summaryrefslogtreecommitdiffstats
path: root/drivers/serial/ioc4_serial.c
blob: 5ec4716c99bf30e5bd16bb271e45aa1f38207343 (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
2560
2561
2562
2563
2564
2565
2566
2567
2568
2569
2570
2571
2572
2573
2574
2575
2576
2577
2578
2579
2580
2581
2582
2583
2584
2585
2586
2587
2588
2589
2590
2591
2592
2593
2594
2595
2596
2597
2598
2599
2600
2601
2602
2603
2604
2605
2606
2607
2608
2609
2610
2611
2612
2613
2614
2615
2616
2617
2618
2619
2620
2621
2622
2623
2624
2625
2626
2627
2628
2629
2630
2631
2632
2633
2634
2635
2636
2637
2638
2639
2640
2641
2642
2643
2644
2645
2646
2647
2648
2649
2650
2651
2652
2653
2654
2655
2656
2657
2658
2659
2660
2661
2662
2663
2664
2665
2666
2667
2668
2669
2670
2671
2672
2673
2674
2675
2676
2677
2678
2679
2680
2681
2682
2683
2684
2685
2686
2687
2688
2689
2690
2691
2692
2693
2694
2695
2696
2697
2698
2699
2700
2701
2702
2703
2704
2705
2706
2707
2708
2709
2710
2711
2712
2713
2714
2715
2716
2717
2718
2719
2720
2721
2722
2723
2724
2725
2726
2727
2728
2729
2730
2731
2732
2733
2734
2735
2736
2737
2738
2739
2740
2741
2742
2743
2744
2745
2746
2747
2748
2749
2750
2751
2752
2753
2754
2755
2756
2757
2758
2759
2760
2761
2762
2763
2764
2765
2766
2767
2768
2769
2770
2771
2772
2773
2774
2775
2776
2777
2778
2779
2780
2781
2782
2783
2784
2785
2786
2787
2788
2789
2790
2791
2792
2793
2794
2795
2796
2797
2798
2799
2800
2801
2802
2803
2804
2805
2806
2807
2808
2809
2810
2811
2812
2813
2814
2815
2816
2817
2818
2819
2820
2821
2822
2823
2824
2825
2826
2827
2828
2829
2830
2831
2832
2833
2834
2835
2836
2837
2838
2839
2840
2841
2842
2843
2844
2845
2846
2847
2848
2849
2850
2851
2852
2853
2854
2855
2856
2857
2858
2859
2860
2861
2862
2863
2864
2865
2866
2867
2868
2869
2870
2871
2872
2873
2874
2875
2876
2877
2878
2879
2880
2881
2882
2883
2884
2885
2886
2887
2888
2889
2890
2891
2892
2893
2894
2895
2896
2897
2898
2899
2900
2901
2902
2903
2904
2905
2906
2907
2908
2909
2910
2911
2912
2913
2914
2915
2916
2917
2918
2919
2920
2921
2922
2923
2924
2925
2926
2927
2928
2929
2930
2931
2932
2933
2934
2935
2936
2937
2938
2939
2940
2941
2942
2943
2944
/*
 * This file is subject to the terms and conditions of the GNU General Public
 * License.  See the file "COPYING" in the main directory of this archive
 * for more details.
 *
 * Copyright (C) 2003-2006 Silicon Graphics, Inc.  All Rights Reserved.
 */


/*
 * This file contains a module version of the ioc4 serial driver. This
 * includes all the support functions needed (support functions, etc.)
 * and the serial driver itself.
 */
#include <linux/errno.h>
#include <linux/tty.h>
#include <linux/serial.h>
#include <linux/serialP.h>
#include <linux/circ_buf.h>
#include <linux/serial_reg.h>
#include <linux/module.h>
#include <linux/pci.h>
#include <linux/ioc4.h>
#include <linux/serial_core.h>

/*
 * interesting things about the ioc4
 */

#define IOC4_NUM_SERIAL_PORTS	4	/* max ports per card */
#define IOC4_NUM_CARDS		8	/* max cards per partition */

#define	GET_SIO_IR(_n)	(_n == 0) ? (IOC4_SIO_IR_S0) : \
				(_n == 1) ? (IOC4_SIO_IR_S1) : \
				(_n == 2) ? (IOC4_SIO_IR_S2) : \
				(IOC4_SIO_IR_S3)

#define	GET_OTHER_IR(_n)  (_n == 0) ? (IOC4_OTHER_IR_S0_MEMERR) : \
				(_n == 1) ? (IOC4_OTHER_IR_S1_MEMERR) : \
				(_n == 2) ? (IOC4_OTHER_IR_S2_MEMERR) : \
				(IOC4_OTHER_IR_S3_MEMERR)


/*
 * All IOC4 registers are 32 bits wide.
 */

/*
 * PCI Memory Space Map
 */
#define IOC4_PCI_ERR_ADDR_L     0x000	/* Low Error Address */
#define IOC4_PCI_ERR_ADDR_VLD	        (0x1 << 0)
#define IOC4_PCI_ERR_ADDR_MST_ID_MSK    (0xf << 1)
#define IOC4_PCI_ERR_ADDR_MST_NUM_MSK   (0xe << 1)
#define IOC4_PCI_ERR_ADDR_MST_TYP_MSK   (0x1 << 1)
#define IOC4_PCI_ERR_ADDR_MUL_ERR       (0x1 << 5)
#define IOC4_PCI_ERR_ADDR_ADDR_MSK      (0x3ffffff << 6)

/* Interrupt types */
#define	IOC4_SIO_INTR_TYPE	0
#define	IOC4_OTHER_INTR_TYPE	1
#define	IOC4_NUM_INTR_TYPES	2

/* Bitmasks for IOC4_SIO_IR, IOC4_SIO_IEC, and IOC4_SIO_IES  */
#define IOC4_SIO_IR_S0_TX_MT	   0x00000001	/* Serial port 0 TX empty */
#define IOC4_SIO_IR_S0_RX_FULL	   0x00000002	/* Port 0 RX buf full */
#define IOC4_SIO_IR_S0_RX_HIGH	   0x00000004	/* Port 0 RX hiwat */
#define IOC4_SIO_IR_S0_RX_TIMER	   0x00000008	/* Port 0 RX timeout */
#define IOC4_SIO_IR_S0_DELTA_DCD   0x00000010	/* Port 0 delta DCD */
#define IOC4_SIO_IR_S0_DELTA_CTS   0x00000020	/* Port 0 delta CTS */
#define IOC4_SIO_IR_S0_INT	   0x00000040	/* Port 0 pass-thru intr */
#define IOC4_SIO_IR_S0_TX_EXPLICIT 0x00000080	/* Port 0 explicit TX thru */
#define IOC4_SIO_IR_S1_TX_MT	   0x00000100	/* Serial port 1 */
#define IOC4_SIO_IR_S1_RX_FULL	   0x00000200	/* */
#define IOC4_SIO_IR_S1_RX_HIGH	   0x00000400	/* */
#define IOC4_SIO_IR_S1_RX_TIMER	   0x00000800	/* */
#define IOC4_SIO_IR_S1_DELTA_DCD   0x00001000	/* */
#define IOC4_SIO_IR_S1_DELTA_CTS   0x00002000	/* */
#define IOC4_SIO_IR_S1_INT	   0x00004000	/* */
#define IOC4_SIO_IR_S1_TX_EXPLICIT 0x00008000	/* */
#define IOC4_SIO_IR_S2_TX_MT	   0x00010000	/* Serial port 2 */
#define IOC4_SIO_IR_S2_RX_FULL	   0x00020000	/* */
#define IOC4_SIO_IR_S2_RX_HIGH	   0x00040000	/* */
#define IOC4_SIO_IR_S2_RX_TIMER	   0x00080000	/* */
#define IOC4_SIO_IR_S2_DELTA_DCD   0x00100000	/* */
#define IOC4_SIO_IR_S2_DELTA_CTS   0x00200000	/* */
#define IOC4_SIO_IR_S2_INT	   0x00400000	/* */
#define IOC4_SIO_IR_S2_TX_EXPLICIT 0x00800000	/* */
#define IOC4_SIO_IR_S3_TX_MT	   0x01000000	/* Serial port 3 */
#define IOC4_SIO_IR_S3_RX_FULL	   0x02000000	/* */
#define IOC4_SIO_IR_S3_RX_HIGH	   0x04000000	/* */
#define IOC4_SIO_IR_S3_RX_TIMER	   0x08000000	/* */
#define IOC4_SIO_IR_S3_DELTA_DCD   0x10000000	/* */
#define IOC4_SIO_IR_S3_DELTA_CTS   0x20000000	/* */
#define IOC4_SIO_IR_S3_INT	   0x40000000	/* */
#define IOC4_SIO_IR_S3_TX_EXPLICIT 0x80000000	/* */

/* Per device interrupt masks */
#define IOC4_SIO_IR_S0		(IOC4_SIO_IR_S0_TX_MT | \
				 IOC4_SIO_IR_S0_RX_FULL | \
				 IOC4_SIO_IR_S0_RX_HIGH | \
				 IOC4_SIO_IR_S0_RX_TIMER | \
				 IOC4_SIO_IR_S0_DELTA_DCD | \
				 IOC4_SIO_IR_S0_DELTA_CTS | \
				 IOC4_SIO_IR_S0_INT | \
				 IOC4_SIO_IR_S0_TX_EXPLICIT)
#define IOC4_SIO_IR_S1		(IOC4_SIO_IR_S1_TX_MT | \
				 IOC4_SIO_IR_S1_RX_FULL | \
				 IOC4_SIO_IR_S1_RX_HIGH | \
				 IOC4_SIO_IR_S1_RX_TIMER | \
				 IOC4_SIO_IR_S1_DELTA_DCD | \
				 IOC4_SIO_IR_S1_DELTA_CTS | \
				 IOC4_SIO_IR_S1_INT | \
				 IOC4_SIO_IR_S1_TX_EXPLICIT)
#define IOC4_SIO_IR_S2		(IOC4_SIO_IR_S2_TX_MT | \
				 IOC4_SIO_IR_S2_RX_FULL | \
				 IOC4_SIO_IR_S2_RX_HIGH | \
				 IOC4_SIO_IR_S2_RX_TIMER | \
				 IOC4_SIO_IR_S2_DELTA_DCD | \
				 IOC4_SIO_IR_S2_DELTA_CTS | \
				 IOC4_SIO_IR_S2_INT | \
				 IOC4_SIO_IR_S2_TX_EXPLICIT)
#define IOC4_SIO_IR_S3		(IOC4_SIO_IR_S3_TX_MT | \
				 IOC4_SIO_IR_S3_RX_FULL | \
				 IOC4_SIO_IR_S3_RX_HIGH | \
				 IOC4_SIO_IR_S3_RX_TIMER | \
				 IOC4_SIO_IR_S3_DELTA_DCD | \
				 IOC4_SIO_IR_S3_DELTA_CTS | \
				 IOC4_SIO_IR_S3_INT | \
				 IOC4_SIO_IR_S3_TX_EXPLICIT)

/* Bitmasks for IOC4_OTHER_IR, IOC4_OTHER_IEC, and IOC4_OTHER_IES  */
#define IOC4_OTHER_IR_ATA_INT		0x00000001  /* ATAPI intr pass-thru */
#define IOC4_OTHER_IR_ATA_MEMERR	0x00000002  /* ATAPI DMA PCI error */
#define IOC4_OTHER_IR_S0_MEMERR		0x00000004  /* Port 0 PCI error */
#define IOC4_OTHER_IR_S1_MEMERR		0x00000008  /* Port 1 PCI error */
#define IOC4_OTHER_IR_S2_MEMERR		0x00000010  /* Port 2 PCI error */
#define IOC4_OTHER_IR_S3_MEMERR		0x00000020  /* Port 3 PCI error */
#define IOC4_OTHER_IR_KBD_INT		0x00000040  /* Keyboard/mouse */
#define IOC4_OTHER_IR_RESERVED		0x007fff80  /* Reserved */
#define IOC4_OTHER_IR_RT_INT		0x00800000  /* INT_OUT section output */
#define IOC4_OTHER_IR_GEN_INT		0xff000000  /* Generic pins */

#define IOC4_OTHER_IR_SER_MEMERR (IOC4_OTHER_IR_S0_MEMERR | IOC4_OTHER_IR_S1_MEMERR | \
				  IOC4_OTHER_IR_S2_MEMERR | IOC4_OTHER_IR_S3_MEMERR)

/* Bitmasks for IOC4_SIO_CR */
#define IOC4_SIO_CR_CMD_PULSE_SHIFT              0  /* byte bus strobe shift */
#define IOC4_SIO_CR_ARB_DIAG_TX0	0x00000000
#define IOC4_SIO_CR_ARB_DIAG_RX0	0x00000010
#define IOC4_SIO_CR_ARB_DIAG_TX1	0x00000020
#define IOC4_SIO_CR_ARB_DIAG_RX1	0x00000030
#define IOC4_SIO_CR_ARB_DIAG_TX2	0x00000040
#define IOC4_SIO_CR_ARB_DIAG_RX2	0x00000050
#define IOC4_SIO_CR_ARB_DIAG_TX3	0x00000060
#define IOC4_SIO_CR_ARB_DIAG_RX3	0x00000070
#define IOC4_SIO_CR_SIO_DIAG_IDLE	0x00000080  /* 0 -> active request among
							   serial ports (ro) */
/* Defs for some of the generic I/O pins */
#define IOC4_GPCR_UART0_MODESEL	   0x10	/* Pin is output to port 0
						   mode sel */
#define IOC4_GPCR_UART1_MODESEL	   0x20	/* Pin is output to port 1
						   mode sel */
#define IOC4_GPCR_UART2_MODESEL	   0x40	/* Pin is output to port 2
						   mode sel */
#define IOC4_GPCR_UART3_MODESEL	   0x80	/* Pin is output to port 3
						   mode sel */

#define IOC4_GPPR_UART0_MODESEL_PIN   4	/* GIO pin controlling
					   uart 0 mode select */
#define IOC4_GPPR_UART1_MODESEL_PIN   5	/* GIO pin controlling
					   uart 1 mode select */
#define IOC4_GPPR_UART2_MODESEL_PIN   6	/* GIO pin controlling
					   uart 2 mode select */
#define IOC4_GPPR_UART3_MODESEL_PIN   7	/* GIO pin controlling
					   uart 3 mode select */

