xref: /linux/arch/x86/kernel/mpparse.c (revision 5bdef865eb358b6f3760e25e591ae115e9eeddef)
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/kernel_stat.h>
15 #include <linux/mc146818rtc.h>
16 #include <linux/bitops.h>
17 #include <linux/acpi.h>
18 #include <linux/module.h>
19 #include <linux/smp.h>
20 #include <linux/pci.h>
21 
22 #include <asm/mtrr.h>
23 #include <asm/mpspec.h>
24 #include <asm/pgalloc.h>
25 #include <asm/io_apic.h>
26 #include <asm/proto.h>
27 #include <asm/bios_ebda.h>
28 #include <asm/e820.h>
29 #include <asm/trampoline.h>
30 #include <asm/setup.h>
31 #include <asm/smp.h>
32 
33 #include <asm/apic.h>
34 /*
35  * Checksum an MP configuration block.
36  */
37 
38 static int __init mpf_checksum(unsigned char *mp, int len)
39 {
40 	int sum = 0;
41 
42 	while (len--)
43 		sum += *mp++;
44 
45 	return sum & 0xFF;
46 }
47 
48 static void __init MP_processor_info(struct mpc_cpu *m)
49 {
50 	int apicid;
51 	char *bootup_cpu = "";
52 
53 	if (!(m->cpuflag & CPU_ENABLED)) {
54 		disabled_cpus++;
55 		return;
56 	}
57 
58 	if (x86_quirks->mpc_apic_id)
59 		apicid = x86_quirks->mpc_apic_id(m);
60 	else
61 		apicid = m->apicid;
62 
63 	if (m->cpuflag & CPU_BOOTPROCESSOR) {
64 		bootup_cpu = " (Bootup-CPU)";
65 		boot_cpu_physical_apicid = m->apicid;
66 	}
67 
68 	printk(KERN_INFO "Processor #%d%s\n", m->apicid, bootup_cpu);
69 	generic_processor_info(apicid, m->apicver);
70 }
71 
72 #ifdef CONFIG_X86_IO_APIC
73 static void __init MP_bus_info(struct mpc_bus *m)
74 {
75 	char str[7];
76 	memcpy(str, m->bustype, 6);
77 	str[6] = 0;
78 
79 	if (x86_quirks->mpc_oem_bus_info)
80 		x86_quirks->mpc_oem_bus_info(m, str);
81 	else
82 		apic_printk(APIC_VERBOSE, "Bus #%d is %s\n", m->busid, str);
83 
84 #if MAX_MP_BUSSES < 256
85 	if (m->busid >= MAX_MP_BUSSES) {
86 		printk(KERN_WARNING "MP table busid value (%d) for bustype %s "
87 		       " is too large, max. supported is %d\n",
88 		       m->busid, str, MAX_MP_BUSSES - 1);
89 		return;
90 	}
91 #endif
92 
93 	if (strncmp(str, BUSTYPE_ISA, sizeof(BUSTYPE_ISA) - 1) == 0) {
94 		set_bit(m->busid, mp_bus_not_pci);
95 #if defined(CONFIG_EISA) || defined(CONFIG_MCA)
96 		mp_bus_id_to_type[m->busid] = MP_BUS_ISA;
97 #endif
98 	} else if (strncmp(str, BUSTYPE_PCI, sizeof(BUSTYPE_PCI) - 1) == 0) {
99 		if (x86_quirks->mpc_oem_pci_bus)
100 			x86_quirks->mpc_oem_pci_bus(m);
101 
102 		clear_bit(m->busid, mp_bus_not_pci);
103 #if defined(CONFIG_EISA) || defined(CONFIG_MCA)
104 		mp_bus_id_to_type[m->busid] = MP_BUS_PCI;
105 	} else if (strncmp(str, BUSTYPE_EISA, sizeof(BUSTYPE_EISA) - 1) == 0) {
106 		mp_bus_id_to_type[m->busid] = MP_BUS_EISA;
107 	} else if (strncmp(str, BUSTYPE_MCA, sizeof(BUSTYPE_MCA) - 1) == 0) {
108 		mp_bus_id_to_type[m->busid] = MP_BUS_MCA;
109 #endif
110 	} else
111 		printk(KERN_WARNING "Unknown bustype %s - ignoring\n", str);
112 }
113 
114 static int bad_ioapic(unsigned long address)
115 {
116 	if (nr_ioapics >= MAX_IO_APICS) {
117 		printk(KERN_ERR "ERROR: Max # of I/O APICs (%d) exceeded "
118 		       "(found %d)\n", MAX_IO_APICS, nr_ioapics);
119 		panic("Recompile kernel with bigger MAX_IO_APICS!\n");
120 	}
121 	if (!address) {
122 		printk(KERN_ERR "WARNING: Bogus (zero) I/O APIC address"
123 		       " found in table, skipping!\n");
124 		return 1;
125 	}
126 	return 0;
127 }
128 
129 static void __init MP_ioapic_info(struct mpc_ioapic *m)
130 {
131 	if (!(m->flags & MPC_APIC_USABLE))
132 		return;
133 
134 	printk(KERN_INFO "I/O APIC #%d Version %d at 0x%X.\n",
135 	       m->apicid, m->apicver, m->apicaddr);
136 
137 	if (bad_ioapic(m->apicaddr))
138 		return;
139 
140 	mp_ioapics[nr_ioapics].apicaddr = m->apicaddr;
141 	mp_ioapics[nr_ioapics].apicid = m->apicid;
142 	mp_ioapics[nr_ioapics].type = m->type;
143 	mp_ioapics[nr_ioapics].apicver = m->apicver;
