arch/mips/kernel/machine_kexec.c

   1 /*
   2  * machine_kexec.c for kexec
   3  * Created by <nschichan@corp.free.fr> on Thu Oct 12 15:15:06 2006
   4  *
   5  * This source code is licensed under the GNU General Public License,
   6  * Version 2.  See the file COPYING for more details.
   7  */
   8 #include <linux/compiler.h>
   9 #include <linux/kexec.h>
  10 #include <linux/mm.h>
  11 #include <linux/delay.h>
  12
  13 #include <asm/cacheflush.h>
  14 #include <asm/page.h>
  15
  16 extern const unsigned char relocate_new_kernel[];
  17 extern const size_t relocate_new_kernel_size;
  18
  19 extern unsigned long kexec_start_address;
  20 extern unsigned long kexec_indirection_page;
  21
  22 int (*_machine_kexec_prepare)(struct kimage *) = NULL;
  23 void (*_machine_kexec_shutdown)(void) = NULL;
  24 void (*_machine_crash_shutdown)(struct pt_regs *regs) = NULL;
  25 #ifdef CONFIG_SMP
  26 void (*relocated_kexec_smp_wait) (void *);
  27 atomic_t kexec_ready_to_reboot = ATOMIC_INIT(0);
  28 void (*_crash_smp_send_stop)(void) = NULL;
  29 #endif
  30
  31 int
  32 machine_kexec_prepare(struct kimage *kimage)
  33 {
  34         if (_machine_kexec_prepare)
  35                 return _machine_kexec_prepare(kimage);
  36         return 0;
  37 }
  38
  39 void
  40 machine_kexec_cleanup(struct kimage *kimage)
  41 {
  42 }
  43
  44 void
  45 machine_shutdown(void)
  46 {
  47         if (_machine_kexec_shutdown)
  48                 _machine_kexec_shutdown();
  49 }
  50
  51 void
  52 machine_crash_shutdown(struct pt_regs *regs)
  53 {
  54         if (_machine_crash_shutdown)
  55                 _machine_crash_shutdown(regs);
  56         else
  57                 default_machine_crash_shutdown(regs);
  58 }
  59
  60 typedef void (*noretfun_t)(void) __noreturn;
  61
  62 void
  63 machine_kexec(struct kimage *image)
  64 {
  65         unsigned long reboot_code_buffer;
  66         unsigned long entry;
  67         unsigned long *ptr;
  68
  69         reboot_code_buffer =
  70           (unsigned long)page_address(image->control_code_page);
  71
  72         kexec_start_address =
  73                 (unsigned long) phys_to_virt(image->start);
  74
  75         if (image->type == KEXEC_TYPE_DEFAULT) {
  76                 kexec_indirection_page =
  77                         (unsigned long) phys_to_virt(image->head & PAGE_MASK);
  78         } else {
  79                 kexec_indirection_page = (unsigned long)&image->head;
  80         }
  81
  82         memcpy((void*)reboot_code_buffer, relocate_new_kernel,
  83                relocate_new_kernel_size);
  84
  85         /*
  86          * The generic kexec code builds a page list with physical
  87          * addresses. they are directly accessible through KSEG0 (or
  88          * CKSEG0 or XPHYS if on 64bit system), hence the
  89          * phys_to_virt() call.
  90          */
  91         for (ptr = &image->head; (entry = *ptr) && !(entry &IND_DONE);
  92              ptr = (entry & IND_INDIRECTION) ?
  93                phys_to_virt(entry & PAGE_MASK) : ptr + 1) {
  94                 if (*ptr & IND_SOURCE || *ptr & IND_INDIRECTION ||
  95                     *ptr & IND_DESTINATION)
  96                         *ptr = (unsigned long) phys_to_virt(*ptr);
  97         }
  98
  99         /*
 100          * we do not want to be bothered.
 101          */
 102         local_irq_disable();
 103
 104         printk("Will call new kernel at %08lx\n", image->start);
 105         printk("Bye ...\n");
 106         __flush_cache_all();
 107 #ifdef CONFIG_SMP
 108         /* All secondary cpus now may jump to kexec_wait cycle */
 109         relocated_kexec_smp_wait = reboot_code_buffer +
 110                 (void *)(kexec_smp_wait - relocate_new_kernel);
 111         smp_wmb();
 112         atomic_set(&kexec_ready_to_reboot, 1);
 113 #endif
 114         ((noretfun_t) reboot_code_buffer)();
 115 }