summaryrefslogtreecommitdiff
path: root/util/flashrom/chipset_enable.c
blob: d2ae21279a2867c685c4d8605ab522a2d304f3ed (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
/*
 * This file is part of the flashrom project.
 *
 * Copyright (C) 2000 Silicon Integrated System Corporation
 * Copyright (C) 2005-2007 coresystems GmbH <stepan@coresystems.de>
 * Copyright (C) 2006 Uwe Hermann <uwe@hermann-uwe.de>
 *
 * 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; version 2 of the License.
 *
 * 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.  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
 */

/*
 * Contains the chipset specific flash enables.
 */

#define _LARGEFILE64_SOURCE

#include <stdio.h>
#include <pci/pci.h>
#include <stdlib.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <sys/mman.h>
#include <fcntl.h>
#include <unistd.h>
#include "flash.h"

unsigned long flashbase = 0;

/**
 * flashrom defaults to LPC flash devices. If a known SPI controller is found
 * and the SPI strappings are set, this will be overwritten by the probing code.
 *
 * Eventually, this will become an array when multiple flash support works.
 */

flashbus_t flashbus = BUS_TYPE_LPC;
void *spibar = NULL;

extern int ichspi_lock;

static int enable_flash_ali_m1533(struct pci_dev *dev, const char *name)
{
	uint8_t tmp;

	/*
	 * ROM Write enable, 0xFFFC0000-0xFFFDFFFF and
	 * 0xFFFE0000-0xFFFFFFFF ROM select enable.
	 */
	tmp = pci_read_byte(dev, 0x47);
	tmp |= 0x46;
	pci_write_byte(dev, 0x47, tmp);

	return 0;
}

static int enable_flash_sis630(struct pci_dev *dev, const char *name)
{
	uint8_t b;

	/* Enable 0xFFF8000~0xFFFF0000 decoding on SiS 540/630. */
	b = pci_read_byte(dev, 0x40);
	pci_write_byte(dev, 0x40, b | 0xb);

	/* Flash write enable on SiS 540/630. */
	b = pci_read_byte(dev, 0x45);
	pci_write_byte(dev, 0x45, b | 0x40);

	/* The same thing on SiS 950 Super I/O side... */

	/* First probe for Super I/O on config port 0x2e. */
	OUTB(0x87, 0x2e);
	OUTB(0x01, 0x2e);
	OUTB(0x55, 0x2e);
	OUTB(0x55, 0x2e);

	if (INB(0x2f) != 0x87) {
		/* If that failed, try config port 0x4e. */
		OUTB(0x87, 0x4e);
		OUTB(0x01, 0x4e);
		OUTB(0x55, 0x4e);
		OUTB(0xaa, 0x4e);
		if (INB(0x4f) != 0x87) {
			printf("Can not access SiS 950\n");
			return -1;
		}
		OUTB(0x24, 0x4e);
		b = INB(0x4f) | 0xfc;
		OUTB(0x24, 0x4e);
		OUTB(b, 0x4f);
		OUTB(0x02, 0x4e);
		OUTB(0x02, 0x4f);
	}

	OUTB(0x24, 0x2e);
	printf("2f is %#x\n", INB(0x2f));
	b = INB(0x2f) | 0xfc;
	OUTB(0x24, 0x2e);
	OUTB(b, 0x2f);

	OUTB(0x02, 0x2e);
	OUTB(0x02, 0x2f);

	return 0;
}

/* Datasheet:
 *   - Name: 82371AB PCI-TO-ISA / IDE XCELERATOR (PIIX4)
 *   - URL: http://www.intel.com/design/intarch/datashts/290562.htm
 *   - PDF: http://www.intel.com/design/intarch/datashts/29056201.pdf
 *   - Order Number: 290562-001
 */
static int enable_flash_piix4(struct pci_dev *dev, const char *name)
{
	uint16_t old, new;
	uint16_t xbcs = 0x4e;	/* X-Bus Chip Select register. */

	old = pci_read_word(dev, xbcs);

	/* Set bit 9: 1-Meg Extended BIOS Enable (PCI master accesses to
	 *            FFF00000-FFF7FFFF are forwarded to ISA).
	 *            Note: This bit is reserved on PIIX/PIIX3/MPIIX.
	 * Set bit 7: Extended BIOS Enable (PCI master accesses to
	 *            FFF80000-FFFDFFFF are forwarded to ISA).
	 * Set bit 6: Lower BIOS Enable (PCI master, or ISA master accesses to
	 *            the lower 64-Kbyte BIOS block (E0000-EFFFF) at the top
	 *            of 1 Mbyte, or the aliases at the top of 4 Gbyte
	 *            (FFFE0000-FFFEFFFF) result in the generation of BIOSCS#.
	 * Note: Accesses to FFFF0000-FFFFFFFF are always forwarded to ISA.
	 * Set bit 2: BIOSCS# Write Enable (1=enable, 0=disable).
	 */
	if (dev->device_id == 0x122e || dev->device_id == 0x7000
	    || dev->device_id == 0x1234)
		new = old | 0x00c4; /* PIIX/PIIX3/MPIIX: Bit 9 is reserved. */
	else
		new = old | 0x02c4;

