summaryrefslogtreecommitdiffstats
path: root/arch/x86_64/kernel/mpparse.c
blob: 1105250bf02c3ee26d8b1f8a54ab78904e85ca5a (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
/*
 *	Intel Multiprocessor Specification 1.1 and 1.4
 *	compliant MP-table parsing routines.
 *
 *	(c) 1995 Alan Cox, Building #3 <alan@redhat.com>
 *	(c) 1998, 1999, 2000 Ingo Molnar <mingo@redhat.com>
 *
 *	Fixes
 *		Erich Boleyn	:	MP v1.4 and additional changes.
 *		Alan Cox	:	Added EBDA scanning
 *		Ingo Molnar	:	various cleanups and rewrites
 *		Maciej W. Rozycki:	Bits for default MP configurations
 *		Paul Diefenbaugh:	Added full ACPI support
 */

#include <linux/mm.h>
#include <linux/init.h>
#include <linux/delay.h>
#include <linux/config.h>
#include <linux/bootmem.h>
#include <linux/smp_lock.h>
#include <linux/kernel_stat.h>
#include <linux/mc146818rtc.h>
#include <linux/acpi.h>
#include <linux/module.h>

#include <asm/smp.h>
#include <asm/mtrr.h>
#include <asm/mpspec.h>
#include <asm/pgalloc.h>
#include <asm/io_apic.h>
#include <asm/proto.h>
#include <asm/acpi.h>

/* Have we found an MP table */
int smp_found_config;
unsigned int __initdata maxcpus = NR_CPUS;

int acpi_found_madt;

/*
 * Various Linux-internal data structures created from the
 * MP-table.
 */
unsigned char apic_version [MAX_APICS];
unsigned char mp_bus_id_to_type [MAX_MP_BUSSES] = { [0 ... MAX_MP_BUSSES-1] = -1 };
int mp_bus_id_to_pci_bus [MAX_MP_BUSSES] = { [0 ... MAX_MP_BUSSES-1] = -1 };

static int mp_current_pci_id = 0;
/* I/O APIC entries */
struct mpc_config_ioapic mp_ioapics[MAX_IO_APICS];

/* # of MP IRQ source entries */
struct mpc_config_intsrc mp_irqs[MAX_IRQ_SOURCES];

/* MP IRQ source entries */
int mp_irq_entries;

int nr_ioapics;
int pic_mode;
unsigned long mp_lapic_addr = 0;



/* Processor that is doing the boot up */
unsigned int boot_cpu_id = -1U;
/* Internal processor count */
unsigned int num_processors __initdata = 0;

unsigned disabled_cpus __initdata;

/* Bitmask of physically existing CPUs */
physid_mask_t phys_cpu_present_map = PHYSID_MASK_NONE;

/* ACPI MADT entry parsing functions */
#ifdef CONFIG_ACPI
extern struct acpi_boot_flags acpi_boot;
#ifdef CONFIG_X86_LOCAL_APIC
extern int acpi_parse_lapic (acpi_table_entry_header *header);
extern int acpi_parse_lapic_addr_ovr (acpi_table_entry_header *header);
extern int acpi_parse_lapic_nmi (acpi_table_entry_header *header);
#endif /*CONFIG_X86_LOCAL_APIC*/
#ifdef CONFIG_X86_IO_APIC
extern int acpi_parse_ioapic (acpi_table_entry_header *header);
#endif /*CONFIG_X86_IO_APIC*/
#endif /*CONFIG_ACPI*/

u8 bios_cpu_apicid[NR_CPUS] = { [0 ... NR_CPUS-1] = BAD_APICID };


/*
 * Intel MP BIOS table parsing routines:
 */

/*
 * Checksum an MP configuration block.
 */

static int __init mpf_checksum(unsigned char *mp, int len)
{
	int sum = 0;

	while (len--)
		sum += *mp++;

	return sum & 0xFF;
}

static void __init MP_processor_info (struct mpc_config_processor *m)
{
	int cpu;
	unsigned char ver;
	static int found_bsp=0;

	if (!(m->mpc_cpuflag & CPU_ENABLED)) {
		disabled_cpus++;
		return;
	}

	printk(KERN_INFO "Processor #%d %d:%d APIC version %d\n",
		m->mpc_apicid,
	       (m->mpc_cpufeature & CPU_FAMILY_MASK)>>8,
	       (m->mpc_cpufeature & CPU_MODEL_MASK)>>4,
		m->mpc_apicver);

	if (m->mpc_cpuflag & CPU_BOOTPROCESSOR) {
		Dprintk("    Bootup CPU\n");
		boot_cpu_id = m->mpc_apicid;
	}
	if (num_processors >= NR_CPUS) {
		printk(KERN_WARNING "WARNING: NR_CPUS limit of %i reached."
			" Processor ignored.\n", NR_CPUS);
		return;
	}

	cpu = num_processors++;
	
