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   1 /*
   2  *  linux/drivers/video/vgacon.c -- Low level VGA based console driver
   3  *
   4  *      Created 28 Sep 1997 by Geert Uytterhoeven
   5  *
   6  *      Rewritten by Martin Mares <mj@ucw.cz>, July 1998
   7  *
   8  *  This file is based on the old console.c, vga.c and vesa_blank.c drivers.
   9  *
  10  *      Copyright (C) 1991, 1992  Linus Torvalds
  11  *                          1995  Jay Estabrook
  12  *
  13  *      User definable mapping table and font loading by Eugene G. Crosser,
  14  *      <crosser@average.org>
  15  *
  16  *      Improved loadable font/UTF-8 support by H. Peter Anvin
  17  *      Feb-Sep 1995 <peter.anvin@linux.org>
  18  *
  19  *      Colour palette handling, by Simon Tatham
  20  *      17-Jun-95 <sgt20@cam.ac.uk>
  21  *
  22  *      if 512 char mode is already enabled don't re-enable it,
  23  *      because it causes screen to flicker, by Mitja Horvat
  24  *      5-May-96 <mitja.horvat@guest.arnes.si>
  25  *
  26  *      Use 2 outw instead of 4 outb_p to reduce erroneous text
  27  *      flashing on RHS of screen during heavy console scrolling .
  28  *      Oct 1996, Paul Gortmaker.
  29  *
  30  *
  31  *  This file is subject to the terms and conditions of the GNU General Public
  32  *  License.  See the file COPYING in the main directory of this archive for
  33  *  more details.
  34  */
  35
  36 #include <linux/config.h>
  37 #include <linux/module.h>
  38 #include <linux/types.h>
  39 #include <linux/sched.h>
  40 #include <linux/fs.h>
  41 #include <linux/kernel.h>
  42 #include <linux/tty.h>
  43 #include <linux/console.h>
  44 #include <linux/string.h>
  45 #include <linux/kd.h>
  46 #include <linux/slab.h>
  47 #include <linux/vt_kern.h>
  48 #include <linux/selection.h>
  49 #include <linux/spinlock.h>
  50 #include <linux/ioport.h>
  51 #include <linux/init.h>
  52 #include <linux/smp_lock.h>
  53 #include <video/vga.h>
  54 #include <asm/io.h>
  55
  56 static DEFINE_SPINLOCK(vga_lock);
  57 static int cursor_size_lastfrom;
  58 static int cursor_size_lastto;
  59 static struct vgastate state;
  60
  61 #define BLANK 0x0020
  62
  63 #define CAN_LOAD_EGA_FONTS      /* undefine if the user must not do this */
  64 #define CAN_LOAD_PALETTE        /* undefine if the user must not do this */
  65
  66 /* You really do _NOT_ want to define this, unless you have buggy
  67  * Trident VGA which will resize cursor when moving it between column
  68  * 15 & 16. If you define this and your VGA is OK, inverse bug will
  69  * appear.
  70  */
  71 #undef TRIDENT_GLITCH
  72
  73 /*
  74  *  Interface used by the world
  75  */
  76
  77 static const char *vgacon_startup(void);
  78 static void vgacon_init(struct vc_data *c, int init);
  79 static void vgacon_deinit(struct vc_data *c);
  80 static void vgacon_cursor(struct vc_data *c, int mode);
  81 static int vgacon_switch(struct vc_data *c);
  82 static int vgacon_blank(struct vc_data *c, int blank, int mode_switch);
  83 static int vgacon_set_palette(struct vc_data *vc, unsigned char *table);
  84 static int vgacon_scrolldelta(struct vc_data *c, int lines);
  85 static int vgacon_set_origin(struct vc_data *c);
  86 static void vgacon_save_screen(struct vc_data *c);
  87 static int vgacon_scroll(struct vc_data *c, int t, int b, int dir,
  88                          int lines);
  89 static u8 vgacon_build_attr(struct vc_data *c, u8 color, u8 intensity,
  90                             u8 blink, u8 underline, u8 reverse);
  91 static void vgacon_invert_region(struct vc_data *c, u16 * p, int count);
  92 static unsigned long vgacon_uni_pagedir[2];
  93
  94
  95 /* Description of the hardware situation */
  96 static unsigned long    vga_vram_base;          /* Base of video memory */
  97 static unsigned long    vga_vram_end;           /* End of video memory */
  98 static int              vga_vram_size;          /* Size of video memory */
  99 static u16              vga_video_port_reg;     /* Video register select port */
 100 static u16              vga_video_port_val;     /* Video register value port */
 101 static unsigned int     vga_video_num_columns;  /* Number of text columns */
 102 static unsigned int     vga_video_num_lines;    /* Number of text lines */
 103 static int              vga_can_do_color = 0;   /* Do we support colors? */
 104 static unsigned int     vga_default_font_height;/* Height of default screen font */
 105 static unsigned char    vga_video_type;         /* Card type */
 106 static unsigned char    vga_hardscroll_enabled;
 107 static unsigned char    vga_hardscroll_user_enable = 1;
 108 static unsigned char    vga_font_is_default = 1;
 109 static int              vga_vesa_blanked;
 110 static int              vga_palette_blanked;
 111 static int              vga_is_gfx;
 112 static int              vga_512_chars;
 113 static int              vga_video_font_height;
 114 static int              vga_scan_lines;
 115 static unsigned int     vga_rolled_over = 0;
 116
 117 static int __init no_scroll(char *str)
 118 {
 119         /*
 120          * Disabling scrollback is required for the Braillex ib80-piezo
 121          * Braille reader made by F.H. Papenmeier (Germany).
 122          * Use the "no-scroll" bootflag.
 123          */
 124         vga_hardscroll_user_enable = vga_hardscroll_enabled = 0;
 125         return 1;
 126 }
 127
 128 __setup("no-scroll", no_scroll);
 129
 130 /*
 131  * By replacing the four outb_p with two back to back outw, we can reduce
 132  * the window of opportunity to see text mislocated to the RHS of the
 133  * console during heavy scrolling activity. However there is the remote
 134  * possibility that some pre-dinosaur hardware won't like the back to back
 135  * I/O. Since the Xservers get away with it, we should be able to as well.
 136  */
 137 static inline void write_vga(unsigned char reg, unsigned int val)
 138 {
 139         unsigned int v1, v2;
 140         unsigned long flags;
 141
 142         /*
 143          * ddprintk might set the console position from interrupt
 144          * handlers, thus the write has to be IRQ-atomic.
