xref: /linux/arch/x86/kernel/mpparse.c (revision b233b28eac0cc37d07c2d007ea08c86c778c5af4)
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 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 <mach_apic.h>
33 #ifdef CONFIG_X86_32
34 #include <mach_apicdef.h>
35 #include <mach_mpparse.h>
36 #endif
37 
38 /*
39  * Checksum an MP configuration block.
40  */
41 
42 static int __init mpf_checksum(unsigned char *mp, int len)
43 {
44 	int sum = 0;
45 
46 	while (len--)
47 		sum += *mp++;
48 
49 	return sum & 0xFF;
50 }
51 
52 static void __init MP_processor_info(struct mpc_cpu *m)
53 {
54 	int apicid;
55 	char *bootup_cpu = "";
56 
57 	if (!(m->cpuflag & CPU_ENABLED)) {
58 		disabled_cpus++;
59 		return;
60 	}
61 
62 	if (x86_quirks->mpc_apic_id)
63 		apicid = x86_quirks->mpc_apic_id(m);
64 	else
65 		apicid = m->apicid;
66 
67 	if (m->cpuflag & CPU_BOOTPROCESSOR) {
68 		bootup_cpu = " (Bootup-CPU)";
69 		boot_cpu_physical_apicid = m->apicid;
70 	}
71 
72 	printk(KERN_INFO "Processor #%d%s\n", m->apicid, bootup_cpu);
73 	generic_processor_info(apicid, m->apicver);
74 }
75 
76 #ifdef CONFIG_X86_IO_APIC
77 static void __init MP_bus_info(struct mpc_bus *m)
78 {
79 	char str[7];
80 	memcpy(str, m->bustype, 6);
81 	str[6] = 0;
82 
83 	if (x86_quirks->mpc_oem_bus_info)
84 		x86_quirks->mpc_oem_bus_info(m, str);
85 	else
86 		apic_printk(APIC_VERBOSE, "Bus #%d is %s\n", m->busid, str);
87 
88 #if MAX_MP_BUSSES < 256
89 	if (m->busid >= MAX_MP_BUSSES) {
90 		printk(KERN_WARNING "MP table busid value (%d) for bustype %s "
91 		       " is too large, max. supported is %d\n",
92 		       m->busid, str, MAX_MP_BUSSES - 1);
93 		return;
94 	}
95 #endif
96 
97 	if (strncmp(str, BUSTYPE_ISA, sizeof(BUSTYPE_ISA) - 1) == 0) {
98 		set_bit(m->busid, mp_bus_not_pci);
99 #if defined(CONFIG_EISA) || defined(CONFIG_MCA)
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_quirks->mpc_oem_pci_bus)
104 			x86_quirks->mpc_oem_pci_bus(m);
105 
106 		clear_bit(m->busid, mp_bus_not_pci);
107 #if defined(CONFIG_EISA) || defined(CONFIG_MCA)
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 	} else if (strncmp(str, BUSTYPE_MCA, sizeof(BUSTYPE_MCA) - 1) == 0) {
112 		mp_bus_id_to_type[m->busid] = MP_BUS_MCA;
113 #endif
114 	} else
115 		printk(KERN_WARNING "Unknown bustype %s - ignoring\n", str);
116 }
117 #endif
118 
119 #ifdef CONFIG_X86_IO_APIC
120 
121 static int bad_ioapic(unsigned long address)
122 {
123 	if (nr_ioapics >= MAX_IO_APICS) {
124 		printk(KERN_ERR "ERROR: Max # of I/O APICs (%d) exceeded "
125 		       "(found %d)\n", MAX_IO_APICS, nr_ioapics);
126 		panic("Recompile kernel with bigger MAX_IO_APICS!\n");
127 	}
128 	if (!address) {
129 		printk(KERN_ERR "WARNING: Bogus (zero) I/O APIC address"
130 		       " found in table, skipping!\n");
131 		return 1;
132 	}
133 	return 0;
134 }
135 
136 static void __init MP_ioapic_info(struct mpc_ioapic *m)
137 {
138 	if (!(m->flags & MPC_APIC_USABLE))
139 		return;
140 
141 	printk(KERN_INFO "I/O APIC #%d Version %d at 0x%X.\n",
142 	       m->apicid, m->apicver, m->apicaddr);
143 
144 	if (bad_ioapic(m->apicaddr))
145 		return;
146 
147 	mp_ioapics[nr_ioapics].mp_apicaddr = m->apicaddr;
148 	mp_ioapics[nr_ioapics].mp_apicid = m->apicid;
149 	mp_ioapics[nr_ioapics].mp_type = m->type;
150 	mp_ioapics[nr_ioapics].mp_apicver = m->apicver;
151 	mp_ioapics[nr_ioapics].mp_flags = m->flags;
152 	nr_ioapics++;
153 }
154 
155 static void print_MP_intsrc_info(struct mpc_intsrc *m)
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 		m->irqtype, m->irqflag & 3, (m->irqflag >> 2) & 3, m->srcbus,
160 		m->srcbusirq, m->dstapic, m->dstirq);
161 }
162 
163 static void __init print_mp_irq_info(struct mp_config_intsrc *mp_irq)
164 {