#if MAX_APICS < 255	
	if ((int)m->mpc_apicid > MAX_APICS) {
		printk(KERN_ERR "Processor #%d INVALID. (Max ID: %d).\n",
			m->mpc_apicid, MAX_APICS);
		return;
	}
#endif
	ver = m->mpc_apicver;

	physid_set(m->mpc_apicid, phys_cpu_present_map);
	/*
	 * Validate version
	 */
	if (ver == 0x0) {
		printk(KERN_ERR "BIOS bug, APIC version is 0 for CPU#%d! fixing up to 0x10. (tell your hw vendor)\n", m->mpc_apicid);
		ver = 0x10;
	}
	apic_version[m->mpc_apicid] = ver;
 	if (m->mpc_cpuflag & CPU_BOOTPROCESSOR) {
 		/*
 		 * bios_cpu_apicid is required to have processors listed
 		 * in same order as logical cpu numbers. Hence the first
 		 * entry is BSP, and so on.
 		 */
		cpu = 0;

 		bios_cpu_apicid[0] = m->mpc_apicid;
 		x86_cpu_to_apicid[0] = m->mpc_apicid;
 		found_bsp = 1;
 	} else
		cpu = num_processors - found_bsp;
	bios_cpu_apicid[cpu] = m->mpc_apicid;
	x86_cpu_to_apicid[cpu] = m->mpc_apicid;

	cpu_set(cpu, cpu_possible_map);
	cpu_set(cpu, cpu_present_map);
}

static void __init MP_bus_info (struct mpc_config_bus *m)
{
	char str[7];

	memcpy(str, m->mpc_bustype, 6);
	str[6] = 0;
	Dprintk("Bus #%d is %s\n", m->mpc_busid, str);

	if (strncmp(str, "ISA", 3) == 0) {
		mp_bus_id_to_type[m->mpc_busid] = MP_BUS_ISA;
	} else if (strncmp(str, "EISA", 4) == 0) {
		mp_bus_id_to_type[m->mpc_busid] = MP_BUS_EISA;
	} else if (strncmp(str, "PCI", 3) == 0) {
		mp_bus_id_to_type[m->mpc_busid] = MP_BUS_PCI;
		mp_bus_id_to_pci_bus[m->mpc_busid] = mp_current_pci_id;
		mp_current_pci_id++;
	} else if (strncmp(str, "MCA", 3) == 0) {
		mp_bus_id_to_type[m->mpc_busid] = MP_BUS_MCA;
	} else {
		printk(KERN_ERR "Unknown bustype %s\n", str);
	}
}

static void __init MP_ioapic_info (struct mpc_config_ioapic *m)
{
	if (!(m->mpc_flags & MPC_APIC_USABLE))
		return;

	printk("I/O APIC #%d Version %d at 0x%X.\n",
		m->mpc_apicid, m->mpc_apicver, m->mpc_apicaddr);
	if (nr_ioapics >= MAX_IO_APICS) {
		printk(KERN_ERR "Max # of I/O APICs (%d) exceeded (found %d).\n",
			MAX_IO_APICS, nr_ioapics);
		panic("Recompile kernel with bigger MAX_IO_APICS!.\n");
	}
	if (!m->mpc_apicaddr) {
		printk(KERN_ERR "WARNING: bogus zero I/O APIC address"
			" found in MP table, skipping!\n");
		return;
	}
	mp_ioapics[nr_ioapics] = *m;
	nr_ioapics++;
}

static void __init MP_intsrc_info (struct mpc_config_intsrc *m)
{
	mp_irqs [mp_irq_entries] = *m;
	Dprintk("Int: type %d, pol %d, trig %d, bus %d,"
		" IRQ %02x, APIC ID %x, APIC INT %02x\n",
			m->mpc_irqtype, m->mpc_irqflag & 3,
			(m->mpc_irqflag >> 2) & 3, m->mpc_srcbus,
			m->mpc_srcbusirq, m->mpc_dstapic, m->mpc_dstirq);
	if (++mp_irq_entries >= MAX_IRQ_SOURCES)
		panic("Max # of irq sources exceeded!!\n");
}

