summaryrefslogtreecommitdiffstats
path: root/sys/isa/sio.c
blob: 18d7a452fe2d0b465bfd6c58f2bbee19b2cca28c (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
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
1843
1844
1845
1846
1847
1848
1849
1850
1851
1852
1853
1854
1855
1856
1857
1858
1859
1860
1861
1862
1863
1864
1865
1866
1867
1868
1869
1870
1871
1872
1873
1874
1875
1876
1877
1878
1879
1880
1881
1882
1883
1884
1885
1886
1887
1888
1889
1890
1891
1892
1893
1894
1895
1896
1897
1898
1899
1900
1901
1902
1903
1904
1905
1906
1907
1908
1909
1910
1911
1912
1913
1914
1915
1916
1917
1918
1919
1920
1921
1922
1923
1924
1925
1926
1927
1928
1929
1930
1931
1932
1933
1934
1935
1936
1937
1938
1939
1940
1941
1942
1943
1944
1945
1946
1947
1948
1949
1950
1951
1952
1953
1954
1955
1956
1957
1958
1959
1960
1961
1962
1963
1964
1965
1966
1967
1968
1969
1970
1971
1972
1973
1974
1975
1976
1977
1978
1979
1980
1981
1982
1983
1984
1985
1986
1987
1988
1989
1990
1991
1992
1993
1994
1995
1996
1997
1998
1999
2000
2001
2002
2003
2004
2005
2006
2007
2008
2009
2010
2011
2012
2013
2014
2015
2016
2017
2018
2019
2020
2021
2022
2023
2024
2025
2026
2027
2028
2029
2030
2031
2032
2033
2034
2035
2036
2037
2038
2039
2040
2041
2042
2043
2044
2045
2046
2047
2048
2049
2050
2051
2052
2053
2054
2055
2056
2057
2058
2059
2060
2061
2062
2063
2064
2065
2066
2067
2068
2069
2070
2071
2072
2073
2074
2075
2076
2077
2078
2079
2080
2081
2082
2083
2084
2085
2086
2087
2088
2089
2090
2091
2092
2093
2094
2095
2096
2097
2098
2099
2100
2101
2102
2103
2104
2105
2106
2107
2108
2109
2110
2111
2112
2113
2114
2115
2116
2117
2118
2119
2120
2121
2122
2123
2124
2125
2126
2127
2128
2129
2130
2131
2132
2133
2134
2135
2136
2137
2138
2139
2140
2141
2142
2143
2144
2145
2146
2147
2148
2149
2150
2151
2152
2153
2154
2155
2156
2157
2158
2159
2160
2161
2162
2163
2164
2165
2166
2167
2168
2169
2170
2171
2172
2173
2174
2175
2176
2177
2178
2179
2180
2181
2182
2183
2184
2185
2186
2187
2188
2189
2190
2191
2192
2193
2194
2195
2196
2197
2198
2199
2200
2201
2202
2203
2204
2205
2206
2207
2208
2209
2210
2211
2212
2213
2214
2215
2216
2217
2218
2219
2220
2221
2222
2223
2224
2225
2226
2227
2228
2229
2230
2231
2232
2233
2234
2235
2236
2237
2238
2239
2240
2241
2242
2243
2244
2245
2246
2247
2248
2249
2250
2251
2252
2253
2254
2255
2256
2257
2258
2259
2260
2261
2262
2263
2264
2265
2266
2267
2268
2269
2270
2271
2272
2273
2274
2275
2276
2277
2278
2279
2280
2281
2282
2283
2284
2285
2286
2287
2288
2289
2290
2291
2292
2293
2294
2295
2296
2297
2298
2299
2300
2301
2302
2303
2304
2305
2306
2307
2308
2309
2310
2311
2312
2313
2314
2315
2316
2317
2318
2319
2320
2321
2322
2323
2324
2325
2326
2327
2328
2329
2330
2331
2332
2333
2334
2335
2336
2337
2338
2339
2340
2341
2342
2343
2344
2345
2346
2347
2348
2349
2350
2351
2352
2353
2354
2355
2356
2357
2358
2359
2360
2361
2362
2363
2364
2365
2366
2367
2368
2369
2370
2371
2372
2373
2374
2375
2376
2377
2378
2379
2380
2381
2382
2383
2384
2385
2386
2387
2388
2389
2390
2391
2392
2393
2394
2395
2396
2397
2398
2399
2400
2401
2402
2403
2404
2405
2406
2407
2408
2409
2410
2411
2412
2413
2414
2415
2416
2417
2418
2419
2420
2421
2422
2423
2424
2425
2426
2427
2428
2429
2430
2431
2432
2433
2434
2435
2436
2437
2438
2439
2440
2441
2442
2443
2444
2445
2446
2447
2448
2449
2450
2451
2452
2453
2454
2455
2456
2457
2458
2459
2460
2461
2462
2463
2464
2465
2466
2467
2468
2469
2470
2471
2472
2473
2474
2475
2476
2477
2478
2479
2480
2481
2482
2483
2484
2485
2486
2487
2488
2489
2490
2491
2492
2493
2494
2495
2496
2497
2498
2499
2500
2501
2502
2503
2504
2505
2506
2507
2508
2509
2510
2511
2512
2513
2514
2515
2516
2517
2518
2519
2520
2521
2522
2523
2524
2525
2526
2527
2528
2529
2530
2531
2532
2533
2534
2535
2536
2537
2538
2539
2540
2541
2542
2543
2544
2545
2546
2547
2548
2549
2550
2551
2552
2553
2554
2555
2556
2557
2558
2559
/*-
 * Copyright (c) 1991 The Regents of the University of California.
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. All advertising materials mentioning features or use of this software
 *    must display the following acknowledgement:
 *	This product includes software developed by the University of
 *	California, Berkeley and its contributors.
 * 4. Neither the name of the University nor the names of its contributors
 *    may be used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 *
 *	from: @(#)com.c	7.5 (Berkeley) 5/16/91
 *	$Id: sio.c,v 1.115 1995/10/22 15:38:05 bde Exp $
 */

#include "sio.h"
#if NSIO > 0
/*
 * Serial driver, based on 386BSD-0.1 com driver.
 * Mostly rewritten to use pseudo-DMA.
 * Works for National Semiconductor NS8250-NS16550AF UARTs.
 * COM driver, based on HP dca driver.
 *
 * Changes for PC-Card integration:
 *	- Added PC-Card driver table and handlers
 */
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/reboot.h>
#include <sys/ioctl.h>
#include <sys/tty.h>
#include <sys/proc.h>
#include <sys/user.h>
#include <sys/conf.h>
#include <sys/dkstat.h>
#include <sys/file.h>
#include <sys/uio.h>
#include <sys/kernel.h>
#include <sys/malloc.h>
#include <sys/syslog.h>
#include <sys/devconf.h>

#include <machine/clock.h>

#include <i386/isa/icu.h>	/* XXX just to get at `imen' */
#include <i386/isa/isa.h>
#include <i386/isa/isa_device.h>
#include <i386/isa/sioreg.h>
#include <i386/isa/ic/ns16550.h>

#define	LOTS_OF_EVENTS	64	/* helps separate urgent events from input */
#define	RB_I_HIGH_WATER	(TTYHOG - 2 * RS_IBUFSIZE)
#define	RS_IBUFSIZE	256

#define	CALLOUT_MASK		0x80
#define	CONTROL_MASK		0x60
#define	CONTROL_INIT_STATE	0x20
#define	CONTROL_LOCK_STATE	0x40
#define	DEV_TO_UNIT(dev)	(MINOR_TO_UNIT(minor(dev)))
#define	MINOR_MAGIC_MASK	(CALLOUT_MASK | CONTROL_MASK)
#define	MINOR_TO_UNIT(mynor)	((mynor) & ~MINOR_MAGIC_MASK)

#ifdef COM_MULTIPORT
/* checks in flags for multiport and which is multiport "master chip"
 * for a given card
 */
#define	COM_ISMULTIPORT(dev)	((dev)->id_flags & 0x01)
#define	COM_MPMASTER(dev)	(((dev)->id_flags >> 8) & 0x0ff)
#define	COM_NOTAST4(dev)	((dev)->id_flags & 0x04)
#endif /* COM_MULTIPORT */

#define	COM_LOSESOUTINTS(dev)	((dev)->id_flags & 0x08)
#define	COM_NOFIFO(dev)		((dev)->id_flags & 0x02)
#define	COM_VERBOSE(dev)	((dev)->id_flags & 0x80)

#define	com_scr		7	/* scratch register for 16450-16550 (R/W) */

#include "crd.h"
#if NCRD > 0
#include <pccard/card.h>
#include <pccard/slot.h>
#endif /* NCRD > 0 */

/*
 * Input buffer watermarks.
 * The external device is asked to stop sending when the buffer exactly reaches
 * high water, or when the high level requests it.
 * The high level is notified immediately (rather than at a later clock tick)
 * when this watermark is reached.
 * The buffer size is chosen so the watermark should almost never be reached.
 * The low watermark is invisibly 0 since the buffer is always emptied all at
 * once.
 */
#define	RS_IHIGHWATER (3 * RS_IBUFSIZE / 4)

/*
 * com state bits.
 * (CS_BUSY | CS_TTGO) and (CS_BUSY | CS_TTGO | CS_ODEVREADY) must be higher
 * than the other bits so that they can be tested as a group without masking
 * off the low bits.
 *
 * The following com and tty flags correspond closely:
 *	CS_BUSY		= TS_BUSY (maintained by comstart(), siopoll() and
 *				   siostop())
 *	CS_TTGO		= ~TS_TTSTOP (maintained by comparam() and comstart())
 *	CS_CTS_OFLOW	= CCTS_OFLOW (maintained by comparam())
 *	CS_RTS_IFLOW	= CRTS_IFLOW (maintained by comparam())
 * TS_FLUSH is not used.
 * XXX I think TIOCSETA doesn't clear TS_TTSTOP when it clears IXON.
 * XXX CS_*FLOW should be CF_*FLOW in com->flags (control flags not state).
 */
#define	CS_BUSY		0x80	/* output in progress */
#define	CS_TTGO		0x40	/* output not stopped by XOFF */
#define	CS_ODEVREADY	0x20	/* external device h/w ready (CTS) */
#define	CS_CHECKMSR	1	/* check of MSR scheduled */
#define	CS_CTS_OFLOW	2	/* use CTS output flow control */
#define	CS_DTR_OFF	0x10	/* DTR held off */
#define	CS_ODONE	4	/* output completed */
#define	CS_RTS_IFLOW	8	/* use RTS input flow control */

static	char const * const	error_desc[] = {
#define	CE_OVERRUN			0
	"silo overflow",
#define	CE_INTERRUPT_BUF_OVERFLOW	1
	"interrupt-level buffer overflow",
#define	CE_TTY_BUF_OVERFLOW		2
	"tty-level buffer overflow",
};

#define	CE_NTYPES			3
#define	CE_RECORD(com, errnum)		(++(com)->delta_error_counts[errnum])

/* types.  XXX - should be elsewhere */
typedef u_int	Port_t;		/* hardware port */
typedef u_char	bool_t;		/* boolean */

/* queue of linear buffers */
struct lbq {
	u_char	*l_head;	/* next char to process */
	u_char	*l_tail;	/* one past the last char to process */
	struct lbq *l_next;	/* next in queue */
	bool_t	l_queued;	/* nonzero if queued */
};

