release/src-rt-6.x/linux/linux-2.6/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 void machine_shutdown(void)
  33 {
  34 }
  35
  36 void machine_crash_shutdown(struct pt_regs *regs)
  37 {
  38 }
  39
  40 /*
  41  * Do what every setup is needed on image and the
  42  * reboot code buffer to allow us to avoid allocations
  43  * later.
  44  */
  45 int machine_kexec_prepare(struct kimage *image)
  46 {
  47         return 0;
  48 }
  49
  50 void machine_kexec_cleanup(struct kimage *image)
  51 {
  52 }
  53
  54 static void kexec_info(struct kimage *image)
  55 {
  56         int i;
  57         printk("kexec information\n");
  58         for (i = 0; i < image->nr_segments; i++) {
  59                 printk("  segment[%d]: 0x%08x - 0x%08x (0x%08x)\n",
  60                        i,
  61                        (unsigned int)image->segment[i].mem,
  62                        (unsigned int)image->segment[i].mem +
  63                                      image->segment[i].memsz,
  64                        (unsigned int)image->segment[i].memsz);
  65         }
  66         printk("  start     : 0x%08x\n\n", (unsigned int)image->start);
  67 }
  68
  69 /*
  70  * Do not allocate memory (or fail in any way) in machine_kexec().
  71  * We are past the point of no return, committed to rebooting now.
  72  */
  73 NORET_TYPE void machine_kexec(struct kimage *image)
  74 {
  75
  76         unsigned long page_list;
  77         unsigned long reboot_code_buffer;
  78         unsigned long vbr_reg;
  79         relocate_new_kernel_t rnk;
  80
  81 #if defined(CONFIG_SH_STANDARD_BIOS)
  82         vbr_reg = ((unsigned long )gdb_vbr_vector) - 0x100;
  83 #else
  84         vbr_reg = 0x80000000;  // dummy
  85 #endif
  86         /* Interrupts aren't acceptable while we reboot */
  87         local_irq_disable();
  88
  89         page_list = image->head;
  90
  91         /* we need both effective and real address here */
  92         reboot_code_buffer =
  93                         (unsigned long)page_address(image->control_code_page);
  94
  95         /* copy our kernel relocation code to the control code page */
  96         memcpy((void *)reboot_code_buffer, relocate_new_kernel,
  97                                                 relocate_new_kernel_size);
  98
  99         kexec_info(image);
 100         flush_cache_all();
 101
 102         /* now call it */
 103         rnk = (relocate_new_kernel_t) reboot_code_buffer;
 104         (*rnk)(page_list, reboot_code_buffer, image->start, vbr_reg);
 105 }
 106
 107 /* crashkernel=size@addr specifies the location to reserve for
 108  * a crash kernel.  By reserving this memory we guarantee
 109  * that linux never sets it up as a DMA target.
 110  * Useful for holding code to do something appropriate
 111  * after a kernel panic.
 112  */
 113 static int __init parse_crashkernel(char *arg)
 114 {
 115         unsigned long size, base;
 116         size = memparse(arg, &arg);
 117         if (*arg == '@') {
 118                 base = memparse(arg+1, &arg);
 119                 /* FIXME: Do I want a sanity check
 120                  * to validate the memory range?
 121                  */
 122                 crashk_res.start = base;
 123                 crashk_res.end   = base + size - 1;
 124         }
 125         return 0;
 126 }
 127 early_param("crashkernel", parse_crashkernel);