165 	apic_printk(APIC_VERBOSE, "Int: type %d, pol %d, trig %d, bus %02x,"
166 		" IRQ %02x, APIC ID %x, APIC INT %02x\n",
167 		mp_irq->mp_irqtype, mp_irq->mp_irqflag & 3,
168 		(mp_irq->mp_irqflag >> 2) & 3, mp_irq->mp_srcbus,
169 		mp_irq->mp_srcbusirq, mp_irq->mp_dstapic, mp_irq->mp_dstirq);
170 }
171 
172 static void __init assign_to_mp_irq(struct mpc_intsrc *m,
173 				    struct mp_config_intsrc *mp_irq)
174 {
175 	mp_irq->mp_dstapic = m->dstapic;
176 	mp_irq->mp_type = m->type;
177 	mp_irq->mp_irqtype = m->irqtype;
178 	mp_irq->mp_irqflag = m->irqflag;
179 	mp_irq->mp_srcbus = m->srcbus;
180 	mp_irq->mp_srcbusirq = m->srcbusirq;
181 	mp_irq->mp_dstirq = m->dstirq;
182 }
183 
184 static void __init assign_to_mpc_intsrc(struct mp_config_intsrc *mp_irq,
185 					struct mpc_intsrc *m)
186 {
187 	m->dstapic = mp_irq->mp_dstapic;
188 	m->type = mp_irq->mp_type;
189 	m->irqtype = mp_irq->mp_irqtype;
190 	m->irqflag = mp_irq->mp_irqflag;
191 	m->srcbus = mp_irq->mp_srcbus;
192 	m->srcbusirq = mp_irq->mp_srcbusirq;
193 	m->dstirq = mp_irq->mp_dstirq;
194 }
195 
196 static int __init mp_irq_mpc_intsrc_cmp(struct mp_config_intsrc *mp_irq,
197 					struct mpc_intsrc *m)
198 {
199 	if (mp_irq->mp_dstapic != m->dstapic)
200 		return 1;
201 	if (mp_irq->mp_type != m->type)
202 		return 2;
203 	if (mp_irq->mp_irqtype != m->irqtype)
204 		return 3;
205 	if (mp_irq->mp_irqflag != m->irqflag)
206 		return 4;
207 	if (mp_irq->mp_srcbus != m->srcbus)
208 		return 5;
209 	if (mp_irq->mp_srcbusirq != m->srcbusirq)
210 		return 6;
211 	if (mp_irq->mp_dstirq != m->dstirq)
212 		return 7;
213 
214 	return 0;
215 }
216 
217 static void __init MP_intsrc_info(struct mpc_intsrc *m)
218 {
219 	int i;
220 
221 	print_MP_intsrc_info(m);
222 
223 	for (i = 0; i < mp_irq_entries; i++) {
224 		if (!mp_irq_mpc_intsrc_cmp(&mp_irqs[i], m))
225 			return;
226 	}
227 
228 	assign_to_mp_irq(m, &mp_irqs[mp_irq_entries]);
229 	if (++mp_irq_entries == MAX_IRQ_SOURCES)
230 		panic("Max # of irq sources exceeded!!\n");
231 }
232 
233 #endif
234 
235 static void __init MP_lintsrc_info(struct mpc_lintsrc *m)
236 {
237 	apic_printk(APIC_VERBOSE, "Lint: type %d, pol %d, trig %d, bus %02x,"
238 		" IRQ %02x, APIC ID %x, APIC LINT %02x\n",
239 		m->irqtype, m->irqflag & 3, (m->irqflag >> 2) & 3, m->srcbusid,
240 		m->srcbusirq, m->destapic, m->destapiclint);
241 }
242 
243 /*
244  * Read/parse the MPC
245  */
246 
247 static int __init smp_check_mpc(struct mpc_table *mpc, char *oem, char *str)
248 {
249 
250 	if (memcmp(mpc->signature, MPC_SIGNATURE, 4)) {
251 		printk(KERN_ERR "MPTABLE: bad signature [%c%c%c%c]!\n",
252 		       mpc->signature[0], mpc->signature[1],
253 		       mpc->signature[2], mpc->signature[3]);
254 		return 0;
255 	}
256 	if (mpf_checksum((unsigned char *)mpc, mpc->length)) {
257 		printk(KERN_ERR "MPTABLE: checksum error!\n");
258 		return 0;
259 	}
260 	if (mpc->spec != 0x01 && mpc->spec != 0x04) {
261 		printk(KERN_ERR "MPTABLE: bad table version (%d)!!\n",
262 		       mpc->spec);
263 		return 0;
264 	}
265 	if (!mpc->lapic) {
266 		printk(KERN_ERR "MPTABLE: null local APIC address!\n");
267 		return 0;
268 	}
269 	memcpy(oem, mpc->oem, 8);
270 	oem[8] = 0;
271 	printk(KERN_INFO "MPTABLE: OEM ID: %s\n", oem);
272 
273 	memcpy(str, mpc->productid, 12);
274 	str[12] = 0;
275 
276 	printk(KERN_INFO "MPTABLE: Product ID: %s\n", str);
277 
278 	printk(KERN_INFO "MPTABLE: APIC at: 0x%X\n", mpc->lapic);
279 
280 	return 1;
281 }
282 
283 static int __init smp_read_mpc(struct mpc_table *mpc, unsigned early)
284 {
285 	char str[16];
286 	char oem[10];
287 
288 	int count = sizeof(*mpc);
289 	unsigned char *mpt = ((unsigned char *)mpc) + count;
290 
291 	if (!smp_check_mpc(mpc, oem, str))
