target/linux/ramips/image/lzma-loader/src/loader.c

   1 /*
   2  * LZMA compressed kernel loader for Atheros AR7XXX/AR9XXX based boards
   3  *
   4  * Copyright (C) 2011 Gabor Juhos <juhosg@openwrt.org>
   5  *
   6  * Some parts of this code was based on the OpenWrt specific lzma-loader
   7  * for the BCM47xx and ADM5120 based boards:
   8  *      Copyright (C) 2004 Manuel Novoa III (mjn3@codepoet.org)
   9  *      Copyright (C) 2005 Mineharu Takahara <mtakahar@yahoo.com>
  10  *      Copyright (C) 2005 by Oleg I. Vdovikin <oleg@cs.msu.su>
  11  *
  12  * The image_header structure has been taken from the U-Boot project.
  13  *      (C) Copyright 2008 Semihalf
  14  *      (C) Copyright 2000-2005
  15  *      Wolfgang Denk, DENX Software Engineering, wd@denx.de.
  16  *
  17  * This program is free software; you can redistribute it and/or modify it
  18  * under the terms of the GNU General Public License version 2 as published
  19  * by the Free Software Foundation.
  20  */
  21
  22 #include <stddef.h>
  23 #include <stdint.h>
  24
  25 #include "config.h"
  26 #include "cache.h"
  27 #include "printf.h"
  28 #include "LzmaDecode.h"
  29
  30 #define AR71XX_FLASH_START      0x1f000000
  31 #define AR71XX_FLASH_END        0x1fe00000
  32
  33 #define KSEG0                   0x80000000
  34 #define KSEG1                   0xa0000000
  35
  36 #define KSEG1ADDR(a)            ((((unsigned)(a)) & 0x1fffffffU) | KSEG1)
  37
  38 #undef LZMA_DEBUG
  39
  40 #ifdef LZMA_DEBUG
  41 #  define DBG(f, a...)  printf(f, ## a)
  42 #else
  43 #  define DBG(f, a...)  do {} while (0)
  44 #endif
  45
  46 #define IH_MAGIC_OKLI           0x4f4b4c49      /* 'OKLI' */
  47
  48 #define IH_NMLEN                32      /* Image Name Length            */
  49
  50 typedef struct image_header {
  51         uint32_t        ih_magic;       /* Image Header Magic Number    */
  52         uint32_t        ih_hcrc;        /* Image Header CRC Checksum    */
  53         uint32_t        ih_time;        /* Image Creation Timestamp     */
  54         uint32_t        ih_size;        /* Image Data Size              */
  55         uint32_t        ih_load;        /* Data  Load  Address          */
  56         uint32_t        ih_ep;          /* Entry Point Address          */
  57         uint32_t        ih_dcrc;        /* Image Data CRC Checksum      */
  58         uint8_t         ih_os;          /* Operating System             */
  59         uint8_t         ih_arch;        /* CPU architecture             */
  60         uint8_t         ih_type;        /* Image Type                   */
  61         uint8_t         ih_comp;        /* Compression Type             */
  62         uint8_t         ih_name[IH_NMLEN];      /* Image Name           */
  63 } image_header_t;
  64
  65 /* beyond the image end, size not known in advance */
  66 extern unsigned char workspace[];
  67 extern void board_init(void);
  68
  69 static CLzmaDecoderState lzma_state;
  70 static unsigned char *lzma_data;
  71 static unsigned long lzma_datasize;
  72 static unsigned long lzma_outsize;
  73 static unsigned long kernel_la;
  74
  75 #ifdef CONFIG_KERNEL_CMDLINE
  76 #define kernel_argc     1
  77 static const char kernel_cmdline[] = CONFIG_KERNEL_CMDLINE;
  78 static const char *kernel_argv[] = {
  79         kernel_cmdline,
  80         NULL,
  81 };
  82 #endif /* CONFIG_KERNEL_CMDLINE */
  83
  84 static void halt(void)
  85 {
  86         printf("\nSystem halted!\n");
  87         for(;;);
  88 }
  89
  90 static __inline__ unsigned long get_be32(void *buf)
  91 {
  92         unsigned char *p = buf;
  93
  94         return (((unsigned long) p[0] << 24) +
  95                 ((unsigned long) p[1] << 16) +
  96                 ((unsigned long) p[2] << 8) +
  97                 (unsigned long) p[3]);
  98 }
  99
 100 static __inline__ unsigned char lzma_get_byte(void)
 101 {
 102         unsigned char c;
 103
 104         lzma_datasize--;
 105         c = *lzma_data++;
 106
 107         return c;
 108 }
 109
 110 static int lzma_init_props(void)
 111 {
 112         unsigned char props[LZMA_PROPERTIES_SIZE];
 113         int res;
 114         int i;
 115
 116         /* read lzma properties */
 117         for (i = 0; i < LZMA_PROPERTIES_SIZE; i++)
 118                 props[i] = lzma_get_byte();
 119
 120         /* read the lower half of uncompressed size in the header */
 121         lzma_outsize = ((SizeT) lzma_get_byte()) +
 122                        ((SizeT) lzma_get_byte() << 8) +
 123                        ((SizeT) lzma_get_byte() << 16) +
 124                        ((SizeT) lzma_get_byte() << 24);
