target/linux/bcm63xx/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 KSEG0                   0x80000000
  31 #define KSEG1                   0xa0000000
  32
  33 #define KSEG1ADDR(a)            ((((unsigned)(a)) & 0x1fffffffU) | KSEG1)
  34
  35 #undef LZMA_DEBUG
  36
  37 #ifdef LZMA_DEBUG
  38 #  define DBG(f, a...)  printf(f, ## a)
  39 #else
  40 #  define DBG(f, a...)  do {} while (0)
  41 #endif
  42
  43 /* beyond the image end, size not known in advance */
  44 extern unsigned char workspace[];
  45
  46
  47 extern void board_init(void);
  48
  49 static CLzmaDecoderState lzma_state;
  50 static unsigned char *lzma_data;
  51 static unsigned long lzma_datasize;
  52 static unsigned long lzma_outsize;
  53 static unsigned long kernel_la;
  54
  55 static void halt(void)
  56 {
  57         printf("\nSystem halted!\n");
  58         for(;;);
  59 }
  60
  61 static __inline__ unsigned char lzma_get_byte(void)
  62 {
  63         unsigned char c;
  64
  65         lzma_datasize--;
  66         c = *lzma_data++;
  67
  68         return c;
  69 }
  70
  71 static int lzma_init_props(void)
  72 {
  73         unsigned char props[LZMA_PROPERTIES_SIZE];
  74         int res;
  75         int i;
  76
  77         /* read lzma properties */
  78         for (i = 0; i < LZMA_PROPERTIES_SIZE; i++)
  79                 props[i] = lzma_get_byte();
  80
  81         /* read the lower half of uncompressed size in the header */
  82         lzma_outsize = ((SizeT) lzma_get_byte()) +
  83                        ((SizeT) lzma_get_byte() << 8) +
  84                        ((SizeT) lzma_get_byte() << 16) +
  85                        ((SizeT) lzma_get_byte() << 24);
  86
  87         /* skip rest of the header (upper half of uncompressed size) */
  88         for (i = 0; i < 4; i++)
  89                 lzma_get_byte();
  90
  91         res = LzmaDecodeProperties(&lzma_state.Properties, props,
  92                                         LZMA_PROPERTIES_SIZE);
  93         return res;
  94 }
  95
  96 static int lzma_decompress(unsigned char *outStream)
  97 {
  98         SizeT ip, op;
  99         int ret;
 100
 101         lzma_state.Probs = (CProb *) workspace;
 102
 103         ret = LzmaDecode(&lzma_state, lzma_data, lzma_datasize, &ip, outStream,
 104                          lzma_outsize, &op);
 105
 106         if (ret != LZMA_RESULT_OK) {
 107                 int i;
 108
 109                 DBG("LzmaDecode error %d at %08x, osize:%d ip:%d op:%d\n",
 110                     ret, lzma_data + ip, lzma_outsize, ip, op);
 111
 112                 for (i = 0; i < 16; i++)
 113                         DBG("%02x ", lzma_data[ip + i]);
 114
 115                 DBG("\n");
 116         }
 117
 118         return ret;
 119 }
 120
 121 static void lzma_init_data(void)
 122 {
 123         extern unsigned char _lzma_data_start[];
 124         extern unsigned char _lzma_data_end[];
 125
 126         kernel_la = LOADADDR;
 127         lzma_data = _lzma_data_start;
 128         lzma_datasize = _lzma_data_end - _lzma_data_start;
 129 }
 130
 131 void loader_main(unsigned long reg_a0, unsigned long reg_a1,
 132                  unsigned long reg_a2, unsigned long reg_a3)
 133 {
 134         void (*kernel_entry) (unsigned long, unsigned long, unsigned long,
 135                               unsigned long);
 136         int res;
 137
 138         board_init();
 139
 140         printf("\n\nOpenWrt kernel loader for BCM63XX\n");
 141         printf("Copyright (C) 2011 Gabor Juhos <juhosg@openwrt.org>\n");
 142         printf("Copyright (C) 2014 Jonas Gorski <jogo@openwrt.org>\n");
 143
 144         lzma_init_data();
 145
 146         res = lzma_init_props();
 147         if (res != LZMA_RESULT_OK) {
 148                 printf("Incorrect LZMA stream properties!\n");
 149                 halt();
 150         }
 151
 152         printf("Decompressing kernel... ");
 153
 154         res = lzma_decompress((unsigned char *) kernel_la);
 155         if (res != LZMA_RESULT_OK) {
 156                 printf("failed, ");
 157                 switch (res) {
 158                 case LZMA_RESULT_DATA_ERROR:
 159                         printf("data error!\n");
 160                         break;
 161                 default:
 162                         printf("unknown error %d!\n", res);
 163                 }
 164                 halt();
 165         } else {
 166                 printf("done!\n");
 167         }
 168
 169         flush_cache(kernel_la, lzma_outsize);
 170
 171         printf("Starting kernel at %08x...\n\n", kernel_la);
 172
 173         kernel_entry = (void *) kernel_la;
 174         kernel_entry(reg_a0, reg_a1, reg_a2, reg_a3);
 175 }