arch/sh/kernel/machine_kexec.c

   1 /*
   2  * machine_kexec.c - handle transition of Linux booting another kernel
   3  * Copyright (C) 2002-2003 Eric Biederman  <ebiederm@xmission.com>
   4  *
   5  * GameCube/ppc32 port Copyright (C) 2004 Albert Herranz
   6  * LANDISK/sh4 supported by kogiidena
   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/mm.h>
  13 #include <linux/kexec.h>
  14 #include <linux/delay.h>
  15 #include <linux/reboot.h>
  16 #include <asm/pgtable.h>
  17 #include <asm/pgalloc.h>
  18 #include <asm/mmu_context.h>
  19 #include <asm/io.h>
  20 #include <asm/cacheflush.h>
  21
  22 typedef NORET_TYPE void (*relocate_new_kernel_t)(
  23                                 unsigned long indirection_page,
  24                                 unsigned long reboot_code_buffer,
  25                                 unsigned long start_address,
  26                                 unsigned long vbr_reg) ATTRIB_NORET;
  27
  28 extern const unsigned char relocate_new_kernel[];
  29 extern const unsigned int relocate_new_kernel_size;
  30 extern void *gdb_vbr_vector;
  31
  32 /*
  33  * Provide a dummy crash_notes definition while crash dump arrives to ppc.
  34  * This prevents breakage of crash_notes attribute in kernel/ksysfs.c.
  35  */
  36 void *crash_notes = NULL;
  37
  38 void machine_shutdown(void)
  39 {
  40 }
  41
  42 void machine_crash_shutdown(struct pt_regs *regs)
  43 {
  44 }
  45
  46 /*
  47  * Do what every setup is needed on image and the
  48  * reboot code buffer to allow us to avoid allocations
  49  * later.
  50  */
  51 int machine_kexec_prepare(struct kimage *image)
  52 {
  53         return 0;
  54 }
  55
  56 void machine_kexec_cleanup(struct kimage *image)
  57 {
  58 }
  59
  60 static void kexec_info(struct kimage *image)
  61 {
  62         int i;
  63         printk("kexec information\n");
  64         for (i = 0; i < image->nr_segments; i++) {
  65                 printk("  segment[%d]: 0x%08x - 0x%08x (0x%08x)\n",
  66                        i,
  67                        (unsigned int)image->segment[i].mem,
  68                        (unsigned int)image->segment[i].mem + image->segment[i].memsz,
  69                        (unsigned int)image->segment[i].memsz);
  70         }
  71         printk("  start     : 0x%08x\n\n", (unsigned int)image->start);
  72 }
  73
  74
  75 /*
  76  * Do not allocate memory (or fail in any way) in machine_kexec().
  77  * We are past the point of no return, committed to rebooting now.
  78  */
  79 NORET_TYPE void machine_kexec(struct kimage *image)
  80 {
  81
  82         unsigned long page_list;
  83         unsigned long reboot_code_buffer;
  84         unsigned long vbr_reg;
  85         relocate_new_kernel_t rnk;
  86
  87 #if defined(CONFIG_SH_STANDARD_BIOS)
  88         vbr_reg = ((unsigned long )gdb_vbr_vector) - 0x100;
  89 #else
  90         vbr_reg = 0x80000000;  // dummy
  91 #endif
  92         /* Interrupts aren't acceptable while we reboot */
  93         local_irq_disable();
  94
  95         page_list = image->head;
  96
  97         /* we need both effective and real address here */
  98         reboot_code_buffer =
  99                         (unsigned long)page_address(image->control_code_page);
 100
 101         /* copy our kernel relocation code to the control code page */
 102         memcpy((void *)reboot_code_buffer, relocate_new_kernel,
 103                                                 relocate_new_kernel_size);
 104
 105         kexec_info(image);
 106         flush_cache_all();
 107
 108         /* now call it */
 109         rnk = (relocate_new_kernel_t) reboot_code_buffer;
 110         (*rnk)(page_list, reboot_code_buffer, image->start, vbr_reg);
 111 }
 112