target/linux/adm5120-2.6/image/lzma-loader/src/decompress.c

   1 /*
   2  * $Id$
   3  *
   4  * LZMA compressed kernel decompressor for ADM5120 boards
   5  *
   6  * Copyright (C) 2005 by Oleg I. Vdovikin <oleg@cs.msu.su>
   7  * Copyright (C) 2007 OpenWrt.org
   8  *
   9  * This program is free software; you can redistribute it and/or modify
  10  * it under the terms of the GNU General Public License as published by
  11  * the Free Software Foundation; either version 2 of the License, or
  12  * (at your option) any later version.
  13  *
  14  * This program is distributed in the hope that it will be useful,
  15  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  16  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
  17  * General Public License for more details.
  18  *
  19  * You should have received a copy of the GNU General Public License
  20  * along with this program; if not, write to the Free Software
  21  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
  22  *
  23  *
  24  * Please note, this was code based on the bunzip2 decompressor code
  25  * by Manuel Novoa III  (mjn3@codepoet.org), although the only thing left
  26  * is an idea and part of original vendor code
  27  *
  28  *
  29  * 12-Mar-2005  Mineharu Takahara <mtakahar@yahoo.com>
  30  *   pass actual output size to decoder (stream mode
  31  *   compressed input is not a requirement anymore)
  32  *
  33  * 24-Apr-2005 Oleg I. Vdovikin
  34  *   reordered functions using lds script, removed forward decl
  35  *
  36  * 24-Mar-2007 Gabor Juhos
  37  *   pass original values of the a0,a1,a2,a3 registers to the kernel
  38  *
  39  * 19-May-2007 Gabor Juhos
  40  *   endiannes related cleanups
  41  *   add support for decompressing an embedded kernel
  42  *
  43  */
  44
  45 #include <stddef.h>
  46
  47 #include "config.h"
  48 #include "printf.h"
  49 #include "LzmaDecode.h"
  50
  51 #define ADM5120_FLASH_START     0x1fc00000      /* Flash start */
  52 #define ADM5120_FLASH_END       0x1fe00000      /* Flash end */
  53
  54 #define KSEG0                   0x80000000
  55 #define KSEG1                   0xa0000000
  56
  57 #define KSEG1ADDR(a)            ((((unsigned)(a)) & 0x1fffffffU) | KSEG1)
  58
  59 #define Index_Invalidate_I      0x00
  60 #define Index_Writeback_Inv_D   0x01
  61
  62 #define cache_unroll(base,op)   \
  63         __asm__ __volatile__(           \
  64                 ".set noreorder;\n"             \
  65                 ".set mips3;\n"                 \
  66                 "cache %1, (%0);\n"             \
  67                 ".set mips0;\n"                 \
  68                 ".set reorder\n"                \
  69                 :                               \
  70                 : "r" (base),                   \
  71                   "i" (op));
  72
  73 #ifdef LZMA_DEBUG
  74 #  define DBG(f, a...)  printf(f, ## a)
  75 #else
  76 #  define DBG(f, a...)  do {} while (0)
  77 #endif
  78
  79 static __inline__ void blast_icache(unsigned long size, unsigned long lsize)
  80 {
  81         unsigned long start = KSEG0;
  82         unsigned long end = (start + size);
  83
  84         while(start < end) {
  85                 cache_unroll(start,Index_Invalidate_I);
  86                 start += lsize;
  87         }
  88 }
  89
  90 static __inline__ void blast_dcache(unsigned long size, unsigned long lsize)
  91 {
  92         unsigned long start = KSEG0;
  93         unsigned long end = (start + size);
  94
  95         while(start < end) {
  96                 cache_unroll(start,Index_Writeback_Inv_D);
  97                 start += lsize;
  98         }
  99 }
 100
 101 #define TRX_MAGIC       0x30524448      /* "HDR0" */
 102 #define TRX_ALIGN       0x1000
 103
 104 struct trx_header {
 105         unsigned int magic;             /* "HDR0" */
 106         unsigned int len;               /* Length of file including header */
 107         unsigned int crc32;             /* 32-bit CRC from flag_version to end of file */
 108         unsigned int flag_version;      /* 0:15 flags, 16:31 version */
 109         unsigned int offsets[3];        /* Offsets of partitions from start of header */
