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/config.h>
  17 #include <linux/module.h>
  18 #include <linux/slab.h>
  19 #include <linux/fb.h>
  20 #include <linux/vmalloc.h>
  21 #include <video/vga.h>
  22
  23 struct regstate {
  24         __u8 *vga_font0;
  25         __u8 *vga_font1;
  26         __u8 *vga_text;
  27         __u8 *vga_cmap;
  28         __u8 *attr;
  29         __u8 *crtc;
  30         __u8 *gfx;
  31         __u8 *seq;
  32         __u8 misc;
  33 };
  34
  35 static inline unsigned char vga_rcrtcs(void __iomem *regbase, unsigned short iobase,
  36                                        unsigned char reg)
  37 {
  38         vga_w(regbase, iobase + 0x4, reg);
  39         return vga_r(regbase, iobase + 0x5);
  40 }
  41
  42 static inline void vga_wcrtcs(void __iomem *regbase, unsigned short iobase,
  43                               unsigned char reg, unsigned char val)
  44 {
  45         vga_w(regbase, iobase + 0x4, reg);
  46         vga_w(regbase, iobase + 0x5, val);
  47 }
  48
  49 static void save_vga_text(struct vgastate *state, void __iomem *fbbase)
  50 {
  51         struct regstate *saved = (struct regstate *) state->vidstate;
  52         int i;
  53         u8 misc, attr10, gr4, gr5, gr6, seq1, seq2, seq4;
  54
  55         /* if in graphics mode, no need to save */
  56         attr10 = vga_rattr(state->vgabase, 0x10);
  57         if (attr10 & 1)
  58                 return;
  59
  60         /* save regs */
  61         misc = vga_r(state->vgabase, VGA_MIS_R);
  62         gr4 = vga_rgfx(state->vgabase, VGA_GFX_PLANE_READ);
  63         gr5 = vga_rgfx(state->vgabase, VGA_GFX_MODE);
  64         gr6 = vga_rgfx(state->vgabase, VGA_GFX_MISC);
  65         seq2 = vga_rseq(state->vgabase, VGA_SEQ_PLANE_WRITE);
  66         seq4 = vga_rseq(state->vgabase, VGA_SEQ_MEMORY_MODE);
  67
  68         /* force graphics mode */
  69         vga_w(state->vgabase, VGA_MIS_W, misc | 1);
  70
  71         /* blank screen */
  72         seq1 = vga_rseq(state->vgabase, VGA_SEQ_CLOCK_MODE);
  73         vga_wseq(state->vgabase, VGA_SEQ_RESET, 0x1);
  74         vga_wseq(state->vgabase, VGA_SEQ_CLOCK_MODE, seq1 | 1 << 5);
  75         vga_wseq(state->vgabase, VGA_SEQ_RESET, 0x3);
  76
  77         /* save font at plane 2 */
  78         if (state->flags & VGA_SAVE_FONT0) {
  79                 vga_wseq(state->vgabase, VGA_SEQ_PLANE_WRITE, 0x4);
  80                 vga_wseq(state->vgabase, VGA_SEQ_MEMORY_MODE, 0x6);
  81                 vga_wgfx(state->vgabase, VGA_GFX_PLANE_READ, 0x2);
  82                 vga_wgfx(state->vgabase, VGA_GFX_MODE, 0x0);
  83                 vga_wgfx(state->vgabase, VGA_GFX_MISC, 0x5);
  84                 for (i = 0; i < 4 * 8192; i++)
  85                         saved->vga_font0[i] = vga_r(fbbase, i);
  86         }
  87
  88         /* save font at plane 3 */
  89         if (state->flags & VGA_SAVE_FONT1) {
  90                 vga_wseq(state->vgabase, VGA_SEQ_PLANE_WRITE, 0x8);
  91                 vga_wseq(state->vgabase, VGA_SEQ_MEMORY_MODE, 0x6);
  92                 vga_wgfx(state->vgabase, VGA_GFX_PLANE_READ, 0x3);
  93                 vga_wgfx(state->vgabase, VGA_GFX_MODE, 0x0);
  94                 vga_wgfx(state->vgabase, VGA_GFX_MISC, 0x5);
