aboutsummaryrefslogtreecommitdiff
path: root/drivers/video/console/vgacon.c
blob: f65bcd314d54118b0b8d5fd69847fd060a352f69 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904
905
906
907
908
909
910
911
912
913
914
915
916
917
918
919
920
921
922
923
924
925
926
927
928
929
930
931
932
933
934
935
936
937
938
939
940
941
942
943
944
945
946
947
948
949
950
951
952
953
954
955
956
957
958
959
960
961
962
963
964
965
966
967
968
969
970
971
972
973
974
975
976
977
978
979
980
981
982
983
984
985
986
987
988
989
990
991
992
993
994
995
996
997
998
999
1000
1001
1002
1003
1004
1005
1006
1007
1008
1009
1010
1011
1012
1013
1014
1015
1016
1017
1018
1019
1020
1021
1022
1023
1024
1025
1026
1027
1028
1029
1030
1031
1032
1033
1034
1035
1036
1037
1038
1039
1040
1041
1042
1043
1044
1045
1046
1047
1048
1049
1050
1051
1052
1053
1054
1055
1056
1057
1058
1059
1060
1061
1062
1063
1064
1065
1066
1067
1068
1069
1070
1071
1072
1073
1074
1075
1076
1077
1078
1079
1080
1081
1082
1083
1084
1085
1086
1087
1088
1089
1090
1091
1092
1093
1094
1095
1096
1097
1098
1099
1100
1101
1102
1103
1104
1105
1106
1107
1108
1109
1110
1111
1112
1113
1114
1115
1116
1117
1118
1119
1120
1121
1122
1123
1124
1125
1126
1127
1128
1129
1130
1131
1132
1133
1134
1135
1136
1137
1138
1139
1140
1141
1142
1143
1144
1145
1146
1147
1148
1149
1150
1151
1152
1153
1154
1155
1156
1157
1158
1159
1160
1161
1162
1163
1164
1165
1166
1167
1168
1169
1170
1171
1172
1173
1174
1175
1176
1177
1178
1179
1180
1181
1182
1183
1184
1185
1186
1187
1188
1189
1190
1191
1192
1193
1194
1195
1196
1197
1198
1199
1200
1201
1202
1203
1204
1205
1206
1207
1208
1209
1210
1211
1212
1213
1214
1215
1216
1217
1218
1219
1220
1221
1222
1223
1224
1225
1226
1227
1228
1229
1230
1231
1232
1233
1234
1235
1236
1237
1238
1239
1240
1241
1242
1243
1244
1245
1246
1247
1248
1249
1250
1251
1252
1253
1254
1255
1256
1257
1258
1259
1260
1261
1262
1263
1264
1265
1266
1267
1268
1269
1270
1271
1272
1273
1274
1275
1276
1277
1278
1279
1280
1281
1282
1283
1284
1285
1286
1287
1288
1289
1290
1291
1292
1293
1294
1295
1296
1297
1298
1299
1300
1301
1302
1303
1304
1305
1306
1307
1308
1309
1310
1311
1312
1313
1314
1315
1316
1317
1318
1319
1320
1321
1322
1323
1324
1325
1326
1327
1328
1329
1330
1331
1332
1333
1334
1335
1336
1337
1338
1339
1340
1341
1342
1343
1344
1345
1346
1347
1348
1349
1350
1351
1352
1353
1354
1355
1356
1357
1358
1359
1360
1361
1362
1363
1364
1365
1366
1367
1368
1369
1370
1371
1372
1373
1374
1375
1376
1377
1378
1379
1380
1381
1382
1383
1384
1385
1386
1387
1388
1389
1390
1391
1392
1393
1394
1395
1396
1397
1398
1399
1400
1401
1402
1403
1404
1405
1406
1407
1408
1409
1410
1411
1412
1413
1414
/*
 *  linux/drivers/video/vgacon.c -- Low level VGA based console driver
 *
 *	Created 28 Sep 1997 by Geert Uytterhoeven
 *
 *	Rewritten by Martin Mares <mj@ucw.cz>, July 1998
 *
 *  This file is based on the old console.c, vga.c and vesa_blank.c drivers.
 *
 *	Copyright (C) 1991, 1992  Linus Torvalds
 *			    1995  Jay Estabrook
 *
 *	User definable mapping table and font loading by Eugene G. Crosser,
 *	<crosser@average.org>
 *
 *	Improved loadable font/UTF-8 support by H. Peter Anvin
 *	Feb-Sep 1995 <peter.anvin@linux.org>
 *
 *	Colour palette handling, by Simon Tatham
 *	17-Jun-95 <sgt20@cam.ac.uk>
 *
 *	if 512 char mode is already enabled don't re-enable it,
 *	because it causes screen to flicker, by Mitja Horvat
 *	5-May-96 <mitja.horvat@guest.arnes.si>
 *
 *	Use 2 outw instead of 4 outb_p to reduce erroneous text
 *	flashing on RHS of screen during heavy console scrolling .
 *	Oct 1996, Paul Gortmaker.
 *
 *
 *  This file is subject to the terms and conditions of the GNU General Public
 *  License.  See the file COPYING in the main directory of this archive for
 *  more details.
 */

#include <linux/module.h>
#include <linux/types.h>
#include <linux/fs.h>
#include <linux/kernel.h>
#include <linux/console.h>
#include <linux/string.h>
#include <linux/kd.h>
#include <linux/slab.h>
#include <linux/vt_kern.h>
#include <linux/selection.h>
#include <linux/spinlock.h>
#include <linux/ioport.h>
#include <linux/init.h>
#include <linux/screen_info.h>
#include <linux/smp_lock.h>
#include <video/vga.h>
#include <asm/io.h>

static DEFINE_SPINLOCK(vga_lock);
static int cursor_size_lastfrom;
static int cursor_size_lastto;
static u32 vgacon_xres;
static u32 vgacon_yres;
static struct vgastate state;

#define BLANK 0x0020

#define CAN_LOAD_EGA_FONTS	/* undefine if the user must not do this */
#define CAN_LOAD_PALETTE	/* undefine if the user must not do this */

/* You really do _NOT_ want to define this, unless you have buggy
 * Trident VGA which will resize cursor when moving it between column
 * 15 & 16. If you define this and your VGA is OK, inverse bug will
 * appear.
 */
#undef TRIDENT_GLITCH
#define VGA_FONTWIDTH       8   /* VGA does not support fontwidths != 8 */
/*
 *  Interface used by the world
 */

static const char *vgacon_startup(void);
static void vgacon_init(struct vc_data *c, int init);
static void vgacon_deinit(struct vc_data *c);
static void vgacon_cursor(struct vc_data *c, int mode);
static int vgacon_switch(struct vc_data *c);
static int vgacon_blank(struct vc_data *c, int blank, int mode_switch);
static int vgacon_set_palette(struct vc_data *vc, unsigned char *table);
static int vgacon_scrolldelta(struct vc_data *c, int lines);
static int vgacon_set_origin(struct vc_data *c);
static void vgacon_save_screen(struct vc_data *c);
static int vgacon_scroll(struct vc_data *c, int t, int b, int dir,
			 int lines);
static void vgacon_invert_region(struct vc_data *c, u16 * p, int count);
static unsigned long vgacon_uni_pagedir[2];