	if (new == old)
		return 0;

	pci_write_word(dev, xbcs, new);

	if (pci_read_word(dev, xbcs) != new) {
		printf("tried to set 0x%x to 0x%x on %s failed (WARNING ONLY)\n", xbcs, new, name);
		return -1;
	}

	return 0;
}

/*
 * See ie. page 375 of "Intel I/O Controller Hub 7 (ICH7) Family Datasheet"
 * http://download.intel.com/design/chipsets/datashts/30701303.pdf
 */
static int enable_flash_ich(struct pci_dev *dev, const char *name,
			    int bios_cntl)
{
	uint8_t old, new;

	/*
	 * Note: the ICH0-ICH5 BIOS_CNTL register is actually 16 bit wide, but
	 * just treating it as 8 bit wide seems to work fine in practice.
	 */
	old = pci_read_byte(dev, bios_cntl);

	printf_debug("\nBIOS Lock Enable: %sabled, ",
		     (old & (1 << 1)) ? "en" : "dis");
	printf_debug("BIOS Write Enable: %sabled, ",
		     (old & (1 << 0)) ? "en" : "dis");
	printf_debug("BIOS_CNTL is 0x%x\n", old);

	new = old | 1;

	if (new == old)
		return 0;

	pci_write_byte(dev, bios_cntl, new);

	if (pci_read_byte(dev, bios_cntl) != new) {
		printf("tried to set 0x%x to 0x%x on %s failed (WARNING ONLY)\n", bios_cntl, new, name);
		return -1;
	}

	return 0;
}

static int enable_flash_ich_4e(struct pci_dev *dev, const char *name)
{
	return enable_flash_ich(dev, name, 0x4e);
}

static int enable_flash_ich_dc(struct pci_dev *dev, const char *name)
{
	return enable_flash_ich(dev, name, 0xdc);
}

#define ICH_STRAP_RSVD 0x00
#define ICH_STRAP_SPI  0x01
#define ICH_STRAP_PCI  0x02
#define ICH_STRAP_LPC  0x03

static int enable_flash_vt8237s_spi(struct pci_dev *dev, const char *name)
{
	uint32_t mmio_base;

	mmio_base = (pci_read_long(dev, 0xbc)) << 8;
	printf_debug("MMIO base at = 0x%x\n", mmio_base);
	spibar = mmap(NULL, 0x70, PROT_READ | PROT_WRITE, MAP_SHARED,
		      fd_mem, mmio_base);

	if (spibar == MAP_FAILED) {
		perror("Can't mmap memory using " MEM_DEV);
		exit(1);
	}

	printf_debug("0x6c: 0x%04x     (CLOCK/DEBUG)\n",
		     *(uint16_t *) (spibar + 0x6c));

	flashbus = BUS_TYPE_VIA_SPI;

	return 0;
}

static int enable_flash_ich_dc_spi(struct pci_dev *dev, const char *name,
				   int ich_generation)
{
	int ret, i;
	uint8_t old, new, bbs, buc;
	uint16_t spibar_offset, tmp2;
	uint32_t tmp, gcs;
	void *rcrb;
	//TODO: These names are incorrect for EP80579. For that, the solution would look like the commented line
	//static const char *straps_names[] = {"SPI", "reserved", "reserved", "LPC" };
	static const char *straps_names[] = { "reserved", "SPI", "PCI", "LPC" };

	/* Enable Flash Writes */
	ret = enable_flash_ich_dc(dev, name);

	/* Get physical address of Root Complex Register Block */
	tmp = pci_read_long(dev, 0xf0) & 0xffffc000;
	printf_debug("\nRoot Complex Register Block address = 0x%x\n", tmp);

	/* Map RCBA to virtual memory */
	rcrb = mmap(0, 0x4000, PROT_READ | PROT_WRITE, MAP_SHARED, fd_mem,
		    (off_t) tmp);
	if (rcrb == MAP_FAILED) {
		perror("Can't mmap memory using " MEM_DEV);
		exit(1);
	}

	gcs = *(volatile uint32_t *)(rcrb + 0x3410);
	printf_debug("GCS = 0x%x: ", gcs);
	printf_debug("BIOS Interface Lock-Down: %sabled, ",
		     (gcs & 0x1) ? "en" : "dis");
	bbs = (gcs >> 10) & 0x3;
	printf_debug("BOOT BIOS Straps: 0x%x (%s)\n", bbs, straps_names[bbs]);

	buc = *(volatile uint8_t *)(rcrb + 0x3414);
	printf_debug("Top Swap : %s\n",
		     (buc & 1) ? "enabled (A16 inverted)" : "not enabled");

