arch/powerpc/kexec/core_32.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  * PPC32 code to handle Linux booting another kernel.
   4  *
   5  * Copyright (C) 2002-2003 Eric Biederman  <ebiederm@xmission.com>
   6  * GameCube/ppc32 port Copyright (C) 2004 Albert Herranz
   7  * Copyright (C) 2005 IBM Corporation.
   8  */
   9
  10 #include <linux/kexec.h>
  11 #include <linux/mm.h>
  12 #include <linux/string.h>
  13 #include <asm/cacheflush.h>
  14 #include <asm/hw_irq.h>
  15 #include <asm/io.h>
  16
  17 typedef void (*relocate_new_kernel_t)(
  18                                 unsigned long indirection_page,
  19                                 unsigned long reboot_code_buffer,
  20                                 unsigned long start_address) __noreturn;
  21
  22 /*
  23  * This is a generic machine_kexec function suitable at least for
  24  * non-OpenFirmware embedded platforms.
  25  * It merely copies the image relocation code to the control page and
  26  * jumps to it.
  27  * A platform specific function may just call this one.
  28  */
  29 void default_machine_kexec(struct kimage *image)
  30 {
  31         extern const unsigned int relocate_new_kernel_size;
  32         unsigned long page_list;
  33         unsigned long reboot_code_buffer, reboot_code_buffer_phys;
  34         relocate_new_kernel_t rnk;
  35
  36         /* Interrupts aren't acceptable while we reboot */
  37         local_irq_disable();
  38
  39         /* mask each interrupt so we are in a more sane state for the
  40          * kexec kernel */
  41         machine_kexec_mask_interrupts();
  42
  43         page_list = image->head;
  44
  45         /* we need both effective and real address here */
  46         reboot_code_buffer =
  47                         (unsigned long)page_address(image->control_code_page);
  48         reboot_code_buffer_phys = virt_to_phys((void *)reboot_code_buffer);
  49
  50         /* copy our kernel relocation code to the control code page */
  51         memcpy((void *)reboot_code_buffer, relocate_new_kernel,
  52                                                 relocate_new_kernel_size);
  53
  54         flush_icache_range(reboot_code_buffer,
  55                                 reboot_code_buffer + KEXEC_CONTROL_PAGE_SIZE);
  56         printk(KERN_INFO "Bye!\n");
  57
  58         if (!IS_ENABLED(CONFIG_FSL_BOOKE) && !IS_ENABLED(CONFIG_44x))
  59                 relocate_new_kernel(page_list, reboot_code_buffer_phys, image->start);
  60
  61         /* now call it */
  62         rnk = (relocate_new_kernel_t) reboot_code_buffer;
  63         (*rnk)(page_list, reboot_code_buffer_phys, image->start);
  64 }
  65
  66 int default_machine_kexec_prepare(struct kimage *image)
  67 {
  68         return 0;
  69 }