aboutsummaryrefslogtreecommitdiffstats
path: root/arch/mips/kernel/vpe.c
blob: 3efcb065f78a4fcc9a55a842f7574ceb89d43f7a (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
/*
 * Copyright (C) 2004, 2005 MIPS Technologies, Inc.  All rights reserved.
 *
 *  This program is free software; you can distribute it and/or modify it
 *  under the terms of the GNU General Public License (Version 2) as
 *  published by the Free Software Foundation.
 *
 *  This program is distributed in the hope it will be useful, but WITHOUT
 *  ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 *  FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
 *  for more details.
 *
 *  You should have received a copy of the GNU General Public License along
 *  with this program; if not, write to the Free Software Foundation, Inc.,
 *  59 Temple Place - Suite 330, Boston MA 02111-1307, USA.
 */

/*
 * VPE support module
 *
 * Provides support for loading a MIPS SP program on VPE1.
 * The SP environment is rather simple, no tlb's.  It needs to be relocatable
 * (or partially linked). You should initialise your stack in the startup
 * code. This loader looks for the symbol __start and sets up
 * execution to resume from there. The MIPS SDE kit contains suitable examples.
 *
 * To load and run, simply cat a SP 'program file' to /dev/vpe1.
 * i.e cat spapp >/dev/vpe1.
 */
#include <linux/kernel.h>
#include <linux/device.h>
#include <linux/module.h>
#include <linux/fs.h>
#include <linux/init.h>
#include <asm/uaccess.h>
#include <linux/slab.h>
#include <linux/list.h>
#include <linux/vmalloc.h>
#include <linux/elf.h>
#include <linux/seq_file.h>
#include <linux/syscalls.h>
#include <linux/moduleloader.h>
#include <linux/interrupt.h>
#include <linux/poll.h>
#include <linux/bootmem.h>
#include <asm/mipsregs.h>
#include <asm/mipsmtregs.h>
#include <asm/cacheflush.h>
#include <linux/atomic.h>
#include <asm/cpu.h>
#include <asm/mips_mt.h>
#include <asm/processor.h>
#include <asm/system.h>
#include <asm/vpe.h>
#include <asm/kspd.h>

typedef void *vpe_handle;

#ifndef ARCH_SHF_SMALL
#define ARCH_SHF_SMALL 0
#endif

/* If this is set, the section belongs in the init part of the module */
#define INIT_OFFSET_MASK (1UL << (BITS_PER_LONG-1))

/*
 * The number of TCs and VPEs physically available on the core
 */
static int hw_tcs, hw_vpes;
static char module_name[] = "vpe";
static int major;
static const int minor = 1;	/* fixed for now  */

#ifdef CONFIG_MIPS_APSP_KSPD
static struct kspd_notifications kspd_events;
static int kspd_events_reqd;
#endif

/* grab the likely amount of memory we will need. */
#ifdef CONFIG_MIPS_VPE_LOADER_TOM
#define P_SIZE (2 * 1024 * 1024)
#else
/* add an overhead to the max kmalloc size for non-striped symbols/etc */
#define P_SIZE (256 * 1024)
#endif

extern unsigned long physical_memsize;

#define MAX_VPES 16
#define VPE_PATH_MAX 256

enum vpe_state {
	VPE_STATE_UNUSED = 0,
	VPE_STATE_INUSE,
	VPE_STATE_RUNNING
};

enum tc_state {
	TC_STATE_UNUSED = 0,
	TC_STATE_INUSE,
	TC_STATE_RUNNING,
	TC_STATE_DYNAMIC
};

struct vpe {
	enum vpe_state state;

	/* (device) minor associated with this vpe */
	int minor;

	/* elfloader stuff */
	void *load_addr;
	unsigned long len;
	char *pbuffer;
	unsigned long plen;
	unsigned int uid, gid;
	char cwd[VPE_PATH_MAX];

	unsigned long __start;

	/* tc's associated with this vpe */
	struct list_head tc;

	/* The list of vpe's */
	struct list_head list;

	/* shared symbol address */
	void *shared_ptr;

	/* the list of who wants to know when something major happens */
	struct list_head notify;

	unsigned int ntcs;
};

struct tc {
	enum tc_state state;
	int index;

	struct vpe *pvpe;	/* parent VPE */
	struct list_head tc;	/* The list of TC's with this VPE */
	struct list_head list;	/* The global list of tc's */
};

struct {
	spinlock_t vpe_list_lock;
	struct list_head vpe_list;	/* Virtual processing elements */
	spinlock_t tc_list_lock;
	struct list_head tc_list;	/* Thread contexts */
} vpecontrol = {
	.vpe_list_lock	= __SPIN_LOCK_UNLOCKED(vpe_list_lock),
	.vpe_list	= LIST_HEAD_INIT(vpecontrol.vpe_list),
	.tc_list_lock	= __SPIN_LOCK_UNLOCKED(tc_list_lock),
	.tc_list	= LIST_HEAD_INIT(vpecontrol.tc_list)
};

static void release_progmem(void *ptr);

/* get the vpe associated with this minor */
static struct vpe *get_vpe(int minor)
{
	struct vpe *res, *v;

	if (!cpu_has_mipsmt)
		return NULL;

	res = NULL;
	spin_lock(&vpecontrol.vpe_list_lock);
	list_for_each_entry(v, &vpecontrol.vpe_list, list) {
		if (v->minor == minor) {
			res = v;
			break;
		}
	}
	spin_unlock(&vpecontrol.vpe_list_lock);

	return res;
}

/* get the vpe associated with this minor */
static struct tc *get_tc(int index)
{
	struct tc *res, *t;

	res = NULL;
	spin_lock(&vpecontrol.tc_list_lock);
	list_for_each_entry(t, &vpecontrol.tc_list, list) {
		if (t->index == index) {
			res = t;
			break;
		}
	}
	spin_unlock(&vpecontrol.tc_list_lock);

	return res;
}

/* allocate a vpe and associate it with this minor (or index) */
static struct vpe *alloc_vpe(int minor)
{
	struct vpe *v;

	if ((v = kzalloc(sizeof(struct vpe), GFP_KERNEL)) == NULL)
		return NULL;

