Linux Audio

Check our new training course

Embedded Linux Audio

Check our new training course
with Creative Commons CC-BY-SA
lecture materials

Bootlin logo

Elixir Cross Referencer

Loading...
   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
1415
1416
1417
1418
1419
1420
1421
1422
1423
1424
1425
1426
1427
1428
1429
1430
1431
1432
1433
1434
1435
1436
1437
1438
1439
1440
1441
1442
1443
1444
1445
1446
1447
1448
1449
1450
1451
1452
1453
1454
1455
1456
1457
1458
1459
1460
1461
1462
1463
1464
1465
1466
1467
1468
1469
1470
1471
1472
1473
1474
1475
1476
1477
1478
1479
1480
1481
1482
1483
1484
1485
1486
1487
1488
1489
1490
1491
1492
1493
1494
1495
1496
1497
1498
1499
1500
1501
1502
1503
1504
1505
1506
1507
1508
1509
1510
1511
1512
1513
1514
1515
1516
1517
1518
1519
1520
1521
1522
1523
1524
1525
1526
1527
1528
1529
1530
1531
1532
1533
1534
1535
1536
1537
1538
1539
1540
1541
1542
1543
1544
1545
1546
1547
1548
1549
1550
1551
1552
1553
1554
1555
1556
1557
1558
1559
1560
1561
1562
1563
1564
1565
1566
1567
1568
1569
1570
1571
1572
1573
1574
1575
1576
1577
1578
1579
1580
1581
1582
1583
1584
1585
1586
1587
1588
1589
1590
1591
1592
1593
1594
1595
1596
1597
1598
1599
1600
1601
1602
1603
1604
1605
1606
1607
1608
1609
1610
1611
1612
1613
1614
1615
1616
1617
1618
1619
1620
1621
1622
1623
1624
1625
1626
1627
1628
1629
1630
1631
1632
1633
1634
1635
1636
1637
1638
1639
1640
1641
1642
1643
1644
1645
1646
1647
1648
1649
1650
1651
1652
1653
1654
1655
1656
1657
1658
1659
1660
1661
1662
1663
1664
1665
1666
1667
1668
1669
1670
1671
1672
1673
1674
1675
1676
1677
1678
1679
1680
1681
1682
1683
1684
1685
1686
1687
1688
1689
1690
1691
1692
1693
1694
1695
1696
1697
1698
1699
1700
1701
1702
1703
1704
1705
1706
1707
1708
1709
1710
1711
1712
1713
1714
1715
1716
1717
1718
1719
1720
1721
1722
1723
1724
1725
1726
1727
1728
1729
1730
1731
1732
1733
1734
1735
1736
1737
1738
1739
1740
1741
1742
1743
1744
1745
1746
1747
1748
1749
1750
1751
1752
1753
1754
1755
1756
1757
1758
1759
1760
1761
1762
1763
1764
1765
1766
1767
1768
1769
1770
1771
1772
1773
1774
1775
1776
1777
1778
1779
1780
1781
1782
1783
1784
1785
1786
1787
1788
1789
1790
1791
1792
1793
1794
1795
1796
1797
1798
1799
1800
1801
1802
1803
1804
1805
1806
1807
1808
1809
1810
1811
1812
1813
1814
1815
1816
1817
1818
1819
1820
1821
1822
1823
1824
1825
1826
1827
1828
1829
1830
1831
1832
1833
1834
1835
1836
1837
1838
1839
1840
1841
1842
!
!	Display adapter & video mode setup, version 2.11 (03-May-97)
!
!	Copyright (C) 1995 -- 1997 Martin Mares <mj@k332.feld.cvut.cz>
!	Based on the original setup.S code (C) Linus Torvalds and Mats Anderson
!

#include <linux/config.h> /* for CONFIG_VIDEO_* */

! Enable autodetection of SVGA adapters and modes. If you really need this
! feature, drop me a mail as I think of removing it some day...
#undef CONFIG_VIDEO_SVGA

! Enable autodetection of VESA modes
#define CONFIG_VIDEO_VESA

! Enable compacting of mode table
#define CONFIG_VIDEO_COMPACT

! Retain screen contents when switching modes
#define CONFIG_VIDEO_RETAIN

! Enable local mode list
#undef CONFIG_VIDEO_LOCAL

! Force 400 scan lines for standard modes (hack to fix bad behaviour
! of certain broken BIOS'es -- don't use unless needed)
#undef CONFIG_VIDEO_400_HACK

! A special hack allowing to force specific BIOS mode ID along with specific
! dimensions. Especially useful for certain X-Window graphics mode hacks
! (e.g., 800x600 modes on IBM ThinkPad).
#undef CONFIG_VIDEO_GFX_HACK
#define VIDEO_GFX_BIOS_AX 0x4f02	/* 800x600 on ThinkPad */
#define VIDEO_GFX_BIOS_BX 0x0102
#define VIDEO_GFX_DUMMY_RESOLUTION 0x6425	/* 100x37 */

! This code uses an extended set of video mode numbers. These include:
! Aliases for standard modes
!	NORMAL_VGA (-1)
!	EXTENDED_VGA (-2)
!	ASK_VGA (-3)
! Video modes numbered by menu position -- NOT RECOMMENDED because of lack
! of compatibility when extending the table. These are between 0x00 and 0xff.
#define VIDEO_FIRST_MENU 0x0000
! Standard BIOS video modes (BIOS number + 0x0100)
#define VIDEO_FIRST_BIOS 0x0100
! VESA BIOS video modes (VESA number + 0x0200)
#define VIDEO_FIRST_VESA 0x0200
! Video7 special modes (BIOS number + 0x0900)
#define VIDEO_FIRST_V7 0x0900
! Special video modes
#define VIDEO_FIRST_SPECIAL 0x0f00
#define VIDEO_80x25 0x0f00
#define VIDEO_8POINT 0x0f01
#define VIDEO_80x43 0x0f02
#define VIDEO_80x28 0x0f03
#define VIDEO_CURRENT_MODE 0x0f04
#define VIDEO_80x30 0x0f05
#define VIDEO_80x34 0x0f06
#define VIDEO_80x60 0x0f07
#define VIDEO_GFX_HACK 0x0f08
#define VIDEO_LAST_SPECIAL 0x0f09
! Video modes given by resolution
#define VIDEO_FIRST_RESOLUTION 0x1000

! The "recalculate timings" flag
#define VIDEO_RECALC 0x8000

! Positions of various video parameters passed to the kernel
#define PARAM_CURSOR_POS	0
#define PARAM_VIDEO_PAGE	4
#define PARAM_VIDEO_MODE	6
#define PARAM_VIDEO_COLS	7
#define PARAM_VIDEO_EGA_BX	10
#define PARAM_VIDEO_LINES	14
#define PARAM_HAVE_VGA		15
#define PARAM_FONT_POINTS	16

! Define DO_STORE according to CONFIG_VIDEO_RETAIN
#ifdef CONFIG_VIDEO_RETAIN
#define DO_STORE call store_screen
#else
#define DO_STORE
#endif /* CONFIG_VIDEO_RETAIN */