 145          */
 146         spin_lock_irqsave(&vga_lock, flags);
 147
 148 #ifndef SLOW_VGA
 149         v1 = reg + (val & 0xff00);
 150         v2 = reg + 1 + ((val << 8) & 0xff00);
 151         outw(v1, vga_video_port_reg);
 152         outw(v2, vga_video_port_reg);
 153 #else
 154         outb_p(reg, vga_video_port_reg);
 155         outb_p(val >> 8, vga_video_port_val);
 156         outb_p(reg + 1, vga_video_port_reg);
 157         outb_p(val & 0xff, vga_video_port_val);
 158 #endif
 159         spin_unlock_irqrestore(&vga_lock, flags);
 160 }
 161
 162 static const char __init *vgacon_startup(void)
 163 {
 164         const char *display_desc = NULL;
 165         u16 saved1, saved2;
 166         volatile u16 *p;
 167
 168         if (ORIG_VIDEO_ISVGA == VIDEO_TYPE_VLFB) {
 169               no_vga:
 170 #ifdef CONFIG_DUMMY_CONSOLE
 171                 conswitchp = &dummy_con;
 172                 return conswitchp->con_startup();
 173 #else
 174                 return NULL;
 175 #endif
 176         }
 177
 178         /* VGA16 modes are not handled by VGACON */
 179         if ((ORIG_VIDEO_MODE == 0x0D) ||        /* 320x200/4 */
 180             (ORIG_VIDEO_MODE == 0x0E) ||        /* 640x200/4 */
 181             (ORIG_VIDEO_MODE == 0x10) ||        /* 640x350/4 */
 182             (ORIG_VIDEO_MODE == 0x12) ||        /* 640x480/4 */
 183             (ORIG_VIDEO_MODE == 0x6A))  /* 800x600/4, 0x6A is very common */
 184                 goto no_vga;
 185
 186         vga_video_num_lines = ORIG_VIDEO_LINES;
 187         vga_video_num_columns = ORIG_VIDEO_COLS;
 188         state.vgabase = NULL;
 189
 190         if (ORIG_VIDEO_MODE == 7) {     /* Is this a monochrome display? */
 191                 vga_vram_base = 0xb0000;
 192                 vga_video_port_reg = VGA_CRT_IM;
 193                 vga_video_port_val = VGA_CRT_DM;
 194                 if ((ORIG_VIDEO_EGA_BX & 0xff) != 0x10) {
 195                         static struct resource ega_console_resource =
 196                             { "ega", 0x3B0, 0x3BF };
 197                         vga_video_type = VIDEO_TYPE_EGAM;
 198                         vga_vram_end = 0xb8000;
 199                         display_desc = "EGA+";
 200                         request_resource(&ioport_resource,
 201                                          &ega_console_resource);
 202                 } else {
 203                         static struct resource mda1_console_resource =
 204                             { "mda", 0x3B0, 0x3BB };
 205                         static struct resource mda2_console_resource =
 206                             { "mda", 0x3BF, 0x3BF };
 207                         vga_video_type = VIDEO_TYPE_MDA;
 208                         vga_vram_end = 0xb2000;
 209                         display_desc = "*MDA";
 210                         request_resource(&ioport_resource,
 211                                          &mda1_console_resource);
 212                         request_resource(&ioport_resource,
 213                                          &mda2_console_resource);
 214                         vga_video_font_height = 14;
 215                 }
 216         } else {
 217                 /* If not, it is color. */
 218                 vga_can_do_color = 1;
 219                 vga_vram_base = 0xb8000;
 220                 vga_video_port_reg = VGA_CRT_IC;
 221                 vga_video_port_val = VGA_CRT_DC;
 222                 if ((ORIG_VIDEO_EGA_BX & 0xff) != 0x10) {
 223                         int i;
 224
 225                         vga_vram_end = 0xc0000;
 226
 227                         if (!ORIG_VIDEO_ISVGA) {
 228                                 static struct resource ega_console_resource
 229                                     = { "ega", 0x3C0, 0x3DF };
 230                                 vga_video_type = VIDEO_TYPE_EGAC;
 231                                 display_desc = "EGA";
 232                                 request_resource(&ioport_resource,
 233                                                  &ega_console_resource);
 234                         } else {
 235                                 static struct resource vga_console_resource
 236                                     = { "vga+", 0x3C0, 0x3DF };
 237                                 vga_video_type = VIDEO_TYPE_VGAC;
 238                                 display_desc = "VGA+";
 239                                 request_resource(&ioport_resource,
 240                                                  &vga_console_resource);
 241
 242 #ifdef VGA_CAN_DO_64KB
 243                                 /*
 244                                  * get 64K rather than 32K of video RAM.
 245                                  * This doesn't actually work on all "VGA"
 246                                  * controllers (it seems like setting MM=01
 247                                  * and COE=1 isn't necessarily a good idea)
 248                                  */
 249                                 vga_vram_base = 0xa0000;
 250                                 vga_vram_end = 0xb0000;
 251                                 outb_p(6, VGA_GFX_I);
 252                                 outb_p(6, VGA_GFX_D);
 253 #endif
 254                                 /*
 255                                  * Normalise the palette registers, to point
 256                                  * the 16 screen colours to the first 16
 257                                  * DAC entries.
 258                                  */
 259
 260                                 for (i = 0; i < 16; i++) {
 261                                         inb_p(VGA_IS1_RC);
 262                                         outb_p(i, VGA_ATT_W);
 263                                         outb_p(i, VGA_ATT_W);
 264                                 }
 265                                 outb_p(0x20, VGA_ATT_W);
 266
 267                                 /*
 268                                  * Now set the DAC registers back to their
 269                                  * default values
 270                                  */
 271                                 for (i = 0; i < 16; i++) {
 272                                         outb_p(color_table[i], VGA_PEL_IW);
 273                                         outb_p(default_red[i], VGA_PEL_D);
 274                                         outb_p(default_grn[i], VGA_PEL_D);
 275                                         outb_p(default_blu[i], VGA_PEL_D);
 276                                 }
 277                         }
 278                 } else {
 279                         static struct resource cga_console_resource =
 280                             { "cga", 0x3D4, 0x3D5 };
 281                         vga_video_type = VIDEO_TYPE_CGA;
 282                         vga_vram_end = 0xba000;
 283                         display_desc = "*CGA";
 284                         request_resource(&ioport_resource,
 285                                          &cga_console_resource);
 286                         vga_video_font_height = 8;
 287                 }
 288         }
 289
 290         vga_vram_base = VGA_MAP_MEM(vga_vram_base);
 291         vga_vram_end = VGA_MAP_MEM(vga_vram_end);
 292         vga_vram_size = vga_vram_end - vga_vram_base;
 293
 294         /*
 295          *      Find out if there is a graphics card present.
 296          *      Are there smarter methods around?
