[PATCH] kexec: x86: resture apic virtual wire mode on shutdown
[linux-2.6.git] / arch / i386 / kernel / io_apic.c
index 3c2b3bd..fc81c8c 100644 (file)
@@ -1636,12 +1636,43 @@ static void __init enable_IO_APIC(void)
  */
 void disable_IO_APIC(void)
 {
+       int pin;
        /*
         * Clear the IO-APIC before rebooting:
         */
        clear_IO_APIC();
 
-       disconnect_bsp_APIC();
+       /*
+        * If the i82559 is routed through an IOAPIC
+        * Put that IOAPIC in virtual wire mode
+        * so legacy interrups can be delivered.
+        */
+       pin = find_isa_irq_pin(0, mp_ExtINT);
+       if (pin != -1) {
+               struct IO_APIC_route_entry entry;
+               unsigned long flags;
+
+               memset(&entry, 0, sizeof(entry));
+               entry.mask            = 0; /* Enabled */
+               entry.trigger         = 0; /* Edge */
+               entry.irr             = 0;
+               entry.polarity        = 0; /* High */
+               entry.delivery_status = 0;
+               entry.dest_mode       = 0; /* Physical */
+               entry.delivery_mode   = 7; /* ExtInt */
+               entry.vector          = 0;
+               entry.dest.physical.physical_dest = 0;
+
+
+               /*
+                * Add it to the IO-APIC irq-routing table:
+                */
+               spin_lock_irqsave(&ioapic_lock, flags);
+               io_apic_write(0, 0x11+2*pin, *(((int *)&entry)+1));
+               io_apic_write(0, 0x10+2*pin, *(((int *)&entry)+0));
+               spin_unlock_irqrestore(&ioapic_lock, flags);
+       }
+       disconnect_bsp_APIC(pin != -1);
 }
 
 /*