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 #ifdef CONFIG_DEBUG_ZBOOT
  32 extern void puts(const char *s);
  33 extern void puthex(unsigned long long val);
  34 #else
  35 #define puts(s) do {} while (0)
  36 #define puthex(val) do {} while (0)
  37 #endif
  38
  39 void error(char *x)
  40 {
  41         puts("\n\n");
  42         puts(x);
  43         puts("\n\n -- System halted");
  44
  45         while (1)
  46                 ;       /* Halt */
  47 }
  48
  49 /* activate the code for pre-boot environment */
  50 #define STATIC static
  51
  52 #ifdef CONFIG_KERNEL_GZIP
  53 #include "../../../../lib/decompress_inflate.c"
  54 #endif
  55
  56 #ifdef CONFIG_KERNEL_BZIP2
  57 #include "../../../../lib/decompress_bunzip2.c"
  58 #endif
  59
  60 #ifdef CONFIG_KERNEL_LZ4
  61 #include "../../../../lib/decompress_unlz4.c"
  62 #endif
  63
  64 #ifdef CONFIG_KERNEL_LZMA
  65 #include "../../../../lib/decompress_unlzma.c"
  66 #endif
  67
  68 #ifdef CONFIG_KERNEL_LZO
  69 #include "../../../../lib/decompress_unlzo.c"
  70 #endif
  71
  72 #ifdef CONFIG_KERNEL_XZ
  73 #include "../../../../lib/decompress_unxz.c"
  74 #endif
  75
  76 unsigned long __stack_chk_guard;
  77
  78 void __stack_chk_guard_setup(void)
  79 {
  80         __stack_chk_guard = 0x000a0dff;
  81 }
  82
  83 void __stack_chk_fail(void)
  84 {
  85         error("stack-protector: Kernel stack is corrupted\n");
  86 }
  87
  88 void decompress_kernel(unsigned long boot_heap_start)
  89 {
  90         unsigned long zimage_start, zimage_size;
  91
  92         __stack_chk_guard_setup();
  93
  94         zimage_start = (unsigned long)(&__image_begin);
  95         zimage_size = (unsigned long)(&__image_end) -
  96             (unsigned long)(&__image_begin);
  97
  98         puts("zimage at:     ");
  99         puthex(zimage_start);
 100         puts(" ");
 101         puthex(zimage_size + zimage_start);
 102         puts("\n");
 103
 104         /* This area are prepared for mallocing when decompressing */
 105         free_mem_ptr = boot_heap_start;
 106         free_mem_end_ptr = boot_heap_start + BOOT_HEAP_SIZE;
 107
 108         /* Display standard Linux/MIPS boot prompt */
 109         puts("Uncompressing Linux at load address ");
 110         puthex(VMLINUX_LOAD_ADDRESS_ULL);
 111         puts("\n");
 112
 113         /* Decompress the kernel with according algorithm */
 114         __decompress((char *)zimage_start, zimage_size, 0, 0,
 115                    (void *)VMLINUX_LOAD_ADDRESS_ULL, 0, 0, error);
 116
 117         /* FIXME: should we flush cache here? */
 118         puts("Now, booting the kernel...\n");
 119 }