aboutsummaryrefslogtreecommitdiff
path: root/tools/kwboot.c
blob: 4dfb1038b4ffd078b8c6d5a569f6a462a7beae78 (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
/*
 * Boot a Marvell SoC, with Xmodem over UART0.
 *  supports Kirkwood, Dove, Armada 370, Armada XP, Armada 375, Armada 38x and
 *           Armada 39x
 *
 * (c) 2012 Daniel Stodden <daniel.stodden@gmail.com>
 * (c) 2021 Pali Rohár <pali@kernel.org>
 * (c) 2021 Marek Behún <marek.behun@nic.cz>
 *
 * References: marvell.com, "88F6180, 88F6190, 88F6192, and 88F6281
 *   Integrated Controller: Functional Specifications" December 2,
 *   2008. Chapter 24.2 "BootROM Firmware".
 */

#include "kwbimage.h"
#include "mkimage.h"
#include "version.h"

#include <stdlib.h>
#include <stdio.h>
#include <string.h>
#include <stdarg.h>
#include <image.h>
#include <libgen.h>
#include <fcntl.h>
#include <errno.h>
#include <unistd.h>
#include <stdint.h>
#include <time.h>
#include <sys/stat.h>

#ifdef __linux__
#include "termios_linux.h"
#else
#include <termios.h>
#endif

/*
 * Marvell BootROM UART Sensing
 */

static unsigned char kwboot_msg_boot[] = {
	0xBB, 0x11, 0x22, 0x33, 0x44, 0x55, 0x66, 0x77
};

static unsigned char kwboot_msg_debug[] = {
	0xDD, 0x11, 0x22, 0x33, 0x44, 0x55, 0x66, 0x77
};

/* Defines known to work on Kirkwood */
#define KWBOOT_MSG_RSP_TIMEO	50 /* ms */

/* Defines known to work on Armada XP */
#define KWBOOT_MSG_RSP_TIMEO_AXP	1000 /* ms */

/*
 * Xmodem Transfers
 */

#define SOH	1	/* sender start of block header */
#define EOT	4	/* sender end of block transfer */
#define ACK	6	/* target block ack */
#define NAK	21	/* target block negative ack */

#define KWBOOT_XM_BLKSZ	128 /* xmodem block size */

struct kwboot_block {
	uint8_t soh;
	uint8_t pnum;
	uint8_t _pnum;
	uint8_t data[KWBOOT_XM_BLKSZ];
	uint8_t csum;
} __packed;

#define KWBOOT_BLK_RSP_TIMEO 2000 /* ms */
#define KWBOOT_HDR_RSP_TIMEO 10000 /* ms */

/* ARM code to change baudrate */
static unsigned char kwboot_baud_code[] = {
				/* ; #define UART_BASE 0xd0012000             */
				/* ; #define DLL       0x00                   */
				/* ; #define DLH       0x04                   */
				/* ; #define LCR       0x0c                   */
				/* ; #define   DLAB    0x80                   */
				/* ; #define LSR       0x14                   */
				/* ; #define   TEMT    0x40                   */
				/* ; #define DIV_ROUND(a, b) ((a + b/2) / b)  */
				/* ;                                          */
				/* ; u32 set_baudrate(u32 old_b, u32 new_b) { */
				/* ;   while                                  */
				/* ;      (!(readl(UART_BASE + LSR) & TEMT)); */
				/* ;   u32 lcr = readl(UART_BASE + LCR);      */
				/* ;   writel(UART_BASE + LCR, lcr | DLAB);   */
				/* ;   u8 old_dll = readl(UART_BASE + DLL);   */
				/* ;   u8 old_dlh = readl(UART_BASE + DLH);   */
				/* ;   u16 old_dl = old_dll | (old_dlh << 8); */
				/* ;   u32 clk = old_b * old_dl;              */
				/* ;   u16 new_dl = DIV_ROUND(clk, new_b);    */
				/* ;   u8 new_dll = new_dl & 0xff;            */
				/* ;   u8 new_dlh = (new_dl >> 8) & 0xff;     */
				/* ;   writel(UART_BASE + DLL, new_dll);      */
				/* ;   writel(UART_BASE + DLH, new_dlh);      */
				/* ;   writel(UART_BASE + LCR, lcr & ~DLAB);  */
				/* ;   msleep(5);                             */
				/* ;   return 0;                              */
				/* ; }                                        */

				/*  ; r0 = UART_BASE                          */
	0x0d, 0x02, 0xa0, 0xe3, /* mov   r0, #0xd0000000                      */
	0x12, 0x0a, 0x80, 0xe3, /* orr   r0, r0, #0x12000                     */

				/*  ; Wait until Transmitter FIFO is Empty    */
				/* .Lloop_txempty:                            */
				/*  ; r1 = UART_BASE[LSR] & TEMT              */
	0x14, 0x10, 0x90, 0xe5, /* ldr   r1, [r0, #0x14]                      */
	0x40, 0x00, 0x11, 0xe3, /* tst   r1, #0x40                            */
	0xfc, 0xff, 0xff, 0x0a, /* beq   .Lloop_txempty                       */

				/*  ; Set Divisor Latch Access Bit            */
				/*  ; UART_BASE[LCR] |= DLAB                  */
	0x0c, 0x10, 0x90, 0xe5, /* ldr   r1, [r0, #0x0c]                      */
	0x80, 0x10, 0x81, 0xe3, /* orr   r1, r1, #0x80                        */
	0x0c, 0x10, 0x80, 0xe5, /* str   r1, [r0, #0x0c]                      */

				/*  ; Read current Divisor Latch              */
				/*  ; r1 = UART_BASE[DLH]<<8 | UART_BASE[DLL] */
	0x00, 0x10, 0x90, 0xe5, /* ldr   r1, [r0, #0x00]                      */
	0xff, 0x10, 0x01, 0xe2, /* and   r1, r1, #0xff                        */
	0x01, 0x20, 0xa0, 0xe1, /* mov   r2, r1                               */
	0x04, 0x10, 0x90, 0xe5, /* ldr   r1, [r0, #0x04]                      */
	0xff, 0x10, 0x01, 0xe2, /* and   r1, r1, #0xff                        */
	0x41, 0x14, 0xa0, 0xe1, /* asr   r1, r1, #8                           */
	0x02, 0x10, 0x81, 0xe1, /* orr   r1, r1, r2                           */

				/*  ; Read old baudrate value                 */
				/*  ; r2 = old_baudrate                       */
	0x74, 0x20, 0x9f, 0xe5, /* ldr   r2, old_baudrate                     */

				/*  ; Calculate base clock                    */
				/*  ; r1 = r2 * r1                            */
	0x92, 0x01, 0x01, 0xe0, /* mul   r1, r2, r1                           */

				/*  ; Read new baudrate value                 */
				/*  ; r2 = new_baudrate                       */
	0x70, 0x20, 0x9f, 0xe5, /* ldr   r2, new_baudrate                     */

