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/pgtable.h>
  18 #include <asm/pgalloc.h>
  19 #include <asm/mmu_context.h>
  20 #include <asm/io.h>
  21 #include <asm/cacheflush.h>
  22 #include <asm/sh_bios.h>
  23 #include <asm/reboot.h>
  24
  25 typedef void (*relocate_new_kernel_t)(unsigned long indirection_page,
  26                                       unsigned long reboot_code_buffer,
  27                                       unsigned long start_address);
  28
  29 extern const unsigned char relocate_new_kernel[];
  30 extern const unsigned int relocate_new_kernel_size;
  31 extern void *vbr_base;
  32
  33 void native_machine_crash_shutdown(struct pt_regs *regs)
  34 {
  35         /* Nothing to do for UP, but definitely broken for SMP.. */
  36 }
  37
  38 /*
  39  * Do what every setup is needed on image and the
  40  * reboot code buffer to allow us to avoid allocations
  41  * later.
  42  */
  43 int machine_kexec_prepare(struct kimage *image)
  44 {
  45         return 0;
  46 }
  47
  48 void machine_kexec_cleanup(struct kimage *image)
  49 {
  50 }
  51
  52 static void kexec_info(struct kimage *image)
  53 {
  54         int i;
  55         printk("kexec information\n");
  56         for (i = 0; i < image->nr_segments; i++) {
  57                 printk("  segment[%d]: 0x%08x - 0x%08x (0x%08x)\n",
  58                        i,
  59                        (unsigned int)image->segment[i].mem,
  60                        (unsigned int)image->segment[i].mem +
  61                                      image->segment[i].memsz,
  62                        (unsigned int)image->segment[i].memsz);
  63         }
  64         printk("  start     : 0x%08x\n\n", (unsigned int)image->start);
  65 }
  66
  67 /*
  68  * Do not allocate memory (or fail in any way) in machine_kexec().
  69  * We are past the point of no return, committed to rebooting now.
  70  */
  71 void machine_kexec(struct kimage *image)
  72 {
  73         unsigned long page_list;
  74         unsigned long reboot_code_buffer;
  75         relocate_new_kernel_t rnk;
  76         unsigned long entry;
  77         unsigned long *ptr;
  78         int save_ftrace_enabled;
  79
  80         /*
  81          * Nicked from the mips version of machine_kexec():
  82          * The generic kexec code builds a page list with physical
  83          * addresses. Use phys_to_virt() to convert them to virtual.
  84          */
  85         for (ptr = &image->head; (entry = *ptr) && !(entry & IND_DONE);
  86              ptr = (entry & IND_INDIRECTION) ?
  87                phys_to_virt(entry & PAGE_MASK) : ptr + 1) {
  88                 if (*ptr & IND_SOURCE || *ptr & IND_INDIRECTION ||
  89                     *ptr & IND_DESTINATION)
  90                         *ptr = (unsigned long) phys_to_virt(*ptr);
  91         }
  92
  93 #ifdef CONFIG_KEXEC_JUMP
  94         if (image->preserve_context)
  95                 save_processor_state();
  96 #endif
  97
  98         save_ftrace_enabled = __ftrace_enabled_save();
  99
 100         /* Interrupts aren't acceptable while we reboot */
 101         local_irq_disable();
 102
 103         page_list = image->head;
 104
 105         /* we need both effective and real address here */
 106         reboot_code_buffer =
 107                         (unsigned long)page_address(image->control_code_page);
 108
 109         /* copy our kernel relocation code to the control code page */
 110         memcpy((void *)reboot_code_buffer, relocate_new_kernel,
 111                                                 relocate_new_kernel_size);
 112
 113         kexec_info(image);
 114         flush_cache_all();
 115
 116         sh_bios_vbr_reload();
 117
 118         /* now call it */
 119         rnk = (relocate_new_kernel_t) reboot_code_buffer;
 120         (*rnk)(page_list, reboot_code_buffer,
 121                (unsigned long)phys_to_virt(image->start));
 122
 123 #ifdef CONFIG_KEXEC_JUMP
 124         asm volatile("ldc %0, vbr" : : "r" (&vbr_base) : "memory");
 125
 126         if (image->preserve_context)
 127                 restore_processor_state();
 128
 129         /* Convert page list back to physical addresses, what a mess. */
 130         for (ptr = &image->head; (entry = *ptr) && !(entry & IND_DONE);
 131              ptr = (*ptr & IND_INDIRECTION) ?
 132                phys_to_virt(*ptr & PAGE_MASK) : ptr + 1) {
 133                 if (*ptr & IND_SOURCE || *ptr & IND_INDIRECTION ||
 134                     *ptr & IND_DESTINATION)
 135                         *ptr = virt_to_phys(*ptr);
 136         }
 137 #endif
 138
 139         __ftrace_enabled_restore(save_ftrace_enabled);
 140 }
 141
 142 void arch_crash_save_vmcoreinfo(void)
 143 {
 144 #ifdef CONFIG_NUMA
 145         VMCOREINFO_SYMBOL(node_data);
 146         VMCOREINFO_LENGTH(node_data, MAX_NUMNODES);
 147 #endif
 148 #ifdef CONFIG_X2TLB
 149         VMCOREINFO_CONFIG(X2TLB);
 150 #endif
 151 }
 152
 153 void __init reserve_crashkernel(void)
 154 {
 155         unsigned long long crash_size, crash_base;
 156         int ret;
 157
 158         ret = parse_crashkernel(boot_command_line, memblock_phys_mem_size(),
 159                         &crash_size, &crash_base);
 160         if (ret == 0 && crash_size > 0) {
 161                 crashk_res.start = crash_base;
 162                 crashk_res.end = crash_base + crash_size - 1;
 163         }
 164
 165         if (crashk_res.end == crashk_res.start)
 166                 goto disable;
 167
 168         crash_size = PAGE_ALIGN(resource_size(&crashk_res));
 169         if (!crashk_res.start) {
 170                 unsigned long max = memblock_end_of_DRAM() - memory_limit;
 171                 crashk_res.start = memblock_phys_alloc_range(crash_size,
 172                                                              PAGE_SIZE, 0, max);
 173                 if (!crashk_res.start) {
 174                         pr_err("crashkernel allocation failed\n");
 175                         goto disable;
 176                 }
 177         } else {
 178                 ret = memblock_reserve(crashk_res.start, crash_size);
 179                 if (unlikely(ret < 0)) {
 180                         pr_err("crashkernel reservation failed - "
 181                                "memory is in use\n");
 182                         goto disable;
 183                 }
 184         }
 185
 186         crashk_res.end = crashk_res.start + crash_size - 1;
 187
 188         /*
 189          * Crash kernel trumps memory limit
 190          */
 191         if ((memblock_end_of_DRAM() - memory_limit) <= crashk_res.end) {
 192                 memory_limit = 0;
 193                 pr_info("Disabled memory limit for crashkernel\n");
 194         }
 195
 196         pr_info("Reserving %ldMB of memory at 0x%08lx "
 197                 "for crashkernel (System RAM: %ldMB)\n",
 198                 (unsigned long)(crash_size >> 20),
 199                 (unsigned long)(crashk_res.start),
 200                 (unsigned long)(memblock_phys_mem_size() >> 20));
 201
 202         return;
 203
 204 disable:
 205         crashk_res.start = crashk_res.end = 0;
 206 }