xref: /openbmc/linux/arch/x86/kernel/mpparse.c (revision 8fa5723aa7e053d498336b48448b292fc2e0458b)
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@redhat.com>
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 
20 #include <asm/smp.h>
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/acpi.h>
27 #include <asm/bios_ebda.h>
28 #include <asm/e820.h>
29 #include <asm/trampoline.h>
30 #include <asm/setup.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_config_processor *m)
53 {
54 	int apicid;
55 	char *bootup_cpu = "";
56 
57 	if (!(m->mpc_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->mpc_apicid;
66 
67 	if (m->mpc_cpuflag & CPU_BOOTPROCESSOR) {
68 		bootup_cpu = " (Bootup-CPU)";
69 		boot_cpu_physical_apicid = m->mpc_apicid;
70 	}
71 
72 	printk(KERN_INFO "Processor #%d%s\n", m->mpc_apicid, bootup_cpu);
73 	generic_processor_info(apicid, m->mpc_apicver);
74 }
75 
76 #ifdef CONFIG_X86_IO_APIC
77 static void __init MP_bus_info(struct mpc_config_bus *m)
78 {
79 	char str[7];
80 	memcpy(str, m->mpc_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->mpc_busid, str);
87 
88 #if MAX_MP_BUSSES < 256
89 	if (m->mpc_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->mpc_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->mpc_busid, mp_bus_not_pci);
99 #if defined(CONFIG_EISA) || defined (CONFIG_MCA)
100 		mp_bus_id_to_type[m->mpc_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->mpc_busid, mp_bus_not_pci);
107 #if defined(CONFIG_EISA) || defined (CONFIG_MCA)
108 		mp_bus_id_to_type[m->mpc_busid] = MP_BUS_PCI;
109 	} else if (strncmp(str, BUSTYPE_EISA, sizeof(BUSTYPE_EISA) - 1) == 0) {
110 		mp_bus_id_to_type[m->mpc_busid] = MP_BUS_EISA;
111 	} else if (strncmp(str, BUSTYPE_MCA, sizeof(BUSTYPE_MCA) - 1) == 0) {
112 		mp_bus_id_to_type[m->mpc_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_config_ioapic *m)
137 {
138 	if (!(m->mpc_flags & MPC_APIC_USABLE))
139 		return;
140 
141 	printk(KERN_INFO "I/O APIC #%d Version %d at 0x%X.\n",
142 	       m->mpc_apicid, m->mpc_apicver, m->mpc_apicaddr);
143 
144 	if (bad_ioapic(m->mpc_apicaddr))
145 		return;
146 
147 	mp_ioapics[nr_ioapics].mp_apicaddr = m->mpc_apicaddr;
148 	mp_ioapics[nr_ioapics].mp_apicid = m->mpc_apicid;
149 	mp_ioapics[nr_ioapics].mp_type = m->mpc_type;
150 	mp_ioapics[nr_ioapics].mp_apicver = m->mpc_apicver;
151 	mp_ioapics[nr_ioapics].mp_flags = m->mpc_flags;
152 	nr_ioapics++;
153 }
154 
155 static void print_MP_intsrc_info(struct mpc_config_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->mpc_irqtype, m->mpc_irqflag & 3,
160 		(m->mpc_irqflag >> 2) & 3, m->mpc_srcbus,
161 		m->mpc_srcbusirq, m->mpc_dstapic, m->mpc_dstirq);
162 }
163 
164 static void __init print_mp_irq_info(struct mp_config_intsrc *mp_irq)
165 {
166 	apic_printk(APIC_VERBOSE, "Int: type %d, pol %d, trig %d, bus %02x,"
167 		" IRQ %02x, APIC ID %x, APIC INT %02x\n",
168 		mp_irq->mp_irqtype, mp_irq->mp_irqflag & 3,
