LXR linux/arch/powerpc/kernel/machine_kexec

   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
  17typedef 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 */
  29void 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
  66int default_machine_kexec_prepare(struct kimage *image)
  67{
  68        return 0;
  69}
  70