1/*
2 *	Intel Multiprocessor Specification 1.1 and 1.4
3 *	compliant MP-table parsing routines.
4 *
5 *	(c) 1995 Alan Cox, Building #3 <alan@lxorguk.ukuu.org.uk>
6 *	(c) 1998, 1999, 2000, 2009 Ingo Molnar <mingo@redhat.com>
7 *      (c) 2008 Alexey Starikovskiy <astarikovskiy@suse.de>
8 */
9
10#include <linux/mm.h>
11#include <linux/init.h>
12#include <linux/delay.h>
13#include <linux/bootmem.h>
14#include <linux/memblock.h>
15#include <linux/kernel_stat.h>
16#include <linux/mc146818rtc.h>
17#include <linux/bitops.h>
18#include <linux/acpi.h>
19#include <linux/module.h>
20#include <linux/smp.h>
21#include <linux/pci.h>
22#include <linux/irqdomain.h>
23
24#include <asm/mtrr.h>
25#include <asm/mpspec.h>
26#include <asm/pgalloc.h>
27#include <asm/io_apic.h>
28#include <asm/proto.h>
29#include <asm/bios_ebda.h>
30#include <asm/e820.h>
31#include <asm/setup.h>
32#include <asm/smp.h>
33
34#include <asm/apic.h>
35/*
36 * Checksum an MP configuration block.
37 */
38
39static int __init mpf_checksum(unsigned char *mp, int len)
40{
41	int sum = 0;
42
43	while (len--)
44		sum += *mp++;
45
46	return sum & 0xFF;
47}
48
49int __init default_mpc_apic_id(struct mpc_cpu *m)
50{
51	return m->apicid;
52}
53
54static void __init MP_processor_info(struct mpc_cpu *m)
55{
56	int apicid;
57	char *bootup_cpu = "";
58
59	if (!(m->cpuflag & CPU_ENABLED)) {
60		disabled_cpus++;
61		return;
62	}
63
64	apicid = x86_init.mpparse.mpc_apic_id(m);
65
66	if (m->cpuflag & CPU_BOOTPROCESSOR) {
67		bootup_cpu = " (Bootup-CPU)";
68		boot_cpu_physical_apicid = m->apicid;
69	}
70
71	pr_info("Processor #%d%s\n", m->apicid, bootup_cpu);
72	generic_processor_info(apicid, m->apicver);
73}
74
75#ifdef CONFIG_X86_IO_APIC
76void __init default_mpc_oem_bus_info(struct mpc_bus *m, char *str)
77{
78	memcpy(str, m->bustype, 6);
79	str[6] = 0;
80	apic_printk(APIC_VERBOSE, "Bus #%d is %s\n", m->busid, str);
81}
82
83static void __init MP_bus_info(struct mpc_bus *m)
84{
85	char str[7];
86
87	x86_init.mpparse.mpc_oem_bus_info(m, str);
88
89#if MAX_MP_BUSSES < 256
90	if (m->busid >= MAX_MP_BUSSES) {
91		pr_warn("MP table busid value (%d) for bustype %s is too large, max. supported is %d\n",
92			m->busid, str, MAX_MP_BUSSES - 1);
93		return;
94	}
95#endif
96
97	set_bit(m->busid, mp_bus_not_pci);
98	if (strncmp(str, BUSTYPE_ISA, sizeof(BUSTYPE_ISA) - 1) == 0) {
99#ifdef CONFIG_EISA
100		mp_bus_id_to_type[m->busid] = MP_BUS_ISA;
101#endif
102	} else if (strncmp(str, BUSTYPE_PCI, sizeof(BUSTYPE_PCI) - 1) == 0) {
103		if (x86_init.mpparse.mpc_oem_pci_bus)
104			x86_init.mpparse.mpc_oem_pci_bus(m);
105
106		clear_bit(m->busid, mp_bus_not_pci);
107#ifdef CONFIG_EISA
108		mp_bus_id_to_type[m->busid] = MP_BUS_PCI;
109	} else if (strncmp(str, BUSTYPE_EISA, sizeof(BUSTYPE_EISA) - 1) == 0) {
110		mp_bus_id_to_type[m->busid] = MP_BUS_EISA;
111#endif
112	} else
113		pr_warn("Unknown bustype %s - ignoring\n", str);
114}
115
116static struct irq_domain_ops mp_ioapic_irqdomain_ops = {
117	.map = mp_irqdomain_map,
118	.unmap = mp_irqdomain_unmap,
119};
120
121static void __init MP_ioapic_info(struct mpc_ioapic *m)