!
! This is the main entry point called by setup.S
!
! Input:
!	DS pointing to the bootsector

video:	push	ds		! We use different segments
	push	ds		! FS contains original DS
	pop	fs
	push	cs		! DS is equal to CS
	pop	ds
	push	cs		! ES is equal to CS
	pop	es
	xor	ax,ax
	mov	gs,ax		! GS is zero
	cld
	call	basic_detect	! Basic adapter type testing (EGA/VGA/MDA/CGA)
#ifdef CONFIG_VIDEO_SELECT
	seg	fs		! User-selected video mode
	mov	ax,[0x01fa]
	cmp	ax,#ASK_VGA	! Bring up the menu
	jz	vid2
	call	mode_set	! Set the mode
	jc	vid1
	lea	si,badmdt	! Invalid mode ID
	call	prtstr
vid2:	call	mode_menu
vid1:
#ifdef CONFIG_VIDEO_RETAIN
	call	restore_screen	! Restore screen contents
#endif /* CONFIG_VIDEO_RETAIN */
#endif /* CONFIG_VIDEO_SELECT */
	call	mode_params	! Store mode parameters
	pop	ds		! Restore original DS
	ret

!
! Detect if we have CGA, MDA, EGA or VGA and pass it to the kernel.
!

basic_detect:
	seg	fs		! Default is no VGA
	movb	[PARAM_HAVE_VGA],#0

	mov	ah,#0x12	! Check EGA/VGA
	mov	bl,#0x10
	int	0x10
	seg	fs
	mov	[PARAM_VIDEO_EGA_BX],bx	! Used for identification of EGA in the kernel
	cmp	bl,#0x10	! No, this is a CGA/MDA/HGA card.
	je	basret
	incb	[adapter]

	mov	ax,#0x1a00	! Check for EGA/VGA discrimination
	int	0x10
	cmp	al,#0x1a	! 1a means VGA, anything else EGA
	jne	basret
	seg	fs
	incb	[PARAM_HAVE_VGA]	! We've detected a VGA
	incb	[adapter]

basret:	ret

!
! Store the video mode parameters for later usage by the kernel.
! This is done by asking the BIOS except for the rows/columns
! parameters in the default 80x25 mode -- these are set directly,
! because some very obscure BIOSes supply insane values.
!

mode_params:
	mov	ah,#0x03	! Read cursor position
	xor	bh,bh
	int	0x10
	seg	fs
	mov	[PARAM_CURSOR_POS],dx

	mov	ah,#0x0f	! Read page/mode/width
	int	0x10
	seg	fs
	mov	[PARAM_VIDEO_PAGE],bx
	seg	fs
	mov	[PARAM_VIDEO_MODE],ax	! Video mode and screen width
	cmp	al,#7			! MDA/HGA => segment differs
	jnz	mopar0
	mov	[video_segment],#0xb000
mopar0:	seg	gs			! Font size
	mov	ax,[0x485]
	seg	fs
	mov	[PARAM_FONT_POINTS],ax	! (valid only on EGA/VGA)

	mov	ax,[force_size]	! Forced size?
	or	ax,ax
	jz	mopar1
	seg	fs
	mov	[PARAM_VIDEO_COLS],ah
	seg	fs
	mov	[PARAM_VIDEO_LINES],al
	ret

mopar1:	mov	al,#25
	cmpb	[adapter],#0	! If we are on CGA/MDA/HGA, the screen must
	jz	mopar2		! have 25 lines.
	seg	gs		! On EGA/VGA, use the EGA+ BIOS variable
	mov	al,[0x484]	! containing maximal line number.
	inc	al
mopar2:	seg	fs
	movb	[PARAM_VIDEO_LINES],al
	ret

#ifdef CONFIG_VIDEO_SELECT

!
! The video mode menu
!

mode_menu:
	lea	si,keymsg	! "Return/Space/Timeout" message
	call	prtstr
	call	flush
nokey:	call	getkt
	cmp	al,#0x0d	! ENTER ?
	je	listm		! yes - manual mode selection
	cmp	al,#0x20	! SPACE ?
	je	defmd1		! no - repeat
	call 	beep
	jmp	nokey
defmd1:	ret			! No mode selected => use the 80x25 default

listm:	call	mode_table	! We need a mode table to be listed
listm0:	lea	si,name_bann	! Print adapter name
	call	prtstr
	mov	si,[card_name]
	or	si,si
	jnz	an2
	mov	al,[adapter]
	lea	si,old_name
	or	al,al
	jz	an1
	lea	si,ega_name
	dec	al
	jz	an1
	lea	si,vga_name
	jmp	an1
an2:	call	prtstr
	lea	si,svga_name
an1:	call	prtstr
	lea	si,listhdr	! Table header
	call	prtstr
	mov	dl,#0x30	! DL holds mode number
	lea	si,modelist
lm1:	cmp	(si),#ASK_VGA	! End?
	jz	lm2
	mov	al,dl		! Menu selection number
	call	prtchr
	call	prtsp2
	lodsw
	call	prthw		! Mode ID
	call	prtsp2
	mov	al,(si+1)
	call	prtdec		! Rows
	mov	al,#0x78	! 'x'
	call	prtchr
	lodsw
	call	prtdec		! Columns
	mov	al,#0x0d	! New line
	call	prtchr
	mov	al,#0x0a
	call	prtchr
	inc	dl		! Next character
	cmp	dl,#0x3a
	jnz	lm1
	mov	dl,#0x61
	jmp	lm1

lm2:	lea	si,prompt	! Mode prompt
	call	prtstr
	lea	di,edit_buf	! Editor buffer
lm3:	call	getkey
	cmp	al,#0x0d	! Enter?
	jz	lment
	cmp	al,#0x08	! Backspace?
	jz	lmbs
	cmp	al,#0x20	! Printable?
	jc	lm3
	cmp	di,#edit_buf+4	! Enough space?
	jz	lm3
	stosb
	call	prtchr
	jmp	lm3

lmbs:	cmp	di,#edit_buf	! Backspace
	jz	lm3
	dec	di
	mov	al,#0x08
	call	prtchr
	call	prtspc
	mov	al,#0x08
	call	prtchr
	jmp	lm3

lment:	movb	(di),#0
	lea	si,crlft
	call	prtstr
	lea	si,edit_buf
	cmpb	(si),#0		! Empty string => use default mode
	jz	lmdef
	cmpb	(si+1),#0	! One character => menu selection
	jz	mnusel
	cmp	(si),#0x6373	! "scan" => mode scanning
	jnz	lmhx
	cmp	(si+2),#0x6e61
	jz	lmscan
lmhx:	xor	bx,bx		! Else => mode ID in hex
lmhex:	lodsb
	or	al,al
	jz	lmuse1
	sub	al,#0x30
	jc	lmbad
	cmp	al,#10
	jc	lmhx1
	sub	al,#7
	and	al,#0xdf
	cmp	al,#10
	jc	lmbad
	cmp	al,#16
	jnc	lmbad
lmhx1:	shl	bx,#4
	or	bl,al
	jmp	lmhex
lmuse1:	mov	ax,bx
	jmp	lmuse

mnusel:	lodsb			! Menu selection
	xor	ah,ah
	sub	al,#0x30
	jc	lmbad
	cmp	al,#10
	jc	lmuse
	cmp	al,#0x61-0x30
	jc	lmbad
	sub	al,#0x61-0x30-10
	cmp	al,#36
	jnc	lmbad
lmuse:	call	mode_set
	jc	lmdef
lmbad:	lea	si,unknt
	call	prtstr
	br	lm2

lmscan:	cmpb	[adapter],#0	! Scanning supported only on EGA/VGA
	jz	lmbad
	mov	[mt_end],#0	! Scanning of modes: done as new autodetection
	movb	[scanning],#1
	call	mode_table
	br	listm0

lmdef:	ret

!
! Additional parts of mode_set... (relative jumps, you know)
!

setv7:				! Video7 extended modes
	DO_STORE
	sub	bh,#VIDEO_FIRST_V7>>8
	mov	ax,#0x6f05
	int	0x10
	stc
	ret

_setrec:	br	setrec	! Ugly...

