LXR linux/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
  22struct 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
  34static 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
  41static 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
  48static 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
 138static 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
 226static 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
 257static 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
 309static 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
 322static 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
 335static 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
 350int 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
 458int 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
 484EXPORT_SYMBOL(save_vga);
 485EXPORT_SYMBOL(restore_vga);
 486
 487MODULE_AUTHOR("James Simmons <jsimmons@users.sf.net>");
 488MODULE_DESCRIPTION("VGA State Save/Restore");
 489MODULE_LICENSE("GPL");
 490
 491