/* Description of the hardware situation */
static int		vga_init_done		__read_mostly;
static unsigned long	vga_vram_base		__read_mostly;	/* Base of video memory */
static unsigned long	vga_vram_end		__read_mostly;	/* End of video memory */
static unsigned int	vga_vram_size		__read_mostly;	/* Size of video memory */
static u16		vga_video_port_reg	__read_mostly;	/* Video register select port */
static u16		vga_video_port_val	__read_mostly;	/* Video register value port */
static unsigned int	vga_video_num_columns;			/* Number of text columns */
static unsigned int	vga_video_num_lines;			/* Number of text lines */
static int		vga_can_do_color	__read_mostly;	/* Do we support colors? */
static unsigned int	vga_default_font_height __read_mostly;	/* Height of default screen font */
static unsigned char	vga_video_type		__read_mostly;	/* Card type */
static unsigned char	vga_hardscroll_enabled	__read_mostly;
static unsigned char	vga_hardscroll_user_enable __read_mostly = 1;
static unsigned char	vga_font_is_default = 1;
static int		vga_vesa_blanked;
static int 		vga_palette_blanked;
static int 		vga_is_gfx;
static int 		vga_512_chars;
static int 		vga_video_font_height;
static int 		vga_scan_lines		__read_mostly;
static unsigned int 	vga_rolled_over;

static int __init no_scroll(char *str)
{
	/*
	 * Disabling scrollback is required for the Braillex ib80-piezo
	 * Braille reader made by F.H. Papenmeier (Germany).
	 * Use the "no-scroll" bootflag.
	 */
	vga_hardscroll_user_enable = vga_hardscroll_enabled = 0;
	return 1;
}

__setup("no-scroll", no_scroll);

/*
 * By replacing the four outb_p with two back to back outw, we can reduce
 * the window of opportunity to see text mislocated to the RHS of the
 * console during heavy scrolling activity. However there is the remote
 * possibility that some pre-dinosaur hardware won't like the back to back
 * I/O. Since the Xservers get away with it, we should be able to as well.
 */
static inline void write_vga(unsigned char reg, unsigned int val)
{
	unsigned int v1, v2;
	unsigned long flags;

	/*
	 * ddprintk might set the console position from interrupt
	 * handlers, thus the write has to be IRQ-atomic.
	 */
	spin_lock_irqsave(&vga_lock, flags);

#ifndef SLOW_VGA
	v1 = reg + (val & 0xff00);
	v2 = reg + 1 + ((val << 8) & 0xff00);
	outw(v1, vga_video_port_reg);
	outw(v2, vga_video_port_reg);
#else
	outb_p(reg, vga_video_port_reg);
	outb_p(val >> 8, vga_video_port_val);
	outb_p(reg + 1, vga_video_port_reg);
	outb_p(val & 0xff, vga_video_port_val);
#endif
	spin_unlock_irqrestore(&vga_lock, flags);
}

static inline void vga_set_mem_top(struct vc_data *c)
{
	write_vga(12, (c->vc_visible_origin - vga_vram_base) / 2);
}

#ifdef CONFIG_VGACON_SOFT_SCROLLBACK
#include <linux/bootmem.h>
/* software scrollback */
static void *vgacon_scrollback;
static int vgacon_scrollback_tail;
static int vgacon_scrollback_size;
static int vgacon_scrollback_rows;
static int vgacon_scrollback_cnt;
static int vgacon_scrollback_cur;
static int vgacon_scrollback_save;
static int vgacon_scrollback_restore;

static void vgacon_scrollback_init(int pitch)
{
	int rows = CONFIG_VGACON_SOFT_SCROLLBACK_SIZE * 1024/pitch;

	if (vgacon_scrollback) {
		vgacon_scrollback_cnt  = 0;
		vgacon_scrollback_tail = 0;
		vgacon_scrollback_cur  = 0;
		vgacon_scrollback_rows = rows - 1;
		vgacon_scrollback_size = rows * pitch;
	}
}

/*
 * Called only duing init so call of alloc_bootmen is ok.
 * Marked __init_refok to silence modpost.
 */
static void __init_refok vgacon_scrollback_startup(void)
{
	vgacon_scrollback = alloc_bootmem(CONFIG_VGACON_SOFT_SCROLLBACK_SIZE
					  * 1024);
	vgacon_scrollback_init(vga_video_num_columns * 2);
}

static void vgacon_scrollback_update(struct vc_data *c, int t, int count)
{
	void *p;

	if (!vgacon_scrollback_size || c->vc_num != fg_console)
		return;

	p = (void *) (c->vc_origin + t * c->vc_size_row);

	while (count--) {
		scr_memcpyw(vgacon_scrollback + vgacon_scrollback_tail,
			    p, c->vc_size_row);
		vgacon_scrollback_cnt++;
		p += c->vc_size_row;
		vgacon_scrollback_tail += c->vc_size_row;

		if (vgacon_scrollback_tail >= vgacon_scrollback_size)
			vgacon_scrollback_tail = 0;

		if (vgacon_scrollback_cnt > vgacon_scrollback_rows)
			vgacon_scrollback_cnt = vgacon_scrollback_rows;

		vgacon_scrollback_cur = vgacon_scrollback_cnt;
	}
}

static void vgacon_restore_screen(struct vc_data *c)
{
	vgacon_scrollback_save = 0;

	if (!vga_is_gfx && !vgacon_scrollback_restore) {
		scr_memcpyw((u16 *) c->vc_origin, (u16 *) c->vc_screenbuf,
			    c->vc_screenbuf_size > vga_vram_size ?
			    vga_vram_size : c->vc_screenbuf_size);
		vgacon_scrollback_restore = 1;
		vgacon_scrollback_cur = vgacon_scrollback_cnt;
	}
}

static int vgacon_scrolldelta(struct vc_data *c, int lines)
{
	int start, end, count, soff, diff;
	void *d, *s;

	if (!lines) {
		c->vc_visible_origin = c->vc_origin;
		vga_set_mem_top(c);
		return 1;
	}

	if (!vgacon_scrollback)
		return 1;

	if (!vgacon_scrollback_save) {
		vgacon_cursor(c, CM_ERASE);
		vgacon_save_screen(c);
		vgacon_scrollback_save = 1;
	}

	vgacon_scrollback_restore = 0;
	start = vgacon_scrollback_cur + lines;
	end = start + abs(lines);

	if (start < 0)
		start = 0;

	if (start > vgacon_scrollback_cnt)
		start = vgacon_scrollback_cnt;

	if (end < 0)
		end = 0;

	if (end > vgacon_scrollback_cnt)
		end = vgacon_scrollback_cnt;

	vgacon_scrollback_cur = start;
	count = end - start;
	soff = vgacon_scrollback_tail - ((vgacon_scrollback_cnt - end) *
					 c->vc_size_row);
	soff -= count * c->vc_size_row;

	if (soff < 0)
		soff += vgacon_scrollback_size;

	count = vgacon_scrollback_cnt - start;

	if (count > c->vc_rows)
		count = c->vc_rows;

	diff = c->vc_rows - count;

	d = (void *) c->vc_origin;
	s = (void *) c->vc_screenbuf;