static void __init MP_lintsrc_info (struct mpc_config_lintsrc *m)
{
	Dprintk("Lint: type %d, pol %d, trig %d, bus %d,"
		" IRQ %02x, APIC ID %x, APIC LINT %02x\n",
			m->mpc_irqtype, m->mpc_irqflag & 3,
			(m->mpc_irqflag >> 2) &3, m->mpc_srcbusid,
			m->mpc_srcbusirq, m->mpc_destapic, m->mpc_destapiclint);
	/*
	 * Well it seems all SMP boards in existence
	 * use ExtINT/LVT1 == LINT0 and
	 * NMI/LVT2 == LINT1 - the following check
	 * will show us if this assumptions is false.
	 * Until then we do not have to add baggage.
	 */
	if ((m->mpc_irqtype == mp_ExtINT) &&
		(m->mpc_destapiclint != 0))
			BUG();
	if ((m->mpc_irqtype == mp_NMI) &&
		(m->mpc_destapiclint != 1))
			BUG();
}

/*
 * Read/parse the MPC
 */

static int __init smp_read_mpc(struct mp_config_table *mpc)
{
	char str[16];
	int count=sizeof(*mpc);
	unsigned char *mpt=((unsigned char *)mpc)+count;

	if (memcmp(mpc->mpc_signature,MPC_SIGNATURE,4)) {
		printk("SMP mptable: bad signature [%c%c%c%c]!\n",
			mpc->mpc_signature[0],
			mpc->mpc_signature[1],
			mpc->mpc_signature[2],
			mpc->mpc_signature[3]);
		return 0;
	}
	if (mpf_checksum((unsigned char *)mpc,mpc->mpc_length)) {
		printk("SMP mptable: checksum error!\n");
		return 0;
	}
	if (mpc->mpc_spec!=0x01 && mpc->mpc_spec!=0x04) {
		printk(KERN_ERR "SMP mptable: bad table version (%d)!!\n",
			mpc->mpc_spec);
		return 0;
	}
	if (!mpc->mpc_lapic) {
		printk(KERN_ERR "SMP mptable: null local APIC address!\n");
		return 0;
	}
	memcpy(str,mpc->mpc_oem,8);
	str[8]=0;
	printk(KERN_INFO "OEM ID: %s ",str);

	memcpy(str,mpc->mpc_productid,12);
	str[12]=0;
	printk(KERN_INFO "Product ID: %s ",str);

	printk(KERN_INFO "APIC at: 0x%X\n",mpc->mpc_lapic);

	/* save the local APIC address, it might be non-default */
	if (!acpi_lapic)
	mp_lapic_addr = mpc->mpc_lapic;

	/*
	 *	Now process the configuration blocks.
	 */
	while (count < mpc->mpc_length) {
		switch(*mpt) {
			case MP_PROCESSOR:
			{
				struct mpc_config_processor *m=
					(struct mpc_config_processor *)mpt;
				if (!acpi_lapic)
				MP_processor_info(m);
				mpt += sizeof(*m);
				count += sizeof(*m);
				break;
			}
			case MP_BUS:
			{
				struct mpc_config_bus *m=
					(struct mpc_config_bus *)mpt;
				MP_bus_info(m);
				mpt += sizeof(*m);
				count += sizeof(*m);
				break;
			}
			case MP_IOAPIC:
			{
				struct mpc_config_ioapic *m=
					(struct mpc_config_ioapic *)mpt;
				MP_ioapic_info(m);
				mpt+=sizeof(*m);
				count+=sizeof(*m);
				break;
			}
			case MP_INTSRC:
			{
				struct mpc_config_intsrc *m=
					(struct mpc_config_intsrc *)mpt;

				MP_intsrc_info(m);
				mpt+=sizeof(*m);
				count+=sizeof(*m);
				break;
			}
			case MP_LINTSRC:
			{
				struct mpc_config_lintsrc *m=
					(struct mpc_config_lintsrc *)mpt;
				MP_lintsrc_info(m);
				mpt+=sizeof(*m);
				count+=sizeof(*m);
				break;
			}
		}
	}
	clustered_apic_check();
	if (!num_processors)
		printk(KERN_ERR "SMP mptable: no processors registered!\n");
	return num_processors;
}

static int __init ELCR_trigger(unsigned int irq)
{
	unsigned int port;

	port = 0x4d0 + (irq >> 3);
	return (inb(port) >> (irq & 7)) & 1;
}

static void __init construct_default_ioirq_mptable(int mpc_default_type)
{
	struct mpc_config_intsrc intsrc;
	int i;
	int ELCR_fallback = 0;

	intsrc.mpc_type = MP_INTSRC;
	intsrc.mpc_irqflag = 0;			/* conforming */
	intsrc.mpc_srcbus = 0;
	intsrc.mpc_dstapic = mp_ioapics[0].mpc_apicid;

	intsrc.mpc_irqtype = mp_INT;

