arch/i386/boot/compressed/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  * puts by Nick Holloway 1993, better puts by Martin Mares 1995
   9  * High loaded stuff by Hans Lermen & Werner Almesberger, Feb. 1996
  10  */
  11
  12 #include <linux/linkage.h>
  13 #include <linux/vmalloc.h>
  14 #include <linux/tty.h>
  15 #include <video/edid.h>
  16 #include <asm/io.h>
  17
  18 /*
  19  * gzip declarations
  20  */
  21
  22 #define OF(args)  args
  23 #define STATIC static
  24
  25 #undef memset
  26 #undef memcpy
  27
  28 /*
  29  * Why do we do this? Don't ask me..
  30  *
  31  * Incomprehensible are the ways of bootloaders.
  32  */
  33 static void* memset(void *, int, size_t);
  34 static void* memcpy(void *, __const void *, size_t);
  35 #define memzero(s, n)     memset ((s), 0, (n))
  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[WSIZE];    /* Sliding window buffer */
  46
  47 static unsigned insize = 0;  /* valid bytes in inbuf */
  48 static unsigned inptr = 0;   /* index of next byte to be processed in inbuf */
  49 static unsigned outcnt = 0;  /* 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 static void gzip_mark(void **);
  83 static void gzip_release(void **);
  84
  85 /*
  86  * This is set up by the setup-routine at boot-time
  87  */
  88 static unsigned char *real_mode; /* Pointer to real-mode data */
  89
  90 #define RM_EXT_MEM_K   (*(unsigned short *)(real_mode + 0x2))
  91 #ifndef STANDARD_MEMORY_BIOS_CALL
  92 #define RM_ALT_MEM_K   (*(unsigned long *)(real_mode + 0x1e0))
  93 #endif
  94 #define RM_SCREEN_INFO (*(struct screen_info *)(real_mode+0))
  95
  96 extern char input_data[];
  97 extern int input_len;
  98
  99 static long bytes_out = 0;
 100 static uch *output_data;
 101 static unsigned long output_ptr = 0;
 102
 103 static void *malloc(int size);
 104 static void free(void *where);
 105
 106 static void putstr(const char *);
 107
 108 extern int end;
 109 static long free_mem_ptr = (long)&end;
 110 static long free_mem_end_ptr;
 111
 112 #define INPLACE_MOVE_ROUTINE  0x1000
 113 #define LOW_BUFFER_START      0x2000
 114 #define LOW_BUFFER_MAX       0x90000
 115 #define HEAP_SIZE             0x3000
 116 static unsigned int low_buffer_end, low_buffer_size;
 117 static int high_loaded =0;
 118 static uch *high_buffer_start /* = (uch *)(((ulg)&end) + HEAP_SIZE)*/;
 119
 120 static char *vidmem = (char *)0xb8000;
 121 static int vidport;
 122 static int lines, cols;
 123
 124 #ifdef CONFIG_X86_NUMAQ
 125 static void * xquad_portio = NULL;
 126 #endif
 127
 128 #include "../../../../lib/inflate.c"
 129
 130 static void *malloc(int size)
 131 {
 132         void *p;
 133
 134         if (size <0) error("Malloc error");
 135         if (free_mem_ptr <= 0) error("Memory error");
 136
 137         free_mem_ptr = (free_mem_ptr + 3) & ~3; /* Align */
 138
 139         p = (void *)free_mem_ptr;
 140         free_mem_ptr += size;
 141
 142         if (free_mem_ptr >= free_mem_end_ptr)
 143                 error("Out of memory");
 144
 145         return p;
 146 }
 147
 148 static void free(void *where)
 149 {       /* Don't care */
 150 }
 151
 152 static void gzip_mark(void **ptr)
 153 {
 154         *ptr = (void *) free_mem_ptr;
 155 }
 156
 157 static void gzip_release(void **ptr)
 158 {
 159         free_mem_ptr = (long) *ptr;
 160 }
 161
 162 static void scroll(void)
 163 {
 164         int i;
 165
 166         memcpy ( vidmem, vidmem + cols * 2, ( lines - 1 ) * cols * 2 );
 167         for ( i = ( lines - 1 ) * cols * 2; i < lines * cols * 2; i += 2 )