292 		return 0;
293 
294 #ifdef CONFIG_X86_32
295 	/*
296 	 * need to make sure summit and es7000's mps_oem_check is safe to be
297 	 * called early via genericarch 's mps_oem_check
298 	 */
299 	if (early) {
300 #ifdef CONFIG_X86_NUMAQ
301 		numaq_mps_oem_check(mpc, oem, str);
302 #endif
303 	} else
304 		mps_oem_check(mpc, oem, str);
305 #endif
306 	/* save the local APIC address, it might be non-default */
307 	if (!acpi_lapic)
308 		mp_lapic_addr = mpc->lapic;
309 
310 	if (early)
311 		return 1;
312 
313 	if (mpc->oemptr && x86_quirks->smp_read_mpc_oem) {
314 		struct mpc_oemtable *oem_table = (void *)(long)mpc->oemptr;
315 		x86_quirks->smp_read_mpc_oem(oem_table, mpc->oemsize);
316 	}
317 
318 	/*
319 	 *      Now process the configuration blocks.
320 	 */
321 	if (x86_quirks->mpc_record)
322 		*x86_quirks->mpc_record = 0;
323 
324 	while (count < mpc->length) {
325 		switch (*mpt) {
326 		case MP_PROCESSOR:
327 			{
328 				struct mpc_cpu *m = (struct mpc_cpu *)mpt;
329 				/* ACPI may have already provided this data */
330 				if (!acpi_lapic)
331 					MP_processor_info(m);
332 				mpt += sizeof(*m);
333 				count += sizeof(*m);
334 				break;
335 			}
336 		case MP_BUS:
337 			{
338 				struct mpc_bus *m = (struct mpc_bus *)mpt;
339 #ifdef CONFIG_X86_IO_APIC
340 				MP_bus_info(m);
341 #endif
342 				mpt += sizeof(*m);
343 				count += sizeof(*m);
344 				break;
345 			}
346 		case MP_IOAPIC:
347 			{
348 #ifdef CONFIG_X86_IO_APIC
349 				struct mpc_ioapic *m = (struct mpc_ioapic *)mpt;
350 				MP_ioapic_info(m);
351 #endif
352 				mpt += sizeof(struct mpc_ioapic);
353 				count += sizeof(struct mpc_ioapic);
354 				break;
355 			}
356 		case MP_INTSRC:
357 			{
358 #ifdef CONFIG_X86_IO_APIC
359 				struct mpc_intsrc *m = (struct mpc_intsrc *)mpt;
360 
361 				MP_intsrc_info(m);
362 #endif
363 				mpt += sizeof(struct mpc_intsrc);
364 				count += sizeof(struct mpc_intsrc);
365 				break;
366 			}
367 		case MP_LINTSRC:
368 			{
369 				struct mpc_lintsrc *m =
370 				    (struct mpc_lintsrc *)mpt;
371 				MP_lintsrc_info(m);
372 				mpt += sizeof(*m);
373 				count += sizeof(*m);
374 				break;
375 			}
376 		default:
377 			/* wrong mptable */
378 			printk(KERN_ERR "Your mptable is wrong, contact your HW vendor!\n");
379 			printk(KERN_ERR "type %x\n", *mpt);
380 			print_hex_dump(KERN_ERR, "  ", DUMP_PREFIX_ADDRESS, 16,
381 					1, mpc, mpc->length, 1);
382 			count = mpc->length;
383 			break;
384 		}
385 		if (x86_quirks->mpc_record)
386 			(*x86_quirks->mpc_record)++;
387 	}
388 
389 #ifdef CONFIG_X86_GENERICARCH
390        generic_bigsmp_probe();
391 #endif
392 
393 #ifdef CONFIG_X86_32
394 	setup_apic_routing();
395 #endif
396 	if (!num_processors)
397 		printk(KERN_ERR "MPTABLE: no processors registered!\n");
398 	return num_processors;
399 }
400 
401 #ifdef CONFIG_X86_IO_APIC
402 
403 static int __init ELCR_trigger(unsigned int irq)
404 {
405 	unsigned int port;
406 
407 	port = 0x4d0 + (irq >> 3);
408 	return (inb(port) >> (irq & 7)) & 1;
409 }
410 
411 static void __init construct_default_ioirq_mptable(int mpc_default_type)
412 {
413 	struct mpc_intsrc intsrc;
414 	int i;
415 	int ELCR_fallback = 0;
416 
417 	intsrc.type = MP_INTSRC;
418 	intsrc.irqflag = 0;	/* conforming */
419 	intsrc.srcbus = 0;
420 	intsrc.dstapic = mp_ioapics[0].mp_apicid;
421 
422 	intsrc.irqtype = mp_INT;
423 
424 	/*
425 	 *  If true, we have an ISA/PCI system with no IRQ entries
426 	 *  in the MP table. To prevent the PCI interrupts from being set up
427 	 *  incorrectly, we try to use the ELCR. The sanity check to see if
428 	 *  there is good ELCR data is very simple - IRQ0, 1, 2 and 13 can
429 	 *  never be level sensitive, so we simply see if the ELCR agrees.