	INIT_LIST_HEAD(&v->tc);
	spin_lock(&vpecontrol.vpe_list_lock);
	list_add_tail(&v->list, &vpecontrol.vpe_list);
	spin_unlock(&vpecontrol.vpe_list_lock);

	INIT_LIST_HEAD(&v->notify);
	v->minor = minor;

	return v;
}

/* allocate a tc. At startup only tc0 is running, all other can be halted. */
static struct tc *alloc_tc(int index)
{
	struct tc *tc;

	if ((tc = kzalloc(sizeof(struct tc), GFP_KERNEL)) == NULL)
		goto out;

	INIT_LIST_HEAD(&tc->tc);
	tc->index = index;

	spin_lock(&vpecontrol.tc_list_lock);
	list_add_tail(&tc->list, &vpecontrol.tc_list);
	spin_unlock(&vpecontrol.tc_list_lock);

out:
	return tc;
}

/* clean up and free everything */
static void release_vpe(struct vpe *v)
{
	list_del(&v->list);
	if (v->load_addr)
		release_progmem(v);
	kfree(v);
}

static void __maybe_unused dump_mtregs(void)
{
	unsigned long val;

	val = read_c0_config3();
	printk("config3 0x%lx MT %ld\n", val,
	       (val & CONFIG3_MT) >> CONFIG3_MT_SHIFT);

	val = read_c0_mvpcontrol();
	printk("MVPControl 0x%lx, STLB %ld VPC %ld EVP %ld\n", val,
	       (val & MVPCONTROL_STLB) >> MVPCONTROL_STLB_SHIFT,
	       (val & MVPCONTROL_VPC) >> MVPCONTROL_VPC_SHIFT,
	       (val & MVPCONTROL_EVP));

	val = read_c0_mvpconf0();
	printk("mvpconf0 0x%lx, PVPE %ld PTC %ld M %ld\n", val,
	       (val & MVPCONF0_PVPE) >> MVPCONF0_PVPE_SHIFT,
	       val & MVPCONF0_PTC, (val & MVPCONF0_M) >> MVPCONF0_M_SHIFT);
}

/* Find some VPE program space  */
static void *alloc_progmem(unsigned long len)
{
	void *addr;

#ifdef CONFIG_MIPS_VPE_LOADER_TOM
	/*
	 * This means you must tell Linux to use less memory than you
	 * physically have, for example by passing a mem= boot argument.
	 */
	addr = pfn_to_kaddr(max_low_pfn);
	memset(addr, 0, len);
#else
	/* simple grab some mem for now */
	addr = kzalloc(len, GFP_KERNEL);
#endif

	return addr;
}

static void release_progmem(void *ptr)
{
#ifndef CONFIG_MIPS_VPE_LOADER_TOM
	kfree(ptr);
#endif
}

/* Update size with this section: return offset. */
static long get_offset(unsigned long *size, Elf_Shdr * sechdr)
{
	long ret;

	ret = ALIGN(*size, sechdr->sh_addralign ? : 1);
	*size = ret + sechdr->sh_size;
	return ret;
}

/* Lay out the SHF_ALLOC sections in a way not dissimilar to how ld
   might -- code, read-only data, read-write data, small data.  Tally
   sizes, and place the offsets into sh_entsize fields: high bit means it
   belongs in init. */
static void layout_sections(struct module *mod, const Elf_Ehdr * hdr,
			    Elf_Shdr * sechdrs, const char *secstrings)
{
	static unsigned long const masks[][2] = {
		/* NOTE: all executable code must be the first section
		 * in this array; otherwise modify the text_size
		 * finder in the two loops below */
		{SHF_EXECINSTR | SHF_ALLOC, ARCH_SHF_SMALL},
		{SHF_ALLOC, SHF_WRITE | ARCH_SHF_SMALL},
		{SHF_WRITE | SHF_ALLOC, ARCH_SHF_SMALL},
		{ARCH_SHF_SMALL | SHF_ALLOC, 0}
	};
	unsigned int m, i;

	for (i = 0; i < hdr->e_shnum; i++)
		sechdrs[i].sh_entsize = ~0UL;

	for (m = 0; m < ARRAY_SIZE(masks); ++m) {
		for (i = 0; i < hdr->e_shnum; ++i) {
			Elf_Shdr *s = &sechdrs[i];

			//  || strncmp(secstrings + s->sh_name, ".init", 5) == 0)
			if ((s->sh_flags & masks[m][0]) != masks[m][0]
			    || (s->sh_flags & masks[m][1])
			    || s->sh_entsize != ~0UL)
				continue;
			s->sh_entsize =
				get_offset((unsigned long *)&mod->core_size, s);
		}

		if (m == 0)
			mod->core_text_size = mod->core_size;

	}
}


/* from module-elf32.c, but subverted a little */

struct mips_hi16 {
	struct mips_hi16 *next;
	Elf32_Addr *addr;
	Elf32_Addr value;
};

static struct mips_hi16 *mips_hi16_list;
static unsigned int gp_offs, gp_addr;

static int apply_r_mips_none(struct module *me, uint32_t *location,
			     Elf32_Addr v)
{
	return 0;
}

static int apply_r_mips_gprel16(struct module *me, uint32_t *location,
				Elf32_Addr v)
{
	int rel;

	if( !(*location & 0xffff) ) {
		rel = (int)v - gp_addr;
	}
	else {
		/* .sbss + gp(relative) + offset */
		/* kludge! */
		rel =  (int)(short)((int)v + gp_offs +
				    (int)(short)(*location & 0xffff) - gp_addr);
	}

	if( (rel > 32768) || (rel < -32768) ) {
		printk(KERN_DEBUG "VPE loader: apply_r_mips_gprel16: "
		       "relative address 0x%x out of range of gp register\n",
		       rel);
		return -ENOEXEC;
	}

	*location = (*location & 0xffff0000) | (rel & 0xffff);

	return 0;
}

static int apply_r_mips_pc16(struct module *me, uint32_t *location,
			     Elf32_Addr v)
{
	int rel;
	rel = (((unsigned int)v - (unsigned int)location));
	rel >>= 2;		// because the offset is in _instructions_ not bytes.
	rel -= 1;		// and one instruction less due to the branch delay slot.