144 	mp_ioapics[nr_ioapics].flags = m->flags;
145 	nr_ioapics++;
146 }
147 
148 static void print_MP_intsrc_info(struct mpc_intsrc *m)
149 {
150 	apic_printk(APIC_VERBOSE, "Int: type %d, pol %d, trig %d, bus %02x,"
151 		" IRQ %02x, APIC ID %x, APIC INT %02x\n",
152 		m->irqtype, m->irqflag & 3, (m->irqflag >> 2) & 3, m->srcbus,
153 		m->srcbusirq, m->dstapic, m->dstirq);
154 }
155 
156 static void __init print_mp_irq_info(struct mpc_intsrc *mp_irq)
157 {
158 	apic_printk(APIC_VERBOSE, "Int: type %d, pol %d, trig %d, bus %02x,"
159 		" IRQ %02x, APIC ID %x, APIC INT %02x\n",
160 		mp_irq->irqtype, mp_irq->irqflag & 3,
161 		(mp_irq->irqflag >> 2) & 3, mp_irq->srcbus,
162 		mp_irq->srcbusirq, mp_irq->dstapic, mp_irq->dstirq);
163 }
164 
165 static void __init assign_to_mp_irq(struct mpc_intsrc *m,
166 				    struct mpc_intsrc *mp_irq)
167 {
168 	mp_irq->dstapic = m->dstapic;
169 	mp_irq->type = m->type;
170 	mp_irq->irqtype = m->irqtype;
171 	mp_irq->irqflag = m->irqflag;
172 	mp_irq->srcbus = m->srcbus;
173 	mp_irq->srcbusirq = m->srcbusirq;
174 	mp_irq->dstirq = m->dstirq;
175 }
176 
177 static void __init assign_to_mpc_intsrc(struct mpc_intsrc *mp_irq,
178 					struct mpc_intsrc *m)
179 {
180 	m->dstapic = mp_irq->dstapic;
181 	m->type = mp_irq->type;
182 	m->irqtype = mp_irq->irqtype;
183 	m->irqflag = mp_irq->irqflag;
184 	m->srcbus = mp_irq->srcbus;
185 	m->srcbusirq = mp_irq->srcbusirq;
186 	m->dstirq = mp_irq->dstirq;
187 }
188 
189 static int __init mp_irq_mpc_intsrc_cmp(struct mpc_intsrc *mp_irq,
190 					struct mpc_intsrc *m)
191 {
192 	if (mp_irq->dstapic != m->dstapic)
193 		return 1;
194 	if (mp_irq->type != m->type)
195 		return 2;
196 	if (mp_irq->irqtype != m->irqtype)
197 		return 3;
198 	if (mp_irq->irqflag != m->irqflag)
199 		return 4;
200 	if (mp_irq->srcbus != m->srcbus)
201 		return 5;
202 	if (mp_irq->srcbusirq != m->srcbusirq)
203 		return 6;
204 	if (mp_irq->dstirq != m->dstirq)
205 		return 7;
206 
207 	return 0;
208 }
209 
210 static void __init MP_intsrc_info(struct mpc_intsrc *m)
211 {
212 	int i;
213 
214 	print_MP_intsrc_info(m);
215 
216 	for (i = 0; i < mp_irq_entries; i++) {
217 		if (!mp_irq_mpc_intsrc_cmp(&mp_irqs[i], m))
218 			return;
219 	}
220 
221 	assign_to_mp_irq(m, &mp_irqs[mp_irq_entries]);
222 	if (++mp_irq_entries == MAX_IRQ_SOURCES)
223 		panic("Max # of irq sources exceeded!!\n");
224 }
225 #else /* CONFIG_X86_IO_APIC */
226 static inline void __init MP_bus_info(struct mpc_bus *m) {}
227 static inline void __init MP_ioapic_info(struct mpc_ioapic *m) {}
228 static inline void __init MP_intsrc_info(struct mpc_intsrc *m) {}
229 #endif /* CONFIG_X86_IO_APIC */
230 
231 
232 static void __init MP_lintsrc_info(struct mpc_lintsrc *m)
233 {
234 	apic_printk(APIC_VERBOSE, "Lint: type %d, pol %d, trig %d, bus %02x,"
235 		" IRQ %02x, APIC ID %x, APIC LINT %02x\n",
236 		m->irqtype, m->irqflag & 3, (m->irqflag >> 2) & 3, m->srcbusid,
237 		m->srcbusirq, m->destapic, m->destapiclint);
238 }
239 
240 /*
241  * Read/parse the MPC
242  */
243 
244 static int __init smp_check_mpc(struct mpc_table *mpc, char *oem, char *str)
245 {
246 
247 	if (memcmp(mpc->signature, MPC_SIGNATURE, 4)) {
248 		printk(KERN_ERR "MPTABLE: bad signature [%c%c%c%c]!\n",
249 		       mpc->signature[0], mpc->signature[1],
250 		       mpc->signature[2], mpc->signature[3]);
251 		return 0;
252 	}
253 	if (mpf_checksum((unsigned char *)mpc, mpc->length)) {
254 		printk(KERN_ERR "MPTABLE: checksum error!\n");
255 		return 0;
256 	}
257 	if (mpc->spec != 0x01 && mpc->spec != 0x04) {
258 		printk(KERN_ERR "MPTABLE: bad table version (%d)!!\n",
259 		       mpc->spec);
260 		return 0;
261 	}
262 	if (!mpc->lapic) {
263 		printk(KERN_ERR "MPTABLE: null local APIC address!\n");
264 		return 0;
265 	}
266 	memcpy(oem, mpc->oem, 8);