 297          */
 298         p = (volatile u16 *) vga_vram_base;
 299         saved1 = scr_readw(p);
 300         saved2 = scr_readw(p + 1);
 301         scr_writew(0xAA55, p);
 302         scr_writew(0x55AA, p + 1);
 303         if (scr_readw(p) != 0xAA55 || scr_readw(p + 1) != 0x55AA) {
 304                 scr_writew(saved1, p);
 305                 scr_writew(saved2, p + 1);
 306                 goto no_vga;
 307         }
 308         scr_writew(0x55AA, p);
 309         scr_writew(0xAA55, p + 1);
 310         if (scr_readw(p) != 0x55AA || scr_readw(p + 1) != 0xAA55) {
 311                 scr_writew(saved1, p);
 312                 scr_writew(saved2, p + 1);
 313                 goto no_vga;
 314         }
 315         scr_writew(saved1, p);
 316         scr_writew(saved2, p + 1);
 317
 318         if (vga_video_type == VIDEO_TYPE_EGAC
 319             || vga_video_type == VIDEO_TYPE_VGAC
 320             || vga_video_type == VIDEO_TYPE_EGAM) {
 321                 vga_hardscroll_enabled = vga_hardscroll_user_enable;
 322                 vga_default_font_height = ORIG_VIDEO_POINTS;
 323                 vga_video_font_height = ORIG_VIDEO_POINTS;
 324                 /* This may be suboptimal but is a safe bet - go with it */
 325                 vga_scan_lines =
 326                     vga_video_font_height * vga_video_num_lines;
 327         }
 328         return display_desc;
 329 }
 330
 331 static void vgacon_init(struct vc_data *c, int init)
 332 {
 333         unsigned long p;
 334
 335         /* We cannot be loaded as a module, therefore init is always 1 */
 336         c->vc_can_do_color = vga_can_do_color;
 337         c->vc_cols = vga_video_num_columns;
 338         c->vc_rows = vga_video_num_lines;
 339         c->vc_scan_lines = vga_scan_lines;
 340         c->vc_font.height = vga_video_font_height;
 341         c->vc_complement_mask = 0x7700;
 342         if (vga_512_chars)
 343                 c->vc_hi_font_mask = 0x0800;
 344         p = *c->vc_uni_pagedir_loc;
 345         if (c->vc_uni_pagedir_loc == &c->vc_uni_pagedir ||
 346             !--c->vc_uni_pagedir_loc[1])
 347                 con_free_unimap(c);
 348         c->vc_uni_pagedir_loc = vgacon_uni_pagedir;
 349         vgacon_uni_pagedir[1]++;
 350         if (!vgacon_uni_pagedir[0] && p)
 351                 con_set_default_unimap(c);
 352 }
 353
 354 static inline void vga_set_mem_top(struct vc_data *c)
 355 {
 356         write_vga(12, (c->vc_visible_origin - vga_vram_base) / 2);
 357 }
 358
 359 static void vgacon_deinit(struct vc_data *c)
 360 {
 361         /* When closing the last console, reset video origin */
 362         if (!--vgacon_uni_pagedir[1]) {
 363                 c->vc_visible_origin = vga_vram_base;
 364                 vga_set_mem_top(c);
 365                 con_free_unimap(c);
 366         }
 367         c->vc_uni_pagedir_loc = &c->vc_uni_pagedir;
 368         con_set_default_unimap(c);
 369 }
 370
 371 static u8 vgacon_build_attr(struct vc_data *c, u8 color, u8 intensity,
 372                             u8 blink, u8 underline, u8 reverse)
 373 {
 374         u8 attr = color;
 375
 376         if (vga_can_do_color) {
 377                 if (underline)
 378                         attr = (attr & 0xf0) | c->vc_ulcolor;
 379                 else if (intensity == 0)
 380                         attr = (attr & 0xf0) | c->vc_halfcolor;
 381         }
 382         if (reverse)
 383                 attr =
 384                     ((attr) & 0x88) | ((((attr) >> 4) | ((attr) << 4)) &
 385                                        0x77);
 386         if (blink)
 387                 attr ^= 0x80;
 388         if (intensity == 2)
 389                 attr ^= 0x08;
 390         if (!vga_can_do_color) {
 391                 if (underline)
 392                         attr = (attr & 0xf8) | 0x01;
 393                 else if (intensity == 0)
 394                         attr = (attr & 0xf0) | 0x08;
 395         }
 396         return attr;
 397 }
 398
 399 static void vgacon_invert_region(struct vc_data *c, u16 * p, int count)
 400 {
 401         int col = vga_can_do_color;
 402
 403         while (count--) {
 404                 u16 a = scr_readw(p);
 405                 if (col)
 406                         a = ((a) & 0x88ff) | (((a) & 0x7000) >> 4) |
 407                             (((a) & 0x0700) << 4);
 408                 else
 409                         a ^= ((a & 0x0700) == 0x0100) ? 0x7000 : 0x7700;
 410                 scr_writew(a, p++);
 411         }
 412 }
 413
 414 static void vgacon_set_cursor_size(int xpos, int from, int to)
 415 {
 416         unsigned long flags;
 417         int curs, cure;
 418
 419 #ifdef TRIDENT_GLITCH
 420         if (xpos < 16)
 421                 from--, to--;
 422 #endif
 423
 424         if ((from == cursor_size_lastfrom) && (to == cursor_size_lastto))
 425                 return;
 426         cursor_size_lastfrom = from;
 427         cursor_size_lastto = to;
 428
 429         spin_lock_irqsave(&vga_lock, flags);
 430         outb_p(0x0a, vga_video_port_reg);       /* Cursor start */
 431         curs = inb_p(vga_video_port_val);
 432         outb_p(0x0b, vga_video_port_reg);       /* Cursor end */
 433         cure = inb_p(vga_video_port_val);
 434
 435         curs = (curs & 0xc0) | from;
 436         cure = (cure & 0xe0) | to;
 437
 438         outb_p(0x0a, vga_video_port_reg);       /* Cursor start */
 439         outb_p(curs, vga_video_port_val);
 440         outb_p(0x0b, vga_video_port_reg);       /* Cursor end */
 441         outb_p(cure, vga_video_port_val);
 442         spin_unlock_irqrestore(&vga_lock, flags);
 443 }
 444
 445 static void vgacon_cursor(struct vc_data *c, int mode)
 446 {
 447         if (c->vc_origin != c->vc_visible_origin)
 448                 vgacon_scrolldelta(c, 0);
 449         switch (mode) {
 450         case CM_ERASE:
 451                 write_vga(14, (vga_vram_end - vga_vram_base - 1) / 2);
 452                 break;
 453
 454         case CM_MOVE:
 455         case CM_DRAW:
 456                 write_vga(14, (c->vc_pos - vga_vram_base) / 2);
 457                 switch (c->vc_cursor_type & 0x0f) {
 458                 case CUR_UNDERLINE:
 459                         vgacon_set_cursor_size(c->vc_x,
 460                                                c->vc_font.height -
 461                                                (c->vc_font.height <