	if( (rel > 32768) || (rel < -32768) ) {
		printk(KERN_DEBUG "VPE loader: "
 		       "apply_r_mips_pc16: relative address out of range 0x%x\n", rel);
		return -ENOEXEC;
	}

	*location = (*location & 0xffff0000) | (rel & 0xffff);

	return 0;
}

static int apply_r_mips_32(struct module *me, uint32_t *location,
			   Elf32_Addr v)
{
	*location += v;

	return 0;
}

static int apply_r_mips_26(struct module *me, uint32_t *location,
			   Elf32_Addr v)
{
	if (v % 4) {
		printk(KERN_DEBUG "VPE loader: apply_r_mips_26 "
		       " unaligned relocation\n");
		return -ENOEXEC;
	}

/*
 * Not desperately convinced this is a good check of an overflow condition
 * anyway. But it gets in the way of handling undefined weak symbols which
 * we want to set to zero.
 * if ((v & 0xf0000000) != (((unsigned long)location + 4) & 0xf0000000)) {
 * printk(KERN_ERR
 * "module %s: relocation overflow\n",
 * me->name);
 * return -ENOEXEC;
 * }
 */

	*location = (*location & ~0x03ffffff) |
		((*location + (v >> 2)) & 0x03ffffff);
	return 0;
}

static int apply_r_mips_hi16(struct module *me, uint32_t *location,
			     Elf32_Addr v)
{
	struct mips_hi16 *n;

	/*
	 * We cannot relocate this one now because we don't know the value of
	 * the carry we need to add.  Save the information, and let LO16 do the
	 * actual relocation.
	 */
	n = kmalloc(sizeof *n, GFP_KERNEL);
	if (!n)
		return -ENOMEM;

	n->addr = location;
	n->value = v;
	n->next = mips_hi16_list;
	mips_hi16_list = n;

	return 0;
}

static int apply_r_mips_lo16(struct module *me, uint32_t *location,
			     Elf32_Addr v)
{
	unsigned long insnlo = *location;
	Elf32_Addr val, vallo;
	struct mips_hi16 *l, *next;

	/* Sign extend the addend we extract from the lo insn.  */
	vallo = ((insnlo & 0xffff) ^ 0x8000) - 0x8000;

	if (mips_hi16_list != NULL) {

		l = mips_hi16_list;
		while (l != NULL) {
			unsigned long insn;

			/*
			 * The value for the HI16 had best be the same.
			 */
 			if (v != l->value) {
				printk(KERN_DEBUG "VPE loader: "
				       "apply_r_mips_lo16/hi16: \t"
				       "inconsistent value information\n");
				goto out_free;
			}

			/*
			 * Do the HI16 relocation.  Note that we actually don't
			 * need to know anything about the LO16 itself, except
			 * where to find the low 16 bits of the addend needed
			 * by the LO16.
			 */
			insn = *l->addr;
			val = ((insn & 0xffff) << 16) + vallo;
			val += v;

			/*
			 * Account for the sign extension that will happen in
			 * the low bits.
			 */
			val = ((val >> 16) + ((val & 0x8000) != 0)) & 0xffff;

			insn = (insn & ~0xffff) | val;
			*l->addr = insn;

			next = l->next;
			kfree(l);
			l = next;
		}

		mips_hi16_list = NULL;
	}

	/*
	 * Ok, we're done with the HI16 relocs.  Now deal with the LO16.
	 */
	val = v + vallo;
	insnlo = (insnlo & ~0xffff) | (val & 0xffff);
	*location = insnlo;

	return 0;

out_free:
	while (l != NULL) {
		next = l->next;
		kfree(l);
		l = next;
	}
	mips_hi16_list = NULL;

	return -ENOEXEC;
}

static int (*reloc_handlers[]) (struct module *me, uint32_t *location,
				Elf32_Addr v) = {
	[R_MIPS_NONE]	= apply_r_mips_none,
	[R_MIPS_32]	= apply_r_mips_32,
	[R_MIPS_26]	= apply_r_mips_26,
	[R_MIPS_HI16]	= apply_r_mips_hi16,
	[R_MIPS_LO16]	= apply_r_mips_lo16,
	[R_MIPS_GPREL16] = apply_r_mips_gprel16,
	[R_MIPS_PC16] = apply_r_mips_pc16
};

static char *rstrs[] = {
	[R_MIPS_NONE]	= "MIPS_NONE",
	[R_MIPS_32]	= "MIPS_32",
	[R_MIPS_26]	= "MIPS_26",
	[R_MIPS_HI16]	= "MIPS_HI16",
	[R_MIPS_LO16]	= "MIPS_LO16",
	[R_MIPS_GPREL16] = "MIPS_GPREL16",
	[R_MIPS_PC16] = "MIPS_PC16"
};

static int apply_relocations(Elf32_Shdr *sechdrs,
		      const char *strtab,
		      unsigned int symindex,
		      unsigned int relsec,
		      struct module *me)
{
	Elf32_Rel *rel = (void *) sechdrs[relsec].sh_addr;
	Elf32_Sym *sym;
	uint32_t *location;
	unsigned int i;
	Elf32_Addr v;
	int res;

	for (i = 0; i < sechdrs[relsec].sh_size / sizeof(*rel); i++) {
		Elf32_Word r_info = rel[i].r_info;

		/* This is where to make the change */
		location = (void *)sechdrs[sechdrs[relsec].sh_info].sh_addr
			+ rel[i].r_offset;
		/* This is the symbol it is referring to */
		sym = (Elf32_Sym *)sechdrs[symindex].sh_addr
			+ ELF32_R_SYM(r_info);

		if (!sym->st_value) {
			printk(KERN_DEBUG "%s: undefined weak symbol %s\n",
			       me->name, strtab + sym->st_name);
			/* just print the warning, dont barf */
		}

		v = sym->st_value;

		res = reloc_handlers[ELF32_R_TYPE(r_info)](me, location, v);
		if( res ) {
			char *r = rstrs[ELF32_R_TYPE(r_info)];
		    	printk(KERN_WARNING "VPE loader: .text+0x%x "
			       "relocation type %s for symbol \"%s\" failed\n",
			       rel[i].r_offset, r ? r : "UNKNOWN",
			       strtab + sym->st_name);
			return res;
		}
	}

	return 0;
}

static inline void save_gp_address(unsigned int secbase, unsigned int rel)
{
	gp_addr = secbase + rel;
	gp_offs = gp_addr - (secbase & 0xffff0000);
}
/* end module-elf32.c */