	while (count--) {
		scr_memcpyw(d, vgacon_scrollback + soff, c->vc_size_row);
		d += c->vc_size_row;
		soff += c->vc_size_row;

		if (soff >= vgacon_scrollback_size)
			soff = 0;
	}

	if (diff == c->vc_rows) {
		vgacon_cursor(c, CM_MOVE);
	} else {
		while (diff--) {
			scr_memcpyw(d, s, c->vc_size_row);
			d += c->vc_size_row;
			s += c->vc_size_row;
		}
	}

	return 1;
}
#else
#define vgacon_scrollback_startup(...) do { } while (0)
#define vgacon_scrollback_init(...)    do { } while (0)
#define vgacon_scrollback_update(...)  do { } while (0)

static void vgacon_restore_screen(struct vc_data *c)
{
	if (c->vc_origin != c->vc_visible_origin)
		vgacon_scrolldelta(c, 0);
}

static int vgacon_scrolldelta(struct vc_data *c, int lines)
{
	if (!lines)		/* Turn scrollback off */
		c->vc_visible_origin = c->vc_origin;
	else {
		int margin = c->vc_size_row * 4;
		int ul, we, p, st;

		if (vga_rolled_over >
		    (c->vc_scr_end - vga_vram_base) + margin) {
			ul = c->vc_scr_end - vga_vram_base;
			we = vga_rolled_over + c->vc_size_row;
		} else {
			ul = 0;
			we = vga_vram_size;
		}
		p = (c->vc_visible_origin - vga_vram_base - ul + we) % we +
		    lines * c->vc_size_row;
		st = (c->vc_origin - vga_vram_base - ul + we) % we;
		if (st < 2 * margin)
			margin = 0;
		if (p < margin)
			p = 0;
		if (p > st - margin)
			p = st;
		c->vc_visible_origin = vga_vram_base + (p + ul) % we;
	}
	vga_set_mem_top(c);
	return 1;
}
#endif /* CONFIG_VGACON_SOFT_SCROLLBACK */

static const char *vgacon_startup(void)
{
	const char *display_desc = NULL;
	u16 saved1, saved2;
	volatile u16 *p;

	if (screen_info.orig_video_isVGA == VIDEO_TYPE_VLFB) {
	      no_vga:
#ifdef CONFIG_DUMMY_CONSOLE
		conswitchp = &dummy_con;
		return conswitchp->con_startup();
#else
		return NULL;
#endif
	}

	/* boot_params.screen_info initialized? */
	if ((screen_info.orig_video_mode  == 0) &&
	    (screen_info.orig_video_lines == 0) &&
	    (screen_info.orig_video_cols  == 0))
		goto no_vga;

	/* VGA16 modes are not handled by VGACON */
	if ((screen_info.orig_video_mode == 0x0D) ||	/* 320x200/4 */
	    (screen_info.orig_video_mode == 0x0E) ||	/* 640x200/4 */
	    (screen_info.orig_video_mode == 0x10) ||	/* 640x350/4 */
	    (screen_info.orig_video_mode == 0x12) ||	/* 640x480/4 */
	    (screen_info.orig_video_mode == 0x6A))	/* 800x600/4 (VESA) */
		goto no_vga;

	vga_video_num_lines = screen_info.orig_video_lines;
	vga_video_num_columns = screen_info.orig_video_cols;
	state.vgabase = NULL;

	if (screen_info.orig_video_mode == 7) {
		/* Monochrome display */
		vga_vram_base = 0xb0000;
		vga_video_port_reg = VGA_CRT_IM;
		vga_video_port_val = VGA_CRT_DM;
		if ((screen_info.orig_video_ega_bx & 0xff) != 0x10) {
			static struct resource ega_console_resource =
			    { .name = "ega", .start = 0x3B0, .end = 0x3BF };
			vga_video_type = VIDEO_TYPE_EGAM;
			vga_vram_size = 0x8000;
			display_desc = "EGA+";
			request_resource(&ioport_resource,
					 &ega_console_resource);
		} else {
			static struct resource mda1_console_resource =
			    { .name = "mda", .start = 0x3B0, .end = 0x3BB };
			static struct resource mda2_console_resource =
			    { .name = "mda", .start = 0x3BF, .end = 0x3BF };
			vga_video_type = VIDEO_TYPE_MDA;
			vga_vram_size = 0x2000;
			display_desc = "*MDA";
			request_resource(&ioport_resource,
					 &mda1_console_resource);
			request_resource(&ioport_resource,
					 &mda2_console_resource);
			vga_video_font_height = 14;
		}
	} else {
		/* If not, it is color. */
		vga_can_do_color = 1;
		vga_vram_base = 0xb8000;
		vga_video_port_reg = VGA_CRT_IC;
		vga_video_port_val = VGA_CRT_DC;
		if ((screen_info.orig_video_ega_bx & 0xff) != 0x10) {
			int i;

			vga_vram_size = 0x8000;

			if (!screen_info.orig_video_isVGA) {
				static struct resource ega_console_resource
				    = { .name = "ega", .start = 0x3C0, .end = 0x3DF };
				vga_video_type = VIDEO_TYPE_EGAC;
				display_desc = "EGA";
				request_resource(&ioport_resource,
						 &ega_console_resource);
			} else {
				static struct resource vga_console_resource
				    = { .name = "vga+", .start = 0x3C0, .end = 0x3DF };
				vga_video_type = VIDEO_TYPE_VGAC;
				display_desc = "VGA+";
				request_resource(&ioport_resource,
						 &vga_console_resource);

#ifdef VGA_CAN_DO_64KB
				/*
				 * get 64K rather than 32K of video RAM.
				 * This doesn't actually work on all "VGA"
				 * controllers (it seems like setting MM=01
				 * and COE=1 isn't necessarily a good idea)
				 */
				vga_vram_base = 0xa0000;
				vga_vram_size = 0x10000;
				outb_p(6, VGA_GFX_I);
				outb_p(6, VGA_GFX_D);
#endif
				/*
				 * Normalise the palette registers, to point
				 * the 16 screen colours to the first 16
				 * DAC entries.
				 */

				for (i = 0; i < 16; i++) {
					inb_p(VGA_IS1_RC);
					outb_p(i, VGA_ATT_W);
					outb_p(i, VGA_ATT_W);
				}
				outb_p(0x20, VGA_ATT_W);

				/*
				 * Now set the DAC registers back to their
				 * default values
				 */
				for (i = 0; i < 16; i++) {
					outb_p(color_table[i], VGA_PEL_IW);
					outb_p(default_red[i], VGA_PEL_D);
					outb_p(default_grn[i], VGA_PEL_D);
					outb_p(default_blu[i], VGA_PEL_D);
				}
			}
		} else {
			static struct resource cga_console_resource =
			    { .name = "cga", .start = 0x3D4, .end = 0x3D5 };
			vga_video_type = VIDEO_TYPE_CGA;
			vga_vram_size = 0x2000;
			display_desc = "*CGA";
			request_resource(&ioport_resource,
					 &cga_console_resource);
			vga_video_font_height = 8;
		}
	}

	vga_vram_base = VGA_MAP_MEM(vga_vram_base, vga_vram_size);
	vga_vram_end = vga_vram_base + vga_vram_size;