/* Bitmasks for serial RX status byte */
#define IOC4_RXSB_OVERRUN       0x01	/* Char(s) lost */
#define IOC4_RXSB_PAR_ERR	0x02	/* Parity error */
#define IOC4_RXSB_FRAME_ERR	0x04	/* Framing error */
#define IOC4_RXSB_BREAK	        0x08	/* Break character */
#define IOC4_RXSB_CTS	        0x10	/* State of CTS */
#define IOC4_RXSB_DCD	        0x20	/* State of DCD */
#define IOC4_RXSB_MODEM_VALID   0x40	/* DCD, CTS, and OVERRUN are valid */
#define IOC4_RXSB_DATA_VALID    0x80	/* Data byte, FRAME_ERR PAR_ERR
					 * & BREAK valid */

/* Bitmasks for serial TX control byte */
#define IOC4_TXCB_INT_WHEN_DONE 0x20	/* Interrupt after this byte is sent */
#define IOC4_TXCB_INVALID	0x00	/* Byte is invalid */
#define IOC4_TXCB_VALID	        0x40	/* Byte is valid */
#define IOC4_TXCB_MCR	        0x80	/* Data<7:0> to modem control reg */
#define IOC4_TXCB_DELAY	        0xc0	/* Delay data<7:0> mSec */

/* Bitmasks for IOC4_SBBR_L */
#define IOC4_SBBR_L_SIZE	0x00000001  /* 0 == 1KB rings, 1 == 4KB rings */

/* Bitmasks for IOC4_SSCR_<3:0> */
#define IOC4_SSCR_RX_THRESHOLD  0x000001ff  /* Hiwater mark */
#define IOC4_SSCR_TX_TIMER_BUSY 0x00010000  /* TX timer in progress */
#define IOC4_SSCR_HFC_EN	0x00020000  /* Hardware flow control enabled */
#define IOC4_SSCR_RX_RING_DCD   0x00040000  /* Post RX record on delta-DCD */
#define IOC4_SSCR_RX_RING_CTS   0x00080000  /* Post RX record on delta-CTS */
#define IOC4_SSCR_DIAG	        0x00200000  /* Bypass clock divider for sim */
#define IOC4_SSCR_RX_DRAIN	0x08000000  /* Drain RX buffer to memory */
#define IOC4_SSCR_DMA_EN	0x10000000  /* Enable ring buffer DMA */
#define IOC4_SSCR_DMA_PAUSE	0x20000000  /* Pause DMA */
#define IOC4_SSCR_PAUSE_STATE   0x40000000  /* Sets when PAUSE takes effect */
#define IOC4_SSCR_RESET	        0x80000000  /* Reset DMA channels */

/* All producer/comsumer pointers are the same bitfield */
#define IOC4_PROD_CONS_PTR_4K   0x00000ff8	/* For 4K buffers */
#define IOC4_PROD_CONS_PTR_1K   0x000003f8	/* For 1K buffers */
#define IOC4_PROD_CONS_PTR_OFF           3

/* Bitmasks for IOC4_SRCIR_<3:0> */
#define IOC4_SRCIR_ARM	        0x80000000	/* Arm RX timer */

/* Bitmasks for IOC4_SHADOW_<3:0> */
#define IOC4_SHADOW_DR	 0x00000001	/* Data ready */
#define IOC4_SHADOW_OE	 0x00000002	/* Overrun error */
#define IOC4_SHADOW_PE	 0x00000004	/* Parity error */
#define IOC4_SHADOW_FE	 0x00000008	/* Framing error */
#define IOC4_SHADOW_BI	 0x00000010	/* Break interrupt */
#define IOC4_SHADOW_THRE 0x00000020	/* Xmit holding register empty */
#define IOC4_SHADOW_TEMT 0x00000040	/* Xmit shift register empty */
#define IOC4_SHADOW_RFCE 0x00000080	/* Char in RX fifo has an error */
#define IOC4_SHADOW_DCTS 0x00010000	/* Delta clear to send */
#define IOC4_SHADOW_DDCD 0x00080000	/* Delta data carrier detect */
#define IOC4_SHADOW_CTS	 0x00100000	/* Clear to send */
#define IOC4_SHADOW_DCD	 0x00800000	/* Data carrier detect */
#define IOC4_SHADOW_DTR	 0x01000000	/* Data terminal ready */
#define IOC4_SHADOW_RTS	 0x02000000	/* Request to send */
#define IOC4_SHADOW_OUT1 0x04000000	/* 16550 OUT1 bit */
#define IOC4_SHADOW_OUT2 0x08000000	/* 16550 OUT2 bit */
#define IOC4_SHADOW_LOOP 0x10000000	/* Loopback enabled */

/* Bitmasks for IOC4_SRTR_<3:0> */
#define IOC4_SRTR_CNT	        0x00000fff	/* Reload value for RX timer */
#define IOC4_SRTR_CNT_VAL	0x0fff0000	/* Current value of RX timer */
#define IOC4_SRTR_CNT_VAL_SHIFT         16
#define IOC4_SRTR_HZ                 16000	/* SRTR clock frequency */

/* Serial port register map used for DMA and PIO serial I/O */
struct ioc4_serialregs {
	uint32_t sscr;
	uint32_t stpir;
	uint32_t stcir;
	uint32_t srpir;
	uint32_t srcir;
	uint32_t srtr;
	uint32_t shadow;
};

/* IOC4 UART register map */
struct ioc4_uartregs {
	char i4u_lcr;
	union {
		char iir;	/* read only */
		char fcr;	/* write only */
	} u3;
	union {
		char ier;	/* DLAB == 0 */
		char dlm;	/* DLAB == 1 */
	} u2;
	union {
		char rbr;	/* read only, DLAB == 0 */
		char thr;	/* write only, DLAB == 0 */
		char dll;	/* DLAB == 1 */
	} u1;
	char i4u_scr;
	char i4u_msr;
	char i4u_lsr;
	char i4u_mcr;
};

/* short names */
#define i4u_dll u1.dll
#define i4u_ier u2.ier
#define i4u_dlm u2.dlm
#define i4u_fcr u3.fcr

/* Serial port registers used for DMA serial I/O */
struct ioc4_serial {
	uint32_t sbbr01_l;
	uint32_t sbbr01_h;
	uint32_t sbbr23_l;
	uint32_t sbbr23_h;

	struct ioc4_serialregs port_0;
	struct ioc4_serialregs port_1;
	struct ioc4_serialregs port_2;
	struct ioc4_serialregs port_3;
	struct ioc4_uartregs uart_0;
	struct ioc4_uartregs uart_1;
	struct ioc4_uartregs uart_2;
	struct ioc4_uartregs uart_3;
} ioc4_serial;

/* UART clock speed */
#define IOC4_SER_XIN_CLK_66     66666667
#define IOC4_SER_XIN_CLK_33     33333333

#define IOC4_W_IES		0
#define IOC4_W_IEC		1

typedef void ioc4_intr_func_f(void *, uint32_t);
typedef ioc4_intr_func_f *ioc4_intr_func_t;

static unsigned int Num_of_ioc4_cards;

/* defining this will get you LOTS of great debug info */
//#define DEBUG_INTERRUPTS
#define DPRINT_CONFIG(_x...)	;
//#define DPRINT_CONFIG(_x...)	printk _x

/* number of characters left in xmit buffer before we ask for more */
#define WAKEUP_CHARS	256

/* number of characters we want to transmit to the lower level at a time */
#define IOC4_MAX_CHARS	256
#define IOC4_FIFO_CHARS	255

/* Device name we're using */
#define DEVICE_NAME_RS232  "ttyIOC"
#define DEVICE_NAME_RS422  "ttyAIOC"
#define DEVICE_MAJOR	   204
#define DEVICE_MINOR_RS232 50
#define DEVICE_MINOR_RS422 84


/* register offsets */
#define IOC4_SERIAL_OFFSET	0x300

/* flags for next_char_state */
#define NCS_BREAK	0x1
#define NCS_PARITY	0x2
#define NCS_FRAMING	0x4
#define NCS_OVERRUN	0x8

/* cause we need SOME parameters ... */
#define MIN_BAUD_SUPPORTED	1200
#define MAX_BAUD_SUPPORTED	115200

/* protocol types supported */
#define PROTO_RS232	3
#define PROTO_RS422	7

/* Notification types */
#define N_DATA_READY	0x01
#define N_OUTPUT_LOWAT	0x02
#define N_BREAK		0x04
#define N_PARITY_ERROR	0x08
#define N_FRAMING_ERROR	0x10
#define N_OVERRUN_ERROR	0x20
#define N_DDCD		0x40
#define N_DCTS		0x80

#define N_ALL_INPUT	(N_DATA_READY | N_BREAK |			\
			 N_PARITY_ERROR | N_FRAMING_ERROR |		\
			 N_OVERRUN_ERROR | N_DDCD | N_DCTS)

#define N_ALL_OUTPUT	N_OUTPUT_LOWAT

#define N_ALL_ERRORS	(N_PARITY_ERROR | N_FRAMING_ERROR | N_OVERRUN_ERROR)

#define N_ALL		(N_DATA_READY | N_OUTPUT_LOWAT | N_BREAK |	\
			 N_PARITY_ERROR | N_FRAMING_ERROR |		\
			 N_OVERRUN_ERROR | N_DDCD | N_DCTS)

#define SER_DIVISOR(_x, clk)		(((clk) + (_x) * 8) / ((_x) * 16))
#define DIVISOR_TO_BAUD(div, clk)	((clk) / 16 / (div))

/* Some masks */
#define LCR_MASK_BITS_CHAR	(UART_LCR_WLEN5 | UART_LCR_WLEN6 \
					| UART_LCR_WLEN7 | UART_LCR_WLEN8)
#define LCR_MASK_STOP_BITS	(UART_LCR_STOP)

#define PENDING(_p)	(readl(&(_p)->ip_mem->sio_ir.raw) & _p->ip_ienb)
#define READ_SIO_IR(_p) readl(&(_p)->ip_mem->sio_ir.raw)

/* Default to 4k buffers */
#ifdef IOC4_1K_BUFFERS
#define RING_BUF_SIZE 1024
#define IOC4_BUF_SIZE_BIT 0
#define PROD_CONS_MASK IOC4_PROD_CONS_PTR_1K
#else
#define RING_BUF_SIZE 4096
#define IOC4_BUF_SIZE_BIT IOC4_SBBR_L_SIZE
#define PROD_CONS_MASK IOC4_PROD_CONS_PTR_4K
#endif

#define TOTAL_RING_BUF_SIZE (RING_BUF_SIZE * 4)

/*
 * This is the entry saved by the driver - one per card
 */

#define UART_PORT_MIN		0
#define UART_PORT_RS232		UART_PORT_MIN
#define UART_PORT_RS422		1
#define UART_PORT_COUNT		2	/* one for each mode */

struct ioc4_control {
	int ic_irq;
	struct {
		/* uart ports are allocated here - 1 for rs232, 1 for rs422 */
		struct uart_port icp_uart_port[UART_PORT_COUNT];
		/* Handy reference material */
		struct ioc4_port *icp_port;
	} ic_port[IOC4_NUM_SERIAL_PORTS];
	struct ioc4_soft *ic_soft;
};

/*
 * per-IOC4 data structure
 */
#define MAX_IOC4_INTR_ENTS	(8 * sizeof(uint32_t))
struct ioc4_soft {
	struct ioc4_misc_regs __iomem *is_ioc4_misc_addr;
	struct ioc4_serial __iomem *is_ioc4_serial_addr;

	/* Each interrupt type has an entry in the array */
	struct ioc4_intr_type {

		/*
		 * Each in-use entry in this array contains at least
		 * one nonzero bit in sd_bits; no two entries in this
		 * array have overlapping sd_bits values.
		 */
		struct ioc4_intr_info {
			uint32_t sd_bits;
			ioc4_intr_func_f *sd_intr;
			void *sd_info;
		} is_intr_info[MAX_IOC4_INTR_ENTS];

		/* Number of entries active in the above array */
		atomic_t is_num_intrs;
	} is_intr_type[IOC4_NUM_INTR_TYPES];

	/* is_ir_lock must be held while
	 * modifying sio_ie values, so
	 * we can be sure that sio_ie is
	 * not changing when we read it
	 * along with sio_ir.
	 */
	spinlock_t is_ir_lock;	/* SIO_IE[SC] mod lock */
};

/* Local port info for each IOC4 serial ports */
struct ioc4_port {
	struct uart_port *ip_port;	/* current active port ptr */
	/* Ptrs for all ports */
	struct uart_port *ip_all_ports[UART_PORT_COUNT];
	/* Back ptrs for this port */
	struct ioc4_control *ip_control;
	struct pci_dev *ip_pdev;
	struct ioc4_soft *ip_ioc4_soft;

	/* pci mem addresses */
	struct ioc4_misc_regs __iomem *ip_mem;
	struct ioc4_serial __iomem *ip_serial;
	struct ioc4_serialregs __iomem *ip_serial_regs;
	struct ioc4_uartregs __iomem *ip_uart_regs;

	/* Ring buffer page for this port */
	dma_addr_t ip_dma_ringbuf;
	/* vaddr of ring buffer */
	struct ring_buffer *ip_cpu_ringbuf;

	/* Rings for this port */
	struct ring *ip_inring;
	struct ring *ip_outring;

	/* Hook to port specific values */
	struct hooks *ip_hooks;

	spinlock_t ip_lock;

	/* Various rx/tx parameters */
	int ip_baud;
	int ip_tx_lowat;
	int ip_rx_timeout;

	/* Copy of notification bits */
	int ip_notify;

	/* Shadow copies of various registers so we don't need to PIO
	 * read them constantly
	 */
	uint32_t ip_ienb;	/* Enabled interrupts */
	uint32_t ip_sscr;
	uint32_t ip_tx_prod;
	uint32_t ip_rx_cons;
	int ip_pci_bus_speed;
	unsigned char ip_flags;
};