169 		(mp_irq->mp_irqflag >> 2) & 3, mp_irq->mp_srcbus,
170 		mp_irq->mp_srcbusirq, mp_irq->mp_dstapic, mp_irq->mp_dstirq);
171 }
172 
173 static void __init assign_to_mp_irq(struct mpc_config_intsrc *m,
174 				    struct mp_config_intsrc *mp_irq)
175 {
176 	mp_irq->mp_dstapic = m->mpc_dstapic;
177 	mp_irq->mp_type = m->mpc_type;
178 	mp_irq->mp_irqtype = m->mpc_irqtype;
179 	mp_irq->mp_irqflag = m->mpc_irqflag;
180 	mp_irq->mp_srcbus = m->mpc_srcbus;
181 	mp_irq->mp_srcbusirq = m->mpc_srcbusirq;
182 	mp_irq->mp_dstirq = m->mpc_dstirq;
183 }
184 
185 static void __init assign_to_mpc_intsrc(struct mp_config_intsrc *mp_irq,
186 					struct mpc_config_intsrc *m)
187 {
188 	m->mpc_dstapic = mp_irq->mp_dstapic;
189 	m->mpc_type = mp_irq->mp_type;
190 	m->mpc_irqtype = mp_irq->mp_irqtype;
191 	m->mpc_irqflag = mp_irq->mp_irqflag;
192 	m->mpc_srcbus = mp_irq->mp_srcbus;
193 	m->mpc_srcbusirq = mp_irq->mp_srcbusirq;
194 	m->mpc_dstirq = mp_irq->mp_dstirq;
195 }
196 
197 static int __init mp_irq_mpc_intsrc_cmp(struct mp_config_intsrc *mp_irq,
198 					struct mpc_config_intsrc *m)
199 {
200 	if (mp_irq->mp_dstapic != m->mpc_dstapic)
201 		return 1;
202 	if (mp_irq->mp_type != m->mpc_type)
203 		return 2;
204 	if (mp_irq->mp_irqtype != m->mpc_irqtype)
205 		return 3;
206 	if (mp_irq->mp_irqflag != m->mpc_irqflag)
207 		return 4;
208 	if (mp_irq->mp_srcbus != m->mpc_srcbus)
209 		return 5;
210 	if (mp_irq->mp_srcbusirq != m->mpc_srcbusirq)
211 		return 6;
212 	if (mp_irq->mp_dstirq != m->mpc_dstirq)
213 		return 7;
214 
215 	return 0;
216 }
217 
218 static void __init MP_intsrc_info(struct mpc_config_intsrc *m)
219 {
220 	int i;
221 
222 	print_MP_intsrc_info(m);
223 
224 	for (i = 0; i < mp_irq_entries; i++) {
225 		if (!mp_irq_mpc_intsrc_cmp(&mp_irqs[i], m))
226 			return;
227 	}
228 
229 	assign_to_mp_irq(m, &mp_irqs[mp_irq_entries]);
230 	if (++mp_irq_entries == MAX_IRQ_SOURCES)
231 		panic("Max # of irq sources exceeded!!\n");
232 }
233 
234 #endif
235 
236 static void __init MP_lintsrc_info(struct mpc_config_lintsrc *m)
237 {
238 	apic_printk(APIC_VERBOSE, "Lint: type %d, pol %d, trig %d, bus %02x,"
239 		" IRQ %02x, APIC ID %x, APIC LINT %02x\n",
240 		m->mpc_irqtype, m->mpc_irqflag & 3,
241 		(m->mpc_irqflag >> 2) & 3, m->mpc_srcbusid,
242 		m->mpc_srcbusirq, m->mpc_destapic, m->mpc_destapiclint);
243 }
244 
245 /*
246  * Read/parse the MPC
247  */
248 
249 static int __init smp_check_mpc(struct mp_config_table *mpc, char *oem,
250 				char *str)
251 {
252 
253 	if (memcmp(mpc->mpc_signature, MPC_SIGNATURE, 4)) {
254 		printk(KERN_ERR "MPTABLE: bad signature [%c%c%c%c]!\n",
255 		       mpc->mpc_signature[0], mpc->mpc_signature[1],
256 		       mpc->mpc_signature[2], mpc->mpc_signature[3]);
257 		return 0;
258 	}
259 	if (mpf_checksum((unsigned char *)mpc, mpc->mpc_length)) {
260 		printk(KERN_ERR "MPTABLE: checksum error!\n");
261 		return 0;
262 	}
263 	if (mpc->mpc_spec != 0x01 && mpc->mpc_spec != 0x04) {