/* Change all symbols so that sh_value encodes the pointer directly. */
static void simplify_symbols(Elf_Shdr * sechdrs,
			    unsigned int symindex,
			    const char *strtab,
			    const char *secstrings,
			    unsigned int nsecs, struct module *mod)
{
	Elf_Sym *sym = (void *)sechdrs[symindex].sh_addr;
	unsigned long secbase, bssbase = 0;
	unsigned int i, n = sechdrs[symindex].sh_size / sizeof(Elf_Sym);
	int size;

	/* find the .bss section for COMMON symbols */
	for (i = 0; i < nsecs; i++) {
		if (strncmp(secstrings + sechdrs[i].sh_name, ".bss", 4) == 0) {
			bssbase = sechdrs[i].sh_addr;
			break;
		}
	}

	for (i = 1; i < n; i++) {
		switch (sym[i].st_shndx) {
		case SHN_COMMON:
			/* Allocate space for the symbol in the .bss section.
			   st_value is currently size.
			   We want it to have the address of the symbol. */

			size = sym[i].st_value;
			sym[i].st_value = bssbase;

			bssbase += size;
			break;

		case SHN_ABS:
			/* Don't need to do anything */
			break;

		case SHN_UNDEF:
			/* ret = -ENOENT; */
			break;

		case SHN_MIPS_SCOMMON:
			printk(KERN_DEBUG "simplify_symbols: ignoring SHN_MIPS_SCOMMON "
			       "symbol <%s> st_shndx %d\n", strtab + sym[i].st_name,
			       sym[i].st_shndx);
			// .sbss section
			break;

		default:
			secbase = sechdrs[sym[i].st_shndx].sh_addr;

			if (strncmp(strtab + sym[i].st_name, "_gp", 3) == 0) {
				save_gp_address(secbase, sym[i].st_value);
			}

			sym[i].st_value += secbase;
			break;
		}
	}
}

#ifdef DEBUG_ELFLOADER
static void dump_elfsymbols(Elf_Shdr * sechdrs, unsigned int symindex,
			    const char *strtab, struct module *mod)
{
	Elf_Sym *sym = (void *)sechdrs[symindex].sh_addr;
	unsigned int i, n = sechdrs[symindex].sh_size / sizeof(Elf_Sym);

	printk(KERN_DEBUG "dump_elfsymbols: n %d\n", n);
	for (i = 1; i < n; i++) {
		printk(KERN_DEBUG " i %d name <%s> 0x%x\n", i,
		       strtab + sym[i].st_name, sym[i].st_value);
	}
}
#endif

/* We are prepared so configure and start the VPE... */
static int vpe_run(struct vpe * v)
{
	unsigned long flags, val, dmt_flag;
	struct vpe_notifications *n;
	unsigned int vpeflags;
	struct tc *t;

	/* check we are the Master VPE */
	local_irq_save(flags);
	val = read_c0_vpeconf0();
	if (!(val & VPECONF0_MVP)) {
		printk(KERN_WARNING
		       "VPE loader: only Master VPE's are allowed to configure MT\n");
		local_irq_restore(flags);

		return -1;
	}

	dmt_flag = dmt();
	vpeflags = dvpe();

	if (!list_empty(&v->tc)) {
		if ((t = list_entry(v->tc.next, struct tc, tc)) == NULL) {
			evpe(vpeflags);
			emt(dmt_flag);
			local_irq_restore(flags);

			printk(KERN_WARNING
			       "VPE loader: TC %d is already in use.\n",
                               t->index);
			return -ENOEXEC;
		}
	} else {
		evpe(vpeflags);
		emt(dmt_flag);
		local_irq_restore(flags);

		printk(KERN_WARNING
		       "VPE loader: No TC's associated with VPE %d\n",
		       v->minor);

		return -ENOEXEC;
	}

	/* Put MVPE's into 'configuration state' */
	set_c0_mvpcontrol(MVPCONTROL_VPC);

	settc(t->index);

	/* should check it is halted, and not activated */
	if ((read_tc_c0_tcstatus() & TCSTATUS_A) || !(read_tc_c0_tchalt() & TCHALT_H)) {
		evpe(vpeflags);
		emt(dmt_flag);
		local_irq_restore(flags);

		printk(KERN_WARNING "VPE loader: TC %d is already active!\n",
		       t->index);

		return -ENOEXEC;
	}

	/* Write the address we want it to start running from in the TCPC register. */
	write_tc_c0_tcrestart((unsigned long)v->__start);
	write_tc_c0_tccontext((unsigned long)0);

	/*
	 * Mark the TC as activated, not interrupt exempt and not dynamically
	 * allocatable
	 */
	val = read_tc_c0_tcstatus();
	val = (val & ~(TCSTATUS_DA | TCSTATUS_IXMT)) | TCSTATUS_A;
	write_tc_c0_tcstatus(val);

	write_tc_c0_tchalt(read_tc_c0_tchalt() & ~TCHALT_H);

	/*
	 * The sde-kit passes 'memsize' to __start in $a3, so set something
	 * here...  Or set $a3 to zero and define DFLT_STACK_SIZE and
	 * DFLT_HEAP_SIZE when you compile your program
	 */
	mttgpr(6, v->ntcs);
	mttgpr(7, physical_memsize);

	/* set up VPE1 */
	/*
	 * bind the TC to VPE 1 as late as possible so we only have the final
	 * VPE registers to set up, and so an EJTAG probe can trigger on it
	 */
	write_tc_c0_tcbind((read_tc_c0_tcbind() & ~TCBIND_CURVPE) | 1);

	write_vpe_c0_vpeconf0(read_vpe_c0_vpeconf0() & ~(VPECONF0_VPA));

	back_to_back_c0_hazard();

	/* Set up the XTC bit in vpeconf0 to point at our tc */
	write_vpe_c0_vpeconf0( (read_vpe_c0_vpeconf0() & ~(VPECONF0_XTC))
	                      | (t->index << VPECONF0_XTC_SHIFT));

	back_to_back_c0_hazard();