!
! Aliases for backward compatibility.
!

setalias:
	mov	ax,#VIDEO_80x25
	inc	bx
	jz	mode_set
	mov	al,#VIDEO_8POINT-VIDEO_FIRST_SPECIAL
	inc	bx
	jnz	setbad

	! Fall-thru !

!
! Setting of user mode (AX=mode ID) => CF=success
!

mode_set:
	mov	bx,ax
	cmp	ah,#0xff
	jz	setalias
	test	ah,#VIDEO_RECALC>>8
	jnz	_setrec
	cmp	ah,#VIDEO_FIRST_RESOLUTION>>8
	jnc	setres
	cmp	ah,#VIDEO_FIRST_SPECIAL>>8
	jz	setspc
	cmp	ah,#VIDEO_FIRST_V7>>8
	jz	setv7
	cmp	ah,#VIDEO_FIRST_VESA>>8
	jnc	setvesa
	or	ah,ah
	jz	setmenu
	dec	ah
	jz	setbios
setbad:	clc
	movb	[do_restore],#0	! The screen needn't be restored
	ret

setvesa:
	DO_STORE
	sub	bh,#VIDEO_FIRST_VESA>>8
	mov	ax,#0x4f02	! VESA BIOS mode set call
	int	0x10
	cmp	ax,#0x004f	! AL=4f if implemented, AH=0 if OK
	jnz	setbad
	stc
	ret

setbios:
	DO_STORE
	int	0x10		! Standard BIOS mode set call
	push	bx
	mov	ah,#0x0f	! Check if really set
	int	0x10
	pop	bx
	cmp	al,bl
	jnz	setbad
	stc
	ret

setspc:	xor	bh,bh		! Set special mode
	cmp	bl,#VIDEO_LAST_SPECIAL-VIDEO_FIRST_SPECIAL
	jnc	setbad
	add	bx,bx
	.word	0xa7ff, spec_inits	! JMP [BX+spec_inits]

setmenu:
	or	al,al		! 80x25 is an exception
	jz	set_80x25
	push	bx		! Set mode chosen from menu
	call	mode_table	! Build the mode table
	pop	ax
	shl	ax,#2
	add	si,ax
	cmp	si,di
	jnc	setbad
	mov	ax,(si)		! Fetch mode ID
_m_s:	jmp	mode_set

setres:
	push	bx		! Set mode chosen by its resolution
	call	mode_table
	pop	bx
	xchg	bh,bl
setr1:	lodsw
	cmp	ax,#ASK_VGA	! End of the list?
	jz	setbad
	lodsw
	cmp	ax,bx
	jnz	setr1
	mov	ax,(si-4)	! Fetch mode ID
	jmp	_m_s

!
! Recalculate vertical display end registers -- this fixes various
! inconsistencies of extended modes on many adapters. Called when
! the VIDEO_RECALC flag is set in the mode ID.
!

setrec:	sub	ah,#VIDEO_RECALC>>8	! Set the base mode
	call	mode_set
	jnc	rct3
	seg	gs			! Font size in pixels
	mov	ax,[0x485]
	seg	gs			! Number of rows
	mov	bl,[0x484]
	inc	bl
	mul	bl			! Number of visible
	dec	ax			! scan lines - 1
	mov	dx,#0x3d4
	mov	bx,ax
	mov	al,#0x12		! Lower 8 bits
	mov	ah,bl
	out	dx,ax
	mov	al,#0x07		! Bits 8 and 9 in the overflow register
	call	inidx
	xchg	ah,al
	and	ah,#0xbd
	shr	bh,#1
	jnc	rct1
	or	ah,#0x02
rct1:	shr	bh,#1
	jnc	rct2
	or	ah,#0x40
rct2:	mov	al,#0x07
	out	dx,ax
	stc
rct3:	ret

!
! Table of routines for setting of the special modes.
!

spec_inits:
	.word	set_80x25
	.word	set_8pixel
	.word	set_80x43
	.word	set_80x28
	.word	set_current
	.word	set_80x30
	.word	set_80x34
	.word	set_80x60
	.word	set_gfx

!
! Set the 80x25 mode. If already set, do nothing.
!

set_80x25:
	mov	[force_size],#0x5019	! Override possibly broken BIOS vars
use_80x25:
#ifdef CONFIG_VIDEO_400_HACK
	mov	ax,#0x1202	! Force 400 scan lines
	mov	bl,#0x30
	int	0x10
#else
	mov	ah,#0x0f	! Get current mode ID
	int	0x10
	cmp	ax,#0x5007	! Mode 7 (80x25 mono) is the only one available
	jz	st80		! on CGA/MDA/HGA and is also available on EGAM
	cmp	ax,#0x5003	! Unknown mode => force 80x25 color
	jnz	force3
st80:	cmpb	[adapter],#0	! CGA/MDA/HGA => mode 3/7 is always 80x25
	jz	set80
	seg	gs		! This is EGA+ -- beware of 80x50 etc.
	mov	al,[0x0484]
	or	al,al		! Some buggy BIOS'es set 0 rows
	jz	set80
	cmp	al,#24		! It's hopefully correct
	jz	set80
#endif /* CONFIG_VIDEO_400_HACK */
force3:	DO_STORE
	mov	ax,#0x0003	! Forced set
	int	0x10
set80:	stc
	ret

!
! Set the 80x50/80x43 8-pixel mode. Simple BIOS calls.
!

set_8pixel:
	DO_STORE
	call	use_80x25	! The base is 80x25
set_8pt:
	mov	ax,#0x1112	! Use 8x8 font
	xor	bl,bl
	int	0x10
	mov	ax,#0x1200	! Use alternate print screen
	mov	bl,#0x20
	int	0x10
	mov	ax,#0x1201	! Turn off cursor emulation
	mov	bl,#0x34
	int	0x10
	mov	ah,#0x01	! Define cursor (scan lines 6 to 7)
	mov	cx,#0x0607
	int	0x10
set_current:
	stc
	ret

!
! Set the 80x28 mode. This mode works on all VGA's, because it's a standard
! 80x25 mode with 14-point fonts instead of 16-point.
!

set_80x28:
	DO_STORE
	call	use_80x25	! The base is 80x25
set14:	mov	ax,#0x1111	! Use 9x14 font
	xor	bl,bl
	int	0x10
	mov	ah,#0x01	! Define cursor (scan lines 11 to 12)
	mov	cx,#0x0b0c
	int	0x10
	stc
	ret

