MErge mainline into intwrap

grub-core/lib/i386/halt.c

@@ -0,0 +1,55 @@
+/*
+ *  GRUB  --  GRand Unified Bootloader
+ *  Copyright (C) 2008  Free Software Foundation, Inc.
+ *
+ *  GRUB is free software: you can redistribute it and/or modify
+ *  it under the terms of the GNU General Public License as published by
+ *  the Free Software Foundation, either version 3 of the License, or
+ *  (at your option) any later version.
+ *
+ *  GRUB is distributed in the hope that it will be useful,
+ *  but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *  GNU General Public License for more details.
+ *
+ *  You should have received a copy of the GNU General Public License
+ *  along with GRUB.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include <grub/cpu/io.h>
+#include <grub/misc.h>
+
+const char bochs_shutdown[] = "Shutdown";
+
+/*
+ *  This call is special...  it never returns...  in fact it should simply
+ *  hang at this point!
+ */
+static inline void  __attribute__ ((noreturn))
+stop (void)
+{
+  asm volatile ("cli");
+  while (1)
+    {
+      asm volatile ("hlt");
+    }
+}
+
+void
+grub_halt (void)
+{
+  unsigned int i;
+
+  /* Disable interrupts.  */
+  __asm__ __volatile__ ("cli");
+
+  /* Bochs, QEMU, etc.  */
+  for (i = 0; i < sizeof (bochs_shutdown) - 1; i++)
+    grub_outb (bochs_shutdown[i], 0x8900);
+
+  grub_printf ("GRUB doesn't know how to halt this machine yet!\n");
+
+  /* In order to return we'd have to check what the previous status of IF
+     flag was.  But user most likely doesn't want to return anyway ...  */
+  stop ();
+}