	/* It seems the ICH7 does not support SPI and LPC chips at the same
	 * time. At least not with our current code. So we prevent searching
	 * on ICH7 when the southbridge is strapped to LPC
	 */

	if (ich_generation == 7 && bbs == ICH_STRAP_LPC) {
		/* No further SPI initialization required */
		return ret;
	}

	switch (ich_generation) {
	case 7:
		flashbus = BUS_TYPE_ICH7_SPI;
		spibar_offset = 0x3020;
		break;
	case 8:
		flashbus = BUS_TYPE_ICH9_SPI;
		spibar_offset = 0x3020;
		break;
	case 9:
	case 10:
	default:		/* Future version might behave the same */
		flashbus = BUS_TYPE_ICH9_SPI;
		spibar_offset = 0x3800;
		break;
	}

	/* SPIBAR is at RCRB+0x3020 for ICH[78] and RCRB+0x3800 for ICH9. */
	printf_debug("SPIBAR = 0x%x + 0x%04x\n", tmp, spibar_offset);

	/* Assign Virtual Address */
	spibar = rcrb + spibar_offset;

	switch (flashbus) {
	case BUS_TYPE_ICH7_SPI:
		printf_debug("0x00: 0x%04x     (SPIS)\n",
			     *(uint16_t *) (spibar + 0));
		printf_debug("0x02: 0x%04x     (SPIC)\n",
			     *(uint16_t *) (spibar + 2));
		printf_debug("0x04: 0x%08x (SPIA)\n",
			     *(uint32_t *) (spibar + 4));
		for (i = 0; i < 8; i++) {
			int offs;
			offs = 8 + (i * 8);
			printf_debug("0x%02x: 0x%08x (SPID%d)\n", offs,
				     *(uint32_t *) (spibar + offs), i);
			printf_debug("0x%02x: 0x%08x (SPID%d+4)\n", offs + 4,
				     *(uint32_t *) (spibar + offs + 4), i);
		}
		printf_debug("0x50: 0x%08x (BBAR)\n",
			     *(uint32_t *) (spibar + 0x50));
		printf_debug("0x54: 0x%04x     (PREOP)\n",
			     *(uint16_t *) (spibar + 0x54));
		printf_debug("0x56: 0x%04x     (OPTYPE)\n",
			     *(uint16_t *) (spibar + 0x56));
		printf_debug("0x58: 0x%08x (OPMENU)\n",
			     *(uint32_t *) (spibar + 0x58));
		printf_debug("0x5c: 0x%08x (OPMENU+4)\n",
			     *(uint32_t *) (spibar + 0x5c));
		for (i = 0; i < 4; i++) {
			int offs;
			offs = 0x60 + (i * 4);
			printf_debug("0x%02x: 0x%08x (PBR%d)\n", offs,
				     *(uint32_t *) (spibar + offs), i);
		}
		printf_debug("\n");
		if ((*(uint16_t *) spibar) & (1 << 15)) {
			printf("WARNING: SPI Configuration Lockdown activated.\n");
			ichspi_lock = 1;
		}
		break;
	case BUS_TYPE_ICH9_SPI:
		tmp2 = *(uint16_t *) (spibar + 0);
		printf_debug("0x00: 0x%04x (HSFS)\n", tmp2);
		printf_debug("FLOCKDN %i, ", (tmp >> 15 & 1));
		printf_debug("FDV %i, ", (tmp >> 14) & 1);
		printf_debug("FDOPSS %i, ", (tmp >> 13) & 1);
		printf_debug("SCIP %i, ", (tmp >> 5) & 1);
		printf_debug("BERASE %i, ", (tmp >> 3) & 3);
		printf_debug("AEL %i, ", (tmp >> 2) & 1);
		printf_debug("FCERR %i, ", (tmp >> 1) & 1);
		printf_debug("FDONE %i\n", (tmp >> 0) & 1);

		tmp = *(uint32_t *) (spibar + 0x50);
		printf_debug("0x50: 0x%08x (FRAP)\n", tmp);
		printf_debug("BMWAG %i, ", (tmp >> 24) & 0xff);
		printf_debug("BMRAG %i, ", (tmp >> 16) & 0xff);
		printf_debug("BRWA %i, ", (tmp >> 8) & 0xff);
		printf_debug("BRRA %i\n", (tmp >> 0) & 0xff);