	/*
	 *      Find out if there is a graphics card present.
	 *      Are there smarter methods around?
	 */
	p = (volatile u16 *) vga_vram_base;
	saved1 = scr_readw(p);
	saved2 = scr_readw(p + 1);
	scr_writew(0xAA55, p);
	scr_writew(0x55AA, p + 1);
	if (scr_readw(p) != 0xAA55 || scr_readw(p + 1) != 0x55AA) {
		scr_writew(saved1, p);
		scr_writew(saved2, p + 1);
		goto no_vga;
	}
	scr_writew(0x55AA, p);
	scr_writew(0xAA55, p + 1);
	if (scr_readw(p) != 0x55AA || scr_readw(p + 1) != 0xAA55) {
		scr_writew(saved1, p);
		scr_writew(saved2, p + 1);
		goto no_vga;
	}
	scr_writew(saved1, p);
	scr_writew(saved2, p + 1);

	if (vga_video_type == VIDEO_TYPE_EGAC
	    || vga_video_type == VIDEO_TYPE_VGAC
	    || vga_video_type == VIDEO_TYPE_EGAM) {
		vga_hardscroll_enabled = vga_hardscroll_user_enable;
		vga_default_font_height = screen_info.orig_video_points;
		vga_video_font_height = screen_info.orig_video_points;
		/* This may be suboptimal but is a safe bet - go with it */
		vga_scan_lines =
		    vga_video_font_height * vga_video_num_lines;
	}

	vgacon_xres = screen_info.orig_video_cols * VGA_FONTWIDTH;
	vgacon_yres = vga_scan_lines;

	if (!vga_init_done) {
		vgacon_scrollback_startup();
		vga_init_done = 1;
	}

	return display_desc;
}

static void vgacon_init(struct vc_data *c, int init)
{
	unsigned long p;

	/*
	 * We cannot be loaded as a module, therefore init is always 1,
	 * but vgacon_init can be called more than once, and init will
	 * not be 1.
	 */
	c->vc_can_do_color = vga_can_do_color;

	/* set dimensions manually if init != 0 since vc_resize() will fail */
	if (init) {
		c->vc_cols = vga_video_num_columns;
		c->vc_rows = vga_video_num_lines;
	} else
		vc_resize(c, vga_video_num_columns, vga_video_num_lines);

	c->vc_scan_lines = vga_scan_lines;
	c->vc_font.height = vga_video_font_height;
	c->vc_complement_mask = 0x7700;
	if (vga_512_chars)
		c->vc_hi_font_mask = 0x0800;
	p = *c->vc_uni_pagedir_loc;
	if (c->vc_uni_pagedir_loc == &c->vc_uni_pagedir ||
	    !--c->vc_uni_pagedir_loc[1])
		con_free_unimap(c);
	c->vc_uni_pagedir_loc = vgacon_uni_pagedir;
	vgacon_uni_pagedir[1]++;
	if (!vgacon_uni_pagedir[0] && p)
		con_set_default_unimap(c);
}

static void vgacon_deinit(struct vc_data *c)
{
	/* When closing the last console, reset video origin */
	if (!--vgacon_uni_pagedir[1]) {
		c->vc_visible_origin = vga_vram_base;
		vga_set_mem_top(c);
		con_free_unimap(c);
	}
	c->vc_uni_pagedir_loc = &c->vc_uni_pagedir;
	con_set_default_unimap(c);
}

static u8 vgacon_build_attr(struct vc_data *c, u8 color, u8 intensity,
			    u8 blink, u8 underline, u8 reverse, u8 italic)
{
	u8 attr = color;

	if (vga_can_do_color) {
		if (italic)
			attr = (attr & 0xF0) | c->vc_itcolor;
		else if (underline)
			attr = (attr & 0xf0) | c->vc_ulcolor;
		else if (intensity == 0)
			attr = (attr & 0xf0) | c->vc_halfcolor;
	}
	if (reverse)
		attr =
		    ((attr) & 0x88) | ((((attr) >> 4) | ((attr) << 4)) &
				       0x77);
	if (blink)
		attr ^= 0x80;
	if (intensity == 2)
		attr ^= 0x08;
	if (!vga_can_do_color) {
		if (italic)
			attr = (attr & 0xF8) | 0x02;
		else if (underline)
			attr = (attr & 0xf8) | 0x01;
		else if (intensity == 0)
			attr = (attr & 0xf0) | 0x08;
	}
	return attr;
}

static void vgacon_invert_region(struct vc_data *c, u16 * p, int count)
{
	int col = vga_can_do_color;

	while (count--) {
		u16 a = scr_readw(p);
		if (col)
			a = ((a) & 0x88ff) | (((a) & 0x7000) >> 4) |
			    (((a) & 0x0700) << 4);
		else
			a ^= ((a & 0x0700) == 0x0100) ? 0x7000 : 0x7700;
		scr_writew(a, p++);
	}
}

static void vgacon_set_cursor_size(int xpos, int from, int to)
{
	unsigned long flags;
	int curs, cure;

#ifdef TRIDENT_GLITCH
	if (xpos < 16)
		from--, to--;
#endif

	if ((from == cursor_size_lastfrom) && (to == cursor_size_lastto))
		return;
	cursor_size_lastfrom = from;
	cursor_size_lastto = to;

	spin_lock_irqsave(&vga_lock, flags);
	if (vga_video_type >= VIDEO_TYPE_VGAC) {
		outb_p(VGA_CRTC_CURSOR_START, vga_video_port_reg);
		curs = inb_p(vga_video_port_val);
		outb_p(VGA_CRTC_CURSOR_END, vga_video_port_reg);
		cure = inb_p(vga_video_port_val);
	} else {
		curs = 0;
		cure = 0;
	}

	curs = (curs & 0xc0) | from;
	cure = (cure & 0xe0) | to;

	outb_p(VGA_CRTC_CURSOR_START, vga_video_port_reg);
	outb_p(curs, vga_video_port_val);
	outb_p(VGA_CRTC_CURSOR_END, vga_video_port_reg);
	outb_p(cure, vga_video_port_val);
	spin_unlock_irqrestore(&vga_lock, flags);
}

static void vgacon_cursor(struct vc_data *c, int mode)
{
	if (c->vc_mode != KD_TEXT)
		return;

	vgacon_restore_screen(c);

	switch (mode) {
	case CM_ERASE:
		write_vga(14, (c->vc_pos - vga_vram_base) / 2);
	        if (vga_video_type >= VIDEO_TYPE_VGAC)
			vgacon_set_cursor_size(c->vc_x, 31, 30);
		else
			vgacon_set_cursor_size(c->vc_x, 31, 31);
		break;