				/*  ; Calculate new Divisor Latch             */
				/*  ; r1 = DIV_ROUND(r1, r2) =                */
				/*  ;    = (r1 + r2/2) / r2                   */
	0xa2, 0x10, 0x81, 0xe0, /* add   r1, r1, r2, lsr #1                   */
	0x02, 0x40, 0xa0, 0xe1, /* mov   r4, r2                               */
	0xa1, 0x00, 0x54, 0xe1, /* cmp   r4, r1, lsr #1                       */
				/* .Lloop_div1:                               */
	0x84, 0x40, 0xa0, 0x91, /* movls r4, r4, lsl #1                       */
	0xa1, 0x00, 0x54, 0xe1, /* cmp   r4, r1, lsr #1                       */
	0xfc, 0xff, 0xff, 0x9a, /* bls   .Lloop_div1                          */
	0x00, 0x30, 0xa0, 0xe3, /* mov   r3, #0                               */
				/* .Lloop_div2:                               */
	0x04, 0x00, 0x51, 0xe1, /* cmp   r1, r4                               */
	0x04, 0x10, 0x41, 0x20, /* subhs r1, r1, r4                           */
	0x03, 0x30, 0xa3, 0xe0, /* adc   r3, r3, r3                           */
	0xa4, 0x40, 0xa0, 0xe1, /* mov   r4, r4, lsr #1                       */
	0x02, 0x00, 0x54, 0xe1, /* cmp   r4, r2                               */
	0xf9, 0xff, 0xff, 0x2a, /* bhs   .Lloop_div2                          */
	0x03, 0x10, 0xa0, 0xe1, /* mov   r1, r3                               */

				/*  ; Set new Divisor Latch Low               */
				/*  ; UART_BASE[DLL] = r1 & 0xff              */
	0x01, 0x20, 0xa0, 0xe1, /* mov   r2, r1                               */
	0xff, 0x20, 0x02, 0xe2, /* and   r2, r2, #0xff                        */
	0x00, 0x20, 0x80, 0xe5, /* str   r2, [r0, #0x00]                      */

				/*  ; Set new Divisor Latch High              */
				/*  ; UART_BASE[DLH] = r1>>8 & 0xff           */
	0x41, 0x24, 0xa0, 0xe1, /* asr   r2, r1, #8                           */
	0xff, 0x20, 0x02, 0xe2, /* and   r2, r2, #0xff                        */
	0x04, 0x20, 0x80, 0xe5, /* str   r2, [r0, #0x04]                      */

				/*  ; Clear Divisor Latch Access Bit          */
				/*  ; UART_BASE[LCR] &= ~DLAB                 */
	0x0c, 0x10, 0x90, 0xe5, /* ldr   r1, [r0, #0x0c]                      */
	0x80, 0x10, 0xc1, 0xe3, /* bic   r1, r1, #0x80                        */
	0x0c, 0x10, 0x80, 0xe5, /* str   r1, [r0, #0x0c]                      */

				/*  ; Loop 0x2dc000 (2998272) cycles          */
				/*  ; which is about 5ms on 1200 MHz CPU      */
				/*  ; r1 = 0x2dc000                           */
	0xb7, 0x19, 0xa0, 0xe3, /* mov   r1, #0x2dc000                        */
				/* .Lloop_sleep:                              */
	0x01, 0x10, 0x41, 0xe2, /* sub   r1, r1, #1                           */
	0x00, 0x00, 0x51, 0xe3, /* cmp   r1, #0                               */
	0xfc, 0xff, 0xff, 0x1a, /* bne   .Lloop_sleep                         */

				/*  ; Jump to the end of execution            */
	0x01, 0x00, 0x00, 0xea, /* b     end                                  */

				/*  ; Placeholder for old baudrate value      */
				/* old_baudrate:                              */
	0x00, 0x00, 0x00, 0x00, /* .word 0                                    */

				/*  ; Placeholder for new baudrate value      */
				/* new_baudrate:                              */
	0x00, 0x00, 0x00, 0x00, /* .word 0                                    */

				/* end:                                       */
};

/* ARM code from binary header executed by BootROM before changing baudrate */
static unsigned char kwboot_baud_code_binhdr_pre[] = {
				/* ; #define UART_BASE 0xd0012000             */
				/* ; #define THR       0x00                   */
				/* ; #define LSR       0x14                   */
				/* ; #define   THRE    0x20                   */
				/* ;                                          */
				/* ; void send_preamble(void) {               */
				/* ;   const u8 *str = "$baudratechange";     */
				/* ;   u8 c;                                  */
				/* ;   do {                                   */
				/* ;       while                              */
				/* ;       ((readl(UART_BASE + LSR) & THRE)); */
				/* ;       c = *str++;                        */
				/* ;       writel(UART_BASE + THR, c);        */
				/* ;   } while (c);                           */
				/* ; }                                        */

				/*  ; Preserve registers for BootROM          */
	0xfe, 0x5f, 0x2d, 0xe9, /* push  { r1 - r12, lr }                     */

				/*  ; r0 = UART_BASE                          */
	0x0d, 0x02, 0xa0, 0xe3, /* mov   r0, #0xd0000000                      */
	0x12, 0x0a, 0x80, 0xe3, /* orr   r0, r0, #0x12000                     */

				/*  ; r2 = address of preamble string         */
	0x00, 0x20, 0x8f, 0xe2, /* adr   r2, .Lstr_preamble                   */

				/*  ; Skip preamble data section              */
	0x03, 0x00, 0x00, 0xea, /* b     .Lloop_preamble                      */

				/*  ; Preamble string                         */
				/* .Lstr_preamble:                            */
	0x24, 0x62, 0x61, 0x75, /* .asciz "$baudratechange"                   */
	0x64, 0x72, 0x61, 0x74,
	0x65, 0x63, 0x68, 0x61,
	0x6e, 0x67, 0x65, 0x00,

				/*  ; Send preamble string over UART          */
				/* .Lloop_preamble:                           */
				/*                                            */
				/*  ; Wait until Transmitter Holding is Empty */
				/* .Lloop_thre:                               */
				/*  ; r1 = UART_BASE[LSR] & THRE              */
	0x14, 0x10, 0x90, 0xe5, /* ldr   r1, [r0, #0x14]                      */
	0x20, 0x00, 0x11, 0xe3, /* tst   r1, #0x20                            */
	0xfc, 0xff, 0xff, 0x0a, /* beq   .Lloop_thre                          */

				/*  ; Put character into Transmitter FIFO     */
				/*  ; r1 = *r2++                              */
	0x01, 0x10, 0xd2, 0xe4, /* ldrb  r1, [r2], #1                         */
				/*  ; UART_BASE[THR] = r1                     */
	0x00, 0x10, 0x80, 0xe5, /* str   r1, [r0, #0x0]                       */

				/*  ; Loop until end of preamble string       */
	0x00, 0x00, 0x51, 0xe3, /* cmp   r1, #0                               */
	0xf8, 0xff, 0xff, 0x1a, /* bne   .Lloop_preamble                      */
};

/* ARM code for returning from binary header back to BootROM */
static unsigned char kwboot_baud_code_binhdr_post[] = {
				/*  ; Return 0 - no error                     */
	0x00, 0x00, 0xa0, 0xe3, /* mov   r0, #0                               */
	0xfe, 0x9f, 0xbd, 0xe8, /* pop   { r1 - r12, pc }                     */
};