 125
 126         /* skip rest of the header (upper half of uncompressed size) */
 127         for (i = 0; i < 4; i++)
 128                 lzma_get_byte();
 129
 130         res = LzmaDecodeProperties(&lzma_state.Properties, props,
 131                                         LZMA_PROPERTIES_SIZE);
 132         return res;
 133 }
 134
 135 static int lzma_decompress(unsigned char *outStream)
 136 {
 137         SizeT ip, op;
 138         int ret;
 139
 140         lzma_state.Probs = (CProb *) workspace;
 141
 142         ret = LzmaDecode(&lzma_state, lzma_data, lzma_datasize, &ip, outStream,
 143                          lzma_outsize, &op);
 144
 145         if (ret != LZMA_RESULT_OK) {
 146                 int i;
 147
 148                 DBG("LzmaDecode error %d at %08x, osize:%d ip:%d op:%d\n",
 149                     ret, lzma_data + ip, lzma_outsize, ip, op);
 150
 151                 for (i = 0; i < 16; i++)
 152                         DBG("%02x ", lzma_data[ip + i]);
 153
 154                 DBG("\n");
 155         }
 156
 157         return ret;
 158 }
 159
 160 #if (LZMA_WRAPPER)
 161 static void lzma_init_data(void)
 162 {
 163         extern unsigned char _lzma_data_start[];
 164         extern unsigned char _lzma_data_end[];
 165
 166         kernel_la = LOADADDR;
 167         lzma_data = _lzma_data_start;
 168         lzma_datasize = _lzma_data_end - _lzma_data_start;
 169 }
 170 #else
 171 static void lzma_init_data(void)
 172 {
 173         struct image_header *hdr = NULL;
 174         unsigned char *flash_base;
 175         unsigned long flash_ofs;
 176         unsigned long kernel_ofs;
 177         unsigned long kernel_size;
 178
 179         flash_base = (unsigned char *) KSEG1ADDR(AR71XX_FLASH_START);
 180
 181         printf("Looking for OpenWrt image... ");
 182
 183         for (flash_ofs = CONFIG_FLASH_OFFS;
 184              flash_ofs <= (CONFIG_FLASH_OFFS + CONFIG_FLASH_MAX);
 185              flash_ofs += CONFIG_FLASH_STEP) {
 186                 unsigned long magic;
 187                 unsigned char *p;
 188
 189                 p = flash_base + flash_ofs;
 190                 magic = get_be32(p);
 191                 if (magic == IH_MAGIC_OKLI) {
 192                         hdr = (struct image_header *) p;
 193                         break;
 194                 }
 195         }
 196
 197         if (hdr == NULL) {
 198                 printf("not found!\n");
 199                 halt();
 200         }
 201
 202         printf("found at 0x%08x\n", flash_base + flash_ofs);
 203
 204         kernel_ofs = sizeof(struct image_header);
 205         kernel_size = get_be32(&hdr->ih_size);
 206         kernel_la = get_be32(&hdr->ih_load);
 207
 208         lzma_data = flash_base + flash_ofs + kernel_ofs;
 209         lzma_datasize = kernel_size;
 210 }
 211 #endif /* (LZMA_WRAPPER) */
 212
 213 void loader_main(unsigned long reg_a0, unsigned long reg_a1,
 214                  unsigned long reg_a2, unsigned long reg_a3)
 215 {
 216         void (*kernel_entry) (unsigned long, unsigned long, unsigned long,
 217                               unsigned long);
 218         int res;
 219
 220         board_init();
 221
 222         printf("\n\nOpenWrt kernel loader for MIPS based SoC\n");
 223         printf("Copyright (C) 2011 Gabor Juhos <juhosg@openwrt.org>\n");
 224
 225         lzma_init_data();
 226
 227         res = lzma_init_props();
 228         if (res != LZMA_RESULT_OK) {
 229                 printf("Incorrect LZMA stream properties!\n");
 230                 halt();
 231         }
 232
 233         printf("Decompressing kernel... ");
 234
 235         res = lzma_decompress((unsigned char *) kernel_la);
 236         if (res != LZMA_RESULT_OK) {
 237                 printf("failed, ");
 238                 switch (res) {
 239                 case LZMA_RESULT_DATA_ERROR:
 240                         printf("data error!\n");
 241                         break;
 242                 default:
 243                         printf("unknown error %d!\n", res);
 244                 }
 245                 halt();
 246         } else {
 247                 printf("done!\n");
 248         }
 249
 250         flush_cache(kernel_la, lzma_outsize);
 251
 252         printf("Starting kernel at %08x...\n\n", kernel_la);
 253
 254 #ifdef CONFIG_KERNEL_CMDLINE
 255         reg_a0 = kernel_argc;
 256         reg_a1 = (unsigned long) kernel_argv;
 257         reg_a2 = 0;
 258         reg_a3 = 0;
 259 #endif
 260
 261         kernel_entry = (void *) kernel_la;
 262         kernel_entry(reg_a0, reg_a1, reg_a2, reg_a3);
 263 }