arch/m68k/kernel/machine_kexec.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   3  * machine_kexec.c - handle transition of Linux booting another kernel
   4  */
   5 #include <linux/compiler.h>
   6 #include <linux/kexec.h>
   7 #include <linux/mm.h>
   8 #include <linux/delay.h>
   9
  10 #include <asm/cacheflush.h>
  11 #include <asm/page.h>
  12 #include <asm/setup.h>
  13
  14 extern const unsigned char relocate_new_kernel[];
  15 extern const size_t relocate_new_kernel_size;
  16
  17 int machine_kexec_prepare(struct kimage *kimage)
  18 {
  19         return 0;
  20 }
  21
  22 void machine_kexec_cleanup(struct kimage *kimage)
  23 {
  24 }
  25
  26 void machine_shutdown(void)
  27 {
  28 }
  29
  30 void machine_crash_shutdown(struct pt_regs *regs)
  31 {
  32 }
  33
  34 typedef void (*relocate_kernel_t)(unsigned long ptr,
  35                                   unsigned long start,
  36                                   unsigned long cpu_mmu_flags) __noreturn;
  37
  38 void machine_kexec(struct kimage *image)
  39 {
  40         void *reboot_code_buffer;
  41         unsigned long cpu_mmu_flags;
  42
  43         reboot_code_buffer = page_address(image->control_code_page);
  44
  45         memcpy(reboot_code_buffer, relocate_new_kernel,
  46                relocate_new_kernel_size);
  47
  48         /*
  49          * we do not want to be bothered.
  50          */
  51         local_irq_disable();
  52
  53         pr_info("Will call new kernel at 0x%08lx. Bye...\n", image->start);
  54         __flush_cache_all();
  55         cpu_mmu_flags = m68k_cputype | m68k_mmutype << 8;
  56         ((relocate_kernel_t) reboot_code_buffer)(image->head & PAGE_MASK,
  57                                                  image->start,
  58                                                  cpu_mmu_flags);
  59 }