267 	oem[8] = 0;
268 	printk(KERN_INFO "MPTABLE: OEM ID: %s\n", oem);
269 
270 	memcpy(str, mpc->productid, 12);
271 	str[12] = 0;
272 
273 	printk(KERN_INFO "MPTABLE: Product ID: %s\n", str);
274 
275 	printk(KERN_INFO "MPTABLE: APIC at: 0x%X\n", mpc->lapic);
276 
277 	return 1;
278 }
279 
280 static void skip_entry(unsigned char **ptr, int *count, int size)
281 {
282 	*ptr += size;
283 	*count += size;
284 }
285 
286 static void __init smp_dump_mptable(struct mpc_table *mpc, unsigned char *mpt)
287 {
288 	printk(KERN_ERR "Your mptable is wrong, contact your HW vendor!\n"
289 		"type %x\n", *mpt);
290 	print_hex_dump(KERN_ERR, "  ", DUMP_PREFIX_ADDRESS, 16,
291 			1, mpc, mpc->length, 1);
292 }
293 
294 static int __init smp_read_mpc(struct mpc_table *mpc, unsigned early)
295 {
296 	char str[16];
297 	char oem[10];
298 
299 	int count = sizeof(*mpc);
300 	unsigned char *mpt = ((unsigned char *)mpc) + count;
301 
302 	if (!smp_check_mpc(mpc, oem, str))
303 		return 0;
304 
305 #ifdef CONFIG_X86_32
306 	generic_mps_oem_check(mpc, oem, str);
307 #endif
308 	/* save the local APIC address, it might be non-default */
309 	if (!acpi_lapic)
310 		mp_lapic_addr = mpc->lapic;
311 
312 	if (early)
313 		return 1;
314 
315 	if (mpc->oemptr && x86_quirks->smp_read_mpc_oem) {
316 		struct mpc_oemtable *oem_table = (void *)(long)mpc->oemptr;
317 		x86_quirks->smp_read_mpc_oem(oem_table, mpc->oemsize);
318 	}
319 
320 	/*
321 	 *      Now process the configuration blocks.
322 	 */
323 	if (x86_quirks->mpc_record)
324 		*x86_quirks->mpc_record = 0;
325 
326 	while (count < mpc->length) {
327 		switch (*mpt) {
328 		case MP_PROCESSOR:
329 			/* ACPI may have already provided this data */
330 			if (!acpi_lapic)
331 				MP_processor_info((struct mpc_cpu *)mpt);
332 			skip_entry(&mpt, &count, sizeof(struct mpc_cpu));
333 			break;
334 		case MP_BUS:
335 			MP_bus_info((struct mpc_bus *)mpt);
336 			skip_entry(&mpt, &count, sizeof(struct mpc_bus));
337 			break;
338 		case MP_IOAPIC:
339 			MP_ioapic_info((struct mpc_ioapic *)mpt);
340 			skip_entry(&mpt, &count, sizeof(struct mpc_ioapic));
341 			break;
342 		case MP_INTSRC:
343 			MP_intsrc_info((struct mpc_intsrc *)mpt);
344 			skip_entry(&mpt, &count, sizeof(struct mpc_intsrc));
345 			break;
346 		case MP_LINTSRC:
347 			MP_lintsrc_info((struct mpc_lintsrc *)mpt);
348 			skip_entry(&mpt, &count, sizeof(struct mpc_lintsrc));
349 			break;
350 		default:
351 			/* wrong mptable */
352 			smp_dump_mptable(mpc, mpt);
353 			count = mpc->length;
354 			break;
355 		}
356 		if (x86_quirks->mpc_record)
357 			(*x86_quirks->mpc_record)++;
358 	}
359 
360 #ifdef CONFIG_X86_BIGSMP
361 	generic_bigsmp_probe();
362 #endif
363 
364 	if (apic->setup_apic_routing)
365 		apic->setup_apic_routing();
366 
367 	if (!num_processors)
368 		printk(KERN_ERR "MPTABLE: no processors registered!\n");
369 	return num_processors;
370 }
371 
372 #ifdef CONFIG_X86_IO_APIC
373 
374 static int __init ELCR_trigger(unsigned int irq)
375 {
376 	unsigned int port;
377 
378 	port = 0x4d0 + (irq >> 3);
379 	return (inb(port) >> (irq & 7)) & 1;
380 }
381 
382 static void __init construct_default_ioirq_mptable(int mpc_default_type)
383 {
384 	struct mpc_intsrc intsrc;
385 	int i;
386 	int ELCR_fallback = 0;
387 
388 	intsrc.type = MP_INTSRC;
389 	intsrc.irqflag = 0;	/* conforming */
390 	intsrc.srcbus = 0;
391 	intsrc.dstapic = mp_ioapics[0].apicid;
392 
393 	intsrc.irqtype = mp_INT;
394 
395 	/*
396 	 *  If true, we have an ISA/PCI system with no IRQ entries
397 	 *  in the MP table. To prevent the PCI interrupts from being set up
398 	 *  incorrectly, we try to use the ELCR. The sanity check to see if
399 	 *  there is good ELCR data is very simple - IRQ0, 1, 2 and 13 can
400 	 *  never be level sensitive, so we simply see if the ELCR agrees.
