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/screen_info.h>
  15 #include <asm/io.h>
  16 #include <asm/page.h>
  17
  18 #undef  __BOOT_CS
  19 #define __BOOT_CS       0x10
  20 #undef  __BOOT_DS
  21 #define __BOOT_DS       0x18
  22
  23 /*
  24  * gzip declarations
  25  */
  26
  27 #define OF(args)  args
  28 #define STATIC static
  29
  30 #undef memset
  31 #undef memcpy
  32 #define memzero(s, n)     memset ((s), 0, (n))
  33
  34 typedef unsigned char  uch;
  35 typedef unsigned short ush;
  36 typedef unsigned long  ulg;
  37
  38 #define WSIZE 0x8000            /* Window size must be at least 32k, */
  39                                 /* and a power of two */
  40
  41 static uch *inbuf;           /* input buffer */
  42 static uch window[WSIZE];    /* Sliding window buffer */
  43
  44 static unsigned insize = 0;  /* valid bytes in inbuf */
  45 static unsigned inptr = 0;   /* index of next byte to be processed in inbuf */
  46 static unsigned outcnt = 0;  /* bytes in output buffer */
  47
  48 /* gzip flag byte */
  49 #define ASCII_FLAG   0x01 /* bit 0 set: file probably ASCII text */
  50 #define CONTINUATION 0x02 /* bit 1 set: continuation of multi-part gzip file */
  51 #define EXTRA_FIELD  0x04 /* bit 2 set: extra field present */
  52 #define ORIG_NAME    0x08 /* bit 3 set: original file name present */
  53 #define COMMENT      0x10 /* bit 4 set: file comment present */
  54 #define ENCRYPTED    0x20 /* bit 5 set: file is encrypted */
  55 #define RESERVED     0xC0 /* bit 6,7:   reserved */
  56
  57 #define get_byte()  (inptr < insize ? inbuf[inptr++] : fill_inbuf())
  58
  59 /* Diagnostic functions */
  60 #ifdef DEBUG
  61 #  define Assert(cond,msg) {if(!(cond)) error(msg);}
  62 #  define Trace(x) fprintf x
  63 #  define Tracev(x) {if (verbose) fprintf x ;}
  64 #  define Tracevv(x) {if (verbose>1) fprintf x ;}
  65 #  define Tracec(c,x) {if (verbose && (c)) fprintf x ;}
  66 #  define Tracecv(c,x) {if (verbose>1 && (c)) fprintf x ;}
  67 #else
  68 #  define Assert(cond,msg)
  69 #  define Trace(x)
  70 #  define Tracev(x)
  71 #  define Tracevv(x)
  72 #  define Tracec(c,x)
  73 #  define Tracecv(c,x)
  74 #endif
  75
  76 static int  fill_inbuf(void);
  77 static void flush_window(void);
  78 static void error(char *m);
  79 static void gzip_mark(void **);
  80 static void gzip_release(void **);
  81
  82 /*
  83  * This is set up by the setup-routine at boot-time
  84  */
  85 static unsigned char *real_mode; /* Pointer to real-mode data */
  86
  87 #define RM_EXT_MEM_K   (*(unsigned short *)(real_mode + 0x2))
  88 #ifndef STANDARD_MEMORY_BIOS_CALL
  89 #define RM_ALT_MEM_K   (*(unsigned long *)(real_mode + 0x1e0))
  90 #endif
  91 #define RM_SCREEN_INFO (*(struct screen_info *)(real_mode+0))
  92
  93 extern unsigned char input_data[];
  94 extern int input_len;
  95
  96 static long bytes_out = 0;
  97 static uch *output_data;
  98 static unsigned long output_ptr = 0;
  99
 100 static void *malloc(int size);
 101 static void free(void *where);
 102
 103 static void *memset(void *s, int c, unsigned n);
 104 static void *memcpy(void *dest, const void *src, unsigned n);
 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, unsigned 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, unsigned n)
 218 {
 219         int i;
 220         char *d = (char *)dest, *s = (char *)src;
 221
 222         for (i=0;i<n;i++) d[i] = s[i];
 223         return dest;
 224 }
 225
 226 /* ===========================================================================
 227  * Fill the input buffer. This is called only when the buffer is empty
 228  * and at least one byte is really needed.
 229  */
 230 static int fill_inbuf(void)
 231 {
 232         if (insize != 0) {
 233                 error("ran out of input data");
 234         }
 235
 236         inbuf = input_data;
 237         insize = input_len;
 238         inptr = 1;
 239         return inbuf[0];
 240 }
 241
 242 /* ===========================================================================
 243  * Write the output window window[0..outcnt-1] and update crc and bytes_out.
 244  * (Used for the decompressed data only.)