	/*
	 *  If true, we have an ISA/PCI system with no IRQ entries
	 *  in the MP table. To prevent the PCI interrupts from being set up
	 *  incorrectly, we try to use the ELCR. The sanity check to see if
	 *  there is good ELCR data is very simple - IRQ0, 1, 2 and 13 can
	 *  never be level sensitive, so we simply see if the ELCR agrees.
	 *  If it does, we assume it's valid.
	 */
	if (mpc_default_type == 5) {
		printk(KERN_INFO "ISA/PCI bus type with no IRQ information... falling back to ELCR\n");

		if (ELCR_trigger(0) || ELCR_trigger(1) || ELCR_trigger(2) || ELCR_trigger(13))
			printk(KERN_ERR "ELCR contains invalid data... not using ELCR\n");
		else {
			printk(KERN_INFO "Using ELCR to identify PCI interrupts\n");
			ELCR_fallback = 1;
		}
	}

	for (i = 0; i < 16; i++) {
		switch (mpc_default_type) {
		case 2:
			if (i == 0 || i == 13)
				continue;	/* IRQ0 & IRQ13 not connected */
			/* fall through */
		default:
			if (i == 2)
				continue;	/* IRQ2 is never connected */
		}

		if (ELCR_fallback) {
			/*
			 *  If the ELCR indicates a level-sensitive interrupt, we
			 *  copy that information over to the MP table in the
			 *  irqflag field (level sensitive, active high polarity).
			 */
			if (ELCR_trigger(i))
				intsrc.mpc_irqflag = 13;
			else
				intsrc.mpc_irqflag = 0;
		}

		intsrc.mpc_srcbusirq = i;
		intsrc.mpc_dstirq = i ? i : 2;		/* IRQ0 to INTIN2 */
		MP_intsrc_info(&intsrc);
	}

	intsrc.mpc_irqtype = mp_ExtINT;
	intsrc.mpc_srcbusirq = 0;
	intsrc.mpc_dstirq = 0;				/* 8259A to INTIN0 */
	MP_intsrc_info(&intsrc);
}

static inline void __init construct_default_ISA_mptable(int mpc_default_type)
{
	struct mpc_config_processor processor;
	struct mpc_config_bus bus;
	struct mpc_config_ioapic ioapic;
	struct mpc_config_lintsrc lintsrc;
	int linttypes[2] = { mp_ExtINT, mp_NMI };
	int i;

	/*
	 * local APIC has default address
	 */
	mp_lapic_addr = APIC_DEFAULT_PHYS_BASE;

	/*
	 * 2 CPUs, numbered 0 & 1.
	 */
	processor.mpc_type = MP_PROCESSOR;
	/* Either an integrated APIC or a discrete 82489DX. */
	processor.mpc_apicver = mpc_default_type > 4 ? 0x10 : 0x01;
	processor.mpc_cpuflag = CPU_ENABLED;
	processor.mpc_cpufeature = (boot_cpu_data.x86 << 8) |
				   (boot_cpu_data.x86_model << 4) |
				   boot_cpu_data.x86_mask;
	processor.mpc_featureflag = boot_cpu_data.x86_capability[0];
	processor.mpc_reserved[0] = 0;
	processor.mpc_reserved[1] = 0;
	for (i = 0; i < 2; i++) {
		processor.mpc_apicid = i;
		MP_processor_info(&processor);
	}

	bus.mpc_type = MP_BUS;
	bus.mpc_busid = 0;
	switch (mpc_default_type) {
		default:
			printk(KERN_ERR "???\nUnknown standard configuration %d\n",
				mpc_default_type);
			/* fall through */
		case 1:
		case 5:
			memcpy(bus.mpc_bustype, "ISA   ", 6);
			break;
		case 2:
		case 6:
		case 3:
			memcpy(bus.mpc_bustype, "EISA  ", 6);
			break;
		case 4:
		case 7:
			memcpy(bus.mpc_bustype, "MCA   ", 6);
	}
	MP_bus_info(&bus);
	if (mpc_default_type > 4) {
		bus.mpc_busid = 1;
		memcpy(bus.mpc_bustype, "PCI   ", 6);
		MP_bus_info(&bus);
	}

	ioapic.mpc_type = MP_IOAPIC;
	ioapic.mpc_apicid = 2;
	ioapic.mpc_apicver = mpc_default_type > 4 ? 0x10 : 0x01;
	ioapic.mpc_flags = MPC_APIC_USABLE;
	ioapic.mpc_apicaddr = 0xFEC00000;
	MP_ioapic_info(&ioapic);