		printf_debug("0x54: 0x%08x (FREG0)\n",
			     *(uint32_t *) (spibar + 0x54));
		printf_debug("0x58: 0x%08x (FREG1)\n",
			     *(uint32_t *) (spibar + 0x58));
		printf_debug("0x5C: 0x%08x (FREG2)\n",
			     *(uint32_t *) (spibar + 0x5C));
		printf_debug("0x60: 0x%08x (FREG3)\n",
			     *(uint32_t *) (spibar + 0x60));
		printf_debug("0x64: 0x%08x (FREG4)\n",
			     *(uint32_t *) (spibar + 0x64));
		printf_debug("0x74: 0x%08x (PR0)\n",
			     *(uint32_t *) (spibar + 0x74));
		printf_debug("0x78: 0x%08x (PR1)\n",
			     *(uint32_t *) (spibar + 0x78));
		printf_debug("0x7C: 0x%08x (PR2)\n",
			     *(uint32_t *) (spibar + 0x7C));
		printf_debug("0x80: 0x%08x (PR3)\n",
			     *(uint32_t *) (spibar + 0x80));
		printf_debug("0x84: 0x%08x (PR4)\n",
			     *(uint32_t *) (spibar + 0x84));
		/* printf_debug("0xA0: 0x%08x (BBAR)\n",
			     *(uint32_t *) (spibar + 0xA0)); ICH10 only? */
		printf_debug("0xB0: 0x%08x (FDOC)\n",
			     *(uint32_t *) (spibar + 0xB0));
		break;
	default:
		/* Nothing */
		break;
	}

	old = pci_read_byte(dev, 0xdc);
	printf_debug("SPI Read Configuration: ");
	new = (old >> 2) & 0x3;
	switch (new) {
	case 0:
	case 1:
	case 2:
		printf_debug("prefetching %sabled, caching %sabled, ",
			     (new & 0x2) ? "en" : "dis",
			     (new & 0x1) ? "dis" : "en");
		break;
	default:
		printf_debug("invalid prefetching/caching settings, ");
		break;
	}

	return ret;
}

static int enable_flash_ich7(struct pci_dev *dev, const char *name)
{
	return enable_flash_ich_dc_spi(dev, name, 7);
}

static int enable_flash_ich8(struct pci_dev *dev, const char *name)
{
	return enable_flash_ich_dc_spi(dev, name, 8);
}

static int enable_flash_ich9(struct pci_dev *dev, const char *name)
{
	return enable_flash_ich_dc_spi(dev, name, 9);
}

static int enable_flash_ich10(struct pci_dev *dev, const char *name)
{
	return enable_flash_ich_dc_spi(dev, name, 10);
}

static int enable_flash_vt823x(struct pci_dev *dev, const char *name)
{
	uint8_t val;

	/* enable ROM decode range (1MB) FFC00000 - FFFFFFFF */
	pci_write_byte(dev, 0x41, 0x7f);

	/* ROM write enable */
	val = pci_read_byte(dev, 0x40);
	val |= 0x10;
	pci_write_byte(dev, 0x40, val);

	if (pci_read_byte(dev, 0x40) != val) {
		printf("\nWARNING: Failed to enable ROM Write on \"%s\"\n",
		       name);
		return -1;
	}

	return 0;
}

static int enable_flash_cs5530(struct pci_dev *dev, const char *name)
{
	uint8_t reg8;

#define DECODE_CONTROL_REG2		0x5b	/* F0 index 0x5b */
#define ROM_AT_LOGIC_CONTROL_REG	0x52	/* F0 index 0x52 */

#define LOWER_ROM_ADDRESS_RANGE		(1 << 0)
#define ROM_WRITE_ENABLE		(1 << 1)
#define UPPER_ROM_ADDRESS_RANGE		(1 << 2)
#define BIOS_ROM_POSITIVE_DECODE	(1 << 5)

	/* Decode 0x000E0000-0x000FFFFF (128 KB), not just 64 KB, and
	 * decode 0xFF000000-0xFFFFFFFF (16 MB), not just 256 KB.
	 * Make the configured ROM areas writable.
	 */
	reg8 = pci_read_byte(dev, ROM_AT_LOGIC_CONTROL_REG);
	reg8 |= LOWER_ROM_ADDRESS_RANGE;
	reg8 |= UPPER_ROM_ADDRESS_RANGE;
	reg8 |= ROM_WRITE_ENABLE;
	pci_write_byte(dev, ROM_AT_LOGIC_CONTROL_REG, reg8);

	/* Set positive decode on ROM. */
	reg8 = pci_read_byte(dev, DECODE_CONTROL_REG2);
	reg8 |= BIOS_ROM_POSITIVE_DECODE;
	pci_write_byte(dev, DECODE_CONTROL_REG2, reg8);

	return 0;
}

/**
 * Geode systems write protect the BIOS via RCONFs (cache settings similar
 * to MTRRs). To unlock, change MSR 0x1808 top byte to 0x22. Reading and
 * writing to MSRs, however requires instructions rdmsr/wrmsr, which are
 * ring0 privileged instructions so only the kernel can do the read/write.
 * This function, therefore, requires that the msr kernel module be loaded
 * to access these instructions from user space using device /dev/cpu/0/msr.
 *
 * This hard-coded location could have potential problems on SMP machines
 * since it assumes cpu0, but it is safe on the Geode which is not SMP.
 *
 * Geode systems also write protect the NOR flash chip itself via MSR_NORF_CTL.
 * To enable write to NOR Boot flash for the benefit of systems that have such
 * a setup, raise MSR 0x51400018 WE_CS3 (write enable Boot Flash Chip Select).
 *
 * This is probably not portable beyond Linux.
 */
static int enable_flash_cs5536(struct pci_dev *dev, const char *name)
{
#define MSR_RCONF_DEFAULT	0x1808
#define MSR_NORF_CTL		0x51400018

