Linux-2.6.12-rc2
[linux-2.6.git] / 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                 if (saved->vga_font0) 
346                         vfree(saved->vga_font0);
347                 if (saved->vga_font1) 
348                         vfree(saved->vga_font1);
349                 if (saved->vga_text)
350                         vfree(saved->vga_text);
351                 if (saved->vga_cmap)
352                         vfree(saved->vga_cmap);
353                 if (saved->attr)
354                         vfree(saved->attr);
355                 kfree(saved);
356                 state->vidstate = NULL;
357         }
358 }
359                 
360 int save_vga(struct vgastate *state)
361 {
362         struct regstate *saved;
363
364         saved = kmalloc(sizeof(struct regstate), GFP_KERNEL);
365         if (saved == NULL)
366                 return 1;
367         memset (saved, 0, sizeof(struct regstate));
368         state->vidstate = (void *)saved;
369                 
370         if (state->flags & VGA_SAVE_CMAP) {
371                 saved->vga_cmap = vmalloc(768);
372                 if (!saved->vga_cmap) {
373                         vga_cleanup(state);
374                         return 1;
375                 }
376                 save_vga_cmap(state);
377         }
378
379         if (state->flags & VGA_SAVE_MODE) {
380                 int total;
381
382                 if (state->num_attr < 21)
383                         state->num_attr = 21;
384                 if (state->num_crtc < 25)
385                         state->num_crtc = 25;
386                 if (state->num_gfx < 9)
387                         state->num_gfx = 9;
388                 if (state->num_seq < 5)
389                         state->num_seq = 5;
390                 total = state->num_attr + state->num_crtc +
391                         state->num_gfx + state->num_seq;
392
393                 saved->attr = vmalloc(total);
394                 if (!saved->attr) {
395                         vga_cleanup(state);
396                         return 1;
397                 }
398                 saved->crtc = saved->attr + state->num_attr;
399                 saved->gfx = saved->crtc + state->num_crtc;
400                 saved->seq = saved->gfx + state->num_gfx;
401
402                 save_vga_mode(state);
403         }
404
405         if (state->flags & VGA_SAVE_FONTS) {
406                 void __iomem *fbbase;
407
408                 /* exit if window is less than 32K */
409                 if (state->memsize && state->memsize < 4 * 8192) {
410                         vga_cleanup(state);
411                         return 1;
412                 }
413                 if (!state->memsize)
414                         state->memsize = 8 * 8192;
415                 
416                 if (!state->membase)
417                         state->membase = 0xA0000;
418
419                 fbbase = ioremap(state->membase, state->memsize);
420
421                 if (!fbbase) {
422                         vga_cleanup(state);
423                         return 1;
424                 }
425
426                 /* 
427                  * save only first 32K used by vgacon
428                  */
429                 if (state->flags & VGA_SAVE_FONT0) {
430                         saved->vga_font0 = vmalloc(4 * 8192);
431                         if (!saved->vga_font0) {
432                                 iounmap(fbbase);
433                                 vga_cleanup(state);
434                                 return 1;
435                         }
436                 }
437                 /* 
438                  * largely unused, but if required by the caller
439                  * we'll just save everything.
440                  */
441                 if (state->flags & VGA_SAVE_FONT1) {
442                         saved->vga_font1 = vmalloc(state->memsize);
443                         if (!saved->vga_font1) {
444                                 iounmap(fbbase);
445                                 vga_cleanup(state);
446                                 return 1;
447                         }
448                 }
449                 /*
450                  * Save 8K at plane0[0], and 8K at plane1[16K]
451                  */
452                 if (state->flags & VGA_SAVE_TEXT) {
453                         saved->vga_text = vmalloc(8192 * 2);
454                         if (!saved->vga_text) {
455                                 iounmap(fbbase);
456                                 vga_cleanup(state);
457                                 return 1;
458                         }
459                 }
460                 
461                 save_vga_text(state, fbbase);
462                 iounmap(fbbase);
463         }
464         return 0;
465 }
466
467 int restore_vga (struct vgastate *state)
468 {
469         if (state->vidstate == NULL)
470                 return 1;
471
472         if (state->flags & VGA_SAVE_MODE)
473                 restore_vga_mode(state);
474
475         if (state->flags & VGA_SAVE_FONTS) {
476                 void __iomem *fbbase = ioremap(state->membase, state->memsize);
477
478                 if (!fbbase) {
479                         vga_cleanup(state);
480                         return 1;
481                 }
482                 restore_vga_text(state, fbbase);
483                 iounmap(fbbase);
484         }
485
486         if (state->flags & VGA_SAVE_CMAP)
487                 restore_vga_cmap(state);
488
489         vga_cleanup(state);
490         return 0;
491 }
492
493 #ifdef MODULE
494 int init_module(void) { return 0; };
495 void cleanup_module(void) {};
496 #endif
497
498 EXPORT_SYMBOL(save_vga);
499 EXPORT_SYMBOL(restore_vga);
500
501 MODULE_AUTHOR("James Simmons <jsimmons@users.sf.net>");
502 MODULE_DESCRIPTION("VGA State Save/Restore");
503 MODULE_LICENSE("GPL");
504