  95                 for (i = 0; i < state->memsize; i++)
  96                         saved->vga_font1[i] = vga_r(fbbase, i);
  97         }
  98
  99         /* save font at plane 0/1 */
 100         if (state->flags & VGA_SAVE_TEXT) {
 101                 vga_wseq(state->vgabase, VGA_SEQ_PLANE_WRITE, 0x1);
 102                 vga_wseq(state->vgabase, VGA_SEQ_MEMORY_MODE, 0x6);
 103                 vga_wgfx(state->vgabase, VGA_GFX_PLANE_READ, 0x0);
 104                 vga_wgfx(state->vgabase, VGA_GFX_MODE, 0x0);
 105                 vga_wgfx(state->vgabase, VGA_GFX_MISC, 0x5);
 106                 for (i = 0; i < 8192; i++)
 107                         saved->vga_text[i] = vga_r(fbbase, i);
 108
 109                 vga_wseq(state->vgabase, VGA_SEQ_PLANE_WRITE, 0x2);
 110                 vga_wseq(state->vgabase, VGA_SEQ_MEMORY_MODE, 0x6);
 111                 vga_wgfx(state->vgabase, VGA_GFX_PLANE_READ, 0x1);
 112                 vga_wgfx(state->vgabase, VGA_GFX_MODE, 0x0);
 113                 vga_wgfx(state->vgabase, VGA_GFX_MISC, 0x5);
 114                 for (i = 0; i < 8192; i++)
 115                         saved->vga_text[8192+i] = vga_r(fbbase + 2 * 8192, i);
 116         }
 117
 118         /* restore regs */
 119         vga_wattr(state->vgabase, 0x10, attr10);
 120
 121         vga_wseq(state->vgabase, VGA_SEQ_PLANE_WRITE, seq2);
 122         vga_wseq(state->vgabase, VGA_SEQ_MEMORY_MODE, seq4);
 123
 124         vga_wgfx(state->vgabase, VGA_GFX_PLANE_READ, gr4);
 125         vga_wgfx(state->vgabase, VGA_GFX_MODE, gr5);
 126         vga_wgfx(state->vgabase, VGA_GFX_MISC, gr6);
 127         vga_w(state->vgabase, VGA_MIS_W, misc);
 128
 129         /* unblank screen */
 130         vga_wseq(state->vgabase, VGA_SEQ_RESET, 0x1);
 131         vga_wseq(state->vgabase, VGA_SEQ_CLOCK_MODE, seq1 & ~(1 << 5));
 132         vga_wseq(state->vgabase, VGA_SEQ_RESET, 0x3);
 133
 134         vga_wseq(state->vgabase, VGA_SEQ_CLOCK_MODE, seq1);
 135 }
 136
 137 static void restore_vga_text(struct vgastate *state, void __iomem *fbbase)
 138 {
 139         struct regstate *saved = (struct regstate *) state->vidstate;
 140         int i;
 141         u8 misc, gr1, gr3, gr4, gr5, gr6, gr8;
 142         u8 seq1, seq2, seq4;
 143
 144         /* save regs */
 145         misc = vga_r(state->vgabase, VGA_MIS_R);
 146         gr1 = vga_rgfx(state->vgabase, VGA_GFX_SR_ENABLE);
 147         gr3 = vga_rgfx(state->vgabase, VGA_GFX_DATA_ROTATE);
 148         gr4 = vga_rgfx(state->vgabase, VGA_GFX_PLANE_READ);
 149         gr5 = vga_rgfx(state->vgabase, VGA_GFX_MODE);
 150         gr6 = vga_rgfx(state->vgabase, VGA_GFX_MISC);
 151         gr8 = vga_rgfx(state->vgabase, VGA_GFX_BIT_MASK);
 152         seq2 = vga_rseq(state->vgabase, VGA_SEQ_PLANE_WRITE);
 153         seq4 = vga_rseq(state->vgabase, VGA_SEQ_MEMORY_MODE);
 154
 155         /* force graphics mode */
 156         vga_w(state->vgabase, VGA_MIS_W, misc | 1);
 157
 158         /* blank screen */
 159         seq1 = vga_rseq(state->vgabase, VGA_SEQ_CLOCK_MODE);
 160         vga_wseq(state->vgabase, VGA_SEQ_RESET, 0x1);
 161         vga_wseq(state->vgabase, VGA_SEQ_CLOCK_MODE, seq1 | 1 << 5);
 162         vga_wseq(state->vgabase, VGA_SEQ_RESET, 0x3);
 163
 164         if (state->depth == 4) {