/* ARM code for jumping to the original image exec_addr */
static unsigned char kwboot_baud_code_data_jump[] = {
	0x04, 0xf0, 0x1f, 0xe5, /* ldr   pc, exec_addr                        */
				/*  ; Placeholder for exec_addr               */
				/* exec_addr:                                 */
	0x00, 0x00, 0x00, 0x00, /* .word 0                                    */
};

static const char kwb_baud_magic[16] = "$baudratechange";

static int kwboot_verbose;

static int msg_rsp_timeo = KWBOOT_MSG_RSP_TIMEO;
static int blk_rsp_timeo = KWBOOT_BLK_RSP_TIMEO;

static ssize_t
kwboot_write(int fd, const char *buf, size_t len)
{
	ssize_t tot = 0;

	while (tot < len) {
		ssize_t wr = write(fd, buf + tot, len - tot);

		if (wr < 0 && errno == EINTR)
			continue;
		else if (wr < 0)
			return wr;

		tot += wr;
	}

	return tot;
}

static void
kwboot_printv(const char *fmt, ...)
{
	va_list ap;

	if (kwboot_verbose) {
		va_start(ap, fmt);
		vprintf(fmt, ap);
		va_end(ap);
		fflush(stdout);
	}
}

static void
__spinner(void)
{
	const char seq[] = { '-', '\\', '|', '/' };
	const int div = 8;
	static int state, bs;

	if (state % div == 0) {
		fputc(bs, stdout);
		fputc(seq[state / div % sizeof(seq)], stdout);
		fflush(stdout);
	}

	bs = '\b';
	state++;
}

static void
kwboot_spinner(void)
{
	if (kwboot_verbose)
		__spinner();
}

static void
__progress(int pct, char c)
{
	const int width = 70;
	static const char *nl = "";
	static int pos;

	if (pos % width == 0)
		printf("%s%3d %% [", nl, pct);

	fputc(c, stdout);

	nl = "]\n";
	pos = (pos + 1) % width;

	if (pct == 100) {
		while (pos && pos++ < width)
			fputc(' ', stdout);
		fputs(nl, stdout);
		nl = "";
		pos = 0;
	}

	fflush(stdout);

}

static void
kwboot_progress(int _pct, char c)
{
	static int pct;

	if (_pct != -1)
		pct = _pct;

	if (kwboot_verbose)
		__progress(pct, c);

	if (pct == 100)
		pct = 0;
}

static int
kwboot_tty_recv(int fd, void *buf, size_t len, int timeo)
{
	int rc, nfds;
	fd_set rfds;
	struct timeval tv;
	ssize_t n;

	rc = -1;

	FD_ZERO(&rfds);
	FD_SET(fd, &rfds);

	tv.tv_sec = 0;
	tv.tv_usec = timeo * 1000;
	if (tv.tv_usec > 1000000) {
		tv.tv_sec += tv.tv_usec / 1000000;
		tv.tv_usec %= 1000000;
	}

	do {
		nfds = select(fd + 1, &rfds, NULL, NULL, &tv);
		if (nfds < 0 && errno == EINTR)
			continue;
		else if (nfds < 0)
			goto out;
		else if (!nfds) {
			errno = ETIMEDOUT;
			goto out;
		}

		n = read(fd, buf, len);
		if (n < 0 && errno == EINTR)
			continue;
		else if (n <= 0)
			goto out;

		buf = (char *)buf + n;
		len -= n;
	} while (len > 0);

	rc = 0;
out:
	return rc;
}

static int
kwboot_tty_send(int fd, const void *buf, size_t len, int nodrain)
{
	if (!buf)
		return 0;

	if (kwboot_write(fd, buf, len) < 0)
		return -1;

	if (nodrain)
		return 0;

	return tcdrain(fd);
}

static int
kwboot_tty_send_char(int fd, unsigned char c)
{
	return kwboot_tty_send(fd, &c, 1, 0);
}

static speed_t
kwboot_tty_baudrate_to_speed(int baudrate)
{
	switch (baudrate) {
#ifdef B4000000
	case 4000000:
		return B4000000;
#endif
#ifdef B3500000
	case 3500000:
		return B3500000;
#endif
#ifdef B3000000
	case 3000000:
		return B3000000;
#endif
#ifdef B2500000
	case 2500000:
		return B2500000;
#endif
#ifdef B2000000
	case 2000000:
		return B2000000;
#endif
#ifdef B1500000
	case 1500000:
		return B1500000;
#endif
#ifdef B1152000
	case 1152000:
		return B1152000;
#endif
#ifdef B1000000
	case 1000000:
		return B1000000;
#endif
#ifdef B921600
	case 921600:
		return B921600;
#endif
#ifdef B614400
	case 614400:
		return B614400;
#endif
#ifdef B576000
	case 576000:
		return B576000;
#endif
#ifdef B500000
	case 500000:
		return B500000;
#endif
#ifdef B460800
	case 460800:
		return B460800;
#endif
#ifdef B307200
	case 307200:
		return B307200;
#endif
#ifdef B230400
	case 230400:
		return B230400;
#endif
#ifdef B153600
	case 153600:
		return B153600;
#endif
#ifdef B115200
	case 115200:
		return B115200;
#endif
#ifdef B76800
	case 76800:
		return B76800;
#endif
#ifdef B57600
	case 57600:
		return B57600;
#endif
#ifdef B38400
	case 38400:
		return B38400;
#endif
#ifdef B19200
	case 19200:
		return B19200;
#endif
#ifdef B9600
	case 9600:
		return B9600;
#endif
#ifdef B4800
	case 4800:
		return B4800;
#endif
#ifdef B2400
	case 2400:
		return B2400;
#endif
#ifdef B1800
	case 1800:
		return B1800;
#endif
#ifdef B1200
	case 1200:
		return B1200;
#endif
#ifdef B600
	case 600:
		return B600;
#endif
#ifdef B300
	case 300:
		return B300;
#endif
#ifdef B200
	case 200:
		return B200;
#endif
#ifdef B150
	case 150:
		return B150;
#endif
#ifdef B134
	case 134:
		return B134;
#endif
#ifdef B110
	case 110:
		return B110;
#endif
#ifdef B75
	case 75:
		return B75;
#endif
#ifdef B50
	case 50:
		return B50;
#endif
	default:
#ifdef BOTHER
		return BOTHER;
#else
		return B0;
#endif
	}
}

static int
_is_within_tolerance(int value, int reference, int tolerance)
{
	return 100 * value >= reference * (100 - tolerance) &&
	       100 * value <= reference * (100 + tolerance);
}

static int
kwboot_tty_change_baudrate(int fd, int baudrate)
{
	struct termios tio;
	speed_t speed;
	int rc;

	rc = tcgetattr(fd, &tio);
	if (rc)
		return rc;

	speed = kwboot_tty_baudrate_to_speed(baudrate);
	if (speed == B0) {
		errno = EINVAL;
		return -1;
	}

