arch/mips/boot/compressed/decompress.c

   1 /*
   2  * Copyright 2001 MontaVista Software Inc.
   3  * Author: Matt Porter <mporter@mvista.com>
   4  *
   5  * Copyright (C) 2009 Lemote, Inc.
   6  * Author: Wu Zhangjin <wuzhangjin@gmail.com>
   7  *
   8  * This program is free software; you can redistribute  it and/or modify it
   9  * under  the terms of  the GNU General  Public License as published by the
  10  * Free Software Foundation;  either version 2 of the  License, or (at your
  11  * option) any later version.
  12  */
  13
  14 #include <linux/types.h>
  15 #include <linux/kernel.h>
  16 #include <linux/string.h>
  17
  18 #include <asm/addrspace.h>
  19
  20 /*
  21  * These two variables specify the free mem region
  22  * that can be used for temporary malloc area
  23  */
  24 unsigned long free_mem_ptr;
  25 unsigned long free_mem_end_ptr;
  26
  27 /* The linker tells us where the image is. */
  28 extern unsigned char __image_begin, __image_end;
  29
  30 /* debug interfaces  */
  31 extern void puts(const char *s);
  32 extern void puthex(unsigned long long val);
  33
  34 void error(char *x)
  35 {
  36         puts("\n\n");
  37         puts(x);
  38         puts("\n\n -- System halted");
  39
  40         while (1)
  41                 ;       /* Halt */
  42 }
  43
  44 /* activate the code for pre-boot environment */
  45 #define STATIC static
  46
  47 #ifdef CONFIG_KERNEL_GZIP
  48 #include "../../../../lib/decompress_inflate.c"
  49 #endif
  50
  51 #ifdef CONFIG_KERNEL_BZIP2
  52 #include "../../../../lib/decompress_bunzip2.c"
  53 #endif
  54
  55 #ifdef CONFIG_KERNEL_LZ4
  56 #include "../../../../lib/decompress_unlz4.c"
  57 #endif
  58
  59 #ifdef CONFIG_KERNEL_LZMA
  60 #include "../../../../lib/decompress_unlzma.c"
  61 #endif
  62
  63 #ifdef CONFIG_KERNEL_LZO
  64 #include "../../../../lib/decompress_unlzo.c"
  65 #endif
  66
  67 #ifdef CONFIG_KERNEL_XZ
  68 #include "../../../../lib/decompress_unxz.c"
  69 #endif
  70
  71 unsigned long __stack_chk_guard;
  72
  73 void __stack_chk_guard_setup(void)
  74 {
  75         __stack_chk_guard = 0x000a0dff;
  76 }
  77
  78 void __stack_chk_fail(void)
  79 {
  80         error("stack-protector: Kernel stack is corrupted\n");
  81 }
  82
  83 void decompress_kernel(unsigned long boot_heap_start)
  84 {
  85         unsigned long zimage_start, zimage_size;
  86
  87         __stack_chk_guard_setup();
  88
  89         zimage_start = (unsigned long)(&__image_begin);
  90         zimage_size = (unsigned long)(&__image_end) -
  91             (unsigned long)(&__image_begin);
  92
  93         puts("zimage at:     ");
  94         puthex(zimage_start);
  95         puts(" ");
  96         puthex(zimage_size + zimage_start);
  97         puts("\n");
  98
  99         /* This area are prepared for mallocing when decompressing */
 100         free_mem_ptr = boot_heap_start;
 101         free_mem_end_ptr = boot_heap_start + BOOT_HEAP_SIZE;
 102
 103         /* Display standard Linux/MIPS boot prompt */
 104         puts("Uncompressing Linux at load address ");
 105         puthex(VMLINUX_LOAD_ADDRESS_ULL);
 106         puts("\n");
 107
 108         /* Decompress the kernel with according algorithm */
 109         decompress((char *)zimage_start, zimage_size, 0, 0,
 110                    (void *)VMLINUX_LOAD_ADDRESS_ULL, 0, error);
 111
 112         /* FIXME: should we flush cache here? */
 113         puts("Now, booting the kernel...\n");
 114 }