/* com device structure */
struct com_s {
	u_char	state;		/* miscellaneous flag bits */
	bool_t  active_out;	/* nonzero if the callout device is open */
	u_char	cfcr_image;	/* copy of value written to CFCR */
	u_char	ftl;		/* current rx fifo trigger level */
	u_char	ftl_init;	/* ftl_max for next open() */
	u_char	ftl_max;	/* maximum ftl for curent open() */
	bool_t	hasfifo;	/* nonzero for 16550 UARTs */
	bool_t	loses_outints;	/* nonzero if device loses output interrupts */
	u_char	mcr_image;	/* copy of value written to MCR */
#ifdef COM_MULTIPORT
	bool_t	multiport;	/* is this unit part of a multiport device? */
#endif /* COM_MULTIPORT */
	bool_t	no_irq;		/* nonzero if irq is not attached */
	bool_t  gone;		/* hardware disappeared */
	bool_t	poll;		/* nonzero if polling is required */
	bool_t	poll_output;	/* nonzero if polling for output is required */
	int	unit;		/* unit	number */
	int	dtr_wait;	/* time to hold DTR down on close (* 1/hz) */
	u_int	tx_fifo_size;
	u_int	wopeners;	/* # processes waiting for DCD in open() */

	/*
	 * The high level of the driver never reads status registers directly
	 * because there would be too many side effects to handle conveniently.
	 * Instead, it reads copies of the registers stored here by the
	 * interrupt handler.
	 */
	u_char	last_modem_status;	/* last MSR read by intr handler */
	u_char	prev_modem_status;	/* last MSR handled by high level */

	u_char	hotchar;	/* ldisc-specific char to be handled ASAP */
	u_char	*ibuf;		/* start of input buffer */
	u_char	*ibufend;	/* end of input buffer */
	u_char	*ihighwater;	/* threshold in input buffer */
	u_char	*iptr;		/* next free spot in input buffer */

	struct lbq	obufq;	/* head of queue of output buffers */
	struct lbq	obufs[2];	/* output buffers */

	Port_t	data_port;	/* i/o ports */
	Port_t	int_id_port;
	Port_t	iobase;
	Port_t	modem_ctl_port;
	Port_t	line_status_port;
	Port_t	modem_status_port;

	struct tty	*tp;	/* cross reference */

	/* Initial state. */
	struct termios	it_in;	/* should be in struct tty */
	struct termios	it_out;

	/* Lock state. */
	struct termios	lt_in;	/* should be in struct tty */
	struct termios	lt_out;

	bool_t	do_timestamp;
	struct timeval	timestamp;

	u_long	bytes_in;	/* statistics */
	u_long	bytes_out;
	u_int	delta_error_counts[CE_NTYPES];
	u_long	error_counts[CE_NTYPES];

	/*
	 * Ping-pong input buffers.  The extra factor of 2 in the sizes is
	 * to allow for an error byte for each input byte.
	 */
#define	CE_INPUT_OFFSET		RS_IBUFSIZE
	u_char	ibuf1[2 * RS_IBUFSIZE];
	u_char	ibuf2[2 * RS_IBUFSIZE];

	/*
	 * Data area for output buffers.  Someday we should build the output
	 * buffer queue without copying data.
	 */
	u_char	obuf1[256];
	u_char	obuf2[256];
};

/*
 * XXX public functions in drivers should be declared in headers produced
 * by `config', not here.
 */

/* Interrupt handling entry points. */
void	siointr		__P((int unit));
void	siointrts	__P((int unit));
void	siopoll		__P((void));

/* Device switch entry points. */
#define	sioreset	noreset
#define	siommap		nommap
#define	siostrategy	nostrategy

static	int	sioattach	__P((struct isa_device *dev));
static	timeout_t siodtrwakeup;
static	void	comhardclose	__P((struct com_s *com));
static	void	siointr1	__P((struct com_s *com));
static	int	commctl		__P((struct com_s *com, int bits, int how));
static	int	comparam	__P((struct tty *tp, struct termios *t));
static	int	sioprobe	__P((struct isa_device *dev));
static	void	sioregisterdev	__P((struct isa_device *id));
static	void	siosettimeout	__P((void));
static	void	comstart	__P((struct tty *tp));
static	timeout_t comwakeup;
static	void	disc_optim	__P((struct tty	*tp, struct termios *t,
				     struct com_s *com));

#ifdef DSI_SOFT_MODEM
static  int 	LoadSoftModem   __P((int unit,int base_io, u_long size, u_char *ptr));
#endif /* DSI_SOFT_MODEM */

/* table and macro for fast conversion from a unit number to its com struct */
static	struct com_s	*p_com_addr[NSIO];
#define	com_addr(unit)	(p_com_addr[unit])

static  struct timeval	intr_timestamp;

struct isa_driver	siodriver = {
	sioprobe, sioattach, "sio"
};

static	int	comconsole = -1;
static	speed_t	comdefaultrate = TTYDEF_SPEED;
static	u_int	com_events;	/* input chars + weighted output completions */
static	int	commajor;
static	int	sio_timeout;
static	int	sio_timeouts_until_log;
#if 0 /* XXX */
static struct tty	*sio_tty[NSIO];
#else
static struct tty	sio_tty[NSIO];
static	int	nsio_tty = NSIO;
#endif

#ifdef KGDB
#include <machine/remote-sl.h>

extern	int	kgdb_dev;
extern	int	kgdb_rate;
extern	int	kgdb_debug_init;
#endif

static	struct speedtab comspeedtab[] = {
	0,	0,
	50,	COMBRD(50),
	75,	COMBRD(75),
	110,	COMBRD(110),
	134,	COMBRD(134),
	150,	COMBRD(150),
	200,	COMBRD(200),
	300,	COMBRD(300),
	600,	COMBRD(600),
	1200,	COMBRD(1200),
	1800,	COMBRD(1800),
	2400,	COMBRD(2400),
	4800,	COMBRD(4800),
	9600,	COMBRD(9600),
	19200,	COMBRD(19200),
	38400,	COMBRD(38400),
	57600,	COMBRD(57600),
	115200,	COMBRD(115200),
	-1,	-1
};

/* XXX - configure this list */
static Port_t likely_com_ports[] = { 0x3f8, 0x2f8, 0x3e8, 0x2e8, };

static struct kern_devconf kdc_sio[NSIO] = { {
	0, 0, 0,		/* filled in by dev_attach */
	"sio", 0, { MDDT_ISA, 0, "tty" },
	isa_generic_externalize, 0, 0, ISA_EXTERNALLEN,
	&kdc_isa0,		/* parent */
	0,			/* parentdata */
	DC_UNCONFIGURED,	/* state */
	"Serial port",
	DC_CLS_SERIAL		/* class */
} };
#if NCRD > 0
/*
 *	PC-Card (PCMCIA) specific code.
 */
static int card_intr(struct pccard_dev *);	/* Interrupt handler */
void siounload(struct pccard_dev *);	/* Disable driver */
void siosuspend(struct pccard_dev *);	/* Suspend driver */
static int sioinit(struct pccard_dev *, int);	/* init device */

static struct pccard_drv sio_info =
	{
	"sio",
	card_intr,
	siounload,
	siosuspend,
	sioinit,
	0,			/* Attributes - presently unused */
	&tty_imask		/* Interrupt mask for device */
				/* This should also include net_imask?? */
	};
/*
 * Called when a power down is wanted. Shuts down the
 * device and configures the device as unavailable (but
 * still loaded...). A resume is done by calling
 * sioinit with first=0. This is called when the user suspends
 * the system, or the APM code suspends the system.
 */
void
siosuspend(struct pccard_dev *dp)
{
	printf("sio%d: suspending\n", dp->isahd.id_unit);
}
/*
 *	Initialize the device - called from Slot manager.
 *	if first is set, then initially check for
 *	the device's existence before initialising it.
 *	Once initialised, the device table may be set up.
 */
int
sioinit(struct pccard_dev *dp, int first)
{
/*
 *	validate unit number.
 */
	if (first)
		{
		if (dp->isahd.id_unit >= NSIO)
			return(ENODEV);
/*
 *	Make sure it isn't already probed.
 */
		if (com_addr(dp->isahd.id_unit))
			return(EBUSY);
/*
 *	Probe the device. If a value is returned, the
 *	device was found at the location.
 */
		if (sioprobe(&dp->isahd)==0)
			return(ENXIO);
		if (sioattach(&dp->isahd)==0)
			return(ENXIO);
		}
/*
 *	XXX TODO:
 *	If it was already inited before, the device structure
 *	should be already initialised. Here we should
 *	reset (and possibly restart) the hardware, but
 *	I am not sure of the best way to do this...
 */
	return(0);
}
/*
 *	siounload - unload the driver and clear the table.
 *	XXX TODO:
 *	This is called usually when the card is ejected, but
 *	can be caused by the modunload of a controller driver.
 *	The idea is reset the driver's view of the device
 *	and ensure that any driver entry points such as
 *	read and write do not hang.
 */
void
siounload(struct pccard_dev *dp)
{
	struct com_s	*com;
	struct tty	*tp;
	int	s,unit,nowhere;

	com = com_addr(dp->isahd.id_unit);
	if (!com->iobase) {
		printf("sio%d already unloaded!\n",dp->isahd.id_unit);
		return;
	}
	kdc_sio[com->unit].kdc_state = DC_UNCONFIGURED;
	kdc_sio[com->unit].kdc_description = "Serial port";
	if (com->tp && (com->tp->t_state & TS_ISOPEN)) {
		com->gone = 1;
		printf("sio%d: unload\n", dp->isahd.id_unit);
		com->tp->t_gen++;
		ttyclose(com->tp);
		ttwakeup(com->tp);
		ttwwakeup(com->tp);
	} else {
		com_addr(com->unit) = NULL;
		bzero(com, sizeof *com);
		free(com,M_TTYS);
		printf("sio%d: unload,gone\n", dp->isahd.id_unit);
	}
}

/*
 *	card_intr - Shared interrupt called from
 *	front end of PC-Card handler.
 */
static int
card_intr(struct pccard_dev *dp)
{
	struct com_s	*com;
	com = com_addr(dp->isahd.id_unit);
	if (com && !com_addr(dp->isahd.id_unit)->gone)
		siointr1(com_addr(dp->isahd.id_unit));
	return(1);
}
#endif /* NCRD > 0 */

static void
sioregisterdev(id)
	struct isa_device *id;
{
	int	unit;

	unit = id->id_unit;
/*
 *	If already registered, don't try to re-register.
 */
	if (kdc_sio[unit].kdc_isa)
		return;
	if (unit != 0)
		kdc_sio[unit] = kdc_sio[0];
	kdc_sio[unit].kdc_state = DC_UNCONFIGURED;
	kdc_sio[unit].kdc_description = "Serial port";
	kdc_sio[unit].kdc_unit = unit;
	kdc_sio[unit].kdc_isa = id;
	dev_attach(&kdc_sio[unit]);
}

static int
sioprobe(dev)
	struct isa_device	*dev;
{
	static bool_t	already_init;
	Port_t		*com_ptr;
	bool_t		failures[10];
	int		fn;
	struct isa_device	*idev;
	Port_t		iobase;
	u_char		mcr_image;
	int		result;

	sioregisterdev(dev);

	if (!already_init) {
		/*
		 * Turn off MCR_IENABLE for all likely serial ports.  An unused
		 * port with its MCR_IENABLE gate open will inhibit interrupts
		 * from any used port that shares the interrupt vector.
		 * XXX the gate enable is elsewhere for some multiports.
		 */
		for (com_ptr = likely_com_ports;
		     com_ptr < &likely_com_ports[sizeof likely_com_ports
						 / sizeof likely_com_ports[0]];
		     ++com_ptr)
			outb(*com_ptr + com_mcr, 0);
#if NCRD > 0
/*
 *	If PC-Card probe required, then register driver with
 *	slot manager.
 */
		pccard_add_driver(&sio_info);
#endif /* NCRD > 0 */
		already_init = TRUE;
	}