#ifdef BOTHER
	if (speed == BOTHER)
		tio.c_ospeed = tio.c_ispeed = baudrate;
#endif

	rc = cfsetospeed(&tio, speed);
	if (rc)
		return rc;

	rc = cfsetispeed(&tio, speed);
	if (rc)
		return rc;

	rc = tcsetattr(fd, TCSANOW, &tio);
	if (rc)
		return rc;

	rc = tcgetattr(fd, &tio);
	if (rc)
		return rc;

	if (cfgetospeed(&tio) != speed || cfgetispeed(&tio) != speed)
		goto baud_fail;

#ifdef BOTHER
	/*
	 * Check whether set baudrate is within 3% tolerance.
	 * If BOTHER is defined, Linux always fills out c_ospeed / c_ispeed
	 * with real values.
	 */
	if (!_is_within_tolerance(tio.c_ospeed, baudrate, 3))
		goto baud_fail;

	if (!_is_within_tolerance(tio.c_ispeed, baudrate, 3))
		goto baud_fail;
#endif

	return 0;

baud_fail:
	fprintf(stderr, "Could not set baudrate to requested value\n");
	errno = EINVAL;
	return -1;
}

static int
kwboot_open_tty(const char *path, int baudrate)
{
	int rc, fd, flags;
	struct termios tio;

	rc = -1;

	fd = open(path, O_RDWR | O_NOCTTY | O_NDELAY);
	if (fd < 0)
		goto out;

	rc = tcgetattr(fd, &tio);
	if (rc)
		goto out;

	cfmakeraw(&tio);
	tio.c_cflag |= CREAD | CLOCAL;
	tio.c_cflag &= ~(CSTOPB | HUPCL | CRTSCTS);
	tio.c_cc[VMIN] = 1;
	tio.c_cc[VTIME] = 0;

	rc = tcsetattr(fd, TCSANOW, &tio);
	if (rc)
		goto out;

	flags = fcntl(fd, F_GETFL);
	if (flags < 0)
		goto out;

	rc = fcntl(fd, F_SETFL, flags & ~O_NDELAY);
	if (rc)
		goto out;

	rc = kwboot_tty_change_baudrate(fd, baudrate);
	if (rc)
		goto out;

	rc = fd;
out:
	if (rc < 0) {
		if (fd >= 0)
			close(fd);
	}

	return rc;
}

static int
kwboot_bootmsg(int tty, void *msg)
{
	struct kwboot_block block;
	int rc;
	char c;
	int count;

	if (msg == NULL)
		kwboot_printv("Please reboot the target into UART boot mode...");
	else
		kwboot_printv("Sending boot message. Please reboot the target...");

	do {
		rc = tcflush(tty, TCIOFLUSH);
		if (rc)
			break;

		for (count = 0; count < 128; count++) {
			rc = kwboot_tty_send(tty, msg, 8, 0);
			if (rc)
				break;
		}

		rc = kwboot_tty_recv(tty, &c, 1, msg_rsp_timeo);

		kwboot_spinner();

	} while (rc || c != NAK);

	kwboot_printv("\n");

	if (rc)
		return rc;

	/*
	 * At this stage we have sent more boot message patterns and BootROM
	 * (at least on Armada XP and 385) started interpreting sent bytes as
	 * part of xmodem packets. If BootROM is expecting SOH byte as start of
	 * a xmodem packet and it receives byte 0xff, then it throws it away and
	 * sends a NAK reply to host. If BootROM does not receive any byte for
	 * 2s when expecting some continuation of the xmodem packet, it throws
	 * away the partially received xmodem data and sends NAK reply to host.
	 *
	 * Therefore for starting xmodem transfer we have two options: Either
	 * wait 2s or send 132 0xff bytes (which is the size of xmodem packet)
	 * to ensure that BootROM throws away any partially received data.
	 */

	/* flush output queue with remaining boot message patterns */
	rc = tcflush(tty, TCOFLUSH);
	if (rc) {
		perror("Failed to flush output queue");
		return rc;
	}

	/* send one xmodem packet with 0xff bytes to force BootROM to re-sync */
	memset(&block, 0xff, sizeof(block));
	rc = kwboot_tty_send(tty, &block, sizeof(block), 0);
	if (rc) {
		perror("Failed to send sync sequence");
		return rc;
	}

	/*
	 * Sending 132 bytes via 115200B/8-N-1 takes 11.45 ms, reading 132 bytes
	 * takes 11.45 ms, so waiting for 30 ms should be enough.
	 */
	usleep(30 * 1000);

	/* flush remaining NAK replies from input queue */
	rc = tcflush(tty, TCIFLUSH);
	if (rc) {
		perror("Failed to flush input queue");
		return rc;
	}

	return 0;
}

static int
kwboot_debugmsg(int tty, void *msg)
{
	int rc;

	kwboot_printv("Sending debug message. Please reboot the target...");

	do {
		char buf[16];

		rc = tcflush(tty, TCIOFLUSH);
		if (rc)
			break;

		rc = kwboot_tty_send(tty, msg, 8, 0);
		if (rc)
			break;

		rc = kwboot_tty_recv(tty, buf, 16, msg_rsp_timeo);

		kwboot_spinner();

	} while (rc);

	kwboot_printv("\n");

	return rc;
}

static size_t
kwboot_xm_makeblock(struct kwboot_block *block, const void *data,
		    size_t size, int pnum)
{
	size_t i, n;

	block->soh = SOH;
	block->pnum = pnum;
	block->_pnum = ~block->pnum;

	n = size < KWBOOT_XM_BLKSZ ? size : KWBOOT_XM_BLKSZ;
	memcpy(&block->data[0], data, n);
	memset(&block->data[n], 0, KWBOOT_XM_BLKSZ - n);

	block->csum = 0;
	for (i = 0; i < n; i++)
		block->csum += block->data[i];

	return n;
}

static uint64_t
_now(void)
{
	struct timespec ts;

	if (clock_gettime(CLOCK_MONOTONIC, &ts)) {
		static int err_print;

		if (!err_print) {
			perror("clock_gettime() does not work");
			err_print = 1;
		}

		/* this will just make the timeout not work */
		return -1ULL;
	}

	return ts.tv_sec * 1000ULL + (ts.tv_nsec + 500000) / 1000000;
}

static int
_is_xm_reply(char c)
{
	return c == ACK || c == NAK;
}

static int
_xm_reply_to_error(int c)
{
	int rc = -1;

	switch (c) {
	case ACK:
		rc = 0;
		break;
	case NAK:
		errno = EBADMSG;
		break;
	default:
		errno = EPROTO;
		break;
	}

	return rc;
}

static int
kwboot_baud_magic_handle(int fd, char c, int baudrate)
{
	static size_t rcv_len;

	if (rcv_len < sizeof(kwb_baud_magic)) {
		/* try to recognize whole magic word */
		if (c == kwb_baud_magic[rcv_len]) {
			rcv_len++;
		} else {
			printf("%.*s%c", (int)rcv_len, kwb_baud_magic, c);
			fflush(stdout);
			rcv_len = 0;
		}
	}

	if (rcv_len == sizeof(kwb_baud_magic)) {
		/* magic word received */
		kwboot_printv("\nChanging baudrate to %d Bd\n", baudrate);

		return kwboot_tty_change_baudrate(fd, baudrate) ? : 1;
	} else {
		return 0;
	}
}

static int
kwboot_xm_recv_reply(int fd, char *c, int stop_on_non_xm,
		     int ignore_nak_reply,
		     int allow_non_xm, int *non_xm_print,
		     int baudrate, int *baud_changed)
{
	int timeout = allow_non_xm ? KWBOOT_HDR_RSP_TIMEO : blk_rsp_timeo;
	uint64_t recv_until = _now() + timeout;
	int rc;

	while (1) {
		rc = kwboot_tty_recv(fd, c, 1, timeout);
		if (rc) {
			if (errno != ETIMEDOUT)
				return rc;
			else if (allow_non_xm && *non_xm_print)
				return -1;
			else
				*c = NAK;
		}