/* tx low water mark.  We need to notify the driver whenever tx is getting
 * close to empty so it can refill the tx buffer and keep things going.
 * Let's assume that if we interrupt 1 ms before the tx goes idle, we'll
 * have no trouble getting in more chars in time (I certainly hope so).
 */
#define TX_LOWAT_LATENCY      1000
#define TX_LOWAT_HZ          (1000000 / TX_LOWAT_LATENCY)
#define TX_LOWAT_CHARS(baud) (baud / 10 / TX_LOWAT_HZ)

/* Flags per port */
#define INPUT_HIGH	0x01
#define DCD_ON		0x02
#define LOWAT_WRITTEN	0x04
#define READ_ABORTED	0x08
#define PORT_ACTIVE	0x10
#define PORT_INACTIVE	0	/* This is the value when "off" */


/* Since each port has different register offsets and bitmasks
 * for everything, we'll store those that we need in tables so we
 * don't have to be constantly checking the port we are dealing with.
 */
struct hooks {
	uint32_t intr_delta_dcd;
	uint32_t intr_delta_cts;
	uint32_t intr_tx_mt;
	uint32_t intr_rx_timer;
	uint32_t intr_rx_high;
	uint32_t intr_tx_explicit;
	uint32_t intr_dma_error;
	uint32_t intr_clear;
	uint32_t intr_all;
	int rs422_select_pin;
};

static struct hooks hooks_array[IOC4_NUM_SERIAL_PORTS] = {
	/* Values for port 0 */
	{
	 IOC4_SIO_IR_S0_DELTA_DCD, IOC4_SIO_IR_S0_DELTA_CTS,
	 IOC4_SIO_IR_S0_TX_MT, IOC4_SIO_IR_S0_RX_TIMER,
	 IOC4_SIO_IR_S0_RX_HIGH, IOC4_SIO_IR_S0_TX_EXPLICIT,
	 IOC4_OTHER_IR_S0_MEMERR,
	 (IOC4_SIO_IR_S0_TX_MT | IOC4_SIO_IR_S0_RX_FULL |
	  IOC4_SIO_IR_S0_RX_HIGH | IOC4_SIO_IR_S0_RX_TIMER |
	  IOC4_SIO_IR_S0_DELTA_DCD | IOC4_SIO_IR_S0_DELTA_CTS |
	  IOC4_SIO_IR_S0_INT | IOC4_SIO_IR_S0_TX_EXPLICIT),
	 IOC4_SIO_IR_S0, IOC4_GPPR_UART0_MODESEL_PIN,
	 },

	/* Values for port 1 */
	{
	 IOC4_SIO_IR_S1_DELTA_DCD, IOC4_SIO_IR_S1_DELTA_CTS,
	 IOC4_SIO_IR_S1_TX_MT, IOC4_SIO_IR_S1_RX_TIMER,
	 IOC4_SIO_IR_S1_RX_HIGH, IOC4_SIO_IR_S1_TX_EXPLICIT,
	 IOC4_OTHER_IR_S1_MEMERR,
	 (IOC4_SIO_IR_S1_TX_MT | IOC4_SIO_IR_S1_RX_FULL |
	  IOC4_SIO_IR_S1_RX_HIGH | IOC4_SIO_IR_S1_RX_TIMER |
	  IOC4_SIO_IR_S1_DELTA_DCD | IOC4_SIO_IR_S1_DELTA_CTS |
	  IOC4_SIO_IR_S1_INT | IOC4_SIO_IR_S1_TX_EXPLICIT),
	 IOC4_SIO_IR_S1, IOC4_GPPR_UART1_MODESEL_PIN,
	 },

	/* Values for port 2 */
	{
	 IOC4_SIO_IR_S2_DELTA_DCD, IOC4_SIO_IR_S2_DELTA_CTS,
	 IOC4_SIO_IR_S2_TX_MT, IOC4_SIO_IR_S2_RX_TIMER,
	 IOC4_SIO_IR_S2_RX_HIGH, IOC4_SIO_IR_S2_TX_EXPLICIT,
	 IOC4_OTHER_IR_S2_MEMERR,
	 (IOC4_SIO_IR_S2_TX_MT | IOC4_SIO_IR_S2_RX_FULL |
	  IOC4_SIO_IR_S2_RX_HIGH | IOC4_SIO_IR_S2_RX_TIMER |
	  IOC4_SIO_IR_S2_DELTA_DCD | IOC4_SIO_IR_S2_DELTA_CTS |
	  IOC4_SIO_IR_S2_INT | IOC4_SIO_IR_S2_TX_EXPLICIT),
	 IOC4_SIO_IR_S2, IOC4_GPPR_UART2_MODESEL_PIN,
	 },

	/* Values for port 3 */
	{
	 IOC4_SIO_IR_S3_DELTA_DCD, IOC4_SIO_IR_S3_DELTA_CTS,
	 IOC4_SIO_IR_S3_TX_MT, IOC4_SIO_IR_S3_RX_TIMER,
	 IOC4_SIO_IR_S3_RX_HIGH, IOC4_SIO_IR_S3_TX_EXPLICIT,
	 IOC4_OTHER_IR_S3_MEMERR,
	 (IOC4_SIO_IR_S3_TX_MT | IOC4_SIO_IR_S3_RX_FULL |
	  IOC4_SIO_IR_S3_RX_HIGH | IOC4_SIO_IR_S3_RX_TIMER |
	  IOC4_SIO_IR_S3_DELTA_DCD | IOC4_SIO_IR_S3_DELTA_CTS |
	  IOC4_SIO_IR_S3_INT | IOC4_SIO_IR_S3_TX_EXPLICIT),
	 IOC4_SIO_IR_S3, IOC4_GPPR_UART3_MODESEL_PIN,
	 }
};

/* A ring buffer entry */
struct ring_entry {
	union {
		struct {
			uint32_t alldata;
			uint32_t allsc;
		} all;
		struct {
			char data[4];	/* data bytes */
			char sc[4];	/* status/control */
		} s;
	} u;
};

/* Test the valid bits in any of the 4 sc chars using "allsc" member */
#define RING_ANY_VALID \
	((uint32_t)(IOC4_RXSB_MODEM_VALID | IOC4_RXSB_DATA_VALID) * 0x01010101)

#define ring_sc     u.s.sc
#define ring_data   u.s.data
#define ring_allsc  u.all.allsc

/* Number of entries per ring buffer. */
#define ENTRIES_PER_RING (RING_BUF_SIZE / (int) sizeof(struct ring_entry))

/* An individual ring */
struct ring {
	struct ring_entry entries[ENTRIES_PER_RING];
};

/* The whole enchilada */
struct ring_buffer {
	struct ring TX_0_OR_2;
	struct ring RX_0_OR_2;
	struct ring TX_1_OR_3;
	struct ring RX_1_OR_3;
};

/* Get a ring from a port struct */
#define RING(_p, _wh)	&(((struct ring_buffer *)((_p)->ip_cpu_ringbuf))->_wh)

/* Infinite loop detection.
 */
#define MAXITER 10000000

/* Prototypes */
static void receive_chars(struct uart_port *);
static void handle_intr(void *arg, uint32_t sio_ir);

/*
 * port_is_active - determines if this port is currently active
 * @port: ptr to soft struct for this port
 * @uart_port: uart port to test for
 */
static inline int port_is_active(struct ioc4_port *port,
		struct uart_port *uart_port)
{
	if (port) {
		if ((port->ip_flags & PORT_ACTIVE)
					&& (port->ip_port == uart_port))
			return 1;
	}
	return 0;
}


/**
 * write_ireg - write the interrupt regs
 * @ioc4_soft: ptr to soft struct for this port
 * @val: value to write
 * @which: which register
 * @type: which ireg set
 */
static inline void
write_ireg(struct ioc4_soft *ioc4_soft, uint32_t val, int which, int type)
{
	struct ioc4_misc_regs __iomem *mem = ioc4_soft->is_ioc4_misc_addr;
	unsigned long flags;

	spin_lock_irqsave(&ioc4_soft->is_ir_lock, flags);

	switch (type) {
	case IOC4_SIO_INTR_TYPE:
		switch (which) {
		case IOC4_W_IES:
			writel(val, &mem->sio_ies.raw);
			break;

		case IOC4_W_IEC:
			writel(val, &mem->sio_iec.raw);
			break;
		}
		break;

	case IOC4_OTHER_INTR_TYPE:
		switch (which) {
		case IOC4_W_IES:
			writel(val, &mem->other_ies.raw);
			break;

		case IOC4_W_IEC:
			writel(val, &mem->other_iec.raw);
			break;
		}
		break;

	default:
		break;
	}
	spin_unlock_irqrestore(&ioc4_soft->is_ir_lock, flags);
}

/**
 * set_baud - Baud rate setting code
 * @port: port to set
 * @baud: baud rate to use
 */
static int set_baud(struct ioc4_port *port, int baud)
{
	int actual_baud;
	int diff;
	int lcr;
	unsigned short divisor;
	struct ioc4_uartregs __iomem *uart;

	divisor = SER_DIVISOR(baud, port->ip_pci_bus_speed);
	if (!divisor)
		return 1;
	actual_baud = DIVISOR_TO_BAUD(divisor, port->ip_pci_bus_speed);

	diff = actual_baud - baud;
	if (diff < 0)
		diff = -diff;

	/* If we're within 1%, we've found a match */
	if (diff * 100 > actual_baud)
		return 1;

	uart = port->ip_uart_regs;
	lcr = readb(&uart->i4u_lcr);
	writeb(lcr | UART_LCR_DLAB, &uart->i4u_lcr);
	writeb((unsigned char)divisor, &uart->i4u_dll);
	writeb((unsigned char)(divisor >> 8), &uart->i4u_dlm);
	writeb(lcr, &uart->i4u_lcr);
	return 0;
}


/**
 * get_ioc4_port - given a uart port, return the control structure
 * @port: uart port
 * @set: set this port as current
 */
static struct ioc4_port *get_ioc4_port(struct uart_port *the_port, int set)
{
	struct ioc4_driver_data *idd = dev_get_drvdata(the_port->dev);
	struct ioc4_control *control = idd->idd_serial_data;
	struct ioc4_port *port;
	int port_num, port_type;

	if (control) {
		for ( port_num = 0; port_num < IOC4_NUM_SERIAL_PORTS;
							port_num++ ) {
			port = control->ic_port[port_num].icp_port;
			if (!port)
				continue;
			for (port_type = UART_PORT_MIN;
						port_type < UART_PORT_COUNT;
						port_type++) {
				if (the_port == port->ip_all_ports
							[port_type]) {
					/* set local copy */
					if (set) {
						port->ip_port = the_port;
					}
					return port;
				}
			}
		}
	}
	return NULL;
}

/* The IOC4 hardware provides no atomic way to determine if interrupts
 * are pending since two reads are required to do so.  The handler must
 * read the SIO_IR and the SIO_IES, and take the logical and of the
 * two.  When this value is zero, all interrupts have been serviced and
 * the handler may return.
 *
 * This has the unfortunate "hole" that, if some other CPU or
 * some other thread or some higher level interrupt manages to
 * modify SIO_IE between our reads of SIO_IR and SIO_IE, we may
 * think we have observed SIO_IR&SIO_IE==0 when in fact this
 * condition never really occurred.
 *
 * To solve this, we use a simple spinlock that must be held
 * whenever modifying SIO_IE; holding this lock while observing
 * both SIO_IR and SIO_IE guarantees that we do not falsely
 * conclude that no enabled interrupts are pending.
 */

static inline uint32_t
pending_intrs(struct ioc4_soft *soft, int type)
{
	struct ioc4_misc_regs __iomem *mem = soft->is_ioc4_misc_addr;
	unsigned long flag;
	uint32_t intrs = 0;

	BUG_ON(!((type == IOC4_SIO_INTR_TYPE)
	       || (type == IOC4_OTHER_INTR_TYPE)));

	spin_lock_irqsave(&soft->is_ir_lock, flag);

	switch (type) {
	case IOC4_SIO_INTR_TYPE:
		intrs = readl(&mem->sio_ir.raw) & readl(&mem->sio_ies.raw);
		break;

	case IOC4_OTHER_INTR_TYPE:
		intrs = readl(&mem->other_ir.raw) & readl(&mem->other_ies.raw);

		/* Don't process any ATA interrupte */
		intrs &= ~(IOC4_OTHER_IR_ATA_INT | IOC4_OTHER_IR_ATA_MEMERR);
		break;

	default:
		break;
	}
	spin_unlock_irqrestore(&soft->is_ir_lock, flag);
	return intrs;
}

/**
 * port_init - Initialize the sio and ioc4 hardware for a given port
 *			called per port from attach...
 * @port: port to initialize
 */
static int inline port_init(struct ioc4_port *port)
{
	uint32_t sio_cr;
	struct hooks *hooks = port->ip_hooks;
	struct ioc4_uartregs __iomem *uart;

	/* Idle the IOC4 serial interface */
	writel(IOC4_SSCR_RESET, &port->ip_serial_regs->sscr);

	/* Wait until any pending bus activity for this port has ceased */
	do
		sio_cr = readl(&port->ip_mem->sio_cr.raw);
	while (!(sio_cr & IOC4_SIO_CR_SIO_DIAG_IDLE));

	/* Finish reset sequence */
	writel(0, &port->ip_serial_regs->sscr);

	/* Once RESET is done, reload cached tx_prod and rx_cons values
	 * and set rings to empty by making prod == cons
	 */
	port->ip_tx_prod = readl(&port->ip_serial_regs->stcir) & PROD_CONS_MASK;
	writel(port->ip_tx_prod, &port->ip_serial_regs->stpir);
	port->ip_rx_cons = readl(&port->ip_serial_regs->srpir) & PROD_CONS_MASK;
	writel(port->ip_rx_cons | IOC4_SRCIR_ARM, &port->ip_serial_regs->srcir);

	/* Disable interrupts for this 16550 */
	uart = port->ip_uart_regs;
	writeb(0, &uart->i4u_lcr);
	writeb(0, &uart->i4u_ier);

	/* Set the default baud */
	set_baud(port, port->ip_baud);

	/* Set line control to 8 bits no parity */
	writeb(UART_LCR_WLEN8 | 0, &uart->i4u_lcr);
					/* UART_LCR_STOP == 1 stop */

