arch/powerpc/kernel/machine_kexec_32.c

   1 /*
   2  * PPC32 code to handle 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/mm.h>
  14 #include <linux/string.h>
  15 #include <asm/cacheflush.h>
  16 #include <asm/hw_irq.h>
  17 #include <asm/io.h>
  18
  19 typedef void (*relocate_new_kernel_t)(
  20                                 unsigned long indirection_page,
  21                                 unsigned long reboot_code_buffer,
  22                                 unsigned long start_address) __noreturn;
  23
  24 /*
  25  * This is a generic machine_kexec function suitable at least for
  26  * non-OpenFirmware embedded platforms.
  27  * It merely copies the image relocation code to the control page and
  28  * jumps to it.
  29  * A platform specific function may just call this one.
  30  */
  31 void default_machine_kexec(struct kimage *image)
  32 {
  33         extern const unsigned char relocate_new_kernel[];
  34         extern const unsigned int relocate_new_kernel_size;
  35         unsigned long page_list;
  36         unsigned long reboot_code_buffer, reboot_code_buffer_phys;
  37         relocate_new_kernel_t rnk;
  38
  39         /* Interrupts aren't acceptable while we reboot */
  40         local_irq_disable();
  41
  42         /* mask each interrupt so we are in a more sane state for the
  43          * kexec kernel */
  44         machine_kexec_mask_interrupts();
  45
  46         page_list = image->head;
  47
  48         /* we need both effective and real address here */
  49         reboot_code_buffer =
  50                         (unsigned long)page_address(image->control_code_page);
  51         reboot_code_buffer_phys = virt_to_phys((void *)reboot_code_buffer);
  52
  53         /* copy our kernel relocation code to the control code page */
  54         memcpy((void *)reboot_code_buffer, relocate_new_kernel,
  55                                                 relocate_new_kernel_size);
  56
  57         flush_icache_range(reboot_code_buffer,
  58                                 reboot_code_buffer + KEXEC_CONTROL_PAGE_SIZE);
  59         printk(KERN_INFO "Bye!\n");
  60
  61         /* now call it */
  62         rnk = (relocate_new_kernel_t) reboot_code_buffer;
  63         (*rnk)(page_list, reboot_code_buffer_phys, image->start);
  64 }
  65
  66 int default_machine_kexec_prepare(struct kimage *image)
  67 {
  68         return 0;
  69 }