		/* If received xmodem reply, end. */
		if (_is_xm_reply(*c)) {
			if (*c == NAK && ignore_nak_reply) {
				timeout = recv_until - _now();
				if (timeout >= 0)
					continue;
			}
			break;
		}

		/*
		 * If receiving/printing non-xmodem text output is allowed and
		 * such a byte was received, we want to increase receiving time
		 * and either:
		 * - print the byte, if it is not part of baudrate change magic
		 *   sequence while baudrate change was requested (-B option)
		 * - change baudrate
		 * Otherwise decrease timeout by time elapsed.
		 */
		if (allow_non_xm) {
			recv_until = _now() + timeout;

			if (baudrate && !*baud_changed) {
				rc = kwboot_baud_magic_handle(fd, *c, baudrate);
				if (rc == 1)
					*baud_changed = 1;
				else if (!rc)
					*non_xm_print = 1;
				else
					return rc;
			} else if (!baudrate || !*baud_changed) {
				putchar(*c);
				fflush(stdout);
				*non_xm_print = 1;
			}
		} else {
			if (stop_on_non_xm)
				break;
			timeout = recv_until - _now();
			if (timeout < 0) {
				errno = ETIMEDOUT;
				return -1;
			}
		}
	}

	return 0;
}

static int
kwboot_xm_sendblock(int fd, struct kwboot_block *block, int allow_non_xm,
		    int *done_print, int baudrate, int allow_retries)
{
	int non_xm_print, baud_changed;
	int rc, err, retries;
	char c;

	*done_print = 0;
	non_xm_print = 0;
	baud_changed = 0;

	retries = 0;
	do {
		rc = kwboot_tty_send(fd, block, sizeof(*block), 1);
		if (rc)
			goto err;

		if (allow_non_xm && !*done_print) {
			kwboot_progress(100, '.');
			kwboot_printv("Done\n");
			*done_print = 1;
		}

		rc = kwboot_xm_recv_reply(fd, &c, retries < 3,
					  retries > 8,
					  allow_non_xm, &non_xm_print,
					  baudrate, &baud_changed);
		if (rc)
			goto err;

		if (!allow_non_xm && c != ACK) {
			if (c == NAK && allow_retries && retries + 1 < 16)
				kwboot_progress(-1, '+');
			else
				kwboot_progress(-1, 'E');
		}
	} while (c == NAK && allow_retries && retries++ < 16);

	if (non_xm_print)
		kwboot_printv("\n");

	if (allow_non_xm && baudrate && !baud_changed) {
		fprintf(stderr, "Baudrate was not changed\n");
		errno = EPROTO;
		return -1;
	}

	return _xm_reply_to_error(c);
err:
	err = errno;
	kwboot_printv("\n");
	errno = err;
	return rc;
}

static int
kwboot_xm_finish(int fd)
{
	int rc, retries;
	char c;

	kwboot_printv("Finishing transfer\n");

	retries = 0;
	do {
		rc = kwboot_tty_send_char(fd, EOT);
		if (rc)
			return rc;

		rc = kwboot_xm_recv_reply(fd, &c, retries < 3,
					  retries > 8,
					  0, NULL, 0, NULL);
		if (rc)
			return rc;
	} while (c == NAK && retries++ < 16);

	return _xm_reply_to_error(c);
}

static int
kwboot_xmodem_one(int tty, int *pnum, int header, const uint8_t *data,
		  size_t size, int baudrate)
{
	int done_print = 0;
	size_t sent, left;
	int rc;

	kwboot_printv("Sending boot image %s (%zu bytes)...\n",
		      header ? "header" : "data", size);

	left = size;
	sent = 0;

	while (sent < size) {
		struct kwboot_block block;
		int last_block;
		size_t blksz;

		blksz = kwboot_xm_makeblock(&block, data, left, (*pnum)++);
		data += blksz;

		last_block = (left <= blksz);

		/*
		 * Handling of repeated xmodem packets is completely broken in
		 * Armada 385 BootROM - it completely ignores xmodem packet
		 * numbers, they are only used for checksum verification.
		 * BootROM can handle a retry of the xmodem packet only during
		 * the transmission of kwbimage header and only if BootROM
		 * itself sent NAK response to previous attempt (it does it on
		 * checksum failure). During the transmission of kwbimage data
		 * part, BootROM always expects next xmodem packet, even if it
		 * sent NAK to previous attempt - there is absolutely no way to
		 * repair incorrectly transmitted xmodem packet during kwbimage
		 * data part upload. Also, if kwboot receives non-ACK/NAK
		 * response (meaning that original BootROM response was damaged
		 * on UART) there is no way to detect if BootROM accepted xmodem
		 * packet or not and no way to check if kwboot could repeat the
		 * packet or not.
		 *
		 * Stop transfer and return failure if kwboot receives unknown
		 * reply if non-xmodem reply is not allowed (for all xmodem
		 * packets except the last header packet) or when non-ACK reply
		 * is received during data part transfer.
		 */
		rc = kwboot_xm_sendblock(tty, &block, header && last_block,
					 &done_print, baudrate, header);
		if (rc)
			goto out;

		sent += blksz;
		left -= blksz;

		if (!done_print)
			kwboot_progress(sent * 100 / size, '.');
	}

	if (!done_print)
		kwboot_printv("Done\n");

	return 0;
out:
	kwboot_printv("\n");
	return rc;
}

static int
kwboot_xmodem(int tty, const void *_img, size_t size, int baudrate)
{
	const uint8_t *img = _img;
	int rc, pnum;
	size_t hdrsz;

	hdrsz = kwbheader_size(img);

	/*
	 * If header size is not aligned to xmodem block size (which applies
	 * for all images in kwbimage v0 format) then we have to ensure that
	 * the last xmodem block of header contains beginning of the data
	 * followed by the header. So align header size to xmodem block size.
	 */
	hdrsz += (KWBOOT_XM_BLKSZ - hdrsz % KWBOOT_XM_BLKSZ) % KWBOOT_XM_BLKSZ;

	pnum = 1;

	rc = kwboot_xmodem_one(tty, &pnum, 1, img, hdrsz, baudrate);
	if (rc)
		return rc;