430 	 *  If it does, we assume it's valid.
431 	 */
432 	if (mpc_default_type == 5) {
433 		printk(KERN_INFO "ISA/PCI bus type with no IRQ information... "
434 		       "falling back to ELCR\n");
435 
436 		if (ELCR_trigger(0) || ELCR_trigger(1) || ELCR_trigger(2) ||
437 		    ELCR_trigger(13))
438 			printk(KERN_ERR "ELCR contains invalid data... "
439 			       "not using ELCR\n");
440 		else {
441 			printk(KERN_INFO
442 			       "Using ELCR to identify PCI interrupts\n");
443 			ELCR_fallback = 1;
444 		}
445 	}
446 
447 	for (i = 0; i < 16; i++) {
448 		switch (mpc_default_type) {
449 		case 2:
450 			if (i == 0 || i == 13)
451 				continue;	/* IRQ0 & IRQ13 not connected */
452 			/* fall through */
453 		default:
454 			if (i == 2)
455 				continue;	/* IRQ2 is never connected */
456 		}
457 
458 		if (ELCR_fallback) {
459 			/*
460 			 *  If the ELCR indicates a level-sensitive interrupt, we
461 			 *  copy that information over to the MP table in the
462 			 *  irqflag field (level sensitive, active high polarity).
463 			 */
464 			if (ELCR_trigger(i))
465 				intsrc.irqflag = 13;
466 			else
467 				intsrc.irqflag = 0;
468 		}
469 
470 		intsrc.srcbusirq = i;
471 		intsrc.dstirq = i ? i : 2;	/* IRQ0 to INTIN2 */
472 		MP_intsrc_info(&intsrc);
473 	}
474 
475 	intsrc.irqtype = mp_ExtINT;
476 	intsrc.srcbusirq = 0;
477 	intsrc.dstirq = 0;	/* 8259A to INTIN0 */
478 	MP_intsrc_info(&intsrc);
479 }
480 
481 
482 static void __init construct_ioapic_table(int mpc_default_type)
483 {
484 	struct mpc_ioapic ioapic;
485 	struct mpc_bus bus;
486 
487 	bus.type = MP_BUS;
488 	bus.busid = 0;
489 	switch (mpc_default_type) {
490 	default:
491 		printk(KERN_ERR "???\nUnknown standard configuration %d\n",
492 		       mpc_default_type);
493 		/* fall through */
494 	case 1:
495 	case 5:
496 		memcpy(bus.bustype, "ISA   ", 6);
497 		break;
498 	case 2:
499 	case 6:
500 	case 3:
501 		memcpy(bus.bustype, "EISA  ", 6);
502 		break;
503 	case 4:
504 	case 7:
505 		memcpy(bus.bustype, "MCA   ", 6);
506 	}
507 	MP_bus_info(&bus);
508 	if (mpc_default_type > 4) {
509 		bus.busid = 1;
510 		memcpy(bus.bustype, "PCI   ", 6);
511 		MP_bus_info(&bus);
512 	}
513 
514 	ioapic.type = MP_IOAPIC;
515 	ioapic.apicid = 2;
516 	ioapic.apicver = mpc_default_type > 4 ? 0x10 : 0x01;
517 	ioapic.flags = MPC_APIC_USABLE;
518 	ioapic.apicaddr = 0xFEC00000;
519 	MP_ioapic_info(&ioapic);
520 
521 	/*
522 	 * We set up most of the low 16 IO-APIC pins according to MPS rules.
523 	 */
524 	construct_default_ioirq_mptable(mpc_default_type);
525 }
526 #else
527 static inline void __init construct_ioapic_table(int mpc_default_type) { }
528 #endif
529 
530 static inline void __init construct_default_ISA_mptable(int mpc_default_type)
531 {
532 	struct mpc_cpu processor;
533 	struct mpc_lintsrc lintsrc;
534 	int linttypes[2] = { mp_ExtINT, mp_NMI };
535 	int i;
536 
537 	/*
538 	 * local APIC has default address
539 	 */
540 	mp_lapic_addr = APIC_DEFAULT_PHYS_BASE;
541 
542 	/*
543 	 * 2 CPUs, numbered 0 & 1.
