drivers/video/vgastate.c

   1 /*
   2  * linux/drivers/video/vgastate.c -- VGA state save/restore
   3  *
   4  * Copyright 2002 James Simmons
   5  *
   6  * Copyright history from vga16fb.c:
   7  *      Copyright 1999 Ben Pfaff and Petr Vandrovec
   8  *      Based on VGA info at http://www.goodnet.com/~tinara/FreeVGA/home.htm
   9  *      Based on VESA framebuffer (c) 1998 Gerd Knorr
  10  *
  11  * This file is subject to the terms and conditions of the GNU General
  12  * Public License.  See the file COPYING in the main directory of this
  13  * archive for more details.
  14  *
  15  */
  16 #include <linux/module.h>
  17 #include <linux/slab.h>
  18 #include <linux/fb.h>
  19 #include <linux/vmalloc.h>
  20 #include <video/vga.h>
  21
  22 struct regstate {
  23         __u8 *vga_font0;
  24         __u8 *vga_font1;
  25         __u8 *vga_text;
  26         __u8 *vga_cmap;
  27         __u8 *attr;
  28         __u8 *crtc;
  29         __u8 *gfx;
  30         __u8 *seq;
  31         __u8 misc;
  32 };
  33
  34 static inline unsigned char vga_rcrtcs(void __iomem *regbase, unsigned short iobase,
  35                                        unsigned char reg)
  36 {
  37         vga_w(regbase, iobase + 0x4, reg);
  38         return vga_r(regbase, iobase + 0x5);
  39 }
  40
  41 static inline void vga_wcrtcs(void __iomem *regbase, unsigned short iobase,
  42                               unsigned char reg, unsigned char val)
  43 {
  44         vga_w(regbase, iobase + 0x4, reg);
  45         vga_w(regbase, iobase + 0x5, val);
  46 }
  47
  48 static void save_vga_text(struct vgastate *state, void __iomem *fbbase)
  49 {
  50         struct regstate *saved = (struct regstate *) state->vidstate;
  51         int i;
  52         u8 misc, attr10, gr4, gr5, gr6, seq1, seq2, seq4;
  53
  54         /* if in graphics mode, no need to save */
  55         attr10 = vga_rattr(state->vgabase, 0x10);
  56         if (attr10 & 1)
  57                 return;
  58
  59         /* save regs */
  60         misc = vga_r(state->vgabase, VGA_MIS_R);
  61         gr4 = vga_rgfx(state->vgabase, VGA_GFX_PLANE_READ);
  62         gr5 = vga_rgfx(state->vgabase, VGA_GFX_MODE);
  63         gr6 = vga_rgfx(state->vgabase, VGA_GFX_MISC);
  64         seq2 = vga_rseq(state->vgabase, VGA_SEQ_PLANE_WRITE);
  65         seq4 = vga_rseq(state->vgabase, VGA_SEQ_MEMORY_MODE);
  66
  67         /* force graphics mode */
  68         vga_w(state->vgabase, VGA_MIS_W, misc | 1);
  69
  70         /* blank screen */
  71         seq1 = vga_rseq(state->vgabase, VGA_SEQ_CLOCK_MODE);
  72         vga_wseq(state->vgabase, VGA_SEQ_RESET, 0x1);
  73         vga_wseq(state->vgabase, VGA_SEQ_CLOCK_MODE, seq1 | 1 << 5);
  74         vga_wseq(state->vgabase, VGA_SEQ_RESET, 0x3);
  75
  76         /* save font at plane 2 */
  77         if (state->flags & VGA_SAVE_FONT0) {
  78                 vga_wseq(state->vgabase, VGA_SEQ_PLANE_WRITE, 0x4);
  79                 vga_wseq(state->vgabase, VGA_SEQ_MEMORY_MODE, 0x6);
  80                 vga_wgfx(state->vgabase, VGA_GFX_PLANE_READ, 0x2);
  81                 vga_wgfx(state->vgabase, VGA_GFX_MODE, 0x0);
  82                 vga_wgfx(state->vgabase, VGA_GFX_MISC, 0x5);
  83                 for (i = 0; i < 4 * 8192; i++)
  84                         saved->vga_font0[i] = vga_r(fbbase, i);
  85         }