264 		printk(KERN_ERR "MPTABLE: bad table version (%d)!!\n",
265 		       mpc->mpc_spec);
266 		return 0;
267 	}
268 	if (!mpc->mpc_lapic) {
269 		printk(KERN_ERR "MPTABLE: null local APIC address!\n");
270 		return 0;
271 	}
272 	memcpy(oem, mpc->mpc_oem, 8);
273 	oem[8] = 0;
274 	printk(KERN_INFO "MPTABLE: OEM ID: %s\n", oem);
275 
276 	memcpy(str, mpc->mpc_productid, 12);
277 	str[12] = 0;
278 
279 	printk(KERN_INFO "MPTABLE: Product ID: %s\n", str);
280 
281 	printk(KERN_INFO "MPTABLE: APIC at: 0x%X\n", mpc->mpc_lapic);
282 
283 	return 1;
284 }
285 
286 static int __init smp_read_mpc(struct mp_config_table *mpc, unsigned early)
287 {
288 	char str[16];
289 	char oem[10];
290 
291 	int count = sizeof(*mpc);
292 	unsigned char *mpt = ((unsigned char *)mpc) + count;
293 
294 	if (!smp_check_mpc(mpc, oem, str))
295 		return 0;
296 
297 #ifdef CONFIG_X86_32
298 	/*
299 	 * need to make sure summit and es7000's mps_oem_check is safe to be
300 	 * called early via genericarch 's mps_oem_check
301 	 */
302 	if (early) {
303 #ifdef CONFIG_X86_NUMAQ
304 		numaq_mps_oem_check(mpc, oem, str);
305 #endif
306 	} else
307 		mps_oem_check(mpc, oem, str);
308 #endif
309 	/* save the local APIC address, it might be non-default */
310 	if (!acpi_lapic)
311 		mp_lapic_addr = mpc->mpc_lapic;
312 
313 	if (early)
314 		return 1;
315 
316 	if (mpc->mpc_oemptr && x86_quirks->smp_read_mpc_oem) {
317 		struct mp_config_oemtable *oem_table = (struct mp_config_oemtable *)(unsigned long)mpc->mpc_oemptr;
318 		x86_quirks->smp_read_mpc_oem(oem_table, mpc->mpc_oemsize);
319 	}
320 
321 	/*
322 	 *      Now process the configuration blocks.
323 	 */
324 	if (x86_quirks->mpc_record)
325 		*x86_quirks->mpc_record = 0;
326 
327 	while (count < mpc->mpc_length) {
328 		switch (*mpt) {
329 		case MP_PROCESSOR:
330 			{
331 				struct mpc_config_processor *m =
332 				    (struct mpc_config_processor *)mpt;
333 				/* ACPI may have already provided this data */
334 				if (!acpi_lapic)
335 					MP_processor_info(m);
336 				mpt += sizeof(*m);
337 				count += sizeof(*m);
338 				break;
339 			}
340 		case MP_BUS:
341 			{
342 				struct mpc_config_bus *m =
343 				    (struct mpc_config_bus *)mpt;
344 #ifdef CONFIG_X86_IO_APIC
345 				MP_bus_info(m);
346 #endif
347 				mpt += sizeof(*m);
348 				count += sizeof(*m);
349 				break;
350 			}
351 		case MP_IOAPIC:
352 			{
353 #ifdef CONFIG_X86_IO_APIC
354 				struct mpc_config_ioapic *m =
355 				    (struct mpc_config_ioapic *)mpt;
356 				MP_ioapic_info(m);
357 #endif
358 				mpt += sizeof(struct mpc_config_ioapic);
359 				count += sizeof(struct mpc_config_ioapic);
360 				break;
361 			}
362 		case MP_INTSRC:
363 			{
364 #ifdef CONFIG_X86_IO_APIC
365 				struct mpc_config_intsrc *m =
366 				    (struct mpc_config_intsrc *)mpt;
367 
368 				MP_intsrc_info(m);
369 #endif
370 				mpt += sizeof(struct mpc_config_intsrc);
