xref: /openbmc/linux/arch/x86/kernel/mpparse.c (revision b627b4ed)
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 
21 #include <asm/mtrr.h>
22 #include <asm/mpspec.h>
23 #include <asm/pgalloc.h>
24 #include <asm/io_apic.h>
25 #include <asm/proto.h>
26 #include <asm/bios_ebda.h>
27 #include <asm/e820.h>
28 #include <asm/trampoline.h>
29 #include <asm/setup.h>
30 #include <asm/smp.h>
31 
32 #include <asm/apic.h>
33 /*
34  * Checksum an MP configuration block.
35  */
36 
37 static int __init mpf_checksum(unsigned char *mp, int len)
38 {
39 	int sum = 0;
40 
41 	while (len--)
42 		sum += *mp++;
43 
44 	return sum & 0xFF;
45 }
46 
47 static void __init MP_processor_info(struct mpc_cpu *m)
48 {
49 	int apicid;
50 	char *bootup_cpu = "";
51 
52 	if (!(m->cpuflag & CPU_ENABLED)) {
53 		disabled_cpus++;
54 		return;
55 	}
56 
57 	if (x86_quirks->mpc_apic_id)
58 		apicid = x86_quirks->mpc_apic_id(m);
59 	else
60 		apicid = m->apicid;
61 
62 	if (m->cpuflag & CPU_BOOTPROCESSOR) {
63 		bootup_cpu = " (Bootup-CPU)";
64 		boot_cpu_physical_apicid = m->apicid;
65 	}
66 
67 	printk(KERN_INFO "Processor #%d%s\n", m->apicid, bootup_cpu);
68 	generic_processor_info(apicid, m->apicver);
69 }
70 
71 #ifdef CONFIG_X86_IO_APIC
72 static void __init MP_bus_info(struct mpc_bus *m)
73 {
74 	char str[7];
75 	memcpy(str, m->bustype, 6);
76 	str[6] = 0;
77 
78 	if (x86_quirks->mpc_oem_bus_info)
79 		x86_quirks->mpc_oem_bus_info(m, str);
80 	else
81 		apic_printk(APIC_VERBOSE, "Bus #%d is %s\n", m->busid, str);
82 
83 #if MAX_MP_BUSSES < 256
84 	if (m->busid >= MAX_MP_BUSSES) {
85 		printk(KERN_WARNING "MP table busid value (%d) for bustype %s "
86 		       " is too large, max. supported is %d\n",
87 		       m->busid, str, MAX_MP_BUSSES - 1);
88 		return;
89 	}
90 #endif
91 
92 	if (strncmp(str, BUSTYPE_ISA, sizeof(BUSTYPE_ISA) - 1) == 0) {
93 		set_bit(m->busid, mp_bus_not_pci);
94 #if defined(CONFIG_EISA) || defined(CONFIG_MCA)
95 		mp_bus_id_to_type[m->busid] = MP_BUS_ISA;
96 #endif
97 	} else if (strncmp(str, BUSTYPE_PCI, sizeof(BUSTYPE_PCI) - 1) == 0) {
98 		if (x86_quirks->mpc_oem_pci_bus)
99 			x86_quirks->mpc_oem_pci_bus(m);
100 
101 		clear_bit(m->busid, mp_bus_not_pci);
102 #if defined(CONFIG_EISA) || defined(CONFIG_MCA)
103 		mp_bus_id_to_type[m->busid] = MP_BUS_PCI;
104 	} else if (strncmp(str, BUSTYPE_EISA, sizeof(BUSTYPE_EISA) - 1) == 0) {
105 		mp_bus_id_to_type[m->busid] = MP_BUS_EISA;
106 	} else if (strncmp(str, BUSTYPE_MCA, sizeof(BUSTYPE_MCA) - 1) == 0) {
107 		mp_bus_id_to_type[m->busid] = MP_BUS_MCA;
108 #endif
109 	} else
110 		printk(KERN_WARNING "Unknown bustype %s - ignoring\n", str);
111 }
112 
113 static int bad_ioapic(unsigned long address)
114 {
115 	if (nr_ioapics >= MAX_IO_APICS) {
116 		printk(KERN_ERR "ERROR: Max # of I/O APICs (%d) exceeded "
117 		       "(found %d)\n", MAX_IO_APICS, nr_ioapics);
118 		panic("Recompile kernel with bigger MAX_IO_APICS!\n");
119 	}
120 	if (!address) {