 165                 vga_wgfx(state->vgabase, VGA_GFX_DATA_ROTATE, 0x0);
 166                 vga_wgfx(state->vgabase, VGA_GFX_BIT_MASK, 0xff);
 167                 vga_wgfx(state->vgabase, VGA_GFX_SR_ENABLE, 0x00);
 168         }
 169
 170         /* restore font at plane 2 */
 171         if (state->flags & VGA_SAVE_FONT0) {
 172                 vga_wseq(state->vgabase, VGA_SEQ_PLANE_WRITE, 0x4);
 173                 vga_wseq(state->vgabase, VGA_SEQ_MEMORY_MODE, 0x6);
 174                 vga_wgfx(state->vgabase, VGA_GFX_PLANE_READ, 0x2);
 175                 vga_wgfx(state->vgabase, VGA_GFX_MODE, 0x0);
 176                 vga_wgfx(state->vgabase, VGA_GFX_MISC, 0x5);
 177                 for (i = 0; i < 4 * 8192; i++)
 178                         vga_w(fbbase, i, saved->vga_font0[i]);
 179         }
 180
 181         /* restore font at plane 3 */
 182         if (state->flags & VGA_SAVE_FONT1) {
 183                 vga_wseq(state->vgabase, VGA_SEQ_PLANE_WRITE, 0x8);
 184                 vga_wseq(state->vgabase, VGA_SEQ_MEMORY_MODE, 0x6);
 185                 vga_wgfx(state->vgabase, VGA_GFX_PLANE_READ, 0x3);
 186                 vga_wgfx(state->vgabase, VGA_GFX_MODE, 0x0);
 187                 vga_wgfx(state->vgabase, VGA_GFX_MISC, 0x5);
 188                 for (i = 0; i < state->memsize; i++)
 189                         vga_w(fbbase, i, saved->vga_font1[i]);
 190         }
 191
 192         /* restore font at plane 0/1 */
 193         if (state->flags & VGA_SAVE_TEXT) {
 194                 vga_wseq(state->vgabase, VGA_SEQ_PLANE_WRITE, 0x1);
 195                 vga_wseq(state->vgabase, VGA_SEQ_MEMORY_MODE, 0x6);
 196                 vga_wgfx(state->vgabase, VGA_GFX_PLANE_READ, 0x0);
 197                 vga_wgfx(state->vgabase, VGA_GFX_MODE, 0x0);
 198                 vga_wgfx(state->vgabase, VGA_GFX_MISC, 0x5);
 199                 for (i = 0; i < 8192; i++)
 200                         vga_w(fbbase, i, saved->vga_text[i]);
 201
 202                 vga_wseq(state->vgabase, VGA_SEQ_PLANE_WRITE, 0x2);
 203                 vga_wseq(state->vgabase, VGA_SEQ_MEMORY_MODE, 0x6);
 204                 vga_wgfx(state->vgabase, VGA_GFX_PLANE_READ, 0x1);
 205                 vga_wgfx(state->vgabase, VGA_GFX_MODE, 0x0);
 206                 vga_wgfx(state->vgabase, VGA_GFX_MISC, 0x5);
 207                 for (i = 0; i < 8192; i++)
 208                         vga_w(fbbase, i, saved->vga_text[8192+i]);
 209         }
 210
 211         /* unblank screen */
 212         vga_wseq(state->vgabase, VGA_SEQ_RESET, 0x1);
 213         vga_wseq(state->vgabase, VGA_SEQ_CLOCK_MODE, seq1 & ~(1 << 5));
 214         vga_wseq(state->vgabase, VGA_SEQ_RESET, 0x3);
 215
 216         /* restore regs */
 217         vga_w(state->vgabase, VGA_MIS_W, misc);
 218
 219         vga_wgfx(state->vgabase, VGA_GFX_SR_ENABLE, gr1);
 220         vga_wgfx(state->vgabase, VGA_GFX_DATA_ROTATE, gr3);
 221         vga_wgfx(state->vgabase, VGA_GFX_PLANE_READ, gr4);
 222         vga_wgfx(state->vgabase, VGA_GFX_MODE, gr5);
 223         vga_wgfx(state->vgabase, VGA_GFX_MISC, gr6);
 224         vga_wgfx(state->vgabase, VGA_GFX_BIT_MASK, gr8);
 225
 226         vga_wseq(state->vgabase, VGA_SEQ_CLOCK_MODE, seq1);