	int fd_msr;
	unsigned char buf[8];

	fd_msr = open("/dev/cpu/0/msr", O_RDWR);
	if (!fd_msr) {
		perror("open msr");
		return -1;
	}

	if (lseek64(fd_msr, (off64_t) MSR_RCONF_DEFAULT, SEEK_SET) == -1) {
		perror("lseek64");
		printf("Cannot operate on MSR. Did you run 'modprobe msr'?\n");
		close(fd_msr);
		return -1;
	}

	if (read(fd_msr, buf, 8) != 8) {
		perror("read msr");
		close(fd_msr);
		return -1;
	}

	if (buf[7] != 0x22) {
		buf[7] &= 0xfb;
		if (lseek64(fd_msr, (off64_t) MSR_RCONF_DEFAULT,
			    SEEK_SET) == -1) {
			perror("lseek64");
			close(fd_msr);
			return -1;
		}

		if (write(fd_msr, buf, 8) < 0) {
			perror("msr write");
			close(fd_msr);
			return -1;
		}
	}

	if (lseek64(fd_msr, (off64_t) MSR_NORF_CTL, SEEK_SET) == -1) {
		perror("lseek64");
		close(fd_msr);
		return -1;
	}

	if (read(fd_msr, buf, 8) != 8) {
		perror("read msr");
		close(fd_msr);
		return -1;
	}

	/* Raise WE_CS3 bit. */
	buf[0] |= 0x08;

	if (lseek64(fd_msr, (off64_t) MSR_NORF_CTL, SEEK_SET) == -1) {
		perror("lseek64");
		close(fd_msr);
		return -1;
	}
	if (write(fd_msr, buf, 8) < 0) {
		perror("msr write");
		close(fd_msr);
		return -1;
	}

	close(fd_msr);

#undef MSR_RCONF_DEFAULT
#undef MSR_NORF_CTL
	return 0;
}

static int enable_flash_sc1100(struct pci_dev *dev, const char *name)
{
	uint8_t new;

	pci_write_byte(dev, 0x52, 0xee);

	new = pci_read_byte(dev, 0x52);

	if (new != 0xee) {
		printf("tried to set register 0x%x to 0x%x on %s failed (WARNING ONLY)\n", 0x52, new, name);
		return -1;
	}

	return 0;
}

static int enable_flash_sis5595(struct pci_dev *dev, const char *name)
{
	uint8_t new, newer;

	new = pci_read_byte(dev, 0x45);

	new &= (~0x20);		/* Clear bit 5. */
	new |= 0x4;		/* Set bit 2. */

	pci_write_byte(dev, 0x45, new);

	newer = pci_read_byte(dev, 0x45);
	if (newer != new) {
		printf("tried to set register 0x%x to 0x%x on %s failed (WARNING ONLY)\n", 0x45, new, name);
		printf("Stuck at 0x%x\n", newer);
		return -1;
	}

	/* Extended BIOS enable = 1, Lower BIOS Enable = 1 */
	new = pci_read_byte(dev, 0x40);
	new &= 0xFB;
	new |= 0x3;
	pci_write_byte(dev, 0x40, new);
	newer = pci_read_byte(dev, 0x40);
	if (newer != new) {
		printf("tried to set register 0x%x to 0x%x on %s failed (WARNING ONLY)\n", 0x40, new, name);
		printf("Stuck at 0x%x\n", newer);
		return -1;
	}
	return 0;
}

/* Works for AMD-8111, VIA VT82C586A/B, VIA VT82C686A/B. */
static int enable_flash_amd8111(struct pci_dev *dev, const char *name)
{
	uint8_t old, new;

	/* Enable decoding at 0xffb00000 to 0xffffffff. */
	old = pci_read_byte(dev, 0x43);
	new = old | 0xC0;
	if (new != old) {
		pci_write_byte(dev, 0x43, new);
		if (pci_read_byte(dev, 0x43) != new) {
			printf("tried to set 0x%x to 0x%x on %s failed (WARNING ONLY)\n", 0x43, new, name);
		}
	}

	/* Enable 'ROM write' bit. */
	old = pci_read_byte(dev, 0x40);
	new = old | 0x01;
	if (new == old)
		return 0;
	pci_write_byte(dev, 0x40, new);

	if (pci_read_byte(dev, 0x40) != new) {
		printf("tried to set 0x%x to 0x%x on %s failed (WARNING ONLY)\n", 0x40, new, name);
		return -1;
	}

	return 0;
}

static int enable_flash_sb600(struct pci_dev *dev, const char *name)
{
	uint32_t tmp, low_bits, num;
	uint8_t reg;

	low_bits = tmp = pci_read_long(dev, 0xa0);
	low_bits &= ~0xffffc000; /* for mmap aligning requirements */
	low_bits &= 0xfffffff0;	/* remove low 4 bits */
	tmp &= 0xffffc000;
	printf_debug("SPI base address is at 0x%x\n", tmp + low_bits);

	sb600_spibar = mmap(0, 0x4000, PROT_READ | PROT_WRITE, MAP_SHARED,
			    fd_mem, (off_t)tmp);
	if (sb600_spibar == MAP_FAILED) {
		perror("Can't mmap memory using " MEM_DEV);
		exit(1);
	}
	sb600_spibar += low_bits;