371 				count += sizeof(struct mpc_config_intsrc);
372 				break;
373 			}
374 		case MP_LINTSRC:
375 			{
376 				struct mpc_config_lintsrc *m =
377 				    (struct mpc_config_lintsrc *)mpt;
378 				MP_lintsrc_info(m);
379 				mpt += sizeof(*m);
380 				count += sizeof(*m);
381 				break;
382 			}
383 		default:
384 			/* wrong mptable */
385 			printk(KERN_ERR "Your mptable is wrong, contact your HW vendor!\n");
386 			printk(KERN_ERR "type %x\n", *mpt);
387 			print_hex_dump(KERN_ERR, "  ", DUMP_PREFIX_ADDRESS, 16,
388 					1, mpc, mpc->mpc_length, 1);
389 			count = mpc->mpc_length;
390 			break;
391 		}
392 		if (x86_quirks->mpc_record)
393 			(*x86_quirks->mpc_record)++;
394 	}
395 
396 #ifdef CONFIG_X86_GENERICARCH
397        generic_bigsmp_probe();
398 #endif
399 
400 #ifdef CONFIG_X86_32
401 	setup_apic_routing();
402 #endif
403 	if (!num_processors)
404 		printk(KERN_ERR "MPTABLE: no processors registered!\n");
405 	return num_processors;
406 }
407 
408 #ifdef CONFIG_X86_IO_APIC
409 
410 static int __init ELCR_trigger(unsigned int irq)
411 {
412 	unsigned int port;
413 
414 	port = 0x4d0 + (irq >> 3);
415 	return (inb(port) >> (irq & 7)) & 1;
416 }
417 
418 static void __init construct_default_ioirq_mptable(int mpc_default_type)
419 {
420 	struct mpc_config_intsrc intsrc;
421 	int i;
422 	int ELCR_fallback = 0;
423 
424 	intsrc.mpc_type = MP_INTSRC;
425 	intsrc.mpc_irqflag = 0;	/* conforming */
426 	intsrc.mpc_srcbus = 0;
427 	intsrc.mpc_dstapic = mp_ioapics[0].mp_apicid;
428 
429 	intsrc.mpc_irqtype = mp_INT;
430 
431 	/*
432 	 *  If true, we have an ISA/PCI system with no IRQ entries
433 	 *  in the MP table. To prevent the PCI interrupts from being set up
434 	 *  incorrectly, we try to use the ELCR. The sanity check to see if
435 	 *  there is good ELCR data is very simple - IRQ0, 1, 2 and 13 can
436 	 *  never be level sensitive, so we simply see if the ELCR agrees.
437 	 *  If it does, we assume it's valid.
438 	 */
439 	if (mpc_default_type == 5) {
440 		printk(KERN_INFO "ISA/PCI bus type with no IRQ information... "
441 		       "falling back to ELCR\n");
442 
443 		if (ELCR_trigger(0) || ELCR_trigger(1) || ELCR_trigger(2) ||
444 		    ELCR_trigger(13))
445 			printk(KERN_ERR "ELCR contains invalid data... "
446 			       "not using ELCR\n");
447 		else {
448 			printk(KERN_INFO
449 			       "Using ELCR to identify PCI interrupts\n");
450 			ELCR_fallback = 1;
451 		}
452 	}
453 
454 	for (i = 0; i < 16; i++) {
455 		switch (mpc_default_type) {
456 		case 2:
457 			if (i == 0 || i == 13)
458 				continue;	/* IRQ0 & IRQ13 not connected */
459 			/* fall through */
460 		default:
461 			if (i == 2)
462 				continue;	/* IRQ2 is never connected */
463 		}
464 
465 		if (ELCR_fallback) {
466 			/*
467 			 *  If the ELCR indicates a level-sensitive interrupt, we
468 			 *  copy that information over to the MP table in the
469 			 *  irqflag field (level sensitive, active high polarity).
