aboutsummaryrefslogtreecommitdiffstats
path: root/drivers/platform/x86/intel_ips.c
blob: 0ffdb3cde2bbc3ff569fee774dcd842333585031 (plain) (blame)
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
/*
 * Copyright (c) 2009-2010 Intel Corporation
 *
 * This program is free software; you can redistribute it and/or modify it
 * under the terms and conditions 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.,
 * 51 Franklin St - Fifth Floor, Boston, MA 02110-1301 USA.
 *
 * The full GNU General Public License is included in this distribution in
 * the file called "COPYING".
 *
 * Authors:
 *	Jesse Barnes <jbarnes@virtuousgeek.org>
 */

/*
 * Some Intel Ibex Peak based platforms support so-called "intelligent
 * power sharing", which allows the CPU and GPU to cooperate to maximize
 * performance within a given TDP (thermal design point).  This driver
 * performs the coordination between the CPU and GPU, monitors thermal and
 * power statistics in the platform, and initializes power monitoring
 * hardware.  It also provides a few tunables to control behavior.  Its
 * primary purpose is to safely allow CPU and GPU turbo modes to be enabled
 * by tracking power and thermal budget; secondarily it can boost turbo
 * performance by allocating more power or thermal budget to the CPU or GPU
 * based on available headroom and activity.
 *
 * The basic algorithm is driven by a 5s moving average of tempurature.  If
 * thermal headroom is available, the CPU and/or GPU power clamps may be
 * adjusted upwards.  If we hit the thermal ceiling or a thermal trigger,
 * we scale back the clamp.  Aside from trigger events (when we're critically
 * close or over our TDP) we don't adjust the clamps more than once every
 * five seconds.
 *
 * The thermal device (device 31, function 6) has a set of registers that
 * are updated by the ME firmware.  The ME should also take the clamp values
 * written to those registers and write them to the CPU, but we currently
 * bypass that functionality and write the CPU MSR directly.
 *
 * UNSUPPORTED:
 *   - dual MCP configs
 *
 * TODO:
 *   - handle CPU hotplug
 *   - provide turbo enable/disable api
 *
 * Related documents:
 *   - CDI 403777, 403778 - Auburndale EDS vol 1 & 2
 *   - CDI 401376 - Ibex Peak EDS
 *   - ref 26037, 26641 - IPS BIOS spec
 *   - ref 26489 - Nehalem BIOS writer's guide
 *   - ref 26921 - Ibex Peak BIOS Specification
 */

#include <linux/debugfs.h>
#include <linux/delay.h>
#include <linux/interrupt.h>
#include <linux/kernel.h>
#include <linux/kthread.h>
#include <linux/module.h>
#include <linux/pci.h>
#include <linux/sched.h>
#include <linux/seq_file.h>
#include <linux/string.h>
#include <linux/tick.h>
#include <linux/timer.h>
#include <drm/i915_drm.h>
#include <asm/msr.h>
#include <asm/processor.h>
#include "intel_ips.h"

#include <asm-generic/io-64-nonatomic-lo-hi.h>

#define PCI_DEVICE_ID_INTEL_THERMAL_SENSOR 0x3b32

/*
 * Package level MSRs for monitor/control
 */
#define PLATFORM_INFO	0xce
#define   PLATFORM_TDP		(1<<29)
#define   PLATFORM_RATIO	(1<<28)

#define IA32_MISC_ENABLE	0x1a0
#define   IA32_MISC_TURBO_EN	(1ULL<<38)

#define TURBO_POWER_CURRENT_LIMIT	0x1ac
#define   TURBO_TDC_OVR_EN	(1UL<<31)
#define   TURBO_TDC_MASK	(0x000000007fff0000UL)
#define   TURBO_TDC_SHIFT	(16)
#define   TURBO_TDP_OVR_EN	(1UL<<15)
#define   TURBO_TDP_MASK	(0x0000000000003fffUL)

/*
 * Core/thread MSRs for monitoring
 */
#define IA32_PERF_CTL		0x199
#define   IA32_PERF_TURBO_DIS	(1ULL<<32)

/*
 * Thermal PCI device regs
 */
#define THM_CFG_TBAR	0x10
#define THM_CFG_TBAR_HI	0x14

#define THM_TSIU	0x00
#define THM_TSE		0x01
#define   TSE_EN	0xb8
#define THM_TSS		0x02
#define THM_TSTR	0x03
#define THM_TSTTP	0x04
#define THM_TSCO	0x08
#define THM_TSES	0x0c
#define THM_TSGPEN	0x0d
#define   TSGPEN_HOT_LOHI	(1<<1)
#define   TSGPEN_CRIT_LOHI	(1<<2)
#define THM_TSPC	0x0e
#define THM_PPEC	0x10
#define THM_CTA		0x12
#define THM_PTA		0x14
#define   PTA_SLOPE_MASK	(0xff00)
#define   PTA_SLOPE_SHIFT	8
#define   PTA_OFFSET_MASK	(0x00ff)
#define THM_MGTA	0x16
#define   MGTA_SLOPE_MASK	(0xff00)
#define   MGTA_SLOPE_SHIFT	8
#define   MGTA_OFFSET_MASK	(0x00ff)
#define THM_TRC		0x1a
#define   TRC_CORE2_EN	(1<<15)
#define   TRC_THM_EN	(1<<12)
#define   TRC_C6_WAR	(1<<8)
#define   TRC_CORE1_EN	(1<<7)
#define   TRC_CORE_PWR	(1<<6)
#define   TRC_PCH_EN	(1<<5)
#define   TRC_MCH_EN	(1<<4)
#define   TRC_DIMM4	(1<<3)
#define   TRC_DIMM3	(1<<2)
#define   TRC_DIMM2	(1<<1)
#define   TRC_DIMM1	(1<<0)
#define THM_TES		0x20
#define THM_TEN		0x21
#define   TEN_UPDATE_EN	1
#define THM_PSC		0x24
#define   PSC_NTG	(1<<0) /* No GFX turbo support */
#define   PSC_NTPC	(1<<1) /* No CPU turbo support */
#define   PSC_PP_DEF	(0<<2) /* Perf policy up to driver */
#define   PSP_PP_PC	(1<<2) /* BIOS prefers CPU perf */
#define   PSP_PP_BAL	(2<<2) /* BIOS wants balanced perf */
#define   PSP_PP_GFX	(3<<2) /* BIOS prefers GFX perf */
#define   PSP_PBRT	(1<<4) /* BIOS run time support */
#define THM_CTV1	0x30
#define   CTV_TEMP_ERROR (1<<15)
#define   CTV_TEMP_MASK	0x3f
#define   CTV_
#define THM_CTV2	0x32
#define THM_CEC		0x34 /* undocumented power accumulator in joules */
#define THM_AE		0x3f
#define THM_HTS		0x50 /* 32 bits */
#define   HTS_PCPL_MASK	(0x7fe00000)
#define   HTS_PCPL_SHIFT 21
#define   HTS_GPL_MASK  (0x001ff000)
#define   HTS_GPL_SHIFT 12
#define   HTS_PP_MASK	(0x00000c00)
#define   HTS_PP_SHIFT  10
#define   HTS_PP_DEF	0
#define   HTS_PP_PROC	1
#define   HTS_PP_BAL	2
#define   HTS_PP_GFX	3
#define   HTS_PCTD_DIS	(1<<9)
#define   HTS_GTD_DIS	(1<<8)
#define   HTS_PTL_MASK  (0x000000fe)
#define   HTS_PTL_SHIFT 1
#define   HTS_NVV	(1<<0)
#define THM_HTSHI	0x54 /* 16 bits */
#define   HTS2_PPL_MASK		(0x03ff)
#define   HTS2_PRST_MASK	(0x3c00)
#define   HTS2_PRST_SHIFT	10
#define   HTS2_PRST_UNLOADED	0
#define   HTS2_PRST_RUNNING	1
#define   HTS2_PRST_TDISOP	2 /* turbo disabled due to power */
#define   HTS2_PRST_TDISHT	3 /* turbo disabled due to high temp */
#define   HTS2_PRST_TDISUSR	4 /* user disabled turbo */
#define   HTS2_PRST_TDISPLAT	5 /* platform disabled turbo */
#define   HTS2_PRST_TDISPM	6 /* power management disabled turbo */
#define   HTS2_PRST_TDISERR	7 /* some kind of error disabled turbo */
#define THM_PTL		0x56
#define THM_MGTV	0x58
#define   TV_MASK	0x000000000000ff00
#define   TV_SHIFT	8
#define THM_PTV		0x60
#define   PTV_MASK	0x00ff
#define THM_MMGPC	0x64
#define THM_MPPC	0x66
#define THM_MPCPC	0x68
#define THM_TSPIEN	0x82
#define   TSPIEN_AUX_LOHI	(1<<0)
#define   TSPIEN_HOT_LOHI	(1<<1)
#define   TSPIEN_CRIT_LOHI	(1<<2)
#define   TSPIEN_AUX2_LOHI	(1<<3)
#define THM_TSLOCK	0x83
#define THM_ATR		0x84
#define THM_TOF		0x87
#define THM_STS		0x98
#define   STS_PCPL_MASK		(0x7fe00000)
#define   STS_PCPL_SHIFT	21
#define   STS_GPL_MASK		(0x001ff000)
#define   STS_GPL_SHIFT		12
#define   STS_PP_MASK		(0x00000c00)
#define   STS_PP_SHIFT		10
#define   STS_PP_DEF		0
#define   STS_PP_PROC		1
#define   STS_PP_BAL		2
#define   STS_PP_GFX		3
#define   STS_PCTD_DIS		(1<<9)
#define   STS_GTD_DIS		(1<<8)
#define   STS_PTL_MASK		(0x000000fe)
#define   STS_PTL_SHIFT		1
#define   STS_NVV		(1<<0)
#define THM_SEC		0x9c
#define   SEC_ACK	(1<<0)
#define THM_TC3		0xa4
#define THM_TC1		0xa8
#define   STS_PPL_MASK		(0x0003ff00)
#define   STS_PPL_SHIFT		16
#define THM_TC2		0xac
#define THM_DTV		0xb0
#define THM_ITV		0xd8
#define   ITV_ME_SEQNO_MASK 0x00ff0000 /* ME should update every ~200ms */
#define   ITV_ME_SEQNO_SHIFT (16)
#define   ITV_MCH_TEMP_MASK 0x0000ff00
#define   ITV_MCH_TEMP_SHIFT (8)
#define   ITV_PCH_TEMP_MASK 0x000000ff