	/* Enable the FIFOs */
	writeb(UART_FCR_ENABLE_FIFO, &uart->i4u_fcr);
	/* then reset 16550 FIFOs */
	writeb(UART_FCR_ENABLE_FIFO | UART_FCR_CLEAR_RCVR | UART_FCR_CLEAR_XMIT,
			&uart->i4u_fcr);

	/* Clear modem control register */
	writeb(0, &uart->i4u_mcr);

	/* Clear deltas in modem status register */
	readb(&uart->i4u_msr);

	/* Only do this once per port pair */
	if (port->ip_hooks == &hooks_array[0]
			    || port->ip_hooks == &hooks_array[2]) {
		unsigned long ring_pci_addr;
		uint32_t __iomem *sbbr_l;
		uint32_t __iomem *sbbr_h;

		if (port->ip_hooks == &hooks_array[0]) {
			sbbr_l = &port->ip_serial->sbbr01_l;
			sbbr_h = &port->ip_serial->sbbr01_h;
		} else {
			sbbr_l = &port->ip_serial->sbbr23_l;
			sbbr_h = &port->ip_serial->sbbr23_h;
		}

		ring_pci_addr = (unsigned long __iomem)port->ip_dma_ringbuf;
		DPRINT_CONFIG(("%s: ring_pci_addr 0x%lx\n",
					__FUNCTION__, ring_pci_addr));

		writel((unsigned int)((uint64_t)ring_pci_addr >> 32), sbbr_h);
		writel((unsigned int)ring_pci_addr | IOC4_BUF_SIZE_BIT, sbbr_l);
	}

	/* Set the receive timeout value to 10 msec */
	writel(IOC4_SRTR_HZ / 100, &port->ip_serial_regs->srtr);

	/* Set rx threshold, enable DMA */
	/* Set high water mark at 3/4 of full ring */
	port->ip_sscr = (ENTRIES_PER_RING * 3 / 4);
	writel(port->ip_sscr, &port->ip_serial_regs->sscr);

	/* Disable and clear all serial related interrupt bits */
	write_ireg(port->ip_ioc4_soft, hooks->intr_clear,
		       IOC4_W_IEC, IOC4_SIO_INTR_TYPE);
	port->ip_ienb &= ~hooks->intr_clear;
	writel(hooks->intr_clear, &port->ip_mem->sio_ir.raw);
	return 0;
}

/**
 * handle_dma_error_intr - service any pending DMA error interrupts for the
 *			given port - 2nd level called via sd_intr
 * @arg: handler arg
 * @other_ir: ioc4regs
 */
static void handle_dma_error_intr(void *arg, uint32_t other_ir)
{
	struct ioc4_port *port = (struct ioc4_port *)arg;
	struct hooks *hooks = port->ip_hooks;
	unsigned int flags;

	spin_lock_irqsave(&port->ip_lock, flags);

	/* ACK the interrupt */
	writel(hooks->intr_dma_error, &port->ip_mem->other_ir.raw);

	if (readl(&port->ip_mem->pci_err_addr_l.raw) & IOC4_PCI_ERR_ADDR_VLD) {
		printk(KERN_ERR
			"PCI error address is 0x%lx, "
				"master is serial port %c %s\n",
		     (((uint64_t)readl(&port->ip_mem->pci_err_addr_h)
							 << 32)
				| readl(&port->ip_mem->pci_err_addr_l.raw))
					& IOC4_PCI_ERR_ADDR_ADDR_MSK, '1' +
		     ((char)(readl(&port->ip_mem->pci_err_addr_l.raw) &
			     IOC4_PCI_ERR_ADDR_MST_NUM_MSK) >> 1),
		     (readl(&port->ip_mem->pci_err_addr_l.raw)
				& IOC4_PCI_ERR_ADDR_MST_TYP_MSK)
				? "RX" : "TX");

		if (readl(&port->ip_mem->pci_err_addr_l.raw)
						& IOC4_PCI_ERR_ADDR_MUL_ERR) {
			printk(KERN_ERR
				"Multiple errors occurred\n");
		}
	}
	spin_unlock_irqrestore(&port->ip_lock, flags);

	/* Re-enable DMA error interrupts */
	write_ireg(port->ip_ioc4_soft, hooks->intr_dma_error, IOC4_W_IES,
						IOC4_OTHER_INTR_TYPE);
}

/**
 * intr_connect - interrupt connect function
 * @soft: soft struct for this card
 * @type: interrupt type
 * @intrbits: bit pattern to set
 * @intr: handler function
 * @info: handler arg
 */
static void
intr_connect(struct ioc4_soft *soft, int type,
		  uint32_t intrbits, ioc4_intr_func_f * intr, void *info)
{
	int i;
	struct ioc4_intr_info *intr_ptr;

	BUG_ON(!((type == IOC4_SIO_INTR_TYPE)
	       || (type == IOC4_OTHER_INTR_TYPE)));

	i = atomic_inc(&soft-> is_intr_type[type].is_num_intrs) - 1;
	BUG_ON(!(i < MAX_IOC4_INTR_ENTS || (printk("i %d\n", i), 0)));

	/* Save off the lower level interrupt handler */
	intr_ptr = &soft->is_intr_type[type].is_intr_info[i];
	intr_ptr->sd_bits = intrbits;
	intr_ptr->sd_intr = intr;
	intr_ptr->sd_info = info;
}

/**
 * ioc4_intr - Top level IOC4 interrupt handler.
 * @irq: irq value
 * @arg: handler arg
 * @regs: registers
 */

static irqreturn_t ioc4_intr(int irq, void *arg, struct pt_regs *regs)
{
	struct ioc4_soft *soft;
	uint32_t this_ir, this_mir;
	int xx, num_intrs = 0;
	int intr_type;
	int handled = 0;
	struct ioc4_intr_info *intr_info;

	soft = arg;
	for (intr_type = 0; intr_type < IOC4_NUM_INTR_TYPES; intr_type++) {
		num_intrs = (int)atomic_read(
				&soft->is_intr_type[intr_type].is_num_intrs);

		this_mir = this_ir = pending_intrs(soft, intr_type);

		/* Farm out the interrupt to the various drivers depending on
		 * which interrupt bits are set.
		 */
		for (xx = 0; xx < num_intrs; xx++) {
			intr_info = &soft->is_intr_type[intr_type].is_intr_info[xx];
			if ((this_mir = this_ir & intr_info->sd_bits)) {
				/* Disable owned interrupts, call handler */
				handled++;
				write_ireg(soft, intr_info->sd_bits, IOC4_W_IEC,
								intr_type);
				intr_info->sd_intr(intr_info->sd_info, this_mir);
				this_ir &= ~this_mir;
			}
		}
	}
#ifdef DEBUG_INTERRUPTS
	{
		struct ioc4_misc_regs __iomem *mem = soft->is_ioc4_misc_addr;
		unsigned long flag;

		spin_lock_irqsave(&soft->is_ir_lock, flag);
		printk ("%s : %d : mem 0x%p sio_ir 0x%x sio_ies 0x%x "
				"other_ir 0x%x other_ies 0x%x mask 0x%x\n",
		     __FUNCTION__, __LINE__,
		     (void *)mem, readl(&mem->sio_ir.raw),
		     readl(&mem->sio_ies.raw),
		     readl(&mem->other_ir.raw),
		     readl(&mem->other_ies.raw),
		     IOC4_OTHER_IR_ATA_INT | IOC4_OTHER_IR_ATA_MEMERR);
		spin_unlock_irqrestore(&soft->is_ir_lock, flag);
	}
#endif
	return handled ? IRQ_HANDLED : IRQ_NONE;
}

/**
 * ioc4_attach_local - Device initialization.
 *			Called at *_attach() time for each
 *			IOC4 with serial ports in the system.
 * @idd: Master module data for this IOC4
 */
static int inline ioc4_attach_local(struct ioc4_driver_data *idd)
{
	struct ioc4_port *port;
	struct ioc4_port *ports[IOC4_NUM_SERIAL_PORTS];
	int port_number;
	uint16_t ioc4_revid_min = 62;
	uint16_t ioc4_revid;
	struct pci_dev *pdev = idd->idd_pdev;
	struct ioc4_control* control = idd->idd_serial_data;
	struct ioc4_soft *soft = control->ic_soft;
	void __iomem *ioc4_misc = idd->idd_misc_regs;
	void __iomem *ioc4_serial = soft->is_ioc4_serial_addr;

	/* IOC4 firmware must be at least rev 62 */
	pci_read_config_word(pdev, PCI_COMMAND_SPECIAL, &ioc4_revid);

	printk(KERN_INFO "IOC4 firmware revision %d\n", ioc4_revid);
	if (ioc4_revid < ioc4_revid_min) {
		printk(KERN_WARNING
		    "IOC4 serial not supported on firmware rev %d, "
				"please upgrade to rev %d or higher\n",
				ioc4_revid, ioc4_revid_min);
		return -EPERM;
	}
	BUG_ON(ioc4_misc == NULL);
	BUG_ON(ioc4_serial == NULL);

	/* Create port structures for each port */
	for (port_number = 0; port_number < IOC4_NUM_SERIAL_PORTS;
							port_number++) {
		port = kmalloc(sizeof(struct ioc4_port), GFP_KERNEL);
		if (!port) {
			printk(KERN_WARNING
				"IOC4 serial memory not available for port\n");
			return -ENOMEM;
		}
		memset(port, 0, sizeof(struct ioc4_port));
		spin_lock_init(&port->ip_lock);

		/* we need to remember the previous ones, to point back to
		 * them farther down - setting up the ring buffers.
		 */
		ports[port_number] = port;

		/* Allocate buffers and jumpstart the hardware.  */
		control->ic_port[port_number].icp_port = port;
		port->ip_ioc4_soft = soft;
		port->ip_pdev = pdev;
		port->ip_ienb = 0;
		/* Use baud rate calculations based on detected PCI
		 * bus speed.  Simply test whether the PCI clock is
		 * running closer to 66MHz or 33MHz.
		 */
		if (idd->count_period/IOC4_EXTINT_COUNT_DIVISOR < 20) {
			port->ip_pci_bus_speed = IOC4_SER_XIN_CLK_66;
		} else {
			port->ip_pci_bus_speed = IOC4_SER_XIN_CLK_33;
		}
		port->ip_baud = 9600;
		port->ip_control = control;
		port->ip_mem = ioc4_misc;
		port->ip_serial = ioc4_serial;

		/* point to the right hook */
		port->ip_hooks = &hooks_array[port_number];

		/* Get direct hooks to the serial regs and uart regs
		 * for this port
		 */
		switch (port_number) {
		case 0:
			port->ip_serial_regs = &(port->ip_serial->port_0);
			port->ip_uart_regs = &(port->ip_serial->uart_0);
			break;
		case 1:
			port->ip_serial_regs = &(port->ip_serial->port_1);
			port->ip_uart_regs = &(port->ip_serial->uart_1);
			break;
		case 2:
			port->ip_serial_regs = &(port->ip_serial->port_2);
			port->ip_uart_regs = &(port->ip_serial->uart_2);
			break;
		default:
		case 3:
			port->ip_serial_regs = &(port->ip_serial->port_3);
			port->ip_uart_regs = &(port->ip_serial->uart_3);
			break;
		}

		/* ring buffers are 1 to a pair of ports */
		if (port_number && (port_number & 1)) {
			/* odd use the evens buffer */
			port->ip_dma_ringbuf =
					ports[port_number - 1]->ip_dma_ringbuf;
			port->ip_cpu_ringbuf =
					ports[port_number - 1]->ip_cpu_ringbuf;
			port->ip_inring = RING(port, RX_1_OR_3);
			port->ip_outring = RING(port, TX_1_OR_3);

		} else {
			if (port->ip_dma_ringbuf == 0) {
				port->ip_cpu_ringbuf = pci_alloc_consistent
					(pdev, TOTAL_RING_BUF_SIZE,
					&port->ip_dma_ringbuf);

			}
			BUG_ON(!((((int64_t)port->ip_dma_ringbuf) &
				(TOTAL_RING_BUF_SIZE - 1)) == 0));
			DPRINT_CONFIG(("%s : ip_cpu_ringbuf 0x%p "
						"ip_dma_ringbuf 0x%p\n",
					__FUNCTION__,
					(void *)port->ip_cpu_ringbuf,
					(void *)port->ip_dma_ringbuf));
			port->ip_inring = RING(port, RX_0_OR_2);
			port->ip_outring = RING(port, TX_0_OR_2);
		}
		DPRINT_CONFIG(("%s : port %d [addr 0x%p] control 0x%p",
				__FUNCTION__,
				port_number, (void *)port, (void *)control));
		DPRINT_CONFIG((" ip_serial_regs 0x%p ip_uart_regs 0x%p\n",
				(void *)port->ip_serial_regs,
				(void *)port->ip_uart_regs));

		/* Initialize the hardware for IOC4 */
		port_init(port);

		DPRINT_CONFIG(("%s: port_number %d port 0x%p inring 0x%p "
						"outring 0x%p\n",
				__FUNCTION__,
				port_number, (void *)port,
				(void *)port->ip_inring,
				(void *)port->ip_outring));

		/* Attach interrupt handlers */
		intr_connect(soft, IOC4_SIO_INTR_TYPE,
				GET_SIO_IR(port_number),
				handle_intr, port);

		intr_connect(soft, IOC4_OTHER_INTR_TYPE,
				GET_OTHER_IR(port_number),
				handle_dma_error_intr, port);
	}
	return 0;
}

/**
 * enable_intrs - enable interrupts
 * @port: port to enable
 * @mask: mask to use
 */
static void enable_intrs(struct ioc4_port *port, uint32_t mask)
{
	struct hooks *hooks = port->ip_hooks;

	if ((port->ip_ienb & mask) != mask) {
		write_ireg(port->ip_ioc4_soft, mask, IOC4_W_IES,
						IOC4_SIO_INTR_TYPE);
		port->ip_ienb |= mask;
	}

	if (port->ip_ienb)
		write_ireg(port->ip_ioc4_soft, hooks->intr_dma_error,
				IOC4_W_IES, IOC4_OTHER_INTR_TYPE);
}

/**
 * local_open - local open a port
 * @port: port to open
 */
static inline int local_open(struct ioc4_port *port)
{
	int spiniter = 0;

	port->ip_flags = PORT_ACTIVE;

