target/linux/adm8668/image/lzma-loader/src/decompress.c

   1 /*
   2  * LZMA compressed kernel decompressor for bcm947xx boards
   3  *
   4  * Copyright (C) 2005 by Oleg I. Vdovikin <oleg@cs.msu.su>
   5  *
   6  * This program is free software; you can redistribute it and/or modify
   7  * it under the terms of the GNU General Public License as published by
   8  * the Free Software Foundation; either version 2 of the License, or
   9  * (at your option) any later version.
  10  *
  11  * This program is distributed in the hope that it will be useful,
  12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
  14  * General Public License for more details.
  15  *
  16  * You should have received a copy of the GNU General Public License
  17  * along with this program; if not, write to the Free Software
  18  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
  19  *
  20  *
  21  * Please note, this was code based on the bunzip2 decompressor code
  22  * by Manuel Novoa III  (mjn3@codepoet.org), although the only thing left
  23  * is an idea and part of original vendor code
  24  *
  25  *
  26  * 12-Mar-2005  Mineharu Takahara <mtakahar@yahoo.com>
  27  *   pass actual output size to decoder (stream mode
  28  *   compressed input is not a requirement anymore)
  29  *
  30  * 24-Apr-2005 Oleg I. Vdovikin
  31  *   reordered functions using lds script, removed forward decl
  32  *
  33  * ??-Nov-2005 Mike Baker
  34  *   reorder the script as an lzma wrapper; do not depend on flash access
  35  */
  36
  37 #include "LzmaDecode.h"
  38 #include <exports.h>
  39
  40 #define KSEG0ADDR(addr) (0x80000000|addr)
  41
  42 register volatile gd_t *gd asm ("k0");
  43 unsigned char *data;
  44
  45 static __inline__ unsigned char get_byte()
  46 {
  47         unsigned char *buffer;
  48
  49         buffer = data;
  50         data++;
  51
  52         return *buffer;
  53 }
  54
  55 /* This puts lzma workspace 128k below RAM end.
  56  * That should be enough for both lzma and stack
  57  */
  58 static char *buffer = (char *)(RAMSTART + RAMSIZE - 0x00020000);
  59 extern char _binary_vmlinux_lzma_start[];
  60 extern char _binary_vmlinux_lzma_end[];
  61 extern char lzma_start[];
  62 extern char lzma_end[];
  63
  64 /* should be the first function */
  65 void entry(unsigned int arg0, unsigned int arg1,
  66         unsigned int arg2, unsigned int arg3)
  67 {
  68         unsigned int i;  /* temp value */
  69         unsigned int isize; /* compressed size */
  70         unsigned int osize; /* uncompressed size */
  71         int argc = arg0;
  72         char **argv = (char **)arg1;
  73         char **envp = (char **)arg2;
  74
  75         CLzmaDecoderState vs;
  76
  77         data = (unsigned char *)_binary_vmlinux_lzma_start;
  78         isize = _binary_vmlinux_lzma_end - _binary_vmlinux_lzma_start + 1;
  79
  80         puts("\nLZMA kernel loader\n");
  81
  82         printf("lzma data @ %#x - %#x\n", _binary_vmlinux_lzma_start, _binary_vmlinux_lzma_end);
  83         printf("load addr @ %#x\n\n", KERNEL_ENTRY);
  84         printf("jump table @ %#x\n", gd->jt[3]);
  85
  86         /* lzma args */
  87         i = get_byte();
  88         vs.Properties.lc = i % 9, i = i / 9;
  89         vs.Properties.lp = i % 5, vs.Properties.pb = i / 5;
  90
  91         vs.Probs = (CProb *)buffer;
  92
  93         /* skip rest of the LZMA coder property */
  94         data += 4;
  95
  96         /* read the lower half of uncompressed size in the header */
  97         osize = ((unsigned int)get_byte()) +
  98                 ((unsigned int)get_byte() << 8) +
  99                 ((unsigned int)get_byte() << 16) +
 100                 ((unsigned int)get_byte() << 24);
 101
 102         /* skip rest of the header (upper half of uncompressed size) */
 103         data += 4;
 104
 105         /* decompress kernel */
 106         puts("\nDecompressing kernel...");
 107         if ((i = LzmaDecode(&vs,
 108         (unsigned char*)data, isize, &isize,
 109         (unsigned char*)KERNEL_ENTRY, osize, &osize)) == LZMA_RESULT_OK)
 110         {
 111                 puts("success!\n");
 112
 113                 /* Jump to load address */
 114 //              ((void (*)(int a0, int a1, int a2, int a3))KERNEL_ENTRY)(0,0,0,0);
 115                 ((void (*)(int a0, int a1, int a2, int a3))KERNEL_ENTRY)(arg0, arg1, arg2, arg3);
 116         }
 117         puts("failure!\n");
 118 }