	/* enable this VPE */
	write_vpe_c0_vpeconf0(read_vpe_c0_vpeconf0() | VPECONF0_VPA);

	/* clear out any left overs from a previous program */
	write_vpe_c0_status(0);
	write_vpe_c0_cause(0);

	/* take system out of configuration state */
	clear_c0_mvpcontrol(MVPCONTROL_VPC);

	/*
	 * SMTC/SMVP kernels manage VPE enable independently,
	 * but uniprocessor kernels need to turn it on, even
	 * if that wasn't the pre-dvpe() state.
	 */
#ifdef CONFIG_SMP
	evpe(vpeflags);
#else
	evpe(EVPE_ENABLE);
#endif
	emt(dmt_flag);
	local_irq_restore(flags);

	list_for_each_entry(n, &v->notify, list)
		n->start(minor);

	return 0;
}

static int find_vpe_symbols(struct vpe * v, Elf_Shdr * sechdrs,
				      unsigned int symindex, const char *strtab,
				      struct module *mod)
{
	Elf_Sym *sym = (void *)sechdrs[symindex].sh_addr;
	unsigned int i, n = sechdrs[symindex].sh_size / sizeof(Elf_Sym);

	for (i = 1; i < n; i++) {
		if (strcmp(strtab + sym[i].st_name, "__start") == 0) {
			v->__start = sym[i].st_value;
		}

		if (strcmp(strtab + sym[i].st_name, "vpe_shared") == 0) {
			v->shared_ptr = (void *)sym[i].st_value;
		}
	}

	if ( (v->__start == 0) || (v->shared_ptr == NULL))
		return -1;

	return 0;
}

/*
 * Allocates a VPE with some program code space(the load address), copies the
 * contents of the program (p)buffer performing relocatations/etc, free's it
 * when finished.
 */
static int vpe_elfload(struct vpe * v)
{
	Elf_Ehdr *hdr;
	Elf_Shdr *sechdrs;
	long err = 0;
	char *secstrings, *strtab = NULL;
	unsigned int len, i, symindex = 0, strindex = 0, relocate = 0;
	struct module mod;	// so we can re-use the relocations code

	memset(&mod, 0, sizeof(struct module));
	strcpy(mod.name, "VPE loader");

	hdr = (Elf_Ehdr *) v->pbuffer;
	len = v->plen;

	/* Sanity checks against insmoding binaries or wrong arch,
	   weird elf version */
	if (memcmp(hdr->e_ident, ELFMAG, SELFMAG) != 0
	    || (hdr->e_type != ET_REL && hdr->e_type != ET_EXEC)
	    || !elf_check_arch(hdr)
	    || hdr->e_shentsize != sizeof(*sechdrs)) {
		printk(KERN_WARNING
		       "VPE loader: program wrong arch or weird elf version\n");

		return -ENOEXEC;
	}

	if (hdr->e_type == ET_REL)
		relocate = 1;

	if (len < hdr->e_shoff + hdr->e_shnum * sizeof(Elf_Shdr)) {
		printk(KERN_ERR "VPE loader: program length %u truncated\n",
		       len);

		return -ENOEXEC;
	}

	/* Convenience variables */
	sechdrs = (void *)hdr + hdr->e_shoff;
	secstrings = (void *)hdr + sechdrs[hdr->e_shstrndx].sh_offset;
	sechdrs[0].sh_addr = 0;

	/* And these should exist, but gcc whinges if we don't init them */
	symindex = strindex = 0;

	if (relocate) {
		for (i = 1; i < hdr->e_shnum; i++) {
			if (sechdrs[i].sh_type != SHT_NOBITS
			    && len < sechdrs[i].sh_offset + sechdrs[i].sh_size) {
				printk(KERN_ERR "VPE program length %u truncated\n",
				       len);
				return -ENOEXEC;
			}

			/* Mark all sections sh_addr with their address in the
			   temporary image. */
			sechdrs[i].sh_addr = (size_t) hdr + sechdrs[i].sh_offset;

			/* Internal symbols and strings. */
			if (sechdrs[i].sh_type == SHT_SYMTAB) {
				symindex = i;
				strindex = sechdrs[i].sh_link;
				strtab = (char *)hdr + sechdrs[strindex].sh_offset;
			}
		}
		layout_sections(&mod, hdr, sechdrs, secstrings);
	}

	v->load_addr = alloc_progmem(mod.core_size);
	if (!v->load_addr)
		return -ENOMEM;

	pr_info("VPE loader: loading to %p\n", v->load_addr);

	if (relocate) {
		for (i = 0; i < hdr->e_shnum; i++) {
			void *dest;

			if (!(sechdrs[i].sh_flags & SHF_ALLOC))
				continue;

			dest = v->load_addr + sechdrs[i].sh_entsize;

			if (sechdrs[i].sh_type != SHT_NOBITS)
				memcpy(dest, (void *)sechdrs[i].sh_addr,
				       sechdrs[i].sh_size);
			/* Update sh_addr to point to copy in image. */
			sechdrs[i].sh_addr = (unsigned long)dest;

			printk(KERN_DEBUG " section sh_name %s sh_addr 0x%x\n",
			       secstrings + sechdrs[i].sh_name, sechdrs[i].sh_addr);
		}

 		/* Fix up syms, so that st_value is a pointer to location. */
 		simplify_symbols(sechdrs, symindex, strtab, secstrings,
 				 hdr->e_shnum, &mod);

 		/* Now do relocations. */
 		for (i = 1; i < hdr->e_shnum; i++) {
 			const char *strtab = (char *)sechdrs[strindex].sh_addr;
 			unsigned int info = sechdrs[i].sh_info;

 			/* Not a valid relocation section? */
 			if (info >= hdr->e_shnum)
 				continue;

 			/* Don't bother with non-allocated sections */
 			if (!(sechdrs[info].sh_flags & SHF_ALLOC))
 				continue;

 			if (sechdrs[i].sh_type == SHT_REL)
 				err = apply_relocations(sechdrs, strtab, symindex, i,
 							&mod);
 			else if (sechdrs[i].sh_type == SHT_RELA)
 				err = apply_relocate_add(sechdrs, strtab, symindex, i,
 							 &mod);
 			if (err < 0)
 				return err;