121 		printk(KERN_ERR "WARNING: Bogus (zero) I/O APIC address"
122 		       " found in table, skipping!\n");
123 		return 1;
124 	}
125 	return 0;
126 }
127 
128 static void __init MP_ioapic_info(struct mpc_ioapic *m)
129 {
130 	if (!(m->flags & MPC_APIC_USABLE))
131 		return;
132 
133 	printk(KERN_INFO "I/O APIC #%d Version %d at 0x%X.\n",
134 	       m->apicid, m->apicver, m->apicaddr);
135 
136 	if (bad_ioapic(m->apicaddr))
137 		return;
138 
139 	mp_ioapics[nr_ioapics].apicaddr = m->apicaddr;
140 	mp_ioapics[nr_ioapics].apicid = m->apicid;
141 	mp_ioapics[nr_ioapics].type = m->type;
142 	mp_ioapics[nr_ioapics].apicver = m->apicver;
143 	mp_ioapics[nr_ioapics].flags = m->flags;
144 	nr_ioapics++;
145 }
146 
147 static void print_MP_intsrc_info(struct mpc_intsrc *m)
148 {
149 	apic_printk(APIC_VERBOSE, "Int: type %d, pol %d, trig %d, bus %02x,"
150 		" IRQ %02x, APIC ID %x, APIC INT %02x\n",
151 		m->irqtype, m->irqflag & 3, (m->irqflag >> 2) & 3, m->srcbus,
152 		m->srcbusirq, m->dstapic, m->dstirq);
153 }
154 
155 static void __init print_mp_irq_info(struct mpc_intsrc *mp_irq)
156 {
157 	apic_printk(APIC_VERBOSE, "Int: type %d, pol %d, trig %d, bus %02x,"
158 		" IRQ %02x, APIC ID %x, APIC INT %02x\n",
159 		mp_irq->irqtype, mp_irq->irqflag & 3,
160 		(mp_irq->irqflag >> 2) & 3, mp_irq->srcbus,
161 		mp_irq->srcbusirq, mp_irq->dstapic, mp_irq->dstirq);
162 }
163 
164 static void __init assign_to_mp_irq(struct mpc_intsrc *m,
165 				    struct mpc_intsrc *mp_irq)
166 {
167 	mp_irq->dstapic = m->dstapic;
168 	mp_irq->type = m->type;
169 	mp_irq->irqtype = m->irqtype;
170 	mp_irq->irqflag = m->irqflag;
171 	mp_irq->srcbus = m->srcbus;
172 	mp_irq->srcbusirq = m->srcbusirq;
173 	mp_irq->dstirq = m->dstirq;
174 }
175 
176 static void __init assign_to_mpc_intsrc(struct mpc_intsrc *mp_irq,
177 					struct mpc_intsrc *m)
178 {
179 	m->dstapic = mp_irq->dstapic;
180 	m->type = mp_irq->type;
181 	m->irqtype = mp_irq->irqtype;
182 	m->irqflag = mp_irq->irqflag;
183 	m->srcbus = mp_irq->srcbus;
184 	m->srcbusirq = mp_irq->srcbusirq;
185 	m->dstirq = mp_irq->dstirq;
186 }
187 
188 static int __init mp_irq_mpc_intsrc_cmp(struct mpc_intsrc *mp_irq,
189 					struct mpc_intsrc *m)
190 {
191 	if (mp_irq->dstapic != m->dstapic)
192 		return 1;
193 	if (mp_irq->type != m->type)
194 		return 2;
195 	if (mp_irq->irqtype != m->irqtype)
196 		return 3;
197 	if (mp_irq->irqflag != m->irqflag)
198 		return 4;
199 	if (mp_irq->srcbus != m->srcbus)
200 		return 5;
201 	if (mp_irq->srcbusirq != m->srcbusirq)
202 		return 6;
203 	if (mp_irq->dstirq != m->dstirq)
204 		return 7;
205 
206 	return 0;
207 }
208 
209 static void __init MP_intsrc_info(struct mpc_intsrc *m)
210 {
211 	int i;
212 
213 	print_MP_intsrc_info(m);
214 
215 	for (i = 0; i < mp_irq_entries; i++) {
216 		if (!mp_irq_mpc_intsrc_cmp(&mp_irqs[i], m))
217 			return;
218 	}
219 
220 	assign_to_mp_irq(m, &mp_irqs[mp_irq_entries]);
221 	if (++mp_irq_entries == MAX_IRQ_SOURCES)