	/* Pause the DMA interface if necessary */
	if (port->ip_sscr & IOC4_SSCR_DMA_EN) {
		writel(port->ip_sscr | IOC4_SSCR_DMA_PAUSE,
			&port->ip_serial_regs->sscr);
		while((readl(&port->ip_serial_regs-> sscr)
				& IOC4_SSCR_PAUSE_STATE) == 0) {
			spiniter++;
			if (spiniter > MAXITER) {
				port->ip_flags = PORT_INACTIVE;
				return -1;
			}
		}
	}

	/* Reset the input fifo.  If the uart received chars while the port
	 * was closed and DMA is not enabled, the uart may have a bunch of
	 * chars hanging around in its rx fifo which will not be discarded
	 * by rclr in the upper layer. We must get rid of them here.
	 */
	writeb(UART_FCR_ENABLE_FIFO | UART_FCR_CLEAR_RCVR,
				&port->ip_uart_regs->i4u_fcr);

	writeb(UART_LCR_WLEN8, &port->ip_uart_regs->i4u_lcr);
					/* UART_LCR_STOP == 1 stop */

	/* Re-enable DMA, set default threshold to intr whenever there is
	 * data available.
	 */
	port->ip_sscr &= ~IOC4_SSCR_RX_THRESHOLD;
	port->ip_sscr |= 1;	/* default threshold */

	/* Plug in the new sscr.  This implicitly clears the DMA_PAUSE
	 * flag if it was set above
	 */
	writel(port->ip_sscr, &port->ip_serial_regs->sscr);
	port->ip_tx_lowat = 1;
	return 0;
}

/**
 * set_rx_timeout - Set rx timeout and threshold values.
 * @port: port to use
 * @timeout: timeout value in ticks
 */
static inline int set_rx_timeout(struct ioc4_port *port, int timeout)
{
	int threshold;

	port->ip_rx_timeout = timeout;

	/* Timeout is in ticks.  Let's figure out how many chars we
	 * can receive at the current baud rate in that interval
	 * and set the rx threshold to that amount.  There are 4 chars
	 * per ring entry, so we'll divide the number of chars that will
	 * arrive in timeout by 4.
	 * So .... timeout * baud / 10 / HZ / 4, with HZ = 100.
	 */
	threshold = timeout * port->ip_baud / 4000;
	if (threshold == 0)
		threshold = 1;	/* otherwise we'll intr all the time! */

	if ((unsigned)threshold > (unsigned)IOC4_SSCR_RX_THRESHOLD)
		return 1;

	port->ip_sscr &= ~IOC4_SSCR_RX_THRESHOLD;
	port->ip_sscr |= threshold;

	writel(port->ip_sscr, &port->ip_serial_regs->sscr);

	/* Now set the rx timeout to the given value
	 * again timeout * IOC4_SRTR_HZ / HZ
	 */
	timeout = timeout * IOC4_SRTR_HZ / 100;
	if (timeout > IOC4_SRTR_CNT)
		timeout = IOC4_SRTR_CNT;

	writel(timeout, &port->ip_serial_regs->srtr);
	return 0;
}

/**
 * config_port - config the hardware
 * @port: port to config
 * @baud: baud rate for the port
 * @byte_size: data size
 * @stop_bits: number of stop bits
 * @parenb: parity enable ?
 * @parodd: odd parity ?
 */
static inline int
config_port(struct ioc4_port *port,
	    int baud, int byte_size, int stop_bits, int parenb, int parodd)
{
	char lcr, sizebits;
	int spiniter = 0;

	DPRINT_CONFIG(("%s: baud %d byte_size %d stop %d parenb %d parodd %d\n",
		__FUNCTION__, baud, byte_size, stop_bits, parenb, parodd));

	if (set_baud(port, baud))
		return 1;

	switch (byte_size) {
	case 5:
		sizebits = UART_LCR_WLEN5;
		break;
	case 6:
		sizebits = UART_LCR_WLEN6;
		break;
	case 7:
		sizebits = UART_LCR_WLEN7;
		break;
	case 8:
		sizebits = UART_LCR_WLEN8;
		break;
	default:
		return 1;
	}

	/* Pause the DMA interface if necessary */
	if (port->ip_sscr & IOC4_SSCR_DMA_EN) {
		writel(port->ip_sscr | IOC4_SSCR_DMA_PAUSE,
			&port->ip_serial_regs->sscr);
		while((readl(&port->ip_serial_regs->sscr)
						& IOC4_SSCR_PAUSE_STATE) == 0) {
			spiniter++;
			if (spiniter > MAXITER)
				return -1;
		}
	}

	/* Clear relevant fields in lcr */
	lcr = readb(&port->ip_uart_regs->i4u_lcr);
	lcr &= ~(LCR_MASK_BITS_CHAR | UART_LCR_EPAR |
		 UART_LCR_PARITY | LCR_MASK_STOP_BITS);

	/* Set byte size in lcr */
	lcr |= sizebits;

	/* Set parity */
	if (parenb) {
		lcr |= UART_LCR_PARITY;
		if (!parodd)
			lcr |= UART_LCR_EPAR;
	}

	/* Set stop bits */
	if (stop_bits)
		lcr |= UART_LCR_STOP /* 2 stop bits */ ;

	writeb(lcr, &port->ip_uart_regs->i4u_lcr);

	/* Re-enable the DMA interface if necessary */
	if (port->ip_sscr & IOC4_SSCR_DMA_EN) {
		writel(port->ip_sscr, &port->ip_serial_regs->sscr);
	}
	port->ip_baud = baud;

	/* When we get within this number of ring entries of filling the
	 * entire ring on tx, place an EXPLICIT intr to generate a lowat
	 * notification when output has drained.
	 */
	port->ip_tx_lowat = (TX_LOWAT_CHARS(baud) + 3) / 4;
	if (port->ip_tx_lowat == 0)
		port->ip_tx_lowat = 1;

	set_rx_timeout(port, 2);

	return 0;
}

/**
 * do_write - Write bytes to the port.  Returns the number of bytes
 *			actually written. Called from transmit_chars
 * @port: port to use
 * @buf: the stuff to write
 * @len: how many bytes in 'buf'
 */
static inline int do_write(struct ioc4_port *port, char *buf, int len)
{
	int prod_ptr, cons_ptr, total = 0;
	struct ring *outring;
	struct ring_entry *entry;
	struct hooks *hooks = port->ip_hooks;

	BUG_ON(!(len >= 0));

	prod_ptr = port->ip_tx_prod;
	cons_ptr = readl(&port->ip_serial_regs->stcir) & PROD_CONS_MASK;
	outring = port->ip_outring;

	/* Maintain a 1-entry red-zone.  The ring buffer is full when
	 * (cons - prod) % ring_size is 1.  Rather than do this subtraction
	 * in the body of the loop, I'll do it now.
	 */
	cons_ptr = (cons_ptr - (int)sizeof(struct ring_entry)) & PROD_CONS_MASK;

	/* Stuff the bytes into the output */
	while ((prod_ptr != cons_ptr) && (len > 0)) {
		int xx;

		/* Get 4 bytes (one ring entry) at a time */
		entry = (struct ring_entry *)((caddr_t) outring + prod_ptr);

		/* Invalidate all entries */
		entry->ring_allsc = 0;

		/* Copy in some bytes */
		for (xx = 0; (xx < 4) && (len > 0); xx++) {
			entry->ring_data[xx] = *buf++;
			entry->ring_sc[xx] = IOC4_TXCB_VALID;
			len--;
			total++;
		}

		/* If we are within some small threshold of filling up the
		 * entire ring buffer, we must place an EXPLICIT intr here
		 * to generate a lowat interrupt in case we subsequently
		 * really do fill up the ring and the caller goes to sleep.
		 * No need to place more than one though.
		 */
		if (!(port->ip_flags & LOWAT_WRITTEN) &&
			((cons_ptr - prod_ptr) & PROD_CONS_MASK)
				<= port->ip_tx_lowat
					* (int)sizeof(struct ring_entry)) {
			port->ip_flags |= LOWAT_WRITTEN;
			entry->ring_sc[0] |= IOC4_TXCB_INT_WHEN_DONE;
		}

		/* Go on to next entry */
		prod_ptr += sizeof(struct ring_entry);
		prod_ptr &= PROD_CONS_MASK;
	}

	/* If we sent something, start DMA if necessary */
	if (total > 0 && !(port->ip_sscr & IOC4_SSCR_DMA_EN)) {
		port->ip_sscr |= IOC4_SSCR_DMA_EN;
		writel(port->ip_sscr, &port->ip_serial_regs->sscr);
	}

	/* Store the new producer pointer.  If tx is disabled, we stuff the
	 * data into the ring buffer, but we don't actually start tx.
	 */
	if (!uart_tx_stopped(port->ip_port)) {
		writel(prod_ptr, &port->ip_serial_regs->stpir);

		/* If we are now transmitting, enable tx_mt interrupt so we
		 * can disable DMA if necessary when the tx finishes.
		 */
		if (total > 0)
			enable_intrs(port, hooks->intr_tx_mt);
	}
	port->ip_tx_prod = prod_ptr;
	return total;
}

/**
 * disable_intrs - disable interrupts
 * @port: port to enable
 * @mask: mask to use
 */
static void disable_intrs(struct ioc4_port *port, uint32_t mask)
{
	struct hooks *hooks = port->ip_hooks;

	if (port->ip_ienb & mask) {
		write_ireg(port->ip_ioc4_soft, mask, IOC4_W_IEC,
					IOC4_SIO_INTR_TYPE);
		port->ip_ienb &= ~mask;
	}

	if (!port->ip_ienb)
		write_ireg(port->ip_ioc4_soft, hooks->intr_dma_error,
				IOC4_W_IEC, IOC4_OTHER_INTR_TYPE);
}

/**
 * set_notification - Modify event notification
 * @port: port to use
 * @mask: events mask
 * @set_on: set ?
 */
static int set_notification(struct ioc4_port *port, int mask, int set_on)
{
	struct hooks *hooks = port->ip_hooks;
	uint32_t intrbits, sscrbits;

	BUG_ON(!mask);

	intrbits = sscrbits = 0;

	if (mask & N_DATA_READY)
		intrbits |= (hooks->intr_rx_timer | hooks->intr_rx_high);
	if (mask & N_OUTPUT_LOWAT)
		intrbits |= hooks->intr_tx_explicit;
	if (mask & N_DDCD) {
		intrbits |= hooks->intr_delta_dcd;
		sscrbits |= IOC4_SSCR_RX_RING_DCD;
	}
	if (mask & N_DCTS)
		intrbits |= hooks->intr_delta_cts;

	if (set_on) {
		enable_intrs(port, intrbits);
		port->ip_notify |= mask;
		port->ip_sscr |= sscrbits;
	} else {
		disable_intrs(port, intrbits);
		port->ip_notify &= ~mask;
		port->ip_sscr &= ~sscrbits;
	}

	/* We require DMA if either DATA_READY or DDCD notification is
	 * currently requested. If neither of these is requested and
	 * there is currently no tx in progress, DMA may be disabled.
	 */
	if (port->ip_notify & (N_DATA_READY | N_DDCD))
		port->ip_sscr |= IOC4_SSCR_DMA_EN;
	else if (!(port->ip_ienb & hooks->intr_tx_mt))
		port->ip_sscr &= ~IOC4_SSCR_DMA_EN;

	writel(port->ip_sscr, &port->ip_serial_regs->sscr);
	return 0;
}

/**
 * set_mcr - set the master control reg
 * @the_port: port to use
 * @mask1: mcr mask
 * @mask2: shadow mask
 */
static inline int set_mcr(struct uart_port *the_port,
		int mask1, int mask2)
{
	struct ioc4_port *port = get_ioc4_port(the_port, 0);
	uint32_t shadow;
	int spiniter = 0;
	char mcr;

	if (!port)
		return -1;

	/* Pause the DMA interface if necessary */
	if (port->ip_sscr & IOC4_SSCR_DMA_EN) {
		writel(port->ip_sscr | IOC4_SSCR_DMA_PAUSE,
			&port->ip_serial_regs->sscr);
		while ((readl(&port->ip_serial_regs->sscr)
					& IOC4_SSCR_PAUSE_STATE) == 0) {
			spiniter++;
			if (spiniter > MAXITER)
				return -1;
		}
	}
	shadow = readl(&port->ip_serial_regs->shadow);
	mcr = (shadow & 0xff000000) >> 24;

	/* Set new value */
	mcr |= mask1;
	shadow |= mask2;

	writeb(mcr, &port->ip_uart_regs->i4u_mcr);
	writel(shadow, &port->ip_serial_regs->shadow);

	/* Re-enable the DMA interface if necessary */
	if (port->ip_sscr & IOC4_SSCR_DMA_EN) {
		writel(port->ip_sscr, &port->ip_serial_regs->sscr);
	}
	return 0;
}

/**
 * ioc4_set_proto - set the protocol for the port
 * @port: port to use
 * @proto: protocol to use
 */
static int ioc4_set_proto(struct ioc4_port *port, int proto)
{
	struct hooks *hooks = port->ip_hooks;

	switch (proto) {
	case PROTO_RS232:
		/* Clear the appropriate GIO pin */
		writel(0, (&port->ip_mem->gppr[hooks->rs422_select_pin].raw));
		break;

	case PROTO_RS422:
		/* Set the appropriate GIO pin */
		writel(1, (&port->ip_mem->gppr[hooks->rs422_select_pin].raw));
		break;

	default:
		return 1;
	}
	return 0;
}

/**
 * transmit_chars - upper level write, called with ip_lock
 * @the_port: port to write
 */
static void transmit_chars(struct uart_port *the_port)
{
	int xmit_count, tail, head;
	int result;
	char *start;
	struct tty_struct *tty;
	struct ioc4_port *port = get_ioc4_port(the_port, 0);
	struct uart_info *info;

	if (!the_port)
		return;
	if (!port)
		return;

	info = the_port->info;
	tty = info->tty;

	if (uart_circ_empty(&info->xmit) || uart_tx_stopped(the_port)) {
		/* Nothing to do or hw stopped */
		set_notification(port, N_ALL_OUTPUT, 0);
		return;
	}

	head = info->xmit.head;
	tail = info->xmit.tail;
	start = (char *)&info->xmit.buf[tail];

