arch/sh/kernel/machine_kexec.c

   1 /*
   2  * machine_kexec.c - handle transition of Linux booting another kernel
   3  * Copyright (C) 2002-2003 Eric Biederman  <ebiederm@xmission.com>
   4  *
   5  * GameCube/ppc32 port Copyright (C) 2004 Albert Herranz
   6  * LANDISK/sh4 supported by kogiidena
   7  *
   8  * This source code is licensed under the GNU General Public License,
   9  * Version 2.  See the file COPYING for more details.
  10  */
  11
  12 #include <linux/mm.h>
  13 #include <linux/kexec.h>
  14 #include <linux/delay.h>
  15 #include <linux/reboot.h>
  16 #include <linux/numa.h>
  17 #include <linux/ftrace.h>
  18 #include <linux/suspend.h>
  19 #include <asm/pgtable.h>
  20 #include <asm/pgalloc.h>
  21 #include <asm/mmu_context.h>
  22 #include <asm/io.h>
  23 #include <asm/cacheflush.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 *gdb_vbr_vector;
  32 extern void *vbr_base;
  33
  34 void machine_shutdown(void)
  35 {
  36 }
  37
  38 void machine_crash_shutdown(struct pt_regs *regs)
  39 {
  40 }
  41
  42 /*
  43  * Do what every setup is needed on image and the
  44  * reboot code buffer to allow us to avoid allocations
  45  * later.
  46  */
  47 int machine_kexec_prepare(struct kimage *image)
  48 {
  49         return 0;
  50 }
  51
  52 void machine_kexec_cleanup(struct kimage *image)
  53 {
  54 }
  55
  56 static void kexec_info(struct kimage *image)
  57 {
  58         int i;
  59         printk("kexec information\n");
  60         for (i = 0; i < image->nr_segments; i++) {
  61                 printk("  segment[%d]: 0x%08x - 0x%08x (0x%08x)\n",
  62                        i,
  63                        (unsigned int)image->segment[i].mem,
  64                        (unsigned int)image->segment[i].mem +
  65                                      image->segment[i].memsz,
  66                        (unsigned int)image->segment[i].memsz);
  67         }
  68         printk("  start     : 0x%08x\n\n", (unsigned int)image->start);
  69 }
  70
  71 /*
  72  * Do not allocate memory (or fail in any way) in machine_kexec().
  73  * We are past the point of no return, committed to rebooting now.
  74  */
  75 void machine_kexec(struct kimage *image)
  76 {
  77         unsigned long page_list;
  78         unsigned long reboot_code_buffer;
  79         relocate_new_kernel_t rnk;
  80         unsigned long entry;
  81         unsigned long *ptr;
  82         int save_ftrace_enabled;
  83
  84         /*
  85          * Nicked from the mips version of machine_kexec():
  86          * The generic kexec code builds a page list with physical
  87          * addresses. Use phys_to_virt() to convert them to virtual.
  88          */
  89         for (ptr = &image->head; (entry = *ptr) && !(entry & IND_DONE);
  90              ptr = (entry & IND_INDIRECTION) ?
  91                phys_to_virt(entry & PAGE_MASK) : ptr + 1) {
  92                 if (*ptr & IND_SOURCE || *ptr & IND_INDIRECTION ||
  93                     *ptr & IND_DESTINATION)
  94                         *ptr = (unsigned long) phys_to_virt(*ptr);
  95         }
  96
  97 #ifdef CONFIG_KEXEC_JUMP
  98         if (image->preserve_context)
  99                 save_processor_state();
 100 #endif
 101
 102         save_ftrace_enabled = __ftrace_enabled_save();
 103
 104         /* Interrupts aren't acceptable while we reboot */
 105         local_irq_disable();
 106
 107         page_list = image->head;
 108
 109         /* we need both effective and real address here */
 110         reboot_code_buffer =
 111                         (unsigned long)page_address(image->control_code_page);
 112
 113         /* copy our kernel relocation code to the control code page */
 114         memcpy((void *)reboot_code_buffer, relocate_new_kernel,
 115                                                 relocate_new_kernel_size);
 116
 117         kexec_info(image);
 118         flush_cache_all();
 119
 120 #if defined(CONFIG_SH_STANDARD_BIOS)
 121         asm volatile("ldc %0, vbr" :
 122                      : "r" (((unsigned long) gdb_vbr_vector) - 0x100)
 123                      : "memory");
 124 #endif
 125
 126         /* now call it */
 127         rnk = (relocate_new_kernel_t) reboot_code_buffer;
 128         (*rnk)(page_list, reboot_code_buffer,
 129                (unsigned long)phys_to_virt(image->start));
 130
 131 #ifdef CONFIG_KEXEC_JUMP
 132         asm volatile("ldc %0, vbr" : : "r" (&vbr_base) : "memory");
 133
 134         if (image->preserve_context)
 135                 restore_processor_state();
 136
 137         /* Convert page list back to physical addresses, what a mess. */
 138         for (ptr = &image->head; (entry = *ptr) && !(entry & IND_DONE);
 139              ptr = (*ptr & IND_INDIRECTION) ?
 140                phys_to_virt(*ptr & PAGE_MASK) : ptr + 1) {
 141                 if (*ptr & IND_SOURCE || *ptr & IND_INDIRECTION ||
 142                     *ptr & IND_DESTINATION)
 143                         *ptr = virt_to_phys(*ptr);
 144         }
 145 #endif
 146
 147         __ftrace_enabled_restore(save_ftrace_enabled);
 148 }
 149
 150 void arch_crash_save_vmcoreinfo(void)
 151 {
 152 #ifdef CONFIG_NUMA
 153         VMCOREINFO_SYMBOL(node_data);
 154         VMCOREINFO_LENGTH(node_data, MAX_NUMNODES);
 155 #endif
 156 }