222 		panic("Max # of irq sources exceeded!!\n");
223 }
224 #else /* CONFIG_X86_IO_APIC */
225 static inline void __init MP_bus_info(struct mpc_bus *m) {}
226 static inline void __init MP_ioapic_info(struct mpc_ioapic *m) {}
227 static inline void __init MP_intsrc_info(struct mpc_intsrc *m) {}
228 #endif /* CONFIG_X86_IO_APIC */
229 
230 
231 static void __init MP_lintsrc_info(struct mpc_lintsrc *m)
232 {
233 	apic_printk(APIC_VERBOSE, "Lint: type %d, pol %d, trig %d, bus %02x,"
234 		" IRQ %02x, APIC ID %x, APIC LINT %02x\n",
235 		m->irqtype, m->irqflag & 3, (m->irqflag >> 2) & 3, m->srcbusid,
236 		m->srcbusirq, m->destapic, m->destapiclint);
237 }
238 
239 /*
240  * Read/parse the MPC
241  */
242 
243 static int __init smp_check_mpc(struct mpc_table *mpc, char *oem, char *str)
244 {
245 
246 	if (memcmp(mpc->signature, MPC_SIGNATURE, 4)) {
247 		printk(KERN_ERR "MPTABLE: bad signature [%c%c%c%c]!\n",
248 		       mpc->signature[0], mpc->signature[1],
249 		       mpc->signature[2], mpc->signature[3]);
250 		return 0;
251 	}
252 	if (mpf_checksum((unsigned char *)mpc, mpc->length)) {
253 		printk(KERN_ERR "MPTABLE: checksum error!\n");
254 		return 0;
255 	}
256 	if (mpc->spec != 0x01 && mpc->spec != 0x04) {
257 		printk(KERN_ERR "MPTABLE: bad table version (%d)!!\n",
258 		       mpc->spec);
259 		return 0;
260 	}
261 	if (!mpc->lapic) {
262 		printk(KERN_ERR "MPTABLE: null local APIC address!\n");
263 		return 0;
264 	}
265 	memcpy(oem, mpc->oem, 8);
266 	oem[8] = 0;
267 	printk(KERN_INFO "MPTABLE: OEM ID: %s\n", oem);
268 
269 	memcpy(str, mpc->productid, 12);
270 	str[12] = 0;
271 
272 	printk(KERN_INFO "MPTABLE: Product ID: %s\n", str);
273 
274 	printk(KERN_INFO "MPTABLE: APIC at: 0x%X\n", mpc->lapic);
275 
276 	return 1;
277 }
278 
279 static void skip_entry(unsigned char **ptr, int *count, int size)
280 {
281 	*ptr += size;
282 	*count += size;
283 }
284 
285 static void __init smp_dump_mptable(struct mpc_table *mpc, unsigned char *mpt)
286 {
287 	printk(KERN_ERR "Your mptable is wrong, contact your HW vendor!\n"
288 		"type %x\n", *mpt);
289 	print_hex_dump(KERN_ERR, "  ", DUMP_PREFIX_ADDRESS, 16,
290 			1, mpc, mpc->length, 1);
291 }
292 
293 static int __init smp_read_mpc(struct mpc_table *mpc, unsigned early)
294 {
295 	char str[16];
296 	char oem[10];
297 
298 	int count = sizeof(*mpc);
299 	unsigned char *mpt = ((unsigned char *)mpc) + count;
300 
301 	if (!smp_check_mpc(mpc, oem, str))
302 		return 0;
303 
304 #ifdef CONFIG_X86_32
305 	generic_mps_oem_check(mpc, oem, str);
306 #endif
307 	/* save the local APIC address, it might be non-default */
308 	if (!acpi_lapic)
309 		mp_lapic_addr = mpc->lapic;
310 
311 	if (early)
312 		return 1;
313 
314 	if (mpc->oemptr && x86_quirks->smp_read_mpc_oem) {
315 		struct mpc_oemtable *oem_table = (void *)(long)mpc->oemptr;
316 		x86_quirks->smp_read_mpc_oem(oem_table, mpc->oemsize);
317 	}
318 
319 	/*
320 	 *      Now process the configuration blocks.