  86
  87         /* save font at plane 3 */
  88         if (state->flags & VGA_SAVE_FONT1) {
  89                 vga_wseq(state->vgabase, VGA_SEQ_PLANE_WRITE, 0x8);
  90                 vga_wseq(state->vgabase, VGA_SEQ_MEMORY_MODE, 0x6);
  91                 vga_wgfx(state->vgabase, VGA_GFX_PLANE_READ, 0x3);
  92                 vga_wgfx(state->vgabase, VGA_GFX_MODE, 0x0);
  93                 vga_wgfx(state->vgabase, VGA_GFX_MISC, 0x5);
  94                 for (i = 0; i < state->memsize; i++)
  95                         saved->vga_font1[i] = vga_r(fbbase, i);
  96         }
  97
  98         /* save font at plane 0/1 */
  99         if (state->flags & VGA_SAVE_TEXT) {
 100                 vga_wseq(state->vgabase, VGA_SEQ_PLANE_WRITE, 0x1);
 101                 vga_wseq(state->vgabase, VGA_SEQ_MEMORY_MODE, 0x6);
 102                 vga_wgfx(state->vgabase, VGA_GFX_PLANE_READ, 0x0);
 103                 vga_wgfx(state->vgabase, VGA_GFX_MODE, 0x0);
 104                 vga_wgfx(state->vgabase, VGA_GFX_MISC, 0x5);
 105                 for (i = 0; i < 8192; i++)
 106                         saved->vga_text[i] = vga_r(fbbase, i);
 107
 108                 vga_wseq(state->vgabase, VGA_SEQ_PLANE_WRITE, 0x2);
 109                 vga_wseq(state->vgabase, VGA_SEQ_MEMORY_MODE, 0x6);
 110                 vga_wgfx(state->vgabase, VGA_GFX_PLANE_READ, 0x1);
 111                 vga_wgfx(state->vgabase, VGA_GFX_MODE, 0x0);
 112                 vga_wgfx(state->vgabase, VGA_GFX_MISC, 0x5);
 113                 for (i = 0; i < 8192; i++)
 114                         saved->vga_text[8192+i] = vga_r(fbbase + 2 * 8192, i);
 115         }
 116
 117         /* restore regs */
 118         vga_wattr(state->vgabase, 0x10, attr10);
 119
 120         vga_wseq(state->vgabase, VGA_SEQ_PLANE_WRITE, seq2);
 121         vga_wseq(state->vgabase, VGA_SEQ_MEMORY_MODE, seq4);
 122
 123         vga_wgfx(state->vgabase, VGA_GFX_PLANE_READ, gr4);
 124         vga_wgfx(state->vgabase, VGA_GFX_MODE, gr5);
 125         vga_wgfx(state->vgabase, VGA_GFX_MISC, gr6);
 126         vga_w(state->vgabase, VGA_MIS_W, misc);
 127
 128         /* unblank screen */
 129         vga_wseq(state->vgabase, VGA_SEQ_RESET, 0x1);
 130         vga_wseq(state->vgabase, VGA_SEQ_CLOCK_MODE, seq1 & ~(1 << 5));
 131         vga_wseq(state->vgabase, VGA_SEQ_RESET, 0x3);
 132
 133         vga_wseq(state->vgabase, VGA_SEQ_CLOCK_MODE, seq1);
 134 }
 135
 136 static void restore_vga_text(struct vgastate *state, void __iomem *fbbase)
 137 {
 138         struct regstate *saved = (struct regstate *) state->vidstate;
 139         int i;
 140         u8 misc, gr1, gr3, gr4, gr5, gr6, gr8;
 141         u8 seq1, seq2, seq4;
 142
 143         /* save regs */
 144         misc = vga_r(state->vgabase, VGA_MIS_R);
 145         gr1 = vga_rgfx(state->vgabase, VGA_GFX_SR_ENABLE);
 146         gr3 = vga_rgfx(state->vgabase, VGA_GFX_DATA_ROTATE);
 147         gr4 = vga_rgfx(state->vgabase, VGA_GFX_PLANE_READ);
 148         gr5 = vga_rgfx(state->vgabase, VGA_GFX_MODE);
 149         gr6 = vga_rgfx(state->vgabase, VGA_GFX_MISC);
 150         gr8 = vga_rgfx(state->vgabase, VGA_GFX_BIT_MASK);
 151         seq2 = vga_rseq(state->vgabase, VGA_SEQ_PLANE_WRITE);
 152         seq4 = vga_rseq(state->vgabase, VGA_SEQ_MEMORY_MODE);
 153
 154         /* force graphics mode */