122{
123	struct ioapic_domain_cfg cfg = {
124		.type = IOAPIC_DOMAIN_LEGACY,
125		.ops = &mp_ioapic_irqdomain_ops,
126	};
127
128	if (m->flags & MPC_APIC_USABLE)
129		mp_register_ioapic(m->apicid, m->apicaddr, gsi_top, &cfg);
130}
131
132static void __init print_mp_irq_info(struct mpc_intsrc *mp_irq)
133{
134	apic_printk(APIC_VERBOSE,
135		"Int: type %d, pol %d, trig %d, bus %02x, IRQ %02x, APIC ID %x, APIC INT %02x\n",
136		mp_irq->irqtype, mp_irq->irqflag & 3,
137		(mp_irq->irqflag >> 2) & 3, mp_irq->srcbus,
138		mp_irq->srcbusirq, mp_irq->dstapic, mp_irq->dstirq);
139}
140
141#else /* CONFIG_X86_IO_APIC */
142static inline void __init MP_bus_info(struct mpc_bus *m) {}
143static inline void __init MP_ioapic_info(struct mpc_ioapic *m) {}
144#endif /* CONFIG_X86_IO_APIC */
145
146static void __init MP_lintsrc_info(struct mpc_lintsrc *m)
147{
148	apic_printk(APIC_VERBOSE,
149		"Lint: type %d, pol %d, trig %d, bus %02x, IRQ %02x, APIC ID %x, APIC LINT %02x\n",
150		m->irqtype, m->irqflag & 3, (m->irqflag >> 2) & 3, m->srcbusid,
151		m->srcbusirq, m->destapic, m->destapiclint);
152}
153
154/*
155 * Read/parse the MPC
156 */
157static int __init smp_check_mpc(struct mpc_table *mpc, char *oem, char *str)
158{
159
160	if (memcmp(mpc->signature, MPC_SIGNATURE, 4)) {
161		pr_err("MPTABLE: bad signature [%c%c%c%c]!\n",
162		       mpc->signature[0], mpc->signature[1],
163		       mpc->signature[2], mpc->signature[3]);
164		return 0;
165	}
166	if (mpf_checksum((unsigned char *)mpc, mpc->length)) {
167		pr_err("MPTABLE: checksum error!\n");
168		return 0;
169	}
170	if (mpc->spec != 0x01 && mpc->spec != 0x04) {
171		pr_err("MPTABLE: bad table version (%d)!!\n", mpc->spec);
172		return 0;
173	}
174	if (!mpc->lapic) {
175		pr_err("MPTABLE: null local APIC address!\n");
176		return 0;
177	}
178	memcpy(oem, mpc->oem, 8);
179	oem[8] = 0;
180	pr_info("MPTABLE: OEM ID: %s\n", oem);
181
182	memcpy(str, mpc->productid, 12);
183	str[12] = 0;
184
185	pr_info("MPTABLE: Product ID: %s\n", str);
186
187	pr_info("MPTABLE: APIC at: 0x%X\n", mpc->lapic);
188
189	return 1;
190}
191
192static void skip_entry(unsigned char **ptr, int *count, int size)
193{
194	*ptr += size;
195	*count += size;
196}
197
198static void __init smp_dump_mptable(struct mpc_table *mpc, unsigned char *mpt)
199{
200	pr_err("Your mptable is wrong, contact your HW vendor!\n");
201	pr_cont("type %x\n", *mpt);
202	print_hex_dump(KERN_ERR, "  ", DUMP_PREFIX_ADDRESS, 16,
203			1, mpc, mpc->length, 1);
204}
205
206void __init default_smp_read_mpc_oem(struct mpc_table *mpc) { }
207
208static int __init smp_read_mpc(struct mpc_table *mpc, unsigned early)
209{
210	char str[16];
211	char oem[10];
212
213	int count = sizeof(*mpc);
214	unsigned char *mpt = ((unsigned char *)mpc) + count;
215
216	if (!smp_check_mpc(mpc, oem, str))
217		return 0;
218
219	/* Initialize the lapic mapping */
220	if (!acpi_lapic)
221		register_lapic_address(mpc->lapic);
222
223	if (early)
224		return 1;
225
226	if (mpc->oemptr)
227		x86_init.mpparse.smp_read_mpc_oem(mpc);
228
229	/*
230	 *      Now process the configuration blocks.