321 	 */
322 	if (x86_quirks->mpc_record)
323 		*x86_quirks->mpc_record = 0;
324 
325 	while (count < mpc->length) {
326 		switch (*mpt) {
327 		case MP_PROCESSOR:
328 			/* ACPI may have already provided this data */
329 			if (!acpi_lapic)
330 				MP_processor_info((struct mpc_cpu *)mpt);
331 			skip_entry(&mpt, &count, sizeof(struct mpc_cpu));
332 			break;
333 		case MP_BUS:
334 			MP_bus_info((struct mpc_bus *)mpt);
335 			skip_entry(&mpt, &count, sizeof(struct mpc_bus));
336 			break;
337 		case MP_IOAPIC:
338 			MP_ioapic_info((struct mpc_ioapic *)mpt);
339 			skip_entry(&mpt, &count, sizeof(struct mpc_ioapic));
340 			break;
341 		case MP_INTSRC:
342 			MP_intsrc_info((struct mpc_intsrc *)mpt);
343 			skip_entry(&mpt, &count, sizeof(struct mpc_intsrc));
344 			break;
345 		case MP_LINTSRC:
346 			MP_lintsrc_info((struct mpc_lintsrc *)mpt);
347 			skip_entry(&mpt, &count, sizeof(struct mpc_lintsrc));
348 			break;
349 		default:
350 			/* wrong mptable */
351 			smp_dump_mptable(mpc, mpt);
352 			count = mpc->length;
353 			break;
354 		}
355 		if (x86_quirks->mpc_record)
356 			(*x86_quirks->mpc_record)++;
357 	}
358 
359 #ifdef CONFIG_X86_BIGSMP
360 	generic_bigsmp_probe();
361 #endif
362 
363 	if (apic->setup_apic_routing)
364 		apic->setup_apic_routing();
365 
366 	if (!num_processors)
367 		printk(KERN_ERR "MPTABLE: no processors registered!\n");
368 	return num_processors;
369 }
370 
371 #ifdef CONFIG_X86_IO_APIC
372 
373 static int __init ELCR_trigger(unsigned int irq)
374 {
375 	unsigned int port;
376 
377 	port = 0x4d0 + (irq >> 3);
378 	return (inb(port) >> (irq & 7)) & 1;
379 }
380 
381 static void __init construct_default_ioirq_mptable(int mpc_default_type)
382 {
383 	struct mpc_intsrc intsrc;
384 	int i;
385 	int ELCR_fallback = 0;
386 
387 	intsrc.type = MP_INTSRC;
388 	intsrc.irqflag = 0;	/* conforming */
389 	intsrc.srcbus = 0;
390 	intsrc.dstapic = mp_ioapics[0].apicid;
391 
392 	intsrc.irqtype = mp_INT;
393 
394 	/*
395 	 *  If true, we have an ISA/PCI system with no IRQ entries
396 	 *  in the MP table. To prevent the PCI interrupts from being set up
397 	 *  incorrectly, we try to use the ELCR. The sanity check to see if
398 	 *  there is good ELCR data is very simple - IRQ0, 1, 2 and 13 can
399 	 *  never be level sensitive, so we simply see if the ELCR agrees.
400 	 *  If it does, we assume it's valid.
401 	 */
402 	if (mpc_default_type == 5) {
403 		printk(KERN_INFO "ISA/PCI bus type with no IRQ information... "
404 		       "falling back to ELCR\n");
405 
406 		if (ELCR_trigger(0) || ELCR_trigger(1) || ELCR_trigger(2) ||
407 		    ELCR_trigger(13))
408 			printk(KERN_ERR "ELCR contains invalid data... "
409 			       "not using ELCR\n");
410 		else {
411 			printk(KERN_INFO
412 			       "Using ELCR to identify PCI interrupts\n");
413 			ELCR_fallback = 1;
414 		}
415 	}
416 
417 	for (i = 0; i < 16; i++) {
418 		switch (mpc_default_type) {
419 		case 2:
420 			if (i == 0 || i == 13)
421 				continue;	/* IRQ0 & IRQ13 not connected */
422 			/* fall through */
423 		default:
424 			if (i == 2)
425 				continue;	/* IRQ2 is never connected */
426 		}
427 
428 		if (ELCR_fallback) {
429 			/*
430 			 *  If the ELCR indicates a level-sensitive interrupt, we
431 			 *  copy that information over to the MP table in the
432 			 *  irqflag field (level sensitive, active high polarity).
433 			 */
434 			if (ELCR_trigger(i))
435 				intsrc.irqflag = 13;
436 			else
437 				intsrc.irqflag = 0;
438 		}
439 
440 		intsrc.srcbusirq = i;
441 		intsrc.dstirq = i ? i : 2;	/* IRQ0 to INTIN2 */
442 		MP_intsrc_info(&intsrc);
443 	}
444 
445 	intsrc.irqtype = mp_ExtINT;
446 	intsrc.srcbusirq = 0;
447 	intsrc.dstirq = 0;	/* 8259A to INTIN0 */
448 	MP_intsrc_info(&intsrc);
449 }
450 
451 
452 static void __init construct_ioapic_table(int mpc_default_type)
453 {
454 	struct mpc_ioapic ioapic;
455 	struct mpc_bus bus;
456 
457 	bus.type = MP_BUS;
458 	bus.busid = 0;
459 	switch (mpc_default_type) {
460 	default:
461 		printk(KERN_ERR "???\nUnknown standard configuration %d\n",
462 		       mpc_default_type);
463 		/* fall through */
464 	case 1:
465 	case 5:
466 		memcpy(bus.bustype, "ISA   ", 6);
467 		break;
468 	case 2:
469 	case 6:
470 	case 3:
471 		memcpy(bus.bustype, "EISA  ", 6);
472 		break;
473 	case 4:
474 	case 7:
475 		memcpy(bus.bustype, "MCA   ", 6);
476 	}
477 	MP_bus_info(&bus);
478 	if (mpc_default_type > 4) {
479 		bus.busid = 1;
480 		memcpy(bus.bustype, "PCI   ", 6);
481 		MP_bus_info(&bus);
482 	}
483 
484 	ioapic.type = MP_IOAPIC;
485 	ioapic.apicid = 2;
486 	ioapic.apicver = mpc_default_type > 4 ? 0x10 : 0x01;
487 	ioapic.flags = MPC_APIC_USABLE;
488 	ioapic.apicaddr = 0xFEC00000;
489 	MP_ioapic_info(&ioapic);
490 
491 	/*
492 	 * We set up most of the low 16 IO-APIC pins according to MPS rules.
