arch/powerpc/kernel/machine_kexec.c

   1 /*
   2  * Code to handle transition of Linux booting another kernel.
   3  *
   4  * Copyright (C) 2002-2003 Eric Biederman  <ebiederm@xmission.com>
   5  * GameCube/ppc32 port Copyright (C) 2004 Albert Herranz
   6  * Copyright (C) 2005 IBM Corporation.
   7  *
   8  * This source code is licensed under the GNU General Public License,
   9  * Version 2.  See the file COPYING for more details.
  10  */
  11
  12 #include <linux/kexec.h>
  13 #include <linux/reboot.h>
  14 #include <linux/threads.h>
  15 #include <asm/machdep.h>
  16
  17 void machine_crash_shutdown(struct pt_regs *regs)
  18 {
  19         if (ppc_md.machine_crash_shutdown)
  20                 ppc_md.machine_crash_shutdown(regs);
  21 }
  22
  23 /*
  24  * Do what every setup is needed on image and the
  25  * reboot code buffer to allow us to avoid allocations
  26  * later.
  27  */
  28 int machine_kexec_prepare(struct kimage *image)
  29 {
  30         if (ppc_md.machine_kexec_prepare)
  31                 return ppc_md.machine_kexec_prepare(image);
  32         /*
  33          * Fail if platform doesn't provide its own machine_kexec_prepare
  34          * implementation.
  35          */
  36         return -ENOSYS;
  37 }
  38
  39 void machine_kexec_cleanup(struct kimage *image)
  40 {
  41         if (ppc_md.machine_kexec_cleanup)
  42                 ppc_md.machine_kexec_cleanup(image);
  43 }
  44
  45 /*
  46  * Do not allocate memory (or fail in any way) in machine_kexec().
  47  * We are past the point of no return, committed to rebooting now.
  48  */
  49 NORET_TYPE void machine_kexec(struct kimage *image)
  50 {
  51         if (ppc_md.machine_kexec)
  52                 ppc_md.machine_kexec(image);
  53         else {
  54                 /*
  55                  * Fall back to normal restart if platform doesn't provide
  56                  * its own kexec function, and user insist to kexec...
  57                  */
  58                 machine_restart(NULL);
  59         }
  60         for(;;);
  61 }