	/*
	 * If the device is on a multiport card and has an AST/4
	 * compatible interrupt control register, initialize this
	 * register and prepare to leave MCR_IENABLE clear in the mcr.
	 * Otherwise, prepare to set MCR_IENABLE in the mcr.
	 * Point idev to the device struct giving the correct id_irq.
	 * This is the struct for the master device if there is one.
	 */
	idev = dev;
	mcr_image = MCR_IENABLE;
#ifdef COM_MULTIPORT
	if (COM_ISMULTIPORT(dev)) {
		idev = find_isadev(isa_devtab_tty, &siodriver,
				   COM_MPMASTER(dev));
		if (idev == NULL) {
			printf("sio%d: master device %d not configured\n",
			       dev->id_unit, COM_MPMASTER(dev));
			return (0);
		}
		if (!COM_NOTAST4(dev)) {
			outb(idev->id_iobase + com_scr,
			     idev->id_irq ? 0x80 : 0);
			mcr_image = 0;
		}
	}
#endif /* COM_MULTIPORT */
	if (idev->id_irq == 0)
		mcr_image = 0;

	bzero(failures, sizeof failures);
	iobase = dev->id_iobase;

	/*
	 * We don't want to get actual interrupts, just masked ones.
	 * Interrupts from this line should already be masked in the ICU,
	 * but mask them in the processor as well in case there are some
	 * (misconfigured) shared interrupts.
	 */
	disable_intr();
/* EXTRA DELAY? */

	/*
	 * XXX DELAY() reenables CPU interrupts.  This is a problem for
	 * shared interrupts after the first device using one has been
	 * successfully probed - config_isadev() has enabled the interrupt
	 * in the ICU.
	 */
	outb(IO_ICU1 + 1, 0xff);

	/*
	 * Initialize the speed and the word size and wait long enough to
	 * drain the maximum of 16 bytes of junk in device output queues.
	 * The speed is undefined after a master reset and must be set
	 * before relying on anything related to output.  There may be
	 * junk after a (very fast) soft reboot and (apparently) after
	 * master reset.
	 * XXX what about the UART bug avoided by waiting in comparam()?
	 * We don't want to to wait long enough to drain at 2 bps.
	 */
	outb(iobase + com_cfcr, CFCR_DLAB);
	outb(iobase + com_dlbl, COMBRD(9600) & 0xff);
	outb(iobase + com_dlbh, (u_int) COMBRD(9600) >> 8);
	outb(iobase + com_cfcr, CFCR_8BITS);
	DELAY((16 + 1) * 1000000 / (9600 / 10));

	/*
	 * Enable the interrupt gate and disable device interupts.  This
	 * should leave the device driving the interrupt line low and
	 * guarantee an edge trigger if an interrupt can be generated.
	 */
/* EXTRA DELAY? */
	outb(iobase + com_mcr, mcr_image);
	outb(iobase + com_ier, 0);

	/*
	 * Attempt to set loopback mode so that we can send a null byte
	 * without annoying any external device.
	 */
/* EXTRA DELAY? */
	outb(iobase + com_mcr, mcr_image | MCR_LOOPBACK);

	/*
	 * Attempt to generate an output interrupt.  On 8250's, setting
	 * IER_ETXRDY generates an interrupt independent of the current
	 * setting and independent of whether the THR is empty.  On 16450's,
	 * setting IER_ETXRDY generates an interrupt independent of the
	 * current setting.  On 16550A's, setting IER_ETXRDY only
	 * generates an interrupt when IER_ETXRDY is not already set.
	 */
	outb(iobase + com_ier, IER_ETXRDY);

	/*
	 * On some 16x50 incompatibles, setting IER_ETXRDY doesn't generate
	 * an interrupt.  They'd better generate one for actually doing
	 * output.  Loopback may be broken on the same incompatibles but
	 * it's unlikely to do more than allow the null byte out.
	 */
	outb(iobase + com_data, 0);
	DELAY((1 + 2) * 1000000 / (9600 / 10));

	/*
	 * Turn off loopback mode so that the interrupt gate works again
	 * (MCR_IENABLE was hidden).  This should leave the device driving
	 * an interrupt line high.  It doesn't matter if the interrupt
	 * line oscillates while we are not looking at it, since interrupts
	 * are disabled.
	 */
/* EXTRA DELAY? */
	outb(iobase + com_mcr, mcr_image);

	/*
	 * Check that
	 *	o the CFCR, IER and MCR in UART hold the values written to them
	 *	  (the values happen to be all distinct - this is good for
	 *	  avoiding false positive tests from bus echoes).
	 *	o an output interrupt is generated and its vector is correct.
	 *	o the interrupt goes away when the IIR in the UART is read.
	 */
/* EXTRA DELAY? */
	failures[0] = inb(iobase + com_cfcr) - CFCR_8BITS;
	failures[1] = inb(iobase + com_ier) - IER_ETXRDY;
	failures[2] = inb(iobase + com_mcr) - mcr_image;
	if (idev->id_irq != 0)
		failures[3] = isa_irq_pending(idev) ? 0 : 1;
	failures[4] = (inb(iobase + com_iir) & IIR_IMASK) - IIR_TXRDY;
	if (idev->id_irq != 0)
		failures[5] = isa_irq_pending(idev) ? 1	: 0;
	failures[6] = (inb(iobase + com_iir) & IIR_IMASK) - IIR_NOPEND;

	/*
	 * Turn off all device interrupts and check that they go off properly.
	 * Leave MCR_IENABLE alone.  For ports without a master port, it gates
	 * the OUT2 output of the UART to
	 * the ICU input.  Closing the gate would give a floating ICU input
	 * (unless there is another device driving at) and spurious interrupts.
	 * (On the system that this was first tested on, the input floats high
	 * and gives a (masked) interrupt as soon as the gate is closed.)
	 */
	outb(iobase + com_ier, 0);
	outb(iobase + com_cfcr, CFCR_8BITS);	/* dummy to avoid bus echo */
	failures[7] = inb(iobase + com_ier);
	if (idev->id_irq != 0)
		failures[8] = isa_irq_pending(idev) ? 1	: 0;
	failures[9] = (inb(iobase + com_iir) & IIR_IMASK) - IIR_NOPEND;

	outb(IO_ICU1 + 1, imen);	/* XXX */
	enable_intr();

	result = IO_COMSIZE;
	for (fn = 0; fn < sizeof failures; ++fn)
		if (failures[fn]) {
			outb(iobase + com_mcr, 0);
			result = 0;
			if (COM_VERBOSE(dev))
				printf("sio%d: probe test %d failed\n",
				       dev->id_unit, fn);
		}
	return (result);
}

static int
sioattach(isdp)
	struct isa_device	*isdp;
{
	struct com_s	*com;
	Port_t		iobase;
	int		s;
	int		unit;

	isdp->id_ri_flags |= RI_FAST;
	iobase = isdp->id_iobase;
	unit = isdp->id_unit;
	com = malloc(sizeof *com, M_TTYS, M_NOWAIT);
	if (com == NULL)
		return (0);

	/*
	 * sioprobe() has initialized the device registers as follows:
	 *	o cfcr = CFCR_8BITS.
	 *	  It is most important that CFCR_DLAB is off, so that the
	 *	  data port is not hidden when we enable interrupts.
	 *	o ier = 0.
	 *	  Interrupts are only enabled when the line is open.
	 *	o mcr = MCR_IENABLE, or 0 if the port has AST/4 compatible
	 *	  interrupt control register or the config specifies no irq.
	 *	  Keeping MCR_DTR and MCR_RTS off might stop the external
	 *	  device from sending before we are ready.
	 */
	bzero(com, sizeof *com);
	com->unit = unit;
	com->cfcr_image = CFCR_8BITS;
	com->dtr_wait = 3 * hz;
	com->loses_outints = COM_LOSESOUTINTS(isdp) != 0;
	com->no_irq = isdp->id_irq == 0;
	com->tx_fifo_size = 1;
	com->iptr = com->ibuf = com->ibuf1;
	com->ibufend = com->ibuf1 + RS_IBUFSIZE;
	com->ihighwater = com->ibuf1 + RS_IHIGHWATER;
	com->obufs[0].l_head = com->obuf1;
	com->obufs[1].l_head = com->obuf2;

	com->iobase = iobase;
	com->data_port = iobase + com_data;
	com->int_id_port = iobase + com_iir;
	com->modem_ctl_port = iobase + com_mcr;
	com->mcr_image = inb(com->modem_ctl_port);
	com->line_status_port = iobase + com_lsr;
	com->modem_status_port = iobase + com_msr;

	/*
	 * We don't use all the flags from <sys/ttydefaults.h> since they
	 * are only relevant for logins.  It's important to have echo off
	 * initially so that the line doesn't start blathering before the
	 * echo flag can be turned off.
	 */
	com->it_in.c_iflag = 0;
	com->it_in.c_oflag = 0;
	com->it_in.c_cflag = TTYDEF_CFLAG;
	com->it_in.c_lflag = 0;
	if (unit == comconsole) {
		com->it_in.c_iflag = TTYDEF_IFLAG;
		com->it_in.c_oflag = TTYDEF_OFLAG;
		com->it_in.c_cflag = TTYDEF_CFLAG | CLOCAL;
		com->it_in.c_lflag = TTYDEF_LFLAG;
		com->lt_out.c_cflag = com->lt_in.c_cflag = CLOCAL;
	}
	termioschars(&com->it_in);
	com->it_in.c_ispeed = com->it_in.c_ospeed = comdefaultrate;
	com->it_out = com->it_in;

	/* attempt to determine UART type */
	printf("sio%d: type", unit);

#ifdef DSI_SOFT_MODEM
	if((inb(iobase+7) ^ inb(iobase+7)) & 0x80) {
	    printf(" Digicom Systems, Inc. SoftModem");
	    kdc_sio[unit].kdc_description =
	      "Serial port: Digicom Systems SoftModem";
	goto determined_type;
	}
#endif /* DSI_SOFT_MODEM */