493 	 */
494 	construct_default_ioirq_mptable(mpc_default_type);
495 }
496 #else
497 static inline void __init construct_ioapic_table(int mpc_default_type) { }
498 #endif
499 
500 static inline void __init construct_default_ISA_mptable(int mpc_default_type)
501 {
502 	struct mpc_cpu processor;
503 	struct mpc_lintsrc lintsrc;
504 	int linttypes[2] = { mp_ExtINT, mp_NMI };
505 	int i;
506 
507 	/*
508 	 * local APIC has default address
509 	 */
510 	mp_lapic_addr = APIC_DEFAULT_PHYS_BASE;
511 
512 	/*
513 	 * 2 CPUs, numbered 0 & 1.
514 	 */
515 	processor.type = MP_PROCESSOR;
516 	/* Either an integrated APIC or a discrete 82489DX. */
517 	processor.apicver = mpc_default_type > 4 ? 0x10 : 0x01;
518 	processor.cpuflag = CPU_ENABLED;
519 	processor.cpufeature = (boot_cpu_data.x86 << 8) |
520 	    (boot_cpu_data.x86_model << 4) | boot_cpu_data.x86_mask;
521 	processor.featureflag = boot_cpu_data.x86_capability[0];
522 	processor.reserved[0] = 0;
523 	processor.reserved[1] = 0;
524 	for (i = 0; i < 2; i++) {
525 		processor.apicid = i;
526 		MP_processor_info(&processor);
527 	}
528 
529 	construct_ioapic_table(mpc_default_type);
530 
531 	lintsrc.type = MP_LINTSRC;
532 	lintsrc.irqflag = 0;		/* conforming */
533 	lintsrc.srcbusid = 0;
534 	lintsrc.srcbusirq = 0;
535 	lintsrc.destapic = MP_APIC_ALL;
536 	for (i = 0; i < 2; i++) {
537 		lintsrc.irqtype = linttypes[i];
538 		lintsrc.destapiclint = i;
539 		MP_lintsrc_info(&lintsrc);
540 	}
541 }
542 
543 static struct mpf_intel *mpf_found;
544 
545 static unsigned long __init get_mpc_size(unsigned long physptr)
546 {
547 	struct mpc_table *mpc;
548 	unsigned long size;
549 
550 	mpc = early_ioremap(physptr, PAGE_SIZE);
551 	size = mpc->length;
552 	early_iounmap(mpc, PAGE_SIZE);
553 	apic_printk(APIC_VERBOSE, "  mpc: %lx-%lx\n", physptr, physptr + size);
554 
555 	return size;
556 }
557 
558 static int __init check_physptr(struct mpf_intel *mpf, unsigned int early)
559 {
560 	struct mpc_table *mpc;
561 	unsigned long size;
562 
563 	size = get_mpc_size(mpf->physptr);
564 	mpc = early_ioremap(mpf->physptr, size);
565 	/*
566 	 * Read the physical hardware table.  Anything here will
567 	 * override the defaults.
568 	 */
569 	if (!smp_read_mpc(mpc, early)) {
570 #ifdef CONFIG_X86_LOCAL_APIC
571 		smp_found_config = 0;
572 #endif
573 		printk(KERN_ERR "BIOS bug, MP table errors detected!...\n"
574 			"... disabling SMP support. (tell your hw vendor)\n");
575 		early_iounmap(mpc, size);
576 		return -1;
577 	}
578 	early_iounmap(mpc, size);
579 
580 	if (early)
581 		return -1;
582 
583 #ifdef CONFIG_X86_IO_APIC
584 	/*
585 	 * If there are no explicit MP IRQ entries, then we are
586 	 * broken.  We set up most of the low 16 IO-APIC pins to
587 	 * ISA defaults and hope it will work.