  		}
  	} else {
		struct elf_phdr *phdr = (struct elf_phdr *) ((char *)hdr + hdr->e_phoff);

		for (i = 0; i < hdr->e_phnum; i++) {
			if (phdr->p_type == PT_LOAD) {
				memcpy((void *)phdr->p_paddr,
				       (char *)hdr + phdr->p_offset,
				       phdr->p_filesz);
				memset((void *)phdr->p_paddr + phdr->p_filesz,
				       0, phdr->p_memsz - phdr->p_filesz);
		    }
		    phdr++;
		}

		for (i = 0; i < hdr->e_shnum; i++) {
 			/* Internal symbols and strings. */
 			if (sechdrs[i].sh_type == SHT_SYMTAB) {
 				symindex = i;
 				strindex = sechdrs[i].sh_link;
 				strtab = (char *)hdr + sechdrs[strindex].sh_offset;

 				/* mark the symtab's address for when we try to find the
 				   magic symbols */
 				sechdrs[i].sh_addr = (size_t) hdr + sechdrs[i].sh_offset;
 			}
		}
	}

	/* make sure it's physically written out */
	flush_icache_range((unsigned long)v->load_addr,
			   (unsigned long)v->load_addr + v->len);

	if ((find_vpe_symbols(v, sechdrs, symindex, strtab, &mod)) < 0) {
		if (v->__start == 0) {
			printk(KERN_WARNING "VPE loader: program does not contain "
			       "a __start symbol\n");
			return -ENOEXEC;
		}

		if (v->shared_ptr == NULL)
			printk(KERN_WARNING "VPE loader: "
			       "program does not contain vpe_shared symbol.\n"
			       " Unable to use AMVP (AP/SP) facilities.\n");
	}

	printk(" elf loaded\n");
	return 0;
}

static void cleanup_tc(struct tc *tc)
{
	unsigned long flags;
	unsigned int mtflags, vpflags;
	int tmp;

	local_irq_save(flags);
	mtflags = dmt();
	vpflags = dvpe();
	/* Put MVPE's into 'configuration state' */
	set_c0_mvpcontrol(MVPCONTROL_VPC);

	settc(tc->index);
	tmp = read_tc_c0_tcstatus();

	/* mark not allocated and not dynamically allocatable */
	tmp &= ~(TCSTATUS_A | TCSTATUS_DA);
	tmp |= TCSTATUS_IXMT;	/* interrupt exempt */
	write_tc_c0_tcstatus(tmp);

	write_tc_c0_tchalt(TCHALT_H);
	mips_ihb();

	/* bind it to anything other than VPE1 */
//	write_tc_c0_tcbind(read_tc_c0_tcbind() & ~TCBIND_CURVPE); // | TCBIND_CURVPE

	clear_c0_mvpcontrol(MVPCONTROL_VPC);
	evpe(vpflags);
	emt(mtflags);
	local_irq_restore(flags);
}

static int getcwd(char *buff, int size)
{
	mm_segment_t old_fs;
	int ret;

	old_fs = get_fs();
	set_fs(KERNEL_DS);

	ret = sys_getcwd(buff, size);

	set_fs(old_fs);

	return ret;
}

/* checks VPE is unused and gets ready to load program  */
static int vpe_open(struct inode *inode, struct file *filp)
{
	enum vpe_state state;
	struct vpe_notifications *not;
	struct vpe *v;
	int ret;

	if (minor != iminor(inode)) {
		/* assume only 1 device at the moment. */
		pr_warning("VPE loader: only vpe1 is supported\n");

		return -ENODEV;
	}

	if ((v = get_vpe(tclimit)) == NULL) {
		pr_warning("VPE loader: unable to get vpe\n");

		return -ENODEV;
	}

	state = xchg(&v->state, VPE_STATE_INUSE);
	if (state != VPE_STATE_UNUSED) {
		printk(KERN_DEBUG "VPE loader: tc in use dumping regs\n");

		list_for_each_entry(not, &v->notify, list) {
			not->stop(tclimit);
		}

		release_progmem(v->load_addr);
		cleanup_tc(get_tc(tclimit));
	}

	/* this of-course trashes what was there before... */
	v->pbuffer = vmalloc(P_SIZE);
	if (!v->pbuffer) {
		pr_warning("VPE loader: unable to allocate memory\n");
		return -ENOMEM;
	}
	v->plen = P_SIZE;
	v->load_addr = NULL;
	v->len = 0;

	v->uid = filp->f_cred->fsuid;
	v->gid = filp->f_cred->fsgid;

#ifdef CONFIG_MIPS_APSP_KSPD
	/* get kspd to tell us when a syscall_exit happens */
	if (!kspd_events_reqd) {
		kspd_notify(&kspd_events);
		kspd_events_reqd++;
	}
#endif

	v->cwd[0] = 0;
	ret = getcwd(v->cwd, VPE_PATH_MAX);
	if (ret < 0)
		printk(KERN_WARNING "VPE loader: open, getcwd returned %d\n", ret);

	v->shared_ptr = NULL;
	v->__start = 0;

	return 0;
}

static int vpe_release(struct inode *inode, struct file *filp)
{
	struct vpe *v;
	Elf_Ehdr *hdr;
	int ret = 0;

	v = get_vpe(tclimit);
	if (v == NULL)
		return -ENODEV;

	hdr = (Elf_Ehdr *) v->pbuffer;
	if (memcmp(hdr->e_ident, ELFMAG, SELFMAG) == 0) {
		if (vpe_elfload(v) >= 0) {
			vpe_run(v);
		} else {
 			printk(KERN_WARNING "VPE loader: ELF load failed.\n");
			ret = -ENOEXEC;
		}
	} else {
 		printk(KERN_WARNING "VPE loader: only elf files are supported\n");
		ret = -ENOEXEC;
	}