	/*
	 * If we have already sent image data as a part of the last
	 * xmodem header block then we have nothing more to send.
	 */
	if (hdrsz < size) {
		img += hdrsz;
		size -= hdrsz;
		rc = kwboot_xmodem_one(tty, &pnum, 0, img, size, 0);
		if (rc)
			return rc;
	}

	rc = kwboot_xm_finish(tty);
	if (rc)
		return rc;

	if (baudrate) {
		kwboot_printv("\nChanging baudrate back to 115200 Bd\n\n");
		rc = kwboot_tty_change_baudrate(tty, 115200);
		if (rc)
			return rc;
	}

	return 0;
}

static int
kwboot_term_pipe(int in, int out, const char *quit, int *s)
{
	char buf[128];
	ssize_t nin;

	nin = read(in, buf, sizeof(buf));
	if (nin <= 0)
		return -1;

	if (quit) {
		int i;

		for (i = 0; i < nin; i++) {
			if (buf[i] == quit[*s]) {
				(*s)++;
				if (!quit[*s]) {
					nin = (i > *s) ? (i - *s) : 0;
					break;
				}
			} else {
				if (*s > i && kwboot_write(out, quit, *s - i) < 0)
					return -1;
				*s = 0;
			}
		}

		if (i == nin)
			nin -= (nin > *s) ? *s : nin;
	}

	if (kwboot_write(out, buf, nin) < 0)
		return -1;

	return 0;
}

static int
kwboot_terminal(int tty)
{
	int rc, in, s;
	const char *quit = "\34c";
	struct termios otio, tio;

	rc = -1;

	in = STDIN_FILENO;
	if (isatty(in)) {
		rc = tcgetattr(in, &otio);
		if (!rc) {
			tio = otio;
			cfmakeraw(&tio);
			rc = tcsetattr(in, TCSANOW, &tio);
		}
		if (rc) {
			perror("tcsetattr");
			goto out;
		}

		kwboot_printv("[Type Ctrl-%c + %c to quit]\r\n",
			      quit[0] | 0100, quit[1]);
	} else
		in = -1;

	rc = 0;
	s = 0;

	do {
		fd_set rfds;
		int nfds = 0;

		FD_ZERO(&rfds);
		FD_SET(tty, &rfds);
		nfds = nfds < tty ? tty : nfds;

		if (in >= 0) {
			FD_SET(in, &rfds);
			nfds = nfds < in ? in : nfds;
		}

		nfds = select(nfds + 1, &rfds, NULL, NULL, NULL);
		if (nfds < 0)
			break;

		if (FD_ISSET(tty, &rfds)) {
			rc = kwboot_term_pipe(tty, STDOUT_FILENO, NULL, NULL);
			if (rc)
				break;
		}

		if (in >= 0 && FD_ISSET(in, &rfds)) {
			rc = kwboot_term_pipe(in, tty, quit, &s);
			if (rc)
				break;
		}
	} while (quit[s] != 0);

	if (in >= 0)
		tcsetattr(in, TCSANOW, &otio);
	printf("\n");
out:
	return rc;
}

static void *
kwboot_read_image(const char *path, size_t *size, size_t reserve)
{
	int rc, fd;
	struct stat st;
	void *img;
	off_t tot;

	rc = -1;
	img = NULL;

	fd = open(path, O_RDONLY);
	if (fd < 0)
		goto out;

	rc = fstat(fd, &st);
	if (rc)
		goto out;

	img = malloc(st.st_size + reserve);
	if (!img)
		goto out;

	tot = 0;
	while (tot < st.st_size) {
		ssize_t rd = read(fd, img + tot, st.st_size - tot);

		if (rd < 0)
			goto out;

		tot += rd;

		if (!rd && tot < st.st_size) {
			errno = EIO;
			goto out;
		}
	}

	rc = 0;
	*size = st.st_size;
out:
	if (rc && img) {
		free(img);
		img = NULL;
	}
	if (fd >= 0)
		close(fd);

	return img;
}

static uint8_t
kwboot_hdr_csum8(const void *hdr)
{
	const uint8_t *data = hdr;
	uint8_t csum;
	size_t size;

	size = kwbheader_size_for_csum(hdr);

	for (csum = 0; size-- > 0; data++)
		csum += *data;

	return csum;
}

static uint32_t *
kwboot_img_csum32_ptr(void *img)
{
	struct main_hdr_v1 *hdr = img;
	uint32_t datasz;

	datasz = le32_to_cpu(hdr->blocksize) - sizeof(uint32_t);

	return img + le32_to_cpu(hdr->srcaddr) + datasz;
}

static uint32_t
kwboot_img_csum32(const void *img)
{
	const struct main_hdr_v1 *hdr = img;
	uint32_t datasz, csum = 0;
	const uint32_t *data;

	datasz = le32_to_cpu(hdr->blocksize) - sizeof(csum);
	if (datasz % sizeof(uint32_t))
		return 0;

	data = img + le32_to_cpu(hdr->srcaddr);
	while (datasz > 0) {
		csum += le32_to_cpu(*data++);
		datasz -= 4;
	}

	return cpu_to_le32(csum);
}

static int
kwboot_img_is_secure(void *img)
{
	struct opt_hdr_v1 *ohdr;

	for_each_opt_hdr_v1 (ohdr, img)
		if (ohdr->headertype == OPT_HDR_V1_SECURE_TYPE)
			return 1;

	return 0;
}

static void *
kwboot_img_grow_data_right(void *img, size_t *size, size_t grow)
{
	struct main_hdr_v1 *hdr = img;
	void *result;

	/*
	 * 32-bit checksum comes after end of image code, so we will be putting
	 * new code there. So we get this pointer and then increase data size
	 * (since increasing data size changes kwboot_img_csum32_ptr() return
	 *  value).
	 */
	result = kwboot_img_csum32_ptr(img);
	hdr->blocksize = cpu_to_le32(le32_to_cpu(hdr->blocksize) + grow);
	*size += grow;

	return result;
}

static void
kwboot_img_grow_hdr(void *img, size_t *size, size_t grow)
{
	uint32_t hdrsz, datasz, srcaddr;
	struct main_hdr_v1 *hdr = img;
	struct opt_hdr_v1 *ohdr;
	uint8_t *data;

	srcaddr = le32_to_cpu(hdr->srcaddr);

	/* calculate real used space in kwbimage header */
	if (kwbimage_version(img) == 0) {
		hdrsz = kwbheader_size(img);
	} else {
		hdrsz = sizeof(*hdr);
		for_each_opt_hdr_v1 (ohdr, hdr)
			hdrsz += opt_hdr_v1_size(ohdr);
	}

	data = (uint8_t *)img + srcaddr;
	datasz = *size - srcaddr;

	/* only move data if there is not enough space */
	if (hdrsz + grow > srcaddr) {
		size_t need = hdrsz + grow - srcaddr;