	/* Clear ROM protect 0-3. */
	for (reg = 0x50; reg < 0x60; reg += 4) {
		num = pci_read_long(dev, reg);
		num &= 0xfffffffc;
		pci_write_byte(dev, reg, num);
	}

	flashbus = BUS_TYPE_SB600_SPI;

	/* Enable SPI ROM in SB600 PM register. */
	OUTB(0x8f, 0xcd6);
	OUTB(0x0e, 0xcd7);

	return 0;
}

static int enable_flash_ck804(struct pci_dev *dev, const char *name)
{
	uint8_t old, new;

	old = pci_read_byte(dev, 0x88);
	new = old | 0xc0;
	if (new != old) {
		pci_write_byte(dev, 0x88, new);
		if (pci_read_byte(dev, 0x88) != new) {
			printf("tried to set 0x%x to 0x%x on %s failed (WARNING ONLY)\n", 0x88, new, name);
		}
	}

	old = pci_read_byte(dev, 0x6d);
	new = old | 0x01;
	if (new == old)
		return 0;
	pci_write_byte(dev, 0x6d, new);

	if (pci_read_byte(dev, 0x6d) != new) {
		printf("tried to set 0x%x to 0x%x on %s failed (WARNING ONLY)\n", 0x6d, new, name);
		return -1;
	}

	return 0;
}

/* ATI Technologies Inc IXP SB400 PCI-ISA Bridge (rev 80) */
static int enable_flash_sb400(struct pci_dev *dev, const char *name)
{
	uint8_t tmp;
	struct pci_filter f;
	struct pci_dev *smbusdev;

	/* Look for the SMBus device. */
	pci_filter_init((struct pci_access *)0, &f);
	f.vendor = 0x1002;
	f.device = 0x4372;

	for (smbusdev = pacc->devices; smbusdev; smbusdev = smbusdev->next) {
		if (pci_filter_match(&f, smbusdev))
			break;
	}

	if (!smbusdev) {
		fprintf(stderr, "ERROR: SMBus device not found. Aborting.\n");
		exit(1);
	}

	/* Enable some SMBus stuff. */
	tmp = pci_read_byte(smbusdev, 0x79);
	tmp |= 0x01;
	pci_write_byte(smbusdev, 0x79, tmp);

	/* Change southbridge. */
	tmp = pci_read_byte(dev, 0x48);
	tmp |= 0x21;
	pci_write_byte(dev, 0x48, tmp);

	/* Now become a bit silly. */
	tmp = INB(0xc6f);
	OUTB(tmp, 0xeb);
	OUTB(tmp, 0xeb);
	tmp |= 0x40;
	OUTB(tmp, 0xc6f);
	OUTB(tmp, 0xeb);
	OUTB(tmp, 0xeb);

	return 0;
}

static int enable_flash_mcp55(struct pci_dev *dev, const char *name)
{
	uint8_t old, new, byte;
	uint16_t word;

	/* Set the 0-16 MB enable bits. */
	byte = pci_read_byte(dev, 0x88);
	byte |= 0xff;		/* 256K */
	pci_write_byte(dev, 0x88, byte);
	byte = pci_read_byte(dev, 0x8c);
	byte |= 0xff;		/* 1M */
	pci_write_byte(dev, 0x8c, byte);
	word = pci_read_word(dev, 0x90);
	word |= 0x7fff;		/* 16M */
	pci_write_word(dev, 0x90, word);

	old = pci_read_byte(dev, 0x6d);
	new = old | 0x01;
	if (new == old)
		return 0;
	pci_write_byte(dev, 0x6d, new);

	if (pci_read_byte(dev, 0x6d) != new) {
		printf("tried to set 0x%x to 0x%x on %s failed (WARNING ONLY)\n", 0x6d, new, name);
		return -1;
	}

	return 0;
}

static int enable_flash_ht1000(struct pci_dev *dev, const char *name)
{
	uint8_t byte;

	/* Set the 4MB enable bit. */
	byte = pci_read_byte(dev, 0x41);
	byte |= 0x0e;
	pci_write_byte(dev, 0x41, byte);

	byte = pci_read_byte(dev, 0x43);
	byte |= (1 << 4);
	pci_write_byte(dev, 0x43, byte);

	return 0;
}

/**
 * Usually on the x86 architectures (and on other PC-like platforms like some
 * Alphas or Itanium) the system flash is mapped right below 4G. On the AMD
 * Elan SC520 only a small piece of the system flash is mapped there, but the
 * complete flash is mapped somewhere below 1G. The position can be determined
 * by the BOOTCS PAR register.
 */
static int get_flashbase_sc520(struct pci_dev *dev, const char *name)
{
	int i, bootcs_found = 0;
	uint32_t parx = 0;
	void *mmcr;