	/*
	 * We set up most of the low 16 IO-APIC pins according to MPS rules.
	 */
	construct_default_ioirq_mptable(mpc_default_type);

	lintsrc.mpc_type = MP_LINTSRC;
	lintsrc.mpc_irqflag = 0;		/* conforming */
	lintsrc.mpc_srcbusid = 0;
	lintsrc.mpc_srcbusirq = 0;
	lintsrc.mpc_destapic = MP_APIC_ALL;
	for (i = 0; i < 2; i++) {
		lintsrc.mpc_irqtype = linttypes[i];
		lintsrc.mpc_destapiclint = i;
		MP_lintsrc_info(&lintsrc);
	}
}

static struct intel_mp_floating *mpf_found;

/*
 * Scan the memory blocks for an SMP configuration block.
 */
void __init get_smp_config (void)
{
	struct intel_mp_floating *mpf = mpf_found;

	/*
 	 * ACPI supports both logical (e.g. Hyper-Threading) and physical 
 	 * processors, where MPS only supports physical.
 	 */
 	if (acpi_lapic && acpi_ioapic) {
 		printk(KERN_INFO "Using ACPI (MADT) for SMP configuration information\n");
 		return;
	}
 	else if (acpi_lapic)
 		printk(KERN_INFO "Using ACPI for processor (LAPIC) configuration information\n");

	printk("Intel MultiProcessor Specification v1.%d\n", mpf->mpf_specification);
	if (mpf->mpf_feature2 & (1<<7)) {
		printk(KERN_INFO "    IMCR and PIC compatibility mode.\n");
		pic_mode = 1;
	} else {
		printk(KERN_INFO "    Virtual Wire compatibility mode.\n");
		pic_mode = 0;
	}

	/*
	 * Now see if we need to read further.
	 */
	if (mpf->mpf_feature1 != 0) {

		printk(KERN_INFO "Default MP configuration #%d\n", mpf->mpf_feature1);
		construct_default_ISA_mptable(mpf->mpf_feature1);

	} else if (mpf->mpf_physptr) {

		/*
		 * Read the physical hardware table.  Anything here will
		 * override the defaults.
		 */
		if (!smp_read_mpc(phys_to_virt(mpf->mpf_physptr))) {
			smp_found_config = 0;
			printk(KERN_ERR "BIOS bug, MP table errors detected!...\n");
			printk(KERN_ERR "... disabling SMP support. (tell your hw vendor)\n");
			return;
		}
		/*
		 * If there are no explicit MP IRQ entries, then we are
		 * broken.  We set up most of the low 16 IO-APIC pins to
		 * ISA defaults and hope it will work.
		 */
		if (!mp_irq_entries) {
			struct mpc_config_bus bus;

			printk(KERN_ERR "BIOS bug, no explicit IRQ entries, using default mptable. (tell your hw vendor)\n");

			bus.mpc_type = MP_BUS;
			bus.mpc_busid = 0;
			memcpy(bus.mpc_bustype, "ISA   ", 6);
			MP_bus_info(&bus);

			construct_default_ioirq_mptable(0);
		}

	} else
		BUG();

	printk(KERN_INFO "Processors: %d\n", num_processors);
	/*
	 * Only use the first configuration found.
	 */
}

static int __init smp_scan_config (unsigned long base, unsigned long length)
{
	extern void __bad_mpf_size(void); 
	unsigned int *bp = phys_to_virt(base);
	struct intel_mp_floating *mpf;

	Dprintk("Scan SMP from %p for %ld bytes.\n", bp,length);
	if (sizeof(*mpf) != 16)
		__bad_mpf_size();

	while (length > 0) {
		mpf = (struct intel_mp_floating *)bp;
		if ((*bp == SMP_MAGIC_IDENT) &&
			(mpf->mpf_length == 1) &&
			!mpf_checksum((unsigned char *)bp, 16) &&
			((mpf->mpf_specification == 1)
				|| (mpf->mpf_specification == 4)) ) {

			smp_found_config = 1;
			reserve_bootmem_generic(virt_to_phys(mpf), PAGE_SIZE);
			if (mpf->mpf_physptr)
				reserve_bootmem_generic(mpf->mpf_physptr, PAGE_SIZE);
			mpf_found = mpf;
			return 1;
		}
		bp += 4;
		length -= 16;
	}
	return 0;
}

void __init find_intel_smp (void)
{
	unsigned int address;