	/* It's good to be able to run the SP and if it chokes have a look at
	   the /dev/rt?. But if we reset the pointer to the shared struct we
	   lose what has happened. So perhaps if garbage is sent to the vpe
	   device, use it as a trigger for the reset. Hopefully a nice
	   executable will be along shortly. */
	if (ret < 0)
		v->shared_ptr = NULL;

	vfree(v->pbuffer);
	v->plen = 0;

	return ret;
}

static ssize_t vpe_write(struct file *file, const char __user * buffer,
			 size_t count, loff_t * ppos)
{
	size_t ret = count;
	struct vpe *v;

	if (iminor(file->f_path.dentry->d_inode) != minor)
		return -ENODEV;

	v = get_vpe(tclimit);
	if (v == NULL)
		return -ENODEV;

	if ((count + v->len) > v->plen) {
		printk(KERN_WARNING
		       "VPE loader: elf size too big. Perhaps strip uneeded symbols\n");
		return -ENOMEM;
	}

	count -= copy_from_user(v->pbuffer + v->len, buffer, count);
	if (!count)
		return -EFAULT;

	v->len += count;
	return ret;
}

static const struct file_operations vpe_fops = {
	.owner = THIS_MODULE,
	.open = vpe_open,
	.release = vpe_release,
	.write = vpe_write,
	.llseek = noop_llseek,
};

/* module wrapper entry points */
/* give me a vpe */
vpe_handle vpe_alloc(void)
{
	int i;
	struct vpe *v;

	/* find a vpe */
	for (i = 1; i < MAX_VPES; i++) {
		if ((v = get_vpe(i)) != NULL) {
			v->state = VPE_STATE_INUSE;
			return v;
		}
	}
	return NULL;
}

EXPORT_SYMBOL(vpe_alloc);

/* start running from here */
int vpe_start(vpe_handle vpe, unsigned long start)
{
	struct vpe *v = vpe;

	v->__start = start;
	return vpe_run(v);
}

EXPORT_SYMBOL(vpe_start);

/* halt it for now */
int vpe_stop(vpe_handle vpe)
{
	struct vpe *v = vpe;
	struct tc *t;
	unsigned int evpe_flags;

	evpe_flags = dvpe();

	if ((t = list_entry(v->tc.next, struct tc, tc)) != NULL) {

		settc(t->index);
		write_vpe_c0_vpeconf0(read_vpe_c0_vpeconf0() & ~VPECONF0_VPA);
	}

	evpe(evpe_flags);

	return 0;
}

EXPORT_SYMBOL(vpe_stop);

/* I've done with it thank you */
int vpe_free(vpe_handle vpe)
{
	struct vpe *v = vpe;
	struct tc *t;
	unsigned int evpe_flags;

	if ((t = list_entry(v->tc.next, struct tc, tc)) == NULL) {
		return -ENOEXEC;
	}

	evpe_flags = dvpe();

	/* Put MVPE's into 'configuration state' */
	set_c0_mvpcontrol(MVPCONTROL_VPC);

	settc(t->index);
	write_vpe_c0_vpeconf0(read_vpe_c0_vpeconf0() & ~VPECONF0_VPA);

	/* halt the TC */
	write_tc_c0_tchalt(TCHALT_H);
	mips_ihb();

	/* mark the TC unallocated */
	write_tc_c0_tcstatus(read_tc_c0_tcstatus() & ~TCSTATUS_A);

	v->state = VPE_STATE_UNUSED;

	clear_c0_mvpcontrol(MVPCONTROL_VPC);
	evpe(evpe_flags);

	return 0;
}

EXPORT_SYMBOL(vpe_free);

void *vpe_get_shared(int index)
{
	struct vpe *v;

	if ((v = get_vpe(index)) == NULL)
		return NULL;

	return v->shared_ptr;
}

EXPORT_SYMBOL(vpe_get_shared);

int vpe_getuid(int index)
{
	struct vpe *v;

	if ((v = get_vpe(index)) == NULL)
		return -1;

	return v->uid;
}

EXPORT_SYMBOL(vpe_getuid);

int vpe_getgid(int index)
{
	struct vpe *v;

	if ((v = get_vpe(index)) == NULL)
		return -1;

	return v->gid;
}

EXPORT_SYMBOL(vpe_getgid);

int vpe_notify(int index, struct vpe_notifications *notify)
{
	struct vpe *v;

	if ((v = get_vpe(index)) == NULL)
		return -1;

	list_add(&notify->list, &v->notify);
	return 0;
}

EXPORT_SYMBOL(vpe_notify);

char *vpe_getcwd(int index)
{
	struct vpe *v;

	if ((v = get_vpe(index)) == NULL)
		return NULL;

	return v->cwd;
}

EXPORT_SYMBOL(vpe_getcwd);

#ifdef CONFIG_MIPS_APSP_KSPD
static void kspd_sp_exit( int sp_id)
{
	cleanup_tc(get_tc(sp_id));
}
#endif

static ssize_t store_kill(struct device *dev, struct device_attribute *attr,
			  const char *buf, size_t len)
{
	struct vpe *vpe = get_vpe(tclimit);
	struct vpe_notifications *not;

	list_for_each_entry(not, &vpe->notify, list) {
		not->stop(tclimit);
	}

	release_progmem(vpe->load_addr);
	cleanup_tc(get_tc(tclimit));
	vpe_stop(vpe);
	vpe_free(vpe);

	return len;
}

static ssize_t show_ntcs(struct device *cd, struct device_attribute *attr,
			 char *buf)
{
	struct vpe *vpe = get_vpe(tclimit);

	return sprintf(buf, "%d\n", vpe->ntcs);
}

static ssize_t store_ntcs(struct device *dev, struct device_attribute *attr,
			  const char *buf, size_t len)
{
	struct vpe *vpe = get_vpe(tclimit);
	unsigned long new;
	char *endp;

	new = simple_strtoul(buf, &endp, 0);
	if (endp == buf)
		goto out_einval;

	if (new == 0 || new > (hw_tcs - tclimit))
		goto out_einval;

	vpe->ntcs = new;

	return len;

out_einval:
	return -EINVAL;
}

static struct device_attribute vpe_class_attributes[] = {
	__ATTR(kill, S_IWUSR, NULL, store_kill),
	__ATTR(ntcs, S_IRUGO | S_IWUSR, show_ntcs, store_ntcs),
	{}
};

static void vpe_device_release(struct device *cd)
{
	kfree(cd);
}

struct class vpe_class = {
	.name = "vpe",
	.owner = THIS_MODULE,
	.dev_release = vpe_device_release,
	.dev_attrs = vpe_class_attributes,
};