231	 */
232	x86_init.mpparse.mpc_record(0);
233
234	while (count < mpc->length) {
235		switch (*mpt) {
236		case MP_PROCESSOR:
237			/* ACPI may have already provided this data */
238			if (!acpi_lapic)
239				MP_processor_info((struct mpc_cpu *)mpt);
240			skip_entry(&mpt, &count, sizeof(struct mpc_cpu));
241			break;
242		case MP_BUS:
243			MP_bus_info((struct mpc_bus *)mpt);
244			skip_entry(&mpt, &count, sizeof(struct mpc_bus));
245			break;
246		case MP_IOAPIC:
247			MP_ioapic_info((struct mpc_ioapic *)mpt);
248			skip_entry(&mpt, &count, sizeof(struct mpc_ioapic));
249			break;
250		case MP_INTSRC:
251			mp_save_irq((struct mpc_intsrc *)mpt);
252			skip_entry(&mpt, &count, sizeof(struct mpc_intsrc));
253			break;
254		case MP_LINTSRC:
255			MP_lintsrc_info((struct mpc_lintsrc *)mpt);
256			skip_entry(&mpt, &count, sizeof(struct mpc_lintsrc));
257			break;
258		default:
259			/* wrong mptable */
260			smp_dump_mptable(mpc, mpt);
261			count = mpc->length;
262			break;
263		}
264		x86_init.mpparse.mpc_record(1);
265	}
266
267	if (!num_processors)
268		pr_err("MPTABLE: no processors registered!\n");
269	return num_processors;
270}
271
272#ifdef CONFIG_X86_IO_APIC
273
274static int __init ELCR_trigger(unsigned int irq)
275{
276	unsigned int port;
277
278	port = 0x4d0 + (irq >> 3);
279	return (inb(port) >> (irq & 7)) & 1;
280}
281
282static void __init construct_default_ioirq_mptable(int mpc_default_type)
283{
284	struct mpc_intsrc intsrc;
285	int i;
286	int ELCR_fallback = 0;
287
288	intsrc.type = MP_INTSRC;
289	intsrc.irqflag = 0;	/* conforming */
290	intsrc.srcbus = 0;
291	intsrc.dstapic = mpc_ioapic_id(0);
292
293	intsrc.irqtype = mp_INT;
294
295	/*
296	 *  If true, we have an ISA/PCI system with no IRQ entries
297	 *  in the MP table. To prevent the PCI interrupts from being set up
298	 *  incorrectly, we try to use the ELCR. The sanity check to see if
299	 *  there is good ELCR data is very simple - IRQ0, 1, 2 and 13 can
300	 *  never be level sensitive, so we simply see if the ELCR agrees.
301	 *  If it does, we assume it's valid.
302	 */
303	if (mpc_default_type == 5) {
304		pr_info("ISA/PCI bus type with no IRQ information... falling back to ELCR\n");
305
306		if (ELCR_trigger(0) || ELCR_trigger(1) || ELCR_trigger(2) ||
307		    ELCR_trigger(13))
308			pr_err("ELCR contains invalid data... not using ELCR\n");
309		else {
310			pr_info("Using ELCR to identify PCI interrupts\n");
311			ELCR_fallback = 1;
312		}
313	}
314
315	for (i = 0; i < 16; i++) {
316		switch (mpc_default_type) {
317		case 2:
318			if (i == 0 || i == 13)
319				continue;	/* IRQ0 & IRQ13 not connected */
320			/* fall through */
321		default:
322			if (i == 2)
323				continue;	/* IRQ2 is never connected */
324		}
325
326		if (ELCR_fallback) {
327			/*
328			 *  If the ELCR indicates a level-sensitive interrupt, we
329			 *  copy that information over to the MP table in the
330			 *  irqflag field (level sensitive, active high polarity).
