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
  27 extern 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
  36 typedef unsigned char  uch;
  37 typedef unsigned short ush;
  38 typedef unsigned long  ulg;
  39
  40 #define WSIZE 0x8000            /* Window size must be at least 32k, */
  41                                 /* and a power of two */
  42
  43 static uch *inbuf;              /* input buffer */
  44 static uch *window;             /* Sliding window buffer */
  45
  46 static unsigned insize;         /* valid bytes in inbuf */
  47 static unsigned inptr;          /* index of next byte to be processed in inbuf */
  48 static 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
  78 static int  fill_inbuf(void);
  79 static void flush_window(void);
  80 static void error(char *m);
  81 static void gzip_mark(void **);
  82 static void gzip_release(void **);
  83
  84 static char *input_data;
  85 static int  input_data_size;
  86
  87 static uch *output_data;
  88 static ulg output_ptr;
  89 static ulg bytes_out;
  90
  91 static void *malloc(int size);
  92 static void free(void *where);
  93 static void error(char *m);
  94 static void gzip_mark(void **);
  95 static void gzip_release(void **);
  96
  97 extern int end;
  98 static ulg free_mem_ptr;
  99 static ulg free_mem_ptr_end;
 100
 101 #define HEAP_SIZE 0x3000
 102
 103 #include "../../../lib/inflate.c"
 104
 105 static void *malloc(int size)
 106 {
 107         void *p;
 108
 109         if (size <0) error("Malloc error");
 110         if (free_mem_ptr <= 0) error("Memory error");
 111
 112         free_mem_ptr = (free_mem_ptr + 3) & ~3; /* Align */
 113
 114         p = (void *)free_mem_ptr;
 115         free_mem_ptr += size;
 116
 117         if (free_mem_ptr >= free_mem_ptr_end)
 118                 error("Out of memory");
 119         return p;
 120 }
 121
 122 static void free(void *where)
 123 { /* gzip_mark & gzip_release do the free */
 124 }
 125
 126 static void gzip_mark(void **ptr)
 127 {
 128         *ptr = (void *) free_mem_ptr;
 129 }
 130
 131 static void gzip_release(void **ptr)
 132 {
 133         free_mem_ptr = (long) *ptr;
 134 }
 135
 136 /* ===========================================================================
 137  * Fill the input buffer. This is called only when the buffer is empty
 138  * and at least one byte is really needed.
 139  */
 140 int fill_inbuf(void)
 141 {
 142         if (insize != 0)
 143                 error("ran out of input data");
 144
 145         inbuf = input_data;
 146         insize = input_data_size;
 147
 148         inptr = 1;
 149         return inbuf[0];
 150 }
 151
 152 /* ===========================================================================
 153  * Write the output window window[0..outcnt-1] and update crc and bytes_out.
 154  * (Used for the decompressed data only.)
 155  */
 156 void flush_window(void)
 157 {
 158         ulg c = crc;
 159         unsigned n;
 160         uch *in, *out, ch;
 161
 162         in = window;
 163         out = &output_data[output_ptr];
 164         for (n = 0; n < outcnt; n++) {
 165                 ch = *out++ = *in++;
 166                 c = crc_32_tab[((int)c ^ ch) & 0xff] ^ (c >> 8);
 167         }
 168         crc = c;
 169         bytes_out += (ulg)outcnt;
 170         output_ptr += (ulg)outcnt;
 171         outcnt = 0;
 172 /*      puts("."); */
 173 }
 174
 175 static void error(char *x)
 176 {
 177         puts("\n\n");
 178         puts(x);
 179         puts("\n\n -- System halted");
 180
 181         while(1);       /* Halt */
 182 }
 183
 184 unsigned int
 185 decompress_kernel(void *output_start,
 186                   void *input_start,
 187                   size_t ksize,
 188                   size_t kzsize)
 189 {
 190         output_data             = (uch *)output_start;
 191         input_data              = (uch *)input_start;
 192         input_data_size         = kzsize; /* use compressed size */
 193
 194         /* FIXME FIXME FIXME */
 195         free_mem_ptr            = (ulg)output_start + ksize;
 196         free_mem_ptr_end        = (ulg)output_start + ksize + 0x200000;
 197         /* FIXME FIXME FIXME */
 198
 199         /* put in temp area to reduce initial footprint */
 200         window = malloc(WSIZE);
 201
 202         makecrc();
 203 /*      puts("Uncompressing Linux..."); */
 204         gunzip();
 205 /*      puts(" done, booting the kernel.\n"); */
 206         return output_ptr;
 207 }