#define thm_readb(off) readb(ips->regmap + (off))
#define thm_readw(off) readw(ips->regmap + (off))
#define thm_readl(off) readl(ips->regmap + (off))
#define thm_readq(off) readq(ips->regmap + (off))

#define thm_writeb(off, val) writeb((val), ips->regmap + (off))
#define thm_writew(off, val) writew((val), ips->regmap + (off))
#define thm_writel(off, val) writel((val), ips->regmap + (off))

static const int IPS_ADJUST_PERIOD = 5000; /* ms */
static bool late_i915_load = false;

/* For initial average collection */
static const int IPS_SAMPLE_PERIOD = 200; /* ms */
static const int IPS_SAMPLE_WINDOW = 5000; /* 5s moving window of samples */
#define IPS_SAMPLE_COUNT (IPS_SAMPLE_WINDOW / IPS_SAMPLE_PERIOD)

/* Per-SKU limits */
struct ips_mcp_limits {
	int cpu_family;
	int cpu_model; /* includes extended model... */
	int mcp_power_limit; /* mW units */
	int core_power_limit;
	int mch_power_limit;
	int core_temp_limit; /* degrees C */
	int mch_temp_limit;
};

/* Max temps are -10 degrees C to avoid PROCHOT# */

struct ips_mcp_limits ips_sv_limits = {
	.mcp_power_limit = 35000,
	.core_power_limit = 29000,
	.mch_power_limit = 20000,
	.core_temp_limit = 95,
	.mch_temp_limit = 90
};

struct ips_mcp_limits ips_lv_limits = {
	.mcp_power_limit = 25000,
	.core_power_limit = 21000,
	.mch_power_limit = 13000,
	.core_temp_limit = 95,
	.mch_temp_limit = 90
};

struct ips_mcp_limits ips_ulv_limits = {
	.mcp_power_limit = 18000,
	.core_power_limit = 14000,
	.mch_power_limit = 11000,
	.core_temp_limit = 95,
	.mch_temp_limit = 90
};

struct ips_driver {
	struct pci_dev *dev;
	void *regmap;
	struct task_struct *monitor;
	struct task_struct *adjust;
	struct dentry *debug_root;

	/* Average CPU core temps (all averages in .01 degrees C for precision) */
	u16 ctv1_avg_temp;
	u16 ctv2_avg_temp;
	/* GMCH average */
	u16 mch_avg_temp;
	/* Average for the CPU (both cores?) */
	u16 mcp_avg_temp;
	/* Average power consumption (in mW) */
	u32 cpu_avg_power;
	u32 mch_avg_power;

	/* Offset values */
	u16 cta_val;
	u16 pta_val;
	u16 mgta_val;

	/* Maximums & prefs, protected by turbo status lock */
	spinlock_t turbo_status_lock;
	u16 mcp_temp_limit;
	u16 mcp_power_limit;
	u16 core_power_limit;
	u16 mch_power_limit;
	bool cpu_turbo_enabled;
	bool __cpu_turbo_on;
	bool gpu_turbo_enabled;
	bool __gpu_turbo_on;
	bool gpu_preferred;
	bool poll_turbo_status;
	bool second_cpu;
	bool turbo_toggle_allowed;
	struct ips_mcp_limits *limits;

	/* Optional MCH interfaces for if i915 is in use */
	unsigned long (*read_mch_val)(void);
	bool (*gpu_raise)(void);
	bool (*gpu_lower)(void);
	bool (*gpu_busy)(void);
	bool (*gpu_turbo_disable)(void);

	/* For restoration at unload */
	u64 orig_turbo_limit;
	u64 orig_turbo_ratios;
};

static bool
ips_gpu_turbo_enabled(struct ips_driver *ips);

/**
 * ips_cpu_busy - is CPU busy?
 * @ips: IPS driver struct
 *
 * Check CPU for load to see whether we should increase its thermal budget.
 *
 * RETURNS:
 * True if the CPU could use more power, false otherwise.
 */
static bool ips_cpu_busy(struct ips_driver *ips)
{
	if ((avenrun[0] >> FSHIFT) > 1)
		return true;

	return false;
}

/**
 * ips_cpu_raise - raise CPU power clamp
 * @ips: IPS driver struct
 *
 * Raise the CPU power clamp by %IPS_CPU_STEP, in accordance with TDP for
 * this platform.
 *
 * We do this by adjusting the TURBO_POWER_CURRENT_LIMIT MSR upwards (as
 * long as we haven't hit the TDP limit for the SKU).
 */
static void ips_cpu_raise(struct ips_driver *ips)
{
	u64 turbo_override;
	u16 cur_tdp_limit, new_tdp_limit;

	if (!ips->cpu_turbo_enabled)
		return;

	rdmsrl(TURBO_POWER_CURRENT_LIMIT, turbo_override);

	cur_tdp_limit = turbo_override & TURBO_TDP_MASK;
	new_tdp_limit = cur_tdp_limit + 8; /* 1W increase */