401 	 *  If it does, we assume it's valid.
402 	 */
403 	if (mpc_default_type == 5) {
404 		printk(KERN_INFO "ISA/PCI bus type with no IRQ information... "
405 		       "falling back to ELCR\n");
406 
407 		if (ELCR_trigger(0) || ELCR_trigger(1) || ELCR_trigger(2) ||
408 		    ELCR_trigger(13))
409 			printk(KERN_ERR "ELCR contains invalid data... "
410 			       "not using ELCR\n");
411 		else {
412 			printk(KERN_INFO
413 			       "Using ELCR to identify PCI interrupts\n");
414 			ELCR_fallback = 1;
415 		}
416 	}
417 
418 	for (i = 0; i < 16; i++) {
419 		switch (mpc_default_type) {
420 		case 2:
421 			if (i == 0 || i == 13)
422 				continue;	/* IRQ0 & IRQ13 not connected */
423 			/* fall through */
424 		default:
425 			if (i == 2)
426 				continue;	/* IRQ2 is never connected */
427 		}
428 
429 		if (ELCR_fallback) {
430 			/*
431 			 *  If the ELCR indicates a level-sensitive interrupt, we
432 			 *  copy that information over to the MP table in the
433 			 *  irqflag field (level sensitive, active high polarity).
434 			 */
435 			if (ELCR_trigger(i))
436 				intsrc.irqflag = 13;
437 			else
438 				intsrc.irqflag = 0;
439 		}
440 
441 		intsrc.srcbusirq = i;
442 		intsrc.dstirq = i ? i : 2;	/* IRQ0 to INTIN2 */
443 		MP_intsrc_info(&intsrc);
444 	}
445 
446 	intsrc.irqtype = mp_ExtINT;
447 	intsrc.srcbusirq = 0;
448 	intsrc.dstirq = 0;	/* 8259A to INTIN0 */
449 	MP_intsrc_info(&intsrc);
450 }
451 
452 
453 static void __init construct_ioapic_table(int mpc_default_type)
454 {
455 	struct mpc_ioapic ioapic;
456 	struct mpc_bus bus;
457 
458 	bus.type = MP_BUS;
459 	bus.busid = 0;
460 	switch (mpc_default_type) {
461 	default:
462 		printk(KERN_ERR "???\nUnknown standard configuration %d\n",
463 		       mpc_default_type);
464 		/* fall through */
465 	case 1:
466 	case 5:
467 		memcpy(bus.bustype, "ISA   ", 6);
468 		break;
469 	case 2:
470 	case 6:
471 	case 3:
472 		memcpy(bus.bustype, "EISA  ", 6);
473 		break;
474 	case 4:
475 	case 7:
476 		memcpy(bus.bustype, "MCA   ", 6);
477 	}
478 	MP_bus_info(&bus);
479 	if (mpc_default_type > 4) {
480 		bus.busid = 1;
481 		memcpy(bus.bustype, "PCI   ", 6);
482 		MP_bus_info(&bus);
483 	}
484 
485 	ioapic.type = MP_IOAPIC;
486 	ioapic.apicid = 2;
487 	ioapic.apicver = mpc_default_type > 4 ? 0x10 : 0x01;
488 	ioapic.flags = MPC_APIC_USABLE;
489 	ioapic.apicaddr = 0xFEC00000;
490 	MP_ioapic_info(&ioapic);
491 
492 	/*
493 	 * We set up most of the low 16 IO-APIC pins according to MPS rules.
494 	 */
495 	construct_default_ioirq_mptable(mpc_default_type);
496 }
497 #else
498 static inline void __init construct_ioapic_table(int mpc_default_type) { }
499 #endif
500 
501 static inline void __init construct_default_ISA_mptable(int mpc_default_type)
502 {
503 	struct mpc_cpu processor;
504 	struct mpc_lintsrc lintsrc;
505 	int linttypes[2] = { mp_ExtINT, mp_NMI };
506 	int i;
507 
508 	/*
509 	 * local APIC has default address
510 	 */
511 	mp_lapic_addr = APIC_DEFAULT_PHYS_BASE;
512 
513 	/*
514 	 * 2 CPUs, numbered 0 & 1.