 227         vga_wseq(state->vgabase, VGA_SEQ_PLANE_WRITE, seq2);
 228         vga_wseq(state->vgabase, VGA_SEQ_MEMORY_MODE, seq4);
 229 }
 230
 231 static void save_vga_mode(struct vgastate *state)
 232 {
 233         struct regstate *saved = (struct regstate *) state->vidstate;
 234         unsigned short iobase;
 235         int i;
 236
 237         saved->misc = vga_r(state->vgabase, VGA_MIS_R);
 238         if (saved->misc & 1)
 239                 iobase = 0x3d0;
 240         else
 241                 iobase = 0x3b0;
 242
 243         for (i = 0; i < state->num_crtc; i++)
 244                 saved->crtc[i] = vga_rcrtcs(state->vgabase, iobase, i);
 245
 246         vga_r(state->vgabase, iobase + 0xa);
 247         vga_w(state->vgabase, VGA_ATT_W, 0x00);
 248         for (i = 0; i < state->num_attr; i++) {
 249                 vga_r(state->vgabase, iobase + 0xa);
 250                 saved->attr[i] = vga_rattr(state->vgabase, i);
 251         }
 252         vga_r(state->vgabase, iobase + 0xa);
 253         vga_w(state->vgabase, VGA_ATT_W, 0x20);
 254
 255         for (i = 0; i < state->num_gfx; i++)
 256                 saved->gfx[i] = vga_rgfx(state->vgabase, i);
 257
 258         for (i = 0; i < state->num_seq; i++)
 259                 saved->seq[i] = vga_rseq(state->vgabase, i);
 260 }
 261
 262 static void restore_vga_mode(struct vgastate *state)
 263 {
 264         struct regstate *saved = (struct regstate *) state->vidstate;
 265         unsigned short iobase;
 266         int i;
 267
 268         vga_w(state->vgabase, VGA_MIS_W, saved->misc);
 269
 270         if (saved->misc & 1)
 271                 iobase = 0x3d0;
 272         else
 273                 iobase = 0x3b0;
 274
 275         /* turn off display */
 276         vga_wseq(state->vgabase, VGA_SEQ_CLOCK_MODE,
 277                  saved->seq[VGA_SEQ_CLOCK_MODE] | 0x20);
 278
 279         /* disable sequencer */
 280         vga_wseq(state->vgabase, VGA_SEQ_RESET, 0x01);
 281
 282         /* enable palette addressing */
 283         vga_r(state->vgabase, iobase + 0xa);
 284         vga_w(state->vgabase, VGA_ATT_W, 0x00);
 285
 286         for (i = 2; i < state->num_seq; i++)
 287                 vga_wseq(state->vgabase, i, saved->seq[i]);
 288
 289
 290         /* unprotect vga regs */
 291         vga_wcrtcs(state->vgabase, iobase, 17, saved->crtc[17] & ~0x80);
 292         for (i = 0; i < state->num_crtc; i++)
 293                 vga_wcrtcs(state->vgabase, iobase, i, saved->crtc[i]);
 294
 295         for (i = 0; i < state->num_gfx; i++)
 296                 vga_wgfx(state->vgabase, i, saved->gfx[i]);
 297
 298         for (i = 0; i < state->num_attr; i++) {
 299                 vga_r(state->vgabase, iobase + 0xa);
 300                 vga_wattr(state->vgabase, i, saved->attr[i]);
 301         }
 302
 303         /* reenable sequencer */
 304         vga_wseq(state->vgabase, VGA_SEQ_RESET, 0x03);
 305         /* turn display on */
 306         vga_wseq(state->vgabase, VGA_SEQ_CLOCK_MODE,
 307                  saved->seq[VGA_SEQ_CLOCK_MODE] & ~(1 << 5));
 308
 309         /* disable video/palette source */
 310         vga_r(state->vgabase, iobase + 0xa);
 311         vga_w(state->vgabase, VGA_ATT_W, 0x20);
 312 }
 313
 314 static void save_vga_cmap(struct vgastate *state)
