openwrt/target/linux/image/ar7/src/loader.c

   1 /* inflate.c -- Not copyrighted 1992 by Mark Adler
   2    version c10p1, 10 January 1993 */
   3
   4 /*
   5  * Adapted for booting Linux by Hannu Savolainen 1993
   6  * based on gzip-1.0.3
   7  *
   8  * Nicolas Pitre <nico@visuaide.com>, 1999/04/14 :
   9  *   Little mods for all variable to reside either into rodata or bss segments
  10  *   by marking constant variables with 'const' and initializing all the others
  11  *   at run-time only.  This allows for the kernel uncompressor to run
  12  *   directly from Flash or ROM memory on embeded systems.
  13  */
  14
  15 #include <linux/config.h>
  16 #include "gzip.h"
  17 #include "LzmaDecode.h"
  18
  19 /* Function prototypes */
  20 unsigned char get_byte(void);
  21 int tikernelunzip(int,char *[], char *[]);
  22 static int tidecompress(uch *, uch *);
  23
  24 void kernel_entry(int, char *[], char *[]);
  25 void (*ke)(int, char *[], char *[]); /* Gen reference to kernel function */
  26 void (*prnt)(unsigned int, char *);             /* Gen reference to Yamon print function */
  27 void printf(char *ptr);                 /* Generate our own printf */
  28
  29 int tikernelunzip(int argc, char *argv[], char *arge[])
  30 {
  31         extern unsigned int _ftext;
  32         extern uch kernelimage[];
  33         uch *in, *out;
  34         int status;
  35
  36         printf("Launching kernel decompressor.\n");
  37
  38         out = (unsigned char *) LOADADDR;
  39         in = &(kernelimage[0]);
  40
  41         status = tidecompress(in, out);
  42
  43         if (status == 0) {
  44                 printf("Kernel decompressor was successful ... launching kernel.\n");
  45
  46                 ke = ( void(*)(int, char *[],char*[]))kernel_entry;
  47                 (*ke)(argc,argv,arge);
  48
  49                 return (0);
  50         } else {
  51                 printf("Error in decompression.\n");
  52                 return(1);
  53         }
  54 }
  55
  56 #if 0
  57 char hex[] = {'0', '1', '2', '3', '4', '5', '6', '7', '8', '9', 'A', 'B', 'C', 'D', 'E', 'F'};
  58 void print_i(int i)
  59 {
  60         int j;
  61         char buf[11];
  62
  63         buf[0] = '0';
  64         buf[1] = 'x';
  65         buf[10] = 0;
  66
  67         for (j = 0; j < 8; j++)
  68         {
  69                 buf[2 + 7 - j] = hex[i & 0xf];
  70                 i = i >> 4;
  71         }
  72
  73         printf(buf);
  74 }
  75 #endif
  76
  77 int tidecompress(uch *indata, uch *outdata)
  78 {
  79         extern unsigned int workspace;
  80         extern unsigned char kernelimage[], kernelimage_end[];
  81         unsigned int i;  /* temp value */
  82         unsigned int lc; /* literal context bits */
  83         unsigned int lp; /* literal pos state bits */
  84         unsigned int pb; /* pos state bits */
  85         unsigned int osize; /* uncompressed size */
  86         unsigned int wsize; /* window size */
  87         unsigned int insize = kernelimage_end - kernelimage;
  88         int status;
  89
  90         output_ptr = 0;
  91         output_data = outdata;
  92         input_data = indata;
  93
  94         /* lzma args */
  95         i = get_byte();
  96         lc = i % 9, i = i / 9;
  97         lp = i % 5, pb = i / 5;
  98
  99         /* skip rest of the LZMA coder property */
 100         for (i = 0; i < 4; i++)
 101                 get_byte();
 102
 103         /* read the lower half of uncompressed size in the header */
 104         osize = ((unsigned int)get_byte()) +
 105                 ((unsigned int)get_byte() << 8) +
 106                 ((unsigned int)get_byte() << 16) +
 107                 ((unsigned int)get_byte() << 24);
 108
 109         /* skip rest of the header (upper half of uncompressed size) */
 110         for (i = 0; i < 4; i++)
 111                 get_byte();
 112
 113         i = 0;
 114         wsize = (LZMA_BASE_SIZE + (LZMA_LIT_SIZE << (lc + lp))) * sizeof(CProb);
 115
 116         if ((status = LzmaDecode((unsigned char *) &workspace, wsize, lc, lp, pb,
 117                 indata + 13, insize - 13, (unsigned char *) output_data, osize, &i)) == LZMA_RESULT_OK)
 118                         return 0;
 119
 120         return status;
 121 }
 122
 123
 124 void printf(char *ptr)
 125 {
 126         unsigned int *tempptr = (unsigned int  *)0x90000534;
 127         prnt = ( void (*)(unsigned int, char *)) *tempptr;
 128         (*prnt)(0,ptr);
 129 }
 130
 131 unsigned char get_byte()
 132 {
 133         unsigned char c;
 134
 135         c = *input_data;
 136         input_data++;
 137
 138         return c;
 139 }
 140