515 	 */
516 	processor.type = MP_PROCESSOR;
517 	/* Either an integrated APIC or a discrete 82489DX. */
518 	processor.apicver = mpc_default_type > 4 ? 0x10 : 0x01;
519 	processor.cpuflag = CPU_ENABLED;
520 	processor.cpufeature = (boot_cpu_data.x86 << 8) |
521 	    (boot_cpu_data.x86_model << 4) | boot_cpu_data.x86_mask;
522 	processor.featureflag = boot_cpu_data.x86_capability[0];
523 	processor.reserved[0] = 0;
524 	processor.reserved[1] = 0;
525 	for (i = 0; i < 2; i++) {
526 		processor.apicid = i;
527 		MP_processor_info(&processor);
528 	}
529 
530 	construct_ioapic_table(mpc_default_type);
531 
532 	lintsrc.type = MP_LINTSRC;
533 	lintsrc.irqflag = 0;		/* conforming */
534 	lintsrc.srcbusid = 0;
535 	lintsrc.srcbusirq = 0;
536 	lintsrc.destapic = MP_APIC_ALL;
537 	for (i = 0; i < 2; i++) {
538 		lintsrc.irqtype = linttypes[i];
539 		lintsrc.destapiclint = i;
540 		MP_lintsrc_info(&lintsrc);
541 	}
542 }
543 
544 static struct mpf_intel *mpf_found;
545 
546 static unsigned long __init get_mpc_size(unsigned long physptr)
547 {
548 	struct mpc_table *mpc;
549 	unsigned long size;
550 
551 	mpc = early_ioremap(physptr, PAGE_SIZE);
552 	size = mpc->length;
553 	early_iounmap(mpc, PAGE_SIZE);
554 	apic_printk(APIC_VERBOSE, "  mpc: %lx-%lx\n", physptr, physptr + size);
555 
556 	return size;
557 }
558 
559 static int __init check_physptr(struct mpf_intel *mpf, unsigned int early)
560 {
561 	struct mpc_table *mpc;
562 	unsigned long size;
563 
564 	size = get_mpc_size(mpf->physptr);
565 	mpc = early_ioremap(mpf->physptr, size);
566 	/*
567 	 * Read the physical hardware table.  Anything here will
568 	 * override the defaults.
569 	 */
570 	if (!smp_read_mpc(mpc, early)) {
571 #ifdef CONFIG_X86_LOCAL_APIC
572 		smp_found_config = 0;
573 #endif
574 		printk(KERN_ERR "BIOS bug, MP table errors detected!...\n"
575 			"... disabling SMP support. (tell your hw vendor)\n");
576 		early_iounmap(mpc, size);
577 		return -1;
578 	}
579 	early_iounmap(mpc, size);
580 
581 	if (early)
582 		return -1;
583 
584 #ifdef CONFIG_X86_IO_APIC
585 	/*
586 	 * If there are no explicit MP IRQ entries, then we are
587 	 * broken.  We set up most of the low 16 IO-APIC pins to
588 	 * ISA defaults and hope it will work.
589 	 */
590 	if (!mp_irq_entries) {
591 		struct mpc_bus bus;
592 
593 		printk(KERN_ERR "BIOS bug, no explicit IRQ entries, "
594 		       "using default mptable. (tell your hw vendor)\n");
595 
596 		bus.type = MP_BUS;
597 		bus.busid = 0;
598 		memcpy(bus.bustype, "ISA   ", 6);
599 		MP_bus_info(&bus);
600 
601 		construct_default_ioirq_mptable(0);
602 	}
603 #endif
604 
605 	return 0;
606 }
607 
608 /*
609  * Scan the memory blocks for an SMP configuration block.
610  */
611 static void __init __get_smp_config(unsigned int early)
612 {
613 	struct mpf_intel *mpf = mpf_found;
614 
615 	if (!mpf)
616 		return;
617 
618 	if (acpi_lapic && early)
619 		return;
620 
621 	/*
622 	 * MPS doesn't support hyperthreading, aka only have
623 	 * thread 0 apic id in MPS table
624 	 */
625 	if (acpi_lapic && acpi_ioapic)
626 		return;
627 
628 	if (x86_quirks->mach_get_smp_config) {
629 		if (x86_quirks->mach_get_smp_config(early))
630 			return;
631 	}
632 
633 	printk(KERN_INFO "Intel MultiProcessor Specification v1.%d\n",
634 	       mpf->specification);
635 #if defined(CONFIG_X86_LOCAL_APIC) && defined(CONFIG_X86_32)
636 	if (mpf->feature2 & (1 << 7)) {
637 		printk(KERN_INFO "    IMCR and PIC compatibility mode.\n");
638 		pic_mode = 1;
639 	} else {
640 		printk(KERN_INFO "    Virtual Wire compatibility mode.\n");
641 		pic_mode = 0;
642 	}
643 #endif
644 	/*
645 	 * Now see if we need to read further.
646 	 */
647 	if (mpf->feature1 != 0) {
648 		if (early) {
649 			/*
650 			 * local APIC has default address
651 			 */
652 			mp_lapic_addr = APIC_DEFAULT_PHYS_BASE;
653 			return;
654 		}
655 
656 		printk(KERN_INFO "Default MP configuration #%d\n",
657 		       mpf->feature1);
658 		construct_default_ISA_mptable(mpf->feature1);
659 
660 	} else if (mpf->physptr) {
661 		if (check_physptr(mpf, early))
662 			return;
663 	} else
664 		BUG();
665 
666 	if (!early)
667 		printk(KERN_INFO "Processors: %d\n", num_processors);
668 	/*
669 	 * Only use the first configuration found.