 155         vga_w(state->vgabase, VGA_MIS_W, misc | 1);
 156
 157         /* blank screen */
 158         seq1 = vga_rseq(state->vgabase, VGA_SEQ_CLOCK_MODE);
 159         vga_wseq(state->vgabase, VGA_SEQ_RESET, 0x1);
 160         vga_wseq(state->vgabase, VGA_SEQ_CLOCK_MODE, seq1 | 1 << 5);
 161         vga_wseq(state->vgabase, VGA_SEQ_RESET, 0x3);
 162
 163         if (state->depth == 4) {
 164                 vga_wgfx(state->vgabase, VGA_GFX_DATA_ROTATE, 0x0);
 165                 vga_wgfx(state->vgabase, VGA_GFX_BIT_MASK, 0xff);
 166                 vga_wgfx(state->vgabase, VGA_GFX_SR_ENABLE, 0x00);
 167         }
 168
 169         /* restore font at plane 2 */
 170         if (state->flags & VGA_SAVE_FONT0) {
 171                 vga_wseq(state->vgabase, VGA_SEQ_PLANE_WRITE, 0x4);
 172                 vga_wseq(state->vgabase, VGA_SEQ_MEMORY_MODE, 0x6);
 173                 vga_wgfx(state->vgabase, VGA_GFX_PLANE_READ, 0x2);
 174                 vga_wgfx(state->vgabase, VGA_GFX_MODE, 0x0);
 175                 vga_wgfx(state->vgabase, VGA_GFX_MISC, 0x5);
 176                 for (i = 0; i < 4 * 8192; i++)
 177                         vga_w(fbbase, i, saved->vga_font0[i]);
 178         }
 179
 180         /* restore font at plane 3 */
 181         if (state->flags & VGA_SAVE_FONT1) {
 182                 vga_wseq(state->vgabase, VGA_SEQ_PLANE_WRITE, 0x8);
 183                 vga_wseq(state->vgabase, VGA_SEQ_MEMORY_MODE, 0x6);
 184                 vga_wgfx(state->vgabase, VGA_GFX_PLANE_READ, 0x3);
 185                 vga_wgfx(state->vgabase, VGA_GFX_MODE, 0x0);
 186                 vga_wgfx(state->vgabase, VGA_GFX_MISC, 0x5);
 187                 for (i = 0; i < state->memsize; i++)
 188                         vga_w(fbbase, i, saved->vga_font1[i]);
 189         }
 190
 191         /* restore font at plane 0/1 */
 192         if (state->flags & VGA_SAVE_TEXT) {
 193                 vga_wseq(state->vgabase, VGA_SEQ_PLANE_WRITE, 0x1);
 194                 vga_wseq(state->vgabase, VGA_SEQ_MEMORY_MODE, 0x6);
 195                 vga_wgfx(state->vgabase, VGA_GFX_PLANE_READ, 0x0);
 196                 vga_wgfx(state->vgabase, VGA_GFX_MODE, 0x0);
 197                 vga_wgfx(state->vgabase, VGA_GFX_MISC, 0x5);
 198                 for (i = 0; i < 8192; i++)
 199                         vga_w(fbbase, i, saved->vga_text[i]);
 200
 201                 vga_wseq(state->vgabase, VGA_SEQ_PLANE_WRITE, 0x2);
 202                 vga_wseq(state->vgabase, VGA_SEQ_MEMORY_MODE, 0x6);
 203                 vga_wgfx(state->vgabase, VGA_GFX_PLANE_READ, 0x1);
 204                 vga_wgfx(state->vgabase, VGA_GFX_MODE, 0x0);
 205                 vga_wgfx(state->vgabase, VGA_GFX_MISC, 0x5);
 206                 for (i = 0; i < 8192; i++)
 207                         vga_w(fbbase, i, saved->vga_text[8192+i]);
 208         }
 209
 210         /* unblank screen */
 211         vga_wseq(state->vgabase, VGA_SEQ_RESET, 0x1);
 212         vga_wseq(state->vgabase, VGA_SEQ_CLOCK_MODE, seq1 & ~(1 << 5));
 213         vga_wseq(state->vgabase, VGA_SEQ_RESET, 0x3);
 214
 215         /* restore regs */
 216         vga_w(state->vgabase, VGA_MIS_W, misc);
 217
 218         vga_wgfx(state->vgabase, VGA_GFX_SR_ENABLE, gr1);
 219         vga_wgfx(state->vgabase, VGA_GFX_DATA_ROTATE, gr3);
 220         vga_wgfx(state->vgabase, VGA_GFX_PLANE_READ, gr4);