!
! Set the 80x43 mode. This mode is works on all VGA's.
! It's a 350-scanline mode with 8-pixel font.
!

set_80x43:
	DO_STORE
	mov	ax,#0x1201	! Set 350 scans
	mov	bl,#0x30
	int	0x10
	mov	ax,#0x0003	! Reset video mode
	int	0x10
	jmp	set_8pt		! Use 8-pixel font

!
! Set the 80x30 mode (all VGA's). 480 scanlines, 16-pixel font.
!

set_80x30:
	call	use_80x25	! Start with real 80x25
	DO_STORE
	mov	dx,#0x3cc	! Get CRTC port
	in	al,dx
	mov	dl,#0xd4
	ror	al,#1		! Mono or color?
	jc	set48a
	mov	dl,#0xb4
set48a:	mov	ax,#0x0c11	! Vertical sync end (also unlocks CR0-7)
 	call	outidx
	mov	ax,#0x0b06	! Vertical total
 	call	outidx
	mov	ax,#0x3e07	! (Vertical) overflow
 	call	outidx
	mov	ax,#0xea10	! Vertical sync start
 	call	outidx
	mov	ax,#0xdf12	! Vertical display end
	call	outidx
	mov	ax,#0xe715	! Vertical blank start
 	call	outidx
	mov	ax,#0x0416	! Vertical blank end
 	call	outidx
	push	dx
	mov	dl,#0xcc	! Misc output register (read)
 	in	al,dx
 	mov	dl,#0xc2	! (write)
 	and	al,#0x0d	! Preserve clock select bits and color bit
 	or	al,#0xe2	! Set correct sync polarity
 	out	dx,al
	pop	dx
	mov	[force_size],#0x501e
	stc			! That's all.
	ret

!
! Set the 80x34 mode (all VGA's). 480 scans, 14-pixel font.
!

set_80x34:
	call	set_80x30	! Set 480 scans
	call	set14		! And 14-pt font
	mov	ax,#0xdb12	! VGA vertical display end
	mov	[force_size],#0x5022
setvde:	call	outidx
	stc
	ret

!
! Set the 80x60 mode (all VGA's). 480 scans, 8-pixel font.
!

set_80x60:
	call	set_80x30	! Set 480 scans
	call	set_8pt		! And 8-pt font
	mov	ax,#0xdf12	! VGA vertical display end
	mov	[force_size],#0x503c
	jmp	setvde

!
! Special hack for ThinkPad graphics
!

set_gfx:
#ifdef CONFIG_VIDEO_GFX_HACK
	mov	ax,# VIDEO_GFX_BIOS_AX
	mov	bx,# VIDEO_GFX_BIOS_BX
	int	0x10
	mov	[force_size],# VIDEO_GFX_DUMMY_RESOLUTION
	stc
#endif
	ret

#ifdef CONFIG_VIDEO_RETAIN

!
! Store screen contents to temporary buffer.
!

store_screen:
	cmpb	[do_restore],#0		! Already stored?
	jnz	stsr
	testb	[loadflags],#CAN_USE_HEAP	! Have we space for storing?
	jz	stsr
	push	ax
	push	bx
	push	[force_size]		! Don't force specific size
	mov	[force_size],#0
	call	mode_params		! Obtain params of current mode
	pop	[force_size]

	seg	fs
	mov	ah,[PARAM_VIDEO_LINES]
	seg	fs
	mov	al,[PARAM_VIDEO_COLS]
	mov	bx,ax			! BX=dimensions
	mul	ah
	mov	cx,ax			! CX=number of characters to store
	add	ax,ax			! Calculate image size
	add	ax,#modelist+1024+4
	cmp	ax,[heap_end_ptr]
	jnc	sts1			! Unfortunately, out of memory

	seg	fs			! Store mode params
	mov	ax,[PARAM_CURSOR_POS]
	lea	di,modelist+1024
	stosw
	mov	ax,bx
	stosw

	push	ds			! Store the screen
	mov	ds,[video_segment]
	xor	si,si
	rep
	movsw
	pop	ds
	incb	[do_restore]		! Screen will be restored later
sts1:	pop	bx
	pop	ax
stsr:	ret

!
! Restore screen contents from temporary buffer.
!

restore_screen:
	cmpb	[do_restore],#0		! Has the screen been stored?
	jz	res1
	call	mode_params		! Get parameters of current mode
	seg	fs
	mov	cl,[PARAM_VIDEO_LINES]
	seg	fs
	mov	ch,[PARAM_VIDEO_COLS]
	lea	si,modelist+1024	! Screen buffer
	lodsw				! Set cursor position
	mov	dx,ax
	cmp	dh,cl
	jc	res2
	mov	dh,cl
	dec	dh
res2:	cmp	dl,ch
	jc	res3
	mov	dl,ch
	dec	dl
res3:	mov	ah,#0x02
	mov	bh,#0x00
	int	0x10
	lodsw				! Display size
	mov	dl,ah			! DL=number of lines
	mov	ah,#0			! BX=physical length of orig. line
	mov	bx,ax
	cmp	dl,cl			! Too many?
	jc	res4
	push	ax
	mov	al,dl
	sub	al,cl
	mul	bl
	add	si,ax
	add	si,ax
	pop	ax
	mov	dl,cl
res4:	cmp	al,ch			! Too wide?
	jc	res5
	mov	al,ch			! AX=width of src. line
res5:	mov	cl,#0
	xchg	cl,ch
	mov	bp,cx			! BP=width of dest. line
	push	es
	mov	es,[video_segment]
	xor	di,di			! Move the data
	add	bx,bx			! Convert BX and BP to _bytes_
	add	bp,bp
res6:	push	si
	push	di
	mov	cx,ax
	rep
	movsw
	pop	di
	pop	si
	add	di,bp
	add	si,bx
	dec	dl
	jnz	res6
	pop	es			! Done
res1:	ret

#endif /* CONFIG_VIDEO_RETAIN */

!
! Write to indexed VGA register (AL=index, AH=data, DX=index reg. port)
!

outidx:	out	dx,al
	push	ax
	mov	al,ah
	inc	dx
	out	dx,al
	dec	dx
	pop	ax
	ret

!
! Build the table of video modes (stored after the setup.S code at the
! `modelist' label. Each video mode record looks like:
!	.word	MODE-ID		(our special mode ID (see above))
!	.byte	rows		(number of rows)
!	.byte	columns		(number of columns)
! Returns address of the end of the table in DI, the end is marked
! with a ASK_VGA ID.
!

mode_table:
	mov	di,[mt_end]	! Already filled?
	or	di,di
	jnz	mtab1x
	lea	di,modelist	! Store standard modes:

	mov	eax,#VIDEO_80x25 + 0x50190000	! The 80x25 mode (ALL)
	stosd
	mov	al,[adapter]	! CGA/MDA/HGA -- no more modes
	or	al,al
	jz	mtabe
	dec	al
	jnz	mtabv
	mov	eax,#VIDEO_8POINT + 0x502b0000	! The 80x43 EGA mode
	stosd
	jmp	mtabe
mtab1x:	jmp	mtab1

mtabv:	lea	si,vga_modes			! All modes for std VGA
	mov	cx,#vga_modes_end-vga_modes
	rep	! I'm unable to use movsw as I don't know how to store a half
	movsb	! of the expression above to cx without using explicit shr.

