arch/arm/kernel/machine_kexec.c

   1 /*
   2  * machine_kexec.c - handle transition of Linux booting another kernel
   3  */
   4
   5 #include <linux/mm.h>
   6 #include <linux/kexec.h>
   7 #include <linux/delay.h>
   8 #include <linux/reboot.h>
   9 #include <linux/io.h>
  10 #include <asm/pgtable.h>
  11 #include <asm/pgalloc.h>
  12 #include <asm/mmu_context.h>
  13 #include <asm/cacheflush.h>
  14 #include <asm/mach-types.h>
  15
  16 extern const unsigned char relocate_new_kernel[];
  17 extern const unsigned int relocate_new_kernel_size;
  18
  19 extern void setup_mm_for_reboot(char mode);
  20
  21 extern unsigned long kexec_start_address;
  22 extern unsigned long kexec_indirection_page;
  23 extern unsigned long kexec_mach_type;
  24 extern unsigned long kexec_boot_atags;
  25
  26 /*
  27  * Provide a dummy crash_notes definition while crash dump arrives to arm.
  28  * This prevents breakage of crash_notes attribute in kernel/ksysfs.c.
  29  */
  30
  31 int machine_kexec_prepare(struct kimage *image)
  32 {
  33         return 0;
  34 }
  35
  36 void machine_kexec_cleanup(struct kimage *image)
  37 {
  38 }
  39
  40 void machine_shutdown(void)
  41 {
  42 }
  43
  44 void machine_crash_shutdown(struct pt_regs *regs)
  45 {
  46 }
  47
  48 void machine_kexec(struct kimage *image)
  49 {
  50         unsigned long page_list;
  51         unsigned long reboot_code_buffer_phys;
  52         void *reboot_code_buffer;
  53
  54
  55         page_list = image->head & PAGE_MASK;
  56
  57         /* we need both effective and real address here */
  58         reboot_code_buffer_phys =
  59             page_to_pfn(image->control_code_page) << PAGE_SHIFT;
  60         reboot_code_buffer = page_address(image->control_code_page);
  61
  62         /* Prepare parameters for reboot_code_buffer*/
  63         kexec_start_address = image->start;
  64         kexec_indirection_page = page_list;
  65         kexec_mach_type = machine_arch_type;
  66         kexec_boot_atags = image->start - KEXEC_ARM_ZIMAGE_OFFSET + KEXEC_ARM_ATAGS_OFFSET;
  67
  68         /* copy our kernel relocation code to the control code page */
  69         memcpy(reboot_code_buffer,
  70                relocate_new_kernel, relocate_new_kernel_size);
  71
  72
  73         flush_icache_range((unsigned long) reboot_code_buffer,
  74                            (unsigned long) reboot_code_buffer + KEXEC_CONTROL_PAGE_SIZE);
  75         printk(KERN_INFO "Bye!\n");
  76
  77         cpu_proc_fin();
  78         setup_mm_for_reboot(0); /* mode is not used, so just pass 0*/
  79         cpu_reset(reboot_code_buffer_phys);
  80 }