 462                                                 10 ? 2 : 3),
 463                                                c->vc_font.height -
 464                                                (c->vc_font.height <
 465                                                 10 ? 1 : 2));
 466                         break;
 467                 case CUR_TWO_THIRDS:
 468                         vgacon_set_cursor_size(c->vc_x,
 469                                                c->vc_font.height / 3,
 470                                                c->vc_font.height -
 471                                                (c->vc_font.height <
 472                                                 10 ? 1 : 2));
 473                         break;
 474                 case CUR_LOWER_THIRD:
 475                         vgacon_set_cursor_size(c->vc_x,
 476                                                (c->vc_font.height * 2) / 3,
 477                                                c->vc_font.height -
 478                                                (c->vc_font.height <
 479                                                 10 ? 1 : 2));
 480                         break;
 481                 case CUR_LOWER_HALF:
 482                         vgacon_set_cursor_size(c->vc_x,
 483                                                c->vc_font.height / 2,
 484                                                c->vc_font.height -
 485                                                (c->vc_font.height <
 486                                                 10 ? 1 : 2));
 487                         break;
 488                 case CUR_NONE:
 489                         vgacon_set_cursor_size(c->vc_x, 31, 30);
 490                         break;
 491                 default:
 492                         vgacon_set_cursor_size(c->vc_x, 1,
 493                                                c->vc_font.height);
 494                         break;
 495                 }
 496                 break;
 497         }
 498 }
 499
 500 static int vgacon_doresize(struct vc_data *c,
 501                 unsigned int width, unsigned int height)
 502 {
 503         unsigned long flags;
 504         unsigned int scanlines = height * c->vc_font.height;
 505         u8 scanlines_lo, r7, vsync_end, mode;
 506
 507         spin_lock_irqsave(&vga_lock, flags);
 508
 509         outb_p(VGA_CRTC_MODE, vga_video_port_reg);
 510         mode = inb_p(vga_video_port_val);
 511
 512         if (mode & 0x04)
 513                 scanlines >>= 1;
 514
 515         scanlines -= 1;
 516         scanlines_lo = scanlines & 0xff;
 517
 518         outb_p(VGA_CRTC_OVERFLOW, vga_video_port_reg);
 519         r7 = inb_p(vga_video_port_val) & ~0x42;
 520
 521         if (scanlines & 0x100)
 522                 r7 |= 0x02;
 523         if (scanlines & 0x200)
 524                 r7 |= 0x40;
 525
 526         /* deprotect registers */
 527         outb_p(VGA_CRTC_V_SYNC_END, vga_video_port_reg);
 528         vsync_end = inb_p(vga_video_port_val);
 529         outb_p(VGA_CRTC_V_SYNC_END, vga_video_port_reg);
 530         outb_p(vsync_end & ~0x80, vga_video_port_val);
 531
 532         outb_p(VGA_CRTC_H_DISP, vga_video_port_reg);
 533         outb_p(width - 1, vga_video_port_val);
 534         outb_p(VGA_CRTC_OFFSET, vga_video_port_reg);
 535         outb_p(width >> 1, vga_video_port_val);
 536
 537         outb_p(VGA_CRTC_V_DISP_END, vga_video_port_reg);
 538         outb_p(scanlines_lo, vga_video_port_val);
 539         outb_p(VGA_CRTC_OVERFLOW, vga_video_port_reg);
 540         outb_p(r7,vga_video_port_val);
 541
 542         /* reprotect registers */
 543         outb_p(VGA_CRTC_V_SYNC_END, vga_video_port_reg);
 544         outb_p(vsync_end, vga_video_port_val);
 545
 546         spin_unlock_irqrestore(&vga_lock, flags);
 547
 548         return 0;
 549 }
 550
 551 static int vgacon_switch(struct vc_data *c)
 552 {
 553         /*
 554          * We need to save screen size here as it's the only way
 555          * we can spot the screen has been resized and we need to
 556          * set size of freshly allocated screens ourselves.
 557          */
 558         vga_video_num_columns = c->vc_cols;
 559         vga_video_num_lines = c->vc_rows;
 560
 561         /* We can only copy out the size of the video buffer here,
 562          * otherwise we get into VGA BIOS */
 563
 564         if (!vga_is_gfx) {
 565                 scr_memcpyw((u16 *) c->vc_origin, (u16 *) c->vc_screenbuf,
 566                             c->vc_screenbuf_size > vga_vram_size ?
 567                                 vga_vram_size : c->vc_screenbuf_size);
 568                 if (!(vga_video_num_columns % 2) &&
 569                     vga_video_num_columns <= ORIG_VIDEO_COLS &&
 570                     vga_video_num_lines <= (ORIG_VIDEO_LINES *
 571                         vga_default_font_height) / c->vc_font.height)
 572                         vgacon_doresize(c, c->vc_cols, c->vc_rows);
 573         }
 574
 575         return 0;               /* Redrawing not needed */
 576 }
 577
 578 static void vga_set_palette(struct vc_data *vc, unsigned char *table)
 579 {
 580         int i, j;
 581
 582         for (i = j = 0; i < 16; i++) {
 583                 vga_w(state.vgabase, VGA_PEL_IW, table[i]);
 584                 vga_w(state.vgabase, VGA_PEL_D, vc->vc_palette[j++] >> 2);
 585                 vga_w(state.vgabase, VGA_PEL_D, vc->vc_palette[j++] >> 2);
 586                 vga_w(state.vgabase, VGA_PEL_D, vc->vc_palette[j++] >> 2);
 587         }
 588 }
 589
 590 static int vgacon_set_palette(struct vc_data *vc, unsigned char *table)
 591 {
 592 #ifdef CAN_LOAD_PALETTE
 593         if (vga_video_type != VIDEO_TYPE_VGAC || vga_palette_blanked
 594             || !CON_IS_VISIBLE(vc))
 595                 return -EINVAL;
 596         vga_set_palette(vc, table);
 597         return 0;
 598 #else
 599         return -EINVAL;
 600 #endif
 601 }
 602
 603 /* structure holding original VGA register settings */
 604 static struct {
 605         unsigned char SeqCtrlIndex;     /* Sequencer Index reg.   */
 606         unsigned char CrtCtrlIndex;     /* CRT-Contr. Index reg.  */
 607         unsigned char CrtMiscIO;        /* Miscellaneous register */
 608         unsigned char HorizontalTotal;  /* CRT-Controller:00h */
 609         unsigned char HorizDisplayEnd;  /* CRT-Controller:01h */