	/*
	 * FIXME: Linux assumes you have 640K of base ram..
	 * this continues the error...
	 *
	 * 1) Scan the bottom 1K for a signature
	 * 2) Scan the top 1K of base RAM
	 * 3) Scan the 64K of bios
	 */
	if (smp_scan_config(0x0,0x400) ||
		smp_scan_config(639*0x400,0x400) ||
			smp_scan_config(0xF0000,0x10000))
		return;
	/*
	 * If it is an SMP machine we should know now, unless the
	 * configuration is in an EISA/MCA bus machine with an
	 * extended bios data area.
	 *
	 * there is a real-mode segmented pointer pointing to the
	 * 4K EBDA area at 0x40E, calculate and scan it here.
	 *
	 * NOTE! There are Linux loaders that will corrupt the EBDA
	 * area, and as such this kind of SMP config may be less
	 * trustworthy, simply because the SMP table may have been
	 * stomped on during early boot. These loaders are buggy and
	 * should be fixed.
	 */

	address = *(unsigned short *)phys_to_virt(0x40E);
	address <<= 4;
	if (smp_scan_config(address, 0x1000))
		return;

	/* If we have come this far, we did not find an MP table  */
	 printk(KERN_INFO "No mptable found.\n");
}

/*
 * - Intel MP Configuration Table
 */
void __init find_smp_config (void)
{
#ifdef CONFIG_X86_LOCAL_APIC
	find_intel_smp();
#endif
}


/* --------------------------------------------------------------------------
                            ACPI-based MP Configuration
   -------------------------------------------------------------------------- */

#ifdef CONFIG_ACPI

void __init mp_register_lapic_address (
	u64			address)
{
	mp_lapic_addr = (unsigned long) address;

	set_fixmap_nocache(FIX_APIC_BASE, mp_lapic_addr);

	if (boot_cpu_id == -1U)
		boot_cpu_id = GET_APIC_ID(apic_read(APIC_ID));

	Dprintk("Boot CPU = %d\n", boot_cpu_physical_apicid);
}


void __init mp_register_lapic (
	u8			id, 
	u8			enabled)
{
	struct mpc_config_processor processor;
	int			boot_cpu = 0;
	
	if (id >= MAX_APICS) {
		printk(KERN_WARNING "Processor #%d invalid (max %d)\n",
			id, MAX_APICS);
		return;
	}

	if (id == boot_cpu_physical_apicid)
		boot_cpu = 1;

	processor.mpc_type = MP_PROCESSOR;
	processor.mpc_apicid = id;
	processor.mpc_apicver = GET_APIC_VERSION(apic_read(APIC_LVR));
	processor.mpc_cpuflag = (enabled ? CPU_ENABLED : 0);
	processor.mpc_cpuflag |= (boot_cpu ? CPU_BOOTPROCESSOR : 0);
	processor.mpc_cpufeature = (boot_cpu_data.x86 << 8) | 
		(boot_cpu_data.x86_model << 4) | boot_cpu_data.x86_mask;
	processor.mpc_featureflag = boot_cpu_data.x86_capability[0];
	processor.mpc_reserved[0] = 0;
	processor.mpc_reserved[1] = 0;

	MP_processor_info(&processor);
}

#ifdef CONFIG_X86_IO_APIC

#define MP_ISA_BUS		0
#define MP_MAX_IOAPIC_PIN	127

static struct mp_ioapic_routing {
	int			apic_id;
	int			gsi_start;
	int			gsi_end;
	u32			pin_programmed[4];
} mp_ioapic_routing[MAX_IO_APICS];


static int mp_find_ioapic (
	int			gsi)
{
	int			i = 0;

	/* Find the IOAPIC that manages this GSI. */
	for (i = 0; i < nr_ioapics; i++) {
		if ((gsi >= mp_ioapic_routing[i].gsi_start)
			&& (gsi <= mp_ioapic_routing[i].gsi_end))
			return i;
	}

	printk(KERN_ERR "ERROR: Unable to locate IOAPIC for GSI %d\n", gsi);

	return -1;
}
	

void __init mp_register_ioapic (
	u8			id, 
	u32			address,
	u32			gsi_base)
{
	int			idx = 0;

	if (nr_ioapics >= MAX_IO_APICS) {
		printk(KERN_ERR "ERROR: Max # of I/O APICs (%d) exceeded "
			"(found %d)\n", MAX_IO_APICS, nr_ioapics);
		panic("Recompile kernel with bigger MAX_IO_APICS!\n");
	}
	if (!address) {
		printk(KERN_ERR "WARNING: Bogus (zero) I/O APIC address"
			" found in MADT table, skipping!\n");
		return;
	}