470 			 */
471 			if (ELCR_trigger(i))
472 				intsrc.mpc_irqflag = 13;
473 			else
474 				intsrc.mpc_irqflag = 0;
475 		}
476 
477 		intsrc.mpc_srcbusirq = i;
478 		intsrc.mpc_dstirq = i ? i : 2;	/* IRQ0 to INTIN2 */
479 		MP_intsrc_info(&intsrc);
480 	}
481 
482 	intsrc.mpc_irqtype = mp_ExtINT;
483 	intsrc.mpc_srcbusirq = 0;
484 	intsrc.mpc_dstirq = 0;	/* 8259A to INTIN0 */
485 	MP_intsrc_info(&intsrc);
486 }
487 
488 
489 static void __init construct_ioapic_table(int mpc_default_type)
490 {
491 	struct mpc_config_ioapic ioapic;
492 	struct mpc_config_bus bus;
493 
494 	bus.mpc_type = MP_BUS;
495 	bus.mpc_busid = 0;
496 	switch (mpc_default_type) {
497 	default:
498 		printk(KERN_ERR "???\nUnknown standard configuration %d\n",
499 		       mpc_default_type);
500 		/* fall through */
501 	case 1:
502 	case 5:
503 		memcpy(bus.mpc_bustype, "ISA   ", 6);
504 		break;
505 	case 2:
506 	case 6:
507 	case 3:
508 		memcpy(bus.mpc_bustype, "EISA  ", 6);
509 		break;
510 	case 4:
511 	case 7:
512 		memcpy(bus.mpc_bustype, "MCA   ", 6);
513 	}
514 	MP_bus_info(&bus);
515 	if (mpc_default_type > 4) {
516 		bus.mpc_busid = 1;
517 		memcpy(bus.mpc_bustype, "PCI   ", 6);
518 		MP_bus_info(&bus);
519 	}
520 
521 	ioapic.mpc_type = MP_IOAPIC;
522 	ioapic.mpc_apicid = 2;
523 	ioapic.mpc_apicver = mpc_default_type > 4 ? 0x10 : 0x01;
524 	ioapic.mpc_flags = MPC_APIC_USABLE;
525 	ioapic.mpc_apicaddr = 0xFEC00000;
526 	MP_ioapic_info(&ioapic);
527 
528 	/*
529 	 * We set up most of the low 16 IO-APIC pins according to MPS rules.
530 	 */
531 	construct_default_ioirq_mptable(mpc_default_type);
532 }
533 #else
534 static inline void __init construct_ioapic_table(int mpc_default_type) { }
535 #endif
536 
537 static inline void __init construct_default_ISA_mptable(int mpc_default_type)
538 {
539 	struct mpc_config_processor processor;
540 	struct mpc_config_lintsrc lintsrc;
541 	int linttypes[2] = { mp_ExtINT, mp_NMI };
542 	int i;
543 
544 	/*
545 	 * local APIC has default address
546 	 */
547 	mp_lapic_addr = APIC_DEFAULT_PHYS_BASE;
548 
549 	/*
550 	 * 2 CPUs, numbered 0 & 1.