 610         unsigned char StartHorizRetrace;        /* CRT-Controller:04h */
 611         unsigned char EndHorizRetrace;  /* CRT-Controller:05h */
 612         unsigned char Overflow; /* CRT-Controller:07h */
 613         unsigned char StartVertRetrace; /* CRT-Controller:10h */
 614         unsigned char EndVertRetrace;   /* CRT-Controller:11h */
 615         unsigned char ModeControl;      /* CRT-Controller:17h */
 616         unsigned char ClockingMode;     /* Seq-Controller:01h */
 617 } vga_state;
 618
 619 static void vga_vesa_blank(struct vgastate *state, int mode)
 620 {
 621         /* save original values of VGA controller registers */
 622         if (!vga_vesa_blanked) {
 623                 spin_lock_irq(&vga_lock);
 624                 vga_state.SeqCtrlIndex = vga_r(state->vgabase, VGA_SEQ_I);
 625                 vga_state.CrtCtrlIndex = inb_p(vga_video_port_reg);
 626                 vga_state.CrtMiscIO = vga_r(state->vgabase, VGA_MIS_R);
 627                 spin_unlock_irq(&vga_lock);
 628
 629                 outb_p(0x00, vga_video_port_reg);       /* HorizontalTotal */
 630                 vga_state.HorizontalTotal = inb_p(vga_video_port_val);
 631                 outb_p(0x01, vga_video_port_reg);       /* HorizDisplayEnd */
 632                 vga_state.HorizDisplayEnd = inb_p(vga_video_port_val);
 633                 outb_p(0x04, vga_video_port_reg);       /* StartHorizRetrace */
 634                 vga_state.StartHorizRetrace = inb_p(vga_video_port_val);
 635                 outb_p(0x05, vga_video_port_reg);       /* EndHorizRetrace */
 636                 vga_state.EndHorizRetrace = inb_p(vga_video_port_val);
 637                 outb_p(0x07, vga_video_port_reg);       /* Overflow */
 638                 vga_state.Overflow = inb_p(vga_video_port_val);
 639                 outb_p(0x10, vga_video_port_reg);       /* StartVertRetrace */
 640                 vga_state.StartVertRetrace = inb_p(vga_video_port_val);
 641                 outb_p(0x11, vga_video_port_reg);       /* EndVertRetrace */
 642                 vga_state.EndVertRetrace = inb_p(vga_video_port_val);
 643                 outb_p(0x17, vga_video_port_reg);       /* ModeControl */
 644                 vga_state.ModeControl = inb_p(vga_video_port_val);
 645                 vga_state.ClockingMode = vga_rseq(state->vgabase, VGA_SEQ_CLOCK_MODE);
 646         }
 647
 648         /* assure that video is enabled */
 649         /* "0x20" is VIDEO_ENABLE_bit in register 01 of sequencer */
 650         spin_lock_irq(&vga_lock);
 651         vga_wseq(state->vgabase, VGA_SEQ_CLOCK_MODE, vga_state.ClockingMode | 0x20);
 652
 653         /* test for vertical retrace in process.... */
 654         if ((vga_state.CrtMiscIO & 0x80) == 0x80)
 655                 vga_w(state->vgabase, VGA_MIS_W, vga_state.CrtMiscIO & 0xEF);
 656
 657         /*
 658          * Set <End of vertical retrace> to minimum (0) and
 659          * <Start of vertical Retrace> to maximum (incl. overflow)
 660          * Result: turn off vertical sync (VSync) pulse.
 661          */
 662         if (mode & VESA_VSYNC_SUSPEND) {
 663                 outb_p(0x10, vga_video_port_reg);       /* StartVertRetrace */
 664                 outb_p(0xff, vga_video_port_val);       /* maximum value */
 665                 outb_p(0x11, vga_video_port_reg);       /* EndVertRetrace */
 666                 outb_p(0x40, vga_video_port_val);       /* minimum (bits 0..3)  */
 667                 outb_p(0x07, vga_video_port_reg);       /* Overflow */
 668                 outb_p(vga_state.Overflow | 0x84, vga_video_port_val);  /* bits 9,10 of vert. retrace */
 669         }
 670
 671         if (mode & VESA_HSYNC_SUSPEND) {
 672                 /*
 673                  * Set <End of horizontal retrace> to minimum (0) and
 674                  *  <Start of horizontal Retrace> to maximum
 675                  * Result: turn off horizontal sync (HSync) pulse.
 676                  */
 677                 outb_p(0x04, vga_video_port_reg);       /* StartHorizRetrace */
 678                 outb_p(0xff, vga_video_port_val);       /* maximum */
 679                 outb_p(0x05, vga_video_port_reg);       /* EndHorizRetrace */
 680                 outb_p(0x00, vga_video_port_val);       /* minimum (0) */
 681         }
 682
 683         /* restore both index registers */
 684         vga_w(state->vgabase, VGA_SEQ_I, vga_state.SeqCtrlIndex);
 685         outb_p(vga_state.CrtCtrlIndex, vga_video_port_reg);
 686         spin_unlock_irq(&vga_lock);
 687 }
 688
 689 static void vga_vesa_unblank(struct vgastate *state)
 690 {
 691         /* restore original values of VGA controller registers */
 692         spin_lock_irq(&vga_lock);
 693         vga_w(state->vgabase, VGA_MIS_W, vga_state.CrtMiscIO);
 694
 695         outb_p(0x00, vga_video_port_reg);       /* HorizontalTotal */
 696         outb_p(vga_state.HorizontalTotal, vga_video_port_val);
 697         outb_p(0x01, vga_video_port_reg);       /* HorizDisplayEnd */
 698         outb_p(vga_state.HorizDisplayEnd, vga_video_port_val);
 699         outb_p(0x04, vga_video_port_reg);       /* StartHorizRetrace */
 700         outb_p(vga_state.StartHorizRetrace, vga_video_port_val);
 701         outb_p(0x05, vga_video_port_reg);       /* EndHorizRetrace */
 702         outb_p(vga_state.EndHorizRetrace, vga_video_port_val);
 703         outb_p(0x07, vga_video_port_reg);       /* Overflow */
 704         outb_p(vga_state.Overflow, vga_video_port_val);
 705         outb_p(0x10, vga_video_port_reg);       /* StartVertRetrace */
 706         outb_p(vga_state.StartVertRetrace, vga_video_port_val);
 707         outb_p(0x11, vga_video_port_reg);       /* EndVertRetrace */
 708         outb_p(vga_state.EndVertRetrace, vga_video_port_val);
 709         outb_p(0x17, vga_video_port_reg);       /* ModeControl */
 710         outb_p(vga_state.ModeControl, vga_video_port_val);
 711         /* ClockingMode */
 712         vga_wseq(state->vgabase, VGA_SEQ_CLOCK_MODE, vga_state.ClockingMode);
 713
 714         /* restore index/control registers */
 715         vga_w(state->vgabase, VGA_SEQ_I, vga_state.SeqCtrlIndex);
 716         outb_p(vga_state.CrtCtrlIndex, vga_video_port_reg);
 717         spin_unlock_irq(&vga_lock);
 718 }
 719
 720 static void vga_pal_blank(struct vgastate *state)
 721 {
 722         int i;
 723