331			 */
332			if (ELCR_trigger(i))
333				intsrc.irqflag = 13;
334			else
335				intsrc.irqflag = 0;
336		}
337
338		intsrc.srcbusirq = i;
339		intsrc.dstirq = i ? i : 2;	/* IRQ0 to INTIN2 */
340		mp_save_irq(&intsrc);
341	}
342
343	intsrc.irqtype = mp_ExtINT;
344	intsrc.srcbusirq = 0;
345	intsrc.dstirq = 0;	/* 8259A to INTIN0 */
346	mp_save_irq(&intsrc);
347}
348
349
350static void __init construct_ioapic_table(int mpc_default_type)
351{
352	struct mpc_ioapic ioapic;
353	struct mpc_bus bus;
354
355	bus.type = MP_BUS;
356	bus.busid = 0;
357	switch (mpc_default_type) {
358	default:
359		pr_err("???\nUnknown standard configuration %d\n",
360		       mpc_default_type);
361		/* fall through */
362	case 1:
363	case 5:
364		memcpy(bus.bustype, "ISA   ", 6);
365		break;
366	case 2:
367	case 6:
368	case 3:
369		memcpy(bus.bustype, "EISA  ", 6);
370		break;
371	}
372	MP_bus_info(&bus);
373	if (mpc_default_type > 4) {
374		bus.busid = 1;
375		memcpy(bus.bustype, "PCI   ", 6);
376		MP_bus_info(&bus);
377	}
378
379	ioapic.type	= MP_IOAPIC;
380	ioapic.apicid	= 2;
381	ioapic.apicver	= mpc_default_type > 4 ? 0x10 : 0x01;
382	ioapic.flags	= MPC_APIC_USABLE;
383	ioapic.apicaddr	= IO_APIC_DEFAULT_PHYS_BASE;
384	MP_ioapic_info(&ioapic);
385
386	/*
387	 * We set up most of the low 16 IO-APIC pins according to MPS rules.
388	 */
389	construct_default_ioirq_mptable(mpc_default_type);
390}
391#else
392static inline void __init construct_ioapic_table(int mpc_default_type) { }
393#endif
394
395static inline void __init construct_default_ISA_mptable(int mpc_default_type)
396{
397	struct mpc_cpu processor;
398	struct mpc_lintsrc lintsrc;
399	int linttypes[2] = { mp_ExtINT, mp_NMI };
400	int i;
401
402	/*
403	 * local APIC has default address
404	 */
405	mp_lapic_addr = APIC_DEFAULT_PHYS_BASE;
406
407	/*
408	 * 2 CPUs, numbered 0 & 1.
409	 */
410	processor.type = MP_PROCESSOR;
411	/* Either an integrated APIC or a discrete 82489DX. */
412	processor.apicver = mpc_default_type > 4 ? 0x10 : 0x01;
413	processor.cpuflag = CPU_ENABLED;
414	processor.cpufeature = (boot_cpu_data.x86 << 8) |
415	    (boot_cpu_data.x86_model << 4) | boot_cpu_data.x86_mask;
416	processor.featureflag = boot_cpu_data.x86_capability[0];
417	processor.reserved[0] = 0;
418	processor.reserved[1] = 0;
419	for (i = 0; i < 2; i++) {
420		processor.apicid = i;
421		MP_processor_info(&processor);
422	}
423
424	construct_ioapic_table(mpc_default_type);
425
426	lintsrc.type = MP_LINTSRC;
427	lintsrc.irqflag = 0;		/* conforming */
428	lintsrc.srcbusid = 0;
429	lintsrc.srcbusirq = 0;
430	lintsrc.destapic = MP_APIC_ALL;
431	for (i = 0; i < 2; i++) {
432		lintsrc.irqtype = linttypes[i];
433		lintsrc.destapiclint = i;
434		MP_lintsrc_info(&lintsrc);
435	}
436}
437
438static struct mpf_intel *mpf_found;
439
440static unsigned long __init get_mpc_size(unsigned long physptr)
441{
442	struct mpc_table *mpc;
443	unsigned long size;
444
445	mpc = early_ioremap(physptr, PAGE_SIZE);
446	size = mpc->length;
447	early_iounmap(mpc, PAGE_SIZE);
448	apic_printk(APIC_VERBOSE, "  mpc: %lx-%lx\n", physptr, physptr + size);
449
450	return size;
451}
452
453static int __init check_physptr(struct mpf_intel *mpf, unsigned int early)
454{
455	struct mpc_table *mpc;
456	unsigned long size;
457
458	size = get_mpc_size(mpf->physptr);
459	mpc = early_ioremap(mpf->physptr, size);
460	/*
461	 * Read the physical hardware table.  Anything here will
462	 * override the defaults.