670 	 */
671 }
672 
673 void __init early_get_smp_config(void)
674 {
675 	__get_smp_config(1);
676 }
677 
678 void __init get_smp_config(void)
679 {
680 	__get_smp_config(0);
681 }
682 
683 static void __init smp_reserve_bootmem(struct mpf_intel *mpf)
684 {
685 	unsigned long size = get_mpc_size(mpf->physptr);
686 #ifdef CONFIG_X86_32
687 	/*
688 	 * We cannot access to MPC table to compute table size yet,
689 	 * as only few megabytes from the bottom is mapped now.
690 	 * PC-9800's MPC table places on the very last of physical
691 	 * memory; so that simply reserving PAGE_SIZE from mpf->physptr
692 	 * yields BUG() in reserve_bootmem.
693 	 * also need to make sure physptr is below than max_low_pfn
694 	 * we don't need reserve the area above max_low_pfn
695 	 */
696 	unsigned long end = max_low_pfn * PAGE_SIZE;
697 
698 	if (mpf->physptr < end) {
699 		if (mpf->physptr + size > end)
700 			size = end - mpf->physptr;
701 		reserve_bootmem_generic(mpf->physptr, size, BOOTMEM_DEFAULT);
702 	}
703 #else
704 	reserve_bootmem_generic(mpf->physptr, size, BOOTMEM_DEFAULT);
705 #endif
706 }
707 
708 static int __init smp_scan_config(unsigned long base, unsigned long length,
709 				  unsigned reserve)
710 {
711 	unsigned int *bp = phys_to_virt(base);
712 	struct mpf_intel *mpf;
713 
714 	apic_printk(APIC_VERBOSE, "Scan SMP from %p for %ld bytes.\n",
715 			bp, length);
716 	BUILD_BUG_ON(sizeof(*mpf) != 16);
717 
718 	while (length > 0) {
719 		mpf = (struct mpf_intel *)bp;
720 		if ((*bp == SMP_MAGIC_IDENT) &&
721 		    (mpf->length == 1) &&
722 		    !mpf_checksum((unsigned char *)bp, 16) &&
723 		    ((mpf->specification == 1)
724 		     || (mpf->specification == 4))) {
725 #ifdef CONFIG_X86_LOCAL_APIC
726 			smp_found_config = 1;
727 #endif
728 			mpf_found = mpf;
729 
730 			printk(KERN_INFO "found SMP MP-table at [%p] %llx\n",
731 			       mpf, (u64)virt_to_phys(mpf));
732 
733 			if (!reserve)
734 				return 1;
735 			reserve_bootmem_generic(virt_to_phys(mpf), sizeof(*mpf),
736 						BOOTMEM_DEFAULT);
737 			if (mpf->physptr)
738 				smp_reserve_bootmem(mpf);
739 
740 			return 1;
741 		}
742 		bp += 4;
743 		length -= 16;
744 	}
745 	return 0;
746 }
747 
748 static void __init __find_smp_config(unsigned int reserve)
749 {
750 	unsigned int address;
751 
752 	if (x86_quirks->mach_find_smp_config) {
753 		if (x86_quirks->mach_find_smp_config(reserve))
754 			return;
755 	}
756 	/*
757 	 * FIXME: Linux assumes you have 640K of base ram..
758 	 * this continues the error...
759 	 *
760 	 * 1) Scan the bottom 1K for a signature
761 	 * 2) Scan the top 1K of base RAM
762 	 * 3) Scan the 64K of bios
763 	 */
764 	if (smp_scan_config(0x0, 0x400, reserve) ||
765 	    smp_scan_config(639 * 0x400, 0x400, reserve) ||
766 	    smp_scan_config(0xF0000, 0x10000, reserve))
767 		return;
768 	/*
769 	 * If it is an SMP machine we should know now, unless the
770 	 * configuration is in an EISA/MCA bus machine with an
771 	 * extended bios data area.
772 	 *
773 	 * there is a real-mode segmented pointer pointing to the
774 	 * 4K EBDA area at 0x40E, calculate and scan it here.
775 	 *
776 	 * NOTE! There are Linux loaders that will corrupt the EBDA
777 	 * area, and as such this kind of SMP config may be less
778 	 * trustworthy, simply because the SMP table may have been
779 	 * stomped on during early boot. These loaders are buggy and
780 	 * should be fixed.
781 	 *
782 	 * MP1.4 SPEC states to only scan first 1K of 4K EBDA.