	cmpb	[scanning],#0			! Mode scan requested?
	jz	mscan1
	call	mode_scan
mscan1:

#ifdef CONFIG_VIDEO_LOCAL
	call	local_modes
#endif /* CONFIG_VIDEO_LOCAL */
#ifdef CONFIG_VIDEO_VESA
	call	vesa_modes			! Detect VESA VGA modes
#endif /* CONFIG_VIDEO_VESA */
#ifdef CONFIG_VIDEO_SVGA
	cmpb	[scanning],#0			! Bypass when scanning
	jnz	mscan2
	call	svga_modes			! Detect SVGA cards & modes
mscan2:
#endif /* CONFIG_VIDEO_SVGA */

mtabe:

#ifdef CONFIG_VIDEO_COMPACT
	lea	si,modelist	! Compact video mode list if requested.
	mov	dx,di
	mov	di,si
cmt1:	cmp	si,dx		! Scan all modes
	jz	cmt2
	lea	bx,modelist	! Find in previous entries
	mov	cx,(si+2)
cmt3:	cmp	si,bx
	jz	cmt4
	cmp	cx,(bx+2)	! Found => don't copy this entry
	jz	cmt5
	add	bx,#4
	jmp	cmt3

cmt4:	movsd			! Copy entry
	jmp	cmt1

cmt5:	add	si,#4		! Skip entry
	jmp	cmt1

cmt2:
#endif	/* CONFIG_VIDEO_COMPACT */

	mov	(di),#ASK_VGA	! End marker
	mov	[mt_end],di
mtab1:	lea	si,modelist	! Returning: SI=mode list, DI=list end
ret0:	ret

! Modes usable on all standard VGAs

vga_modes:
	.word	VIDEO_8POINT
	.word	0x5032		! 80x50
	.word	VIDEO_80x43
	.word	0x502b		! 80x43
	.word	VIDEO_80x28
	.word	0x501c		! 80x28
	.word	VIDEO_80x30
	.word	0x501e		! 80x30
	.word	VIDEO_80x34
	.word	0x5022		! 80x34
	.word	VIDEO_80x60
	.word	0x503c		! 80x60
#ifdef CONFIG_VIDEO_GFX_HACK
	.word	VIDEO_GFX_HACK
	.word	VIDEO_GFX_DUMMY_RESOLUTION
#endif
vga_modes_end:

!
! Detect VESA modes.
!

#ifdef CONFIG_VIDEO_VESA

vesa_modes:
	cmpb	[adapter],#2	! VGA only
	jnz	ret0
	mov	bp,di		! BP=original mode table end
	add	di,#0x200	! Buffer space
	mov	ax,#0x4f00	! VESA Get card info call
	int	#0x10
	mov	di,bp
	cmp	ax,#0x004f	! Successful?
	jnz	ret0
	cmp	(di+0x200),#0x4556
	jnz	ret0
	cmp	(di+0x202),#0x4153
	jnz	ret0
	mov	[card_name],#vesa_name	! Set name to "VESA VGA"
	push	gs
	lgs	si,(di+0x20e)	! GS:SI=mode list
	mov	cx,#128		! Iteration limit
vesa1:	seg	gs		! Get next mode in the list
	lodsw
	cmp	ax,#0xffff	! End of the table?
	jz	vesar
	cmp	ax,#0x0080	! Check validity of mode ID
	jc	vesa2
	or	ah,ah		! Valid ID's are 0x0000-0x007f and 0x0100-0x07ff
	jz	vesan		! [Certain BIOSes erroneously report 0x80-0xff]
	cmp	ax,#0x0800
	jnc	vesae
vesa2:	push	cx
	mov	cx,ax		! Get mode information structure
	mov	ax,#0x4f01
	int	0x10
	mov	bx,cx		! BX=mode number
	add	bh,#VIDEO_FIRST_VESA>>8
	pop	cx
	cmp	ax,#0x004f
	jnz	vesan		! Don't report errors (buggy BIOSES :-[ )
	mov	al,(di)		! Check capabilities. We require
	and	al,#0x19	! a color text mode.
	cmp	al,#0x09
	jnz	vesan
	cmp	(di+8),#0xb800	! Standard video memory address required
	jnz	vesan
	testb	(di),#2		! Mode characteristics supplied?
	mov	(di),bx		! Store mode number
	jz	vesa3
	xor	dx,dx
	mov	bx,(di+0x12)	! Width
	or	bh,bh
	jnz	vesan
	mov	(di+3),bl
	mov	ax,(di+0x14)	! Height
	or	ah,ah
	jnz	vesan
	mov	(di+2),al
	mul	bl
	cmp	ax,#8193	! Small enough for Linux console driver?
	jnc	vesan
	jmp	vesaok

vesa3:	sub	bx,#0x8108	! This mode has no detailed info specified,
	jc	vesan		! so it must be a standard VESA mode.
	cmp	bx,#5
	jnc	vesan
	mov	ax,(bx+vesa_text_mode_table)
	mov	(di+2),ax
vesaok:	add	di,#4		! The mode is valid. Store it.
vesan:	loop	vesa1		! Next mode. Limit exceeded => error
vesae:	lea	si,vesaer
	call	prtstr
	mov	di,bp		! Discard already found modes.
vesar:	pop	gs
	ret

!
! Dimensions of standard VESA text modes
!

vesa_text_mode_table:
	db	60, 80		! 0108
	db	25, 132		! 0109
	db	43, 132		! 010A
	db	50, 132		! 010B
	db	60, 132		! 010C

#endif	/* CONFIG_VIDEO_VESA */

!
! Scan for video modes. A bit dirty, but should work.
!

mode_scan:
	mov	cx,#0x0100	! Start with mode 0
scm1:	mov	ah,#0		! Test the mode
	mov	al,cl
	int	0x10
	mov	ah,#0x0f
	int	0x10
	cmp	al,cl
	jnz	scm2		! Mode not set
	mov	dx,#0x3c0	! Test if it's a text mode
	mov	al,#0x10		! Mode bits
	call	inidx
	and	al,#0x03
	jnz	scm2
	mov	dl,#0xce		! Another set of mode bits
	mov	al,#0x06
	call	inidx
	shr	al,#1
	jc	scm2
	mov	dl,#0xd4		! Cursor location
	mov	al,#0x0f
	call	inidx
	or	al,al
	jnz	scm2
	mov	ax,cx		! OK, store the mode
	stosw
	seg	gs		! Number of rows
	mov	al,[0x484]
	inc	al
	stosb
	seg	gs		! Number of columns
	mov	ax,[0x44a]
	stosb
scm2:	inc	cl
	jns	scm1
	mov	ax,#0x0003	! Return back to mode 3
	int	0x10
	ret

tstidx:	out	dx,ax		! OUT DX,AX and inidx
inidx:	out	dx,al		! Read from indexed VGA register
	inc	dx		! AL=index, DX=index reg port -> AL=data
	in	al,dx
	dec	dx
	ret

!
! Try to detect type of SVGA card and supply (usually approximate) video
! mode table for it.
!