463	 */
464	if (!smp_read_mpc(mpc, early)) {
465#ifdef CONFIG_X86_LOCAL_APIC
466		smp_found_config = 0;
467#endif
468		pr_err("BIOS bug, MP table errors detected!...\n");
469		pr_cont("... disabling SMP support. (tell your hw vendor)\n");
470		early_iounmap(mpc, size);
471		return -1;
472	}
473	early_iounmap(mpc, size);
474
475	if (early)
476		return -1;
477
478#ifdef CONFIG_X86_IO_APIC
479	/*
480	 * If there are no explicit MP IRQ entries, then we are
481	 * broken.  We set up most of the low 16 IO-APIC pins to
482	 * ISA defaults and hope it will work.
483	 */
484	if (!mp_irq_entries) {
485		struct mpc_bus bus;
486
487		pr_err("BIOS bug, no explicit IRQ entries, using default mptable. (tell your hw vendor)\n");
488
489		bus.type = MP_BUS;
490		bus.busid = 0;
491		memcpy(bus.bustype, "ISA   ", 6);
492		MP_bus_info(&bus);
493
494		construct_default_ioirq_mptable(0);
495	}
496#endif
497
498	return 0;
499}
500
501/*
502 * Scan the memory blocks for an SMP configuration block.
503 */
504void __init default_get_smp_config(unsigned int early)
505{
506	struct mpf_intel *mpf = mpf_found;
507
508	if (!mpf)
509		return;
510
511	if (acpi_lapic && early)
512		return;
513
514	/*
515	 * MPS doesn't support hyperthreading, aka only have
516	 * thread 0 apic id in MPS table
517	 */
518	if (acpi_lapic && acpi_ioapic)
519		return;
520
521	pr_info("Intel MultiProcessor Specification v1.%d\n",
522		mpf->specification);
523#if defined(CONFIG_X86_LOCAL_APIC) && defined(CONFIG_X86_32)
524	if (mpf->feature2 & (1 << 7)) {
525		pr_info("    IMCR and PIC compatibility mode.\n");
526		pic_mode = 1;
527	} else {
528		pr_info("    Virtual Wire compatibility mode.\n");
529		pic_mode = 0;
530	}
531#endif
532	/*
533	 * Now see if we need to read further.
534	 */
535	if (mpf->feature1 != 0) {
536		if (early) {
537			/*
538			 * local APIC has default address
539			 */
540			mp_lapic_addr = APIC_DEFAULT_PHYS_BASE;
541			return;
542		}
543
544		pr_info("Default MP configuration #%d\n", mpf->feature1);
545		construct_default_ISA_mptable(mpf->feature1);
546
547	} else if (mpf->physptr) {
548		if (check_physptr(mpf, early))
549			return;
550	} else
551		BUG();
552
553	if (!early)
554		pr_info("Processors: %d\n", num_processors);
555	/*
556	 * Only use the first configuration found.