588 	 */
589 	if (!mp_irq_entries) {
590 		struct mpc_bus bus;
591 
592 		printk(KERN_ERR "BIOS bug, no explicit IRQ entries, "
593 		       "using default mptable. (tell your hw vendor)\n");
594 
595 		bus.type = MP_BUS;
596 		bus.busid = 0;
597 		memcpy(bus.bustype, "ISA   ", 6);
598 		MP_bus_info(&bus);
599 
600 		construct_default_ioirq_mptable(0);
601 	}
602 #endif
603 
604 	return 0;
605 }
606 
607 /*
608  * Scan the memory blocks for an SMP configuration block.
609  */
610 static void __init __get_smp_config(unsigned int early)
611 {
612 	struct mpf_intel *mpf = mpf_found;
613 
614 	if (!mpf)
615 		return;
616 
617 	if (acpi_lapic && early)
618 		return;
619 
620 	/*
621 	 * MPS doesn't support hyperthreading, aka only have
622 	 * thread 0 apic id in MPS table
623 	 */
624 	if (acpi_lapic && acpi_ioapic)
625 		return;
626 
627 	if (x86_quirks->mach_get_smp_config) {
628 		if (x86_quirks->mach_get_smp_config(early))
629 			return;
630 	}
631 
632 	printk(KERN_INFO "Intel MultiProcessor Specification v1.%d\n",
633 	       mpf->specification);
634 #if defined(CONFIG_X86_LOCAL_APIC) && defined(CONFIG_X86_32)
635 	if (mpf->feature2 & (1 << 7)) {
636 		printk(KERN_INFO "    IMCR and PIC compatibility mode.\n");
637 		pic_mode = 1;
638 	} else {
639 		printk(KERN_INFO "    Virtual Wire compatibility mode.\n");
640 		pic_mode = 0;
641 	}
642 #endif
643 	/*
644 	 * Now see if we need to read further.
645 	 */
646 	if (mpf->feature1 != 0) {
647 		if (early) {
648 			/*
649 			 * local APIC has default address
650 			 */
651 			mp_lapic_addr = APIC_DEFAULT_PHYS_BASE;
652 			return;
653 		}
654 
655 		printk(KERN_INFO "Default MP configuration #%d\n",
656 		       mpf->feature1);
657 		construct_default_ISA_mptable(mpf->feature1);
658 
659 	} else if (mpf->physptr) {
660 		if (check_physptr(mpf, early))
661 			return;
662 	} else
663 		BUG();
664 
665 	if (!early)
666 		printk(KERN_INFO "Processors: %d\n", num_processors);
667 	/*
668 	 * Only use the first configuration found.
669 	 */
670 }
671 
672 void __init early_get_smp_config(void)
673 {
674 	__get_smp_config(1);
675 }
676 
677 void __init get_smp_config(void)
678 {
679 	__get_smp_config(0);
680 }
681 
682 static void __init smp_reserve_bootmem(struct mpf_intel *mpf)
683 {
684 	unsigned long size = get_mpc_size(mpf->physptr);
685 #ifdef CONFIG_X86_32
686 	/*
687 	 * We cannot access to MPC table to compute table size yet,
688 	 * as only few megabytes from the bottom is mapped now.
689 	 * PC-9800's MPC table places on the very last of physical
690 	 * memory; so that simply reserving PAGE_SIZE from mpf->physptr
691 	 * yields BUG() in reserve_bootmem.
692 	 * also need to make sure physptr is below than max_low_pfn
693 	 * we don't need reserve the area above max_low_pfn
694 	 */
695 	unsigned long end = max_low_pfn * PAGE_SIZE;
696 
697 	if (mpf->physptr < end) {
698 		if (mpf->physptr + size > end)
699 			size = end - mpf->physptr;
700 		reserve_bootmem_generic(mpf->physptr, size, BOOTMEM_DEFAULT);
701 	}
702 #else
703 	reserve_bootmem_generic(mpf->physptr, size, BOOTMEM_DEFAULT);
704 #endif
705 }
706 
707 static int __init smp_scan_config(unsigned long base, unsigned long length,
708 				  unsigned reserve)
709 {
710 	unsigned int *bp = phys_to_virt(base);
711 	struct mpf_intel *mpf;
712 
713 	apic_printk(APIC_VERBOSE, "Scan SMP from %p for %ld bytes.\n",
714 			bp, length);
715 	BUILD_BUG_ON(sizeof(*mpf) != 16);
716 
717 	while (length > 0) {
718 		mpf = (struct mpf_intel *)bp;
719 		if ((*bp == SMP_MAGIC_IDENT) &&
720 		    (mpf->length == 1) &&
721 		    !mpf_checksum((unsigned char *)bp, 16) &&
722 		    ((mpf->specification == 1)
723 		     || (mpf->specification == 4))) {
724 #ifdef CONFIG_X86_LOCAL_APIC
725 			smp_found_config = 1;
726 #endif
727 			mpf_found = mpf;
728 
729 			printk(KERN_INFO "found SMP MP-table at [%p] %llx\n",
730 			       mpf, (u64)virt_to_phys(mpf));
731 
732 			if (!reserve)
733 				return 1;
734 			reserve_bootmem_generic(virt_to_phys(mpf), sizeof(*mpf),
735 						BOOTMEM_DEFAULT);
736 			if (mpf->physptr)
737 				smp_reserve_bootmem(mpf);
738 
739 			return 1;
740 		}
741 		bp += 4;
742 		length -= 16;
743 	}
744 	return 0;
745 }
746 
747 static void __init __find_smp_config(unsigned int reserve)
748 {
749 	unsigned int address;
750 
751 	if (x86_quirks->mach_find_smp_config) {
752 		if (x86_quirks->mach_find_smp_config(reserve))
753 			return;
754 	}
755 	/*
756 	 * FIXME: Linux assumes you have 640K of base ram..
