LXR linux/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#include <linux/libfdt.h>
  18
  19#include <asm/addrspace.h>
  20
  21/*
  22 * These two variables specify the free mem region
  23 * that can be used for temporary malloc area
  24 */
  25unsigned long free_mem_ptr;
  26unsigned long free_mem_end_ptr;
  27
  28/* The linker tells us where the image is. */
  29extern unsigned char __image_begin, __image_end;
  30
  31/* debug interfaces  */
  32#ifdef CONFIG_DEBUG_ZBOOT
  33extern void puts(const char *s);
  34extern void puthex(unsigned long long val);
  35#else
  36#define puts(s) do {} while (0)
  37#define puthex(val) do {} while (0)
  38#endif
  39
  40extern char __appended_dtb[];
  41
  42void error(char *x)
  43{
  44        puts("\n\n");
  45        puts(x);
  46        puts("\n\n -- System halted");
  47
  48        while (1)
  49                ;       /* Halt */
  50}
  51
  52/* activate the code for pre-boot environment */
  53#define STATIC static
  54
  55#ifdef CONFIG_KERNEL_GZIP
  56#include "../../../../lib/decompress_inflate.c"
  57#endif
  58
  59#ifdef CONFIG_KERNEL_BZIP2
  60#include "../../../../lib/decompress_bunzip2.c"
  61#endif
  62
  63#ifdef CONFIG_KERNEL_LZ4
  64#include "../../../../lib/decompress_unlz4.c"
  65#endif
  66
  67#ifdef CONFIG_KERNEL_LZMA
  68#include "../../../../lib/decompress_unlzma.c"
  69#endif
  70
  71#ifdef CONFIG_KERNEL_LZO
  72#include "../../../../lib/decompress_unlzo.c"
  73#endif
  74
  75#ifdef CONFIG_KERNEL_XZ
  76#include "../../../../lib/decompress_unxz.c"
  77#endif
  78
  79const unsigned long __stack_chk_guard = 0x000a0dff;
  80
  81void __stack_chk_fail(void)
  82{
  83        error("stack-protector: Kernel stack is corrupted\n");
  84}
  85
  86void decompress_kernel(unsigned long boot_heap_start)
  87{
  88        unsigned long zimage_start, zimage_size;
  89
  90        zimage_start = (unsigned long)(&__image_begin);
  91        zimage_size = (unsigned long)(&__image_end) -
  92            (unsigned long)(&__image_begin);
  93
  94        puts("zimage at:     ");
  95        puthex(zimage_start);
  96        puts(" ");
  97        puthex(zimage_size + zimage_start);
  98        puts("\n");
  99
 100        /* This area are prepared for mallocing when decompressing */
 101        free_mem_ptr = boot_heap_start;
 102        free_mem_end_ptr = boot_heap_start + BOOT_HEAP_SIZE;
 103
 104        /* Display standard Linux/MIPS boot prompt */
 105        puts("Uncompressing Linux at load address ");
 106        puthex(VMLINUX_LOAD_ADDRESS_ULL);
 107        puts("\n");
 108
 109        /* Decompress the kernel with according algorithm */
 110        __decompress((char *)zimage_start, zimage_size, 0, 0,
 111                   (void *)VMLINUX_LOAD_ADDRESS_ULL, 0, 0, error);
 112
 113        if (IS_ENABLED(CONFIG_MIPS_RAW_APPENDED_DTB) &&
 114            fdt_magic((void *)&__appended_dtb) == FDT_MAGIC) {
 115                unsigned int image_size, dtb_size;
 116
 117                dtb_size = fdt_totalsize((void *)&__appended_dtb);
 118
 119                /* last four bytes is always image size in little endian */
 120                image_size = le32_to_cpup((void *)&__image_end - 4);
 121
 122                /* copy dtb to where the booted kernel will expect it */
 123                memcpy((void *)VMLINUX_LOAD_ADDRESS_ULL + image_size,
 124                       __appended_dtb, dtb_size);
 125        }
 126
 127        /* FIXME: should we flush cache here? */
 128        puts("Now, booting the kernel...\n");
 129}
 130