LXR linux/arch/m32r/boot/compressed/misc.c

   1/*
   2 * arch/m32r/boot/compressed/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 * Adapted for SH by Stuart Menefy, Aug 1999
  10 *
  11 * 2003-02-12:  Support M32R by Takeo Takahashi
  12 *              This is based on arch/sh/boot/compressed/misc.c.
  13 */
  14
  15#include <linux/string.h>
  16
  17/*
  18 * gzip declarations
  19 */
  20
  21#define OF(args)  args
  22#define STATIC static
  23
  24#undef memset
  25#undef memcpy
  26#define memzero(s, n)     memset ((s), 0, (n))
  27
  28typedef unsigned char  uch;
  29typedef unsigned short ush;
  30typedef unsigned long  ulg;
  31
  32#define WSIZE 0x8000            /* Window size must be at least 32k, */
  33                                /* and a power of two */
  34
  35static uch *inbuf;           /* input buffer */
  36static uch window[WSIZE];    /* Sliding window buffer */
  37
  38static unsigned insize = 0;  /* valid bytes in inbuf */
  39static unsigned inptr = 0;   /* index of next byte to be processed in inbuf */
  40static unsigned outcnt = 0;  /* bytes in output buffer */
  41
  42/* gzip flag byte */
  43#define ASCII_FLAG   0x01 /* bit 0 set: file probably ASCII text */
  44#define CONTINUATION 0x02 /* bit 1 set: continuation of multi-part gzip file */
  45#define EXTRA_FIELD  0x04 /* bit 2 set: extra field present */
  46#define ORIG_NAME    0x08 /* bit 3 set: original file name present */
  47#define COMMENT      0x10 /* bit 4 set: file comment present */
  48#define ENCRYPTED    0x20 /* bit 5 set: file is encrypted */
  49#define RESERVED     0xC0 /* bit 6,7:   reserved */
  50
  51#define get_byte()  (inptr < insize ? inbuf[inptr++] : fill_inbuf())
  52
  53/* Diagnostic functions */
  54#ifdef DEBUG
  55#  define Assert(cond,msg) {if(!(cond)) error(msg);}
  56#  define Trace(x) fprintf x
  57#  define Tracev(x) {if (verbose) fprintf x ;}
  58#  define Tracevv(x) {if (verbose>1) fprintf x ;}
  59#  define Tracec(c,x) {if (verbose && (c)) fprintf x ;}
  60#  define Tracecv(c,x) {if (verbose>1 && (c)) fprintf x ;}
  61#else
  62#  define Assert(cond,msg)
  63#  define Trace(x)
  64#  define Tracev(x)
  65#  define Tracevv(x)
  66#  define Tracec(c,x)
  67#  define Tracecv(c,x)
  68#endif
  69
  70static int  fill_inbuf(void);
  71static void flush_window(void);
  72static void error(char *m);
  73
  74static unsigned char *input_data;
  75static int input_len;
  76
  77static long bytes_out = 0;
  78static uch *output_data;
  79static unsigned long output_ptr = 0;
  80
  81#include "m32r_sio.c"
  82
  83static unsigned long free_mem_ptr;
  84static unsigned long free_mem_end_ptr;
  85
  86#define HEAP_SIZE             0x10000
  87
  88#include "../../../../lib/inflate.c"
  89
  90void* memset(void* s, int c, size_t n)
  91{
  92        int i;
  93        char *ss = (char*)s;
  94
  95        for (i=0;i<n;i++) ss[i] = c;
  96        return s;
  97}
  98
  99void* memcpy(void* __dest, __const void* __src,
 100                            size_t __n)
 101{
 102        int i;
 103        char *d = (char *)__dest, *s = (char *)__src;
 104
 105        for (i=0;i<__n;i++) d[i] = s[i];
 106        return __dest;
 107}
 108
 109/* ===========================================================================
 110 * Fill the input buffer. This is called only when the buffer is empty
 111 * and at least one byte is really needed.
 112 */
 113static int fill_inbuf(void)
 114{
 115        if (insize != 0) {
 116                error("ran out of input data");
 117        }
 118
 119        inbuf = input_data;
 120        insize = input_len;
 121        inptr = 1;
 122        return inbuf[0];
 123}
 124
 125/* ===========================================================================
 126 * Write the output window window[0..outcnt-1] and update crc and bytes_out.
 127 * (Used for the decompressed data only.)
 128 */
 129static void flush_window(void)
 130{
 131    ulg c = crc;         /* temporary variable */
 132    unsigned n;
 133    uch *in, *out, ch;
 134
 135    in = window;
 136    out = &output_data[output_ptr];
 137    for (n = 0; n < outcnt; n++) {
 138            ch = *out++ = *in++;
 139            c = crc_32_tab[((int)c ^ ch) & 0xff] ^ (c >> 8);
 140    }
 141    crc = c;
 142    bytes_out += (ulg)outcnt;
 143    output_ptr += (ulg)outcnt;
 144    outcnt = 0;
 145}
 146
 147static void error(char *x)
 148{
 149        puts("\n\n");
 150        puts(x);
 151        puts("\n\n -- System halted");
 152
 153        while(1);       /* Halt */
 154}
 155
 156/* return decompressed size */
 157void
 158decompress_kernel(int mmu_on, unsigned char *zimage_data,
 159                  unsigned int zimage_len, unsigned long heap)
 160{
 161        output_data = (unsigned char *)CONFIG_MEMORY_START + 0x2000
 162                + (mmu_on ? 0x80000000 : 0);
 163        free_mem_ptr = heap;
 164        free_mem_end_ptr = free_mem_ptr + HEAP_SIZE;
 165        input_data = zimage_data;
 166        input_len = zimage_len;
 167
 168        makecrc();
 169        puts("Uncompressing Linux... ");
 170        gunzip();
 171        puts("Ok, booting the kernel.\n");
 172}
 173