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