	/* write out all the data or until the end of the buffer */
	xmit_count = (head < tail) ? (UART_XMIT_SIZE - tail) : (head - tail);
	if (xmit_count > 0) {
		result = do_write(port, start, xmit_count);
		if (result > 0) {
			/* booking */
			xmit_count -= result;
			the_port->icount.tx += result;
			/* advance the pointers */
			tail += result;
			tail &= UART_XMIT_SIZE - 1;
			info->xmit.tail = tail;
			start = (char *)&info->xmit.buf[tail];
		}
	}
	if (uart_circ_chars_pending(&info->xmit) < WAKEUP_CHARS)
		uart_write_wakeup(the_port);

	if (uart_circ_empty(&info->xmit)) {
		set_notification(port, N_OUTPUT_LOWAT, 0);
	} else {
		set_notification(port, N_OUTPUT_LOWAT, 1);
	}
}

/**
 * ioc4_change_speed - change the speed of the port
 * @the_port: port to change
 * @new_termios: new termios settings
 * @old_termios: old termios settings
 */
static void
ioc4_change_speed(struct uart_port *the_port,
		  struct termios *new_termios, struct termios *old_termios)
{
	struct ioc4_port *port = get_ioc4_port(the_port, 0);
	int baud, bits;
	unsigned cflag;
	int new_parity = 0, new_parity_enable = 0, new_stop = 0, new_data = 8;
	struct uart_info *info = the_port->info;

	cflag = new_termios->c_cflag;

	switch (cflag & CSIZE) {
	case CS5:
		new_data = 5;
		bits = 7;
		break;
	case CS6:
		new_data = 6;
		bits = 8;
		break;
	case CS7:
		new_data = 7;
		bits = 9;
		break;
	case CS8:
		new_data = 8;
		bits = 10;
		break;
	default:
		/* cuz we always need a default ... */
		new_data = 5;
		bits = 7;
		break;
	}
	if (cflag & CSTOPB) {
		bits++;
		new_stop = 1;
	}
	if (cflag & PARENB) {
		bits++;
		new_parity_enable = 1;
		if (cflag & PARODD)
			new_parity = 1;
	}
	baud = uart_get_baud_rate(the_port, new_termios, old_termios,
				MIN_BAUD_SUPPORTED, MAX_BAUD_SUPPORTED);
	DPRINT_CONFIG(("%s: returned baud %d\n", __FUNCTION__, baud));

	/* default is 9600 */
	if (!baud)
		baud = 9600;

	if (!the_port->fifosize)
		the_port->fifosize = IOC4_FIFO_CHARS;
	the_port->timeout = ((the_port->fifosize * HZ * bits) / (baud / 10));
	the_port->timeout += HZ / 50;	/* Add .02 seconds of slop */

	the_port->ignore_status_mask = N_ALL_INPUT;

	info->tty->low_latency = 1;

	if (I_IGNPAR(info->tty))
		the_port->ignore_status_mask &= ~(N_PARITY_ERROR
						| N_FRAMING_ERROR);
	if (I_IGNBRK(info->tty)) {
		the_port->ignore_status_mask &= ~N_BREAK;
		if (I_IGNPAR(info->tty))
			the_port->ignore_status_mask &= ~N_OVERRUN_ERROR;
	}
	if (!(cflag & CREAD)) {
		/* ignore everything */
		the_port->ignore_status_mask &= ~N_DATA_READY;
	}

	if (cflag & CRTSCTS) {
		port->ip_sscr |= IOC4_SSCR_HFC_EN;
	}
	else {
		port->ip_sscr &= ~IOC4_SSCR_HFC_EN;
	}
	writel(port->ip_sscr, &port->ip_serial_regs->sscr);

	/* Set the configuration and proper notification call */
	DPRINT_CONFIG(("%s : port 0x%p cflag 0%o "
		"config_port(baud %d data %d stop %d p enable %d parity %d),"
		" notification 0x%x\n",
	     __FUNCTION__, (void *)port, cflag, baud, new_data, new_stop,
	     new_parity_enable, new_parity, the_port->ignore_status_mask));

	if ((config_port(port, baud,		/* baud */
			 new_data,		/* byte size */
			 new_stop,		/* stop bits */
			 new_parity_enable,	/* set parity */
			 new_parity)) >= 0) {	/* parity 1==odd */
		set_notification(port, the_port->ignore_status_mask, 1);
	}
}

/**
 * ic4_startup_local - Start up the serial port - returns >= 0 if no errors
 * @the_port: Port to operate on
 */
static inline int ic4_startup_local(struct uart_port *the_port)
{
	struct ioc4_port *port;
	struct uart_info *info;

	if (!the_port)
		return -1;

	port = get_ioc4_port(the_port, 0);
	if (!port)
		return -1;

	info = the_port->info;

	local_open(port);

	/* set the protocol - mapbase has the port type */
	ioc4_set_proto(port, the_port->mapbase);

	/* set the speed of the serial port */
	ioc4_change_speed(the_port, info->tty->termios, (struct termios *)0);

	return 0;
}

/*
 * ioc4_cb_output_lowat - called when the output low water mark is hit
 * @the_port: port to output
 */
static void ioc4_cb_output_lowat(struct uart_port *the_port)
{
	unsigned long pflags;

	/* ip_lock is set on the call here */
	if (the_port) {
		spin_lock_irqsave(&the_port->lock, pflags);
		transmit_chars(the_port);
		spin_unlock_irqrestore(&the_port->lock, pflags);
	}
}

/**
 * handle_intr - service any interrupts for the given port - 2nd level
 *			called via sd_intr
 * @arg: handler arg
 * @sio_ir: ioc4regs
 */
static void handle_intr(void *arg, uint32_t sio_ir)
{
	struct ioc4_port *port = (struct ioc4_port *)arg;
	struct hooks *hooks = port->ip_hooks;
	unsigned int rx_high_rd_aborted = 0;
	unsigned int flags;
	struct uart_port *the_port;
	int loop_counter;

	/* Possible race condition here: The tx_mt interrupt bit may be
	 * cleared without the intervention of the interrupt handler,
	 * e.g. by a write.  If the top level interrupt handler reads a
	 * tx_mt, then some other processor does a write, starting up
	 * output, then we come in here, see the tx_mt and stop DMA, the
	 * output started by the other processor will hang.  Thus we can
	 * only rely on tx_mt being legitimate if it is read while the
	 * port lock is held.  Therefore this bit must be ignored in the
	 * passed in interrupt mask which was read by the top level
	 * interrupt handler since the port lock was not held at the time
	 * it was read.  We can only rely on this bit being accurate if it
	 * is read while the port lock is held.  So we'll clear it for now,
	 * and reload it later once we have the port lock.
	 */
	sio_ir &= ~(hooks->intr_tx_mt);

	spin_lock_irqsave(&port->ip_lock, flags);

	loop_counter = MAXITER;	/* to avoid hangs */

	do {
		uint32_t shadow;

		if ( loop_counter-- <= 0 ) {
			printk(KERN_WARNING "IOC4 serial: "
					"possible hang condition/"
					"port stuck on interrupt.\n");
			break;
		}

		/* Handle a DCD change */
		if (sio_ir & hooks->intr_delta_dcd) {
			/* ACK the interrupt */
			writel(hooks->intr_delta_dcd,
				&port->ip_mem->sio_ir.raw);

			shadow = readl(&port->ip_serial_regs->shadow);

			if ((port->ip_notify & N_DDCD)
					&& (shadow & IOC4_SHADOW_DCD)
					&& (port->ip_port)) {
				the_port = port->ip_port;
				the_port->icount.dcd = 1;
				wake_up_interruptible
					    (&the_port-> info->delta_msr_wait);
			} else if ((port->ip_notify & N_DDCD)
					&& !(shadow & IOC4_SHADOW_DCD)) {
				/* Flag delta DCD/no DCD */
				port->ip_flags |= DCD_ON;
			}
		}

		/* Handle a CTS change */
		if (sio_ir & hooks->intr_delta_cts) {
			/* ACK the interrupt */
			writel(hooks->intr_delta_cts,
					&port->ip_mem->sio_ir.raw);

			shadow = readl(&port->ip_serial_regs->shadow);

			if ((port->ip_notify & N_DCTS)
					&& (port->ip_port)) {
				the_port = port->ip_port;
				the_port->icount.cts =
					(shadow & IOC4_SHADOW_CTS) ? 1 : 0;
				wake_up_interruptible
					(&the_port->info->delta_msr_wait);
			}
		}

		/* rx timeout interrupt.  Must be some data available.  Put this
		 * before the check for rx_high since servicing this condition
		 * may cause that condition to clear.
		 */
		if (sio_ir & hooks->intr_rx_timer) {
			/* ACK the interrupt */
			writel(hooks->intr_rx_timer,
				&port->ip_mem->sio_ir.raw);

			if ((port->ip_notify & N_DATA_READY)
					&& (port->ip_port)) {
				/* ip_lock is set on call here */
				receive_chars(port->ip_port);
			}
		}

		/* rx high interrupt. Must be after rx_timer.  */
		else if (sio_ir & hooks->intr_rx_high) {
			/* Data available, notify upper layer */
			if ((port->ip_notify & N_DATA_READY)
						&& port->ip_port) {
				/* ip_lock is set on call here */
				receive_chars(port->ip_port);
			}

			/* We can't ACK this interrupt.  If receive_chars didn't
			 * cause the condition to clear, we'll have to disable
			 * the interrupt until the data is drained.
			 * If the read was aborted, don't disable the interrupt
			 * as this may cause us to hang indefinitely.  An
			 * aborted read generally means that this interrupt
			 * hasn't been delivered to the cpu yet anyway, even
			 * though we see it as asserted when we read the sio_ir.
			 */
			if ((sio_ir = PENDING(port)) & hooks->intr_rx_high) {
				if ((port->ip_flags & READ_ABORTED) == 0) {
					port->ip_ienb &= ~hooks->intr_rx_high;
					port->ip_flags |= INPUT_HIGH;
				} else {
					rx_high_rd_aborted++;
				}
			}
		}

		/* We got a low water interrupt: notify upper layer to
		 * send more data.  Must come before tx_mt since servicing
		 * this condition may cause that condition to clear.
		 */
		if (sio_ir & hooks->intr_tx_explicit) {
			port->ip_flags &= ~LOWAT_WRITTEN;

			/* ACK the interrupt */
			writel(hooks->intr_tx_explicit,
					&port->ip_mem->sio_ir.raw);

			if (port->ip_notify & N_OUTPUT_LOWAT)
				ioc4_cb_output_lowat(port->ip_port);
		}

		/* Handle tx_mt.  Must come after tx_explicit.  */
		else if (sio_ir & hooks->intr_tx_mt) {
			/* If we are expecting a lowat notification
			 * and we get to this point it probably means that for
			 * some reason the tx_explicit didn't work as expected
			 * (that can legitimately happen if the output buffer is
			 * filled up in just the right way).
			 * So send the notification now.
			 */
			if (port->ip_notify & N_OUTPUT_LOWAT) {
				ioc4_cb_output_lowat(port->ip_port);

				/* We need to reload the sio_ir since the lowat
				 * call may have caused another write to occur,
				 * clearing the tx_mt condition.
				 */
				sio_ir = PENDING(port);
			}

			/* If the tx_mt condition still persists even after the
			 * lowat call, we've got some work to do.
			 */
			if (sio_ir & hooks->intr_tx_mt) {

				/* If we are not currently expecting DMA input,
				 * and the transmitter has just gone idle,
				 * there is no longer any reason for DMA, so
				 * disable it.
				 */
				if (!(port->ip_notify
						& (N_DATA_READY | N_DDCD))) {
					BUG_ON(!(port->ip_sscr
							& IOC4_SSCR_DMA_EN));
					port->ip_sscr &= ~IOC4_SSCR_DMA_EN;
					writel(port->ip_sscr,
					   &port->ip_serial_regs->sscr);
				}

				/* Prevent infinite tx_mt interrupt */
				port->ip_ienb &= ~hooks->intr_tx_mt;
			}
		}
		sio_ir = PENDING(port);

		/* if the read was aborted and only hooks->intr_rx_high,
		 * clear hooks->intr_rx_high, so we do not loop forever.
		 */

		if (rx_high_rd_aborted && (sio_ir == hooks->intr_rx_high)) {
			sio_ir &= ~hooks->intr_rx_high;
		}
	} while (sio_ir & hooks->intr_all);

	spin_unlock_irqrestore(&port->ip_lock, flags);

	/* Re-enable interrupts before returning from interrupt handler.
	 * Getting interrupted here is okay.  It'll just v() our semaphore, and
	 * we'll come through the loop again.
	 */

	write_ireg(port->ip_ioc4_soft, port->ip_ienb, IOC4_W_IES,
							IOC4_SIO_INTR_TYPE);
}

/*
 * ioc4_cb_post_ncs - called for some basic errors
 * @port: port to use
 * @ncs: event
 */
static void ioc4_cb_post_ncs(struct uart_port *the_port, int ncs)
{
	struct uart_icount *icount;

	icount = &the_port->icount;

	if (ncs & NCS_BREAK)
		icount->brk++;
	if (ncs & NCS_FRAMING)
		icount->frame++;
	if (ncs & NCS_OVERRUN)
		icount->overrun++;
	if (ncs & NCS_PARITY)
		icount->parity++;
}

/**
 * do_read - Read in bytes from the port.  Return the number of bytes
 *			actually read.
 * @the_port: port to use
 * @buf: place to put the stuff we read
 * @len: how big 'buf' is
 */

static inline int do_read(struct uart_port *the_port, unsigned char *buf,
				int len)
{
	int prod_ptr, cons_ptr, total;
	struct ioc4_port *port = get_ioc4_port(the_port, 0);
	struct ring *inring;
	struct ring_entry *entry;
	struct hooks *hooks = port->ip_hooks;
	int byte_num;
	char *sc;
	int loop_counter;

	BUG_ON(!(len >= 0));
	BUG_ON(!port);