544 	 */
545 	processor.type = MP_PROCESSOR;
546 	/* Either an integrated APIC or a discrete 82489DX. */
547 	processor.apicver = mpc_default_type > 4 ? 0x10 : 0x01;
548 	processor.cpuflag = CPU_ENABLED;
549 	processor.cpufeature = (boot_cpu_data.x86 << 8) |
550 	    (boot_cpu_data.x86_model << 4) | boot_cpu_data.x86_mask;
551 	processor.featureflag = boot_cpu_data.x86_capability[0];
552 	processor.reserved[0] = 0;
553 	processor.reserved[1] = 0;
554 	for (i = 0; i < 2; i++) {
555 		processor.apicid = i;
556 		MP_processor_info(&processor);
557 	}
558 
559 	construct_ioapic_table(mpc_default_type);
560 
561 	lintsrc.type = MP_LINTSRC;
562 	lintsrc.irqflag = 0;		/* conforming */
563 	lintsrc.srcbusid = 0;
564 	lintsrc.srcbusirq = 0;
565 	lintsrc.destapic = MP_APIC_ALL;
566 	for (i = 0; i < 2; i++) {
567 		lintsrc.irqtype = linttypes[i];
568 		lintsrc.destapiclint = i;
569 		MP_lintsrc_info(&lintsrc);
570 	}
571 }
572 
573 static struct intel_mp_floating *mpf_found;
574 
575 /*
576  * Scan the memory blocks for an SMP configuration block.
577  */
578 static void __init __get_smp_config(unsigned int early)
579 {
580 	struct intel_mp_floating *mpf = mpf_found;
581 
582 	if (!mpf)
583 		return;
584 
585 	if (acpi_lapic && early)
586 		return;
587 
588 	/*
589 	 * MPS doesn't support hyperthreading, aka only have
590 	 * thread 0 apic id in MPS table
591 	 */
592 	if (acpi_lapic && acpi_ioapic)
593 		return;
594 
595 	if (x86_quirks->mach_get_smp_config) {
596 		if (x86_quirks->mach_get_smp_config(early))
597 			return;
598 	}
599 
600 	printk(KERN_INFO "Intel MultiProcessor Specification v1.%d\n",
601 	       mpf->mpf_specification);
602 #if defined(CONFIG_X86_LOCAL_APIC) && defined(CONFIG_X86_32)
603 	if (mpf->mpf_feature2 & (1 << 7)) {
604 		printk(KERN_INFO "    IMCR and PIC compatibility mode.\n");
605 		pic_mode = 1;
606 	} else {
607 		printk(KERN_INFO "    Virtual Wire compatibility mode.\n");
608 		pic_mode = 0;
609 	}
610 #endif
611 	/*
612 	 * Now see if we need to read further.
613 	 */
614 	if (mpf->mpf_feature1 != 0) {
615 		if (early) {
616 			/*
617 			 * local APIC has default address
618 			 */
619 			mp_lapic_addr = APIC_DEFAULT_PHYS_BASE;
620 			return;
621 		}
622 
623 		printk(KERN_INFO "Default MP configuration #%d\n",
624 		       mpf->mpf_feature1);
625 		construct_default_ISA_mptable(mpf->mpf_feature1);
626 
627 	} else if (mpf->mpf_physptr) {
628 
629 		/*
630 		 * Read the physical hardware table.  Anything here will
631 		 * override the defaults.
632 		 */
633 		if (!smp_read_mpc(phys_to_virt(mpf->mpf_physptr), early)) {
634 #ifdef CONFIG_X86_LOCAL_APIC
635 			smp_found_config = 0;
636 #endif
637 			printk(KERN_ERR
638 			       "BIOS bug, MP table errors detected!...\n");
639 			printk(KERN_ERR "... disabling SMP support. "
640 			       "(tell your hw vendor)\n");
641 			return;
642 		}
643 
644 		if (early)
645 			return;
646 #ifdef CONFIG_X86_IO_APIC
647 		/*
648 		 * If there are no explicit MP IRQ entries, then we are
649 		 * broken.  We set up most of the low 16 IO-APIC pins to
650 		 * ISA defaults and hope it will work.
651 		 */
652 		if (!mp_irq_entries) {
653 			struct mpc_bus bus;
654 
655 			printk(KERN_ERR "BIOS bug, no explicit IRQ entries, "
656 			       "using default mptable. "
657 			       "(tell your hw vendor)\n");
658 
659 			bus.type = MP_BUS;
660 			bus.busid = 0;
661 			memcpy(bus.bustype, "ISA   ", 6);
662 			MP_bus_info(&bus);
663 
664 			construct_default_ioirq_mptable(0);
665 		}
666 #endif
667 	} else
668 		BUG();
669 
670 	if (!early)
671 		printk(KERN_INFO "Processors: %d\n", num_processors);
672 	/*
673 	 * Only use the first configuration found.