	/* 1. Map MMCR */
	mmcr = mmap(0, getpagesize(), PROT_WRITE | PROT_READ,
			MAP_SHARED, fd_mem, (off_t)0xFFFEF000);

	if (mmcr == MAP_FAILED) {
		perror("Can't mmap Elan SC520 specific registers using " MEM_DEV);
		exit(1);
	}

	/* 2. Scan PAR0 (0x88) - PAR15 (0xc4) for
	 *    BOOTCS region (PARx[31:29] = 100b)e
	 */
	for (i = 0x88; i <= 0xc4; i += 4) {
		parx = *(volatile uint32_t *)(mmcr + i);
		if ((parx >> 29) == 4) {
			bootcs_found = 1;
			break; /* BOOTCS found */
		}
	}

	/* 3. PARx[25] = 1b --> flashbase[29:16] = PARx[13:0]
	 *    PARx[25] = 0b --> flashbase[29:12] = PARx[17:0]
	 */
	if (bootcs_found) {
		if (parx & (1 << 25)) {
			parx &= (1 << 14) - 1; /* Mask [13:0] */
			flashbase = parx << 16;
		} else {
			parx &= (1 << 18) - 1; /* Mask [17:0] */
			flashbase = parx << 12;
		}
	} else {
		printf("AMD Elan SC520 detected, but no BOOTCS. Assuming flash at 4G\n");
	}

	/* 4. Clean up */
	munmap (mmcr, getpagesize());
	return 0;
}

typedef struct penable {
	uint16_t vendor, device;
	const char *name;
	int (*doit) (struct pci_dev *dev, const char *name);
} FLASH_ENABLE;