 315 {
 316         struct regstate *saved = (struct regstate *) state->vidstate;
 317         int i;
 318
 319         vga_w(state->vgabase, VGA_PEL_MSK, 0xff);
 320
 321         /* assumes DAC is readable and writable */
 322         vga_w(state->vgabase, VGA_PEL_IR, 0x00);
 323         for (i = 0; i < 768; i++)
 324                 saved->vga_cmap[i] = vga_r(state->vgabase, VGA_PEL_D);
 325 }
 326
 327 static void restore_vga_cmap(struct vgastate *state)
 328 {
 329         struct regstate *saved = (struct regstate *) state->vidstate;
 330         int i;
 331
 332         vga_w(state->vgabase, VGA_PEL_MSK, 0xff);
 333
 334         /* assumes DAC is readable and writable */
 335         vga_w(state->vgabase, VGA_PEL_IW, 0x00);
 336         for (i = 0; i < 768; i++)
 337                 vga_w(state->vgabase, VGA_PEL_D, saved->vga_cmap[i]);
 338 }
 339
 340 static void vga_cleanup(struct vgastate *state)
 341 {
 342         if (state->vidstate != NULL) {
 343                 struct regstate *saved = (struct regstate *) state->vidstate;
 344
 345                 vfree(saved->vga_font0);
 346                 vfree(saved->vga_font1);
 347                 vfree(saved->vga_text);
 348                 vfree(saved->vga_cmap);
 349                 vfree(saved->attr);
 350                 kfree(saved);
 351                 state->vidstate = NULL;
 352         }
 353 }
 354
 355 int save_vga(struct vgastate *state)
 356 {
 357         struct regstate *saved;
 358
 359         saved = kzalloc(sizeof(struct regstate), GFP_KERNEL);
 360
 361         if (saved == NULL)
 362                 return 1;
 363
 364         state->vidstate = (void *)saved;
 365
 366         if (state->flags & VGA_SAVE_CMAP) {
 367                 saved->vga_cmap = vmalloc(768);
 368                 if (!saved->vga_cmap) {
 369                         vga_cleanup(state);
 370                         return 1;
 371                 }
 372                 save_vga_cmap(state);
 373         }
 374
 375         if (state->flags & VGA_SAVE_MODE) {
 376                 int total;
 377
 378                 if (state->num_attr < 21)
 379                         state->num_attr = 21;
 380                 if (state->num_crtc < 25)
 381                         state->num_crtc = 25;
 382                 if (state->num_gfx < 9)
 383                         state->num_gfx = 9;
 384                 if (state->num_seq < 5)
 385                         state->num_seq = 5;
 386                 total = state->num_attr + state->num_crtc +
 387                         state->num_gfx + state->num_seq;
 388
 389                 saved->attr = vmalloc(total);
 390                 if (!saved->attr) {
 391                         vga_cleanup(state);
 392                         return 1;
 393                 }
 394                 saved->crtc = saved->attr + state->num_attr;
 395                 saved->gfx = saved->crtc + state->num_crtc;
 396                 saved->seq = saved->gfx + state->num_gfx;
 397
 398                 save_vga_mode(state);
 399         }
 400
 401         if (state->flags & VGA_SAVE_FONTS) {
 402                 void __iomem *fbbase;
 403
 404                 /* exit if window is less than 32K */
 405                 if (state->memsize && state->memsize < 4 * 8192) {