	/* There is a nasty timing issue in the IOC4. When the rx_timer
	 * expires or the rx_high condition arises, we take an interrupt.
	 * At some point while servicing the interrupt, we read bytes from
	 * the ring buffer and re-arm the rx_timer.  However the rx_timer is
	 * not started until the first byte is received *after* it is armed,
	 * and any bytes pending in the rx construction buffers are not drained
	 * to memory until either there are 4 bytes available or the rx_timer
	 * expires.  This leads to a potential situation where data is left
	 * in the construction buffers forever - 1 to 3 bytes were received
	 * after the interrupt was generated but before the rx_timer was
	 * re-armed. At that point as long as no subsequent bytes are received
	 * the timer will never be started and the bytes will remain in the
	 * construction buffer forever.  The solution is to execute a DRAIN
	 * command after rearming the timer.  This way any bytes received before
	 * the DRAIN will be drained to memory, and any bytes received after
	 * the DRAIN will start the TIMER and be drained when it expires.
	 * Luckily, this only needs to be done when the DMA buffer is empty
	 * since there is no requirement that this function return all
	 * available data as long as it returns some.
	 */
	/* Re-arm the timer */
	writel(port->ip_rx_cons | IOC4_SRCIR_ARM, &port->ip_serial_regs->srcir);

	prod_ptr = readl(&port->ip_serial_regs->srpir) & PROD_CONS_MASK;
	cons_ptr = port->ip_rx_cons;

	if (prod_ptr == cons_ptr) {
		int reset_dma = 0;

		/* Input buffer appears empty, do a flush. */

		/* DMA must be enabled for this to work. */
		if (!(port->ip_sscr & IOC4_SSCR_DMA_EN)) {
			port->ip_sscr |= IOC4_SSCR_DMA_EN;
			reset_dma = 1;
		}

		/* Potential race condition: we must reload the srpir after
		 * issuing the drain command, otherwise we could think the rx
		 * buffer is empty, then take a very long interrupt, and when
		 * we come back it's full and we wait forever for the drain to
		 * complete.
		 */
		writel(port->ip_sscr | IOC4_SSCR_RX_DRAIN,
				&port->ip_serial_regs->sscr);
		prod_ptr = readl(&port->ip_serial_regs->srpir)
				& PROD_CONS_MASK;

		/* We must not wait for the DRAIN to complete unless there are
		 * at least 8 bytes (2 ring entries) available to receive the
		 * data otherwise the DRAIN will never complete and we'll
		 * deadlock here.
		 * In fact, to make things easier, I'll just ignore the flush if
		 * there is any data at all now available.
		 */
		if (prod_ptr == cons_ptr) {
			loop_counter = 0;
			while (readl(&port->ip_serial_regs->sscr) &
						IOC4_SSCR_RX_DRAIN) {
				loop_counter++;
				if (loop_counter > MAXITER)
					return -1;
			}

			/* SIGH. We have to reload the prod_ptr *again* since
			 * the drain may have caused it to change
			 */
			prod_ptr = readl(&port->ip_serial_regs->srpir)
							& PROD_CONS_MASK;
		}
		if (reset_dma) {
			port->ip_sscr &= ~IOC4_SSCR_DMA_EN;
			writel(port->ip_sscr, &port->ip_serial_regs->sscr);
		}
	}
	inring = port->ip_inring;
	port->ip_flags &= ~READ_ABORTED;

	total = 0;
	loop_counter = 0xfffff;	/* to avoid hangs */

	/* Grab bytes from the hardware */
	while ((prod_ptr != cons_ptr) && (len > 0)) {
		entry = (struct ring_entry *)((caddr_t)inring + cons_ptr);

		if ( loop_counter-- <= 0 ) {
			printk(KERN_WARNING "IOC4 serial: "
					"possible hang condition/"
					"port stuck on read.\n");
			break;
		}

		/* According to the producer pointer, this ring entry
		 * must contain some data.  But if the PIO happened faster
		 * than the DMA, the data may not be available yet, so let's
		 * wait until it arrives.
		 */
		if ((entry->ring_allsc & RING_ANY_VALID) == 0) {
			/* Indicate the read is aborted so we don't disable
			 * the interrupt thinking that the consumer is
			 * congested.
			 */
			port->ip_flags |= READ_ABORTED;
			len = 0;
			break;
		}

		/* Load the bytes/status out of the ring entry */
		for (byte_num = 0; byte_num < 4 && len > 0; byte_num++) {
			sc = &(entry->ring_sc[byte_num]);

			/* Check for change in modem state or overrun */
			if ((*sc & IOC4_RXSB_MODEM_VALID)
						&& (port->ip_notify & N_DDCD)) {
				/* Notify upper layer if DCD dropped */

				if ((port->ip_flags & DCD_ON)
						&& !(*sc & IOC4_RXSB_DCD)) {

					/* If we have already copied some data,
					 * return it.  We'll pick up the carrier
					 * drop on the next pass.  That way we
					 * don't throw away the data that has
					 * already been copied back to
					 * the caller's buffer.
					 */
					if (total > 0) {
						len = 0;
						break;
					}
					port->ip_flags &= ~DCD_ON;

					/* Turn off this notification so the
					 * carrier drop protocol won't see it
					 * again when it does a read.
					 */
					*sc &= ~IOC4_RXSB_MODEM_VALID;

					/* To keep things consistent, we need
					 * to update the consumer pointer so
					 * the next reader won't come in and
					 * try to read the same ring entries
					 * again. This must be done here before
					 * the dcd change.
					 */

					if ((entry->ring_allsc & RING_ANY_VALID)
									== 0) {
						cons_ptr += (int)sizeof
							(struct ring_entry);
						cons_ptr &= PROD_CONS_MASK;
					}
					writel(cons_ptr,
						&port->ip_serial_regs->srcir);
					port->ip_rx_cons = cons_ptr;

					/* Notify upper layer of carrier drop */
					if ((port->ip_notify & N_DDCD)
						   && port->ip_port) {
						the_port->icount.dcd = 0;
						wake_up_interruptible
						    (&the_port->info->
							delta_msr_wait);
					}

					/* If we had any data to return, we
					 * would have returned it above.
					 */
					return 0;
				}
			}
			if (*sc & IOC4_RXSB_MODEM_VALID) {
				/* Notify that an input overrun occurred */
				if ((*sc & IOC4_RXSB_OVERRUN)
				    && (port->ip_notify & N_OVERRUN_ERROR)) {
					ioc4_cb_post_ncs(the_port, NCS_OVERRUN);
				}
				/* Don't look at this byte again */
				*sc &= ~IOC4_RXSB_MODEM_VALID;
			}

			/* Check for valid data or RX errors */
			if ((*sc & IOC4_RXSB_DATA_VALID) &&
					((*sc & (IOC4_RXSB_PAR_ERR
							| IOC4_RXSB_FRAME_ERR
							| IOC4_RXSB_BREAK))
					&& (port->ip_notify & (N_PARITY_ERROR
							| N_FRAMING_ERROR
							| N_BREAK)))) {
				/* There is an error condition on the next byte.
				 * If we have already transferred some bytes,
				 * we'll stop here. Otherwise if this is the
				 * first byte to be read, we'll just transfer
				 * it alone after notifying the
				 * upper layer of its status.
				 */
				if (total > 0) {
					len = 0;
					break;
				} else {
					if ((*sc & IOC4_RXSB_PAR_ERR) &&
					   (port->ip_notify & N_PARITY_ERROR)) {
						ioc4_cb_post_ncs(the_port,
								NCS_PARITY);
					}
					if ((*sc & IOC4_RXSB_FRAME_ERR) &&
					   (port->ip_notify & N_FRAMING_ERROR)){
						ioc4_cb_post_ncs(the_port,
								NCS_FRAMING);
					}
					if ((*sc & IOC4_RXSB_BREAK)
					    && (port->ip_notify & N_BREAK)) {
							ioc4_cb_post_ncs
								    (the_port,
								     NCS_BREAK);
					}
					len = 1;
				}
			}
			if (*sc & IOC4_RXSB_DATA_VALID) {
				*sc &= ~IOC4_RXSB_DATA_VALID;
				*buf = entry->ring_data[byte_num];
				buf++;
				len--;
				total++;
			}
		}

		/* If we used up this entry entirely, go on to the next one,
		 * otherwise we must have run out of buffer space, so
		 * leave the consumer pointer here for the next read in case
		 * there are still unread bytes in this entry.
		 */
		if ((entry->ring_allsc & RING_ANY_VALID) == 0) {
			cons_ptr += (int)sizeof(struct ring_entry);
			cons_ptr &= PROD_CONS_MASK;
		}
	}

	/* Update consumer pointer and re-arm rx timer interrupt */
	writel(cons_ptr, &port->ip_serial_regs->srcir);
	port->ip_rx_cons = cons_ptr;

	/* If we have now dipped below the rx high water mark and we have
	 * rx_high interrupt turned off, we can now turn it back on again.
	 */
	if ((port->ip_flags & INPUT_HIGH) && (((prod_ptr - cons_ptr)
			& PROD_CONS_MASK) < ((port->ip_sscr &
				IOC4_SSCR_RX_THRESHOLD)
					<< IOC4_PROD_CONS_PTR_OFF))) {
		port->ip_flags &= ~INPUT_HIGH;
		enable_intrs(port, hooks->intr_rx_high);
	}
	return total;
}

/**
 * receive_chars - upper level read. Called with ip_lock.
 * @the_port: port to read from
 */
static void receive_chars(struct uart_port *the_port)
{
	struct tty_struct *tty;
	unsigned char ch[IOC4_MAX_CHARS];
	int read_count, request_count = IOC4_MAX_CHARS;
	struct uart_icount *icount;
	struct uart_info *info = the_port->info;
	unsigned long pflags;

	/* Make sure all the pointers are "good" ones */
	if (!info)
		return;
	if (!info->tty)
		return;

	spin_lock_irqsave(&the_port->lock, pflags);
	tty = info->tty;

	request_count = tty_buffer_request_room(tty, IOC4_MAX_CHARS);

	if (request_count > 0) {
		icount = &the_port->icount;
		read_count = do_read(the_port, ch, request_count);
		if (read_count > 0) {
			tty_insert_flip_string(tty, ch, read_count);
			icount->rx += read_count;
		}
	}

	spin_unlock_irqrestore(&the_port->lock, pflags);

	tty_flip_buffer_push(tty);
}

/**
 * ic4_type - What type of console are we?
 * @port: Port to operate with (we ignore since we only have one port)
 *
 */
static const char *ic4_type(struct uart_port *the_port)
{
	if (the_port->mapbase == PROTO_RS232)
		return "SGI IOC4 Serial [rs232]";
	else
		return "SGI IOC4 Serial [rs422]";
}

/**
 * ic4_tx_empty - Is the transmitter empty?
 * @port: Port to operate on
 *
 */
static unsigned int ic4_tx_empty(struct uart_port *the_port)
{
	struct ioc4_port *port = get_ioc4_port(the_port, 0);
	unsigned int ret = 0;

	if (port_is_active(port, the_port)) {
		if (readl(&port->ip_serial_regs->shadow) & IOC4_SHADOW_TEMT)
			ret = TIOCSER_TEMT;
	}
	return ret;
}

/**
 * ic4_stop_tx - stop the transmitter
 * @port: Port to operate on
 *
 */
static void ic4_stop_tx(struct uart_port *the_port)
{
	struct ioc4_port *port = get_ioc4_port(the_port, 0);

	if (port_is_active(port, the_port))
		set_notification(port, N_OUTPUT_LOWAT, 0);
}

/**
 * null_void_function -
 * @port: Port to operate on
 *
 */
static void null_void_function(struct uart_port *the_port)
{
}

/**
 * ic4_shutdown - shut down the port - free irq and disable
 * @port: Port to shut down
 *
 */
static void ic4_shutdown(struct uart_port *the_port)
{
	unsigned long port_flags;
	struct ioc4_port *port;
	struct uart_info *info;

	port = get_ioc4_port(the_port, 0);
	if (!port)
		return;

	info = the_port->info;
	port->ip_port = NULL;

	wake_up_interruptible(&info->delta_msr_wait);

	if (info->tty)
		set_bit(TTY_IO_ERROR, &info->tty->flags);

	spin_lock_irqsave(&the_port->lock, port_flags);
	set_notification(port, N_ALL, 0);
	port->ip_flags = PORT_INACTIVE;
	spin_unlock_irqrestore(&the_port->lock, port_flags);
}

/**
 * ic4_set_mctrl - set control lines (dtr, rts, etc)
 * @port: Port to operate on
 * @mctrl: Lines to set/unset
 *
 */
static void ic4_set_mctrl(struct uart_port *the_port, unsigned int mctrl)
{
	unsigned char mcr = 0;
	struct ioc4_port *port;

	port = get_ioc4_port(the_port, 0);
	if (!port_is_active(port, the_port))
		return;

	if (mctrl & TIOCM_RTS)
		mcr |= UART_MCR_RTS;
	if (mctrl & TIOCM_DTR)
		mcr |= UART_MCR_DTR;
	if (mctrl & TIOCM_OUT1)
		mcr |= UART_MCR_OUT1;
	if (mctrl & TIOCM_OUT2)
		mcr |= UART_MCR_OUT2;
	if (mctrl & TIOCM_LOOP)
		mcr |= UART_MCR_LOOP;

	set_mcr(the_port, mcr, IOC4_SHADOW_DTR);
}

/**
 * ic4_get_mctrl - get control line info
 * @port: port to operate on
 *
 */
static unsigned int ic4_get_mctrl(struct uart_port *the_port)
{
	struct ioc4_port *port = get_ioc4_port(the_port, 0);
	uint32_t shadow;
	unsigned int ret = 0;

	if (!port_is_active(port, the_port))
		return 0;

	shadow = readl(&port->ip_serial_regs->shadow);
	if (shadow & IOC4_SHADOW_DCD)
		ret |= TIOCM_CAR;
	if (shadow & IOC4_SHADOW_DR)
		ret |= TIOCM_DSR;
	if (shadow & IOC4_SHADOW_CTS)
		ret |= TIOCM_CTS;
	return ret;
}

/**
 * ic4_start_tx - Start transmitter, flush any output
 * @port: Port to operate on
 *
 */
static void ic4_start_tx(struct uart_port *the_port)
{
	struct ioc4_port *port = get_ioc4_port(the_port, 0);

	if (port_is_active(port, the_port)) {
		set_notification(port, N_OUTPUT_LOWAT, 1);
		enable_intrs(port, port->ip_hooks->intr_tx_mt);
	}
}