#ifdef COM_MULTIPORT
	if (!COM_ISMULTIPORT(isdp))
#endif
	{
		u_char	scr;
		u_char	scr1;
		u_char	scr2;

		scr = inb(iobase + com_scr);
		outb(iobase + com_scr, 0xa5);
		scr1 = inb(iobase + com_scr);
		outb(iobase + com_scr, 0x5a);
		scr2 = inb(iobase + com_scr);
		outb(iobase + com_scr, scr);
		if (scr1 != 0xa5 || scr2 != 0x5a) {
			printf(" 8250");
			kdc_sio[unit].kdc_description =
			  "Serial port: National 8250 or compatible";
			goto determined_type;
		}
	}
	outb(iobase + com_fifo, FIFO_ENABLE | FIFO_TRIGGER_14);
	DELAY(100);
	switch (inb(com->int_id_port) & IIR_FIFO_MASK) {
	case FIFO_TRIGGER_1:
		printf(" 16450");
		kdc_sio[unit].kdc_description =
		  "Serial port: National 16450 or compatible";
		break;
	case FIFO_TRIGGER_4:
		printf(" 16450?");
		kdc_sio[unit].kdc_description =
		  "Serial port: maybe National 16450";
		break;
	case FIFO_TRIGGER_8:
		printf(" 16550?");
		kdc_sio[unit].kdc_description =
		  "Serial port: maybe National 16550";
		break;
	case FIFO_TRIGGER_14:
		printf(" 16550A");
		if (COM_NOFIFO(isdp)) {
			printf(" fifo disabled");
			kdc_sio[unit].kdc_description =
			  "Serial port: National 16550A, FIFO disabled";
		} else {
			com->hasfifo = TRUE;
			com->ftl_init = FIFO_TRIGGER_14;
			com->tx_fifo_size = 16;
			kdc_sio[unit].kdc_description =
			  "Serial port: National 16550A or compatible";
		}
		break;
	}
	outb(iobase + com_fifo, 0);
determined_type: ;

#ifdef COM_MULTIPORT
	if (COM_ISMULTIPORT(isdp)) {
		com->multiport = TRUE;
		printf(" (multiport");
		if (unit == COM_MPMASTER(isdp))
			printf(" master");
		printf(")");
		com->no_irq = find_isadev(isa_devtab_tty, &siodriver,
					  COM_MPMASTER(isdp))->id_irq == 0;
	 }
#endif /* COM_MULTIPORT */
	printf("\n");

	kdc_sio[unit].kdc_state = (unit == comconsole) ? DC_BUSY : DC_IDLE;

#ifdef KGDB
	if (kgdb_dev == makedev(commajor, unit)) {
		if (unit == comconsole)
			kgdb_dev = -1;	/* can't debug over console port */
		else {
			int	divisor;

			/*
			 * XXX now unfinished and broken.  Need to do
			 * something more like a full open().  There's no
			 * suitable interrupt handler so don't enable device
			 * interrupts.  Watch out for null tp's.
			 */
			outb(iobase + com_cfcr, CFCR_DLAB);
			divisor = ttspeedtab(kgdb_rate, comspeedtab);
			outb(iobase + com_dlbl, divisor & 0xFF);
			outb(iobase + com_dlbh, (u_int) divisor >> 8);
			outb(iobase + com_cfcr, CFCR_8BITS);
			outb(com->modem_ctl_port,
			     com->mcr_image |= MCR_DTR | MCR_RTS);

			if (kgdb_debug_init) {
				/*
				 * Print prefix of device name,
				 * let kgdb_connect print the rest.
				 */
				printf("sio%d: ", unit);
				kgdb_connect(1);
			} else
				printf("sio%d: kgdb enabled\n", unit);
		}
	}
#endif

	s = spltty();
	com_addr(unit) = com;
	splx(s);
	return (1);
}

int
sioopen(dev, flag, mode, p)
	dev_t		dev;
	int		flag;
	int		mode;
	struct proc	*p;
{
	struct com_s	*com;
	int		error;
	Port_t		iobase;
	int		mynor;
	int		s;
	struct tty	*tp;
	int		unit;

	mynor = minor(dev);
	unit = MINOR_TO_UNIT(mynor);
	if ((u_int) unit >= NSIO || (com = com_addr(unit)) == NULL)
		return (ENXIO);
	if (com->gone)
		return (ENXIO);
	if (mynor & CONTROL_MASK)
		return (0);
#if 0 /* XXX */
	tp = com->tp = sio_tty[unit] = ttymalloc(sio_tty[unit]);
#else
	tp = com->tp = &sio_tty[unit];
#endif
	s = spltty();
	/*
	 * We jump to this label after all non-interrupted sleeps to pick
	 * up any changes of the device state.
	 */
open_top:
	while (com->state & CS_DTR_OFF) {
		error = tsleep(&com->dtr_wait, TTIPRI | PCATCH, "siodtr", 0);
		if (com_addr(unit) == NULL)
			return (ENXIO);
		if (error != 0 || com->gone)
			goto out;
	}
	kdc_sio[unit].kdc_state = DC_BUSY;
	if (tp->t_state & TS_ISOPEN) {
		/*
		 * The device is open, so everything has been initialized.
		 * Handle conflicts.
		 */
		if (mynor & CALLOUT_MASK) {
			if (!com->active_out) {
				error = EBUSY;
				goto out;
			}
		} else {
			if (com->active_out) {
				if (flag & O_NONBLOCK) {
					error = EBUSY;
					goto out;
				}
				error =	tsleep(&com->active_out,
					       TTIPRI | PCATCH, "siobi", 0);
				if (com_addr(unit) == NULL)
					return (ENXIO);
				if (error != 0 || com->gone)
					goto out;
				goto open_top;
			}
		}
		if (tp->t_state & TS_XCLUDE && p->p_ucred->cr_uid != 0) {
			error = EBUSY;
			goto out;
		}
	} else {
		/*
		 * The device isn't open, so there are no conflicts.
		 * Initialize it.  Initialization is done twice in many
		 * cases: to preempt sleeping callin opens if we are
		 * callout, and to complete a callin open after DCD rises.
		 */
		tp->t_oproc = comstart;
		tp->t_param = comparam;
		tp->t_dev = dev;
		tp->t_termios = mynor & CALLOUT_MASK
				? com->it_out : com->it_in;
		(void)commctl(com, TIOCM_DTR | TIOCM_RTS, DMSET);
		com->ftl_max = com->ftl_init;
		com->poll = com->no_irq;
		com->poll_output = com->loses_outints;
		++com->wopeners;
		error = comparam(tp, &tp->t_termios);
		--com->wopeners;
		if (error != 0)
			goto out;
		/*
		 * XXX we should goto open_top if comparam() slept.
		 */
		ttsetwater(tp);
		iobase = com->iobase;
		if (com->hasfifo) {
			/*
			 * (Re)enable and drain fifos.
			 *
			 * Certain SMC chips cause problems if the fifos
			 * are enabled while input is ready.  Turn off the
			 * fifo if necessary to clear the input.  We test
			 * the input ready bit after enabling the fifos
			 * since we've already enabled them in comparam()
			 * and to handle races between enabling and fresh
			 * input.
			 */
			while (TRUE) {
				outb(iobase + com_fifo,
				     FIFO_RCV_RST | FIFO_XMT_RST
				     | FIFO_ENABLE | com->ftl);
				DELAY(100);
				if (!(inb(com->line_status_port) & LSR_RXRDY))
					break;
				outb(iobase + com_fifo, 0);
				DELAY(100);
				(void) inb(com->data_port);
			}
		}

		disable_intr();
		(void) inb(com->line_status_port);
		(void) inb(com->data_port);
		com->prev_modem_status = com->last_modem_status
		    = inb(com->modem_status_port);
		outb(iobase + com_ier, IER_ERXRDY | IER_ETXRDY | IER_ERLS
				       | IER_EMSC);
		enable_intr();
		/*
		 * Handle initial DCD.  Callout devices get a fake initial
		 * DCD (trapdoor DCD).  If we are callout, then any sleeping
		 * callin opens get woken up and resume sleeping on "siobi"
		 * instead of "siodcd".
		 */
		/*
		 * XXX `mynor & CALLOUT_MASK' should be
		 * `tp->t_cflag & (SOFT_CARRIER | TRAPDOOR_CARRIER) where
		 * TRAPDOOR_CARRIER is the default initial state for callout
		 * devices and SOFT_CARRIER is like CLOCAL except it hides
		 * the true carrier.
		 */
		if (com->prev_modem_status & MSR_DCD || mynor & CALLOUT_MASK)
			(*linesw[tp->t_line].l_modem)(tp, 1);
	}
	/*
	 * Wait for DCD if necessary.
	 */
	if (!(tp->t_state & TS_CARR_ON) && !(mynor & CALLOUT_MASK)
	    && !(tp->t_cflag & CLOCAL) && !(flag & O_NONBLOCK)) {
		++com->wopeners;
		error = tsleep(TSA_CARR_ON(tp), TTIPRI | PCATCH, "siodcd", 0);
		if (com_addr(unit) == NULL)
			return (ENXIO);
		--com->wopeners;
		if (error != 0 || com->gone)
			goto out;
		goto open_top;
	}
	error =	(*linesw[tp->t_line].l_open)(dev, tp);
	disc_optim(tp, &tp->t_termios, com);
	if (tp->t_state & TS_ISOPEN && mynor & CALLOUT_MASK)
		com->active_out = TRUE;
	siosettimeout();
out:
	splx(s);
	if (!(tp->t_state & TS_ISOPEN) && com->wopeners == 0)
		comhardclose(com);
	return (error);
}

int
sioclose(dev, flag, mode, p)
	dev_t		dev;
	int		flag;
	int		mode;
	struct proc	*p;
{
	struct com_s	*com;
	int		mynor;
	int		s;
	struct tty	*tp;

	mynor = minor(dev);
	if (mynor & CONTROL_MASK)
		return (0);
	com = com_addr(MINOR_TO_UNIT(mynor));
	tp = com->tp;
	s = spltty();
	(*linesw[tp->t_line].l_close)(tp, flag);
	disc_optim(tp, &tp->t_termios, com);
	siostop(tp, FREAD | FWRITE);
	comhardclose(com);
	ttyclose(tp);
	siosettimeout();
	splx(s);
	if (com->gone) {
		printf("sio%d: gone\n", com->unit);
		s = spltty();
		com_addr(com->unit) = 0;
		bzero(tp,sizeof *tp);
		bzero(com,sizeof *com);
		free(com,M_TTYS);
		splx(s);
	}
	return (0);
}

static void
comhardclose(com)
	struct com_s	*com;
{
	Port_t		iobase;
	int		s;
	struct tty	*tp;
	int		unit;

	unit = com->unit;
	iobase = com->iobase;
	s = spltty();
	com->poll = FALSE;
	com->poll_output = FALSE;
	com->do_timestamp = 0;
	outb(iobase + com_cfcr, com->cfcr_image &= ~CFCR_SBREAK);
#ifdef KGDB
	/* do not disable interrupts or hang up if debugging */
	if (kgdb_dev != makedev(commajor, unit))
#endif
	{
		outb(iobase + com_ier, 0);
		tp = com->tp;
		if (tp->t_cflag & HUPCL
		    /*
		     * XXX we will miss any carrier drop between here and the
		     * next open.  Perhaps we should watch DCD even when the
		     * port is closed; it is not sufficient to check it at
		     * the next open because it might go up and down while
		     * we're not watching.
		     */
		    || !com->active_out
		       && !(com->prev_modem_status & MSR_DCD)
		       && !(com->it_in.c_cflag & CLOCAL)
		    || !(tp->t_state & TS_ISOPEN)) {
			(void)commctl(com, TIOCM_DTR, DMBIC);
			if (com->dtr_wait != 0) {
				timeout(siodtrwakeup, com, com->dtr_wait);
				com->state |= CS_DTR_OFF;
			}
		}
	}
	if (com->hasfifo) {
		/*
		 * Disable fifos so that they are off after controlled
		 * reboots.  Some BIOSes fail to detect 16550s when the
		 * fifos are enabled.
		 */
		outb(iobase + com_fifo, 0);
	}
	com->active_out = FALSE;
	wakeup(&com->active_out);
	wakeup(TSA_CARR_ON(tp));	/* restart any wopeners */
	if (!(com->state & CS_DTR_OFF) && unit != comconsole)
		kdc_sio[unit].kdc_state = DC_IDLE;
	splx(s);
}