 221         vga_wgfx(state->vgabase, VGA_GFX_MODE, gr5);
 222         vga_wgfx(state->vgabase, VGA_GFX_MISC, gr6);
 223         vga_wgfx(state->vgabase, VGA_GFX_BIT_MASK, gr8);
 224
 225         vga_wseq(state->vgabase, VGA_SEQ_CLOCK_MODE, seq1);
 226         vga_wseq(state->vgabase, VGA_SEQ_PLANE_WRITE, seq2);
 227         vga_wseq(state->vgabase, VGA_SEQ_MEMORY_MODE, seq4);
 228 }
 229
 230 static void save_vga_mode(struct vgastate *state)
 231 {
 232         struct regstate *saved = (struct regstate *) state->vidstate;
 233         unsigned short iobase;
 234         int i;
 235
 236         saved->misc = vga_r(state->vgabase, VGA_MIS_R);
 237         if (saved->misc & 1)
 238                 iobase = 0x3d0;
 239         else
 240                 iobase = 0x3b0;
 241
 242         for (i = 0; i < state->num_crtc; i++)
 243                 saved->crtc[i] = vga_rcrtcs(state->vgabase, iobase, i);
 244
 245         vga_r(state->vgabase, iobase + 0xa);
 246         vga_w(state->vgabase, VGA_ATT_W, 0x00);
 247         for (i = 0; i < state->num_attr; i++) {
 248                 vga_r(state->vgabase, iobase + 0xa);
 249                 saved->attr[i] = vga_rattr(state->vgabase, i);
 250         }
 251         vga_r(state->vgabase, iobase + 0xa);
 252         vga_w(state->vgabase, VGA_ATT_W, 0x20);
 253
 254         for (i = 0; i < state->num_gfx; i++)
 255                 saved->gfx[i] = vga_rgfx(state->vgabase, i);
 256
 257         for (i = 0; i < state->num_seq; i++)
 258                 saved->seq[i] = vga_rseq(state->vgabase, i);
 259 }
 260
 261 static void restore_vga_mode(struct vgastate *state)
 262 {
 263         struct regstate *saved = (struct regstate *) state->vidstate;
 264         unsigned short iobase;
 265         int i;
 266
 267         vga_w(state->vgabase, VGA_MIS_W, saved->misc);
 268
 269         if (saved->misc & 1)
 270                 iobase = 0x3d0;
 271         else
 272                 iobase = 0x3b0;
 273
 274         /* turn off display */
 275         vga_wseq(state->vgabase, VGA_SEQ_CLOCK_MODE,
 276                  saved->seq[VGA_SEQ_CLOCK_MODE] | 0x20);
 277
 278         /* disable sequencer */
 279         vga_wseq(state->vgabase, VGA_SEQ_RESET, 0x01);
 280
 281         /* enable palette addressing */
 282         vga_r(state->vgabase, iobase + 0xa);
 283         vga_w(state->vgabase, VGA_ATT_W, 0x00);
 284
 285         for (i = 2; i < state->num_seq; i++)
 286                 vga_wseq(state->vgabase, i, saved->seq[i]);
 287
 288
 289         /* unprotect vga regs */
 290         vga_wcrtcs(state->vgabase, iobase, 17, saved->crtc[17] & ~0x80);
 291         for (i = 0; i < state->num_crtc; i++)
 292                 vga_wcrtcs(state->vgabase, iobase, i, saved->crtc[i]);
 293
 294         for (i = 0; i < state->num_gfx; i++)
 295                 vga_wgfx(state->vgabase, i, saved->gfx[i]);
 296
 297         for (i = 0; i < state->num_attr; i++) {
 298                 vga_r(state->vgabase, iobase + 0xa);
 299                 vga_wattr(state->vgabase, i, saved->attr[i]);
 300         }
 301
 302         /* reenable sequencer */
 303         vga_wseq(state->vgabase, VGA_SEQ_RESET, 0x03);
 304         /* turn display on */
 305         vga_wseq(state->vgabase, VGA_SEQ_CLOCK_MODE,
 306                  saved->seq[VGA_SEQ_CLOCK_MODE] & ~(1 << 5));
 307
 308         /* disable video/palette source */