 168                 vidmem[i] = ' ';
 169 }
 170
 171 static void putstr(const char *s)
 172 {
 173         int x,y,pos;
 174         char c;
 175
 176         x = RM_SCREEN_INFO.orig_x;
 177         y = RM_SCREEN_INFO.orig_y;
 178
 179         while ( ( c = *s++ ) != '\0' ) {
 180                 if ( c == '\n' ) {
 181                         x = 0;
 182                         if ( ++y >= lines ) {
 183                                 scroll();
 184                                 y--;
 185                         }
 186                 } else {
 187                         vidmem [ ( x + cols * y ) * 2 ] = c;
 188                         if ( ++x >= cols ) {
 189                                 x = 0;
 190                                 if ( ++y >= lines ) {
 191                                         scroll();
 192                                         y--;
 193                                 }
 194                         }
 195                 }
 196         }
 197
 198         RM_SCREEN_INFO.orig_x = x;
 199         RM_SCREEN_INFO.orig_y = y;
 200
 201         pos = (x + cols * y) * 2;       /* Update cursor position */
 202         outb_p(14, vidport);
 203         outb_p(0xff & (pos >> 9), vidport+1);
 204         outb_p(15, vidport);
 205         outb_p(0xff & (pos >> 1), vidport+1);
 206 }
 207
 208 static void* memset(void* s, int c, size_t n)
 209 {
 210         int i;
 211         char *ss = (char*)s;
 212
 213         for (i=0;i<n;i++) ss[i] = c;
 214         return s;
 215 }
 216
 217 static void* memcpy(void* __dest, __const void* __src,
 218                             size_t __n)
 219 {
 220         int i;
 221         char *d = (char *)__dest, *s = (char *)__src;
 222
 223         for (i=0;i<__n;i++) d[i] = s[i];
 224         return __dest;
 225 }
 226
 227 /* ===========================================================================
 228  * Fill the input buffer. This is called only when the buffer is empty
 229  * and at least one byte is really needed.
 230  */
 231 static int fill_inbuf(void)
 232 {
 233         if (insize != 0) {
 234                 error("ran out of input data");
 235         }
 236
 237         inbuf = input_data;
 238         insize = input_len;
 239         inptr = 1;
 240         return inbuf[0];
 241 }
 242
 243 /* ===========================================================================
 244  * Write the output window window[0..outcnt-1] and update crc and bytes_out.
 245  * (Used for the decompressed data only.)
 246  */
 247 static void flush_window_low(void)
 248 {
 249     ulg c = crc;         /* temporary variable */
 250     unsigned n;
 251     uch *in, *out, ch;
 252
 253     in = window;
 254     out = &output_data[output_ptr];
 255     for (n = 0; n < outcnt; n++) {
 256             ch = *out++ = *in++;
 257             c = crc_32_tab[((int)c ^ ch) & 0xff] ^ (c >> 8);
 258     }
 259     crc = c;
 260     bytes_out += (ulg)outcnt;
 261     output_ptr += (ulg)outcnt;
 262     outcnt = 0;
 263 }
 264
 265 static void flush_window_high(void)
 266 {
 267     ulg c = crc;         /* temporary variable */
 268     unsigned n;
 269     uch *in,  ch;
 270     in = window;
 271     for (n = 0; n < outcnt; n++) {
 272         ch = *output_data++ = *in++;
 273         if ((ulg)output_data == low_buffer_end) output_data=high_buffer_start;
 274         c = crc_32_tab[((int)c ^ ch) & 0xff] ^ (c >> 8);
 275     }
 276     crc = c;
 277     bytes_out += (ulg)outcnt;
 278     outcnt = 0;
 279 }
 280
 281 static void flush_window(void)
 282 {