674 	 */
675 }
676 
677 void __init early_get_smp_config(void)
678 {
679 	__get_smp_config(1);
680 }
681 
682 void __init get_smp_config(void)
683 {
684 	__get_smp_config(0);
685 }
686 
687 static int __init smp_scan_config(unsigned long base, unsigned long length,
688 				  unsigned reserve)
689 {
690 	unsigned int *bp = phys_to_virt(base);
691 	struct intel_mp_floating *mpf;
692 
693 	apic_printk(APIC_VERBOSE, "Scan SMP from %p for %ld bytes.\n",
694 			bp, length);
695 	BUILD_BUG_ON(sizeof(*mpf) != 16);
696 
697 	while (length > 0) {
698 		mpf = (struct intel_mp_floating *)bp;
699 		if ((*bp == SMP_MAGIC_IDENT) &&
700 		    (mpf->mpf_length == 1) &&
701 		    !mpf_checksum((unsigned char *)bp, 16) &&
702 		    ((mpf->mpf_specification == 1)
703 		     || (mpf->mpf_specification == 4))) {
704 #ifdef CONFIG_X86_LOCAL_APIC
705 			smp_found_config = 1;
706 #endif
707 			mpf_found = mpf;
708 
709 			printk(KERN_INFO "found SMP MP-table at [%p] %08lx\n",
710 			       mpf, virt_to_phys(mpf));
711 
712 			if (!reserve)
713 				return 1;
714 			reserve_bootmem_generic(virt_to_phys(mpf), PAGE_SIZE,
715 					BOOTMEM_DEFAULT);
716 			if (mpf->mpf_physptr) {
717 				unsigned long size = PAGE_SIZE;
718 #ifdef CONFIG_X86_32
719 				/*
720 				 * We cannot access to MPC table to compute
721 				 * table size yet, as only few megabytes from
722 				 * the bottom is mapped now.
723 				 * PC-9800's MPC table places on the very last
724 				 * of physical memory; so that simply reserving
725 				 * PAGE_SIZE from mpg->mpf_physptr yields BUG()
726 				 * in reserve_bootmem.
727 				 */
728 				unsigned long end = max_low_pfn * PAGE_SIZE;
729 				if (mpf->mpf_physptr + size > end)
730 					size = end - mpf->mpf_physptr;
731 #endif
732 				reserve_bootmem_generic(mpf->mpf_physptr, size,
733 						BOOTMEM_DEFAULT);
734 			}
735 
736 			return 1;
737 		}
738 		bp += 4;
739 		length -= 16;
740 	}
741 	return 0;
742 }
743 
744 static void __init __find_smp_config(unsigned int reserve)
745 {
746 	unsigned int address;
747 
748 	if (x86_quirks->mach_find_smp_config) {
749 		if (x86_quirks->mach_find_smp_config(reserve))
750 			return;
751 	}
752 	/*
753 	 * FIXME: Linux assumes you have 640K of base ram..
754 	 * this continues the error...
755 	 *
756 	 * 1) Scan the bottom 1K for a signature
757 	 * 2) Scan the top 1K of base RAM
758 	 * 3) Scan the 64K of bios
759 	 */
760 	if (smp_scan_config(0x0, 0x400, reserve) ||
761 	    smp_scan_config(639 * 0x400, 0x400, reserve) ||
762 	    smp_scan_config(0xF0000, 0x10000, reserve))
763 		return;
764 	/*
765 	 * If it is an SMP machine we should know now, unless the
766 	 * configuration is in an EISA/MCA bus machine with an
767 	 * extended bios data area.
768 	 *
769 	 * there is a real-mode segmented pointer pointing to the
770 	 * 4K EBDA area at 0x40E, calculate and scan it here.
771 	 *
772 	 * NOTE! There are Linux loaders that will corrupt the EBDA
773 	 * area, and as such this kind of SMP config may be less
774 	 * trustworthy, simply because the SMP table may have been
775 	 * stomped on during early boot. These loaders are buggy and
776 	 * should be fixed.
777 	 *
778 	 * MP1.4 SPEC states to only scan first 1K of 4K EBDA.