 309         vga_r(state->vgabase, iobase + 0xa);
 310         vga_w(state->vgabase, VGA_ATT_W, 0x20);
 311 }
 312
 313 static void save_vga_cmap(struct vgastate *state)
 314 {
 315         struct regstate *saved = (struct regstate *) state->vidstate;
 316         int i;
 317
 318         vga_w(state->vgabase, VGA_PEL_MSK, 0xff);
 319
 320         /* assumes DAC is readable and writable */
 321         vga_w(state->vgabase, VGA_PEL_IR, 0x00);
 322         for (i = 0; i < 768; i++)
 323                 saved->vga_cmap[i] = vga_r(state->vgabase, VGA_PEL_D);
 324 }
 325
 326 static void restore_vga_cmap(struct vgastate *state)
 327 {
 328         struct regstate *saved = (struct regstate *) state->vidstate;
 329         int i;
 330
 331         vga_w(state->vgabase, VGA_PEL_MSK, 0xff);
 332
 333         /* assumes DAC is readable and writable */
 334         vga_w(state->vgabase, VGA_PEL_IW, 0x00);
 335         for (i = 0; i < 768; i++)
 336                 vga_w(state->vgabase, VGA_PEL_D, saved->vga_cmap[i]);
 337 }
 338
 339 static void vga_cleanup(struct vgastate *state)
 340 {
 341         if (state->vidstate != NULL) {
 342                 struct regstate *saved = (struct regstate *) state->vidstate;
 343
 344                 vfree(saved->vga_font0);
 345                 vfree(saved->vga_font1);
 346                 vfree(saved->vga_text);
 347                 vfree(saved->vga_cmap);
 348                 vfree(saved->attr);
 349                 kfree(saved);
 350                 state->vidstate = NULL;
 351         }
 352 }
 353
 354 int save_vga(struct vgastate *state)
 355 {
 356         struct regstate *saved;
 357
 358         saved = kzalloc(sizeof(struct regstate), GFP_KERNEL);
 359
 360         if (saved == NULL)
 361                 return 1;
 362
 363         state->vidstate = (void *)saved;
 364
 365         if (state->flags & VGA_SAVE_CMAP) {
 366                 saved->vga_cmap = vmalloc(768);
 367                 if (!saved->vga_cmap) {
 368                         vga_cleanup(state);
 369                         return 1;
 370                 }
 371                 save_vga_cmap(state);
 372         }
 373
 374         if (state->flags & VGA_SAVE_MODE) {
 375                 int total;
 376
 377                 if (state->num_attr < 21)
 378                         state->num_attr = 21;
 379                 if (state->num_crtc < 25)
 380                         state->num_crtc = 25;
 381                 if (state->num_gfx < 9)
 382                         state->num_gfx = 9;
 383                 if (state->num_seq < 5)
 384                         state->num_seq = 5;
 385                 total = state->num_attr + state->num_crtc +
 386                         state->num_gfx + state->num_seq;
 387
 388                 saved->attr = vmalloc(total);
 389                 if (!saved->attr) {
 390                         vga_cleanup(state);
 391                         return 1;
 392                 }
 393                 saved->crtc = saved->attr + state->num_attr;
 394                 saved->gfx = saved->crtc + state->num_crtc;
 395                 saved->seq = saved->gfx + state->num_gfx;
 396
 397                 save_vga_mode(state);
 398         }
 399
 400         if (state->flags & VGA_SAVE_FONTS) {
 401                 void __iomem *fbbase;
 402
 403                 /* exit if window is less than 32K */
