arch/alpha/boot/misc.c

   1 /*
   2  * misc.c
   3  *
   4  * This is a collection of several routines from gzip-1.0.3
   5  * adapted for Linux.
   6  *
   7  * malloc by Hannu Savolainen 1993 and Matthias Urlichs 1994
   8  *
   9  * Modified for ARM Linux by Russell King
  10  *
  11  * Nicolas Pitre <nico@visuaide.com>  1999/04/14 :
  12  *  For this code to run directly from Flash, all constant variables must
  13  *  be marked with 'const' and all other variables initialized at run-time
  14  *  only.  This way all non constant variables will end up in the bss segment,
  15  *  which should point to addresses in RAM and cleared to 0 on start.
  16  *  This allows for a much quicker boot time.
  17  *
  18  * Modified for Alpha, from the ARM version, by Jay Estabrook 2003.
  19  */
  20
  21 #include <linux/kernel.h>
  22 #include <linux/slab.h>
  23
  24 #include <asm/uaccess.h>
  25
  26 #define memzero(s,n)    memset ((s),0,(n))
  27 #define puts            srm_printk
  28 extern long srm_printk(const char *, ...)
  29      __attribute__ ((format (printf, 1, 2)));
  30
  31 /*
  32  * gzip delarations
  33  */
  34 #define OF(args)  args
  35 #define STATIC static
  36
  37 typedef unsigned char  uch;
  38 typedef unsigned short ush;
  39 typedef unsigned long  ulg;
  40
  41 #define WSIZE 0x8000            /* Window size must be at least 32k, */
  42                                 /* and a power of two */
  43
  44 static uch *inbuf;              /* input buffer */
  45 static uch *window;             /* Sliding window buffer */
  46
  47 static unsigned insize;         /* valid bytes in inbuf */
  48 static unsigned inptr;          /* index of next byte to be processed in inbuf */
  49 static unsigned outcnt;         /* bytes in output buffer */
  50
  51 /* gzip flag byte */
  52 #define ASCII_FLAG   0x01 /* bit 0 set: file probably ascii text */
  53 #define CONTINUATION 0x02 /* bit 1 set: continuation of multi-part gzip file */
  54 #define EXTRA_FIELD  0x04 /* bit 2 set: extra field present */
  55 #define ORIG_NAME    0x08 /* bit 3 set: original file name present */
  56 #define COMMENT      0x10 /* bit 4 set: file comment present */
  57 #define ENCRYPTED    0x20 /* bit 5 set: file is encrypted */
  58 #define RESERVED     0xC0 /* bit 6,7:   reserved */
  59
  60 #define get_byte()  (inptr < insize ? inbuf[inptr++] : fill_inbuf())
  61
  62 /* Diagnostic functions */
  63 #ifdef DEBUG
  64 #  define Assert(cond,msg) {if(!(cond)) error(msg);}
  65 #  define Trace(x) fprintf x
  66 #  define Tracev(x) {if (verbose) fprintf x ;}
  67 #  define Tracevv(x) {if (verbose>1) fprintf x ;}
  68 #  define Tracec(c,x) {if (verbose && (c)) fprintf x ;}
  69 #  define Tracecv(c,x) {if (verbose>1 && (c)) fprintf x ;}
  70 #else
  71 #  define Assert(cond,msg)
  72 #  define Trace(x)
  73 #  define Tracev(x)
  74 #  define Tracevv(x)
  75 #  define Tracec(c,x)
  76 #  define Tracecv(c,x)
  77 #endif
  78
  79 static int  fill_inbuf(void);
  80 static void flush_window(void);
  81 static void error(char *m);
  82
  83 static char *input_data;
  84 static int  input_data_size;
  85
  86 static uch *output_data;
  87 static ulg output_ptr;
  88 static ulg bytes_out;
  89
  90 static void error(char *m);
  91 static void gzip_mark(void **);
  92 static void gzip_release(void **);
  93
  94 extern int end;
  95 static ulg free_mem_ptr;
  96 static ulg free_mem_end_ptr;
  97
  98 #define HEAP_SIZE 0x3000
  99
 100 #include "../../../lib/inflate.c"
 101
 102 /* ===========================================================================
 103  * Fill the input buffer. This is called only when the buffer is empty
 104  * and at least one byte is really needed.
 105  */
 106 int fill_inbuf(void)
 107 {
 108         if (insize != 0)
 109                 error("ran out of input data");
 110
 111         inbuf = input_data;
 112         insize = input_data_size;
 113
 114         inptr = 1;
 115         return inbuf[0];
 116 }
 117
 118 /* ===========================================================================
 119  * Write the output window window[0..outcnt-1] and update crc and bytes_out.
 120  * (Used for the decompressed data only.)
 121  */
 122 void flush_window(void)
 123 {
 124         ulg c = crc;
 125         unsigned n;
 126         uch *in, *out, ch;
 127
 128         in = window;
 129         out = &output_data[output_ptr];
 130         for (n = 0; n < outcnt; n++) {
 131                 ch = *out++ = *in++;
 132                 c = crc_32_tab[((int)c ^ ch) & 0xff] ^ (c >> 8);
 133         }
 134         crc = c;
 135         bytes_out += (ulg)outcnt;
 136         output_ptr += (ulg)outcnt;
 137         outcnt = 0;
 138 /*      puts("."); */
 139 }
 140
 141 static void error(char *x)
 142 {
 143         puts("\n\n");
 144         puts(x);
 145         puts("\n\n -- System halted");
 146
 147         while(1);       /* Halt */
 148 }
 149
 150 unsigned int
 151 decompress_kernel(void *output_start,
 152                   void *input_start,
 153                   size_t ksize,
 154                   size_t kzsize)
 155 {
 156         output_data             = (uch *)output_start;
 157         input_data              = (uch *)input_start;
 158         input_data_size         = kzsize; /* use compressed size */
 159
 160         /* FIXME FIXME FIXME */
 161         free_mem_ptr            = (ulg)output_start + ksize;
 162         free_mem_end_ptr        = (ulg)output_start + ksize + 0x200000;
 163         /* FIXME FIXME FIXME */
 164
 165         /* put in temp area to reduce initial footprint */
 166         window = malloc(WSIZE);
 167
 168         makecrc();
 169 /*      puts("Uncompressing Linux..."); */
 170         gunzip();
 171 /*      puts(" done, booting the kernel.\n"); */
 172         return output_ptr;
 173 }