openwrt/target/linux/image/aruba/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 #define LOADADDR 0x80100000
  39
  40 #define KSEG0                   0x80000000
  41 #define KSEG1                   0xa0000000
  42
  43 #define KSEG1ADDR(a)            ((((unsigned)(a)) & 0x1fffffffU) | KSEG1)
  44
  45 #define Index_Invalidate_I      0x00
  46 #define Index_Writeback_Inv_D   0x01
  47
  48 #define cache_unroll(base,op)   \
  49         __asm__ __volatile__(           \
  50                 ".set noreorder;\n"             \
  51                 ".set mips3;\n"                 \
  52                 "cache %1, (%0);\n"             \
  53                 ".set mips0;\n"                 \
  54                 ".set reorder\n"                \
  55                 :                                               \
  56                 : "r" (base),                   \
  57                   "i" (op));
  58
  59
  60 static __inline__ void blast_icache(unsigned long size, unsigned long lsize)
  61 {
  62         unsigned long start = KSEG0;
  63         unsigned long end = (start + size);
  64
  65         while(start < end) {
  66                 cache_unroll(start,Index_Invalidate_I);
  67                 start += lsize;
  68         }
  69 }
  70
  71 static __inline__ void blast_dcache(unsigned long size, unsigned long lsize)
  72 {
  73         unsigned long start = KSEG0;
  74         unsigned long end = (start + size);
  75
  76         while(start < end) {
  77                 cache_unroll(start,Index_Writeback_Inv_D);
  78                 start += lsize;
  79         }
  80 }
  81
  82 unsigned char *data;
  83
  84 static int read_byte(void *object, unsigned char **buffer, UInt32 *bufferSize)
  85 {
  86         *bufferSize = 1;
  87         *buffer = data;
  88         ++data;
  89         return LZMA_RESULT_OK;
  90 }
  91
  92 static __inline__ unsigned char get_byte(void)
  93 {
  94         unsigned char *buffer;
  95         UInt32 fake;
  96
  97         return read_byte(0, &buffer, &fake), *buffer;
  98 }
  99
 100 static char *buffer = (char *)0x80C00000;
 101 extern char lzma_start[];
 102 extern char lzma_end[];
 103
 104 /* should be the first function */
 105 void entry(unsigned long icache_size, unsigned long icache_lsize,
 106         unsigned long dcache_size, unsigned long dcache_lsize)
 107 {
 108         unsigned int i;  /* temp value */
 109         unsigned int osize; /* uncompressed size */
 110
 111         ILzmaInCallback callback;
 112         CLzmaDecoderState vs;
 113         callback.Read = read_byte;
 114
 115         data = lzma_start;
 116
 117         /* lzma args */
 118         i = get_byte();
 119         vs.Properties.lc = i % 9, i = i / 9;
 120         vs.Properties.lp = i % 5, vs.Properties.pb = i / 5;
 121
 122         vs.Probs = (CProb *)buffer;
 123
 124         /* skip rest of the LZMA coder property */
 125         for (i = 0; i < 4; i++)
 126                 get_byte();
 127
 128         /* read the lower half of uncompressed size in the header */
 129         osize = ((unsigned int)get_byte()) +
 130                 ((unsigned int)get_byte() << 8) +
 131                 ((unsigned int)get_byte() << 16) +
 132                 ((unsigned int)get_byte() << 24);
 133
 134         /* skip rest of the header (upper half of uncompressed size) */
 135         for (i = 0; i < 4; i++)
 136                 get_byte();
 137
 138         /* decompress kernel */
 139         if ((i = LzmaDecode(&vs, &callback,
 140         (unsigned char*)LOADADDR, osize, &osize)) == LZMA_RESULT_OK)
 141         {
 142                 blast_dcache(dcache_size, dcache_lsize);
 143                 blast_icache(icache_size, icache_lsize);
 144
 145                 /* Jump to load address */
 146                 ((void (*)(void)) LOADADDR)();
 147         }
 148 }