int
sioread(dev, uio, flag)
	dev_t		dev;
	struct uio	*uio;
	int		flag;
{
	int		mynor;
	int		unit;
	struct tty	*tp;

	mynor = minor(dev);
	if (mynor & CONTROL_MASK)
		return (ENODEV);
	unit = MINOR_TO_UNIT(mynor);
	if (com_addr(unit)->gone)
		return (ENODEV);
	tp = com_addr(unit)->tp;
	return ((*linesw[tp->t_line].l_read)(tp, uio, flag));
}

int
siowrite(dev, uio, flag)
	dev_t		dev;
	struct uio	*uio;
	int		flag;
{
	int		mynor;
	struct tty	*tp;
	int		unit;

	mynor = minor(dev);
	if (mynor & CONTROL_MASK)
		return (ENODEV);

	unit = MINOR_TO_UNIT(mynor);
	if (com_addr(unit)->gone)
		return (ENODEV);
	tp = com_addr(unit)->tp;
	/*
	 * (XXX) We disallow virtual consoles if the physical console is
	 * a serial port.  This is in case there is a display attached that
	 * is not the console.  In that situation we don't need/want the X
	 * server taking over the console.
	 */
	if (constty != NULL && unit == comconsole)
		constty = NULL;
	return ((*linesw[tp->t_line].l_write)(tp, uio, flag));
}

static void
siodtrwakeup(chan)
	void	*chan;
{
	struct com_s	*com;

	com = (struct com_s *)chan;
	com->state &= ~CS_DTR_OFF;
	if (com->unit != comconsole)
		kdc_sio[com->unit].kdc_state = DC_IDLE;
	wakeup(&com->dtr_wait);
}

/* Interrupt routine for timekeeping purposes */
void
siointrts(unit)
	int	unit;
{
	/*
	 * XXX microtime() reenables CPU interrupts.  We can't afford to
	 * be interrupted and don't want to slow down microtime(), so lock
	 * out interrupts in another way.
	 */
	outb(IO_ICU1 + 1, 0xff);
	microtime(&intr_timestamp);
	disable_intr();
	outb(IO_ICU1 + 1, imen);

	siointr(unit);
}

void
siointr(unit)
	int	unit;
{
#ifndef COM_MULTIPORT
	siointr1(com_addr(unit));
#else /* COM_MULTIPORT */
	struct com_s    *com;
	bool_t		possibly_more_intrs;

	/*
	 * Loop until there is no activity on any port.  This is necessary
	 * to get an interrupt edge more than to avoid another interrupt.
	 * If the IRQ signal is just an OR of the IRQ signals from several
	 * devices, then the edge from one may be lost because another is
	 * on.
	 */
	do {
		possibly_more_intrs = FALSE;
		for (unit = 0; unit < NSIO; ++unit) {
			com = com_addr(unit);
			if (com != NULL 
			    && !com->gone
			    && (inb(com->int_id_port) & IIR_IMASK)
			       != IIR_NOPEND) {
				siointr1(com);
				possibly_more_intrs = TRUE;
			}
		}
	} while (possibly_more_intrs);
#endif /* COM_MULTIPORT */
}

static void
siointr1(com)
	struct com_s	*com;
{
	u_char	line_status;
	u_char	modem_status;
	u_char	*ioptr;
	u_char	recv_data;

	if (com->do_timestamp)
		/* XXX a little bloat here... */
		com->timestamp = intr_timestamp;
	while (TRUE) {
		line_status = inb(com->line_status_port);

		/* input event? (check first to help avoid overruns) */
		while (line_status & LSR_RCV_MASK) {
			/* break/unnattached error bits or real input? */
			if (!(line_status & LSR_RXRDY))
				recv_data = 0;
			else
				recv_data = inb(com->data_port);
			if (line_status & (LSR_PE|LSR_FE|LSR_BI)) {
#ifdef DDB
#ifdef BREAK_TO_DEBUGGER
				if (line_status & LSR_BI
				    && com->unit == comconsole)	{
					Debugger("serial console break");
					goto cont;
				}
#endif
#endif
				/*
				  Don't store PE if IGNPAR and BI if IGNBRK,
				  this hack allows "raw" tty optimization
				  works even if IGN* is set.
				*/
				if (   com->tp == NULL
				    || !(com->tp->t_state & TS_ISOPEN)
				    || (line_status & (LSR_PE|LSR_FE))
				    &&  (com->tp->t_iflag & IGNPAR)
				    || (line_status & LSR_BI)
				    &&  (com->tp->t_iflag & IGNBRK))
					goto cont;
				if (   (line_status & (LSR_PE|LSR_FE))
				    && (com->tp->t_state & TS_CAN_BYPASS_L_RINT)
				    && ((line_status & LSR_FE)
				    ||  (line_status & LSR_PE)
				    &&  (com->tp->t_iflag & INPCK)))
					recv_data = 0;
			}
			++com->bytes_in;
			if (com->hotchar != 0 && recv_data == com->hotchar)
				setsofttty();
#ifdef KGDB
			/* trap into kgdb? (XXX - needs testing and optim) */
			if (recv_data == FRAME_END
			    && (   com->tp == NULL
				|| !(com->tp->t_state & TS_ISOPEN))
			    && kgdb_dev == makedev(commajor, unit)) {
				kgdb_connect(0);
				continue;
			}
#endif /* KGDB */
			ioptr = com->iptr;
			if (ioptr >= com->ibufend)
				CE_RECORD(com, CE_INTERRUPT_BUF_OVERFLOW);
			else {
				++com_events;
				schedsofttty();
#if 0 /* for testing input latency vs efficiency */
if (com->iptr - com->ibuf == 8)
	setsofttty();
#endif
				ioptr[0] = recv_data;
				ioptr[CE_INPUT_OFFSET] = line_status;
				com->iptr = ++ioptr;
				if (ioptr == com->ihighwater
				    && com->state & CS_RTS_IFLOW)
					outb(com->modem_ctl_port,
					     com->mcr_image &= ~MCR_RTS);
				if (line_status & LSR_OE)
					CE_RECORD(com, CE_OVERRUN);
			}
cont:
			/*
			 * "& 0x7F" is to avoid the gcc-1.40 generating a slow
			 * jump from the top of the loop to here
			 */
			line_status = inb(com->line_status_port) & 0x7F;
		}

		/* modem status change? (always check before doing output) */
		modem_status = inb(com->modem_status_port);
		if (modem_status != com->last_modem_status) {
			/*
			 * Schedule high level to handle DCD changes.  Note
			 * that we don't use the delta bits anywhere.  Some
			 * UARTs mess them up, and it's easy to remember the
			 * previous bits and calculate the delta.
			 */
			com->last_modem_status = modem_status;
			if (!(com->state & CS_CHECKMSR)) {
				com_events += LOTS_OF_EVENTS;
				com->state |= CS_CHECKMSR;
				setsofttty();
			}

			/* handle CTS change immediately for crisp flow ctl */
			if (com->state & CS_CTS_OFLOW) {
				if (modem_status & MSR_CTS)
					com->state |= CS_ODEVREADY;
				else
					com->state &= ~CS_ODEVREADY;
			}
		}

		/* output queued and everything ready? */
		if (line_status & LSR_TXRDY
		    && com->state >= (CS_BUSY | CS_TTGO | CS_ODEVREADY)) {
			ioptr = com->obufq.l_head;
			if (com->tx_fifo_size > 1) {
				u_int	ocount;

				ocount = com->obufq.l_tail - ioptr;
				if (ocount > com->tx_fifo_size)
					ocount = com->tx_fifo_size;
				com->bytes_out += ocount;
				do
					outb(com->data_port, *ioptr++);
				while (--ocount != 0);
			} else {
				outb(com->data_port, *ioptr++);
				++com->bytes_out;
			}
			com->obufq.l_head = ioptr;
			if (ioptr >= com->obufq.l_tail) {
				struct lbq	*qp;

				qp = com->obufq.l_next;
				qp->l_queued = FALSE;
				qp = qp->l_next;
				if (qp != NULL) {
					com->obufq.l_head = qp->l_head;
					com->obufq.l_tail = qp->l_tail;
					com->obufq.l_next = qp;
				} else {
					/* output just completed */
					com->state &= ~CS_BUSY;
				}
				if (!(com->state & CS_ODONE)) {
					com_events += LOTS_OF_EVENTS;
					com->state |= CS_ODONE;
					setsofttty();	/* handle at high level ASAP */
				}
			}
		}

		/* finished? */
#ifndef COM_MULTIPORT
		if ((inb(com->int_id_port) & IIR_IMASK) == IIR_NOPEND)
#endif /* COM_MULTIPORT */
			return;
	}
}

int
sioioctl(dev, cmd, data, flag, p)
	dev_t		dev;
	int		cmd;
	caddr_t		data;
	int		flag;
	struct proc	*p;
{
	struct com_s	*com;
	int		error;
	Port_t		iobase;
	int		mynor;
	int		s;
	struct tty	*tp;
#if defined(COMPAT_43) || defined(COMPAT_SUNOS)
	int		oldcmd;
	struct termios	term;
#endif

	mynor = minor(dev);
	com = com_addr(MINOR_TO_UNIT(mynor));
	if (com->gone)
		return (ENODEV);
	iobase = com->iobase;
	if (mynor & CONTROL_MASK) {
		struct termios	*ct;

		switch (mynor & CONTROL_MASK) {
		case CONTROL_INIT_STATE:
			ct = mynor & CALLOUT_MASK ? &com->it_out : &com->it_in;
			break;
		case CONTROL_LOCK_STATE:
			ct = mynor & CALLOUT_MASK ? &com->lt_out : &com->lt_in;
			break;
		default:
			return (ENODEV);	/* /dev/nodev */
		}
		switch (cmd) {
		case TIOCSETA:
			error = suser(p->p_ucred, &p->p_acflag);
			if (error != 0)
				return (error);
			*ct = *(struct termios *)data;
			return (0);
		case TIOCGETA:
			*(struct termios *)data = *ct;
			return (0);
		case TIOCGETD:
			*(int *)data = TTYDISC;
			return (0);
		case TIOCGWINSZ:
			bzero(data, sizeof(struct winsize));
			return (0);
#ifdef DSI_SOFT_MODEM
		/*
		 * Download micro-code to Digicom modem.
		 */
		case TIOCDSIMICROCODE:
			{
			u_long l;
			u_char *p,*pi;

			pi = (u_char*)(*(caddr_t*)data);
			error = copyin(pi,&l,sizeof l);
			if(error)
				{return error;};
			pi += sizeof l;