	case CM_MOVE:
	case CM_DRAW:
		write_vga(14, (c->vc_pos - vga_vram_base) / 2);
		switch (c->vc_cursor_type & 0x0f) {
		case CUR_UNDERLINE:
			vgacon_set_cursor_size(c->vc_x,
					       c->vc_font.height -
					       (c->vc_font.height <
						10 ? 2 : 3),
					       c->vc_font.height -
					       (c->vc_font.height <
						10 ? 1 : 2));
			break;
		case CUR_TWO_THIRDS:
			vgacon_set_cursor_size(c->vc_x,
					       c->vc_font.height / 3,
					       c->vc_font.height -
					       (c->vc_font.height <
						10 ? 1 : 2));
			break;
		case CUR_LOWER_THIRD:
			vgacon_set_cursor_size(c->vc_x,
					       (c->vc_font.height * 2) / 3,
					       c->vc_font.height -
					       (c->vc_font.height <
						10 ? 1 : 2));
			break;
		case CUR_LOWER_HALF:
			vgacon_set_cursor_size(c->vc_x,
					       c->vc_font.height / 2,
					       c->vc_font.height -
					       (c->vc_font.height <
						10 ? 1 : 2));
			break;
		case CUR_NONE:
			if (vga_video_type >= VIDEO_TYPE_VGAC)
				vgacon_set_cursor_size(c->vc_x, 31, 30);
			else
				vgacon_set_cursor_size(c->vc_x, 31, 31);
			break;
		default:
			vgacon_set_cursor_size(c->vc_x, 1,
					       c->vc_font.height);
			break;
		}
		break;
	}
}

static int vgacon_doresize(struct vc_data *c,
		unsigned int width, unsigned int height)
{
	unsigned long flags;
	unsigned int scanlines = height * c->vc_font.height;
	u8 scanlines_lo = 0, r7 = 0, vsync_end = 0, mode, max_scan;

	spin_lock_irqsave(&vga_lock, flags);

	vgacon_xres = width * VGA_FONTWIDTH;
	vgacon_yres = height * c->vc_font.height;
	if (vga_video_type >= VIDEO_TYPE_VGAC) {
		outb_p(VGA_CRTC_MAX_SCAN, vga_video_port_reg);
		max_scan = inb_p(vga_video_port_val);

		if (max_scan & 0x80)
			scanlines <<= 1;

		outb_p(VGA_CRTC_MODE, vga_video_port_reg);
		mode = inb_p(vga_video_port_val);

		if (mode & 0x04)
			scanlines >>= 1;

		scanlines -= 1;
		scanlines_lo = scanlines & 0xff;

		outb_p(VGA_CRTC_OVERFLOW, vga_video_port_reg);
		r7 = inb_p(vga_video_port_val) & ~0x42;

		if (scanlines & 0x100)
			r7 |= 0x02;
		if (scanlines & 0x200)
			r7 |= 0x40;

		/* deprotect registers */
		outb_p(VGA_CRTC_V_SYNC_END, vga_video_port_reg);
		vsync_end = inb_p(vga_video_port_val);
		outb_p(VGA_CRTC_V_SYNC_END, vga_video_port_reg);
		outb_p(vsync_end & ~0x80, vga_video_port_val);
	}

	outb_p(VGA_CRTC_H_DISP, vga_video_port_reg);
	outb_p(width - 1, vga_video_port_val);
	outb_p(VGA_CRTC_OFFSET, vga_video_port_reg);
	outb_p(width >> 1, vga_video_port_val);

	if (vga_video_type >= VIDEO_TYPE_VGAC) {
		outb_p(VGA_CRTC_V_DISP_END, vga_video_port_reg);
		outb_p(scanlines_lo, vga_video_port_val);
		outb_p(VGA_CRTC_OVERFLOW, vga_video_port_reg);
		outb_p(r7,vga_video_port_val);

		/* reprotect registers */
		outb_p(VGA_CRTC_V_SYNC_END, vga_video_port_reg);
		outb_p(vsync_end, vga_video_port_val);
	}

	spin_unlock_irqrestore(&vga_lock, flags);
	return 0;
}

static int vgacon_switch(struct vc_data *c)
{
	int x = c->vc_cols * VGA_FONTWIDTH;
	int y = c->vc_rows * c->vc_font.height;
	int rows = screen_info.orig_video_lines * vga_default_font_height/
		c->vc_font.height;
	/*
	 * We need to save screen size here as it's the only way
	 * we can spot the screen has been resized and we need to
	 * set size of freshly allocated screens ourselves.
	 */
	vga_video_num_columns = c->vc_cols;
	vga_video_num_lines = c->vc_rows;

	/* We can only copy out the size of the video buffer here,
	 * otherwise we get into VGA BIOS */

	if (!vga_is_gfx) {
		scr_memcpyw((u16 *) c->vc_origin, (u16 *) c->vc_screenbuf,
			    c->vc_screenbuf_size > vga_vram_size ?
				vga_vram_size : c->vc_screenbuf_size);

		if ((vgacon_xres != x || vgacon_yres != y) &&
		    (!(vga_video_num_columns % 2) &&
		     vga_video_num_columns <= screen_info.orig_video_cols &&
		     vga_video_num_lines <= rows))
			vgacon_doresize(c, c->vc_cols, c->vc_rows);
	}

	vgacon_scrollback_init(c->vc_size_row);
	return 0;		/* Redrawing not needed */
}

static void vga_set_palette(struct vc_data *vc, unsigned char *table)
{
	int i, j;

	vga_w(state.vgabase, VGA_PEL_MSK, 0xff);
	for (i = j = 0; i < 16; i++) {
		vga_w(state.vgabase, VGA_PEL_IW, table[i]);
		vga_w(state.vgabase, VGA_PEL_D, vc->vc_palette[j++] >> 2);
		vga_w(state.vgabase, VGA_PEL_D, vc->vc_palette[j++] >> 2);
		vga_w(state.vgabase, VGA_PEL_D, vc->vc_palette[j++] >> 2);
	}
}

static int vgacon_set_palette(struct vc_data *vc, unsigned char *table)
{
#ifdef CAN_LOAD_PALETTE
	if (vga_video_type != VIDEO_TYPE_VGAC || vga_palette_blanked
	    || !CON_IS_VISIBLE(vc))
		return -EINVAL;
	vga_set_palette(vc, table);
	return 0;
#else
	return -EINVAL;
#endif
}

/* structure holding original VGA register settings */
static struct {
	unsigned char SeqCtrlIndex;	/* Sequencer Index reg.   */
	unsigned char CrtCtrlIndex;	/* CRT-Contr. Index reg.  */
	unsigned char CrtMiscIO;	/* Miscellaneous register */
	unsigned char HorizontalTotal;	/* CRT-Controller:00h */
	unsigned char HorizDisplayEnd;	/* CRT-Controller:01h */
	unsigned char StartHorizRetrace;	/* CRT-Controller:04h */
	unsigned char EndHorizRetrace;	/* CRT-Controller:05h */
	unsigned char Overflow;	/* CRT-Controller:07h */
	unsigned char StartVertRetrace;	/* CRT-Controller:10h */
	unsigned char EndVertRetrace;	/* CRT-Controller:11h */
	unsigned char ModeControl;	/* CRT-Controller:17h */
	unsigned char ClockingMode;	/* Seq-Controller:01h */
} vga_state;

static void vga_vesa_blank(struct vgastate *state, int mode)
{
	/* save original values of VGA controller registers */
	if (!vga_vesa_blanked) {
		spin_lock_irq(&vga_lock);
		vga_state.SeqCtrlIndex = vga_r(state->vgabase, VGA_SEQ_I);
		vga_state.CrtCtrlIndex = inb_p(vga_video_port_reg);
		vga_state.CrtMiscIO = vga_r(state->vgabase, VGA_MIS_R);
		spin_unlock_irq(&vga_lock);

