summaryrefslogtreecommitdiffstats
path: root/drivers/pci/hotplug/pciehp_hpc.c
blob: 891f81a0400c92cb434dcdbbee95dbfa96c0e213 (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
/*
 * PCI Express PCI Hot Plug Driver
 *
 * Copyright (C) 1995,2001 Compaq Computer Corporation
 * Copyright (C) 2001 Greg Kroah-Hartman (greg@kroah.com)
 * Copyright (C) 2001 IBM Corp.
 * Copyright (C) 2003-2004 Intel Corporation
 *
 * All rights reserved.
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or (at
 * your option) any later version.
 *
 * This program is distributed in the hope that it will be useful, but
 * WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, GOOD TITLE or
 * NON INFRINGEMENT.  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., 675 Mass Ave, Cambridge, MA 02139, USA.
 *
 * Send feedback to <greg@kroah.com>,<kristen.c.accardi@intel.com>
 *
 */

#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/types.h>
#include <linux/signal.h>
#include <linux/jiffies.h>
#include <linux/timer.h>
#include <linux/pci.h>
#include <linux/interrupt.h>
#include <linux/time.h>

#include "../pci.h"
#include "pciehp.h"

static atomic_t pciehp_num_controllers = ATOMIC_INIT(0);

struct ctrl_reg {
	u8 cap_id;
	u8 nxt_ptr;
	u16 cap_reg;
	u32 dev_cap;
	u16 dev_ctrl;
	u16 dev_status;
	u32 lnk_cap;
	u16 lnk_ctrl;
	u16 lnk_status;
	u32 slot_cap;
	u16 slot_ctrl;
	u16 slot_status;
	u16 root_ctrl;
	u16 rsvp;
	u32 root_status;
} __attribute__ ((packed));

/* offsets to the controller registers based on the above structure layout */
enum ctrl_offsets {
	PCIECAPID	=	offsetof(struct ctrl_reg, cap_id),
	NXTCAPPTR	=	offsetof(struct ctrl_reg, nxt_ptr),
	CAPREG		=	offsetof(struct ctrl_reg, cap_reg),
	DEVCAP		=	offsetof(struct ctrl_reg, dev_cap),
	DEVCTRL		=	offsetof(struct ctrl_reg, dev_ctrl),
	DEVSTATUS	=	offsetof(struct ctrl_reg, dev_status),
	LNKCAP		=	offsetof(struct ctrl_reg, lnk_cap),
	LNKCTRL		=	offsetof(struct ctrl_reg, lnk_ctrl),
	LNKSTATUS	=	offsetof(struct ctrl_reg, lnk_status),
	SLOTCAP		=	offsetof(struct ctrl_reg, slot_cap),
	SLOTCTRL	=	offsetof(struct ctrl_reg, slot_ctrl),
	SLOTSTATUS	=	offsetof(struct ctrl_reg, slot_status),
	ROOTCTRL	=	offsetof(struct ctrl_reg, root_ctrl),
	ROOTSTATUS	=	offsetof(struct ctrl_reg, root_status),
};

static inline int pciehp_readw(struct controller *ctrl, int reg, u16 *value)
{
	struct pci_dev *dev = ctrl->pci_dev;
	return pci_read_config_word(dev, ctrl->cap_base + reg, value);
}

static inline int pciehp_readl(struct controller *ctrl, int reg, u32 *value)
{
	struct pci_dev *dev = ctrl->pci_dev;
	return pci_read_config_dword(dev, ctrl->cap_base + reg, value);
}

static inline int pciehp_writew(struct controller *ctrl, int reg, u16 value)
{
	struct pci_dev *dev = ctrl->pci_dev;
	return pci_write_config_word(dev, ctrl->cap_base + reg, value);
}

static inline int pciehp_writel(struct controller *ctrl, int reg, u32 value)
{
	struct pci_dev *dev = ctrl->pci_dev;
	return pci_write_config_dword(dev, ctrl->cap_base + reg, value);
}

/* Field definitions in PCI Express Capabilities Register */
#define CAP_VER			0x000F
#define DEV_PORT_TYPE		0x00F0
#define SLOT_IMPL		0x0100
#define MSG_NUM			0x3E00

/* Device or Port Type */
#define NAT_ENDPT		0x00
#define LEG_ENDPT		0x01
#define ROOT_PORT		0x04
#define UP_STREAM		0x05
#define	DN_STREAM		0x06
#define PCIE_PCI_BRDG		0x07
#define PCI_PCIE_BRDG		0x10

/* Field definitions in Device Capabilities Register */
#define DATTN_BUTTN_PRSN	0x1000
#define DATTN_LED_PRSN		0x2000
#define DPWR_LED_PRSN		0x4000

/* Field definitions in Link Capabilities Register */
#define MAX_LNK_SPEED		0x000F
#define MAX_LNK_WIDTH		0x03F0

/* Link Width Encoding */
#define LNK_X1		0x01
#define LNK_X2		0x02
#define LNK_X4		0x04
#define LNK_X8		0x08
#define LNK_X12		0x0C
#define LNK_X16		0x10
#define LNK_X32		0x20