 283         if (high_loaded) flush_window_high();
 284         else flush_window_low();
 285 }
 286
 287 static void error(char *x)
 288 {
 289         putstr("\n\n");
 290         putstr(x);
 291         putstr("\n\n -- System halted");
 292
 293         while(1);       /* Halt */
 294 }
 295
 296 #define STACK_SIZE (4096)
 297
 298 long user_stack [STACK_SIZE];
 299
 300 struct {
 301         long * a;
 302         short b;
 303         } stack_start = { & user_stack [STACK_SIZE] , __BOOT_DS };
 304
 305 static void setup_normal_output_buffer(void)
 306 {
 307 #ifdef STANDARD_MEMORY_BIOS_CALL
 308         if (RM_EXT_MEM_K < 1024) error("Less than 2MB of memory");
 309 #else
 310         if ((RM_ALT_MEM_K > RM_EXT_MEM_K ? RM_ALT_MEM_K : RM_EXT_MEM_K) < 1024) error("Less than 2MB of memory");
 311 #endif
 312         output_data = (char *)0x100000; /* Points to 1M */
 313         free_mem_end_ptr = (long)real_mode;
 314 }
 315
 316 struct moveparams {
 317         uch *low_buffer_start;  int lcount;
 318         uch *high_buffer_start; int hcount;
 319 };
 320
 321 static void setup_output_buffer_if_we_run_high(struct moveparams *mv)
 322 {
 323         high_buffer_start = (uch *)(((ulg)&end) + HEAP_SIZE);
 324 #ifdef STANDARD_MEMORY_BIOS_CALL
 325         if (RM_EXT_MEM_K < (3*1024)) error("Less than 4MB of memory");
 326 #else
 327         if ((RM_ALT_MEM_K > RM_EXT_MEM_K ? RM_ALT_MEM_K : RM_EXT_MEM_K) <
 328                         (3*1024))
 329                 error("Less than 4MB of memory");
 330 #endif
 331         mv->low_buffer_start = output_data = (char *)LOW_BUFFER_START;
 332         low_buffer_end = ((unsigned int)real_mode > LOW_BUFFER_MAX
 333           ? LOW_BUFFER_MAX : (unsigned int)real_mode) & ~0xfff;
 334         low_buffer_size = low_buffer_end - LOW_BUFFER_START;
 335         high_loaded = 1;
 336         free_mem_end_ptr = (long)high_buffer_start;
 337         if ( (0x100000 + low_buffer_size) > ((ulg)high_buffer_start)) {
 338                 high_buffer_start = (uch *)(0x100000 + low_buffer_size);
 339                 mv->hcount = 0; /* say: we need not to move high_buffer */
 340         }
 341         else mv->hcount = -1;
 342         mv->high_buffer_start = high_buffer_start;
 343 }
 344
 345 static void close_output_buffer_if_we_run_high(struct moveparams *mv)
 346 {
 347         if (bytes_out > low_buffer_size) {
 348                 mv->lcount = low_buffer_size;
 349                 if (mv->hcount)
 350                         mv->hcount = bytes_out - low_buffer_size;
 351         } else {
 352                 mv->lcount = bytes_out;
 353                 mv->hcount = 0;
 354         }
 355 }
 356
 357
 358 asmlinkage int decompress_kernel(struct moveparams *mv, void *rmode)
 359 {
 360         real_mode = rmode;
 361
 362         if (RM_SCREEN_INFO.orig_video_mode == 7) {
 363                 vidmem = (char *) 0xb0000;
 364                 vidport = 0x3b4;
 365         } else {
 366                 vidmem = (char *) 0xb8000;
 367                 vidport = 0x3d4;
 368         }
 369
 370         lines = RM_SCREEN_INFO.orig_video_lines;
 371         cols = RM_SCREEN_INFO.orig_video_cols;
 372
 373         if (free_mem_ptr < 0x100000) setup_normal_output_buffer();
 374         else setup_output_buffer_if_we_run_high(mv);
 375
 376         makecrc();
 377         putstr("Uncompressing Linux... ");
 378         gunzip();
 379         putstr("Ok, booting the kernel.\n");
 380         if (high_loaded) close_output_buffer_if_we_run_high(mv);
 381         return high_loaded;
 382 }