		outb_p(0x00, vga_video_port_reg);	/* HorizontalTotal */
		vga_state.HorizontalTotal = inb_p(vga_video_port_val);
		outb_p(0x01, vga_video_port_reg);	/* HorizDisplayEnd */
		vga_state.HorizDisplayEnd = inb_p(vga_video_port_val);
		outb_p(0x04, vga_video_port_reg);	/* StartHorizRetrace */
		vga_state.StartHorizRetrace = inb_p(vga_video_port_val);
		outb_p(0x05, vga_video_port_reg);	/* EndHorizRetrace */
		vga_state.EndHorizRetrace = inb_p(vga_video_port_val);
		outb_p(0x07, vga_video_port_reg);	/* Overflow */
		vga_state.Overflow = inb_p(vga_video_port_val);
		outb_p(0x10, vga_video_port_reg);	/* StartVertRetrace */
		vga_state.StartVertRetrace = inb_p(vga_video_port_val);
		outb_p(0x11, vga_video_port_reg);	/* EndVertRetrace */
		vga_state.EndVertRetrace = inb_p(vga_video_port_val);
		outb_p(0x17, vga_video_port_reg);	/* ModeControl */
		vga_state.ModeControl = inb_p(vga_video_port_val);
		vga_state.ClockingMode = vga_rseq(state->vgabase, VGA_SEQ_CLOCK_MODE);
	}

	/* assure that video is enabled */
	/* "0x20" is VIDEO_ENABLE_bit in register 01 of sequencer */
	spin_lock_irq(&vga_lock);
	vga_wseq(state->vgabase, VGA_SEQ_CLOCK_MODE, vga_state.ClockingMode | 0x20);

	/* test for vertical retrace in process.... */
	if ((vga_state.CrtMiscIO & 0x80) == 0x80)
		vga_w(state->vgabase, VGA_MIS_W, vga_state.CrtMiscIO & 0xEF);

	/*
	 * Set <End of vertical retrace> to minimum (0) and
	 * <Start of vertical Retrace> to maximum (incl. overflow)
	 * Result: turn off vertical sync (VSync) pulse.
	 */
	if (mode & VESA_VSYNC_SUSPEND) {
		outb_p(0x10, vga_video_port_reg);	/* StartVertRetrace */
		outb_p(0xff, vga_video_port_val);	/* maximum value */
		outb_p(0x11, vga_video_port_reg);	/* EndVertRetrace */
		outb_p(0x40, vga_video_port_val);	/* minimum (bits 0..3)  */
		outb_p(0x07, vga_video_port_reg);	/* Overflow */
		outb_p(vga_state.Overflow | 0x84, vga_video_port_val);	/* bits 9,10 of vert. retrace */
	}

	if (mode & VESA_HSYNC_SUSPEND) {
		/*
		 * Set <End of horizontal retrace> to minimum (0) and
		 *  <Start of horizontal Retrace> to maximum
		 * Result: turn off horizontal sync (HSync) pulse.
		 */
		outb_p(0x04, vga_video_port_reg);	/* StartHorizRetrace */
		outb_p(0xff, vga_video_port_val);	/* maximum */
		outb_p(0x05, vga_video_port_reg);	/* EndHorizRetrace */
		outb_p(0x00, vga_video_port_val);	/* minimum (0) */
	}

	/* restore both index registers */
	vga_w(state->vgabase, VGA_SEQ_I, vga_state.SeqCtrlIndex);
	outb_p(vga_state.CrtCtrlIndex, vga_video_port_reg);
	spin_unlock_irq(&vga_lock);
}

static void vga_vesa_unblank(struct vgastate *state)
{
	/* restore original values of VGA controller registers */
	spin_lock_irq(&vga_lock);
	vga_w(state->vgabase, VGA_MIS_W, vga_state.CrtMiscIO);

	outb_p(0x00, vga_video_port_reg);	/* HorizontalTotal */
	outb_p(vga_state.HorizontalTotal, vga_video_port_val);
	outb_p(0x01, vga_video_port_reg);	/* HorizDisplayEnd */
	outb_p(vga_state.HorizDisplayEnd, vga_video_port_val);
	outb_p(0x04, vga_video_port_reg);	/* StartHorizRetrace */
	outb_p(vga_state.StartHorizRetrace, vga_video_port_val);
	outb_p(0x05, vga_video_port_reg);	/* EndHorizRetrace */
	outb_p(vga_state.EndHorizRetrace, vga_video_port_val);
	outb_p(0x07, vga_video_port_reg);	/* Overflow */
	outb_p(vga_state.Overflow, vga_video_port_val);
	outb_p(0x10, vga_video_port_reg);	/* StartVertRetrace */
	outb_p(vga_state.StartVertRetrace, vga_video_port_val);
	outb_p(0x11, vga_video_port_reg);	/* EndVertRetrace */
	outb_p(vga_state.EndVertRetrace, vga_video_port_val);
	outb_p(0x17, vga_video_port_reg);	/* ModeControl */
	outb_p(vga_state.ModeControl, vga_video_port_val);
	/* ClockingMode */
	vga_wseq(state->vgabase, VGA_SEQ_CLOCK_MODE, vga_state.ClockingMode);

	/* restore index/control registers */
	vga_w(state->vgabase, VGA_SEQ_I, vga_state.SeqCtrlIndex);
	outb_p(vga_state.CrtCtrlIndex, vga_video_port_reg);
	spin_unlock_irq(&vga_lock);
}

static void vga_pal_blank(struct vgastate *state)
{
	int i;

	vga_w(state->vgabase, VGA_PEL_MSK, 0xff);
	for (i = 0; i < 16; i++) {
		vga_w(state->vgabase, VGA_PEL_IW, i);
		vga_w(state->vgabase, VGA_PEL_D, 0);
		vga_w(state->vgabase, VGA_PEL_D, 0);
		vga_w(state->vgabase, VGA_PEL_D, 0);
	}
}

static int vgacon_blank(struct vc_data *c, int blank, int mode_switch)
{
	switch (blank) {
	case 0:		/* Unblank */
		if (vga_vesa_blanked) {
			vga_vesa_unblank(&state);
			vga_vesa_blanked = 0;
		}
		if (vga_palette_blanked) {
			vga_set_palette(c, color_table);
			vga_palette_blanked = 0;
			return 0;
		}
		vga_is_gfx = 0;
		/* Tell console.c that it has to restore the screen itself */
		return 1;
	case 1:		/* Normal blanking */
	case -1:	/* Obsolete */
		if (!mode_switch && vga_video_type == VIDEO_TYPE_VGAC) {
			vga_pal_blank(&state);
			vga_palette_blanked = 1;
			return 0;
		}
		vgacon_set_origin(c);
		scr_memsetw((void *) vga_vram_base, BLANK,
			    c->vc_screenbuf_size);
		if (mode_switch)
			vga_is_gfx = 1;
		return 1;
	default:		/* VESA blanking */
		if (vga_video_type == VIDEO_TYPE_VGAC) {
			vga_vesa_blank(&state, blank - 1);
			vga_vesa_blanked = blank;
		}
		return 0;
	}
}