		/* move data by enough bytes */
		memmove(data + need, data, datasz);

		hdr->srcaddr = cpu_to_le32(srcaddr + need);
		*size += need;
	}

	if (kwbimage_version(img) == 1) {
		hdrsz += grow;
		if (hdrsz > kwbheader_size(img)) {
			hdr->headersz_msb = hdrsz >> 16;
			hdr->headersz_lsb = cpu_to_le16(hdrsz & 0xffff);
		}
	}
}

static void *
kwboot_add_bin_ohdr_v1(void *img, size_t *size, uint32_t binsz)
{
	struct main_hdr_v1 *hdr = img;
	struct opt_hdr_v1 *ohdr;
	uint32_t num_args;
	uint32_t offset;
	uint32_t ohdrsz;
	uint8_t *prev_ext;

	if (hdr->ext) {
		for_each_opt_hdr_v1 (ohdr, img)
			if (opt_hdr_v1_next(ohdr) == NULL)
				break;

		prev_ext = opt_hdr_v1_ext(ohdr);
		ohdr = _opt_hdr_v1_next(ohdr);
	} else {
		ohdr = (void *)(hdr + 1);
		prev_ext = &hdr->ext;
	}

	/*
	 * ARM executable code inside the BIN header on some mvebu platforms
	 * (e.g. A370, AXP) must always be aligned with the 128-bit boundary.
	 * This requirement can be met by inserting dummy arguments into
	 * BIN header, if needed.
	 */
	offset = &ohdr->data[4] - (char *)img;
	num_args = ((16 - offset % 16) % 16) / sizeof(uint32_t);

	ohdrsz = sizeof(*ohdr) + 4 + 4 * num_args + binsz + 4;
	kwboot_img_grow_hdr(hdr, size, ohdrsz);

	*prev_ext = 1;

	ohdr->headertype = OPT_HDR_V1_BINARY_TYPE;
	ohdr->headersz_msb = ohdrsz >> 16;
	ohdr->headersz_lsb = cpu_to_le16(ohdrsz & 0xffff);

	memset(&ohdr->data[0], 0, ohdrsz - sizeof(*ohdr));
	*(uint32_t *)&ohdr->data[0] = cpu_to_le32(num_args);

	return &ohdr->data[4 + 4 * num_args];
}

static void
_inject_baudrate_change_code(void *img, size_t *size, int for_data,
			     int old_baud, int new_baud)
{
	struct main_hdr_v1 *hdr = img;
	uint32_t orig_datasz;
	uint32_t codesz;
	uint8_t *code;

	if (for_data) {
		orig_datasz = le32_to_cpu(hdr->blocksize) - sizeof(uint32_t);

		codesz = sizeof(kwboot_baud_code) +
			 sizeof(kwboot_baud_code_data_jump);
		code = kwboot_img_grow_data_right(img, size, codesz);
	} else {
		codesz = sizeof(kwboot_baud_code_binhdr_pre) +
			 sizeof(kwboot_baud_code) +
			 sizeof(kwboot_baud_code_binhdr_post);
		code = kwboot_add_bin_ohdr_v1(img, size, codesz);

		codesz = sizeof(kwboot_baud_code_binhdr_pre);
		memcpy(code, kwboot_baud_code_binhdr_pre, codesz);
		code += codesz;
	}

	codesz = sizeof(kwboot_baud_code) - 2 * sizeof(uint32_t);
	memcpy(code, kwboot_baud_code, codesz);
	code += codesz;
	*(uint32_t *)code = cpu_to_le32(old_baud);
	code += sizeof(uint32_t);
	*(uint32_t *)code = cpu_to_le32(new_baud);
	code += sizeof(uint32_t);

	if (for_data) {
		codesz = sizeof(kwboot_baud_code_data_jump) - sizeof(uint32_t);
		memcpy(code, kwboot_baud_code_data_jump, codesz);
		code += codesz;
		*(uint32_t *)code = hdr->execaddr;
		code += sizeof(uint32_t);
		hdr->execaddr = cpu_to_le32(le32_to_cpu(hdr->destaddr) + orig_datasz);
	} else {
		codesz = sizeof(kwboot_baud_code_binhdr_post);
		memcpy(code, kwboot_baud_code_binhdr_post, codesz);
		code += codesz;
	}
}

static int
kwboot_img_patch(void *img, size_t *size, int baudrate)
{
	struct main_hdr_v1 *hdr;
	uint32_t srcaddr;
	uint8_t csum;
	size_t hdrsz;
	int image_ver;
	int is_secure;

	hdr = img;

	if (*size < sizeof(struct main_hdr_v1))
		goto err;

	image_ver = kwbimage_version(img);
	if (image_ver != 0 && image_ver != 1) {
		fprintf(stderr, "Invalid image header version\n");
		goto err;
	}

	hdrsz = kwbheader_size(hdr);

	if (*size < hdrsz)
		goto err;

	csum = kwboot_hdr_csum8(hdr) - hdr->checksum;
	if (csum != hdr->checksum)
		goto err;

	srcaddr = le32_to_cpu(hdr->srcaddr);

	switch (hdr->blockid) {
	case IBR_HDR_SATA_ID:
		if (srcaddr < 1)
			goto err;

		hdr->srcaddr = cpu_to_le32((srcaddr - 1) * 512);
		break;

	case IBR_HDR_SDIO_ID:
		hdr->srcaddr = cpu_to_le32(srcaddr * 512);
		break;

	case IBR_HDR_PEX_ID:
		if (srcaddr == 0xFFFFFFFF)
			hdr->srcaddr = cpu_to_le32(hdrsz);
		break;

	case IBR_HDR_SPI_ID:
		if (hdr->destaddr == cpu_to_le32(0xFFFFFFFF)) {
			kwboot_printv("Patching destination and execution addresses from SPI/NOR XIP area to DDR area 0x00800000\n");
			hdr->destaddr = cpu_to_le32(0x00800000);
			hdr->execaddr = cpu_to_le32(0x00800000);
		}
		break;
	}

	if (hdrsz > le32_to_cpu(hdr->srcaddr) ||
	    *size < le32_to_cpu(hdr->srcaddr) + le32_to_cpu(hdr->blocksize))
		goto err;

	if (kwboot_img_csum32(img) != *kwboot_img_csum32_ptr(img))
		goto err;

	is_secure = kwboot_img_is_secure(img);

	if (hdr->blockid != IBR_HDR_UART_ID) {
		if (is_secure) {
			fprintf(stderr,
				"Image has secure header with signature for non-UART booting\n");
			goto err;
		}

		kwboot_printv("Patching image boot signature to UART\n");
		hdr->blockid = IBR_HDR_UART_ID;
	}

	if (!is_secure) {
		if (image_ver == 1) {
			/*
			 * Tell BootROM to send BootROM messages to UART port
			 * number 0 (used also for UART booting) with default
			 * baudrate (which should be 115200) and do not touch
			 * UART MPP configuration.
			 */
			hdr->flags |= 0x1;
			hdr->options &= ~0x1F;
			hdr->options |= MAIN_HDR_V1_OPT_BAUD_DEFAULT;
			hdr->options |= 0 << 3;
		}
		if (image_ver == 0)
			((struct main_hdr_v0 *)img)->nandeccmode = IBR_HDR_ECC_DISABLED;
		hdr->nandpagesize = 0;
	}

	if (baudrate) {
		if (image_ver == 0) {
			fprintf(stderr,
				"Cannot inject code for changing baudrate into v0 image header\n");
			goto err;
		}

		if (is_secure) {
			fprintf(stderr,
				"Cannot inject code for changing baudrate into image with secure header\n");
			goto err;
		}