557	 */
558}
559
560static void __init smp_reserve_memory(struct mpf_intel *mpf)
561{
562	memblock_reserve(mpf->physptr, get_mpc_size(mpf->physptr));
563}
564
565static int __init smp_scan_config(unsigned long base, unsigned long length)
566{
567	unsigned int *bp = phys_to_virt(base);
568	struct mpf_intel *mpf;
569	unsigned long mem;
570
571	apic_printk(APIC_VERBOSE, "Scan for SMP in [mem %#010lx-%#010lx]\n",
572		    base, base + length - 1);
573	BUILD_BUG_ON(sizeof(*mpf) != 16);
574
575	while (length > 0) {
576		mpf = (struct mpf_intel *)bp;
577		if ((*bp == SMP_MAGIC_IDENT) &&
578		    (mpf->length == 1) &&
579		    !mpf_checksum((unsigned char *)bp, 16) &&
580		    ((mpf->specification == 1)
581		     || (mpf->specification == 4))) {
582#ifdef CONFIG_X86_LOCAL_APIC
583			smp_found_config = 1;
584#endif
585			mpf_found = mpf;
586
587			pr_info("found SMP MP-table at [mem %#010llx-%#010llx] mapped at [%p]\n",
588				(unsigned long long) virt_to_phys(mpf),
589				(unsigned long long) virt_to_phys(mpf) +
590				sizeof(*mpf) - 1, mpf);
591
592			mem = virt_to_phys(mpf);
593			memblock_reserve(mem, sizeof(*mpf));
594			if (mpf->physptr)
595				smp_reserve_memory(mpf);
596
597			return 1;
598		}
599		bp += 4;
600		length -= 16;
601	}
602	return 0;
603}
604
605void __init default_find_smp_config(void)
606{
607	unsigned int address;
608
609	/*
610	 * FIXME: Linux assumes you have 640K of base ram..
611	 * this continues the error...
612	 *
613	 * 1) Scan the bottom 1K for a signature
614	 * 2) Scan the top 1K of base RAM
615	 * 3) Scan the 64K of bios
616	 */
617	if (smp_scan_config(0x0, 0x400) ||
618	    smp_scan_config(639 * 0x400, 0x400) ||
619	    smp_scan_config(0xF0000, 0x10000))
620		return;
621	/*
622	 * If it is an SMP machine we should know now, unless the
623	 * configuration is in an EISA bus machine with an
624	 * extended bios data area.
625	 *
626	 * there is a real-mode segmented pointer pointing to the
627	 * 4K EBDA area at 0x40E, calculate and scan it here.
628	 *
629	 * NOTE! There are Linux loaders that will corrupt the EBDA
630	 * area, and as such this kind of SMP config may be less
631	 * trustworthy, simply because the SMP table may have been
632	 * stomped on during early boot. These loaders are buggy and
633	 * should be fixed.
634	 *
635	 * MP1.4 SPEC states to only scan first 1K of 4K EBDA.
636	 */
637
638	address = get_bios_ebda();
639	if (address)
640		smp_scan_config(address, 0x400);
641}
642
643#ifdef CONFIG_X86_IO_APIC
644static u8 __initdata irq_used[MAX_IRQ_SOURCES];
645
646static int  __init get_MP_intsrc_index(struct mpc_intsrc *m)
647{
648	int i;
649
650	if (m->irqtype != mp_INT)
651		return 0;
652
653	if (m->irqflag != 0x0f)
654		return 0;
655
656	/* not legacy */
657
658	for (i = 0; i < mp_irq_entries; i++) {
659		if (mp_irqs[i].irqtype != mp_INT)
660			continue;
661
662		if (mp_irqs[i].irqflag != 0x0f)
663			continue;
664
665		if (mp_irqs[i].srcbus != m->srcbus)
666			continue;
667		if (mp_irqs[i].srcbusirq != m->srcbusirq)
668			continue;
669		if (irq_used[i]) {
670			/* already claimed */
671			return -2;
672		}
673		irq_used[i] = 1;
674		return i;
675	}
676
