arch/sh/kernel/machine_kexec.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   3  * machine_kexec.c - handle transition of Linux booting another kernel
   4  * Copyright (C) 2002-2003 Eric Biederman  <ebiederm@xmission.com>
   5  *
   6  * GameCube/ppc32 port Copyright (C) 2004 Albert Herranz
   7  * LANDISK/sh4 supported by kogiidena
   8  */
   9 #include <linux/mm.h>
  10 #include <linux/kexec.h>
  11 #include <linux/delay.h>
  12 #include <linux/reboot.h>
  13 #include <linux/numa.h>
  14 #include <linux/ftrace.h>
  15 #include <linux/suspend.h>
  16 #include <linux/memblock.h>
  17 #include <asm/mmu_context.h>
  18 #include <asm/io.h>
  19 #include <asm/cacheflush.h>
  20 #include <asm/sh_bios.h>
  21 #include <asm/reboot.h>
  22
  23 typedef void (*relocate_new_kernel_t)(unsigned long indirection_page,
  24                                       unsigned long reboot_code_buffer,
  25                                       unsigned long start_address);
  26
  27 extern const unsigned char relocate_new_kernel[];
  28 extern const unsigned int relocate_new_kernel_size;
  29 extern void *vbr_base;
  30
  31 void native_machine_crash_shutdown(struct pt_regs *regs)
  32 {
  33         /* Nothing to do for UP, but definitely broken for SMP.. */
  34 }
  35
  36 /*
  37  * Do what every setup is needed on image and the
  38  * reboot code buffer to allow us to avoid allocations
  39  * later.
  40  */
  41 int machine_kexec_prepare(struct kimage *image)
  42 {
  43         return 0;
  44 }
  45
  46 void machine_kexec_cleanup(struct kimage *image)
  47 {
  48 }
  49
  50 static void kexec_info(struct kimage *image)
  51 {
  52         int i;
  53         printk("kexec information\n");
  54         for (i = 0; i < image->nr_segments; i++) {
  55                 printk("  segment[%d]: 0x%08x - 0x%08x (0x%08x)\n",
  56                        i,
  57                        (unsigned int)image->segment[i].mem,
  58                        (unsigned int)image->segment[i].mem +
  59                                      image->segment[i].memsz,
  60                        (unsigned int)image->segment[i].memsz);
  61         }
  62         printk("  start     : 0x%08x\n\n", (unsigned int)image->start);
  63 }
  64
  65 /*
  66  * Do not allocate memory (or fail in any way) in machine_kexec().
  67  * We are past the point of no return, committed to rebooting now.
  68  */
  69 void machine_kexec(struct kimage *image)
  70 {
  71         unsigned long page_list;
  72         unsigned long reboot_code_buffer;
  73         relocate_new_kernel_t rnk;
  74         unsigned long entry;
  75         unsigned long *ptr;
  76         int save_ftrace_enabled;
  77
  78         /*
  79          * Nicked from the mips version of machine_kexec():
  80          * The generic kexec code builds a page list with physical
  81          * addresses. Use phys_to_virt() to convert them to virtual.
  82          */
  83         for (ptr = &image->head; (entry = *ptr) && !(entry & IND_DONE);
  84              ptr = (entry & IND_INDIRECTION) ?