			p = malloc(l,M_TEMP,M_NOWAIT);
			if(!p)
				{return ENOBUFS;}
			error = copyin(pi,p,l);
			if(error)
				{free(p,M_TEMP); return error;};
			if(error = LoadSoftModem(
			    MINOR_TO_UNIT(mynor),iobase,l,p))
				{free(p,M_TEMP); return error;}
			free(p,M_TEMP);
			return(0);
			}
#endif /* DSI_SOFT_MODEM */
		default:
			return (ENOTTY);
		}
	}
	tp = com->tp;
#if defined(COMPAT_43) || defined(COMPAT_SUNOS)
	term = tp->t_termios;
	oldcmd = cmd;
	error = ttsetcompat(tp, &cmd, data, &term);
	if (error != 0)
		return (error);
	if (cmd != oldcmd)
		data = (caddr_t)&term;
#endif
	if (cmd == TIOCSETA || cmd == TIOCSETAW || cmd == TIOCSETAF) {
		int	cc;
		struct termios *dt = (struct termios *)data;
		struct termios *lt = mynor & CALLOUT_MASK
				     ? &com->lt_out : &com->lt_in;

		dt->c_iflag = (tp->t_iflag & lt->c_iflag)
			      | (dt->c_iflag & ~lt->c_iflag);
		dt->c_oflag = (tp->t_oflag & lt->c_oflag)
			      | (dt->c_oflag & ~lt->c_oflag);
		dt->c_cflag = (tp->t_cflag & lt->c_cflag)
			      | (dt->c_cflag & ~lt->c_cflag);
		dt->c_lflag = (tp->t_lflag & lt->c_lflag)
			      | (dt->c_lflag & ~lt->c_lflag);
		for (cc = 0; cc < NCCS; ++cc)
			if (lt->c_cc[cc] != 0)
				dt->c_cc[cc] = tp->t_cc[cc];
		if (lt->c_ispeed != 0)
			dt->c_ispeed = tp->t_ispeed;
		if (lt->c_ospeed != 0)
			dt->c_ospeed = tp->t_ospeed;
	}
	error = (*linesw[tp->t_line].l_ioctl)(tp, cmd, data, flag, p);
	if (error >= 0)
		return (error);
	s = spltty();
	error = ttioctl(tp, cmd, data, flag);
	disc_optim(tp, &tp->t_termios, com);
	if (error >= 0) {
		splx(s);
		return (error);
	}
	switch (cmd) {
	case TIOCSBRK:
		outb(iobase + com_cfcr, com->cfcr_image |= CFCR_SBREAK);
		break;
	case TIOCCBRK:
		outb(iobase + com_cfcr, com->cfcr_image &= ~CFCR_SBREAK);
		break;
	case TIOCSDTR:
		(void)commctl(com, TIOCM_DTR, DMBIS);
		break;
	case TIOCCDTR:
		(void)commctl(com, TIOCM_DTR, DMBIC);
		break;
	case TIOCMSET:
		(void)commctl(com, *(int *)data, DMSET);
		break;
	case TIOCMBIS:
		(void)commctl(com, *(int *)data, DMBIS);
		break;
	case TIOCMBIC:
		(void)commctl(com, *(int *)data, DMBIC);
		break;
	case TIOCMGET:
		*(int *)data = commctl(com, 0, DMGET);
		break;
	case TIOCMSDTRWAIT:
		/* must be root since the wait applies to following logins */
		error = suser(p->p_ucred, &p->p_acflag);
		if (error != 0) {
			splx(s);
			return (error);
		}
		com->dtr_wait = *(int *)data * hz / 100;
		break;
	case TIOCMGDTRWAIT:
		*(int *)data = com->dtr_wait * 100 / hz;
		break;
	case TIOCTIMESTAMP:
		com->do_timestamp = TRUE;
		*(struct timeval *)data = com->timestamp;
		break;
	default:
		splx(s);
		return (ENOTTY);
	}
	splx(s);
	return (0);
}

void
siopoll()
{
	int		unit;

	if (com_events == 0)
		return;
repeat:
	for (unit = 0; unit < NSIO; ++unit) {
		u_char		*buf;
		struct com_s	*com;
		u_char		*ibuf;
		int		incc;
		struct tty	*tp;

		com = com_addr(unit);
		if (com == NULL)
			continue;
		if (com->gone)
			continue;
		tp = com->tp;
		if (tp == NULL) {
			/*
			 * XXX forget any events related to closed devices
			 * (actually never opened devices) so that we don't
			 * loop.
			 */
			disable_intr();
			incc = com->iptr - com->ibuf;
			com->iptr = com->ibuf;
			if (com->state & CS_CHECKMSR) {
				incc += LOTS_OF_EVENTS;
				com->state &= ~CS_CHECKMSR;
			}
			com_events -= incc;
			enable_intr();
			if (incc != 0)
				log(LOG_DEBUG,
				    "sio%d: %d events for device with no tp\n",
				    unit, incc);
			continue;
		}

		/* switch the role of the low-level input buffers */
		if (com->iptr == (ibuf = com->ibuf)) {
			buf = NULL;     /* not used, but compiler can't tell */
			incc = 0;
		} else {
			buf = ibuf;
			disable_intr();
			incc = com->iptr - buf;
			com_events -= incc;
			if (ibuf == com->ibuf1)
				ibuf = com->ibuf2;
			else
				ibuf = com->ibuf1;
			com->ibufend = ibuf + RS_IBUFSIZE;
			com->ihighwater = ibuf + RS_IHIGHWATER;
			com->iptr = ibuf;

			/*
			 * There is now room for another low-level buffer full
			 * of input, so enable RTS if it is now disabled and
			 * there is room in the high-level buffer.
			 */
			/*
			 * XXX this used not to look at CS_RTS_IFLOW.  The
			 * change is to allow full control of MCR_RTS via
			 * ioctls after turning CS_RTS_IFLOW off.  Check
			 * for races.  We shouldn't allow the ioctls while
			 * CS_RTS_IFLOW is on.
			 */
			if ((com->state & CS_RTS_IFLOW)
			    && !(com->mcr_image & MCR_RTS)
			    && !(tp->t_state & TS_TBLOCK))
				outb(com->modem_ctl_port,
				     com->mcr_image |= MCR_RTS);
			enable_intr();
			com->ibuf = ibuf;
		}

		if (com->state & CS_CHECKMSR) {
			u_char	delta_modem_status;

			disable_intr();
			delta_modem_status = com->last_modem_status
					     ^ com->prev_modem_status;
			com->prev_modem_status = com->last_modem_status;
			com_events -= LOTS_OF_EVENTS;
			com->state &= ~CS_CHECKMSR;
			enable_intr();
			if (delta_modem_status & MSR_DCD)
				(*linesw[tp->t_line].l_modem)
					(tp, com->prev_modem_status & MSR_DCD);
		}
		if (com->state & CS_ODONE) {
			disable_intr();
			com_events -= LOTS_OF_EVENTS;
			com->state &= ~CS_ODONE;
			if (!(com->state & CS_BUSY))
				com->tp->t_state &= ~TS_BUSY;
			enable_intr();
			(*linesw[tp->t_line].l_start)(tp);
		}
		if (incc <= 0 || !(tp->t_state & TS_ISOPEN))
			continue;
		/*
		 * Avoid the grotesquely inefficient lineswitch routine
		 * (ttyinput) in "raw" mode.  It usually takes about 450
		 * instructions (that's without canonical processing or echo!).
		 * slinput is reasonably fast (usually 40 instructions plus
		 * call overhead).
		 */
		if (tp->t_state & TS_CAN_BYPASS_L_RINT) {
			if (tp->t_rawq.c_cc + incc >= RB_I_HIGH_WATER
			    && (com->state & CS_RTS_IFLOW
				|| tp->t_iflag & IXOFF)
			    && !(tp->t_state & TS_TBLOCK))
				ttyblock(tp);
			tk_nin += incc;
			tk_rawcc += incc;
			tp->t_rawcc += incc;
			com->delta_error_counts[CE_TTY_BUF_OVERFLOW]
				+= b_to_q((char *)buf, incc, &tp->t_rawq);
			ttwakeup(tp);
			if (tp->t_state & TS_TTSTOP
			    && (tp->t_iflag & IXANY
				|| tp->t_cc[VSTART] == tp->t_cc[VSTOP])) {
				tp->t_state &= ~TS_TTSTOP;
				tp->t_lflag &= ~FLUSHO;
				comstart(tp);
			}
		} else {
			do {
				u_char	line_status;
				int	recv_data;

				line_status = (u_char) buf[CE_INPUT_OFFSET];
				recv_data = (u_char) *buf++;
				if (line_status
				    & (LSR_BI | LSR_FE | LSR_OE | LSR_PE)) {
					if (line_status & LSR_BI)
						recv_data |= TTY_BI;
					if (line_status & LSR_FE)
						recv_data |= TTY_FE;
					if (line_status & LSR_OE)
						recv_data |= TTY_OE;
					if (line_status & LSR_PE)
						recv_data |= TTY_PE;
				}
				(*linesw[tp->t_line].l_rint)(recv_data, tp);
			} while (--incc > 0);
		}
		if (com_events == 0)
			break;
	}
	if (com_events >= LOTS_OF_EVENTS)
		goto repeat;
}

static int
comparam(tp, t)
	struct tty	*tp;
	struct termios	*t;
{
	u_int		cfcr;
	int		cflag;
	struct com_s	*com;
	int		divisor;
	int		error;
	Port_t		iobase;
	int		s;
	int		unit;
	int		txtimeout;

	/* do historical conversions */
	if (t->c_ispeed == 0)
		t->c_ispeed = t->c_ospeed;

	/* check requested parameters */
	divisor = ttspeedtab(t->c_ospeed, comspeedtab);
	if (divisor < 0 || divisor > 0 && t->c_ispeed != t->c_ospeed)
		return (EINVAL);

	/* parameters are OK, convert them to the com struct and the device */
	unit = DEV_TO_UNIT(tp->t_dev);
	com = com_addr(unit);
	iobase = com->iobase;
	s = spltty();
	if (divisor == 0)
		(void)commctl(com, TIOCM_DTR, DMBIC);	/* hang up line */
	else
		(void)commctl(com, TIOCM_DTR, DMBIS);
	cflag = t->c_cflag;
	switch (cflag & CSIZE) {
	case CS5:
		cfcr = CFCR_5BITS;
		break;
	case CS6:
		cfcr = CFCR_6BITS;
		break;
	case CS7:
		cfcr = CFCR_7BITS;
		break;
	default:
		cfcr = CFCR_8BITS;
		break;
	}
	if (cflag & PARENB) {
		cfcr |= CFCR_PENAB;
		if (!(cflag & PARODD))
			cfcr |= CFCR_PEVEN;
	}
	if (cflag & CSTOPB)
		cfcr |= CFCR_STOPB;

	if (com->hasfifo) {
		/*
		 * Use a fifo trigger level low enough so that the input
		 * latency from the fifo is less than about 16 msec and
		 * the total latency is less than about 30 msec.  These
		 * latencies are reasonable for humans.  Serial comms
		 * protocols shouldn't expect anything better since modem
		 * latencies are larger.
		 */
		com->ftl = t->c_ospeed <= 4800
			   ? FIFO_TRIGGER_1 : FIFO_TRIGGER_14;
		if (com->ftl > com->ftl_max)
			com->ftl = com->ftl_max;
		outb(iobase + com_fifo, FIFO_ENABLE | com->ftl);
	}