 724         for (i = 0; i < 16; i++) {
 725                 vga_w(state->vgabase, VGA_PEL_IW, i);
 726                 vga_w(state->vgabase, VGA_PEL_D, 0);
 727                 vga_w(state->vgabase, VGA_PEL_D, 0);
 728                 vga_w(state->vgabase, VGA_PEL_D, 0);
 729         }
 730 }
 731
 732 static int vgacon_blank(struct vc_data *c, int blank, int mode_switch)
 733 {
 734         switch (blank) {
 735         case 0:         /* Unblank */
 736                 if (vga_vesa_blanked) {
 737                         vga_vesa_unblank(&state);
 738                         vga_vesa_blanked = 0;
 739                 }
 740                 if (vga_palette_blanked) {
 741                         vga_set_palette(c, color_table);
 742                         vga_palette_blanked = 0;
 743                         return 0;
 744                 }
 745                 vga_is_gfx = 0;
 746                 /* Tell console.c that it has to restore the screen itself */
 747                 return 1;
 748         case 1:         /* Normal blanking */
 749         case -1:        /* Obsolete */
 750                 if (!mode_switch && vga_video_type == VIDEO_TYPE_VGAC) {
 751                         vga_pal_blank(&state);
 752                         vga_palette_blanked = 1;
 753                         return 0;
 754                 }
 755                 vgacon_set_origin(c);
 756                 scr_memsetw((void *) vga_vram_base, BLANK,
 757                             c->vc_screenbuf_size);
 758                 if (mode_switch)
 759                         vga_is_gfx = 1;
 760                 return 1;
 761         default:                /* VESA blanking */
 762                 if (vga_video_type == VIDEO_TYPE_VGAC) {
 763                         vga_vesa_blank(&state, blank - 1);
 764                         vga_vesa_blanked = blank;
 765                 }
 766                 return 0;
 767         }
 768 }
 769
 770 /*
 771  * PIO_FONT support.
 772  *
 773  * The font loading code goes back to the codepage package by
 774  * Joel Hoffman (joel@wam.umd.edu). (He reports that the original
 775  * reference is: "From: p. 307 of _Programmer's Guide to PC & PS/2
 776  * Video Systems_ by Richard Wilton. 1987.  Microsoft Press".)
 777  *
 778  * Change for certain monochrome monitors by Yury Shevchuck
 779  * (sizif@botik.yaroslavl.su).
 780  */
 781
 782 #ifdef CAN_LOAD_EGA_FONTS
 783
 784 #define colourmap 0xa0000
 785 /* Pauline Middelink <middelin@polyware.iaf.nl> reports that we
 786    should use 0xA0000 for the bwmap as well.. */
 787 #define blackwmap 0xa0000
 788 #define cmapsz 8192
 789
 790 static int vgacon_do_font_op(struct vgastate *state,char *arg,int set,int ch512)
 791 {
 792         unsigned short video_port_status = vga_video_port_reg + 6;
 793         int font_select = 0x00, beg, i;
 794         char *charmap;
 795
 796         if (vga_video_type != VIDEO_TYPE_EGAM) {
 797                 charmap = (char *) VGA_MAP_MEM(colourmap);
 798                 beg = 0x0e;
 799 #ifdef VGA_CAN_DO_64KB
 800                 if (vga_video_type == VIDEO_TYPE_VGAC)
 801                         beg = 0x06;
 802 #endif
 803         } else {
 804                 charmap = (char *) VGA_MAP_MEM(blackwmap);
 805                 beg = 0x0a;
 806         }
 807
 808 #ifdef BROKEN_GRAPHICS_PROGRAMS
 809         /*
 810          * All fonts are loaded in slot 0 (0:1 for 512 ch)
 811          */
 812
 813         if (!arg)
 814                 return -EINVAL; /* Return to default font not supported */
 815
 816         vga_font_is_default = 0;
 817         font_select = ch512 ? 0x04 : 0x00;
 818 #else
 819         /*
 820          * The default font is kept in slot 0 and is never touched.
 821          * A custom font is loaded in slot 2 (256 ch) or 2:3 (512 ch)
 822          */
 823
 824         if (set) {
 825                 vga_font_is_default = !arg;
 826                 if (!arg)
 827                         ch512 = 0;      /* Default font is always 256 */
 828                 font_select = arg ? (ch512 ? 0x0e : 0x0a) : 0x00;
 829         }
 830
 831         if (!vga_font_is_default)
 832                 charmap += 4 * cmapsz;
 833 #endif
 834
 835         unlock_kernel();
 836         spin_lock_irq(&vga_lock);
 837         /* First, the Sequencer */
 838         vga_wseq(state->vgabase, VGA_SEQ_RESET, 0x1);
 839         /* CPU writes only to map 2 */
 840         vga_wseq(state->vgabase, VGA_SEQ_PLANE_WRITE, 0x04);
 841         /* Sequential addressing */
 842         vga_wseq(state->vgabase, VGA_SEQ_MEMORY_MODE, 0x07);
 843         /* Clear synchronous reset */
 844         vga_wseq(state->vgabase, VGA_SEQ_RESET, 0x03);
 845
 846         /* Now, the graphics controller, select map 2 */
 847         vga_wgfx(state->vgabase, VGA_GFX_PLANE_READ, 0x02);
 848         /* disable odd-even addressing */
 849         vga_wgfx(state->vgabase, VGA_GFX_MODE, 0x00);
 850         /* map start at A000:0000 */
 851         vga_wgfx(state->vgabase, VGA_GFX_MISC, 0x00);
 852         spin_unlock_irq(&vga_lock);
 853
 854         if (arg) {
 855                 if (set)
 856                         for (i = 0; i < cmapsz; i++)
 857                                 vga_writeb(arg[i], charmap + i);
 858                 else
 859                         for (i = 0; i < cmapsz; i++)
 860                                 arg[i] = vga_readb(charmap + i);
 861
 862                 /*
 863                  * In 512-character mode, the character map is not contiguous if
 864                  * we want to remain EGA compatible -- which we do
 865                  */
 866
 867                 if (ch512) {
 868                         charmap += 2 * cmapsz;
 869                         arg += cmapsz;
 870                         if (set)
 871                                 for (i = 0; i < cmapsz; i++)
 872                                         vga_writeb(arg[i], charmap + i);
 873                         else
 874                                 for (i = 0; i < cmapsz; i++)
 875                                         arg[i] = vga_readb(charmap + i);
 876                 }
 877         }
 878
 879         spin_lock_irq(&vga_lock);
 880         /* First, the sequencer, Synchronous reset */
 881         vga_wseq(state->vgabase, VGA_SEQ_RESET, 0x01);
 882         /* CPU writes to maps 0 and 1 */
 883         vga_wseq(state->vgabase, VGA_SEQ_PLANE_WRITE, 0x03);