	idx = nr_ioapics++;

	mp_ioapics[idx].mpc_type = MP_IOAPIC;
	mp_ioapics[idx].mpc_flags = MPC_APIC_USABLE;
	mp_ioapics[idx].mpc_apicaddr = address;

	set_fixmap_nocache(FIX_IO_APIC_BASE_0 + idx, address);
	mp_ioapics[idx].mpc_apicid = id;
	mp_ioapics[idx].mpc_apicver = io_apic_get_version(idx);
	
	/* 
	 * Build basic IRQ lookup table to facilitate gsi->io_apic lookups
	 * and to prevent reprogramming of IOAPIC pins (PCI IRQs).
	 */
	mp_ioapic_routing[idx].apic_id = mp_ioapics[idx].mpc_apicid;
	mp_ioapic_routing[idx].gsi_start = gsi_base;
	mp_ioapic_routing[idx].gsi_end = gsi_base + 
		io_apic_get_redir_entries(idx);

	printk(KERN_INFO "IOAPIC[%d]: apic_id %d, version %d, address 0x%x, "
		"GSI %d-%d\n", idx, mp_ioapics[idx].mpc_apicid, 
		mp_ioapics[idx].mpc_apicver, mp_ioapics[idx].mpc_apicaddr,
		mp_ioapic_routing[idx].gsi_start,
		mp_ioapic_routing[idx].gsi_end);

	return;
}


void __init mp_override_legacy_irq (
	u8			bus_irq,
	u8			polarity, 
	u8			trigger, 
	u32			gsi)
{
	struct mpc_config_intsrc intsrc;
	int			ioapic = -1;
	int			pin = -1;

	/* 
	 * Convert 'gsi' to 'ioapic.pin'.
	 */
	ioapic = mp_find_ioapic(gsi);
	if (ioapic < 0)
		return;
	pin = gsi - mp_ioapic_routing[ioapic].gsi_start;

	/*
	 * TBD: This check is for faulty timer entries, where the override
	 *      erroneously sets the trigger to level, resulting in a HUGE 
	 *      increase of timer interrupts!
	 */
	if ((bus_irq == 0) && (trigger == 3))
		trigger = 1;

	intsrc.mpc_type = MP_INTSRC;
	intsrc.mpc_irqtype = mp_INT;
	intsrc.mpc_irqflag = (trigger << 2) | polarity;
	intsrc.mpc_srcbus = MP_ISA_BUS;
	intsrc.mpc_srcbusirq = bus_irq;				       /* IRQ */
	intsrc.mpc_dstapic = mp_ioapics[ioapic].mpc_apicid;	   /* APIC ID */
	intsrc.mpc_dstirq = pin;				    /* INTIN# */

	Dprintk("Int: type %d, pol %d, trig %d, bus %d, irq %d, %d-%d\n", 
		intsrc.mpc_irqtype, intsrc.mpc_irqflag & 3, 
		(intsrc.mpc_irqflag >> 2) & 3, intsrc.mpc_srcbus, 
		intsrc.mpc_srcbusirq, intsrc.mpc_dstapic, intsrc.mpc_dstirq);

	mp_irqs[mp_irq_entries] = intsrc;
	if (++mp_irq_entries == MAX_IRQ_SOURCES)
		panic("Max # of irq sources exceeded!\n");

	return;
}


void __init mp_config_acpi_legacy_irqs (void)
{
	struct mpc_config_intsrc intsrc;
	int			i = 0;
	int			ioapic = -1;

	/* 
	 * Fabricate the legacy ISA bus (bus #31).
	 */
	mp_bus_id_to_type[MP_ISA_BUS] = MP_BUS_ISA;
	Dprintk("Bus #%d is ISA\n", MP_ISA_BUS);

	/* 
	 * Locate the IOAPIC that manages the ISA IRQs (0-15). 
	 */
	ioapic = mp_find_ioapic(0);
	if (ioapic < 0)
		return;

	intsrc.mpc_type = MP_INTSRC;
	intsrc.mpc_irqflag = 0;					/* Conforming */
	intsrc.mpc_srcbus = MP_ISA_BUS;
	intsrc.mpc_dstapic = mp_ioapics[ioapic].mpc_apicid;