/*
 * PIO_FONT support.
 *
 * The font loading code goes back to the codepage package by
 * Joel Hoffman (joel@wam.umd.edu). (He reports that the original
 * reference is: "From: p. 307 of _Programmer's Guide to PC & PS/2
 * Video Systems_ by Richard Wilton. 1987.  Microsoft Press".)
 *
 * Change for certain monochrome monitors by Yury Shevchuck
 * (sizif@botik.yaroslavl.su).
 */

#ifdef CAN_LOAD_EGA_FONTS

#define colourmap 0xa0000
/* Pauline Middelink <middelin@polyware.iaf.nl> reports that we
   should use 0xA0000 for the bwmap as well.. */
#define blackwmap 0xa0000
#define cmapsz 8192

static int vgacon_do_font_op(struct vgastate *state,char *arg,int set,int ch512)
{
	unsigned short video_port_status = vga_video_port_reg + 6;
	int font_select = 0x00, beg, i;
	char *charmap;
	
	if (vga_video_type != VIDEO_TYPE_EGAM) {
		charmap = (char *) VGA_MAP_MEM(colourmap, 0);
		beg = 0x0e;
#ifdef VGA_CAN_DO_64KB
		if (vga_video_type == VIDEO_TYPE_VGAC)
			beg = 0x06;
#endif
	} else {
		charmap = (char *) VGA_MAP_MEM(blackwmap, 0);
		beg = 0x0a;
	}

#ifdef BROKEN_GRAPHICS_PROGRAMS
	/*
	 * All fonts are loaded in slot 0 (0:1 for 512 ch)
	 */

	if (!arg)
		return -EINVAL;	/* Return to default font not supported */

	vga_font_is_default = 0;
	font_select = ch512 ? 0x04 : 0x00;
#else
	/*
	 * The default font is kept in slot 0 and is never touched.
	 * A custom font is loaded in slot 2 (256 ch) or 2:3 (512 ch)
	 */

	if (set) {
		vga_font_is_default = !arg;
		if (!arg)
			ch512 = 0;	/* Default font is always 256 */
		font_select = arg ? (ch512 ? 0x0e : 0x0a) : 0x00;
	}

	if (!vga_font_is_default)
		charmap += 4 * cmapsz;
#endif

	unlock_kernel();
	spin_lock_irq(&vga_lock);
	/* First, the Sequencer */
	vga_wseq(state->vgabase, VGA_SEQ_RESET, 0x1);
	/* CPU writes only to map 2 */
	vga_wseq(state->vgabase, VGA_SEQ_PLANE_WRITE, 0x04);	
	/* Sequential addressing */
	vga_wseq(state->vgabase, VGA_SEQ_MEMORY_MODE, 0x07);	
	/* Clear synchronous reset */
	vga_wseq(state->vgabase, VGA_SEQ_RESET, 0x03);

	/* Now, the graphics controller, select map 2 */
	vga_wgfx(state->vgabase, VGA_GFX_PLANE_READ, 0x02);		
	/* disable odd-even addressing */
	vga_wgfx(state->vgabase, VGA_GFX_MODE, 0x00);
	/* map start at A000:0000 */
	vga_wgfx(state->vgabase, VGA_GFX_MISC, 0x00);
	spin_unlock_irq(&vga_lock);

	if (arg) {
		if (set)
			for (i = 0; i < cmapsz; i++)
				vga_writeb(arg[i], charmap + i);
		else
			for (i = 0; i < cmapsz; i++)
				arg[i] = vga_readb(charmap + i);

		/*
		 * In 512-character mode, the character map is not contiguous if
		 * we want to remain EGA compatible -- which we do
		 */

		if (ch512) {
			charmap += 2 * cmapsz;
			arg += cmapsz;
			if (set)
				for (i = 0; i < cmapsz; i++)
					vga_writeb(arg[i], charmap + i);
			else
				for (i = 0; i < cmapsz; i++)
					arg[i] = vga_readb(charmap + i);
		}
	}

	spin_lock_irq(&vga_lock);
	/* First, the sequencer, Synchronous reset */
	vga_wseq(state->vgabase, VGA_SEQ_RESET, 0x01);	
	/* CPU writes to maps 0 and 1 */
	vga_wseq(state->vgabase, VGA_SEQ_PLANE_WRITE, 0x03);
	/* odd-even addressing */
	vga_wseq(state->vgabase, VGA_SEQ_MEMORY_MODE, 0x03);
	/* Character Map Select */
	if (set)
		vga_wseq(state->vgabase, VGA_SEQ_CHARACTER_MAP, font_select);
	/* clear synchronous reset */
	vga_wseq(state->vgabase, VGA_SEQ_RESET, 0x03);

	/* Now, the graphics controller, select map 0 for CPU */
	vga_wgfx(state->vgabase, VGA_GFX_PLANE_READ, 0x00);
	/* enable even-odd addressing */
	vga_wgfx(state->vgabase, VGA_GFX_MODE, 0x10);
	/* map starts at b800:0 or b000:0 */
	vga_wgfx(state->vgabase, VGA_GFX_MISC, beg);

	/* if 512 char mode is already enabled don't re-enable it. */
	if ((set) && (ch512 != vga_512_chars)) {
		int i;	
		
		/* attribute controller */
		for (i = 0; i < MAX_NR_CONSOLES; i++) {
			struct vc_data *c = vc_cons[i].d;
			if (c && c->vc_sw == &vga_con)
				c->vc_hi_font_mask = ch512 ? 0x0800 : 0;
		}
		vga_512_chars = ch512;
		/* 256-char: enable intensity bit
		   512-char: disable intensity bit */
		inb_p(video_port_status);	/* clear address flip-flop */
		/* color plane enable register */
		vga_wattr(state->vgabase, VGA_ATC_PLANE_ENABLE, ch512 ? 0x07 : 0x0f);
		/* Wilton (1987) mentions the following; I don't know what
		   it means, but it works, and it appears necessary */
		inb_p(video_port_status);
		vga_wattr(state->vgabase, VGA_AR_ENABLE_DISPLAY, 0);	
	}
	spin_unlock_irq(&vga_lock);
	lock_kernel();
	return 0;
}

/*
 * Adjust the screen to fit a font of a certain height
 */
static int vgacon_adjust_height(struct vc_data *vc, unsigned fontheight)
{
	unsigned char ovr, vde, fsr;
	int rows, maxscan, i;

	rows = vc->vc_scan_lines / fontheight;	/* Number of video rows we end up with */
	maxscan = rows * fontheight - 1;	/* Scan lines to actually display-1 */

	/* Reprogram the CRTC for the new font size
	   Note: the attempt to read the overflow register will fail
	   on an EGA, but using 0xff for the previous value appears to
	   be OK for EGA text modes in the range 257-512 scan lines, so I
	   guess we don't need to worry about it.