/*Field definitions of Link Status Register */
#define LNK_SPEED	0x000F
#define NEG_LINK_WD	0x03F0
#define LNK_TRN_ERR	0x0400
#define	LNK_TRN		0x0800
#define SLOT_CLK_CONF	0x1000

/* Field definitions in Slot Capabilities Register */
#define ATTN_BUTTN_PRSN	0x00000001
#define	PWR_CTRL_PRSN	0x00000002
#define MRL_SENS_PRSN	0x00000004
#define ATTN_LED_PRSN	0x00000008
#define PWR_LED_PRSN	0x00000010
#define HP_SUPR_RM_SUP	0x00000020
#define HP_CAP		0x00000040
#define SLOT_PWR_VALUE	0x000003F8
#define SLOT_PWR_LIMIT	0x00000C00
#define PSN		0xFFF80000	/* PSN: Physical Slot Number */

/* Field definitions in Slot Control Register */
#define ATTN_BUTTN_ENABLE		0x0001
#define PWR_FAULT_DETECT_ENABLE		0x0002
#define MRL_DETECT_ENABLE		0x0004
#define PRSN_DETECT_ENABLE		0x0008
#define CMD_CMPL_INTR_ENABLE		0x0010
#define HP_INTR_ENABLE			0x0020
#define ATTN_LED_CTRL			0x00C0
#define PWR_LED_CTRL			0x0300
#define PWR_CTRL			0x0400
#define EMI_CTRL			0x0800

/* Attention indicator and Power indicator states */
#define LED_ON		0x01
#define LED_BLINK	0x10
#define LED_OFF		0x11

/* Power Control Command */
#define POWER_ON	0
#define POWER_OFF	0x0400

/* EMI Status defines */
#define EMI_DISENGAGED	0
#define EMI_ENGAGED	1

/* Field definitions in Slot Status Register */
#define ATTN_BUTTN_PRESSED	0x0001
#define PWR_FAULT_DETECTED	0x0002
#define MRL_SENS_CHANGED	0x0004
#define PRSN_DETECT_CHANGED	0x0008
#define CMD_COMPLETED		0x0010
#define MRL_STATE		0x0020
#define PRSN_STATE		0x0040
#define EMI_STATE		0x0080
#define EMI_STATUS_BIT		7

static irqreturn_t pcie_isr(int irq, void *dev_id);
static void start_int_poll_timer(struct controller *ctrl, int sec);

/* This is the interrupt polling timeout function. */
static void int_poll_timeout(unsigned long data)
{
	struct controller *ctrl = (struct controller *)data;

	/* Poll for interrupt events.  regs == NULL => polling */
	pcie_isr(0, ctrl);

	init_timer(&ctrl->poll_timer);
	if (!pciehp_poll_time)
		pciehp_poll_time = 2; /* default polling interval is 2 sec */

	start_int_poll_timer(ctrl, pciehp_poll_time);
}

/* This function starts the interrupt polling timer. */
static void start_int_poll_timer(struct controller *ctrl, int sec)
{
	/* Clamp to sane value */
	if ((sec <= 0) || (sec > 60))
        	sec = 2;

	ctrl->poll_timer.function = &int_poll_timeout;
	ctrl->poll_timer.data = (unsigned long)ctrl;
	ctrl->poll_timer.expires = jiffies + sec * HZ;
	add_timer(&ctrl->poll_timer);
}

static inline int pciehp_request_irq(struct controller *ctrl)
{
	int retval, irq = ctrl->pci_dev->irq;

	/* Install interrupt polling timer. Start with 10 sec delay */
	if (pciehp_poll_mode) {
		init_timer(&ctrl->poll_timer);
		start_int_poll_timer(ctrl, 10);
		return 0;
	}

	/* Installs the interrupt handler */
	retval = request_irq(irq, pcie_isr, IRQF_SHARED, MY_NAME, ctrl);
	if (retval)
		err("Cannot get irq %d for the hotplug controller\n", irq);
	return retval;
}

static inline void pciehp_free_irq(struct controller *ctrl)
{
	if (pciehp_poll_mode)
		del_timer_sync(&ctrl->poll_timer);
	else
		free_irq(ctrl->pci_dev->irq, ctrl);
}

static inline int pcie_wait_cmd(struct controller *ctrl)
{
	int retval = 0;
	unsigned int msecs = pciehp_poll_mode ? 2500 : 1000;
	unsigned long timeout = msecs_to_jiffies(msecs);
	int rc;

	rc = wait_event_interruptible_timeout(ctrl->queue,
					      !ctrl->cmd_busy, timeout);
	if (!rc)
		dbg("Command not completed in 1000 msec\n");
	else if (rc < 0) {
		retval = -EINTR;
		info("Command was interrupted by a signal\n");
	}

	return retval;
}

/**
 * pcie_write_cmd - Issue controller command
 * @ctrl: controller to which the command is issued
 * @cmd:  command value written to slot control register
 * @mask: bitmask of slot control register to be modified
 */
static int pcie_write_cmd(struct controller *ctrl, u16 cmd, u16 mask)
{
	int retval = 0;
	u16 slot_status;
	u16 slot_ctrl;

	mutex_lock(&ctrl->ctrl_lock);