 110 };
 111
 112 struct env_var {
 113         char    *name;
 114         char    *value;
 115 };
 116
 117 /* beyound the image end, size not known in advance */
 118 extern unsigned char workspace[];
 119 extern void board_init(void);
 120
 121 typedef void (*kernel_entry)(unsigned long reg_a0, unsigned long reg_a1,
 122         unsigned long reg_a2, unsigned long reg_a3);
 123
 124 static int decompress_data(unsigned char *buffer, UInt32 bufferSize,
 125         int lc, int lp, int pb, unsigned char *outStream, UInt32 outSize,
 126         UInt32 *outSizeProcessed);
 127
 128 #ifdef CONFIG_PASS_KARGS
 129 #define ENVV(n,v)       {.name = (n), .value = (v)}
 130 struct env_var env_vars[] = {
 131         ENVV("board_name",      CONFIG_BOARD_NAME),
 132         ENVV(NULL, NULL)
 133 };
 134 #endif
 135
 136 static void halt(void)
 137 {
 138         printf("\nSystem halted!\n");
 139         for(;;);
 140 }
 141
 142 #if LZMA_WRAPPER
 143 extern unsigned char _lzma_data_start[];
 144 extern unsigned char _lzma_data_end[];
 145
 146 unsigned char *data;
 147 unsigned long datalen;
 148
 149 static __inline__ unsigned char get_byte(void)
 150 {
 151         datalen--;
 152         return *data++;
 153 }
 154
 155 static void decompress_init(void)
 156 {
 157         data = _lzma_data_start;
 158         datalen = _lzma_data_end - _lzma_data_start;
 159 }
 160
 161 static int decompress_data(unsigned char *buffer, UInt32 bufferSize,
 162         int lc, int lp, int pb, unsigned char *outStream, UInt32 outSize,
 163         UInt32 *outSizeProcessed)
 164 {
 165         return LzmaDecode(buffer, bufferSize, lc, lp, pb, data, datalen,
 166                 outStream, outSize, outSizeProcessed);
 167 }
 168 #endif /* LZMA_WRAPPER */
 169
 170 #if !(LZMA_WRAPPER)
 171
 172 #define FLASH_BANK_SIZE (2<<20)
 173
 174 static unsigned char *flash_base = (unsigned char *) KSEG1ADDR(ADM5120_FLASH_START);
 175 static unsigned long flash_ofs = 0;
 176 static unsigned long flash_max = 0;
 177 static unsigned long flash_ofs_mask = (FLASH_BANK_SIZE-1);
 178
 179 static __inline__ unsigned char get_byte(void)
 180 {
 181         return *(flash_base+flash_ofs++);
 182 }
 183
 184 static int lzma_read_byte(void *object, unsigned char **buffer, UInt32 *bufferSize)
 185 {
 186         unsigned long len;
 187
 188         if (flash_ofs >= flash_max)
 189                 return LZMA_RESULT_DATA_ERROR;
 190
 191         len = flash_max-flash_ofs;
 192
 193 #if (CONFIG_FLASH_SIZE > FLASH_BANK_SIZE)
 194         if (flash_ofs < FLASH_BANK_SIZE) {
 195                 /* switch to bank 0 */
 196                 DBG("lzma_read_byte: switch to bank 0\n");
 197
 198                 if (len > FLASH_BANK_SIZE-flash_ofs)
 199                         len = FLASH_BANK_SIZE-flash_ofs;
 200         } else {
 201                 /* switch to bank 1 */
 202                 DBG("lzma_read_byte: switch to bank 1\n");
 203         }
 204 #endif
 205         DBG("lzma_read_byte: ofs=%08X, len=%08X\n", flash_ofs, len);
 206
 207         *buffer = flash_base+(flash_ofs & flash_ofs_mask);
 208         *bufferSize = len;
 209         flash_ofs += len;
 210
 211         return LZMA_RESULT_OK;
 212 }
 213
 214 static ILzmaInCallback lzma_callback = {
 215         .Read   = lzma_read_byte,
 216 };
 217
 218 static __inline__ unsigned int read_le32(void *buf)
 219 {
 220         unsigned char *p = buf;
 221
 222         return ((unsigned int)p[0] + ((unsigned int)p[1] << 8) +
 223                 ((unsigned int)p[2] << 16) +((unsigned int)p[3] << 24));
 224 }
 225
 226 static void decompress_init(void)
 227 {
 228         struct trx_header *hdr = NULL;
 229         unsigned long kofs,klen;
 230
 231         printf("Looking for TRX header... ");
 232         /* look for trx header, 32-bit data access */
 233         for (flash_ofs = 0; flash_ofs < FLASH_BANK_SIZE; flash_ofs += TRX_ALIGN) {
 234                 if (read_le32(&flash_base[flash_ofs]) == TRX_MAGIC) {
 235                         hdr = (struct trx_header *)&flash_base[flash_ofs];
 236                         break;
 237                 }