783 	 */
784 
785 	address = get_bios_ebda();
786 	if (address)
787 		smp_scan_config(address, 0x400, reserve);
788 }
789 
790 void __init early_find_smp_config(void)
791 {
792 	__find_smp_config(0);
793 }
794 
795 void __init find_smp_config(void)
796 {
797 	__find_smp_config(1);
798 }
799 
800 #ifdef CONFIG_X86_IO_APIC
801 static u8 __initdata irq_used[MAX_IRQ_SOURCES];
802 
803 static int  __init get_MP_intsrc_index(struct mpc_intsrc *m)
804 {
805 	int i;
806 
807 	if (m->irqtype != mp_INT)
808 		return 0;
809 
810 	if (m->irqflag != 0x0f)
811 		return 0;
812 
813 	/* not legacy */
814 
815 	for (i = 0; i < mp_irq_entries; i++) {
816 		if (mp_irqs[i].irqtype != mp_INT)
817 			continue;
818 
819 		if (mp_irqs[i].irqflag != 0x0f)
820 			continue;
821 
822 		if (mp_irqs[i].srcbus != m->srcbus)
823 			continue;
824 		if (mp_irqs[i].srcbusirq != m->srcbusirq)
825 			continue;
826 		if (irq_used[i]) {
827 			/* already claimed */
828 			return -2;
829 		}
830 		irq_used[i] = 1;
831 		return i;
832 	}
833 
834 	/* not found */
835 	return -1;
836 }
837 
838 #define SPARE_SLOT_NUM 20
839 
840 static struct mpc_intsrc __initdata *m_spare[SPARE_SLOT_NUM];
841 
842 static void __init check_irq_src(struct mpc_intsrc *m, int *nr_m_spare)
843 {
844 	int i;
845 
846 	apic_printk(APIC_VERBOSE, "OLD ");
847 	print_MP_intsrc_info(m);
848 
849 	i = get_MP_intsrc_index(m);
850 	if (i > 0) {
851 		assign_to_mpc_intsrc(&mp_irqs[i], m);
852 		apic_printk(APIC_VERBOSE, "NEW ");
853 		print_mp_irq_info(&mp_irqs[i]);
854 		return;
855 	}
856 	if (!i) {
857 		/* legacy, do nothing */
858 		return;
859 	}
860 	if (*nr_m_spare < SPARE_SLOT_NUM) {
861 		/*
862 		 * not found (-1), or duplicated (-2) are invalid entries,
863 		 * we need to use the slot later
864 		 */
865 		m_spare[*nr_m_spare] = m;
866 		*nr_m_spare += 1;
867 	}
868 }
869 #else /* CONFIG_X86_IO_APIC */
870 static
871 inline void __init check_irq_src(struct mpc_intsrc *m, int *nr_m_spare) {}
872 #endif /* CONFIG_X86_IO_APIC */
873 
874 static int
875 check_slot(unsigned long mpc_new_phys, unsigned long mpc_new_length, int count)
876 {
877 	int ret = 0;
878 
879 	if (!mpc_new_phys || count <= mpc_new_length) {
880 		WARN(1, "update_mptable: No spare slots (length: %x)\n", count);
881 		return -1;
882 	}
883 
884 	return ret;
885 }
886 
887 static int  __init replace_intsrc_all(struct mpc_table *mpc,
888 					unsigned long mpc_new_phys,
889 					unsigned long mpc_new_length)
890 {
891 #ifdef CONFIG_X86_IO_APIC
892 	int i;
893 #endif
894 	int count = sizeof(*mpc);
895 	int nr_m_spare = 0;
896 	unsigned char *mpt = ((unsigned char *)mpc) + count;
897 
898 	printk(KERN_INFO "mpc_length %x\n", mpc->length);
899 	while (count < mpc->length) {
900 		switch (*mpt) {
901 		case MP_PROCESSOR:
902 			skip_entry(&mpt, &count, sizeof(struct mpc_cpu));
903 			break;
904 		case MP_BUS:
905 			skip_entry(&mpt, &count, sizeof(struct mpc_bus));
906 			break;
907 		case MP_IOAPIC:
908 			skip_entry(&mpt, &count, sizeof(struct mpc_ioapic));
909 			break;
910 		case MP_INTSRC:
911 			check_irq_src((struct mpc_intsrc *)mpt, &nr_m_spare);
912 			skip_entry(&mpt, &count, sizeof(struct mpc_intsrc));
913 			break;
914 		case MP_LINTSRC:
915 			skip_entry(&mpt, &count, sizeof(struct mpc_lintsrc));
916 			break;
917 		default:
918 			/* wrong mptable */
919 			smp_dump_mptable(mpc, mpt);
920 			goto out;
921 		}
922 	}
923 
924 #ifdef CONFIG_X86_IO_APIC
925 	for (i = 0; i < mp_irq_entries; i++) {
926 		if (irq_used[i])
927 			continue;
928 
929 		if (mp_irqs[i].irqtype != mp_INT)
930 			continue;
931 
932 		if (mp_irqs[i].irqflag != 0x0f)
933 			continue;
934 
935 		if (nr_m_spare > 0) {
936 			apic_printk(APIC_VERBOSE, "*NEW* found\n");
937 			nr_m_spare--;
938 			assign_to_mpc_intsrc(&mp_irqs[i], m_spare[nr_m_spare]);
939 			m_spare[nr_m_spare] = NULL;
940 		} else {
941 			struct mpc_intsrc *m = (struct mpc_intsrc *)mpt;
942 			count += sizeof(struct mpc_intsrc);