	retval = pciehp_readw(ctrl, SLOTSTATUS, &slot_status);
	if (retval) {
		err("%s: Cannot read SLOTSTATUS register\n", __func__);
		goto out;
	}

	if ((slot_status & CMD_COMPLETED) == CMD_COMPLETED ) {
		/* After 1 sec and CMD_COMPLETED still not set, just
		   proceed forward to issue the next command according
		   to spec.  Just print out the error message */
		dbg("%s: CMD_COMPLETED not clear after 1 sec.\n",
		    __func__);
	}

	retval = pciehp_readw(ctrl, SLOTCTRL, &slot_ctrl);
	if (retval) {
		err("%s: Cannot read SLOTCTRL register\n", __func__);
		goto out;
	}

	slot_ctrl &= ~mask;
	slot_ctrl |= (cmd & mask);
	/* Don't enable command completed if caller is changing it. */
	if (!(mask & CMD_CMPL_INTR_ENABLE))
		slot_ctrl |= CMD_CMPL_INTR_ENABLE;

	ctrl->cmd_busy = 1;
	smp_mb();
	retval = pciehp_writew(ctrl, SLOTCTRL, slot_ctrl);
	if (retval)
		err("%s: Cannot write to SLOTCTRL register\n", __func__);

	/*
	 * Wait for command completion.
	 */
	if (!retval)
		retval = pcie_wait_cmd(ctrl);
 out:
	mutex_unlock(&ctrl->ctrl_lock);
	return retval;
}

static int hpc_check_lnk_status(struct controller *ctrl)
{
	u16 lnk_status;
	int retval = 0;

	retval = pciehp_readw(ctrl, LNKSTATUS, &lnk_status);
	if (retval) {
		err("%s: Cannot read LNKSTATUS register\n", __func__);
		return retval;
	}

	dbg("%s: lnk_status = %x\n", __func__, lnk_status);
	if ( (lnk_status & LNK_TRN) || (lnk_status & LNK_TRN_ERR) ||
		!(lnk_status & NEG_LINK_WD)) {
		err("%s : Link Training Error occurs \n", __func__);
		retval = -1;
		return retval;
	}

	return retval;
}

static int hpc_get_attention_status(struct slot *slot, u8 *status)
{
	struct controller *ctrl = slot->ctrl;
	u16 slot_ctrl;
	u8 atten_led_state;
	int retval = 0;

	retval = pciehp_readw(ctrl, SLOTCTRL, &slot_ctrl);
	if (retval) {
		err("%s: Cannot read SLOTCTRL register\n", __func__);
		return retval;
	}

	dbg("%s: SLOTCTRL %x, value read %x\n",
	    __func__, ctrl->cap_base + SLOTCTRL, slot_ctrl);

	atten_led_state = (slot_ctrl & ATTN_LED_CTRL) >> 6;

	switch (atten_led_state) {
	case 0:
		*status = 0xFF;	/* Reserved */
		break;
	case 1:
		*status = 1;	/* On */
		break;
	case 2:
		*status = 2;	/* Blink */
		break;
	case 3:
		*status = 0;	/* Off */
		break;
	default:
		*status = 0xFF;
		break;
	}

	return 0;
}

static int hpc_get_power_status(struct slot *slot, u8 *status)
{
	struct controller *ctrl = slot->ctrl;
	u16 slot_ctrl;
	u8 pwr_state;
	int	retval = 0;

	retval = pciehp_readw(ctrl, SLOTCTRL, &slot_ctrl);
	if (retval) {
		err("%s: Cannot read SLOTCTRL register\n", __func__);
		return retval;
	}
	dbg("%s: SLOTCTRL %x value read %x\n",
	    __func__, ctrl->cap_base + SLOTCTRL, slot_ctrl);

	pwr_state = (slot_ctrl & PWR_CTRL) >> 10;

	switch (pwr_state) {
	case 0:
		*status = 1;
		break;
	case 1:
		*status = 0;
		break;
	default:
		*status = 0xFF;
		break;
	}

	return retval;
}

static int hpc_get_latch_status(struct slot *slot, u8 *status)
{
	struct controller *ctrl = slot->ctrl;
	u16 slot_status;
	int retval = 0;

	retval = pciehp_readw(ctrl, SLOTSTATUS, &slot_status);
	if (retval) {
		err("%s: Cannot read SLOTSTATUS register\n", __func__);
		return retval;
	}

	*status = (((slot_status & MRL_STATE) >> 5) == 0) ? 0 : 1;

	return 0;
}

static int hpc_get_adapter_status(struct slot *slot, u8 *status)
{
	struct controller *ctrl = slot->ctrl;
	u16 slot_status;
	u8 card_state;
	int retval = 0;

	retval = pciehp_readw(ctrl, SLOTSTATUS, &slot_status);
	if (retval) {
		err("%s: Cannot read SLOTSTATUS register\n", __func__);
		return retval;
	}
	card_state = (u8)((slot_status & PRSN_STATE) >> 6);
	*status = (card_state == 1) ? 1 : 0;

	return 0;
}

static int hpc_query_power_fault(struct slot *slot)
{
	struct controller *ctrl = slot->ctrl;
	u16 slot_status;
	u8 pwr_fault;
	int retval = 0;

