1 files changed, 123 insertions, 3 deletions

diff --git a/arch/x86/kernel/reboot.c b/arch/x86/kernel/reboot.c
index cc5a2545dd41..61f718df6eec 100644
--- a/arch/x86/kernel/reboot.c
+++ b/arch/x86/kernel/reboot.c
@@ -21,6 +21,9 @@
 # include <asm/iommu.h>
 #endif
 
+#include <mach_ipi.h>
+
+
 /*
  * Power off function, if any
  */
@@ -36,7 +39,10 @@ int reboot_force;
 static int reboot_cpu = -1;
 #endif
 
-/* reboot=b[ios] | s[mp] | t[riple] | k[bd] | e[fi] [, [w]arm | [c]old]
+/* This is set by the PCI code if either type 1 or type 2 PCI is detected */
+bool port_cf9_safe = false;
+
+/* reboot=b[ios] | s[mp] | t[riple] | k[bd] | e[fi] [, [w]arm | [c]old] | p[ci]
    warm   Don't set the cold reboot flag
    cold   Set the cold reboot flag
    bios   Reboot by jumping through the BIOS (only for X86_32)
@@ -45,6 +51,7 @@ static int reboot_cpu = -1;
    kbd    Use the keyboard controller. cold reset (default)
    acpi   Use the RESET_REG in the FADT
    efi    Use efi reset_system runtime service
+   pci    Use the so-called "PCI reset register", CF9
    force  Avoid anything that could hang.
  */
 static int __init reboot_setup(char *str)
@@ -79,6 +86,7 @@ static int __init reboot_setup(char *str)
                 case 'k':
                 case 't':
                 case 'e':
+                case 'p':
                         reboot_type = *str;
                         break;
 
@@ -404,12 +412,27 @@ static void native_machine_emergency_restart(void)
                         reboot_type = BOOT_KBD;
                         break;
 
-
                 case BOOT_EFI:
                         if (efi_enabled)
-                                efi.reset_system(reboot_mode ? EFI_RESET_WARM : EFI_RESET_COLD,
+                                efi.reset_system(reboot_mode ?
+                                                 EFI_RESET_WARM :
+                                                 EFI_RESET_COLD,
                                                  EFI_SUCCESS, 0, NULL);
+                        reboot_type = BOOT_KBD;
+                        break;
 
+                case BOOT_CF9:
+                        port_cf9_safe = true;
+                        /* fall through */
+
+                case BOOT_CF9_COND:
+                        if (port_cf9_safe) {
+                                u8 cf9 = inb(0xcf9) & ~6;
+                                outb(cf9|2, 0xcf9); /* Request hard reset */
+                                udelay(50);
+                                outb(cf9|6, 0xcf9); /* Actually do the reset */
+                                udelay(50);
+                        }
                         reboot_type = BOOT_KBD;
                         break;
                 }
@@ -470,6 +493,11 @@ static void native_machine_restart(char *__unused)
 
 static void native_machine_halt(void)
 {
+        /* stop other cpus and apics */
+        machine_shutdown();
+
+        /* stop this cpu */
+        stop_this_cpu(NULL);
 }
 
 static void native_machine_power_off(void)
@@ -523,3 +551,95 @@ void machine_crash_shutdown(struct pt_regs *regs)
         machine_ops.crash_shutdown(regs);
 }
 #endif
+
+
+#if defined(CONFIG_SMP)
+
+/* This keeps a track of which one is crashing cpu. */
+static int crashing_cpu;
+static nmi_shootdown_cb shootdown_callback;
+
+static atomic_t waiting_for_crash_ipi;
+
+static int crash_nmi_callback(struct notifier_block *self,
+                        unsigned long val, void *data)
+{
+        int cpu;
+
+        if (val != DIE_NMI_IPI)
+                return NOTIFY_OK;
+
+        cpu = raw_smp_processor_id();
+
+        /* Don't do anything if this handler is invoked on crashing cpu.
+         * Otherwise, system will completely hang. Crashing cpu can get
+         * an NMI if system was initially booted with nmi_watchdog parameter.
+         */
+        if (cpu == crashing_cpu)
+                return NOTIFY_STOP;
+        local_irq_disable();
+
+        shootdown_callback(cpu, (struct die_args *)data);
+
+        atomic_dec(&waiting_for_crash_ipi);
+        /* Assume hlt works */
+        halt();
+        for (;;)
+                cpu_relax();
+
+        return 1;
+}
+
+static void smp_send_nmi_allbutself(void)
+{
+        cpumask_t mask = cpu_online_map;
+        cpu_clear(safe_smp_processor_id(), mask);
+        if (!cpus_empty(mask))
+                send_IPI_mask(mask, NMI_VECTOR);
+}
+
+static struct notifier_block crash_nmi_nb = {
+        .notifier_call = crash_nmi_callback,
+};
+
+/* Halt all other CPUs, calling the specified function on each of them
+ *
+ * This function can be used to halt all other CPUs on crash
+ * or emergency reboot time. The function passed as parameter
+ * will be called inside a NMI handler on all CPUs.
+ */
+void nmi_shootdown_cpus(nmi_shootdown_cb callback)
+{
+        unsigned long msecs;
+        local_irq_disable();
+
+        /* Make a note of crashing cpu. Will be used in NMI callback.*/
+        crashing_cpu = safe_smp_processor_id();
+
+        shootdown_callback = callback;
+
+        atomic_set(&waiting_for_crash_ipi, num_online_cpus() - 1);
+        /* Would it be better to replace the trap vector here? */
+        if (register_die_notifier(&crash_nmi_nb))
+                return;         /* return what? */
+        /* Ensure the new callback function is set before sending
+         * out the NMI
+         */
+        wmb();
+
+        smp_send_nmi_allbutself();
+
+        msecs = 1000; /* Wait at most a second for the other cpus to stop */
+        while ((atomic_read(&waiting_for_crash_ipi) > 0) && msecs) {
+                mdelay(1);
+                msecs--;
+        }
+
+        /* Leave the nmi callback set */
+}
+#else /* !CONFIG_SMP */
+void nmi_shootdown_cpus(nmi_shootdown_cb callback)
+{
+        /* No other CPUs to shoot down */
+}
+#endif