757 	 * this continues the error...
758 	 *
759 	 * 1) Scan the bottom 1K for a signature
760 	 * 2) Scan the top 1K of base RAM
761 	 * 3) Scan the 64K of bios
762 	 */
763 	if (smp_scan_config(0x0, 0x400, reserve) ||
764 	    smp_scan_config(639 * 0x400, 0x400, reserve) ||
765 	    smp_scan_config(0xF0000, 0x10000, reserve))
766 		return;
767 	/*
768 	 * If it is an SMP machine we should know now, unless the
769 	 * configuration is in an EISA/MCA bus machine with an
770 	 * extended bios data area.
771 	 *
772 	 * there is a real-mode segmented pointer pointing to the
773 	 * 4K EBDA area at 0x40E, calculate and scan it here.
774 	 *
775 	 * NOTE! There are Linux loaders that will corrupt the EBDA
776 	 * area, and as such this kind of SMP config may be less
777 	 * trustworthy, simply because the SMP table may have been
778 	 * stomped on during early boot. These loaders are buggy and
779 	 * should be fixed.
780 	 *
781 	 * MP1.4 SPEC states to only scan first 1K of 4K EBDA.
782 	 */
783 
784 	address = get_bios_ebda();
785 	if (address)
786 		smp_scan_config(address, 0x400, reserve);
787 }
788 
789 void __init early_find_smp_config(void)
790 {
791 	__find_smp_config(0);
792 }
793 
794 void __init find_smp_config(void)
795 {
796 	__find_smp_config(1);
797 }
798 
799 #ifdef CONFIG_X86_IO_APIC
800 static u8 __initdata irq_used[MAX_IRQ_SOURCES];
801 
802 static int  __init get_MP_intsrc_index(struct mpc_intsrc *m)
803 {
804 	int i;
805 
806 	if (m->irqtype != mp_INT)
807 		return 0;
808 
809 	if (m->irqflag != 0x0f)
810 		return 0;
811 
812 	/* not legacy */
813 
814 	for (i = 0; i < mp_irq_entries; i++) {
815 		if (mp_irqs[i].irqtype != mp_INT)
816 			continue;
817 
818 		if (mp_irqs[i].irqflag != 0x0f)
819 			continue;
820 
821 		if (mp_irqs[i].srcbus != m->srcbus)
822 			continue;
823 		if (mp_irqs[i].srcbusirq != m->srcbusirq)
824 			continue;
825 		if (irq_used[i]) {
826 			/* already claimed */
827 			return -2;
828 		}
829 		irq_used[i] = 1;
830 		return i;
831 	}
832 
833 	/* not found */
834 	return -1;
835 }
836 
837 #define SPARE_SLOT_NUM 20
838 
839 static struct mpc_intsrc __initdata *m_spare[SPARE_SLOT_NUM];
840 
841 static void __init check_irq_src(struct mpc_intsrc *m, int *nr_m_spare)
842 {
843 	int i;
844 
845 	apic_printk(APIC_VERBOSE, "OLD ");
846 	print_MP_intsrc_info(m);
847 
848 	i = get_MP_intsrc_index(m);
849 	if (i > 0) {
850 		assign_to_mpc_intsrc(&mp_irqs[i], m);
851 		apic_printk(APIC_VERBOSE, "NEW ");
852 		print_mp_irq_info(&mp_irqs[i]);
853 		return;
854 	}
855 	if (!i) {
856 		/* legacy, do nothing */
857 		return;
858 	}
859 	if (*nr_m_spare < SPARE_SLOT_NUM) {
860 		/*
861 		 * not found (-1), or duplicated (-2) are invalid entries,
862 		 * we need to use the slot later
863 		 */
864 		m_spare[*nr_m_spare] = m;
865 		*nr_m_spare += 1;
866 	}
867 }
868 #else /* CONFIG_X86_IO_APIC */
869 static
870 inline void __init check_irq_src(struct mpc_intsrc *m, int *nr_m_spare) {}
871 #endif /* CONFIG_X86_IO_APIC */
872 
873 static int check_slot(unsigned long mpc_new_phys, unsigned long mpc_new_length,