	retval = pciehp_readw(ctrl, SLOTSTATUS, &slot_status);
	if (retval) {
		err("%s: Cannot check for power fault\n", __func__);
		return retval;
	}
	pwr_fault = (u8)((slot_status & PWR_FAULT_DETECTED) >> 1);

	return pwr_fault;
}

static int hpc_get_emi_status(struct slot *slot, u8 *status)
{
	struct controller *ctrl = slot->ctrl;
	u16 slot_status;
	int retval = 0;

	retval = pciehp_readw(ctrl, SLOTSTATUS, &slot_status);
	if (retval) {
		err("%s : Cannot check EMI status\n", __func__);
		return retval;
	}
	*status = (slot_status & EMI_STATE) >> EMI_STATUS_BIT;

	return retval;
}

static int hpc_toggle_emi(struct slot *slot)
{
	u16 slot_cmd;
	u16 cmd_mask;
	int rc;

	slot_cmd = EMI_CTRL;
	cmd_mask = EMI_CTRL;
	rc = pcie_write_cmd(slot->ctrl, slot_cmd, cmd_mask);
	slot->last_emi_toggle = get_seconds();

	return rc;
}

static int hpc_set_attention_status(struct slot *slot, u8 value)
{
	struct controller *ctrl = slot->ctrl;
	u16 slot_cmd;
	u16 cmd_mask;
	int rc;

	cmd_mask = ATTN_LED_CTRL;
	switch (value) {
		case 0 :	/* turn off */
			slot_cmd = 0x00C0;
			break;
		case 1:		/* turn on */
			slot_cmd = 0x0040;
			break;
		case 2:		/* turn blink */
			slot_cmd = 0x0080;
			break;
		default:
			return -1;
	}
	rc = pcie_write_cmd(ctrl, slot_cmd, cmd_mask);
	dbg("%s: SLOTCTRL %x write cmd %x\n",
	    __func__, ctrl->cap_base + SLOTCTRL, slot_cmd);

	return rc;
}

static void hpc_set_green_led_on(struct slot *slot)
{
	struct controller *ctrl = slot->ctrl;
	u16 slot_cmd;
	u16 cmd_mask;

	slot_cmd = 0x0100;
	cmd_mask = PWR_LED_CTRL;
	pcie_write_cmd(ctrl, slot_cmd, cmd_mask);
	dbg("%s: SLOTCTRL %x write cmd %x\n",
	    __func__, ctrl->cap_base + SLOTCTRL, slot_cmd);
}

static void hpc_set_green_led_off(struct slot *slot)
{
	struct controller *ctrl = slot->ctrl;
	u16 slot_cmd;
	u16 cmd_mask;

	slot_cmd = 0x0300;
	cmd_mask = PWR_LED_CTRL;
	pcie_write_cmd(ctrl, slot_cmd, cmd_mask);
	dbg("%s: SLOTCTRL %x write cmd %x\n",
	    __func__, ctrl->cap_base + SLOTCTRL, slot_cmd);
}

static void hpc_set_green_led_blink(struct slot *slot)
{
	struct controller *ctrl = slot->ctrl;
	u16 slot_cmd;
	u16 cmd_mask;

	slot_cmd = 0x0200;
	cmd_mask = PWR_LED_CTRL;
	pcie_write_cmd(ctrl, slot_cmd, cmd_mask);
	dbg("%s: SLOTCTRL %x write cmd %x\n",
	    __func__, ctrl->cap_base + SLOTCTRL, slot_cmd);
}

static void hpc_release_ctlr(struct controller *ctrl)
{
	/* Mask Hot-plug Interrupt Enable */
	if (pcie_write_cmd(ctrl, 0, HP_INTR_ENABLE | CMD_CMPL_INTR_ENABLE))
		err("%s: Cannot mask hotplut interrupt enable\n", __func__);

	/* Free interrupt handler or interrupt polling timer */
	pciehp_free_irq(ctrl);

	/*
	 * If this is the last controller to be released, destroy the
	 * pciehp work queue
	 */
	if (atomic_dec_and_test(&pciehp_num_controllers))
		destroy_workqueue(pciehp_wq);
}

static int hpc_power_on_slot(struct slot * slot)
{
	struct controller *ctrl = slot->ctrl;
	u16 slot_cmd;
	u16 cmd_mask;
	u16 slot_status;
	int retval = 0;

	dbg("%s: slot->hp_slot %x\n", __func__, slot->hp_slot);

	/* Clear sticky power-fault bit from previous power failures */
	retval = pciehp_readw(ctrl, SLOTSTATUS, &slot_status);
	if (retval) {
		err("%s: Cannot read SLOTSTATUS register\n", __func__);
		return retval;
	}
	slot_status &= PWR_FAULT_DETECTED;
	if (slot_status) {
		retval = pciehp_writew(ctrl, SLOTSTATUS, slot_status);
		if (retval) {
			err("%s: Cannot write to SLOTSTATUS register\n",
			    __func__);
			return retval;
		}
	}

	slot_cmd = POWER_ON;
	cmd_mask = PWR_CTRL;
	/* Enable detection that we turned off at slot power-off time */
	if (!pciehp_poll_mode) {
		slot_cmd |= (PWR_FAULT_DETECT_ENABLE | MRL_DETECT_ENABLE |
			     PRSN_DETECT_ENABLE);
		cmd_mask |= (PWR_FAULT_DETECT_ENABLE | MRL_DETECT_ENABLE |
			     PRSN_DETECT_ENABLE);
	}