 884         /* odd-even addressing */
 885         vga_wseq(state->vgabase, VGA_SEQ_MEMORY_MODE, 0x03);
 886         /* Character Map Select */
 887         if (set)
 888                 vga_wseq(state->vgabase, VGA_SEQ_CHARACTER_MAP, font_select);
 889         /* clear synchronous reset */
 890         vga_wseq(state->vgabase, VGA_SEQ_RESET, 0x03);
 891
 892         /* Now, the graphics controller, select map 0 for CPU */
 893         vga_wgfx(state->vgabase, VGA_GFX_PLANE_READ, 0x00);
 894         /* enable even-odd addressing */
 895         vga_wgfx(state->vgabase, VGA_GFX_MODE, 0x10);
 896         /* map starts at b800:0 or b000:0 */
 897         vga_wgfx(state->vgabase, VGA_GFX_MISC, beg);
 898
 899         /* if 512 char mode is already enabled don't re-enable it. */
 900         if ((set) && (ch512 != vga_512_chars)) {
 901                 int i;
 902
 903                 /* attribute controller */
 904                 for (i = 0; i < MAX_NR_CONSOLES; i++) {
 905                         struct vc_data *c = vc_cons[i].d;
 906                         if (c && c->vc_sw == &vga_con)
 907                                 c->vc_hi_font_mask = ch512 ? 0x0800 : 0;
 908                 }
 909                 vga_512_chars = ch512;
 910                 /* 256-char: enable intensity bit
 911                    512-char: disable intensity bit */
 912                 inb_p(video_port_status);       /* clear address flip-flop */
 913                 /* color plane enable register */
 914                 vga_wattr(state->vgabase, VGA_ATC_PLANE_ENABLE, ch512 ? 0x07 : 0x0f);
 915                 /* Wilton (1987) mentions the following; I don't know what
 916                    it means, but it works, and it appears necessary */
 917                 inb_p(video_port_status);
 918                 vga_wattr(state->vgabase, VGA_AR_ENABLE_DISPLAY, 0);
 919         }
 920         spin_unlock_irq(&vga_lock);
 921         lock_kernel();
 922         return 0;
 923 }
 924
 925 /*
 926  * Adjust the screen to fit a font of a certain height
 927  */
 928 static int vgacon_adjust_height(struct vc_data *vc, unsigned fontheight)
 929 {
 930         unsigned char ovr, vde, fsr;
 931         int rows, maxscan, i;
 932
 933         rows = vc->vc_scan_lines / fontheight;  /* Number of video rows we end up with */
 934         maxscan = rows * fontheight - 1;        /* Scan lines to actually display-1 */
 935
 936         /* Reprogram the CRTC for the new font size
 937            Note: the attempt to read the overflow register will fail
 938            on an EGA, but using 0xff for the previous value appears to
 939            be OK for EGA text modes in the range 257-512 scan lines, so I
 940            guess we don't need to worry about it.
 941
 942            The same applies for the spill bits in the font size and cursor
 943            registers; they are write-only on EGA, but it appears that they
 944            are all don't care bits on EGA, so I guess it doesn't matter. */
 945
 946         spin_lock_irq(&vga_lock);
 947         outb_p(0x07, vga_video_port_reg);       /* CRTC overflow register */
 948         ovr = inb_p(vga_video_port_val);
 949         outb_p(0x09, vga_video_port_reg);       /* Font size register */
 950         fsr = inb_p(vga_video_port_val);
 951         spin_unlock_irq(&vga_lock);
 952
 953         vde = maxscan & 0xff;   /* Vertical display end reg */
 954         ovr = (ovr & 0xbd) +    /* Overflow register */
 955             ((maxscan & 0x100) >> 7) + ((maxscan & 0x200) >> 3);
 956         fsr = (fsr & 0xe0) + (fontheight - 1);  /*  Font size register */
 957
 958         spin_lock_irq(&vga_lock);
 959         outb_p(0x07, vga_video_port_reg);       /* CRTC overflow register */
 960         outb_p(ovr, vga_video_port_val);
 961         outb_p(0x09, vga_video_port_reg);       /* Font size */
 962         outb_p(fsr, vga_video_port_val);
 963         outb_p(0x12, vga_video_port_reg);       /* Vertical display limit */
 964         outb_p(vde, vga_video_port_val);
 965         spin_unlock_irq(&vga_lock);
 966
 967         for (i = 0; i < MAX_NR_CONSOLES; i++) {
 968                 struct vc_data *c = vc_cons[i].d;
 969
 970                 if (c && c->vc_sw == &vga_con) {
 971                         if (CON_IS_VISIBLE(c)) {
 972                                 /* void size to cause regs to be rewritten */
 973                                 cursor_size_lastfrom = 0;
 974                                 cursor_size_lastto = 0;
 975                                 c->vc_sw->con_cursor(c, CM_DRAW);
 976                         }
 977                         c->vc_font.height = fontheight;
 978                         vc_resize(c, 0, rows);  /* Adjust console size */
 979                 }
 980         }
 981         return 0;
 982 }
 983
 984 static int vgacon_font_set(struct vc_data *c, struct console_font *font, unsigned flags)
 985 {
 986         unsigned charcount = font->charcount;
 987         int rc;
 988
 989         if (vga_video_type < VIDEO_TYPE_EGAM)
 990                 return -EINVAL;
 991
 992         if (font->width != 8 || (charcount != 256 && charcount != 512))
 993                 return -EINVAL;
 994
 995         rc = vgacon_do_font_op(&state, font->data, 1, charcount == 512);
 996         if (rc)
 997                 return rc;
 998
 999         if (!(flags & KD_FONT_FLAG_DONT_RECALC))
1000                 rc = vgacon_adjust_height(c, font->height);
1001         return rc;
1002 }
1003
1004 static int vgacon_font_get(struct vc_data *c, struct console_font *font)
1005 {
1006         if (vga_video_type < VIDEO_TYPE_EGAM)
1007                 return -EINVAL;
1008
1009         font->width = 8;
1010         font->height = c->vc_font.height;
1011         font->charcount = vga_512_chars ? 512 : 256;
1012         if (!font->data)
1013                 return 0;
1014         return vgacon_do_font_op(&state, font->data, 0, 0);
1015 }
1016
1017 #else
1018
1019 #define vgacon_font_set NULL
1020 #define vgacon_font_get NULL
1021
1022 #endif
1023
1024 static int vgacon_resize(struct vc_data *c, unsigned int width,
1025                                 unsigned int height)
1026 {
1027         if (width % 2 || width > ORIG_VIDEO_COLS ||
1028             height > (ORIG_VIDEO_LINES * vga_default_font_height)/
1029             c->vc_font.height)