	   The same applies for the spill bits in the font size and cursor
	   registers; they are write-only on EGA, but it appears that they
	   are all don't care bits on EGA, so I guess it doesn't matter. */

	spin_lock_irq(&vga_lock);
	outb_p(0x07, vga_video_port_reg);	/* CRTC overflow register */
	ovr = inb_p(vga_video_port_val);
	outb_p(0x09, vga_video_port_reg);	/* Font size register */
	fsr = inb_p(vga_video_port_val);
	spin_unlock_irq(&vga_lock);

	vde = maxscan & 0xff;	/* Vertical display end reg */
	ovr = (ovr & 0xbd) +	/* Overflow register */
	    ((maxscan & 0x100) >> 7) + ((maxscan & 0x200) >> 3);
	fsr = (fsr & 0xe0) + (fontheight - 1);	/*  Font size register */

	spin_lock_irq(&vga_lock);
	outb_p(0x07, vga_video_port_reg);	/* CRTC overflow register */
	outb_p(ovr, vga_video_port_val);
	outb_p(0x09, vga_video_port_reg);	/* Font size */
	outb_p(fsr, vga_video_port_val);
	outb_p(0x12, vga_video_port_reg);	/* Vertical display limit */
	outb_p(vde, vga_video_port_val);
	spin_unlock_irq(&vga_lock);
	vga_video_font_height = fontheight;

	for (i = 0; i < MAX_NR_CONSOLES; i++) {
		struct vc_data *c = vc_cons[i].d;

		if (c && c->vc_sw == &vga_con) {
			if (CON_IS_VISIBLE(c)) {
			        /* void size to cause regs to be rewritten */
				cursor_size_lastfrom = 0;
				cursor_size_lastto = 0;
				c->vc_sw->con_cursor(c, CM_DRAW);
			}
			c->vc_font.height = fontheight;
			vc_resize(c, 0, rows);	/* Adjust console size */
		}
	}
	return 0;
}

static int vgacon_font_set(struct vc_data *c, struct console_font *font, unsigned flags)
{
	unsigned charcount = font->charcount;
	int rc;

	if (vga_video_type < VIDEO_TYPE_EGAM)
		return -EINVAL;

	if (font->width != VGA_FONTWIDTH ||
	    (charcount != 256 && charcount != 512))
		return -EINVAL;

	rc = vgacon_do_font_op(&state, font->data, 1, charcount == 512);
	if (rc)
		return rc;

	if (!(flags & KD_FONT_FLAG_DONT_RECALC))
		rc = vgacon_adjust_height(c, font->height);
	return rc;
}

static int vgacon_font_get(struct vc_data *c, struct console_font *font)
{
	if (vga_video_type < VIDEO_TYPE_EGAM)
		return -EINVAL;

	font->width = VGA_FONTWIDTH;
	font->height = c->vc_font.height;
	font->charcount = vga_512_chars ? 512 : 256;
	if (!font->data)
		return 0;
	return vgacon_do_font_op(&state, font->data, 0, 0);
}

#else

#define vgacon_font_set NULL
#define vgacon_font_get NULL

#endif

static int vgacon_resize(struct vc_data *c, unsigned int width,
			 unsigned int height, unsigned int user)
{
	if (width % 2 || width > screen_info.orig_video_cols ||
	    height > (screen_info.orig_video_lines * vga_default_font_height)/
	    c->vc_font.height)
		/* let svgatextmode tinker with video timings and
		   return success */
		return (user) ? 0 : -EINVAL;

	if (CON_IS_VISIBLE(c) && !vga_is_gfx) /* who knows */
		vgacon_doresize(c, width, height);
	return 0;
}

static int vgacon_set_origin(struct vc_data *c)
{
	if (vga_is_gfx ||	/* We don't play origin tricks in graphic modes */
	    (console_blanked && !vga_palette_blanked))	/* Nor we write to blanked screens */
		return 0;
	c->vc_origin = c->vc_visible_origin = vga_vram_base;
	vga_set_mem_top(c);
	vga_rolled_over = 0;
	return 1;
}

static void vgacon_save_screen(struct vc_data *c)
{
	static int vga_bootup_console = 0;

	if (!vga_bootup_console) {
		/* This is a gross hack, but here is the only place we can
		 * set bootup console parameters without messing up generic
		 * console initialization routines.
		 */
		vga_bootup_console = 1;
		c->vc_x = screen_info.orig_x;
		c->vc_y = screen_info.orig_y;
	}

	/* We can't copy in more then the size of the video buffer,
	 * or we'll be copying in VGA BIOS */

	if (!vga_is_gfx)
		scr_memcpyw((u16 *) c->vc_screenbuf, (u16 *) c->vc_origin,
			    c->vc_screenbuf_size > vga_vram_size ? vga_vram_size : c->vc_screenbuf_size);
}

static int vgacon_scroll(struct vc_data *c, int t, int b, int dir,
			 int lines)
{
	unsigned long oldo;
	unsigned int delta;

	if (t || b != c->vc_rows || vga_is_gfx || c->vc_mode != KD_TEXT)
		return 0;

	if (!vga_hardscroll_enabled || lines >= c->vc_rows / 2)
		return 0;

	vgacon_restore_screen(c);
	oldo = c->vc_origin;
	delta = lines * c->vc_size_row;
	if (dir == SM_UP) {
		vgacon_scrollback_update(c, t, lines);
		if (c->vc_scr_end + delta >= vga_vram_end) {
			scr_memcpyw((u16 *) vga_vram_base,
				    (u16 *) (oldo + delta),
				    c->vc_screenbuf_size - delta);
			c->vc_origin = vga_vram_base;
			vga_rolled_over = oldo - vga_vram_base;
		} else
			c->vc_origin += delta;
		scr_memsetw((u16 *) (c->vc_origin + c->vc_screenbuf_size -
				     delta), c->vc_video_erase_char,
			    delta);
	} else {
		if (oldo - delta < vga_vram_base) {
			scr_memmovew((u16 *) (vga_vram_end -
					      c->vc_screenbuf_size +
					      delta), (u16 *) oldo,
				     c->vc_screenbuf_size - delta);
			c->vc_origin = vga_vram_end - c->vc_screenbuf_size;
			vga_rolled_over = 0;
		} else
			c->vc_origin -= delta;
		c->vc_scr_end = c->vc_origin + c->vc_screenbuf_size;
		scr_memsetw((u16 *) (c->vc_origin), c->vc_video_erase_char,
			    delta);
	}
	c->vc_scr_end = c->vc_origin + c->vc_screenbuf_size;
	c->vc_visible_origin = c->vc_origin;
	vga_set_mem_top(c);
	c->vc_pos = (c->vc_pos - oldo) + c->vc_origin;
	return 1;
}


/*
 *  The console `switch' structure for the VGA based console
 */

static int vgacon_dummy(struct vc_data *c)
{
	return 0;
}

#define DUMMY (void *) vgacon_dummy

const struct consw vga_con = {
	.owner = THIS_MODULE,
	.con_startup = vgacon_startup,
	.con_init = vgacon_init,
	.con_deinit = vgacon_deinit,
	.con_clear = DUMMY,
	.con_putc = DUMMY,
	.con_putcs = DUMMY,
	.con_cursor = vgacon_cursor,
	.con_scroll = vgacon_scroll,
	.con_bmove = DUMMY,
	.con_switch = vgacon_switch,
	.con_blank = vgacon_blank,
	.con_font_set = vgacon_font_set,
	.con_font_get = vgacon_font_get,
	.con_resize = vgacon_resize,
	.con_set_palette = vgacon_set_palette,
	.con_scrolldelta = vgacon_scrolldelta,
	.con_set_origin = vgacon_set_origin,
	.con_save_screen = vgacon_save_screen,
	.con_build_attr = vgacon_build_attr,
	.con_invert_region = vgacon_invert_region,
};

MODULE_LICENSE("GPL");