 245  */
 246 static void flush_window_low(void)
 247 {
 248     ulg c = crc;         /* temporary variable */
 249     unsigned n;
 250     uch *in, *out, ch;
 251
 252     in = window;
 253     out = &output_data[output_ptr];
 254     for (n = 0; n < outcnt; n++) {
 255             ch = *out++ = *in++;
 256             c = crc_32_tab[((int)c ^ ch) & 0xff] ^ (c >> 8);
 257     }
 258     crc = c;
 259     bytes_out += (ulg)outcnt;
 260     output_ptr += (ulg)outcnt;
 261     outcnt = 0;
 262 }
 263
 264 static void flush_window_high(void)
 265 {
 266     ulg c = crc;         /* temporary variable */
 267     unsigned n;
 268     uch *in,  ch;
 269     in = window;
 270     for (n = 0; n < outcnt; n++) {
 271         ch = *output_data++ = *in++;
 272         if ((ulg)output_data == low_buffer_end) output_data=high_buffer_start;
 273         c = crc_32_tab[((int)c ^ ch) & 0xff] ^ (c >> 8);
 274     }
 275     crc = c;
 276     bytes_out += (ulg)outcnt;
 277     outcnt = 0;
 278 }
 279
 280 static void flush_window(void)
 281 {
 282         if (high_loaded) flush_window_high();
 283         else flush_window_low();
 284 }
 285
 286 static void error(char *x)
 287 {
 288         putstr("\n\n");
 289         putstr(x);
 290         putstr("\n\n -- System halted");
 291
 292         while(1);       /* Halt */
 293 }
 294
 295 #define STACK_SIZE (4096)
 296
 297 long user_stack [STACK_SIZE];
 298
 299 struct {
 300         long * a;
 301         short b;
 302         } stack_start = { & user_stack [STACK_SIZE] , __BOOT_DS };
 303
 304 static void setup_normal_output_buffer(void)
 305 {
 306 #ifdef STANDARD_MEMORY_BIOS_CALL
 307         if (RM_EXT_MEM_K < 1024) error("Less than 2MB of memory");
 308 #else
 309         if ((RM_ALT_MEM_K > RM_EXT_MEM_K ? RM_ALT_MEM_K : RM_EXT_MEM_K) < 1024) error("Less than 2MB of memory");
 310 #endif
 311         output_data = (unsigned char *)__PHYSICAL_START; /* Normally Points to 1M */
 312         free_mem_end_ptr = (long)real_mode;
 313 }
 314
 315 struct moveparams {
 316         uch *low_buffer_start;  int lcount;
 317         uch *high_buffer_start; int hcount;
 318 };
 319
 320 static void setup_output_buffer_if_we_run_high(struct moveparams *mv)
 321 {
 322         high_buffer_start = (uch *)(((ulg)&end) + HEAP_SIZE);
 323 #ifdef STANDARD_MEMORY_BIOS_CALL
 324         if (RM_EXT_MEM_K < (3*1024)) error("Less than 4MB of memory");
 325 #else
 326         if ((RM_ALT_MEM_K > RM_EXT_MEM_K ? RM_ALT_MEM_K : RM_EXT_MEM_K) < (3*1024)) error("Less than 4MB of memory");
 327 #endif
 328         mv->low_buffer_start = output_data = (unsigned char *)LOW_BUFFER_START;
 329         low_buffer_end = ((unsigned int)real_mode > LOW_BUFFER_MAX
 330           ? LOW_BUFFER_MAX : (unsigned int)real_mode) & ~0xfff;
 331         low_buffer_size = low_buffer_end - LOW_BUFFER_START;
 332         high_loaded = 1;
 333         free_mem_end_ptr = (long)high_buffer_start;
 334         if ( (__PHYSICAL_START + low_buffer_size) > ((ulg)high_buffer_start)) {
 335                 high_buffer_start = (uch *)(__PHYSICAL_START + low_buffer_size);
 336                 mv->hcount = 0; /* say: we need not to move high_buffer */
 337         }
 338         else mv->hcount = -1;
 339         mv->high_buffer_start = high_buffer_start;
 340 }
 341
 342 static void close_output_buffer_if_we_run_high(struct moveparams *mv)
 343 {
 344         if (bytes_out > low_buffer_size) {
 345                 mv->lcount = low_buffer_size;
 346                 if (mv->hcount)
 347                         mv->hcount = bytes_out - low_buffer_size;
 348         } else {
 349                 mv->lcount = bytes_out;
 350                 mv->hcount = 0;
 351         }
 352 }
 353
 354 asmlinkage int decompress_kernel(struct moveparams *mv, void *rmode)
 355 {
 356         real_mode = rmode;
 357
 358         if (RM_SCREEN_INFO.orig_video_mode == 7) {
 359                 vidmem = (char *) 0xb0000;
 360                 vidport = 0x3b4;
 361         } else {
 362                 vidmem = (char *) 0xb8000;
 363                 vidport = 0x3d4;
 364         }
 365
 366         lines = RM_SCREEN_INFO.orig_video_lines;
 367         cols = RM_SCREEN_INFO.orig_video_cols;
 368
 369         if (free_mem_ptr < 0x100000) setup_normal_output_buffer();
 370         else setup_output_buffer_if_we_run_high(mv);
 371
 372         makecrc();
 373         putstr("Uncompressing Linux... ");
 374         gunzip();
 375         putstr("Ok, booting the kernel.\n");
 376         if (high_loaded) close_output_buffer_if_we_run_high(mv);
 377         return high_loaded;
 378 }