#ifdef CONFIG_VIDEO_SVGA

svga_modes:
	lea	si,svga_table	! Test all known SVGA adapters
dosvga:	lodsw
	mov	bp,ax		! Default mode table
	or	ax,ax
	jz	didsv1
	lodsw			! Pointer to test routine
	push	si
	push	di
	push	es
	mov	bx,#0xc000
	mov	es,bx
	call	ax		! Call test routine
	pop	es
	pop	di
	pop	si
	or	bp,bp
	jz	dosvga
	mov	si,bp		! Found, copy the modes
	mov	ah,[svga_prefix]
cpsvga:	lodsb
	or	al,al
	jz	didsv
	stosw
	movsw
	jmp	cpsvga

didsv:	mov	[card_name],si	! Store pointer to card name
didsv1:	ret

!
! Table of all known SVGA cards. For each card, we store a pointer to
! a table of video modes supported by the card and a pointer to a routine
! used for testing of presence of the card. The video mode table is always
! followed by the name of the card or the chipset.
!

svga_table:
	.word	ati_md, ati_test
	.word	oak_md, oak_test
	.word	paradise_md, paradise_test
	.word	realtek_md, realtek_test
	.word	s3_md, s3_test
	.word	chips_md, chips_test
	.word	video7_md, video7_test
	.word	cirrus5_md, cirrus5_test
	.word	cirrus6_md, cirrus6_test
	.word	cirrus1_md, cirrus1_test
	.word	ahead_md, ahead_test
	.word	everex_md, everex_test
	.word	genoa_md, genoa_test
	.word	trident_md, trident_test
	.word	tseng_md, tseng_test
	.word	0

!
! Test routines and mode tables:
!

! S3 - The test algorithm was taken from the SuperProbe package
! for XFree86 1.2.1. Report bugs to Christoph.Niemann@linux.org

s3_test:
	mov	cx,#0x0f35	! we store some constants in cl/ch
	mov	dx,#0x03d4
	movb	al,#0x38
	call	inidx
	mov	bh,al		! store current value of CRT-register 0x38
	mov	ax,#0x0038
	call	outidx		! disable writing to special regs
	movb	al,cl		! check whether we can write special reg 0x35
	call	inidx
	movb	bl,al		! save the current value of CRT reg 0x35
	andb	al,#0xf0	! clear bits 0-3
	movb	ah,al
	movb	al,cl		! and write it to CRT reg 0x35
	call	outidx
	call	inidx		! now read it back
	andb	al,ch		! clear the upper 4 bits
	jz	s3_2		! the first test failed. But we have a
	movb	ah,bl		! second chance
	mov	al,cl
	call	outidx
	jmp	s3_1		! do the other tests
s3_2:	mov	ax,cx		! load ah with 0xf and al with 0x35
	orb	ah,bl		! set the upper 4 bits of ah with the orig value
	call	outidx		! write ...
	call	inidx		! ... and reread 
	andb	al,cl		! turn off the upper 4 bits
	push	ax
	movb	ah,bl		! restore old value in register 0x35
	movb	al,cl
	call	outidx
	pop	ax
	cmp	al,ch		! setting lower 4 bits was successful => bad
	je	no_s3		! writing is allowed => this is not an S3
s3_1:	mov	ax,#0x4838	! allow writing to special regs by putting
	call	outidx		! magic number into CRT-register 0x38
	movb	al,cl		! check whether we can write special reg 0x35
	call	inidx
	movb	bl,al
	andb	al,#0xf0
	movb	ah,al
	movb	al,cl
	call	outidx
	call	inidx
	andb	al,ch
	jnz	no_s3		! no, we can't write => no S3
	mov	ax,cx
	orb	ah,bl
	call	outidx
	call	inidx
	andb	al,ch
	push	ax
	movb	ah,bl		! restore old value in register 0x35
	movb	al,cl
	call	outidx
	pop	ax
	cmp	al,ch
	jne	no_s31		! writing not possible => no S3
	movb	al,#0x30
	call	inidx		! now get the S3 id ...
	lea	di,idS3
	mov	cx,#0x10
	repne
	scasb
	je	no_s31
	movb	ah,bh
	movb	al,#0x38
	jmp	s3rest
no_s3:	movb	al,#0x35	! restore CRT register 0x35
	movb	ah,bl
	call	outidx
no_s31:	xor	bp,bp		! Detection failed
s3rest:	movb	ah,bh
	movb	al,#0x38	! restore old value of CRT register 0x38
	br	outidx

idS3:	.byte	0x81, 0x82, 0x90, 0x91, 0x92, 0x93, 0x94, 0x95
	.byte	0xa0, 0xa1, 0xa2, 0xa3, 0xa4, 0xa5, 0xa8, 0xb0

s3_md:	.byte	0x54, 0x2b, 0x84
	.byte	0x55, 0x19, 0x84
	.byte	0
	.ascii	"S3"
	.byte	0

! ATI cards.

ati_test:
	lea 	si,idati
	mov	di,#0x31
	mov 	cx,#0x09
	repe
	cmpsb
	je	atiok
	xor	bp,bp
atiok:	ret

idati:	.ascii	"761295520"

ati_md:	.byte	0x23, 0x19, 0x84
	.byte	0x33, 0x2c, 0x84
	.byte	0x22, 0x1e, 0x64
	.byte	0x21, 0x19, 0x64
	.byte	0x58, 0x21, 0x50
	.byte	0x5b, 0x1e, 0x50
	.byte	0
	.ascii	"ATI"
	.byte	0

! AHEAD

ahead_test:
	mov	ax,#0x200f
	mov	dx,#0x3ce
	out	dx,ax
	inc	dx
	in	al,dx
	cmp	al,#0x20
	je	isahed
	cmp	al,#0x21
	je	isahed
	xor	bp,bp
isahed:	ret

ahead_md:
	.byte	0x22, 0x2c, 0x84
	.byte	0x23, 0x19, 0x84
	.byte	0x24, 0x1c, 0x84
	.byte	0x2f, 0x32, 0xa0
	.byte	0x32, 0x22, 0x50
	.byte	0x34, 0x42, 0x50
	.byte	0
	.ascii	"Ahead"
	.byte	0

! Chips & Tech.

chips_test:
	mov	dx,#0x3c3
	in	al,dx
	or	al,#0x10
	out	dx,al
	mov	dx,#0x104		
	in	al,dx
	mov	bl,al
	mov	dx,#0x3c3
	in	al,dx
	and	al,#0xef
	out	dx,al
	cmp	bl,#0xa5
	je	cantok
	xor	bp,bp
cantok:	ret

chips_md:
	.byte	0x60, 0x19, 0x84
	.byte	0x61, 0x32, 0x84
	.byte	0
	.ascii	"Chips & Technologies"
	.byte	0