779 	 */
780 
781 	address = get_bios_ebda();
782 	if (address)
783 		smp_scan_config(address, 0x400, reserve);
784 }
785 
786 void __init early_find_smp_config(void)
787 {
788 	__find_smp_config(0);
789 }
790 
791 void __init find_smp_config(void)
792 {
793 	__find_smp_config(1);
794 }
795 
796 #ifdef CONFIG_X86_IO_APIC
797 static u8 __initdata irq_used[MAX_IRQ_SOURCES];
798 
799 static int  __init get_MP_intsrc_index(struct mpc_intsrc *m)
800 {
801 	int i;
802 
803 	if (m->irqtype != mp_INT)
804 		return 0;
805 
806 	if (m->irqflag != 0x0f)
807 		return 0;
808 
809 	/* not legacy */
810 
811 	for (i = 0; i < mp_irq_entries; i++) {
812 		if (mp_irqs[i].mp_irqtype != mp_INT)
813 			continue;
814 
815 		if (mp_irqs[i].mp_irqflag != 0x0f)
816 			continue;
817 
818 		if (mp_irqs[i].mp_srcbus != m->srcbus)
819 			continue;
820 		if (mp_irqs[i].mp_srcbusirq != m->srcbusirq)
821 			continue;
822 		if (irq_used[i]) {
823 			/* already claimed */
824 			return -2;
825 		}
826 		irq_used[i] = 1;
827 		return i;
828 	}
829 
830 	/* not found */
831 	return -1;
832 }
833 
834 #define SPARE_SLOT_NUM 20
835 
836 static struct mpc_intsrc __initdata *m_spare[SPARE_SLOT_NUM];
837 #endif
838 
839 static int  __init replace_intsrc_all(struct mpc_table *mpc,
840 					unsigned long mpc_new_phys,
841 					unsigned long mpc_new_length)
842 {
843 #ifdef CONFIG_X86_IO_APIC
844 	int i;
845 	int nr_m_spare = 0;
846 #endif
847 
848 	int count = sizeof(*mpc);
849 	unsigned char *mpt = ((unsigned char *)mpc) + count;
850 
851 	printk(KERN_INFO "mpc_length %x\n", mpc->length);
852 	while (count < mpc->length) {
853 		switch (*mpt) {
854 		case MP_PROCESSOR:
855 			{
856 				struct mpc_cpu *m = (struct mpc_cpu *)mpt;
857 				mpt += sizeof(*m);
858 				count += sizeof(*m);
859 				break;
860 			}
861 		case MP_BUS:
862 			{
863 				struct mpc_bus *m = (struct mpc_bus *)mpt;
864 				mpt += sizeof(*m);
865 				count += sizeof(*m);
866 				break;
867 			}
868 		case MP_IOAPIC:
869 			{
870 				mpt += sizeof(struct mpc_ioapic);
871 				count += sizeof(struct mpc_ioapic);
872 				break;
873 			}
874 		case MP_INTSRC:
875 			{
876 #ifdef CONFIG_X86_IO_APIC
877 				struct mpc_intsrc *m = (struct mpc_intsrc *)mpt;
878 
879 				printk(KERN_INFO "OLD ");
880 				print_MP_intsrc_info(m);
881 				i = get_MP_intsrc_index(m);
882 				if (i > 0) {
883 					assign_to_mpc_intsrc(&mp_irqs[i], m);
884 					printk(KERN_INFO "NEW ");
885 					print_mp_irq_info(&mp_irqs[i]);
886 				} else if (!i) {
887 					/* legacy, do nothing */
888 				} else if (nr_m_spare < SPARE_SLOT_NUM) {
889 					/*
890 					 * not found (-1), or duplicated (-2)
891 					 * are invalid entries,
892 					 * we need to use the slot  later
893 					 */
894 					m_spare[nr_m_spare] = m;
895 					nr_m_spare++;
896 				}
897 #endif
898 				mpt += sizeof(struct mpc_intsrc);
899 				count += sizeof(struct mpc_intsrc);
900 				break;
901 			}
902 		case MP_LINTSRC:
903 			{
904 				struct mpc_lintsrc *m =
905 				    (struct mpc_lintsrc *)mpt;
906 				mpt += sizeof(*m);
907 				count += sizeof(*m);
908 				break;
909 			}
910 		default:
911 			/* wrong mptable */
912 			printk(KERN_ERR "Your mptable is wrong, contact your HW vendor!\n");
913 			printk(KERN_ERR "type %x\n", *mpt);
914 			print_hex_dump(KERN_ERR, "  ", DUMP_PREFIX_ADDRESS, 16,
915 					1, mpc, mpc->length, 1);
916 			goto out;
917 		}
918 	}
919 
920 #ifdef CONFIG_X86_IO_APIC
921 	for (i = 0; i < mp_irq_entries; i++) {
922 		if (irq_used[i])
923 			continue;
924 
925 		if (mp_irqs[i].mp_irqtype != mp_INT)
926 			continue;
927 
928 		if (mp_irqs[i].mp_irqflag != 0x0f)
929 			continue;
930 
931 		if (nr_m_spare > 0) {
932 			printk(KERN_INFO "*NEW* found ");
933 			nr_m_spare--;
934 			assign_to_mpc_intsrc(&mp_irqs[i], m_spare[nr_m_spare]);
935 			m_spare[nr_m_spare] = NULL;
936 		} else {
937 			struct mpc_intsrc *m = (struct mpc_intsrc *)mpt;
938 			count += sizeof(struct mpc_intsrc);
939 			if (!mpc_new_phys) {
940 				printk(KERN_INFO "No spare slots, try to append...take your risk, new mpc_length %x\n", count);