	/* 
	 * Use the default configuration for the IRQs 0-15.  Unless
	 * overridden by (MADT) interrupt source override entries.
	 */
	for (i = 0; i < 16; i++) {
		int idx;

		for (idx = 0; idx < mp_irq_entries; idx++) {
			struct mpc_config_intsrc *irq = mp_irqs + idx;

			/* Do we already have a mapping for this ISA IRQ? */
			if (irq->mpc_srcbus == MP_ISA_BUS && irq->mpc_srcbusirq == i)
				break;

			/* Do we already have a mapping for this IOAPIC pin */
			if ((irq->mpc_dstapic == intsrc.mpc_dstapic) &&
				(irq->mpc_dstirq == i))
				break;
		}

		if (idx != mp_irq_entries) {
			printk(KERN_DEBUG "ACPI: IRQ%d used by override.\n", i);
			continue;			/* IRQ already used */
		}

		intsrc.mpc_irqtype = mp_INT;
		intsrc.mpc_srcbusirq = i;		   /* Identity mapped */
		intsrc.mpc_dstirq = i;

		Dprintk("Int: type %d, pol %d, trig %d, bus %d, irq %d, "
			"%d-%d\n", intsrc.mpc_irqtype, intsrc.mpc_irqflag & 3, 
			(intsrc.mpc_irqflag >> 2) & 3, intsrc.mpc_srcbus, 
			intsrc.mpc_srcbusirq, intsrc.mpc_dstapic, 
			intsrc.mpc_dstirq);

		mp_irqs[mp_irq_entries] = intsrc;
		if (++mp_irq_entries == MAX_IRQ_SOURCES)
			panic("Max # of irq sources exceeded!\n");
	}

	return;
}

#define MAX_GSI_NUM	4096

int mp_register_gsi(u32 gsi, int edge_level, int active_high_low)
{
	int			ioapic = -1;
	int			ioapic_pin = 0;
	int			idx, bit = 0;
	static int		pci_irq = 16;
	/*
	 * Mapping between Global System Interrupts, which
	 * represent all possible interrupts, to the IRQs
	 * assigned to actual devices.
	 */
	static int		gsi_to_irq[MAX_GSI_NUM];

	if (acpi_irq_model != ACPI_IRQ_MODEL_IOAPIC)
		return gsi;

	/* Don't set up the ACPI SCI because it's already set up */
	if (acpi_fadt.sci_int == gsi)
		return gsi;

	ioapic = mp_find_ioapic(gsi);
	if (ioapic < 0) {
		printk(KERN_WARNING "No IOAPIC for GSI %u\n", gsi);
		return gsi;
	}

	ioapic_pin = gsi - mp_ioapic_routing[ioapic].gsi_start;

	/* 
	 * Avoid pin reprogramming.  PRTs typically include entries  
	 * with redundant pin->gsi mappings (but unique PCI devices);
	 * we only program the IOAPIC on the first.
	 */
	bit = ioapic_pin % 32;
	idx = (ioapic_pin < 32) ? 0 : (ioapic_pin / 32);
	if (idx > 3) {
		printk(KERN_ERR "Invalid reference to IOAPIC pin "
			"%d-%d\n", mp_ioapic_routing[ioapic].apic_id, 
			ioapic_pin);
		return gsi;
	}
	if ((1<<bit) & mp_ioapic_routing[ioapic].pin_programmed[idx]) {
		Dprintk(KERN_DEBUG "Pin %d-%d already programmed\n",
			mp_ioapic_routing[ioapic].apic_id, ioapic_pin);
		return gsi_to_irq[gsi];
	}

	mp_ioapic_routing[ioapic].pin_programmed[idx] |= (1<<bit);

	if (edge_level) {
		/*
		 * For PCI devices assign IRQs in order, avoiding gaps
		 * due to unused I/O APIC pins.
		 */
		int irq = gsi;
		if (gsi < MAX_GSI_NUM) {
			if (gsi > 15)
				gsi = pci_irq++;
			/*
			 * Don't assign IRQ used by ACPI SCI
			 */
			if (gsi == acpi_fadt.sci_int)
				gsi = pci_irq++;
			gsi_to_irq[irq] = gsi;
		} else {
			printk(KERN_ERR "GSI %u is too high\n", gsi);
			return gsi;
		}
	}

	io_apic_set_pci_routing(ioapic, ioapic_pin, gsi,
		edge_level == ACPI_EDGE_SENSITIVE ? 0 : 1,
		active_high_low == ACPI_ACTIVE_HIGH ? 0 : 1);
	return gsi;
}

#endif /*CONFIG_X86_IO_APIC*/
#endif /*CONFIG_ACPI*/