	retval = pcie_write_cmd(ctrl, slot_cmd, cmd_mask);

	if (retval) {
		err("%s: Write %x command failed!\n", __func__, slot_cmd);
		return -1;
	}
	dbg("%s: SLOTCTRL %x write cmd %x\n",
	    __func__, ctrl->cap_base + SLOTCTRL, slot_cmd);

	return retval;
}

static inline int pcie_mask_bad_dllp(struct controller *ctrl)
{
	struct pci_dev *dev = ctrl->pci_dev;
	int pos;
	u32 reg;

	pos = pci_find_ext_capability(dev, PCI_EXT_CAP_ID_ERR);
	if (!pos)
		return 0;
	pci_read_config_dword(dev, pos + PCI_ERR_COR_MASK, &reg);
	if (reg & PCI_ERR_COR_BAD_DLLP)
		return 0;
	reg |= PCI_ERR_COR_BAD_DLLP;
	pci_write_config_dword(dev, pos + PCI_ERR_COR_MASK, reg);
	return 1;
}

static inline void pcie_unmask_bad_dllp(struct controller *ctrl)
{
	struct pci_dev *dev = ctrl->pci_dev;
	u32 reg;
	int pos;

	pos = pci_find_ext_capability(dev, PCI_EXT_CAP_ID_ERR);
	if (!pos)
		return;
	pci_read_config_dword(dev, pos + PCI_ERR_COR_MASK, &reg);
	if (!(reg & PCI_ERR_COR_BAD_DLLP))
		return;
	reg &= ~PCI_ERR_COR_BAD_DLLP;
	pci_write_config_dword(dev, pos + PCI_ERR_COR_MASK, reg);
}

static int hpc_power_off_slot(struct slot * slot)
{
	struct controller *ctrl = slot->ctrl;
	u16 slot_cmd;
	u16 cmd_mask;
	int retval = 0;
	int changed;

	dbg("%s: slot->hp_slot %x\n", __func__, slot->hp_slot);

	/*
	 * Set Bad DLLP Mask bit in Correctable Error Mask
	 * Register. This is the workaround against Bad DLLP error
	 * that sometimes happens during turning power off the slot
	 * which conforms to PCI Express 1.0a spec.
	 */
	changed = pcie_mask_bad_dllp(ctrl);

	slot_cmd = POWER_OFF;
	cmd_mask = PWR_CTRL;
	/*
	 * If we get MRL or presence detect interrupts now, the isr
	 * will notice the sticky power-fault bit too and issue power
	 * indicator change commands. This will lead to an endless loop
	 * of command completions, since the power-fault bit remains on
	 * till the slot is powered on again.
	 */
	if (!pciehp_poll_mode) {
		slot_cmd &= ~(PWR_FAULT_DETECT_ENABLE | MRL_DETECT_ENABLE |
			      PRSN_DETECT_ENABLE);
		cmd_mask |= (PWR_FAULT_DETECT_ENABLE | MRL_DETECT_ENABLE |
			     PRSN_DETECT_ENABLE);
	}

	retval = pcie_write_cmd(ctrl, slot_cmd, cmd_mask);
	if (retval) {
		err("%s: Write command failed!\n", __func__);
		retval = -1;
		goto out;
	}
	dbg("%s: SLOTCTRL %x write cmd %x\n",
	    __func__, ctrl->cap_base + SLOTCTRL, slot_cmd);

	/*
	 * After turning power off, we must wait for at least 1 second
	 * before taking any action that relies on power having been
	 * removed from the slot/adapter.
	 */
	msleep(1000);
 out:
	if (changed)
		pcie_unmask_bad_dllp(ctrl);

	return retval;
}

static irqreturn_t pcie_isr(int irq, void *dev_id)
{
	struct controller *ctrl = (struct controller *)dev_id;
	u16 detected, intr_loc;

	/*
	 * In order to guarantee that all interrupt events are
	 * serviced, we need to re-inspect Slot Status register after
	 * clearing what is presumed to be the last pending interrupt.
	 */
	intr_loc = 0;
	do {
		if (pciehp_readw(ctrl, SLOTSTATUS, &detected)) {
			err("%s: Cannot read SLOTSTATUS\n", __func__);
			return IRQ_NONE;
		}

		detected &= (ATTN_BUTTN_PRESSED | PWR_FAULT_DETECTED |
			     MRL_SENS_CHANGED | PRSN_DETECT_CHANGED |
			     CMD_COMPLETED);
		intr_loc |= detected;
		if (!intr_loc)
			return IRQ_NONE;
		if (pciehp_writew(ctrl, SLOTSTATUS, detected)) {
			err("%s: Cannot write to SLOTSTATUS\n", __func__);
			return IRQ_NONE;
		}
	} while (detected);

	dbg("%s: intr_loc %x\n", __FUNCTION__, intr_loc);

	/* Check Command Complete Interrupt Pending */
	if (intr_loc & CMD_COMPLETED) {
		ctrl->cmd_busy = 0;
		smp_mb();
		wake_up_interruptible(&ctrl->queue);
	}