677	/* not found */
678	return -1;
679}
680
681#define SPARE_SLOT_NUM 20
682
683static struct mpc_intsrc __initdata *m_spare[SPARE_SLOT_NUM];
684
685static void __init check_irq_src(struct mpc_intsrc *m, int *nr_m_spare)
686{
687	int i;
688
689	apic_printk(APIC_VERBOSE, "OLD ");
690	print_mp_irq_info(m);
691
692	i = get_MP_intsrc_index(m);
693	if (i > 0) {
694		memcpy(m, &mp_irqs[i], sizeof(*m));
695		apic_printk(APIC_VERBOSE, "NEW ");
696		print_mp_irq_info(&mp_irqs[i]);
697		return;
698	}
699	if (!i) {
700		/* legacy, do nothing */
701		return;
702	}
703	if (*nr_m_spare < SPARE_SLOT_NUM) {
704		/*
705		 * not found (-1), or duplicated (-2) are invalid entries,
706		 * we need to use the slot later
707		 */
708		m_spare[*nr_m_spare] = m;
709		*nr_m_spare += 1;
710	}
711}
712
713static int __init
714check_slot(unsigned long mpc_new_phys, unsigned long mpc_new_length, int count)
715{
716	if (!mpc_new_phys || count <= mpc_new_length) {
717		WARN(1, "update_mptable: No spare slots (length: %x)\n", count);
718		return -1;
719	}
720
721	return 0;
722}
723#else /* CONFIG_X86_IO_APIC */
724static
725inline void __init check_irq_src(struct mpc_intsrc *m, int *nr_m_spare) {}
726#endif /* CONFIG_X86_IO_APIC */
727
728static int  __init replace_intsrc_all(struct mpc_table *mpc,
729					unsigned long mpc_new_phys,
730					unsigned long mpc_new_length)
731{
732#ifdef CONFIG_X86_IO_APIC
733	int i;
734#endif
735	int count = sizeof(*mpc);
736	int nr_m_spare = 0;
737	unsigned char *mpt = ((unsigned char *)mpc) + count;
738
739	pr_info("mpc_length %x\n", mpc->length);
740	while (count < mpc->length) {
741		switch (*mpt) {
742		case MP_PROCESSOR:
743			skip_entry(&mpt, &count, sizeof(struct mpc_cpu));
744			break;
745		case MP_BUS:
746			skip_entry(&mpt, &count, sizeof(struct mpc_bus));
747			break;
748		case MP_IOAPIC:
749			skip_entry(&mpt, &count, sizeof(struct mpc_ioapic));
750			break;
751		case MP_INTSRC:
752			check_irq_src((struct mpc_intsrc *)mpt, &nr_m_spare);
753			skip_entry(&mpt, &count, sizeof(struct mpc_intsrc));
754			break;
755		case MP_LINTSRC:
756			skip_entry(&mpt, &count, sizeof(struct mpc_lintsrc));
757			break;
758		default:
759			/* wrong mptable */
760			smp_dump_mptable(mpc, mpt);
761			goto out;
762		}
763	}
764
765#ifdef CONFIG_X86_IO_APIC
766	for (i = 0; i < mp_irq_entries; i++) {
767		if (irq_used[i])
768			continue;
769
770		if (mp_irqs[i].irqtype != mp_INT)
771			continue;
772
773		if (mp_irqs[i].irqflag != 0x0f)
774			continue;
775
776		if (nr_m_spare > 0) {
777			apic_printk(APIC_VERBOSE, "*NEW* found\n");
778			nr_m_spare--;
779			memcpy(m_spare[nr_m_spare], &mp_irqs[i], sizeof(mp_irqs[i]));
780			m_spare[nr_m_spare] = NULL;
781		} else {
782			struct mpc_intsrc *m = (struct mpc_intsrc *)mpt;
783			count += sizeof(struct mpc_intsrc);
784			if (check_slot(mpc_new_phys, mpc_new_length, count) < 0)
785				goto out;
786			memcpy(m, &mp_irqs[i], sizeof(*m));
787			mpc->length = count;
788			mpt += sizeof(struct mpc_intsrc);
789		}
790		print_mp_irq_info(&mp_irqs[i]);
791	}
792#endif
793out:
794	/* update checksum */
795	mpc->checksum = 0;
796	mpc->checksum -= mpf_checksum((unsigned char *)mpc, mpc->length);