 406                         vga_cleanup(state);
 407                         return 1;
 408                 }
 409                 if (!state->memsize)
 410                         state->memsize = 8 * 8192;
 411
 412                 if (!state->membase)
 413                         state->membase = 0xA0000;
 414
 415                 fbbase = ioremap(state->membase, state->memsize);
 416
 417                 if (!fbbase) {
 418                         vga_cleanup(state);
 419                         return 1;
 420                 }
 421
 422                 /*
 423                  * save only first 32K used by vgacon
 424                  */
 425                 if (state->flags & VGA_SAVE_FONT0) {
 426                         saved->vga_font0 = vmalloc(4 * 8192);
 427                         if (!saved->vga_font0) {
 428                                 iounmap(fbbase);
 429                                 vga_cleanup(state);
 430                                 return 1;
 431                         }
 432                 }
 433                 /*
 434                  * largely unused, but if required by the caller
 435                  * we'll just save everything.
 436                  */
 437                 if (state->flags & VGA_SAVE_FONT1) {
 438                         saved->vga_font1 = vmalloc(state->memsize);
 439                         if (!saved->vga_font1) {
 440                                 iounmap(fbbase);
 441                                 vga_cleanup(state);
 442                                 return 1;
 443                         }
 444                 }
 445                 /*
 446                  * Save 8K at plane0[0], and 8K at plane1[16K]
 447                  */
 448                 if (state->flags & VGA_SAVE_TEXT) {
 449                         saved->vga_text = vmalloc(8192 * 2);
 450                         if (!saved->vga_text) {
 451                                 iounmap(fbbase);
 452                                 vga_cleanup(state);
 453                                 return 1;
 454                         }
 455                 }
 456
 457                 save_vga_text(state, fbbase);
 458                 iounmap(fbbase);
 459         }
 460         return 0;
 461 }
 462
 463 int restore_vga (struct vgastate *state)
 464 {
 465         if (state->vidstate == NULL)
 466                 return 1;
 467
 468         if (state->flags & VGA_SAVE_MODE)
 469                 restore_vga_mode(state);
 470
 471         if (state->flags & VGA_SAVE_FONTS) {
 472                 void __iomem *fbbase = ioremap(state->membase, state->memsize);
 473
 474                 if (!fbbase) {
 475                         vga_cleanup(state);
 476                         return 1;
 477                 }
 478                 restore_vga_text(state, fbbase);
 479                 iounmap(fbbase);
 480         }
 481
 482         if (state->flags & VGA_SAVE_CMAP)
 483                 restore_vga_cmap(state);
 484
 485         vga_cleanup(state);
 486         return 0;
 487 }
 488
 489 EXPORT_SYMBOL(save_vga);
 490 EXPORT_SYMBOL(restore_vga);
 491
 492 MODULE_AUTHOR("James Simmons <jsimmons@users.sf.net>");
 493 MODULE_DESCRIPTION("VGA State Save/Restore");
 494 MODULE_LICENSE("GPL");
 495