	/* Check MRL Sensor Changed */
	if (intr_loc & MRL_SENS_CHANGED)
		pciehp_handle_switch_change(0, ctrl);

	/* Check Attention Button Pressed */
	if (intr_loc & ATTN_BUTTN_PRESSED)
		pciehp_handle_attention_button(0, ctrl);

	/* Check Presence Detect Changed */
	if (intr_loc & PRSN_DETECT_CHANGED)
		pciehp_handle_presence_change(0, ctrl);

	/* Check Power Fault Detected */
	if (intr_loc & PWR_FAULT_DETECTED)
		pciehp_handle_power_fault(0, ctrl);

	return IRQ_HANDLED;
}

static int hpc_get_max_lnk_speed(struct slot *slot, enum pci_bus_speed *value)
{
	struct controller *ctrl = slot->ctrl;
	enum pcie_link_speed lnk_speed;
	u32	lnk_cap;
	int retval = 0;

	retval = pciehp_readl(ctrl, LNKCAP, &lnk_cap);
	if (retval) {
		err("%s: Cannot read LNKCAP register\n", __func__);
		return retval;
	}

	switch (lnk_cap & 0x000F) {
	case 1:
		lnk_speed = PCIE_2PT5GB;
		break;
	default:
		lnk_speed = PCIE_LNK_SPEED_UNKNOWN;
		break;
	}

	*value = lnk_speed;
	dbg("Max link speed = %d\n", lnk_speed);

	return retval;
}

static int hpc_get_max_lnk_width(struct slot *slot,
				 enum pcie_link_width *value)
{
	struct controller *ctrl = slot->ctrl;
	enum pcie_link_width lnk_wdth;
	u32	lnk_cap;
	int retval = 0;

	retval = pciehp_readl(ctrl, LNKCAP, &lnk_cap);
	if (retval) {
		err("%s: Cannot read LNKCAP register\n", __func__);
		return retval;
	}

	switch ((lnk_cap & 0x03F0) >> 4){
	case 0:
		lnk_wdth = PCIE_LNK_WIDTH_RESRV;
		break;
	case 1:
		lnk_wdth = PCIE_LNK_X1;
		break;
	case 2:
		lnk_wdth = PCIE_LNK_X2;
		break;
	case 4:
		lnk_wdth = PCIE_LNK_X4;
		break;
	case 8:
		lnk_wdth = PCIE_LNK_X8;
		break;
	case 12:
		lnk_wdth = PCIE_LNK_X12;
		break;
	case 16:
		lnk_wdth = PCIE_LNK_X16;
		break;
	case 32:
		lnk_wdth = PCIE_LNK_X32;
		break;
	default:
		lnk_wdth = PCIE_LNK_WIDTH_UNKNOWN;
		break;
	}

	*value = lnk_wdth;
	dbg("Max link width = %d\n", lnk_wdth);

	return retval;
}

static int hpc_get_cur_lnk_speed(struct slot *slot, enum pci_bus_speed *value)
{
	struct controller *ctrl = slot->ctrl;
	enum pcie_link_speed lnk_speed = PCI_SPEED_UNKNOWN;
	int retval = 0;
	u16 lnk_status;

	retval = pciehp_readw(ctrl, LNKSTATUS, &lnk_status);
	if (retval) {
		err("%s: Cannot read LNKSTATUS register\n", __func__);
		return retval;
	}

	switch (lnk_status & 0x0F) {
	case 1:
		lnk_speed = PCIE_2PT5GB;
		break;
	default:
		lnk_speed = PCIE_LNK_SPEED_UNKNOWN;
		break;
	}

	*value = lnk_speed;
	dbg("Current link speed = %d\n", lnk_speed);

	return retval;
}

static int hpc_get_cur_lnk_width(struct slot *slot,
				 enum pcie_link_width *value)
{
	struct controller *ctrl = slot->ctrl;
	enum pcie_link_width lnk_wdth = PCIE_LNK_WIDTH_UNKNOWN;
	int retval = 0;
	u16 lnk_status;

	retval = pciehp_readw(ctrl, LNKSTATUS, &lnk_status);
	if (retval) {
		err("%s: Cannot read LNKSTATUS register\n", __func__);
		return retval;
	}

	switch ((lnk_status & 0x03F0) >> 4){
	case 0:
		lnk_wdth = PCIE_LNK_WIDTH_RESRV;
		break;
	case 1:
		lnk_wdth = PCIE_LNK_X1;
		break;
	case 2:
		lnk_wdth = PCIE_LNK_X2;
		break;
	case 4:
		lnk_wdth = PCIE_LNK_X4;
		break;
	case 8:
		lnk_wdth = PCIE_LNK_X8;
		break;
	case 12:
		lnk_wdth = PCIE_LNK_X12;
		break;
	case 16:
		lnk_wdth = PCIE_LNK_X16;
		break;
	case 32:
		lnk_wdth = PCIE_LNK_X32;
		break;
	default:
		lnk_wdth = PCIE_LNK_WIDTH_UNKNOWN;
		break;
	}