	/* Clamp to SKU TDP limit */
	if (((new_tdp_limit * 10) / 8) > ips->core_power_limit)
		new_tdp_limit = cur_tdp_limit;

	thm_writew(THM_MPCPC, (new_tdp_limit * 10) / 8);

	turbo_override |= TURBO_TDC_OVR_EN | TURBO_TDP_OVR_EN;
	wrmsrl(TURBO_POWER_CURRENT_LIMIT, turbo_override);

	turbo_override &= ~TURBO_TDP_MASK;
	turbo_override |= new_tdp_limit;

	wrmsrl(TURBO_POWER_CURRENT_LIMIT, turbo_override);
}

/**
 * ips_cpu_lower - lower CPU power clamp
 * @ips: IPS driver struct
 *
 * Lower CPU power clamp b %IPS_CPU_STEP if possible.
 *
 * We do this by adjusting the TURBO_POWER_CURRENT_LIMIT MSR down, going
 * as low as the platform limits will allow (though we could go lower there
 * wouldn't be much point).
 */
static void ips_cpu_lower(struct ips_driver *ips)
{
	u64 turbo_override;
	u16 cur_limit, new_limit;

	rdmsrl(TURBO_POWER_CURRENT_LIMIT, turbo_override);

	cur_limit = turbo_override & TURBO_TDP_MASK;
	new_limit = cur_limit - 8; /* 1W decrease */

	/* Clamp to SKU TDP limit */
	if (new_limit  < (ips->orig_turbo_limit & TURBO_TDP_MASK))
		new_limit = ips->orig_turbo_limit & TURBO_TDP_MASK;

	thm_writew(THM_MPCPC, (new_limit * 10) / 8);

	turbo_override |= TURBO_TDC_OVR_EN | TURBO_TDP_OVR_EN;
	wrmsrl(TURBO_POWER_CURRENT_LIMIT, turbo_override);

	turbo_override &= ~TURBO_TDP_MASK;
	turbo_override |= new_limit;

	wrmsrl(TURBO_POWER_CURRENT_LIMIT, turbo_override);
}

/**
 * do_enable_cpu_turbo - internal turbo enable function
 * @data: unused
 *
 * Internal function for actually updating MSRs.  When we enable/disable
 * turbo, we need to do it on each CPU; this function is the one called
 * by on_each_cpu() when needed.
 */
static void do_enable_cpu_turbo(void *data)
{
	u64 perf_ctl;

	rdmsrl(IA32_PERF_CTL, perf_ctl);
	if (perf_ctl & IA32_PERF_TURBO_DIS) {
		perf_ctl &= ~IA32_PERF_TURBO_DIS;
		wrmsrl(IA32_PERF_CTL, perf_ctl);
	}
}

/**
 * ips_enable_cpu_turbo - enable turbo mode on all CPUs
 * @ips: IPS driver struct
 *
 * Enable turbo mode by clearing the disable bit in IA32_PERF_CTL on
 * all logical threads.
 */
static void ips_enable_cpu_turbo(struct ips_driver *ips)
{
	/* Already on, no need to mess with MSRs */
	if (ips->__cpu_turbo_on)
		return;

	if (ips->turbo_toggle_allowed)
		on_each_cpu(do_enable_cpu_turbo, ips, 1);

	ips->__cpu_turbo_on = true;
}

/**
 * do_disable_cpu_turbo - internal turbo disable function
 * @data: unused
 *
 * Internal function for actually updating MSRs.  When we enable/disable
 * turbo, we need to do it on each CPU; this function is the one called
 * by on_each_cpu() when needed.
 */
static void do_disable_cpu_turbo(void *data)
{
	u64 perf_ctl;

	rdmsrl(IA32_PERF_CTL, perf_ctl);
	if (!(perf_ctl & IA32_PERF_TURBO_DIS)) {
		perf_ctl |= IA32_PERF_TURBO_DIS;
		wrmsrl(IA32_PERF_CTL, perf_ctl);
	}
}

/**
 * ips_disable_cpu_turbo - disable turbo mode on all CPUs
 * @ips: IPS driver struct
 *
 * Disable turbo mode by setting the disable bit in IA32_PERF_CTL on
 * all logical threads.
 */
static void ips_disable_cpu_turbo(struct ips_driver *ips)
{
	/* Already off, leave it */
	if (!ips->__cpu_turbo_on)
		return;

	if (ips->turbo_toggle_allowed)
		on_each_cpu(do_disable_cpu_turbo, ips, 1);

	ips->__cpu_turbo_on = false;
}

/**
 * ips_gpu_busy - is GPU busy?
 * @ips: IPS driver struct
 *
 * Check GPU for load to see whether we should increase its thermal budget.
 * We need to call into the i915 driver in this case.
 *
 * RETURNS:
 * True if the GPU could use more power, false otherwise.
 */
static bool ips_gpu_busy(struct ips_driver *ips)
{
	if (!ips_gpu_turbo_enabled(ips))
		return false;

	return ips->gpu_busy();
}

/**
 * ips_gpu_raise - raise GPU power clamp
 * @ips: IPS driver struct
 *
 * Raise the GPU frequency/power if possible.  We need to call into the
 * i915 driver in this case.
 */
static void ips_gpu_raise(struct ips_driver *ips)
{
	if (!ips_gpu_turbo_enabled(ips))
		return;

	if (!ips->gpu_raise())
		ips->gpu_turbo_enabled = false;

	return;
}

/**
 * ips_gpu_lower - lower GPU power clamp
 * @ips: IPS driver struct
 *
 * Lower GPU frequency/power if possible.  Need to call i915.
 */
static void ips_gpu_lower(struct ips_driver *ips)
{
	if (!ips_gpu_turbo_enabled(ips))
		return;

	if (!ips->gpu_lower())
		ips->gpu_turbo_enabled = false;

	return;
}

/**
 * ips_enable_gpu_turbo - notify the gfx driver turbo is available
 * @ips: IPS driver struct
 *
 * Call into the graphics driver indicating that it can safely use
 * turbo mode.
 */
static void ips_enable_gpu_turbo(struct ips_driver *ips)
{
	if (ips->__gpu_turbo_on)
		return;
	ips->__gpu_turbo_on = true;
}

/**
 * ips_disable_gpu_turbo - notify the gfx driver to disable turbo mode
 * @ips: IPS driver struct
 *
 * Request that the graphics driver disable turbo mode.
 */
static void ips_disable_gpu_turbo(struct ips_driver *ips)
{
	/* Avoid calling i915 if turbo is already disabled */
	if (!ips->__gpu_turbo_on)
		return;

	if (!ips->gpu_turbo_disable())
		dev_err(&ips->dev->dev, "failed to disable graphis turbo\n");
	else
		ips->__gpu_turbo_on = false;
}