551 	 */
552 	processor.mpc_type = MP_PROCESSOR;
553 	/* Either an integrated APIC or a discrete 82489DX. */
554 	processor.mpc_apicver = mpc_default_type > 4 ? 0x10 : 0x01;
555 	processor.mpc_cpuflag = CPU_ENABLED;
556 	processor.mpc_cpufeature = (boot_cpu_data.x86 << 8) |
557 	    (boot_cpu_data.x86_model << 4) | boot_cpu_data.x86_mask;
558 	processor.mpc_featureflag = boot_cpu_data.x86_capability[0];
559 	processor.mpc_reserved[0] = 0;
560 	processor.mpc_reserved[1] = 0;
561 	for (i = 0; i < 2; i++) {
562 		processor.mpc_apicid = i;
563 		MP_processor_info(&processor);
564 	}
565 
566 	construct_ioapic_table(mpc_default_type);
567 
568 	lintsrc.mpc_type = MP_LINTSRC;
569 	lintsrc.mpc_irqflag = 0;	/* conforming */
570 	lintsrc.mpc_srcbusid = 0;
571 	lintsrc.mpc_srcbusirq = 0;
572 	lintsrc.mpc_destapic = MP_APIC_ALL;
573 	for (i = 0; i < 2; i++) {
574 		lintsrc.mpc_irqtype = linttypes[i];
575 		lintsrc.mpc_destapiclint = i;
576 		MP_lintsrc_info(&lintsrc);
577 	}
578 }
579 
580 static struct intel_mp_floating *mpf_found;
581 
582 /*
583  * Scan the memory blocks for an SMP configuration block.
584  */
585 static void __init __get_smp_config(unsigned int early)
586 {
587 	struct intel_mp_floating *mpf = mpf_found;
588 
589 	if (x86_quirks->mach_get_smp_config) {
590 		if (x86_quirks->mach_get_smp_config(early))
591 			return;
592 	}
593 	if (acpi_lapic && early)
594 		return;
595 	/*
596 	 * ACPI supports both logical (e.g. Hyper-Threading) and physical
597 	 * processors, where MPS only supports physical.
598 	 */
599 	if (acpi_lapic && acpi_ioapic) {
600 		printk(KERN_INFO "Using ACPI (MADT) for SMP configuration "
601 		       "information\n");
602 		return;
603 	} else if (acpi_lapic)
604 		printk(KERN_INFO "Using ACPI for processor (LAPIC) "
605 		       "configuration information\n");
606 
607 	printk(KERN_INFO "Intel MultiProcessor Specification v1.%d\n",
608 	       mpf->mpf_specification);
609 #if defined(CONFIG_X86_LOCAL_APIC) && defined(CONFIG_X86_32)
610 	if (mpf->mpf_feature2 & (1 << 7)) {
611 		printk(KERN_INFO "    IMCR and PIC compatibility mode.\n");
612 		pic_mode = 1;
613 	} else {
614 		printk(KERN_INFO "    Virtual Wire compatibility mode.\n");
615 		pic_mode = 0;
616 	}
617 #endif
618 	/*
619 	 * Now see if we need to read further.
620 	 */
621 	if (mpf->mpf_feature1 != 0) {
622 		if (early) {
623 			/*
624 			 * local APIC has default address
625 			 */
626 			mp_lapic_addr = APIC_DEFAULT_PHYS_BASE;
627 			return;
628 		}
629 
630 		printk(KERN_INFO "Default MP configuration #%d\n",
631 		       mpf->mpf_feature1);
632 		construct_default_ISA_mptable(mpf->mpf_feature1);
633 
634 	} else if (mpf->mpf_physptr) {
635 
636 		/*
637 		 * Read the physical hardware table.  Anything here will
638 		 * override the defaults.
639 		 */
640 		if (!smp_read_mpc(phys_to_virt(mpf->mpf_physptr), early)) {
641 #ifdef CONFIG_X86_LOCAL_APIC
642 			smp_found_config = 0;
643 #endif
644 			printk(KERN_ERR
645 			       "BIOS bug, MP table errors detected!...\n");
646 			printk(KERN_ERR "... disabling SMP support. "
647 			       "(tell your hw vendor)\n");
648 			return;
649 		}
650 
651 		if (early)
652 			return;
653 #ifdef CONFIG_X86_IO_APIC
654 		/*
655 		 * If there are no explicit MP IRQ entries, then we are
656 		 * broken.  We set up most of the low 16 IO-APIC pins to
657 		 * ISA defaults and hope it will work.