! Cirrus Logic 5X0

cirrus1_test:
	mov	dx,#0x3d4
	mov	al,#0x0c
	out	dx,al
	inc	dx
	in	al,dx
	mov	bl,al
	xor	al,al
	out	dx,al
	dec	dx
	mov	al,#0x1f
	out	dx,al
	inc	dx
	in	al,dx
	mov	bh,al
	xor	ah,ah
	shl	al,#4
	mov	cx,ax
	mov	al,bh
	shr	al,#4
	add	cx,ax
	shl	cx,#8
	add	cx,#6
	mov	ax,cx
	mov	dx,#0x3c4
	out	dx,ax
	inc	dx
	in	al,dx
	and	al,al
	jnz	nocirr
	mov	al,bh
	out	dx,al
	in	al,dx
	cmp	al,#0x01
	je	iscirr
nocirr:	xor	bp,bp
iscirr: mov	dx,#0x3d4
	mov	al,bl
	xor	ah,ah
	shl	ax,#8
	add	ax,#0x0c
	out	dx,ax
	ret

cirrus1_md:
	.byte	0x1f, 0x19, 0x84
	.byte	0x20, 0x2c, 0x84
	.byte	0x22, 0x1e, 0x84
	.byte	0x31, 0x25, 0x64
	.byte	0
	.ascii	"Cirrus Logic 5X0"
	.byte	0

! Cirrus Logic 54XX

cirrus5_test:
	mov	dx,#0x3c4
	mov	al,#6
	call	inidx
	mov	bl,al			! BL=backup
	mov	ax,#6
	call	tstidx
	cmp	al,#0x0f
	jne	c5fail
	mov	ax,#0x1206
	call	tstidx
	cmp	al,#0x12
	jne	c5fail
	mov	al,#0x1e
	call	inidx
	mov	bh,al
	mov	ah,bh
	and	ah,#0xc0
	mov	al,#0x1e
	call	tstidx
	and	al,#0x3f
	jne	c5xx
	mov	al,#0x1e
	mov	ah,bh
	or	ah,#0x3f
	call	tstidx
	xor	al,#0x3f
	and	al,#0x3f
c5xx:	pushf
	mov	al,#0x1e
	mov	ah,bh
	out	dx,ax
	popf
	je	c5done
c5fail:	xor	bp,bp
c5done:	mov	al,#6
	mov	ah,bl
	out	dx,ax
	ret

cirrus5_md:
	.byte	0x14, 0x19, 0x84
	.byte	0x54, 0x2b, 0x84
	.byte	0
	.ascii	"Cirrus Logic 54XX"
	.byte	0

! Cirrus Logic 64XX -- no known extra modes, but must be identified, because
! it's misidentified by the Ahead test.

cirrus6_test:
	mov	dx,#0x3ce
	mov	al,#0x0a
	call	inidx
	mov	bl,al			! BL=backup
	mov	ax,#0xce0a
	call	tstidx
	or	al,al
	jne	c2fail
	mov	ax,#0xec0a
	call	tstidx
	cmp	al,#0x01
	jne	c2fail
	mov	al,#0xaa
	call	inidx	! 4X, 5X, 7X and 8X are valid 64XX chip ID's
	shr	al,#4
	sub	al,#4
	jz	c6done
	dec	al
	jz	c6done
	sub	al,#2
	jz	c6done
	dec	al
	jz	c6done
c2fail:	xor	bp,bp
c6done:	mov	al,#0x0a
	mov	ah,bl
	out	dx,ax
	ret

cirrus6_md:
	.byte	0
	.ascii	"Cirrus Logic 64XX"
	.byte	0

! Everex / Trident

everex_test:
	mov	ax,#0x7000
	xor	bx,bx
	int	0x10
	cmp	al,#0x70
	jne	noevrx
	shr	dx,#4
	cmp	dx,#0x678
	je	evtrid
	cmp	dx,#0x236
	jne	evrxok
evtrid:	lea	bp,trident_md
evrxok:	ret

noevrx:	xor	bp,bp
	ret

everex_md:
	.byte	0x03, 0x22, 0x50
	.byte	0x04, 0x3c, 0x50
	.byte	0x07, 0x2b, 0x64
	.byte	0x08, 0x4b, 0x64
	.byte	0x0a, 0x19, 0x84
	.byte	0x0b, 0x2c, 0x84
	.byte	0x16, 0x1e, 0x50
	.byte	0x18, 0x1b, 0x64
	.byte	0x21, 0x40, 0xa0
	.byte	0x40, 0x1e, 0x84
	.byte	0
	.ascii	"Everex/Trident"
	.byte	0

! Genoa.

genoa_test:
	lea	si,idgenoa		! Check Genoa 'clues'
	xor 	ax,ax
	seg es
	mov	al,[0x37]
	mov	di,ax
	mov	cx,#0x04
	dec	si
	dec	di
l1:	inc	si
	inc	di
	mov	al,(si)
	test	al,al
	jz	l2
	seg es
	cmp	al,(di)
l2:	loope 	l1
	or	cx,cx
	je	isgen
	xor	bp,bp
isgen:	ret

idgenoa: .byte	0x77, 0x00, 0x99, 0x66

genoa_md:
	.byte	0x58, 0x20, 0x50
	.byte	0x5a, 0x2a, 0x64
	.byte	0x60, 0x19, 0x84
	.byte	0x61, 0x1d, 0x84
	.byte	0x62, 0x20, 0x84
	.byte	0x63, 0x2c, 0x84
	.byte	0x64, 0x3c, 0x84
	.byte	0x6b, 0x4f, 0x64
	.byte	0x72, 0x3c, 0x50
	.byte	0x74, 0x42, 0x50
	.byte	0x78, 0x4b, 0x64
	.byte	0
	.ascii	"Genoa"
	.byte	0

! OAK

oak_test:
	lea	si,idoakvga
	mov	di,#0x08
	mov	cx,#0x08
	repe
	cmpsb
	je	isoak
	xor	bp,bp
isoak:	ret

idoakvga: .ascii  "OAK VGA "

oak_md: .byte	0x4e, 0x3c, 0x50
	.byte	0x4f, 0x3c, 0x84
	.byte	0x50, 0x19, 0x84
	.byte	0x51, 0x2b, 0x84
	.byte	0
	.ascii	"OAK"
	.byte	0

! WD Paradise.

paradise_test:
	lea	si,idparadise
	mov	di,#0x7d
	mov	cx,#0x04
	repe
	cmpsb
	je	ispara
	xor	bp,bp
ispara:	ret

idparadise:	.ascii	"VGA="

paradise_md:
	.byte	0x41, 0x22, 0x50
	.byte	0x47, 0x1c, 0x84
	.byte	0x55, 0x19, 0x84
	.byte	0x54, 0x2c, 0x84
	.byte	0
	.ascii	"Paradise"
	.byte	0

! Trident.

trident_test:
	mov	dx,#0x3c4
	mov	al,#0x0e
	out	dx,al
	inc	dx
	in	al,dx
	xchg	ah,al
	xor	al,al
	out	dx,al
	in	al,dx
	xchg	al,ah
	mov	bl,al		! Strange thing ... in the book this wasn't
	and	bl,#0x02	! necessary but it worked on my card which
	jz	setb2		! is a trident. Without it the screen goes
	and	al,#0xfd	! blurred ...
	jmp	clrb2		!
setb2:	or	al,#0x02	!
clrb2:	out	dx,al
	and	ah,#0x0f
	cmp	ah,#0x02
	je	istrid
	xor	bp,bp
istrid:	ret

trident_md:
	.byte	0x50, 0x1e, 0x50
	.byte	0x51, 0x2b, 0x50
	.byte	0x52, 0x3c, 0x50
	.byte	0x57, 0x19, 0x84
	.byte	0x58, 0x1e, 0x84
	.byte	0x59, 0x2b, 0x84
	.byte	0x5a, 0x3c, 0x84
	.byte	0
	.ascii	"Trident"
	.byte	0