	/*
	 * Some UARTs lock up if the divisor latch registers are selected
	 * while the UART is doing output (they refuse to transmit anything
	 * more until given a hard reset).  Fix this by stopping filling
	 * the device buffers and waiting for them to drain.  Reading the
	 * line status port outside of siointr1() might lose some receiver
	 * error bits, but that is acceptable here.
	 */
	disable_intr();
retry:
	com->state &= ~CS_TTGO;
	txtimeout = tp->t_timeout;
	enable_intr();
	while ((inb(com->line_status_port) & (LSR_TSRE | LSR_TXRDY))
	       != (LSR_TSRE | LSR_TXRDY)) {
		tp->t_state |= TS_SO_OCOMPLETE;
		error = ttysleep(tp, TSA_OCOMPLETE(tp), TTIPRI | PCATCH,
				 "siotx", hz / 100);
		if (   txtimeout != 0
		    && (!error || error	== EAGAIN)
		    && (txtimeout -= hz	/ 100) <= 0
		   )
			error = EIO;
		if (com->gone)
			error = ENODEV;
		if (error != 0 && error != EAGAIN) {
			if (!(tp->t_state & TS_TTSTOP)) {
				disable_intr();
				com->state |= CS_TTGO;
				enable_intr();
			}
			splx(s);
			return (error);
		}
	}

	disable_intr();		/* very important while com_data is hidden */

	/*
	 * XXX - clearing CS_TTGO is not sufficient to stop further output,
	 * because siopoll() calls comstart() which usually sets it again
	 * because TS_TTSTOP is clear.  Setting TS_TTSTOP would not be
	 * sufficient, for similar reasons.
	 */
	if ((inb(com->line_status_port) & (LSR_TSRE | LSR_TXRDY))
	    != (LSR_TSRE | LSR_TXRDY))
		goto retry;

	if (divisor != 0) {
		outb(iobase + com_cfcr, cfcr | CFCR_DLAB);
		outb(iobase + com_dlbl, divisor & 0xFF);
		outb(iobase + com_dlbh, (u_int) divisor >> 8);
	}
	outb(iobase + com_cfcr, com->cfcr_image = cfcr);
	if (!(tp->t_state & TS_TTSTOP))
		com->state |= CS_TTGO;
	if (cflag & CRTS_IFLOW)
		com->state |= CS_RTS_IFLOW;	/* XXX - secondary changes? */
	else
		com->state &= ~CS_RTS_IFLOW;

	/*
	 * Set up state to handle output flow control.
	 * XXX - worth handling MDMBUF (DCD) flow control at the lowest level?
	 * Now has 10+ msec latency, while CTS flow has 50- usec latency.
	 */
	com->state |= CS_ODEVREADY;
	com->state &= ~CS_CTS_OFLOW;
	if (cflag & CCTS_OFLOW) {
		com->state |= CS_CTS_OFLOW;
		if (!(com->last_modem_status & MSR_CTS))
			com->state &= ~CS_ODEVREADY;
	}
	/* XXX shouldn't call functions while intrs are disabled. */
	disc_optim(tp, t, com);
	/*
	 * Recover from fiddling with CS_TTGO.  We used to call siointr1()
	 * unconditionally, but that defeated the careful discarding of
	 * stale input in sioopen().
	 */
	if (com->state >= (CS_BUSY | CS_TTGO))
		siointr1(com);

	enable_intr();
	splx(s);
	return (0);
}

static void
comstart(tp)
	struct tty	*tp;
{
	struct com_s	*com;
	int		s;
	int		unit;

	unit = DEV_TO_UNIT(tp->t_dev);
	com = com_addr(unit);
	s = spltty();
	disable_intr();
	if (tp->t_state & TS_TTSTOP)
		com->state &= ~CS_TTGO;
	else
		com->state |= CS_TTGO;
	if (tp->t_state & TS_TBLOCK) {
		if (com->mcr_image & MCR_RTS && com->state & CS_RTS_IFLOW)
			outb(com->modem_ctl_port, com->mcr_image &= ~MCR_RTS);
	} else {
		/*
		 * XXX don't raise MCR_RTS if CTS_RTS_IFLOW is off.  Set it
		 * appropriately in comparam() if RTS-flow is being changed.
		 * Check for races.
		 */
		if (!(com->mcr_image & MCR_RTS) && com->iptr < com->ihighwater)
			outb(com->modem_ctl_port, com->mcr_image |= MCR_RTS);
	}
	enable_intr();
	if (tp->t_state & (TS_TIMEOUT | TS_TTSTOP)) {
		splx(s);
		return;
	}
	if (tp->t_outq.c_cc != 0) {
		struct lbq	*qp;
		struct lbq	*next;

		if (!com->obufs[0].l_queued) {
			com->obufs[0].l_tail
			    = com->obuf1 + q_to_b(&tp->t_outq, com->obuf1,
						  sizeof com->obuf1);
			com->obufs[0].l_next = NULL;
			com->obufs[0].l_queued = TRUE;
			disable_intr();
			if (com->state & CS_BUSY) {
				qp = com->obufq.l_next;
				while ((next = qp->l_next) != NULL)
					qp = next;
				qp->l_next = &com->obufs[0];
			} else {
				com->obufq.l_head = com->obufs[0].l_head;
				com->obufq.l_tail = com->obufs[0].l_tail;
				com->obufq.l_next = &com->obufs[0];
				com->state |= CS_BUSY;
			}
			enable_intr();
		}
		if (tp->t_outq.c_cc != 0 && !com->obufs[1].l_queued) {
			com->obufs[1].l_tail
			    = com->obuf2 + q_to_b(&tp->t_outq, com->obuf2,
						  sizeof com->obuf2);
			com->obufs[1].l_next = NULL;
			com->obufs[1].l_queued = TRUE;
			disable_intr();
			if (com->state & CS_BUSY) {
				qp = com->obufq.l_next;
				while ((next = qp->l_next) != NULL)
					qp = next;
				qp->l_next = &com->obufs[1];
			} else {
				com->obufq.l_head = com->obufs[1].l_head;
				com->obufq.l_tail = com->obufs[1].l_tail;
				com->obufq.l_next = &com->obufs[1];
				com->state |= CS_BUSY;
			}
			enable_intr();
		}
		tp->t_state |= TS_BUSY;
	}
	disable_intr();
	if (com->state >= (CS_BUSY | CS_TTGO))
		siointr1(com);	/* fake interrupt to start output */
	enable_intr();
	ttwwakeup(tp);
	splx(s);
}

void
siostop(tp, rw)
	struct tty	*tp;
	int		rw;
{
	struct com_s	*com;

	com = com_addr(DEV_TO_UNIT(tp->t_dev));
	if (com->gone)
		return;
	disable_intr();
	if (rw & FWRITE) {
		com->obufs[0].l_queued = FALSE;
		com->obufs[1].l_queued = FALSE;
		if (com->state & CS_ODONE)
			com_events -= LOTS_OF_EVENTS;
		com->state &= ~(CS_ODONE | CS_BUSY);
		com->tp->t_state &= ~TS_BUSY;
	}
	if (rw & FREAD) {
		com_events -= (com->iptr - com->ibuf);
		com->iptr = com->ibuf;
	}
	enable_intr();
	comstart(tp);

	/* XXX should clear h/w fifos too. */
}

struct tty *
siodevtotty(dev)
	dev_t	dev;
{
	int	mynor;
	int	unit;

	mynor = minor(dev);
	if (mynor & CONTROL_MASK)
		return (NULL);
	unit = MINOR_TO_UNIT(mynor);
	if ((u_int) unit >= NSIO)
		return (NULL);
	return (&sio_tty[unit]);
}

static int
commctl(com, bits, how)
	struct com_s	*com;
	int		bits;
	int		how;
{
	int	mcr;
	int	msr;

	if (how == DMGET) {
		bits = TIOCM_LE;	/* XXX - always enabled while open */
		mcr = com->mcr_image;
		if (mcr & MCR_DTR)
			bits |= TIOCM_DTR;
		if (mcr & MCR_RTS)
			bits |= TIOCM_RTS;
		msr = com->prev_modem_status;
		if (msr & MSR_CTS)
			bits |= TIOCM_CTS;
		if (msr & MSR_DCD)
			bits |= TIOCM_CD;
		if (msr & MSR_DSR)
			bits |= TIOCM_DSR;
		/*
		 * XXX - MSR_RI is naturally volatile, and we make MSR_TERI
		 * more volatile by reading the modem status a lot.  Perhaps
		 * we should latch both bits until the status is read here.
		 */
		if (msr & (MSR_RI | MSR_TERI))
			bits |= TIOCM_RI;
		return (bits);
	}
	mcr = 0;
	if (bits & TIOCM_DTR)
		mcr |= MCR_DTR;
	if (bits & TIOCM_RTS)
		mcr |= MCR_RTS;
	if (com->gone)
		return(0);
	disable_intr();
	switch (how) {
	case DMSET:
		outb(com->modem_ctl_port,
		     com->mcr_image = mcr | (com->mcr_image & MCR_IENABLE));
		break;
	case DMBIS:
		outb(com->modem_ctl_port, com->mcr_image |= mcr);
		break;
	case DMBIC:
		outb(com->modem_ctl_port, com->mcr_image &= ~mcr);
		break;
	}
	enable_intr();
	return (0);
}

static void
siosettimeout()
{
	struct com_s	*com;
	bool_t		someopen;
	int		unit;

	/*
	 * Set our timeout period to 1 second if no polled devices are open.
	 * Otherwise set it to max(1/200, 1/hz).
	 * Enable timeouts iff some device is open.
	 */
	untimeout(comwakeup, (void *)NULL);
	sio_timeout = hz;
	someopen = FALSE;
	for (unit = 0; unit < NSIO; ++unit) {
		com = com_addr(unit);
		if (com != NULL && com->tp != NULL
		    && com->tp->t_state & TS_ISOPEN && !com->gone) {
			someopen = TRUE;
			if (com->poll || com->poll_output) {
				sio_timeout = hz > 200 ? hz / 200 : 1;
				break;
			}
		}
	}
	if (someopen) {
		sio_timeouts_until_log = hz / sio_timeout;
		timeout(comwakeup, (void *)NULL, sio_timeout);
	} else {
		/* Flush error messages, if any. */
		sio_timeouts_until_log = 1;
		comwakeup((void *)NULL);
		untimeout(comwakeup, (void *)NULL);
	}
}

static void
comwakeup(chan)
	void	*chan;
{
	struct com_s	*com;
	int		unit;

	timeout(comwakeup, (void *)NULL, sio_timeout);

	/*
	 * Recover from lost output interrupts.
	 * Poll any lines that don't use interrupts.
	 */
	for (unit = 0; unit < NSIO; ++unit) {
		com = com_addr(unit);
		if (com != NULL && !com->gone
		    && (com->state >= (CS_BUSY | CS_TTGO) || com->poll)) {
			disable_intr();
			siointr1(com);
			enable_intr();
		}
	}