/**
 * ic4_break_ctl - handle breaks
 * @port: Port to operate on
 * @break_state: Break state
 *
 */
static void ic4_break_ctl(struct uart_port *the_port, int break_state)
{
}

/**
 * ic4_startup - Start up the serial port
 * @port: Port to operate on
 *
 */
static int ic4_startup(struct uart_port *the_port)
{
	int retval;
	struct ioc4_port *port;
	struct ioc4_control *control;
	struct uart_info *info;
	unsigned long port_flags;

	if (!the_port)
		return -ENODEV;
	port = get_ioc4_port(the_port, 1);
	if (!port)
		return -ENODEV;
	info = the_port->info;

	control = port->ip_control;
	if (!control) {
		port->ip_port = NULL;
		return -ENODEV;
	}

	/* Start up the serial port */
	spin_lock_irqsave(&the_port->lock, port_flags);
	retval = ic4_startup_local(the_port);
	spin_unlock_irqrestore(&the_port->lock, port_flags);
	return retval;
}

/**
 * ic4_set_termios - set termios stuff
 * @port: port to operate on
 * @termios: New settings
 * @termios: Old
 *
 */
static void
ic4_set_termios(struct uart_port *the_port,
		struct termios *termios, struct termios *old_termios)
{
	unsigned long port_flags;

	spin_lock_irqsave(&the_port->lock, port_flags);
	ioc4_change_speed(the_port, termios, old_termios);
	spin_unlock_irqrestore(&the_port->lock, port_flags);
}

/**
 * ic4_request_port - allocate resources for port - no op....
 * @port: port to operate on
 *
 */
static int ic4_request_port(struct uart_port *port)
{
	return 0;
}

/* Associate the uart functions above - given to serial core */

static struct uart_ops ioc4_ops = {
	.tx_empty	= ic4_tx_empty,
	.set_mctrl	= ic4_set_mctrl,
	.get_mctrl	= ic4_get_mctrl,
	.stop_tx	= ic4_stop_tx,
	.start_tx	= ic4_start_tx,
	.stop_rx	= null_void_function,
	.enable_ms	= null_void_function,
	.break_ctl	= ic4_break_ctl,
	.startup	= ic4_startup,
	.shutdown	= ic4_shutdown,
	.set_termios	= ic4_set_termios,
	.type		= ic4_type,
	.release_port	= null_void_function,
	.request_port	= ic4_request_port,
};

/*
 * Boot-time initialization code
 */

static struct uart_driver ioc4_uart_rs232 = {
	.owner		= THIS_MODULE,
	.driver_name	= "ioc4_serial_rs232",
	.dev_name	= DEVICE_NAME_RS232,
	.major		= DEVICE_MAJOR,
	.minor		= DEVICE_MINOR_RS232,
	.nr		= IOC4_NUM_CARDS * IOC4_NUM_SERIAL_PORTS,
};

static struct uart_driver ioc4_uart_rs422 = {
	.owner		= THIS_MODULE,
	.driver_name	= "ioc4_serial_rs422",
	.dev_name	= DEVICE_NAME_RS422,
	.major		= DEVICE_MAJOR,
	.minor		= DEVICE_MINOR_RS422,
	.nr		= IOC4_NUM_CARDS * IOC4_NUM_SERIAL_PORTS,
};


/**
 * ioc4_serial_remove_one - detach function
 *
 * @idd: IOC4 master module data for this IOC4
 */

static int ioc4_serial_remove_one(struct ioc4_driver_data *idd)
{
	int port_num, port_type;
	struct ioc4_control *control;
	struct uart_port *the_port;
	struct ioc4_port *port;
	struct ioc4_soft *soft;

	/* If serial driver did not attach, don't try to detach */
	control = idd->idd_serial_data;
	if (!control)
		return 0;

	for (port_num = 0; port_num < IOC4_NUM_SERIAL_PORTS; port_num++) {
		for (port_type = UART_PORT_MIN;
					port_type < UART_PORT_COUNT;
					port_type++) {
			the_port = &control->ic_port[port_num].icp_uart_port
							[port_type];
			if (the_port) {
				switch (port_type) {
				case UART_PORT_RS422:
					uart_remove_one_port(&ioc4_uart_rs422,
							the_port);
					break;
				default:
				case UART_PORT_RS232:
					uart_remove_one_port(&ioc4_uart_rs232,
							the_port);
					break;
				}
			}
		}
		port = control->ic_port[port_num].icp_port;
		/* we allocate in pairs */
		if (!(port_num & 1) && port) {
			pci_free_consistent(port->ip_pdev,
					TOTAL_RING_BUF_SIZE,
					port->ip_cpu_ringbuf,
					port->ip_dma_ringbuf);
			kfree(port);
		}
	}
	soft = control->ic_soft;
	if (soft) {
		free_irq(control->ic_irq, soft);
		if (soft->is_ioc4_serial_addr) {
			iounmap(soft->is_ioc4_serial_addr);
			release_region((unsigned long)
			     soft->is_ioc4_serial_addr,
				sizeof(struct ioc4_serial));
		}
		kfree(soft);
	}
	kfree(control);
	idd->idd_serial_data = NULL;

	return 0;
}


/**
 * ioc4_serial_core_attach_rs232 - register with serial core
 *		This is done during pci probing
 * @pdev: handle for this card
 */
static inline int
ioc4_serial_core_attach(struct pci_dev *pdev, int port_type)
{
	struct ioc4_port *port;
	struct uart_port *the_port;
	struct ioc4_driver_data *idd = pci_get_drvdata(pdev);
	struct ioc4_control *control = idd->idd_serial_data;
	int port_num;
	int port_type_idx;
	struct uart_driver *u_driver;


	DPRINT_CONFIG(("%s: attach pdev 0x%p - control 0x%p\n",
			__FUNCTION__, pdev, (void *)control));

	if (!control)
		return -ENODEV;

	port_type_idx = (port_type == PROTO_RS232) ? UART_PORT_RS232
						: UART_PORT_RS422;

	u_driver = (port_type == PROTO_RS232)	? &ioc4_uart_rs232
						: &ioc4_uart_rs422;

	/* once around for each port on this card */
	for (port_num = 0; port_num < IOC4_NUM_SERIAL_PORTS; port_num++) {
		the_port = &control->ic_port[port_num].icp_uart_port
							[port_type_idx];
		port = control->ic_port[port_num].icp_port;
		port->ip_all_ports[port_type_idx] = the_port;

		DPRINT_CONFIG(("%s: attach the_port 0x%p / port 0x%p : type %s\n",
				__FUNCTION__, (void *)the_port,
				(void *)port,
				port_type == PROTO_RS232 ? "rs232" : "rs422"));

		/* membase, iobase and mapbase just need to be non-0 */
		the_port->membase = (unsigned char __iomem *)1;
		the_port->iobase = (pdev->bus->number << 16) |  port_num;
		the_port->line = (Num_of_ioc4_cards << 2) | port_num;
		the_port->mapbase = port_type;
		the_port->type = PORT_16550A;
		the_port->fifosize = IOC4_FIFO_CHARS;
		the_port->ops = &ioc4_ops;
		the_port->irq = control->ic_irq;
		the_port->dev = &pdev->dev;
		spin_lock_init(&the_port->lock);
		if (uart_add_one_port(u_driver, the_port) < 0) {
			printk(KERN_WARNING
		           "%s: unable to add port %d bus %d\n",
			       __FUNCTION__, the_port->line, pdev->bus->number);
		} else {
			DPRINT_CONFIG(
			    ("IOC4 serial port %d irq = %d, bus %d\n",
			       the_port->line, the_port->irq, pdev->bus->number));
		}
	}
	return 0;
}

/**
 * ioc4_serial_attach_one - register attach function
 *		called per card found from IOC4 master module.
 * @idd: Master module data for this IOC4
 */
int
ioc4_serial_attach_one(struct ioc4_driver_data *idd)
{
	unsigned long tmp_addr1;
	struct ioc4_serial __iomem *serial;
	struct ioc4_soft *soft;
	struct ioc4_control *control;
	int ret = 0;


	DPRINT_CONFIG(("%s (0x%p, 0x%p)\n", __FUNCTION__, idd->idd_pdev,
							idd->idd_pci_id));

	/* PCI-RT does not bring out serial connections.
	 * Do not attach to this particular IOC4.
	 */
	if (idd->idd_variant == IOC4_VARIANT_PCI_RT)
		return 0;

	/* request serial registers */
	tmp_addr1 = idd->idd_bar0 + IOC4_SERIAL_OFFSET;

	if (!request_region(tmp_addr1, sizeof(struct ioc4_serial),
					"sioc4_uart")) {
		printk(KERN_WARNING
			"ioc4 (%p): unable to get request region for "
				"uart space\n", (void *)idd->idd_pdev);
		ret = -ENODEV;
		goto out1;
	}
	serial = ioremap(tmp_addr1, sizeof(struct ioc4_serial));
	if (!serial) {
		printk(KERN_WARNING
			 "ioc4 (%p) : unable to remap ioc4 serial register\n",
				(void *)idd->idd_pdev);
		ret = -ENODEV;
		goto out2;
	}
	DPRINT_CONFIG(("%s : mem 0x%p, serial 0x%p\n",
				__FUNCTION__, (void *)idd->idd_misc_regs,
				(void *)serial));

	/* Get memory for the new card */
	control = kmalloc(sizeof(struct ioc4_control), GFP_KERNEL);

	if (!control) {
		printk(KERN_WARNING "ioc4_attach_one"
		       ": unable to get memory for the IOC4\n");
		ret = -ENOMEM;
		goto out2;
	}
	memset(control, 0, sizeof(struct ioc4_control));
	idd->idd_serial_data = control;

	/* Allocate the soft structure */
	soft = kmalloc(sizeof(struct ioc4_soft), GFP_KERNEL);
	if (!soft) {
		printk(KERN_WARNING
		       "ioc4 (%p): unable to get memory for the soft struct\n",
		       (void *)idd->idd_pdev);
		ret = -ENOMEM;
		goto out3;
	}
	memset(soft, 0, sizeof(struct ioc4_soft));

	spin_lock_init(&soft->is_ir_lock);
	soft->is_ioc4_misc_addr = idd->idd_misc_regs;
	soft->is_ioc4_serial_addr = serial;

	/* Init the IOC4 */
	writel(0xf << IOC4_SIO_CR_CMD_PULSE_SHIFT,
	       &idd->idd_misc_regs->sio_cr.raw);

	/* Enable serial port mode select generic PIO pins as outputs */
	writel(IOC4_GPCR_UART0_MODESEL | IOC4_GPCR_UART1_MODESEL
		| IOC4_GPCR_UART2_MODESEL | IOC4_GPCR_UART3_MODESEL,
		&idd->idd_misc_regs->gpcr_s.raw);

	/* Clear and disable all serial interrupts */
	write_ireg(soft, ~0, IOC4_W_IEC, IOC4_SIO_INTR_TYPE);
	writel(~0, &idd->idd_misc_regs->sio_ir.raw);
	write_ireg(soft, IOC4_OTHER_IR_SER_MEMERR, IOC4_W_IEC,
		   IOC4_OTHER_INTR_TYPE);
	writel(IOC4_OTHER_IR_SER_MEMERR, &idd->idd_misc_regs->other_ir.raw);
	control->ic_soft = soft;

	/* Hook up interrupt handler */
	if (!request_irq(idd->idd_pdev->irq, ioc4_intr, IRQF_SHARED,
				"sgi-ioc4serial", soft)) {
		control->ic_irq = idd->idd_pdev->irq;
	} else {
		printk(KERN_WARNING
		    "%s : request_irq fails for IRQ 0x%x\n ",
			__FUNCTION__, idd->idd_pdev->irq);
	}
	ret = ioc4_attach_local(idd);
	if (ret)
		goto out4;

	/* register port with the serial core - 1 rs232, 1 rs422 */

	if ((ret = ioc4_serial_core_attach(idd->idd_pdev, PROTO_RS232)))
		goto out4;

	if ((ret = ioc4_serial_core_attach(idd->idd_pdev, PROTO_RS422)))
		goto out5;

	Num_of_ioc4_cards++;

	return ret;

	/* error exits that give back resources */
out5:
	ioc4_serial_remove_one(idd);
out4:
	kfree(soft);
out3:
	kfree(control);
out2:
	if (serial)
		iounmap(serial);
	release_region(tmp_addr1, sizeof(struct ioc4_serial));
out1:

	return ret;
}


static struct ioc4_submodule ioc4_serial_submodule = {
	.is_name = "IOC4_serial",
	.is_owner = THIS_MODULE,
	.is_probe = ioc4_serial_attach_one,
	.is_remove = ioc4_serial_remove_one,
};

/**
 * ioc4_serial_init - module init
 */
int ioc4_serial_init(void)
{
	int ret;

	/* register with serial core */
	if ((ret = uart_register_driver(&ioc4_uart_rs232)) < 0) {
		printk(KERN_WARNING
			"%s: Couldn't register rs232 IOC4 serial driver\n",
			__FUNCTION__);
		return ret;
	}
	if ((ret = uart_register_driver(&ioc4_uart_rs422)) < 0) {
		printk(KERN_WARNING
			"%s: Couldn't register rs422 IOC4 serial driver\n",
			__FUNCTION__);
		return ret;
	}

	/* register with IOC4 main module */
	return ioc4_register_submodule(&ioc4_serial_submodule);
}

static void __devexit ioc4_serial_exit(void)
{
	ioc4_unregister_submodule(&ioc4_serial_submodule);
	uart_unregister_driver(&ioc4_uart_rs232);
	uart_unregister_driver(&ioc4_uart_rs422);
}

module_init(ioc4_serial_init);
module_exit(ioc4_serial_exit);

MODULE_AUTHOR("Pat Gefre - Silicon Graphics Inc. (SGI) <pfg@sgi.com>");
MODULE_DESCRIPTION("Serial PCI driver module for SGI IOC4 Base-IO Card");
MODULE_LICENSE("GPL");
OpenPOWER on IntegriCloud