	*value = lnk_wdth;
	dbg("Current link width = %d\n", lnk_wdth);

	return retval;
}

static struct hpc_ops pciehp_hpc_ops = {
	.power_on_slot			= hpc_power_on_slot,
	.power_off_slot			= hpc_power_off_slot,
	.set_attention_status		= hpc_set_attention_status,
	.get_power_status		= hpc_get_power_status,
	.get_attention_status		= hpc_get_attention_status,
	.get_latch_status		= hpc_get_latch_status,
	.get_adapter_status		= hpc_get_adapter_status,
	.get_emi_status			= hpc_get_emi_status,
	.toggle_emi			= hpc_toggle_emi,

	.get_max_bus_speed		= hpc_get_max_lnk_speed,
	.get_cur_bus_speed		= hpc_get_cur_lnk_speed,
	.get_max_lnk_width		= hpc_get_max_lnk_width,
	.get_cur_lnk_width		= hpc_get_cur_lnk_width,

	.query_power_fault		= hpc_query_power_fault,
	.green_led_on			= hpc_set_green_led_on,
	.green_led_off			= hpc_set_green_led_off,
	.green_led_blink		= hpc_set_green_led_blink,

	.release_ctlr			= hpc_release_ctlr,
	.check_lnk_status		= hpc_check_lnk_status,
};

#ifdef CONFIG_ACPI
static int pciehp_acpi_get_hp_hw_control_from_firmware(struct pci_dev *dev)
{
	acpi_status status;
	acpi_handle chandle, handle = DEVICE_ACPI_HANDLE(&(dev->dev));
	struct pci_dev *pdev = dev;
	struct pci_bus *parent;
	struct acpi_buffer string = { ACPI_ALLOCATE_BUFFER, NULL };

	/*
	 * Per PCI firmware specification, we should run the ACPI _OSC
	 * method to get control of hotplug hardware before using it.
	 * If an _OSC is missing, we look for an OSHP to do the same thing.
	 * To handle different BIOS behavior, we look for _OSC and OSHP
	 * within the scope of the hotplug controller and its parents, upto
	 * the host bridge under which this controller exists.
	 */
	while (!handle) {
		/*
		 * This hotplug controller was not listed in the ACPI name
		 * space at all. Try to get acpi handle of parent pci bus.
		 */
		if (!pdev || !pdev->bus->parent)
			break;
		parent = pdev->bus->parent;
		dbg("Could not find %s in acpi namespace, trying parent\n",
				pci_name(pdev));
		if (!parent->self)
			/* Parent must be a host bridge */
			handle = acpi_get_pci_rootbridge_handle(
					pci_domain_nr(parent),
					parent->number);
		else
			handle = DEVICE_ACPI_HANDLE(
					&(parent->self->dev));
		pdev = parent->self;
	}

	while (handle) {
		acpi_get_name(handle, ACPI_FULL_PATHNAME, &string);
		dbg("Trying to get hotplug control for %s \n",
			(char *)string.pointer);
		status = pci_osc_control_set(handle,
				OSC_PCI_EXPRESS_CAP_STRUCTURE_CONTROL |
				OSC_PCI_EXPRESS_NATIVE_HP_CONTROL);
		if (status == AE_NOT_FOUND)
			status = acpi_run_oshp(handle);
		if (ACPI_SUCCESS(status)) {
			dbg("Gained control for hotplug HW for pci %s (%s)\n",
				pci_name(dev), (char *)string.pointer);
			kfree(string.pointer);
			return 0;
		}
		if (acpi_root_bridge(handle))
			break;
		chandle = handle;
		status = acpi_get_parent(chandle, &handle);
		if (ACPI_FAILURE(status))
			break;
	}

	dbg("Cannot get control of hotplug hardware for pci %s\n",
			pci_name(dev));

	kfree(string.pointer);
	return -1;
}
#endif

static int pcie_init_hardware_part1(struct controller *ctrl,
				    struct pcie_device *dev)
{
	/* Mask Hot-plug Interrupt Enable */
	if (pcie_write_cmd(ctrl, 0, HP_INTR_ENABLE | CMD_CMPL_INTR_ENABLE)) {
		err("%s: Cannot mask hotplug interrupt enable\n", __func__);
		return -1;
	}
	return 0;
}

int pcie_init_hardware_part2(struct controller *ctrl, struct pcie_device *dev)
{
	u16 cmd, mask;

	/*
	 * We need to clear all events before enabling hotplug interrupt
	 * notification mechanism in order for hotplug controler to
	 * generate interrupts.
	 */
	if (pciehp_writew(ctrl, SLOTSTATUS, 0x1f)) {
		err("%s: Cannot write to SLOTSTATUS register\n", __FUNCTION__);
		return -1;
	}

	cmd = PRSN_DETECT_ENABLE;
	if (ATTN_BUTTN(ctrl))
		cmd |= ATTN_BUTTN_ENABLE;
	if (POWER_CTRL(ctrl))
		cmd |= PWR_FAULT_DETECT_ENABLE;
	if (MRL_SENS(ctrl))
		cmd |= MRL_DETECT_ENABLE;
	if (!pciehp_poll_mode)
		cmd |= HP_INTR_ENABLE;

	mask = PRSN_DETECT_ENABLE | ATTN_BUTTN_ENABLE |
		PWR_FAULT_DETECT_ENABLE | MRL_DETECT_ENABLE | HP_INTR_ENABLE;

	if (pcie_write_cmd(ctrl, cmd, mask)) {
		err("%s: Cannot enable software notification\n", __func__);
		goto abort;
	}

	if (pciehp_force)
		dbg("Bypassing BIOS check for pciehp use on %s\n",
				pci_name(ctrl->pci_dev));
	else if (pciehp_get_hp_hw_control_from_firmware(ctrl->pci_dev))
		goto abort_disable_intr;

	return 0;