	/*
	 * Check for and log errors, but not too often.
	 */
	if (--sio_timeouts_until_log > 0)
		return;
	sio_timeouts_until_log = hz / sio_timeout;
	for (unit = 0; unit < NSIO; ++unit) {
		int	errnum;

		com = com_addr(unit);
		if (com == NULL)
			continue;
		if (com->gone)
			continue;
		for (errnum = 0; errnum < CE_NTYPES; ++errnum) {
			u_int	delta;
			u_long	total;

			disable_intr();
			delta = com->delta_error_counts[errnum];
			com->delta_error_counts[errnum] = 0;
			enable_intr();
			if (delta == 0)
				continue;
			total = com->error_counts[errnum] += delta;
			log(LOG_ERR, "sio%d: %u more %s%s (total %lu)\n",
			    unit, delta, error_desc[errnum],
			    delta == 1 ? "" : "s", total);
#if 0
			/*
			 * XXX if we resurrect this then we should move
			 * the dropping of the ftl to somewhere with less
			 * latency.
			 */
			if (errnum == CE_OVERRUN && com->hasfifo
			    && com->ftl > FIFO_TRIGGER_1) {
				static	u_char	ftl_in_bytes[] =
					{ 1, 4, 8, 14, };

				com->ftl_init = FIFO_TRIGGER_8;
#define	FIFO_TRIGGER_DELTA	FIFO_TRIGGER_4
				com->ftl_max =
				com->ftl -= FIFO_TRIGGER_DELTA;
				outb(com->iobase + com_fifo,
				     FIFO_ENABLE | com->ftl);
				log(LOG_DEBUG,
				    "sio%d: reduced fifo trigger level to %d\n",
				    unit,
				    ftl_in_bytes[com->ftl
						 / FIFO_TRIGGER_DELTA]);
			}
#endif
		}
	}
}

static void
disc_optim(tp, t, com)
	struct tty	*tp;
	struct termios	*t;
	struct com_s	*com;
{
	if (!(t->c_iflag & (ICRNL | IGNCR | IMAXBEL | INLCR | ISTRIP | IXON))
	    && (!(t->c_iflag & BRKINT) || (t->c_iflag & IGNBRK))
	    && (!(t->c_iflag & PARMRK)
		|| (t->c_iflag & (IGNPAR | IGNBRK)) == (IGNPAR | IGNBRK))
	    && !(t->c_lflag & (ECHO | ICANON | IEXTEN | ISIG | PENDIN))
	    && linesw[tp->t_line].l_rint == ttyinput)
		tp->t_state |= TS_CAN_BYPASS_L_RINT;
	else
		tp->t_state &= ~TS_CAN_BYPASS_L_RINT;
	/*
	 * Prepare to reduce input latency for packet
	 * discplines with a end of packet character.
	 */
	if (tp->t_line == SLIPDISC)
		com->hotchar = 0xc0;
	else if (tp->t_line == PPPDISC)
		com->hotchar = 0x7e;
	else
		com->hotchar = 0;
}

/*
 * Following are all routines needed for SIO to act as console
 */
#include <machine/cons.h>

struct siocnstate {
	u_char	dlbl;
	u_char	dlbh;
	u_char	ier;
	u_char	cfcr;
	u_char	mcr;
};

static	Port_t	siocniobase;

static void siocnclose	__P((struct siocnstate *sp));
static void siocnopen	__P((struct siocnstate *sp));
static void siocntxwait	__P((void));

static void
siocntxwait()
{
	int	timo;

	/*
	 * Wait for any pending transmission to finish.  Required to avoid
	 * the UART lockup bug when the speed is changed, and for normal
	 * transmits.
	 */
	timo = 100000;
	while ((inb(siocniobase + com_lsr) & (LSR_TSRE | LSR_TXRDY))
	       != (LSR_TSRE | LSR_TXRDY) && --timo != 0)
		;
}

static void
siocnopen(sp)
	struct siocnstate	*sp;
{
	int	divisor;
	Port_t	iobase;

	/*
	 * Save all the device control registers except the fifo register
	 * and set our default ones (cs8 -parenb speed=comdefaultrate).
	 * We can't save the fifo register since it is read-only.
	 */
	iobase = siocniobase;
	sp->ier = inb(iobase + com_ier);
	outb(iobase + com_ier, 0);	/* spltty() doesn't stop siointr() */
	siocntxwait();
	sp->cfcr = inb(iobase + com_cfcr);
	outb(iobase + com_cfcr, CFCR_DLAB);
	sp->dlbl = inb(iobase + com_dlbl);
	sp->dlbh = inb(iobase + com_dlbh);
	divisor = ttspeedtab(comdefaultrate, comspeedtab);
	outb(iobase + com_dlbl, divisor & 0xFF);
	outb(iobase + com_dlbh, (u_int) divisor >> 8);
	outb(iobase + com_cfcr, CFCR_8BITS);
	sp->mcr = inb(iobase + com_mcr);
	/*
	 * We don't want interrupts, but must be careful not to "disable"
	 * them by clearing the MCR_IENABLE bit, since that might cause
	 * an interrupt by floating the IRQ line.
	 */
	outb(iobase + com_mcr, (sp->mcr & MCR_IENABLE) | MCR_DTR | MCR_RTS);
}

static void
siocnclose(sp)
	struct siocnstate	*sp;
{
	Port_t	iobase;

	/*
	 * Restore the device control registers.
	 */
	siocntxwait();
	iobase = siocniobase;
	outb(iobase + com_cfcr, CFCR_DLAB);
	outb(iobase + com_dlbl, sp->dlbl);
	outb(iobase + com_dlbh, sp->dlbh);
	outb(iobase + com_cfcr, sp->cfcr);
	/*
	 * XXX damp oscillations of MCR_DTR and MCR_RTS by not restoring them.
	 */
	outb(iobase + com_mcr, sp->mcr | MCR_DTR | MCR_RTS);
	outb(iobase + com_ier, sp->ier);
}

void
siocnprobe(cp)
	struct consdev	*cp;
{
	int	unit;

	/* locate the major number */
	/* XXX - should be elsewhere since KGDB uses it */
	for (commajor = 0; commajor < nchrdev; commajor++)
		if (cdevsw[commajor].d_open == sioopen)
			break;

	/* XXX: ick */
	unit = DEV_TO_UNIT(CONUNIT);
	siocniobase = CONADDR;

	/* make sure hardware exists?  XXX */

	/* initialize required fields */
	cp->cn_dev = makedev(commajor, unit);
#ifdef COMCONSOLE
	cp->cn_pri = CN_REMOTE;		/* Force a serial port console */
#else
	cp->cn_pri = (boothowto & RB_SERIAL) ? CN_REMOTE : CN_NORMAL;
#endif
}

void
siocninit(cp)
	struct consdev	*cp;
{
	comconsole = DEV_TO_UNIT(cp->cn_dev);
}

int
siocncheckc(dev)
	dev_t	dev;
{
	int	c;
	Port_t	iobase;
	int	s;
	struct siocnstate	sp;

	iobase = siocniobase;
	s = spltty();
	siocnopen(&sp);
	if (inb(iobase + com_lsr) & LSR_RXRDY)
		c = inb(iobase + com_data);
	else
		c = 0;
	siocnclose(&sp);
	splx(s);
	return (c);
}


int
siocngetc(dev)
	dev_t	dev;
{
	int	c;
	Port_t	iobase;
	int	s;
	struct siocnstate	sp;

	iobase = siocniobase;
	s = spltty();
	siocnopen(&sp);
	while (!(inb(iobase + com_lsr) & LSR_RXRDY))
		;
	c = inb(iobase + com_data);
	siocnclose(&sp);
	splx(s);
	return (c);
}

void
siocnputc(dev, c)
	dev_t	dev;
	int	c;
{
	int	s;
	struct siocnstate	sp;

	s = spltty();
	siocnopen(&sp);
	siocntxwait();
	outb(siocniobase + com_data, c);
	siocnclose(&sp);
	splx(s);
}

#ifdef DSI_SOFT_MODEM
/*
 * The magic code to download microcode to a "Connection 14.4+Fax"
 * modem from Digicom Systems Inc.  Very magic.
 */

#define DSI_ERROR(str) { ptr = str; goto error; }
static int
LoadSoftModem(int unit, int base_io, u_long size, u_char *ptr)
{
    int int_c,int_k;
    int data_0188, data_0187;

    /*
     * First see if it is a DSI SoftModem
     */
    if(!((inb(base_io+7) ^ inb(base_io+7) & 0x80)))
	return ENODEV;

    data_0188 = inb(base_io+4);
    data_0187 = inb(base_io+3);
    outb(base_io+3,0x80);
    outb(base_io+4,0x0C);
    outb(base_io+0,0x31);
    outb(base_io+1,0x8C);
    outb(base_io+7,0x10);
    outb(base_io+7,0x19);

    if(0x18 != (inb(base_io+7) & 0x1A))
	DSI_ERROR("dsp bus not granted");

    if(0x01 != (inb(base_io+7) & 0x01)) {
	outb(base_io+7,0x18);
	outb(base_io+7,0x19);
	if(0x01 != (inb(base_io+7) & 0x01))
	    DSI_ERROR("program mem not granted");
    }

    int_c = 0;

    while(1) {
	if(int_c >= 7 || size <= 0x1800)
	    break;

	for(int_k = 0 ; int_k < 0x800; int_k++) {
	    outb(base_io+0,*ptr++);
	    outb(base_io+1,*ptr++);
	    outb(base_io+2,*ptr++);
	}

	size -= 0x1800;
	int_c++;
    }

    if(size > 0x1800) {
 	outb(base_io+7,0x18);
 	outb(base_io+7,0x19);
	if(0x00 != (inb(base_io+7) & 0x01))
	    DSI_ERROR("program data not granted");

	for(int_k = 0 ; int_k < 0x800; int_k++) {
	    outb(base_io+1,*ptr++);
	    outb(base_io+2,0);
	    outb(base_io+1,*ptr++);
	    outb(base_io+2,*ptr++);
	}

	size -= 0x1800;

	while(size > 0x1800) {
	    for(int_k = 0 ; int_k < 0xC00; int_k++) {
		outb(base_io+1,*ptr++);
		outb(base_io+2,*ptr++);
	    }
	    size -= 0x1800;
	}

	if(size < 0x1800) {
	    for(int_k=0;int_k<size/2;int_k++) {
		outb(base_io+1,*ptr++);
		outb(base_io+2,*ptr++);
	    }
	}

    } else if (size > 0) {
	if(int_c == 7) {
	    outb(base_io+7,0x18);
	    outb(base_io+7,0x19);
	    if(0x00 != (inb(base_io+7) & 0x01))
		DSI_ERROR("program data not granted");
	    for(int_k = 0 ; int_k < size/3; int_k++) {
		outb(base_io+1,*ptr++);
		outb(base_io+2,0);
		outb(base_io+1,*ptr++);
		outb(base_io+2,*ptr++);
	    }
	} else {
	    for(int_k = 0 ; int_k < size/3; int_k++) {
		outb(base_io+0,*ptr++);
		outb(base_io+1,*ptr++);
		outb(base_io+2,*ptr++);
	    }
	}
    }
    outb(base_io+7,0x11);
    outb(base_io+7,3);

    outb(base_io+4,data_0188 & 0xfb);

    outb(base_io+3,data_0187);

    return 0;
error:
    printf("sio%d: DSI SoftModem microcode load failed: <%s>\n",unit,ptr);
    outb(base_io+7,0x00); \
    outb(base_io+3,data_0187); \
    outb(base_io+4,data_0188);  \
    return EIO;
}
#endif /* DSI_SOFT_MODEM */

#endif /* NSIO > 0 */
OpenPOWER on IntegriCloud