		/*
		 * First inject code that changes the baudrate from the default
		 * value of 115200 Bd to requested value. This code is inserted
		 * as a new opt hdr, so it is executed by BootROM after the
		 * header part is received.
		 */
		kwboot_printv("Injecting binary header code for changing baudrate to %d Bd\n",
			      baudrate);
		_inject_baudrate_change_code(img, size, 0, 115200, baudrate);

		/*
		 * Now inject code that changes the baudrate back to 115200 Bd.
		 * This code is appended after the data part of the image, and
		 * execaddr is changed so that it is executed before U-Boot
		 * proper.
		 */
		kwboot_printv("Injecting code for changing baudrate back\n");
		_inject_baudrate_change_code(img, size, 1, baudrate, 115200);

		/* Update the 32-bit data checksum */
		*kwboot_img_csum32_ptr(img) = kwboot_img_csum32(img);

		/* recompute header size */
		hdrsz = kwbheader_size(hdr);
	}

	if (hdrsz % KWBOOT_XM_BLKSZ) {
		size_t grow = KWBOOT_XM_BLKSZ - hdrsz % KWBOOT_XM_BLKSZ;

		if (is_secure) {
			fprintf(stderr, "Cannot align image with secure header\n");
			goto err;
		}

		kwboot_printv("Aligning image header to Xmodem block size\n");
		kwboot_img_grow_hdr(img, size, grow);
	}

	hdr->checksum = kwboot_hdr_csum8(hdr) - csum;

	*size = le32_to_cpu(hdr->srcaddr) + le32_to_cpu(hdr->blocksize);
	return 0;
err:
	errno = EINVAL;
	return -1;
}

static void
kwboot_usage(FILE *stream, char *progname)
{
	fprintf(stream,
		"Usage: %s [OPTIONS] [-b <image> | -D <image> ] [-B <baud> ] <TTY>\n",
		progname);
	fprintf(stream, "\n");
	fprintf(stream,
		"  -b <image>: boot <image> with preamble (Kirkwood, Armada 370/XP)\n");
	fprintf(stream,
		"  -D <image>: boot <image> without preamble (Dove)\n");
	fprintf(stream, "  -d: enter debug mode\n");
	fprintf(stream, "  -a: use timings for Armada XP\n");
	fprintf(stream, "  -s <resp-timeo>: use specific response-timeout\n");
	fprintf(stream,
		"  -o <block-timeo>: use specific xmodem block timeout\n");
	fprintf(stream, "\n");
	fprintf(stream, "  -t: mini terminal\n");
	fprintf(stream, "\n");
	fprintf(stream, "  -B <baud>: set baud rate\n");
	fprintf(stream, "\n");
}

int
main(int argc, char **argv)
{
	const char *ttypath, *imgpath;
	int rv, rc, tty, term;
	void *bootmsg;
	void *debugmsg;
	void *img;
	size_t size;
	size_t after_img_rsv;
	int baudrate;
	int prev_optind;
	int c;

	rv = 1;
	tty = -1;
	bootmsg = NULL;
	debugmsg = NULL;
	imgpath = NULL;
	img = NULL;
	term = 0;
	size = 0;
	after_img_rsv = KWBOOT_XM_BLKSZ;
	baudrate = 115200;

	printf("kwboot version %s\n", PLAIN_VERSION);

	kwboot_verbose = isatty(STDOUT_FILENO);

	do {
		prev_optind = optind;
		c = getopt(argc, argv, "hbptaB:dD:q:s:o:");
		if (c < 0)
			break;

		switch (c) {
		case 'b':
			if (imgpath || bootmsg || debugmsg)
				goto usage;
			bootmsg = kwboot_msg_boot;
			if (prev_optind == optind)
				goto usage;
			if (optind < argc - 1 && argv[optind] && argv[optind][0] != '-')
				imgpath = argv[optind++];
			break;

		case 'D':
			if (imgpath || bootmsg || debugmsg)
				goto usage;
			bootmsg = NULL;
			imgpath = optarg;
			break;

		case 'd':
			if (imgpath || bootmsg || debugmsg)
				goto usage;
			debugmsg = kwboot_msg_debug;
			break;

		case 'p':
			/* nop, for backward compatibility */
			break;

		case 't':
			term = 1;
			break;

		case 'a':
			msg_rsp_timeo = KWBOOT_MSG_RSP_TIMEO_AXP;
			break;

		case 'q':
			/* nop, for backward compatibility */
			break;

		case 's':
			msg_rsp_timeo = atoi(optarg);
			break;

		case 'o':
			blk_rsp_timeo = atoi(optarg);
			break;

		case 'B':
			baudrate = atoi(optarg);
			break;

		case 'h':
			rv = 0;
		default:
			goto usage;
		}
	} while (1);

	if (!bootmsg && !term && !debugmsg && !imgpath)
		goto usage;

	ttypath = argv[optind++];

	if (optind != argc)
		goto usage;

	tty = kwboot_open_tty(ttypath, imgpath ? 115200 : baudrate);
	if (tty < 0) {
		perror(ttypath);
		goto out;
	}

	if (baudrate == 115200)
		/* do not change baudrate during Xmodem to the same value */
		baudrate = 0;
	else
		/* ensure we have enough space for baudrate change code */
		after_img_rsv += sizeof(struct opt_hdr_v1) + 8 + 16 +
				 sizeof(kwboot_baud_code_binhdr_pre) +
				 sizeof(kwboot_baud_code) +
				 sizeof(kwboot_baud_code_binhdr_post) +
				 KWBOOT_XM_BLKSZ +
				 sizeof(kwboot_baud_code) +
				 sizeof(kwboot_baud_code_data_jump) +
				 KWBOOT_XM_BLKSZ;

	if (imgpath) {
		img = kwboot_read_image(imgpath, &size, after_img_rsv);
		if (!img) {
			perror(imgpath);
			goto out;
		}

		rc = kwboot_img_patch(img, &size, baudrate);
		if (rc) {
			fprintf(stderr, "%s: Invalid image.\n", imgpath);
			goto out;
		}
	}

	if (debugmsg) {
		rc = kwboot_debugmsg(tty, debugmsg);
		if (rc) {
			perror("debugmsg");
			goto out;
		}
	} else if (bootmsg) {
		rc = kwboot_bootmsg(tty, bootmsg);
		if (rc) {
			perror("bootmsg");
			goto out;
		}
	}

	if (img) {
		rc = kwboot_xmodem(tty, img, size, baudrate);
		if (rc) {
			perror("xmodem");
			goto out;
		}
	}

	if (term) {
		rc = kwboot_terminal(tty);
		if (rc && !(errno == EINTR)) {
			perror("terminal");
			goto out;
		}
	}

	rv = 0;
out:
	if (tty >= 0)
		close(tty);

	if (img)
		free(img);

	return rv;

usage:
	kwboot_usage(rv ? stderr : stdout, basename(argv[0]));
	goto out;
}