	/* We end up here for the many possible ways to fail this API. */
abort_disable_intr:
	if (pcie_write_cmd(ctrl, 0, HP_INTR_ENABLE))
		err("%s : disabling interrupts failed\n", __func__);
abort:
	return -1;
}

static inline void dbg_ctrl(struct controller *ctrl)
{
	int i;
	u16 reg16;
	struct pci_dev *pdev = ctrl->pci_dev;

	if (!pciehp_debug)
		return;

	dbg("Hotplug Controller:\n");
	dbg("  Seg/Bus/Dev/Func/IRQ : %s IRQ %d\n", pci_name(pdev), pdev->irq);
	dbg("  Vendor ID            : 0x%04x\n", pdev->vendor);
	dbg("  Device ID            : 0x%04x\n", pdev->device);
	dbg("  Subsystem ID         : 0x%04x\n", pdev->subsystem_device);
	dbg("  Subsystem Vendor ID  : 0x%04x\n", pdev->subsystem_vendor);
	dbg("  PCIe Cap offset      : 0x%02x\n", ctrl->cap_base);
	for (i = 0; i < DEVICE_COUNT_RESOURCE; i++) {
		if (!pci_resource_len(pdev, i))
			continue;
		dbg("  PCI resource [%d]     : 0x%llx@0x%llx\n", i,
		    (unsigned long long)pci_resource_len(pdev, i),
		    (unsigned long long)pci_resource_start(pdev, i));
	}
	dbg("Slot Capabilities      : 0x%08x\n", ctrl->slot_cap);
	dbg("  Physical Slot Number : %d\n", ctrl->first_slot);
	dbg("  Attention Button     : %3s\n", ATTN_BUTTN(ctrl) ? "yes" : "no");
	dbg("  Power Controller     : %3s\n", POWER_CTRL(ctrl) ? "yes" : "no");
	dbg("  MRL Sensor           : %3s\n", MRL_SENS(ctrl)   ? "yes" : "no");
	dbg("  Attention Indicator  : %3s\n", ATTN_LED(ctrl)   ? "yes" : "no");
	dbg("  Power Indicator      : %3s\n", PWR_LED(ctrl)    ? "yes" : "no");
	dbg("  Hot-Plug Surprise    : %3s\n", HP_SUPR_RM(ctrl) ? "yes" : "no");
	dbg("  EMI Present          : %3s\n", EMI(ctrl)        ? "yes" : "no");
	pciehp_readw(ctrl, SLOTSTATUS, &reg16);
	dbg("Slot Status            : 0x%04x\n", reg16);
	pciehp_readw(ctrl, SLOTSTATUS, &reg16);
	dbg("Slot Control           : 0x%04x\n", reg16);
}

int pcie_init(struct controller *ctrl, struct pcie_device *dev)
{
	u32 slot_cap;
	struct pci_dev *pdev = dev->port;

	ctrl->pci_dev = pdev;
	ctrl->cap_base = pci_find_capability(pdev, PCI_CAP_ID_EXP);
	if (!ctrl->cap_base) {
		err("%s: Cannot find PCI Express capability\n", __func__);
		goto abort;
	}
	if (pciehp_readl(ctrl, SLOTCAP, &slot_cap)) {
		err("%s: Cannot read SLOTCAP register\n", __func__);
		goto abort;
	}

	ctrl->slot_cap = slot_cap;
	ctrl->first_slot = slot_cap >> 19;
	ctrl->slot_device_offset = 0;
	ctrl->num_slots = 1;
	ctrl->hpc_ops = &pciehp_hpc_ops;
	mutex_init(&ctrl->crit_sect);
	mutex_init(&ctrl->ctrl_lock);
	init_waitqueue_head(&ctrl->queue);
	dbg_ctrl(ctrl);

	info("HPC vendor_id %x device_id %x ss_vid %x ss_did %x\n",
	     pdev->vendor, pdev->device,
	     pdev->subsystem_vendor, pdev->subsystem_device);

	if (pcie_init_hardware_part1(ctrl, dev))
		goto abort;

	if (pciehp_request_irq(ctrl))
		goto abort;

	/*
	 * If this is the first controller to be initialized,
	 * initialize the pciehp work queue
	 */
	if (atomic_add_return(1, &pciehp_num_controllers) == 1) {
		pciehp_wq = create_singlethread_workqueue("pciehpd");
		if (!pciehp_wq) {
			goto abort_free_irq;
		}
	}

	if (pcie_init_hardware_part2(ctrl, dev))
		goto abort_free_irq;

	return 0;

abort_free_irq:
	pciehp_free_irq(ctrl);
abort:
	return -1;
}
OpenPOWER on IntegriCloud