+{
+ int i;
+
+ for (i=0; i<0x10000; i++)
+ if ((inb_p(0x64) & 0x02) == 0)
+ break;
+}
+
+void machine_shutdown(void)
+{
+ unsigned long flags;
+
+ /* Stop the cpus and apics */
+#ifdef CONFIG_SMP
+ int reboot_cpu_id;
+
+ /* The boot cpu is always logical cpu 0 */
+ reboot_cpu_id = 0;
+
+ /* Make certain the cpu I'm about to reboot on is online */
+ if (!cpu_isset(reboot_cpu_id, cpu_online_map)) {
+ reboot_cpu_id = smp_processor_id();
+ }
+
+ /* Make certain I only run on the appropriate processor */
+ set_cpus_allowed(current, cpumask_of_cpu(reboot_cpu_id));
+
+ /* O.K Now that I'm on the appropriate processor,
+ * stop all of the others.
+ */
+ smp_send_stop();
+#endif
+
+ local_irq_save(flags);
+
+#ifndef CONFIG_SMP
+ disable_local_APIC();
+#endif
+
+ disable_IO_APIC();
+
+ local_irq_restore(flags);
+
+ pci_iommu_shutdown();
+}
+
+void machine_emergency_restart(void)
+{
+ int i;
+
+ /* Tell the BIOS if we want cold or warm reboot */
+ *((unsigned short *)__va(0x472)) = reboot_mode;
+
+ for (;;) {
+ /* Could also try the reset bit in the Hammer NB */
+ switch (reboot_type) {
+ case BOOT_KBD:
+ for (i=0; i<10; i++) {
+ kb_wait();
+ udelay(50);
+ outb(0xfe,0x64); /* pulse reset low */
+ udelay(50);
+ }
+
+ case BOOT_TRIPLE:
+ __asm__ __volatile__("lidt (%0)": :"r" (&no_idt));
+ __asm__ __volatile__("int3");
+
+ reboot_type = BOOT_KBD;
+ break;
+ }
+ }
+}
+
+void machine_restart(char * __unused)
+{
+ printk("machine restart\n");
+
+ if (!reboot_force) {
+ machine_shutdown();
+ }
+ machine_emergency_restart();
+}
+
+void machine_halt(void)
+{
+}
+
+void machine_power_off(void)
+{
+ if (pm_power_off) {
+ if (!reboot_force) {
+ machine_shutdown();
+ }
+ pm_power_off();
+ }
+}
+