/**
 * mcp_exceeded - check whether we're outside our thermal & power limits
 * @ips: IPS driver struct
 *
 * Check whether the MCP is over its thermal or power budget.
 */
static bool mcp_exceeded(struct ips_driver *ips)
{
	unsigned long flags;
	bool ret = false;
	u32 temp_limit;
	u32 avg_power;

	spin_lock_irqsave(&ips->turbo_status_lock, flags);

	temp_limit = ips->mcp_temp_limit * 100;
	if (ips->mcp_avg_temp > temp_limit)
		ret = true;

	avg_power = ips->cpu_avg_power + ips->mch_avg_power;
	if (avg_power > ips->mcp_power_limit)
		ret = true;

	spin_unlock_irqrestore(&ips->turbo_status_lock, flags);

	return ret;
}

/**
 * cpu_exceeded - check whether a CPU core is outside its limits
 * @ips: IPS driver struct
 * @cpu: CPU number to check
 *
 * Check a given CPU's average temp or power is over its limit.
 */
static bool cpu_exceeded(struct ips_driver *ips, int cpu)
{
	unsigned long flags;
	int avg;
	bool ret = false;

	spin_lock_irqsave(&ips->turbo_status_lock, flags);
	avg = cpu ? ips->ctv2_avg_temp : ips->ctv1_avg_temp;
	if (avg > (ips->limits->core_temp_limit * 100))
		ret = true;
	if (ips->cpu_avg_power > ips->core_power_limit * 100)
		ret = true;
	spin_unlock_irqrestore(&ips->turbo_status_lock, flags);

	if (ret)
		dev_info(&ips->dev->dev,
			 "CPU power or thermal limit exceeded\n");

	return ret;
}

/**
 * mch_exceeded - check whether the GPU is over budget
 * @ips: IPS driver struct
 *
 * Check the MCH temp & power against their maximums.
 */
static bool mch_exceeded(struct ips_driver *ips)
{
	unsigned long flags;
	bool ret = false;

	spin_lock_irqsave(&ips->turbo_status_lock, flags);
	if (ips->mch_avg_temp > (ips->limits->mch_temp_limit * 100))
		ret = true;
	if (ips->mch_avg_power > ips->mch_power_limit)
		ret = true;
	spin_unlock_irqrestore(&ips->turbo_status_lock, flags);

	return ret;
}

/**
 * verify_limits - verify BIOS provided limits
 * @ips: IPS structure
 *
 * BIOS can optionally provide non-default limits for power and temp.  Check
 * them here and use the defaults if the BIOS values are not provided or
 * are otherwise unusable.
 */
static void verify_limits(struct ips_driver *ips)
{
	if (ips->mcp_power_limit < ips->limits->mcp_power_limit ||
	    ips->mcp_power_limit > 35000)
		ips->mcp_power_limit = ips->limits->mcp_power_limit;

	if (ips->mcp_temp_limit < ips->limits->core_temp_limit ||
	    ips->mcp_temp_limit < ips->limits->mch_temp_limit ||
	    ips->mcp_temp_limit > 150)
		ips->mcp_temp_limit = min(ips->limits->core_temp_limit,
					  ips->limits->mch_temp_limit);
}

/**
 * update_turbo_limits - get various limits & settings from regs
 * @ips: IPS driver struct
 *
 * Update the IPS power & temp limits, along with turbo enable flags,
 * based on latest register contents.
 *
 * Used at init time and for runtime BIOS support, which requires polling
 * the regs for updates (as a result of AC->DC transition for example).
 *
 * LOCKING:
 * Caller must hold turbo_status_lock (outside of init)
 */
static void update_turbo_limits(struct ips_driver *ips)
{
	u32 hts = thm_readl(THM_HTS);

	ips->cpu_turbo_enabled = !(hts & HTS_PCTD_DIS);
	/* 
	 * Disable turbo for now, until we can figure out why the power figures
	 * are wrong
	 */
	ips->cpu_turbo_enabled = false;

	if (ips->gpu_busy)
		ips->gpu_turbo_enabled = !(hts & HTS_GTD_DIS);

	ips->core_power_limit = thm_readw(THM_MPCPC);
	ips->mch_power_limit = thm_readw(THM_MMGPC);
	ips->mcp_temp_limit = thm_readw(THM_PTL);
	ips->mcp_power_limit = thm_readw(THM_MPPC);

	verify_limits(ips);
	/* Ignore BIOS CPU vs GPU pref */
}

/**
 * ips_adjust - adjust power clamp based on thermal state
 * @data: ips driver structure
 *
 * Wake up every 5s or so and check whether we should adjust the power clamp.
 * Check CPU and GPU load to determine which needs adjustment.  There are
 * several things to consider here:
 *   - do we need to adjust up or down?
 *   - is CPU busy?
 *   - is GPU busy?
 *   - is CPU in turbo?
 *   - is GPU in turbo?
 *   - is CPU or GPU preferred? (CPU is default)
 *
 * So, given the above, we do the following:
 *   - up (TDP available)
 *     - CPU not busy, GPU not busy - nothing
 *     - CPU busy, GPU not busy - adjust CPU up
 *     - CPU not busy, GPU busy - adjust GPU up
 *     - CPU busy, GPU busy - adjust preferred unit up, taking headroom from
 *       non-preferred unit if necessary
 *   - down (at TDP limit)
 *     - adjust both CPU and GPU down if possible
 *
		cpu+ gpu+	cpu+gpu-	cpu-gpu+	cpu-gpu-
cpu < gpu <	cpu+gpu+	cpu+		gpu+		nothing
cpu < gpu >=	cpu+gpu-(mcp<)	cpu+gpu-(mcp<)	gpu-		gpu-
cpu >= gpu <	cpu-gpu+(mcp<)	cpu-		cpu-gpu+(mcp<)	cpu-
cpu >= gpu >=	cpu-gpu-	cpu-gpu-	cpu-gpu-	cpu-gpu-
 *
 */
static int ips_adjust(void *data)
{
	struct ips_driver *ips = data;
	unsigned long flags;

	dev_dbg(&ips->dev->dev, "starting ips-adjust thread\n");

	/*
	 * Adjust CPU and GPU clamps every 5s if needed.  Doing it more
	 * often isn't recommended due to ME interaction.
	 */
	do {
		bool cpu_busy = ips_cpu_busy(ips);
		bool gpu_busy = ips_gpu_busy(ips);

		spin_lock_irqsave(&ips->turbo_status_lock, flags);
		if (ips->poll_turbo_status)
			update_turbo_limits(ips);
		spin_unlock_irqrestore(&ips->turbo_status_lock, flags);

		/* Update turbo status if necessary */
		if (ips->cpu_turbo_enabled)
			ips_enable_cpu_turbo(ips);
		else
			ips_disable_cpu_turbo(ips);

		if (ips->gpu_turbo_enabled)
			ips_enable_gpu_turbo(ips);
		else
			ips_disable_gpu_turbo(ips);

		/* We're outside our comfort zone, crank them down */
		if (mcp_exceeded(ips)) {
			ips_cpu_lower(ips);
			ips_gpu_lower(ips);
			goto sleep;
		}

		if (!cpu_exceeded(ips, 0) && cpu_busy)
			ips_cpu_raise(ips);
		else
			ips_cpu_lower(ips);

		if (!mch_exceeded(ips) && gpu_busy)
			ips_gpu_raise(ips);
		else
			ips_gpu_lower(ips);

sleep:
		schedule_timeout_interruptible(msecs_to_jiffies(IPS_ADJUST_PERIOD));
	} while (!kthread_should_stop());

	dev_dbg(&ips->dev->dev, "ips-adjust thread stopped\n");

	return 0;
}

/*
 * Helpers for reading out temp/power values and calculating their
 * averages for the decision making and monitoring functions.
 */

static u16 calc_avg_temp(struct ips_driver *ips, u16 *array)
{
	u64 total = 0;
	int i;
	u16 avg;

	for (i = 0; i < IPS_SAMPLE_COUNT; i++)
		total += (u64)(array[i] * 100);

	do_div(total, IPS_SAMPLE_COUNT);