! Tseng.

tseng_test:
	mov	dx,#0x3cd
	in	al,dx			! Could things be this simple ! :-)
	mov	bl,al
	mov	al,#0x55
	out	dx,al
	in	al,dx
	mov	ah,al
	mov	al,bl
	out	dx,al
	cmp	ah,#0x55
 	je	istsen
isnot:	xor	bp,bp
istsen:	ret

tseng_md:
	.byte	0x26, 0x3c, 0x50
	.byte	0x2a, 0x28, 0x64
	.byte	0x23, 0x19, 0x84
	.byte	0x24, 0x1c, 0x84
	.byte	0x22, 0x2c, 0x84
	.byte	0x21, 0x3c, 0x84
	.byte	0
	.ascii	"Tseng"
	.byte	0

! Video7.

video7_test:
	mov	dx,#0x3cc
	in	al,dx
	mov	dx,#0x3b4
	and	al,#0x01
	jz	even7
	mov	dx,#0x3d4
even7:	mov	al,#0x0c
	out	dx,al
	inc	dx
	in	al,dx
	mov	bl,al
	mov	al,#0x55
	out	dx,al
	in	al,dx
	dec	dx
	mov	al,#0x1f
	out	dx,al
	inc	dx
	in	al,dx
	mov	bh,al
	dec	dx
	mov	al,#0x0c
	out	dx,al
	inc	dx
	mov	al,bl
	out	dx,al
	mov	al,#0x55
	xor	al,#0xea
	cmp	al,bh
	jne	isnot
	movb	[svga_prefix],#VIDEO_FIRST_V7>>8	! Use special mode switching
	ret

video7_md:
	.byte	0x40, 0x2b, 0x50
	.byte	0x43, 0x3c, 0x50
	.byte	0x44, 0x3c, 0x64
	.byte	0x41, 0x19, 0x84
	.byte	0x42, 0x2c, 0x84
	.byte	0x45, 0x1c, 0x84
	.byte	0
	.ascii	"Video 7"
	.byte	0

! Realtek VGA

realtek_test:
	lea	si,idrtvga
	mov	di,#0x45
	mov	cx,#0x0b
	repe
	cmpsb
	je	isrt
	xor	bp,bp
isrt:	ret

idrtvga:	.ascii	"REALTEK VGA"

realtek_md:
	.byte	0x1a, 0x3c, 0x50
	.byte	0x1b, 0x19, 0x84
	.byte	0x1c, 0x1e, 0x84
	.byte	0x1d, 0x2b, 0x84
	.byte	0x1e, 0x3c, 0x84
	.byte	0
	.ascii	"REALTEK"
	.byte	0

#endif	/* CONFIG_VIDEO_SVGA */

!
! User-defined local mode table (VGA only)
!

#ifdef CONFIG_VIDEO_LOCAL

local_modes:
	lea	si,local_mode_table
locm1:	lodsw
	or	ax,ax
	jz	locm2
	stosw
	movsw
	jmp	locm1
locm2:	ret

! This is the table of local video modes which can be supplied manually
! by the user. Each entry consists of mode ID (word) and dimensions
! (byte for column count and another byte for row count). These modes
! are placed before all SVGA and VESA modes and override them if table
! compacting is enabled. The table must end with a zero word followed
! by NUL-terminated video adapter name.

local_mode_table:
	.word	0x0100		! Example: 40x25
	.byte	25,40
	.word	0
	.ascii	"Local"
	.byte	0

#endif	/* CONFIG_VIDEO_LOCAL */

!
! Read a key and return the ASCII code in al, scan code in ah
!

getkey:	xor	ah,ah
	int	0x16
	ret

!
! Read a key with a timeout of 30 seconds. The hardware clock is used to get
! the time.
!

getkt:	call	gettime
	add	al,#30		! Wait 30 seconds
	cmp	al,#60
	jl	lminute
	sub	al,#60
lminute:
	mov	cl,al
again:	mov	ah,#0x01
	int	0x16
	jnz	getkey		! key pressed, so get it
	call	gettime
	cmp	al,cl
	jne	again
	mov	al,#0x20	! timeout, return default char `space'
	ret

!
! Flush the keyboard buffer
!

flush:	mov	ah,#0x01
	int	0x16
	jz	empty
	xor	ah,ah
	int	0x16
	jmp	flush
empty:	ret

!
! Print hexadecimal number.
!

prthw:	push	ax
	mov	al,ah
	call	prthb
	pop	ax
prthb:	push	ax
	shr	al,#4
	call	prthn
	pop	ax
	and	al,#0x0f
prthn:	cmp	al,#0x0a
	jc	prth1
	add	al,#0x07
prth1:	add	al,#0x30
	br	prtchr

!
! Print decimal number (AL).
!

prtdec:	push	ax
	push	cx
	xor	ah,ah		! Clear ah
	mov	cl,#0x0a
	idiv	cl
	cmp	al,#0x09
	jbe	lt100
	call	prtdec
	jmp	skip10
lt100:	add	al,#0x30
	call	prtchr
skip10:	mov	al,ah
	add	al,#0x30
	call	prtchr	
	pop	cx
	pop	ax
	ret

!
! VIDEO_SELECT-only variables
!

mt_end:		.word	0	! End of video mode table if built
edit_buf:	.space	6	! Line editor buffer
card_name:	.word	0	! Pointer to adapter name
scanning:	.byte	0	! Performing mode scan
do_restore:	.byte	0	! Screen contents altered during mode change
svga_prefix:	.byte	VIDEO_FIRST_BIOS>>8	! Default prefix for BIOS modes

!
! Messages:
!

keymsg:		.ascii	"Press <RETURN> to see video modes available, "
		.ascii	"<SPACE> to continue or wait 30 secs"
		db	0x0d, 0x0a, 0
listhdr:	db	0x0d, 0x0a
		.ascii	"Mode:    COLSxROWS:"
crlft:		db	0x0d, 0x0a, 0
prompt:		db	0x0d, 0x0a
		.ascii	"Enter mode number or `scan': "
		db	0
unknt:		.ascii	"Unknown mode ID. Try again."
		db	0
badmdt:		.ascii	"You passed an undefined mode number."
		db	0x0d, 0x0a, 0
vesaer:		.ascii	"Error: Scanning of VESA modes failed. Please "
		.ascii	"report to <mj@k332.feld.cvut.cz>."
		db	0x0d, 0x0a, 0
old_name:	.ascii	"CGA/MDA/HGA"
		db	0
ega_name:	.ascii	"EGA"
		db	0
svga_name:	.ascii	" "
vga_name:	.ascii	"VGA"
		db	0
vesa_name:	.ascii	"VESA"
		db	0
name_bann:	.ascii	"Video adapter: "
		db	0

#endif /* CONFIG_VIDEO_SELECT */

!
! Other variables:
!

adapter:	.byte	0	! Video adapter: 0=CGA/MDA/HGA,1=EGA,2=VGA
video_segment:	.word	0xb800	! Video memory segment
force_size:	.word	0	! Use this size instead of the one in BIOS vars