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