943 			if (check_slot(mpc_new_phys, mpc_new_length, count) < 0)
944 				goto out;
945 			assign_to_mpc_intsrc(&mp_irqs[i], m);
946 			mpc->length = count;
947 			mpt += sizeof(struct mpc_intsrc);
948 		}
949 		print_mp_irq_info(&mp_irqs[i]);
950 	}
951 #endif
952 out:
953 	/* update checksum */
954 	mpc->checksum = 0;
955 	mpc->checksum -= mpf_checksum((unsigned char *)mpc, mpc->length);
956 
957 	return 0;
958 }
959 
960 int enable_update_mptable;
961 
962 static int __init update_mptable_setup(char *str)
963 {
964 	enable_update_mptable = 1;
965 #ifdef CONFIG_PCI
966 	pci_routeirq = 1;
967 #endif
968 	return 0;
969 }
970 early_param("update_mptable", update_mptable_setup);
971 
972 static unsigned long __initdata mpc_new_phys;
973 static unsigned long mpc_new_length __initdata = 4096;
974 
975 /* alloc_mptable or alloc_mptable=4k */
976 static int __initdata alloc_mptable;
977 static int __init parse_alloc_mptable_opt(char *p)
978 {
979 	enable_update_mptable = 1;
980 #ifdef CONFIG_PCI
981 	pci_routeirq = 1;
982 #endif
983 	alloc_mptable = 1;
984 	if (!p)
985 		return 0;
986 	mpc_new_length = memparse(p, &p);
987 	return 0;
988 }
989 early_param("alloc_mptable", parse_alloc_mptable_opt);
990 
991 void __init early_reserve_e820_mpc_new(void)
992 {
993 	if (enable_update_mptable && alloc_mptable) {
994 		u64 startt = 0;
995 #ifdef CONFIG_X86_TRAMPOLINE
996 		startt = TRAMPOLINE_BASE;
997 #endif
998 		mpc_new_phys = early_reserve_e820(startt, mpc_new_length, 4);
999 	}
1000 }
1001 
1002 static int __init update_mp_table(void)
1003 {
1004 	char str[16];
1005 	char oem[10];
1006 	struct mpf_intel *mpf;
1007 	struct mpc_table *mpc, *mpc_new;
1008 
1009 	if (!enable_update_mptable)
1010 		return 0;
1011 
1012 	mpf = mpf_found;
1013 	if (!mpf)
1014 		return 0;
1015 
1016 	/*
1017 	 * Now see if we need to go further.
1018 	 */
1019 	if (mpf->feature1 != 0)
1020 		return 0;
1021 
1022 	if (!mpf->physptr)
1023 		return 0;
1024 
1025 	mpc = phys_to_virt(mpf->physptr);
1026 
1027 	if (!smp_check_mpc(mpc, oem, str))
1028 		return 0;
1029 
1030 	printk(KERN_INFO "mpf: %llx\n", (u64)virt_to_phys(mpf));
1031 	printk(KERN_INFO "physptr: %x\n", mpf->physptr);
1032 
1033 	if (mpc_new_phys && mpc->length > mpc_new_length) {
1034 		mpc_new_phys = 0;
1035 		printk(KERN_INFO "mpc_new_length is %ld, please use alloc_mptable=8k\n",
1036 			 mpc_new_length);
1037 	}
1038 
1039 	if (!mpc_new_phys) {
1040 		unsigned char old, new;
1041 		/* check if we can change the postion */
1042 		mpc->checksum = 0;
1043 		old = mpf_checksum((unsigned char *)mpc, mpc->length);
1044 		mpc->checksum = 0xff;
1045 		new = mpf_checksum((unsigned char *)mpc, mpc->length);
1046 		if (old == new) {
1047 			printk(KERN_INFO "mpc is readonly, please try alloc_mptable instead\n");
1048 			return 0;
1049 		}
1050 		printk(KERN_INFO "use in-positon replacing\n");
1051 	} else {
1052 		mpf->physptr = mpc_new_phys;
1053 		mpc_new = phys_to_virt(mpc_new_phys);
1054 		memcpy(mpc_new, mpc, mpc->length);
1055 		mpc = mpc_new;
1056 		/* check if we can modify that */
1057 		if (mpc_new_phys - mpf->physptr) {
1058 			struct mpf_intel *mpf_new;
1059 			/* steal 16 bytes from [0, 1k) */
1060 			printk(KERN_INFO "mpf new: %x\n", 0x400 - 16);
1061 			mpf_new = phys_to_virt(0x400 - 16);
1062 			memcpy(mpf_new, mpf, 16);
1063 			mpf = mpf_new;
1064 			mpf->physptr = mpc_new_phys;
1065 		}
1066 		mpf->checksum = 0;
1067 		mpf->checksum -= mpf_checksum((unsigned char *)mpf, 16);
1068 		printk(KERN_INFO "physptr new: %x\n", mpf->physptr);
1069 	}
1070 
1071 	/*
1072 	 * only replace the one with mp_INT and
1073 	 *	 MP_IRQ_TRIGGER_LEVEL|MP_IRQ_POLARITY_LOW,
1074 	 * already in mp_irqs , stored by ... and mp_config_acpi_gsi,
1075 	 * may need pci=routeirq for all coverage
1076 	 */
1077 	replace_intsrc_all(mpc, mpc_new_phys, mpc_new_length);
1078 
1079 	return 0;
1080 }
1081 
1082 late_initcall(update_mp_table);
1083