 238         }
 239
 240         if (hdr == NULL) {
 241                 printf("not found!\n");
 242                 /* no compressed kernel found, halting */
 243                 halt();
 244         }
 245
 246         /* compressed kernel is in the partition 0 or 1 */
 247         kofs = read_le32(&hdr->offsets[1]);
 248         if (kofs == 0 || kofs > 65536) {
 249                 klen = kofs-read_le32(&hdr->offsets[0]);
 250                 kofs = read_le32(&hdr->offsets[0]);
 251         } else {
 252                 klen = read_le32(&hdr->offsets[2]);
 253                 if (klen > kofs)
 254                         klen -= kofs;
 255                 else
 256                         klen = read_le32(&hdr->len)-kofs;
 257         }
 258
 259         printf("found at %08X, kernel:%08X len:%08X\n", flash_ofs,
 260                 kofs, klen);
 261
 262         flash_ofs += kofs;
 263         flash_max = flash_ofs+klen;
 264 }
 265
 266 static int decompress_data(unsigned char *buffer, UInt32 bufferSize,
 267         int lc, int lp, int pb, unsigned char *outStream, UInt32 outSize,
 268         UInt32 *outSizeProcessed)
 269 {
 270         return LzmaDecode(buffer, bufferSize, lc, lp, pb, &lzma_callback,
 271                 outStream, outSize, outSizeProcessed);
 272 }
 273 #endif /* !(LZMA_WRAPPER) */
 274
 275 /* should be the first function */
 276 void decompress_entry(unsigned long reg_a0, unsigned long reg_a1,
 277         unsigned long reg_a2, unsigned long reg_a3,
 278         unsigned long icache_size, unsigned long icache_lsize,
 279         unsigned long dcache_size, unsigned long dcache_lsize)
 280 {
 281         unsigned int i;  /* temp value */
 282         unsigned int lc; /* literal context bits */
 283         unsigned int lp; /* literal pos state bits */
 284         unsigned int pb; /* pos state bits */
 285         unsigned int osize; /* uncompressed size */
 286         int res;
 287
 288         board_init();
 289
 290         printf("\n\nLZMA loader for " CONFIG_BOARD_NAME
 291                         ", Copyright (C) 2007 OpenWrt.org\n\n");
 292
 293         decompress_init();
 294
 295         /* lzma args */
 296         i = get_byte();
 297         lc = i % 9, i = i / 9;
 298         lp = i % 5, pb = i / 5;
 299
 300         /* skip rest of the LZMA coder property */
 301         for (i = 0; i < 4; i++)
 302                 get_byte();
 303
 304         /* read the lower half of uncompressed size in the header */
 305         osize = ((unsigned int)get_byte()) +
 306                 ((unsigned int)get_byte() << 8) +
 307                 ((unsigned int)get_byte() << 16) +
 308                 ((unsigned int)get_byte() << 24);
 309
 310         /* skip rest of the header (upper half of uncompressed size) */
 311         for (i = 0; i < 4; i++)
 312                 get_byte();
 313
 314         printf("decompressing kernel... ");
 315
 316         /* decompress kernel */
 317         res = decompress_data(workspace, ~0, lc, lp, pb,
 318                 (unsigned char *)LOADADDR, osize, &i);
 319
 320         if (res != LZMA_RESULT_OK) {
 321                 printf("failed, ");
 322                 switch (res) {
 323                 case LZMA_RESULT_DATA_ERROR:
 324                         printf("data error!\n");
 325                         break;
 326                 case LZMA_RESULT_NOT_ENOUGH_MEM:
 327                         printf("not enough memory!\n");
 328                         break;
 329                 default:
 330                         printf("unknown error %d!\n", res);
 331                 }
 332                 halt();
 333         } else
 334                 printf("done!\n");
 335
 336         blast_dcache(dcache_size, dcache_lsize);
 337         blast_icache(icache_size, icache_lsize);
 338
 339         printf("launching kernel...\n\n");
 340
 341 #ifdef CONFIG_PASS_KARGS
 342         reg_a0 = 0;
 343         reg_a1 = 0;
 344         reg_a2 = (unsigned long)env_vars;
 345         reg_a3 = 0;
 346 #endif
 347         /* Jump to load address */
 348         ((kernel_entry) LOADADDR)(reg_a0, reg_a1, reg_a2, reg_a3);
 349 }