	avg = (u16)total;

	return avg;
}

static u16 read_mgtv(struct ips_driver *ips)
{
	u16 ret;
	u64 slope, offset;
	u64 val;

	val = thm_readq(THM_MGTV);
	val = (val & TV_MASK) >> TV_SHIFT;

	slope = offset = thm_readw(THM_MGTA);
	slope = (slope & MGTA_SLOPE_MASK) >> MGTA_SLOPE_SHIFT;
	offset = offset & MGTA_OFFSET_MASK;

	ret = ((val * slope + 0x40) >> 7) + offset;

	return 0; /* MCH temp reporting buggy */
}

static u16 read_ptv(struct ips_driver *ips)
{
	u16 val, slope, offset;

	slope = (ips->pta_val & PTA_SLOPE_MASK) >> PTA_SLOPE_SHIFT;
	offset = ips->pta_val & PTA_OFFSET_MASK;

	val = thm_readw(THM_PTV) & PTV_MASK;

	return val;
}

static u16 read_ctv(struct ips_driver *ips, int cpu)
{
	int reg = cpu ? THM_CTV2 : THM_CTV1;
	u16 val;

	val = thm_readw(reg);
	if (!(val & CTV_TEMP_ERROR))
		val = (val) >> 6; /* discard fractional component */
	else
		val = 0;

	return val;
}

static u32 get_cpu_power(struct ips_driver *ips, u32 *last, int period)
{
	u32 val;
	u32 ret;

	/*
	 * CEC is in joules/65535.  Take difference over time to
	 * get watts.
	 */
	val = thm_readl(THM_CEC);

	/* period is in ms and we want mW */
	ret = (((val - *last) * 1000) / period);
	ret = (ret * 1000) / 65535;
	*last = val;

	return 0;
}

static const u16 temp_decay_factor = 2;
static u16 update_average_temp(u16 avg, u16 val)
{
	u16 ret;

	/* Multiply by 100 for extra precision */
	ret = (val * 100 / temp_decay_factor) +
		(((temp_decay_factor - 1) * avg) / temp_decay_factor);
	return ret;
}

static const u16 power_decay_factor = 2;
static u16 update_average_power(u32 avg, u32 val)
{
	u32 ret;

	ret = (val / power_decay_factor) +
		(((power_decay_factor - 1) * avg) / power_decay_factor);

	return ret;
}

static u32 calc_avg_power(struct ips_driver *ips, u32 *array)
{
	u64 total = 0;
	u32 avg;
	int i;

	for (i = 0; i < IPS_SAMPLE_COUNT; i++)
		total += array[i];

	do_div(total, IPS_SAMPLE_COUNT);
	avg = (u32)total;

	return avg;
}

static void monitor_timeout(unsigned long arg)
{
	wake_up_process((struct task_struct *)arg);
}

/**
 * ips_monitor - temp/power monitoring thread
 * @data: ips driver structure
 *
 * This is the main function for the IPS driver.  It monitors power and
 * tempurature in the MCP and adjusts CPU and GPU power clams accordingly.
 *
 * We keep a 5s moving average of power consumption and tempurature.  Using
 * that data, along with CPU vs GPU preference, we adjust the power clamps
 * up or down.
 */
static int ips_monitor(void *data)
{
	struct ips_driver *ips = data;
	struct timer_list timer;
	unsigned long seqno_timestamp, expire, last_msecs, last_sample_period;
	int i;
	u32 *cpu_samples, *mchp_samples, old_cpu_power;
	u16 *mcp_samples, *ctv1_samples, *ctv2_samples, *mch_samples;
	u8 cur_seqno, last_seqno;

	mcp_samples = kzalloc(sizeof(u16) * IPS_SAMPLE_COUNT, GFP_KERNEL);
	ctv1_samples = kzalloc(sizeof(u16) * IPS_SAMPLE_COUNT, GFP_KERNEL);
	ctv2_samples = kzalloc(sizeof(u16) * IPS_SAMPLE_COUNT, GFP_KERNEL);
	mch_samples = kzalloc(sizeof(u16) * IPS_SAMPLE_COUNT, GFP_KERNEL);
	cpu_samples = kzalloc(sizeof(u32) * IPS_SAMPLE_COUNT, GFP_KERNEL);
	mchp_samples = kzalloc(sizeof(u32) * IPS_SAMPLE_COUNT, GFP_KERNEL);
	if (!mcp_samples || !ctv1_samples || !ctv2_samples || !mch_samples ||
			!cpu_samples || !mchp_samples) {
		dev_err(&ips->dev->dev,
			"failed to allocate sample array, ips disabled\n");
		kfree(mcp_samples);
		kfree(ctv1_samples);
		kfree(ctv2_samples);
		kfree(mch_samples);
		kfree(cpu_samples);
		kfree(mchp_samples);
		return -ENOMEM;
	}

	last_seqno = (thm_readl(THM_ITV) & ITV_ME_SEQNO_MASK) >>
		ITV_ME_SEQNO_SHIFT;
	seqno_timestamp = get_jiffies_64();

	old_cpu_power = thm_readl(THM_CEC);
	schedule_timeout_interruptible(msecs_to_jiffies(IPS_SAMPLE_PERIOD));

	/* Collect an initial average */
	for (i = 0; i < IPS_SAMPLE_COUNT; i++) {
		u32 mchp, cpu_power;
		u16 val;

		mcp_samples[i] = read_ptv(ips);

		val = read_ctv(ips, 0);
		ctv1_samples[i] = val;

		val = read_ctv(ips, 1);
		ctv2_samples[i] = val;

		val = read_mgtv(ips);
		mch_samples[i] = val;

		cpu_power = get_cpu_power(ips, &old_cpu_power,
					  IPS_SAMPLE_PERIOD);
		cpu_samples[i] = cpu_power;

		if (ips->read_mch_val) {
			mchp = ips->read_mch_val();
			mchp_samples[i] = mchp;
		}

		schedule_timeout_interruptible(msecs_to_jiffies(IPS_SAMPLE_PERIOD));
		if (kthread_should_stop())
			break;
	}

	ips->mcp_avg_temp = calc_avg_temp(ips, mcp_samples);
	ips->ctv1_avg_temp = calc_avg_temp(ips, ctv1_samples);
	ips->ctv2_avg_temp = calc_avg_temp(ips, ctv2_samples);
	ips->mch_avg_temp = calc_avg_temp(ips, mch_samples);
	ips->cpu_avg_power = calc_avg_power(ips, cpu_samples);
	ips->mch_avg_power = calc_avg_power(ips, mchp_samples);
	kfree(mcp_samples);
	kfree(ctv1_samples);
	kfree(ctv2_samples);
	kfree(mch_samples);
	kfree(cpu_samples);
	kfree(mchp_samples);

	/* Start the adjustment thread now that we have data */
	wake_up_process(ips->adjust);

	/*
	 * Ok, now we have an initial avg.  From here on out, we track the
	 * running avg using a decaying average calculation.  This allows
	 * us to reduce the sample frequency if the CPU and GPU are idle.
	 */
	old_cpu_power = thm_readl(THM_CEC);
	schedule_timeout_interruptible(msecs_to_jiffies(IPS_SAMPLE_PERIOD));
	last_sample_period = IPS_SAMPLE_PERIOD;

	setup_deferrable_timer_on_stack(&timer, monitor_timeout,
					(unsigned long)current);
	do {
		u32 cpu_val, mch_val;
		u16 val;

		/* MCP itself */
		val = read_ptv(ips);
		ips->mcp_avg_temp = update_average_temp(ips->mcp_avg_temp, val);