 404                 if (state->memsize && state->memsize < 4 * 8192) {
 405                         vga_cleanup(state);
 406                         return 1;
 407                 }
 408                 if (!state->memsize)
 409                         state->memsize = 8 * 8192;
 410
 411                 if (!state->membase)
 412                         state->membase = 0xA0000;
 413
 414                 fbbase = ioremap(state->membase, state->memsize);
 415
 416                 if (!fbbase) {
 417                         vga_cleanup(state);
 418                         return 1;
 419                 }
 420
 421                 /*
 422                  * save only first 32K used by vgacon
 423                  */
 424                 if (state->flags & VGA_SAVE_FONT0) {
 425                         saved->vga_font0 = vmalloc(4 * 8192);
 426                         if (!saved->vga_font0) {
 427                                 iounmap(fbbase);
 428                                 vga_cleanup(state);
 429                                 return 1;
 430                         }
 431                 }
 432                 /*
 433                  * largely unused, but if required by the caller
 434                  * we'll just save everything.
 435                  */
 436                 if (state->flags & VGA_SAVE_FONT1) {
 437                         saved->vga_font1 = vmalloc(state->memsize);
 438                         if (!saved->vga_font1) {
 439                                 iounmap(fbbase);
 440                                 vga_cleanup(state);
 441                                 return 1;
 442                         }
 443                 }
 444                 /*
 445                  * Save 8K at plane0[0], and 8K at plane1[16K]
 446                  */
 447                 if (state->flags & VGA_SAVE_TEXT) {
 448                         saved->vga_text = vmalloc(8192 * 2);
 449                         if (!saved->vga_text) {
 450                                 iounmap(fbbase);
 451                                 vga_cleanup(state);
 452                                 return 1;
 453                         }
 454                 }
 455
 456                 save_vga_text(state, fbbase);
 457                 iounmap(fbbase);
 458         }
 459         return 0;
 460 }
 461
 462 int restore_vga (struct vgastate *state)
 463 {
 464         if (state->vidstate == NULL)
 465                 return 1;
 466
 467         if (state->flags & VGA_SAVE_MODE)
 468                 restore_vga_mode(state);
 469
 470         if (state->flags & VGA_SAVE_FONTS) {
 471                 void __iomem *fbbase = ioremap(state->membase, state->memsize);
 472
 473                 if (!fbbase) {
 474                         vga_cleanup(state);
 475                         return 1;
 476                 }
 477                 restore_vga_text(state, fbbase);
 478                 iounmap(fbbase);
 479         }
 480
 481         if (state->flags & VGA_SAVE_CMAP)
 482                 restore_vga_cmap(state);
 483
 484         vga_cleanup(state);
 485         return 0;
 486 }
 487
 488 EXPORT_SYMBOL(save_vga);
 489 EXPORT_SYMBOL(restore_vga);
 490
 491 MODULE_AUTHOR("James Simmons <jsimmons@users.sf.net>");
 492 MODULE_DESCRIPTION("VGA State Save/Restore");
 493 MODULE_LICENSE("GPL");
 494