941 			} else {
942 				if (count <= mpc_new_length)
943 					printk(KERN_INFO "No spare slots, try to append..., new mpc_length %x\n", count);
944 				else {
945 					printk(KERN_ERR "mpc_new_length %lx is too small\n", mpc_new_length);
946 					goto out;
947 				}
948 			}
949 			assign_to_mpc_intsrc(&mp_irqs[i], m);
950 			mpc->length = count;
951 			mpt += sizeof(struct mpc_intsrc);
952 		}
953 		print_mp_irq_info(&mp_irqs[i]);
954 	}
955 #endif
956 out:
957 	/* update checksum */
958 	mpc->checksum = 0;
959 	mpc->checksum -= mpf_checksum((unsigned char *)mpc, mpc->length);
960 
961 	return 0;
962 }
963 
964 static int __initdata enable_update_mptable;
965 
966 static int __init update_mptable_setup(char *str)
967 {
968 	enable_update_mptable = 1;
969 	return 0;
970 }
971 early_param("update_mptable", update_mptable_setup);
972 
973 static unsigned long __initdata mpc_new_phys;
974 static unsigned long mpc_new_length __initdata = 4096;
975 
976 /* alloc_mptable or alloc_mptable=4k */
977 static int __initdata alloc_mptable;
978 static int __init parse_alloc_mptable_opt(char *p)
979 {
980 	enable_update_mptable = 1;
981 	alloc_mptable = 1;
982 	if (!p)
983 		return 0;
984 	mpc_new_length = memparse(p, &p);
985 	return 0;
986 }
987 early_param("alloc_mptable", parse_alloc_mptable_opt);
988 
989 void __init early_reserve_e820_mpc_new(void)
990 {
991 	if (enable_update_mptable && alloc_mptable) {
992 		u64 startt = 0;
993 #ifdef CONFIG_X86_TRAMPOLINE
994 		startt = TRAMPOLINE_BASE;
995 #endif
996 		mpc_new_phys = early_reserve_e820(startt, mpc_new_length, 4);
997 	}
998 }
999 
1000 static int __init update_mp_table(void)
1001 {
1002 	char str[16];
1003 	char oem[10];
1004 	struct intel_mp_floating *mpf;
1005 	struct mpc_table *mpc, *mpc_new;
1006 
1007 	if (!enable_update_mptable)
1008 		return 0;
1009 
1010 	mpf = mpf_found;
1011 	if (!mpf)
1012 		return 0;
1013 
1014 	/*
1015 	 * Now see if we need to go further.
1016 	 */
1017 	if (mpf->mpf_feature1 != 0)
1018 		return 0;
1019 
1020 	if (!mpf->mpf_physptr)
1021 		return 0;
1022 
1023 	mpc = phys_to_virt(mpf->mpf_physptr);
1024 
1025 	if (!smp_check_mpc(mpc, oem, str))
1026 		return 0;
1027 
1028 	printk(KERN_INFO "mpf: %lx\n", virt_to_phys(mpf));
1029 	printk(KERN_INFO "mpf_physptr: %x\n", mpf->mpf_physptr);
1030 
1031 	if (mpc_new_phys && mpc->length > mpc_new_length) {
1032 		mpc_new_phys = 0;
1033 		printk(KERN_INFO "mpc_new_length is %ld, please use alloc_mptable=8k\n",
1034 			 mpc_new_length);
1035 	}
1036 
1037 	if (!mpc_new_phys) {
1038 		unsigned char old, new;
1039 		/* check if we can change the postion */
1040 		mpc->checksum = 0;
1041 		old = mpf_checksum((unsigned char *)mpc, mpc->length);
1042 		mpc->checksum = 0xff;
1043 		new = mpf_checksum((unsigned char *)mpc, mpc->length);
1044 		if (old == new) {
1045 			printk(KERN_INFO "mpc is readonly, please try alloc_mptable instead\n");
1046 			return 0;
1047 		}
1048 		printk(KERN_INFO "use in-positon replacing\n");
1049 	} else {
1050 		mpf->mpf_physptr = mpc_new_phys;
1051 		mpc_new = phys_to_virt(mpc_new_phys);
1052 		memcpy(mpc_new, mpc, mpc->length);
1053 		mpc = mpc_new;
1054 		/* check if we can modify that */
1055 		if (mpc_new_phys - mpf->mpf_physptr) {
1056 			struct intel_mp_floating *mpf_new;
1057 			/* steal 16 bytes from [0, 1k) */
1058 			printk(KERN_INFO "mpf new: %x\n", 0x400 - 16);
1059 			mpf_new = phys_to_virt(0x400 - 16);
1060 			memcpy(mpf_new, mpf, 16);
1061 			mpf = mpf_new;
1062 			mpf->mpf_physptr = mpc_new_phys;
1063 		}
1064 		mpf->mpf_checksum = 0;
1065 		mpf->mpf_checksum -= mpf_checksum((unsigned char *)mpf, 16);
1066 		printk(KERN_INFO "mpf_physptr new: %x\n", mpf->mpf_physptr);
1067 	}
1068 
1069 	/*
1070 	 * only replace the one with mp_INT and
1071 	 *	 MP_IRQ_TRIGGER_LEVEL|MP_IRQ_POLARITY_LOW,
1072 	 * already in mp_irqs , stored by ... and mp_config_acpi_gsi,
1073 	 * may need pci=routeirq for all coverage
1074 	 */
1075 	replace_intsrc_all(mpc, mpc_new_phys, mpc_new_length);
1076 
1077 	return 0;
1078 }
1079 
1080 late_initcall(update_mp_table);
1081