		/* Processor 0 */
		val = read_ctv(ips, 0);
		ips->ctv1_avg_temp =
			update_average_temp(ips->ctv1_avg_temp, val);
		/* Power */
		cpu_val = get_cpu_power(ips, &old_cpu_power,
					last_sample_period);
		ips->cpu_avg_power =
			update_average_power(ips->cpu_avg_power, cpu_val);

		if (ips->second_cpu) {
			/* Processor 1 */
			val = read_ctv(ips, 1);
			ips->ctv2_avg_temp =
				update_average_temp(ips->ctv2_avg_temp, val);
		}

		/* MCH */
		val = read_mgtv(ips);
		ips->mch_avg_temp = update_average_temp(ips->mch_avg_temp, val);
		/* Power */
		if (ips->read_mch_val) {
			mch_val = ips->read_mch_val();
			ips->mch_avg_power =
				update_average_power(ips->mch_avg_power,
						     mch_val);
		}

		/*
		 * Make sure ME is updating thermal regs.
		 * Note:
		 * If it's been more than a second since the last update,
		 * the ME is probably hung.
		 */
		cur_seqno = (thm_readl(THM_ITV) & ITV_ME_SEQNO_MASK) >>
			ITV_ME_SEQNO_SHIFT;
		if (cur_seqno == last_seqno &&
		    time_after(jiffies, seqno_timestamp + HZ)) {
			dev_warn(&ips->dev->dev, "ME failed to update for more than 1s, likely hung\n");
		} else {
			seqno_timestamp = get_jiffies_64();
			last_seqno = cur_seqno;
		}

		last_msecs = jiffies_to_msecs(jiffies);
		expire = jiffies + msecs_to_jiffies(IPS_SAMPLE_PERIOD);

		__set_current_state(TASK_INTERRUPTIBLE);
		mod_timer(&timer, expire);
		schedule();

		/* Calculate actual sample period for power averaging */
		last_sample_period = jiffies_to_msecs(jiffies) - last_msecs;
		if (!last_sample_period)
			last_sample_period = 1;
	} while (!kthread_should_stop());

	del_timer_sync(&timer);
	destroy_timer_on_stack(&timer);

	dev_dbg(&ips->dev->dev, "ips-monitor thread stopped\n");

	return 0;
}

#if 0
#define THM_DUMPW(reg) \
	{ \
	u16 val = thm_readw(reg); \
	dev_dbg(&ips->dev->dev, #reg ": 0x%04x\n", val); \
	}
#define THM_DUMPL(reg) \
	{ \
	u32 val = thm_readl(reg); \
	dev_dbg(&ips->dev->dev, #reg ": 0x%08x\n", val); \
	}
#define THM_DUMPQ(reg) \
	{ \
	u64 val = thm_readq(reg); \
	dev_dbg(&ips->dev->dev, #reg ": 0x%016x\n", val); \
	}

static void dump_thermal_info(struct ips_driver *ips)
{
	u16 ptl;

	ptl = thm_readw(THM_PTL);
	dev_dbg(&ips->dev->dev, "Processor temp limit: %d\n", ptl);

	THM_DUMPW(THM_CTA);
	THM_DUMPW(THM_TRC);
	THM_DUMPW(THM_CTV1);
	THM_DUMPL(THM_STS);
	THM_DUMPW(THM_PTV);
	THM_DUMPQ(THM_MGTV);
}
#endif

/**
 * ips_irq_handler - handle temperature triggers and other IPS events
 * @irq: irq number
 * @arg: unused
 *
 * Handle temperature limit trigger events, generally by lowering the clamps.
 * If we're at a critical limit, we clamp back to the lowest possible value
 * to prevent emergency shutdown.
 */
static irqreturn_t ips_irq_handler(int irq, void *arg)
{
	struct ips_driver *ips = arg;
	u8 tses = thm_readb(THM_TSES);
	u8 tes = thm_readb(THM_TES);

	if (!tses && !tes)
		return IRQ_NONE;

	dev_info(&ips->dev->dev, "TSES: 0x%02x\n", tses);
	dev_info(&ips->dev->dev, "TES: 0x%02x\n", tes);

	/* STS update from EC? */
	if (tes & 1) {
		u32 sts, tc1;

		sts = thm_readl(THM_STS);
		tc1 = thm_readl(THM_TC1);

		if (sts & STS_NVV) {
			spin_lock(&ips->turbo_status_lock);
			ips->core_power_limit = (sts & STS_PCPL_MASK) >>
				STS_PCPL_SHIFT;
			ips->mch_power_limit = (sts & STS_GPL_MASK) >>
				STS_GPL_SHIFT;
			/* ignore EC CPU vs GPU pref */
			ips->cpu_turbo_enabled = !(sts & STS_PCTD_DIS);
			/* 
			 * Disable turbo for now, until we can figure
			 * out why the power figures are wrong
			 */
			ips->cpu_turbo_enabled = false;
			if (ips->gpu_busy)
				ips->gpu_turbo_enabled = !(sts & STS_GTD_DIS);
			ips->mcp_temp_limit = (sts & STS_PTL_MASK) >>
				STS_PTL_SHIFT;
			ips->mcp_power_limit = (tc1 & STS_PPL_MASK) >>
				STS_PPL_SHIFT;
			verify_limits(ips);
			spin_unlock(&ips->turbo_status_lock);

			thm_writeb(THM_SEC, SEC_ACK);
		}
		thm_writeb(THM_TES, tes);
	}

	/* Thermal trip */
	if (tses) {
		dev_warn(&ips->dev->dev,
			 "thermal trip occurred, tses: 0x%04x\n", tses);
		thm_writeb(THM_TSES, tses);
	}

	return IRQ_HANDLED;
}

#ifndef CONFIG_DEBUG_FS
static void ips_debugfs_init(struct ips_driver *ips) { return; }
static void ips_debugfs_cleanup(struct ips_driver *ips) { return; }
#else

/* Expose current state and limits in debugfs if possible */

struct ips_debugfs_node {
	struct ips_driver *ips;
	char *name;
	int (*show)(struct seq_file *m, void *data);
};

static int show_cpu_temp(struct seq_file *m, void *data)
{
	struct ips_driver *ips = m->private;

	seq_printf(m, "%d.%02d\n", ips->ctv1_avg_temp / 100,
		   ips->ctv1_avg_temp % 100);

	return 0;
}

static int show_cpu_power(struct seq_file *m, void *data)
{
	struct ips_driver *ips = m->private;

	seq_printf(m, "%dmW\n", ips->cpu_avg_power);

	return 0;
}

static int show_cpu_clamp(struct seq_file *m, void *data)
{
	u64 turbo_override;
	int tdp, tdc;

	rdmsrl(TURBO_POWER_CURRENT_LIMIT, turbo_override);

	tdp = (int)(turbo_override & TURBO_TDP_MASK);
	tdc = (int)((turbo_override & TURBO_TDC_MASK) >> TURBO_TDC_SHIFT);

	/* Convert to .1W/A units */
	tdp = tdp * 10 / 8;
	tdc = tdc * 10 / 8;