797
798	return 0;
799}
800
801int enable_update_mptable;
802
803static int __init update_mptable_setup(char *str)
804{
805	enable_update_mptable = 1;
806#ifdef CONFIG_PCI
807	pci_routeirq = 1;
808#endif
809	return 0;
810}
811early_param("update_mptable", update_mptable_setup);
812
813static unsigned long __initdata mpc_new_phys;
814static unsigned long mpc_new_length __initdata = 4096;
815
816/* alloc_mptable or alloc_mptable=4k */
817static int __initdata alloc_mptable;
818static int __init parse_alloc_mptable_opt(char *p)
819{
820	enable_update_mptable = 1;
821#ifdef CONFIG_PCI
822	pci_routeirq = 1;
823#endif
824	alloc_mptable = 1;
825	if (!p)
826		return 0;
827	mpc_new_length = memparse(p, &p);
828	return 0;
829}
830early_param("alloc_mptable", parse_alloc_mptable_opt);
831
832void __init early_reserve_e820_mpc_new(void)
833{
834	if (enable_update_mptable && alloc_mptable)
835		mpc_new_phys = early_reserve_e820(mpc_new_length, 4);
836}
837
838static int __init update_mp_table(void)
839{
840	char str[16];
841	char oem[10];
842	struct mpf_intel *mpf;
843	struct mpc_table *mpc, *mpc_new;
844
845	if (!enable_update_mptable)
846		return 0;
847
848	mpf = mpf_found;
849	if (!mpf)
850		return 0;
851
852	/*
853	 * Now see if we need to go further.
854	 */
855	if (mpf->feature1 != 0)
856		return 0;
857
858	if (!mpf->physptr)
859		return 0;
860
861	mpc = phys_to_virt(mpf->physptr);
862
863	if (!smp_check_mpc(mpc, oem, str))
864		return 0;
865
866	pr_info("mpf: %llx\n", (u64)virt_to_phys(mpf));
867	pr_info("physptr: %x\n", mpf->physptr);
868
869	if (mpc_new_phys && mpc->length > mpc_new_length) {
870		mpc_new_phys = 0;
871		pr_info("mpc_new_length is %ld, please use alloc_mptable=8k\n",
872			mpc_new_length);
873	}
874
875	if (!mpc_new_phys) {
876		unsigned char old, new;
877		/* check if we can change the position */
878		mpc->checksum = 0;
879		old = mpf_checksum((unsigned char *)mpc, mpc->length);
880		mpc->checksum = 0xff;
881		new = mpf_checksum((unsigned char *)mpc, mpc->length);
882		if (old == new) {
883			pr_info("mpc is readonly, please try alloc_mptable instead\n");
884			return 0;
885		}
886		pr_info("use in-position replacing\n");
887	} else {
888		mpf->physptr = mpc_new_phys;
889		mpc_new = phys_to_virt(mpc_new_phys);
890		memcpy(mpc_new, mpc, mpc->length);
891		mpc = mpc_new;
892		/* check if we can modify that */
893		if (mpc_new_phys - mpf->physptr) {
894			struct mpf_intel *mpf_new;
895			/* steal 16 bytes from [0, 1k) */
896			pr_info("mpf new: %x\n", 0x400 - 16);
897			mpf_new = phys_to_virt(0x400 - 16);
898			memcpy(mpf_new, mpf, 16);
899			mpf = mpf_new;
900			mpf->physptr = mpc_new_phys;
901		}
902		mpf->checksum = 0;
903		mpf->checksum -= mpf_checksum((unsigned char *)mpf, 16);
904		pr_info("physptr new: %x\n", mpf->physptr);
905	}
906
907	/*
908	 * only replace the one with mp_INT and
909	 *	 MP_IRQ_TRIGGER_LEVEL|MP_IRQ_POLARITY_LOW,
910	 * already in mp_irqs , stored by ... and mp_config_acpi_gsi,
911	 * may need pci=routeirq for all coverage
912	 */
913	replace_intsrc_all(mpc, mpc_new_phys, mpc_new_length);
914
915	return 0;
916}
917
918late_initcall(update_mp_table);
919