static const FLASH_ENABLE enables[] = {
	{0x1039, 0x0630, "SiS630",		enable_flash_sis630},
	{0x8086, 0x122e, "Intel PIIX",		enable_flash_piix4},
	{0x8086, 0x1234, "Intel MPIIX",		enable_flash_piix4},
	{0x8086, 0x7000, "Intel PIIX3",		enable_flash_piix4},
	{0x8086, 0x7110, "Intel PIIX4/4E/4M",	enable_flash_piix4},
	{0x8086, 0x7198, "Intel 440MX",		enable_flash_piix4},
	{0x8086, 0x2410, "Intel ICH",		enable_flash_ich_4e},
	{0x8086, 0x2420, "Intel ICH0",		enable_flash_ich_4e},
	{0x8086, 0x2440, "Intel ICH2",		enable_flash_ich_4e},
	{0x8086, 0x244c, "Intel ICH2-M",	enable_flash_ich_4e},
	{0x8086, 0x2480, "Intel ICH3-S",	enable_flash_ich_4e},
	{0x8086, 0x248c, "Intel ICH3-M",	enable_flash_ich_4e},
	{0x8086, 0x24c0, "Intel ICH4/ICH4-L",	enable_flash_ich_4e},
	{0x8086, 0x24cc, "Intel ICH4-M",	enable_flash_ich_4e},
	{0x8086, 0x24d0, "Intel ICH5/ICH5R",	enable_flash_ich_4e},
	{0x8086, 0x25a1, "Intel 6300ESB",	enable_flash_ich_4e},
	{0x8086, 0x2640, "Intel ICH6/ICH6R",	enable_flash_ich_dc},
	{0x8086, 0x2641, "Intel ICH6-M",	enable_flash_ich_dc},
	{0x8086, 0x5031, "Intel EP80579",	enable_flash_ich7},
	{0x8086, 0x27b0, "Intel ICH7DH",	enable_flash_ich7},
	{0x8086, 0x27b8, "Intel ICH7/ICH7R",	enable_flash_ich7},
	{0x8086, 0x27b9, "Intel ICH7M",		enable_flash_ich7},
	{0x8086, 0x27bd, "Intel ICH7MDH",	enable_flash_ich7},
	{0x8086, 0x2810, "Intel ICH8/ICH8R",	enable_flash_ich8},
	{0x8086, 0x2811, "Intel ICH8M-E",	enable_flash_ich8},
	{0x8086, 0x2812, "Intel ICH8DH",	enable_flash_ich8},
	{0x8086, 0x2814, "Intel ICH8DO",	enable_flash_ich8},
	{0x8086, 0x2815, "Intel ICH8M",		enable_flash_ich8},
	{0x8086, 0x2912, "Intel ICH9DH",	enable_flash_ich9},
	{0x8086, 0x2914, "Intel ICH9DO",	enable_flash_ich9},
	{0x8086, 0x2916, "Intel ICH9R",		enable_flash_ich9},
	{0x8086, 0x2917, "Intel ICH9M-E",	enable_flash_ich9},
	{0x8086, 0x2918, "Intel ICH9",		enable_flash_ich9},
	{0x8086, 0x2919, "Intel ICH9M",		enable_flash_ich9},
	{0x8086, 0x3a14, "Intel ICH10DO",	enable_flash_ich10},
	{0x8086, 0x3a16, "Intel ICH10R",	enable_flash_ich10},
	{0x8086, 0x3a18, "Intel ICH10",		enable_flash_ich10},
	{0x8086, 0x3a1a, "Intel ICH10D",	enable_flash_ich10},
	{0x1106, 0x8231, "VIA VT8231",		enable_flash_vt823x},
	{0x1106, 0x3177, "VIA VT8235",		enable_flash_vt823x},
	{0x1106, 0x3227, "VIA VT8237",		enable_flash_vt823x},
	{0x1106, 0x3372, "VIA VT8237S",		enable_flash_vt8237s_spi},
	{0x1106, 0x8324, "VIA CX700",		enable_flash_vt823x},
	{0x1106, 0x0586, "VIA VT82C586A/B",	enable_flash_amd8111},
	{0x1106, 0x0686, "VIA VT82C686A/B",	enable_flash_amd8111},
	{0x1078, 0x0100, "AMD CS5530(A)",	enable_flash_cs5530},
	{0x100b, 0x0510, "AMD SC1100",		enable_flash_sc1100},
	{0x1039, 0x0008, "SiS5595",		enable_flash_sis5595},
	{0x1022, 0x2080, "AMD CS5536",		enable_flash_cs5536},
	{0x1022, 0x7468, "AMD8111",		enable_flash_amd8111},
	{0x1002, 0x438D, "ATI(AMD) SB600",	enable_flash_sb600},
	{0x1002, 0x439d, "ATI(AMD) SB700",	enable_flash_sb600},
	{0x10B9, 0x1533, "ALi M1533",		enable_flash_ali_m1533},
	{0x10de, 0x0050, "NVIDIA CK804",	enable_flash_ck804}, /* LPC */
	{0x10de, 0x0051, "NVIDIA CK804",	enable_flash_ck804}, /* Pro */
	/* Slave, should not be here, to fix known bug for A01. */
	{0x10de, 0x00d3, "NVIDIA CK804",	enable_flash_ck804},
	{0x10de, 0x0260, "NVIDIA MCP51",	enable_flash_ck804},
	{0x10de, 0x0261, "NVIDIA MCP51",	enable_flash_ck804},
	{0x10de, 0x0262, "NVIDIA MCP51",	enable_flash_ck804},
	{0x10de, 0x0263, "NVIDIA MCP51",	enable_flash_ck804},
	{0x10de, 0x0360, "NVIDIA MCP55",	enable_flash_mcp55}, /* M57SLI*/
	{0x10de, 0x0361, "NVIDIA MCP55",	enable_flash_mcp55}, /* LPC */
	{0x10de, 0x0362, "NVIDIA MCP55",	enable_flash_mcp55}, /* LPC */
	{0x10de, 0x0363, "NVIDIA MCP55",	enable_flash_mcp55}, /* LPC */
	{0x10de, 0x0364, "NVIDIA MCP55",	enable_flash_mcp55}, /* LPC */
	{0x10de, 0x0365, "NVIDIA MCP55",	enable_flash_mcp55}, /* LPC */
	{0x10de, 0x0366, "NVIDIA MCP55",	enable_flash_mcp55}, /* LPC */
	{0x10de, 0x0367, "NVIDIA MCP55",	enable_flash_mcp55}, /* Pro */
	{0x10de, 0x0548, "NVIDIA MCP67",	enable_flash_mcp55},
	{0x1002, 0x4377, "ATI SB400",		enable_flash_sb400},
	{0x1166, 0x0205, "Broadcom HT-1000",	enable_flash_ht1000},
	{0x1022, 0x3000, "AMD Elan SC520",	get_flashbase_sc520},
};

void print_supported_chipsets(void)
{
	int i;

	printf("\nSupported chipsets:\n\n");

	for (i = 0; i < ARRAY_SIZE(enables); i++)
		printf("%s (%04x:%04x)\n", enables[i].name,
		       enables[i].vendor, enables[i].device);
}

int chipset_flash_enable(void)
{
	struct pci_dev *dev = 0;
	int ret = -2;		/* Nothing! */
	int i;

	/* Now let's try to find the chipset we have... */
	for (i = 0; i < ARRAY_SIZE(enables); i++) {
		dev = pci_dev_find(enables[i].vendor, enables[i].device);
		if (dev)
			break;
	}

	if (dev) {
		printf("Found chipset \"%s\", enabling flash write... ",
		       enables[i].name);

		ret = enables[i].doit(dev, enables[i].name);
		if (ret)
			printf("FAILED!\n");
		else
			printf("OK.\n");
	}

	return ret;
}