	/* Watts Amperes */
	seq_printf(m, "%d.%dW %d.%dA\n", tdp / 10, tdp % 10,
		   tdc / 10, tdc % 10);

	return 0;
}

static int show_mch_temp(struct seq_file *m, void *data)
{
	struct ips_driver *ips = m->private;

	seq_printf(m, "%d.%02d\n", ips->mch_avg_temp / 100,
		   ips->mch_avg_temp % 100);

	return 0;
}

static int show_mch_power(struct seq_file *m, void *data)
{
	struct ips_driver *ips = m->private;

	seq_printf(m, "%dmW\n", ips->mch_avg_power);

	return 0;
}

static struct ips_debugfs_node ips_debug_files[] = {
	{ NULL, "cpu_temp", show_cpu_temp },
	{ NULL, "cpu_power", show_cpu_power },
	{ NULL, "cpu_clamp", show_cpu_clamp },
	{ NULL, "mch_temp", show_mch_temp },
	{ NULL, "mch_power", show_mch_power },
};

static int ips_debugfs_open(struct inode *inode, struct file *file)
{
	struct ips_debugfs_node *node = inode->i_private;

	return single_open(file, node->show, node->ips);
}

static const struct file_operations ips_debugfs_ops = {
	.owner = THIS_MODULE,
	.open = ips_debugfs_open,
	.read = seq_read,
	.llseek = seq_lseek,
	.release = single_release,
};

static void ips_debugfs_cleanup(struct ips_driver *ips)
{
	if (ips->debug_root)
		debugfs_remove_recursive(ips->debug_root);
	return;
}

static void ips_debugfs_init(struct ips_driver *ips)
{
	int i;

	ips->debug_root = debugfs_create_dir("ips", NULL);
	if (!ips->debug_root) {
		dev_err(&ips->dev->dev,
			"failed to create debugfs entries: %ld\n",
			PTR_ERR(ips->debug_root));
		return;
	}

	for (i = 0; i < ARRAY_SIZE(ips_debug_files); i++) {
		struct dentry *ent;
		struct ips_debugfs_node *node = &ips_debug_files[i];

		node->ips = ips;
		ent = debugfs_create_file(node->name, S_IFREG | S_IRUGO,
					  ips->debug_root, node,
					  &ips_debugfs_ops);
		if (!ent) {
			dev_err(&ips->dev->dev,
				"failed to create debug file: %ld\n",
				PTR_ERR(ent));
			goto err_cleanup;
		}
	}

	return;

err_cleanup:
	ips_debugfs_cleanup(ips);
	return;
}
#endif /* CONFIG_DEBUG_FS */

/**
 * ips_detect_cpu - detect whether CPU supports IPS
 *
 * Walk our list and see if we're on a supported CPU.  If we find one,
 * return the limits for it.
 */
static struct ips_mcp_limits *ips_detect_cpu(struct ips_driver *ips)
{
	u64 turbo_power, misc_en;
	struct ips_mcp_limits *limits = NULL;
	u16 tdp;

	if (!(boot_cpu_data.x86 == 6 && boot_cpu_data.x86_model == 37)) {
		dev_info(&ips->dev->dev, "Non-IPS CPU detected.\n");
		goto out;
	}

	rdmsrl(IA32_MISC_ENABLE, misc_en);
	/*
	 * If the turbo enable bit isn't set, we shouldn't try to enable/disable
	 * turbo manually or we'll get an illegal MSR access, even though
	 * turbo will still be available.
	 */
	if (misc_en & IA32_MISC_TURBO_EN)
		ips->turbo_toggle_allowed = true;
	else
		ips->turbo_toggle_allowed = false;

	if (strstr(boot_cpu_data.x86_model_id, "CPU       M"))
		limits = &ips_sv_limits;
	else if (strstr(boot_cpu_data.x86_model_id, "CPU       L"))
		limits = &ips_lv_limits;
	else if (strstr(boot_cpu_data.x86_model_id, "CPU       U"))
		limits = &ips_ulv_limits;
	else {
		dev_info(&ips->dev->dev, "No CPUID match found.\n");
		goto out;
	}

	rdmsrl(TURBO_POWER_CURRENT_LIMIT, turbo_power);
	tdp = turbo_power & TURBO_TDP_MASK;

	/* Sanity check TDP against CPU */
	if (limits->core_power_limit != (tdp / 8) * 1000) {
		dev_info(&ips->dev->dev, "CPU TDP doesn't match expected value (found %d, expected %d)\n",
			 tdp / 8, limits->core_power_limit / 1000);
		limits->core_power_limit = (tdp / 8) * 1000;
	}

out:
	return limits;
}

/**
 * ips_get_i915_syms - try to get GPU control methods from i915 driver
 * @ips: IPS driver
 *
 * The i915 driver exports several interfaces to allow the IPS driver to
 * monitor and control graphics turbo mode.  If we can find them, we can
 * enable graphics turbo, otherwise we must disable it to avoid exceeding
 * thermal and power limits in the MCP.
 */
static bool ips_get_i915_syms(struct ips_driver *ips)
{
	ips->read_mch_val = symbol_get(i915_read_mch_val);
	if (!ips->read_mch_val)
		goto out_err;
	ips->gpu_raise = symbol_get(i915_gpu_raise);
	if (!ips->gpu_raise)
		goto out_put_mch;
	ips->gpu_lower = symbol_get(i915_gpu_lower);
	if (!ips->gpu_lower)
		goto out_put_raise;
	ips->gpu_busy = symbol_get(i915_gpu_busy);
	if (!ips->gpu_busy)
		goto out_put_lower;
	ips->gpu_turbo_disable = symbol_get(i915_gpu_turbo_disable);
	if (!ips->gpu_turbo_disable)
		goto out_put_busy;

	return true;

out_put_busy:
	symbol_put(i915_gpu_busy);
out_put_lower:
	symbol_put(i915_gpu_lower);
out_put_raise:
	symbol_put(i915_gpu_raise);
out_put_mch:
	symbol_put(i915_read_mch_val);
out_err:
	return false;
}

static bool
ips_gpu_turbo_enabled(struct ips_driver *ips)
{
	if (!ips->gpu_busy && late_i915_load) {
		if (ips_get_i915_syms(ips)) {
			dev_info(&ips->dev->dev,
				 "i915 driver attached, reenabling gpu turbo\n");
			ips->gpu_turbo_enabled = !(thm_readl(THM_HTS) & HTS_GTD_DIS);
		}
	}

	return ips->gpu_turbo_enabled;
}

void
ips_link_to_i915_driver(void)
{
	/* We can't cleanly get at the various ips_driver structs from
	 * this caller (the i915 driver), so just set a flag saying
	 * that it's time to try getting the symbols again.
	 */
	late_i915_load = true;
}
EXPORT_SYMBOL_GPL(ips_link_to_i915_driver);

static DEFINE_PCI_DEVICE_TABLE(ips_id_table) = {
	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL,
		     PCI_DEVICE_ID_INTEL_THERMAL_SENSOR), },
	{ 0, }
};

