target/linux/ar71xx/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     2
  77 static const char kernel_cmdline[] = CONFIG_KERNEL_CMDLINE;
  78 static const char *const kernel_argv[] = {
  79         NULL,
  80         kernel_cmdline,
  81         NULL,
  82 };
  83 #endif /* CONFIG_KERNEL_CMDLINE */
  84
  85 static void halt(void)
  86 {
  87         printf("\nSystem halted!\n");
  88         for(;;);
  89 }
  90
  91 static __inline__ unsigned long get_be32(void *buf)
  92 {
  93         unsigned char *p = buf;
  94
  95         return (((unsigned long) p[0] << 24) +
  96                 ((unsigned long) p[1] << 16) +
  97                 ((unsigned long) p[2] << 8) +
  98                 (unsigned long) p[3]);
  99 }
 100
 101 static __inline__ unsigned char lzma_get_byte(void)
 102 {
 103         unsigned char c;
 104
 105         lzma_datasize--;
 106         c = *lzma_data++;
 107
 108         return c;
 109 }
 110
 111 static int lzma_init_props(void)
 112 {
 113         unsigned char props[LZMA_PROPERTIES_SIZE];
 114         int res;
 115         int i;
 116
 117         /* read lzma properties */
 118         for (i = 0; i < LZMA_PROPERTIES_SIZE; i++)
 119                 props[i] = lzma_get_byte();
 120
 121         /* read the lower half of uncompressed size in the header */
 122         lzma_outsize = ((SizeT) lzma_get_byte()) +
 123                        ((SizeT) lzma_get_byte() << 8) +
 124                        ((SizeT) lzma_get_byte() << 16) +
 125                        ((SizeT) lzma_get_byte() << 24);
 126
 127         /* skip rest of the header (upper half of uncompressed size) */
 128         for (i = 0; i < 4; i++)
 129                 lzma_get_byte();
 130
 131         res = LzmaDecodeProperties(&lzma_state.Properties, props,
 132                                         LZMA_PROPERTIES_SIZE);
 133         return res;
 134 }
 135
 136 static int lzma_decompress(unsigned char *outStream)
 137 {
 138         SizeT ip, op;
 139         int ret;
 140
 141         lzma_state.Probs = (CProb *) workspace;
 142
 143         ret = LzmaDecode(&lzma_state, lzma_data, lzma_datasize, &ip, outStream,
 144                          lzma_outsize, &op);
 145
 146         if (ret != LZMA_RESULT_OK) {
 147                 int i;
 148
 149                 DBG("LzmaDecode error %d at %08x, osize:%d ip:%d op:%d\n",
 150                     ret, lzma_data + ip, lzma_outsize, ip, op);
 151
 152                 for (i = 0; i < 16; i++)
 153                         DBG("%02x ", lzma_data[ip + i]);
 154
 155                 DBG("\n");
 156         }
 157
 158         return ret;
 159 }
 160
 161 #if (LZMA_WRAPPER)
 162 static void lzma_init_data(void)
 163 {
 164         extern unsigned char _lzma_data_start[];
 165         extern unsigned char _lzma_data_end[];
 166
 167         kernel_la = LOADADDR;
 168         lzma_data = _lzma_data_start;
 169         lzma_datasize = _lzma_data_end - _lzma_data_start;
 170 }
 171 #else
 172 static void lzma_init_data(void)
 173 {
 174         struct image_header *hdr = NULL;
 175         unsigned char *flash_base;
 176         unsigned long flash_ofs;
 177         unsigned long kernel_ofs;
 178         unsigned long kernel_size;
 179
 180         flash_base = (unsigned char *) KSEG1ADDR(AR71XX_FLASH_START);
 181
 182         printf("Looking for libreCMC image... ");
 183
 184         for (flash_ofs = CONFIG_FLASH_OFFS;
 185              flash_ofs <= (CONFIG_FLASH_OFFS + CONFIG_FLASH_MAX);
 186              flash_ofs += CONFIG_FLASH_STEP) {
 187                 unsigned long magic;
 188                 unsigned char *p;
 189
 190                 p = flash_base + flash_ofs;
 191                 magic = get_be32(p);
 192                 if (magic == IH_MAGIC_OKLI) {
 193                         hdr = (struct image_header *) p;
 194                         break;
 195                 }
 196         }
 197
 198         if (hdr == NULL) {
 199                 printf("not found!\n");
 200                 halt();
 201         }
 202
 203         printf("found at 0x%08x\n", flash_base + flash_ofs);
 204
 205         kernel_ofs = sizeof(struct image_header);
 206         kernel_size = get_be32(&hdr->ih_size);
 207         kernel_la = get_be32(&hdr->ih_load);
 208
 209         lzma_data = flash_base + flash_ofs + kernel_ofs;
 210         lzma_datasize = kernel_size;
 211 }
 212 #endif /* (LZMA_WRAPPER) */
 213
 214 void loader_main(unsigned long reg_a0, unsigned long reg_a1,
 215                  unsigned long reg_a2, unsigned long reg_a3)
 216 {
 217         void (*kernel_entry) (unsigned long, unsigned long, unsigned long,
 218                               unsigned long);
 219         int res;
 220
 221         board_init();
 222
 223         printf("\n\nOpenWrt kernel loader for AR7XXX/AR9XXX\n");
 224         printf("Copyright (C) 2011 Gabor Juhos <juhosg@openwrt.org>\n");
 225
 226         lzma_init_data();
 227
 228         res = lzma_init_props();
 229         if (res != LZMA_RESULT_OK) {
 230                 printf("Incorrect LZMA stream properties!\n");
 231                 halt();
 232         }
 233
 234         printf("Decompressing kernel... ");
 235
 236         res = lzma_decompress((unsigned char *) kernel_la);
 237         if (res != LZMA_RESULT_OK) {
 238                 printf("failed, ");
 239                 switch (res) {
 240                 case LZMA_RESULT_DATA_ERROR:
 241                         printf("data error!\n");
 242                         break;
 243                 default:
 244                         printf("unknown error %d!\n", res);
 245                 }
 246                 halt();
 247         } else {
 248                 printf("done!\n");
 249         }
 250
 251         flush_cache(kernel_la, lzma_outsize);
 252
 253         printf("Starting kernel at %08x...\n\n", kernel_la);
 254
 255 #ifdef CONFIG_KERNEL_CMDLINE
 256         reg_a0 = kernel_argc;
 257         reg_a1 = (unsigned long) kernel_argv;
 258         reg_a2 = 0;
 259         reg_a3 = 0;
 260 #endif
 261
 262         kernel_entry = (void *) kernel_la;
 263         kernel_entry(reg_a0, reg_a1, reg_a2, reg_a3);
 264 }