  85                phys_to_virt(entry & PAGE_MASK) : ptr + 1) {
  86                 if (*ptr & IND_SOURCE || *ptr & IND_INDIRECTION ||
  87                     *ptr & IND_DESTINATION)
  88                         *ptr = (unsigned long) phys_to_virt(*ptr);
  89         }
  90
  91 #ifdef CONFIG_KEXEC_JUMP
  92         if (image->preserve_context)
  93                 save_processor_state();
  94 #endif
  95
  96         save_ftrace_enabled = __ftrace_enabled_save();
  97
  98         /* Interrupts aren't acceptable while we reboot */
  99         local_irq_disable();
 100
 101         page_list = image->head;
 102
 103         /* we need both effective and real address here */
 104         reboot_code_buffer =
 105                         (unsigned long)page_address(image->control_code_page);
 106
 107         /* copy our kernel relocation code to the control code page */
 108         memcpy((void *)reboot_code_buffer, relocate_new_kernel,
 109                                                 relocate_new_kernel_size);
 110
 111         kexec_info(image);
 112         flush_cache_all();
 113
 114         sh_bios_vbr_reload();
 115
 116         /* now call it */
 117         rnk = (relocate_new_kernel_t) reboot_code_buffer;
 118         (*rnk)(page_list, reboot_code_buffer,
 119                (unsigned long)phys_to_virt(image->start));
 120
 121 #ifdef CONFIG_KEXEC_JUMP
 122         asm volatile("ldc %0, vbr" : : "r" (&vbr_base) : "memory");
 123
 124         if (image->preserve_context)
 125                 restore_processor_state();
 126
 127         /* Convert page list back to physical addresses, what a mess. */
 128         for (ptr = &image->head; (entry = *ptr) && !(entry & IND_DONE);
 129              ptr = (*ptr & IND_INDIRECTION) ?
 130                phys_to_virt(*ptr & PAGE_MASK) : ptr + 1) {
 131                 if (*ptr & IND_SOURCE || *ptr & IND_INDIRECTION ||
 132                     *ptr & IND_DESTINATION)
 133                         *ptr = virt_to_phys(*ptr);
 134         }
 135 #endif
 136
 137         __ftrace_enabled_restore(save_ftrace_enabled);
 138 }
 139
 140 void __init reserve_crashkernel(void)
 141 {
 142         unsigned long long crash_size, crash_base;
 143         int ret;
 144
 145         if (!IS_ENABLED(CONFIG_CRASH_RESERVE))
 146                 return;
 147
 148         ret = parse_crashkernel(boot_command_line, memblock_phys_mem_size(),
 149                         &crash_size, &crash_base, NULL, NULL);
 150         if (ret == 0 && crash_size > 0) {
 151                 crashk_res.start = crash_base;
 152                 crashk_res.end = crash_base + crash_size - 1;
 153         }
 154
 155         if (crashk_res.end == crashk_res.start)
 156                 goto disable;
 157
 158         crash_size = PAGE_ALIGN(resource_size(&crashk_res));
 159         if (!crashk_res.start) {
 160                 unsigned long max = memblock_end_of_DRAM() - memory_limit;
 161                 crashk_res.start = memblock_phys_alloc_range(crash_size,
 162                                                              PAGE_SIZE, 0, max);
 163                 if (!crashk_res.start) {
 164                         pr_err("crashkernel allocation failed\n");
 165                         goto disable;
 166                 }
 167         } else {
 168                 ret = memblock_reserve(crashk_res.start, crash_size);
 169                 if (unlikely(ret < 0)) {
 170                         pr_err("crashkernel reservation failed - "
 171                                "memory is in use\n");
 172                         goto disable;
 173                 }
 174         }
 175
 176         crashk_res.end = crashk_res.start + crash_size - 1;
 177
 178         /*
 179          * Crash kernel trumps memory limit
 180          */
 181         if ((memblock_end_of_DRAM() - memory_limit) <= crashk_res.end) {
 182                 memory_limit = 0;
 183                 pr_info("Disabled memory limit for crashkernel\n");
 184         }
 185
 186         pr_info("Reserving %ldMB of memory at 0x%08lx "
 187                 "for crashkernel (System RAM: %ldMB)\n",
 188                 (unsigned long)(crash_size >> 20),
 189                 (unsigned long)(crashk_res.start),
 190                 (unsigned long)(memblock_phys_mem_size() >> 20));
 191
 192         return;
 193
 194 disable:
 195         crashk_res.start = crashk_res.end = 0;
 196 }