1030                 /* let svgatextmode tinker with video timings */
1031                 return 0;
1032
1033         if (CON_IS_VISIBLE(c) && !vga_is_gfx) /* who knows */
1034                 vgacon_doresize(c, width, height);
1035         return 0;
1036 }
1037
1038 static int vgacon_scrolldelta(struct vc_data *c, int lines)
1039 {
1040         if (!lines)             /* Turn scrollback off */
1041                 c->vc_visible_origin = c->vc_origin;
1042         else {
1043                 int margin = c->vc_size_row * 4;
1044                 int ul, we, p, st;
1045
1046                 if (vga_rolled_over >
1047                     (c->vc_scr_end - vga_vram_base) + margin) {
1048                         ul = c->vc_scr_end - vga_vram_base;
1049                         we = vga_rolled_over + c->vc_size_row;
1050                 } else {
1051                         ul = 0;
1052                         we = vga_vram_size;
1053                 }
1054                 p = (c->vc_visible_origin - vga_vram_base - ul + we) % we +
1055                     lines * c->vc_size_row;
1056                 st = (c->vc_origin - vga_vram_base - ul + we) % we;
1057                 if (st < 2 * margin)
1058                         margin = 0;
1059                 if (p < margin)
1060                         p = 0;
1061                 if (p > st - margin)
1062                         p = st;
1063                 c->vc_visible_origin = vga_vram_base + (p + ul) % we;
1064         }
1065         vga_set_mem_top(c);
1066         return 1;
1067 }
1068
1069 static int vgacon_set_origin(struct vc_data *c)
1070 {
1071         if (vga_is_gfx ||       /* We don't play origin tricks in graphic modes */
1072             (console_blanked && !vga_palette_blanked))  /* Nor we write to blanked screens */
1073                 return 0;
1074         c->vc_origin = c->vc_visible_origin = vga_vram_base;
1075         vga_set_mem_top(c);
1076         vga_rolled_over = 0;
1077         return 1;
1078 }
1079
1080 static void vgacon_save_screen(struct vc_data *c)
1081 {
1082         static int vga_bootup_console = 0;
1083
1084         if (!vga_bootup_console) {
1085                 /* This is a gross hack, but here is the only place we can
1086                  * set bootup console parameters without messing up generic
1087                  * console initialization routines.
1088                  */
1089                 vga_bootup_console = 1;
1090                 c->vc_x = ORIG_X;
1091                 c->vc_y = ORIG_Y;
1092         }
1093
1094         /* We can't copy in more then the size of the video buffer,
1095          * or we'll be copying in VGA BIOS */
1096
1097         if (!vga_is_gfx)
1098                 scr_memcpyw((u16 *) c->vc_screenbuf, (u16 *) c->vc_origin,
1099                             c->vc_screenbuf_size > vga_vram_size ? vga_vram_size : c->vc_screenbuf_size);
1100 }
1101
1102 static int vgacon_scroll(struct vc_data *c, int t, int b, int dir,
1103                          int lines)
1104 {
1105         unsigned long oldo;
1106         unsigned int delta;
1107
1108         if (t || b != c->vc_rows || vga_is_gfx)
1109                 return 0;
1110
1111         if (c->vc_origin != c->vc_visible_origin)
1112                 vgacon_scrolldelta(c, 0);
1113
1114         if (!vga_hardscroll_enabled || lines >= c->vc_rows / 2)
1115                 return 0;
1116
1117         oldo = c->vc_origin;
1118         delta = lines * c->vc_size_row;
1119         if (dir == SM_UP) {
1120                 if (c->vc_scr_end + delta >= vga_vram_end) {
1121                         scr_memcpyw((u16 *) vga_vram_base,
1122                                     (u16 *) (oldo + delta),
1123                                     c->vc_screenbuf_size - delta);
1124                         c->vc_origin = vga_vram_base;
1125                         vga_rolled_over = oldo - vga_vram_base;
1126                 } else
1127                         c->vc_origin += delta;
1128                 scr_memsetw((u16 *) (c->vc_origin + c->vc_screenbuf_size -
1129                                      delta), c->vc_video_erase_char,
1130                             delta);
1131         } else {
1132                 if (oldo - delta < vga_vram_base) {
1133                         scr_memmovew((u16 *) (vga_vram_end -
1134                                               c->vc_screenbuf_size +
1135                                               delta), (u16 *) oldo,
1136                                      c->vc_screenbuf_size - delta);
1137                         c->vc_origin = vga_vram_end - c->vc_screenbuf_size;
1138                         vga_rolled_over = 0;
1139                 } else
1140                         c->vc_origin -= delta;
1141                 c->vc_scr_end = c->vc_origin + c->vc_screenbuf_size;
1142                 scr_memsetw((u16 *) (c->vc_origin), c->vc_video_erase_char,
1143                             delta);
1144         }
1145         c->vc_scr_end = c->vc_origin + c->vc_screenbuf_size;
1146         c->vc_visible_origin = c->vc_origin;
1147         vga_set_mem_top(c);
1148         c->vc_pos = (c->vc_pos - oldo) + c->vc_origin;
1149         return 1;
1150 }
1151
1152
1153 /*
1154  *  The console `switch' structure for the VGA based console
1155  */
1156
1157 static int vgacon_dummy(struct vc_data *c)
1158 {
1159         return 0;
1160 }
1161
1162 #define DUMMY (void *) vgacon_dummy
1163
1164 const struct consw vga_con = {
1165         .owner = THIS_MODULE,
1166         .con_startup = vgacon_startup,
1167         .con_init = vgacon_init,
1168         .con_deinit = vgacon_deinit,
1169         .con_clear = DUMMY,
1170         .con_putc = DUMMY,
1171         .con_putcs = DUMMY,
1172         .con_cursor = vgacon_cursor,
1173         .con_scroll = vgacon_scroll,
1174         .con_bmove = DUMMY,
1175         .con_switch = vgacon_switch,
1176         .con_blank = vgacon_blank,
1177         .con_font_set = vgacon_font_set,
1178         .con_font_get = vgacon_font_get,
1179         .con_resize = vgacon_resize,
1180         .con_set_palette = vgacon_set_palette,
1181         .con_scrolldelta = vgacon_scrolldelta,
1182         .con_set_origin = vgacon_set_origin,
1183         .con_save_screen = vgacon_save_screen,
1184         .con_build_attr = vgacon_build_attr,
1185         .con_invert_region = vgacon_invert_region,
1186 };
1187
1188 MODULE_LICENSE("GPL");