struct device vpe_device;

static int __init vpe_module_init(void)
{
	unsigned int mtflags, vpflags;
	unsigned long flags, val;
	struct vpe *v = NULL;
	struct tc *t;
	int tc, err;

	if (!cpu_has_mipsmt) {
		printk("VPE loader: not a MIPS MT capable processor\n");
		return -ENODEV;
	}

	if (vpelimit == 0) {
		printk(KERN_WARNING "No VPEs reserved for AP/SP, not "
		       "initializing VPE loader.\nPass maxvpes=<n> argument as "
		       "kernel argument\n");

		return -ENODEV;
	}

	if (tclimit == 0) {
		printk(KERN_WARNING "No TCs reserved for AP/SP, not "
		       "initializing VPE loader.\nPass maxtcs=<n> argument as "
		       "kernel argument\n");

		return -ENODEV;
	}

	major = register_chrdev(0, module_name, &vpe_fops);
	if (major < 0) {
		printk("VPE loader: unable to register character device\n");
		return major;
	}

	err = class_register(&vpe_class);
	if (err) {
		printk(KERN_ERR "vpe_class registration failed\n");
		goto out_chrdev;
	}

	device_initialize(&vpe_device);
	vpe_device.class	= &vpe_class,
	vpe_device.parent	= NULL,
	dev_set_name(&vpe_device, "vpe1");
	vpe_device.devt = MKDEV(major, minor);
	err = device_add(&vpe_device);
	if (err) {
		printk(KERN_ERR "Adding vpe_device failed\n");
		goto out_class;
	}

	local_irq_save(flags);
	mtflags = dmt();
	vpflags = dvpe();

	/* Put MVPE's into 'configuration state' */
	set_c0_mvpcontrol(MVPCONTROL_VPC);

	/* dump_mtregs(); */

	val = read_c0_mvpconf0();
	hw_tcs = (val & MVPCONF0_PTC) + 1;
	hw_vpes = ((val & MVPCONF0_PVPE) >> MVPCONF0_PVPE_SHIFT) + 1;

	for (tc = tclimit; tc < hw_tcs; tc++) {
		/*
		 * Must re-enable multithreading temporarily or in case we
		 * reschedule send IPIs or similar we might hang.
		 */
		clear_c0_mvpcontrol(MVPCONTROL_VPC);
		evpe(vpflags);
		emt(mtflags);
		local_irq_restore(flags);
		t = alloc_tc(tc);
		if (!t) {
			err = -ENOMEM;
			goto out;
		}

		local_irq_save(flags);
		mtflags = dmt();
		vpflags = dvpe();
		set_c0_mvpcontrol(MVPCONTROL_VPC);

		/* VPE's */
		if (tc < hw_tcs) {
			settc(tc);

			if ((v = alloc_vpe(tc)) == NULL) {
				printk(KERN_WARNING "VPE: unable to allocate VPE\n");

				goto out_reenable;
			}

			v->ntcs = hw_tcs - tclimit;

			/* add the tc to the list of this vpe's tc's. */
			list_add(&t->tc, &v->tc);

			/* deactivate all but vpe0 */
			if (tc >= tclimit) {
				unsigned long tmp = read_vpe_c0_vpeconf0();

				tmp &= ~VPECONF0_VPA;

				/* master VPE */
				tmp |= VPECONF0_MVP;
				write_vpe_c0_vpeconf0(tmp);
			}

			/* disable multi-threading with TC's */
			write_vpe_c0_vpecontrol(read_vpe_c0_vpecontrol() & ~VPECONTROL_TE);

			if (tc >= vpelimit) {
				/*
				 * Set config to be the same as vpe0,
				 * particularly kseg0 coherency alg
				 */
				write_vpe_c0_config(read_c0_config());
			}
		}

		/* TC's */
		t->pvpe = v;	/* set the parent vpe */

		if (tc >= tclimit) {
			unsigned long tmp;

			settc(tc);

			/* Any TC that is bound to VPE0 gets left as is - in case
			   we are running SMTC on VPE0. A TC that is bound to any
			   other VPE gets bound to VPE0, ideally I'd like to make
			   it homeless but it doesn't appear to let me bind a TC
			   to a non-existent VPE. Which is perfectly reasonable.

			   The (un)bound state is visible to an EJTAG probe so may
			   notify GDB...
			*/

			if (((tmp = read_tc_c0_tcbind()) & TCBIND_CURVPE)) {
				/* tc is bound >vpe0 */
				write_tc_c0_tcbind(tmp & ~TCBIND_CURVPE);

				t->pvpe = get_vpe(0);	/* set the parent vpe */
			}

			/* halt the TC */
			write_tc_c0_tchalt(TCHALT_H);
			mips_ihb();

			tmp = read_tc_c0_tcstatus();

			/* mark not activated and not dynamically allocatable */
			tmp &= ~(TCSTATUS_A | TCSTATUS_DA);
			tmp |= TCSTATUS_IXMT;	/* interrupt exempt */
			write_tc_c0_tcstatus(tmp);
		}
	}

out_reenable:
	/* release config state */
	clear_c0_mvpcontrol(MVPCONTROL_VPC);

	evpe(vpflags);
	emt(mtflags);
	local_irq_restore(flags);

#ifdef CONFIG_MIPS_APSP_KSPD
	kspd_events.kspd_sp_exit = kspd_sp_exit;
#endif
	return 0;

out_class:
	class_unregister(&vpe_class);
out_chrdev:
	unregister_chrdev(major, module_name);

out:
	return err;
}

static void __exit vpe_module_exit(void)
{
	struct vpe *v, *n;

	device_del(&vpe_device);
	unregister_chrdev(major, module_name);

	/* No locking needed here */
	list_for_each_entry_safe(v, n, &vpecontrol.vpe_list, list) {
		if (v->state != VPE_STATE_UNUSED)
			release_vpe(v);
	}
}

module_init(vpe_module_init);
module_exit(vpe_module_exit);
MODULE_DESCRIPTION("MIPS VPE Loader");
MODULE_AUTHOR("Elizabeth Oldham, MIPS Technologies, Inc.");
MODULE_LICENSE("GPL");

Privacy Policy