MODULE_DEVICE_TABLE(pci, ips_id_table);

static int ips_probe(struct pci_dev *dev, const struct pci_device_id *id)
{
	u64 platform_info;
	struct ips_driver *ips;
	u32 hts;
	int ret = 0;
	u16 htshi, trc, trc_required_mask;
	u8 tse;

	ips = kzalloc(sizeof(struct ips_driver), GFP_KERNEL);
	if (!ips)
		return -ENOMEM;

	pci_set_drvdata(dev, ips);
	ips->dev = dev;

	ips->limits = ips_detect_cpu(ips);
	if (!ips->limits) {
		dev_info(&dev->dev, "IPS not supported on this CPU\n");
		ret = -ENXIO;
		goto error_free;
	}

	spin_lock_init(&ips->turbo_status_lock);

	ret = pci_enable_device(dev);
	if (ret) {
		dev_err(&dev->dev, "can't enable PCI device, aborting\n");
		goto error_free;
	}

	if (!pci_resource_start(dev, 0)) {
		dev_err(&dev->dev, "TBAR not assigned, aborting\n");
		ret = -ENXIO;
		goto error_free;
	}

	ret = pci_request_regions(dev, "ips thermal sensor");
	if (ret) {
		dev_err(&dev->dev, "thermal resource busy, aborting\n");
		goto error_free;
	}


	ips->regmap = ioremap(pci_resource_start(dev, 0),
			      pci_resource_len(dev, 0));
	if (!ips->regmap) {
		dev_err(&dev->dev, "failed to map thermal regs, aborting\n");
		ret = -EBUSY;
		goto error_release;
	}

	tse = thm_readb(THM_TSE);
	if (tse != TSE_EN) {
		dev_err(&dev->dev, "thermal device not enabled (0x%02x), aborting\n", tse);
		ret = -ENXIO;
		goto error_unmap;
	}

	trc = thm_readw(THM_TRC);
	trc_required_mask = TRC_CORE1_EN | TRC_CORE_PWR | TRC_MCH_EN;
	if ((trc & trc_required_mask) != trc_required_mask) {
		dev_err(&dev->dev, "thermal reporting for required devices not enabled, aborting\n");
		ret = -ENXIO;
		goto error_unmap;
	}

	if (trc & TRC_CORE2_EN)
		ips->second_cpu = true;

	update_turbo_limits(ips);
	dev_dbg(&dev->dev, "max cpu power clamp: %dW\n",
		ips->mcp_power_limit / 10);
	dev_dbg(&dev->dev, "max core power clamp: %dW\n",
		ips->core_power_limit / 10);
	/* BIOS may update limits at runtime */
	if (thm_readl(THM_PSC) & PSP_PBRT)
		ips->poll_turbo_status = true;

	if (!ips_get_i915_syms(ips)) {
		dev_info(&dev->dev, "failed to get i915 symbols, graphics turbo disabled until i915 loads\n");
		ips->gpu_turbo_enabled = false;
	} else {
		dev_dbg(&dev->dev, "graphics turbo enabled\n");
		ips->gpu_turbo_enabled = true;
	}

	/*
	 * Check PLATFORM_INFO MSR to make sure this chip is
	 * turbo capable.
	 */
	rdmsrl(PLATFORM_INFO, platform_info);
	if (!(platform_info & PLATFORM_TDP)) {
		dev_err(&dev->dev, "platform indicates TDP override unavailable, aborting\n");
		ret = -ENODEV;
		goto error_unmap;
	}

	/*
	 * IRQ handler for ME interaction
	 * Note: don't use MSI here as the PCH has bugs.
	 */
	pci_disable_msi(dev);
	ret = request_irq(dev->irq, ips_irq_handler, IRQF_SHARED, "ips",
			  ips);
	if (ret) {
		dev_err(&dev->dev, "request irq failed, aborting\n");
		goto error_unmap;
	}

	/* Enable aux, hot & critical interrupts */
	thm_writeb(THM_TSPIEN, TSPIEN_AUX2_LOHI | TSPIEN_CRIT_LOHI |
		   TSPIEN_HOT_LOHI | TSPIEN_AUX_LOHI);
	thm_writeb(THM_TEN, TEN_UPDATE_EN);

	/* Collect adjustment values */
	ips->cta_val = thm_readw(THM_CTA);
	ips->pta_val = thm_readw(THM_PTA);
	ips->mgta_val = thm_readw(THM_MGTA);

	/* Save turbo limits & ratios */
	rdmsrl(TURBO_POWER_CURRENT_LIMIT, ips->orig_turbo_limit);

	ips_disable_cpu_turbo(ips);
	ips->cpu_turbo_enabled = false;

	/* Create thermal adjust thread */
	ips->adjust = kthread_create(ips_adjust, ips, "ips-adjust");
	if (IS_ERR(ips->adjust)) {
		dev_err(&dev->dev,
			"failed to create thermal adjust thread, aborting\n");
		ret = -ENOMEM;
		goto error_free_irq;

	}

	/*
	 * Set up the work queue and monitor thread. The monitor thread
	 * will wake up ips_adjust thread.
	 */
	ips->monitor = kthread_run(ips_monitor, ips, "ips-monitor");
	if (IS_ERR(ips->monitor)) {
		dev_err(&dev->dev,
			"failed to create thermal monitor thread, aborting\n");
		ret = -ENOMEM;
		goto error_thread_cleanup;
	}

	hts = (ips->core_power_limit << HTS_PCPL_SHIFT) |
		(ips->mcp_temp_limit << HTS_PTL_SHIFT) | HTS_NVV;
	htshi = HTS2_PRST_RUNNING << HTS2_PRST_SHIFT;

	thm_writew(THM_HTSHI, htshi);
	thm_writel(THM_HTS, hts);

	ips_debugfs_init(ips);

	dev_info(&dev->dev, "IPS driver initialized, MCP temp limit %d\n",
		 ips->mcp_temp_limit);
	return ret;

error_thread_cleanup:
	kthread_stop(ips->adjust);
error_free_irq:
	free_irq(ips->dev->irq, ips);
error_unmap:
	iounmap(ips->regmap);
error_release:
	pci_release_regions(dev);
error_free:
	kfree(ips);
	return ret;
}

static void ips_remove(struct pci_dev *dev)
{
	struct ips_driver *ips = pci_get_drvdata(dev);
	u64 turbo_override;

	if (!ips)
		return;

	ips_debugfs_cleanup(ips);

	/* Release i915 driver */
	if (ips->read_mch_val)
		symbol_put(i915_read_mch_val);
	if (ips->gpu_raise)
		symbol_put(i915_gpu_raise);
	if (ips->gpu_lower)
		symbol_put(i915_gpu_lower);
	if (ips->gpu_busy)
		symbol_put(i915_gpu_busy);
	if (ips->gpu_turbo_disable)
		symbol_put(i915_gpu_turbo_disable);

	rdmsrl(TURBO_POWER_CURRENT_LIMIT, turbo_override);
	turbo_override &= ~(TURBO_TDC_OVR_EN | TURBO_TDP_OVR_EN);
	wrmsrl(TURBO_POWER_CURRENT_LIMIT, turbo_override);
	wrmsrl(TURBO_POWER_CURRENT_LIMIT, ips->orig_turbo_limit);

	free_irq(ips->dev->irq, ips);
	if (ips->adjust)
		kthread_stop(ips->adjust);
	if (ips->monitor)
		kthread_stop(ips->monitor);
	iounmap(ips->regmap);
	pci_release_regions(dev);
	kfree(ips);
	dev_dbg(&dev->dev, "IPS driver removed\n");
}

#ifdef CONFIG_PM
static int ips_suspend(struct pci_dev *dev, pm_message_t state)
{
	return 0;
}

static int ips_resume(struct pci_dev *dev)
{
	return 0;
}
#else
#define ips_suspend NULL
#define ips_resume NULL
#endif /* CONFIG_PM */

static void ips_shutdown(struct pci_dev *dev)
{
}

static struct pci_driver ips_pci_driver = {
	.name = "intel ips",
	.id_table = ips_id_table,
	.probe = ips_probe,
	.remove = ips_remove,
	.suspend = ips_suspend,
	.resume = ips_resume,
	.shutdown = ips_shutdown,
};

static int __init ips_init(void)
{
	return pci_register_driver(&ips_pci_driver);
}
module_init(ips_init);

static void ips_exit(void)
{
	pci_unregister_driver(&ips_pci_driver);
	return;
}
module_exit(ips_exit);

MODULE_LICENSE("GPL");
MODULE_AUTHOR("Jesse Barnes <jbarnes@virtuousgeek.org>");
MODULE_DESCRIPTION("Intelligent Power Sharing Driver");