874 		      int count)
875 {
876 	if (!mpc_new_phys) {
877 		pr_info("No spare slots, try to append...take your risk, "
878 			"new mpc_length %x\n", count);
879 	} else {
880 		if (count <= mpc_new_length)
881 			pr_info("No spare slots, try to append..., "
882 				"new mpc_length %x\n", count);
883 		else {
884 			pr_err("mpc_new_length %lx is too small\n",
885 				mpc_new_length);
886 			return -1;
887 		}
888 	}
889 
890 	return 0;
891 }
892 
893 static int  __init replace_intsrc_all(struct mpc_table *mpc,
894 					unsigned long mpc_new_phys,
895 					unsigned long mpc_new_length)
896 {
897 #ifdef CONFIG_X86_IO_APIC
898 	int i;
899 #endif
900 	int count = sizeof(*mpc);
901 	int nr_m_spare = 0;
902 	unsigned char *mpt = ((unsigned char *)mpc) + count;
903 
904 	printk(KERN_INFO "mpc_length %x\n", mpc->length);
905 	while (count < mpc->length) {
906 		switch (*mpt) {
907 		case MP_PROCESSOR:
908 			skip_entry(&mpt, &count, sizeof(struct mpc_cpu));
909 			break;
910 		case MP_BUS:
911 			skip_entry(&mpt, &count, sizeof(struct mpc_bus));
912 			break;
913 		case MP_IOAPIC:
914 			skip_entry(&mpt, &count, sizeof(struct mpc_ioapic));
915 			break;
916 		case MP_INTSRC:
917 			check_irq_src((struct mpc_intsrc *)mpt, &nr_m_spare);
918 			skip_entry(&mpt, &count, sizeof(struct mpc_intsrc));
919 			break;
920 		case MP_LINTSRC:
921 			skip_entry(&mpt, &count, sizeof(struct mpc_lintsrc));
922 			break;
923 		default:
924 			/* wrong mptable */
925 			smp_dump_mptable(mpc, mpt);
926 			goto out;
927 		}
928 	}
929 
930 #ifdef CONFIG_X86_IO_APIC
931 	for (i = 0; i < mp_irq_entries; i++) {
932 		if (irq_used[i])
933 			continue;
934 
935 		if (mp_irqs[i].irqtype != mp_INT)
936 			continue;
937 
938 		if (mp_irqs[i].irqflag != 0x0f)
939 			continue;
940 
941 		if (nr_m_spare > 0) {
942 			apic_printk(APIC_VERBOSE, "*NEW* found\n");
943 			nr_m_spare--;
944 			assign_to_mpc_intsrc(&mp_irqs[i], m_spare[nr_m_spare]);
945 			m_spare[nr_m_spare] = NULL;
946 		} else {
947 			struct mpc_intsrc *m = (struct mpc_intsrc *)mpt;
948 			count += sizeof(struct mpc_intsrc);
949 			if (!check_slot(mpc_new_phys, mpc_new_length, count))
950 				goto out;
951 			assign_to_mpc_intsrc(&mp_irqs[i], m);
952 			mpc->length = count;
953 			mpt += sizeof(struct mpc_intsrc);
954 		}
955 		print_mp_irq_info(&mp_irqs[i]);
956 	}
957 #endif
958 out:
959 	/* update checksum */
960 	mpc->checksum = 0;
961 	mpc->checksum -= mpf_checksum((unsigned char *)mpc, mpc->length);
962 
963 	return 0;
964 }
965 
966 static int __initdata enable_update_mptable;
967 
968 static int __init update_mptable_setup(char *str)
969 {
970 	enable_update_mptable = 1;
971 	return 0;
972 }
973 early_param("update_mptable", update_mptable_setup);
974 
975 static unsigned long __initdata mpc_new_phys;
976 static unsigned long mpc_new_length __initdata = 4096;
977 
978 /* alloc_mptable or alloc_mptable=4k */
979 static int __initdata alloc_mptable;
980 static int __init parse_alloc_mptable_opt(char *p)
981 {
982 	enable_update_mptable = 1;
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