658 		 */
659 		if (!mp_irq_entries) {
660 			struct mpc_config_bus bus;
661 
662 			printk(KERN_ERR "BIOS bug, no explicit IRQ entries, "
663 			       "using default mptable. "
664 			       "(tell your hw vendor)\n");
665 
666 			bus.mpc_type = MP_BUS;
667 			bus.mpc_busid = 0;
668 			memcpy(bus.mpc_bustype, "ISA   ", 6);
669 			MP_bus_info(&bus);
670 
671 			construct_default_ioirq_mptable(0);
672 		}
673 #endif
674 	} else
675 		BUG();
676 
677 	if (!early)
678 		printk(KERN_INFO "Processors: %d\n", num_processors);
679 	/*
680 	 * Only use the first configuration found.
681 	 */
682 }
683 
684 void __init early_get_smp_config(void)
685 {
686 	__get_smp_config(1);
687 }
688 
689 void __init get_smp_config(void)
690 {
691 	__get_smp_config(0);
692 }
693 
694 static int __init smp_scan_config(unsigned long base, unsigned long length,
695 				  unsigned reserve)
696 {
697 	unsigned int *bp = phys_to_virt(base);
698 	struct intel_mp_floating *mpf;
699 
700 	apic_printk(APIC_VERBOSE, "Scan SMP from %p for %ld bytes.\n",
701 			bp, length);
702 	BUILD_BUG_ON(sizeof(*mpf) != 16);
703 
704 	while (length > 0) {
705 		mpf = (struct intel_mp_floating *)bp;
706 		if ((*bp == SMP_MAGIC_IDENT) &&
707 		    (mpf->mpf_length == 1) &&
708 		    !mpf_checksum((unsigned char *)bp, 16) &&
709 		    ((mpf->mpf_specification == 1)
710 		     || (mpf->mpf_specification == 4))) {
711 #ifdef CONFIG_X86_LOCAL_APIC
712 			smp_found_config = 1;
713 #endif
714 			mpf_found = mpf;
715 
716 			printk(KERN_INFO "found SMP MP-table at [%p] %08lx\n",
717 			       mpf, virt_to_phys(mpf));
718 
719 			if (!reserve)
720 				return 1;
721 			reserve_bootmem_generic(virt_to_phys(mpf), PAGE_SIZE,
722 					BOOTMEM_DEFAULT);
723 			if (mpf->mpf_physptr) {
724 				unsigned long size = PAGE_SIZE;
725 #ifdef CONFIG_X86_32
726 				/*
727 				 * We cannot access to MPC table to compute
728 				 * table size yet, as only few megabytes from
729 				 * the bottom is mapped now.
730 				 * PC-9800's MPC table places on the very last
731 				 * of physical memory; so that simply reserving
732 				 * PAGE_SIZE from mpg->mpf_physptr yields BUG()
733 				 * in reserve_bootmem.
734 				 */
735 				unsigned long end = max_low_pfn * PAGE_SIZE;
736 				if (mpf->mpf_physptr + size > end)
737 					size = end - mpf->mpf_physptr;
738 #endif
739 				reserve_bootmem_generic(mpf->mpf_physptr, size,
740 						BOOTMEM_DEFAULT);
741 			}
742 
743 			return 1;
744 		}
745 		bp += 4;
746 		length -= 16;
747 	}
748 	return 0;
749 }
750 
751 static void __init __find_smp_config(unsigned int reserve)
752 {
753 	unsigned int address;
754 
755 	if (x86_quirks->mach_find_smp_config) {
756 		if (x86_quirks->mach_find_smp_config(reserve))
757 			return;
758 	}
759 	/*
760 	 * FIXME: Linux assumes you have 640K of base ram..
761 	 * this continues the error...
762 	 *
763 	 * 1) Scan the bottom 1K for a signature
764 	 * 2) Scan the top 1K of base RAM
765 	 * 3) Scan the 64K of bios
766 	 */
767 	if (smp_scan_config(0x0, 0x400, reserve) ||
768 	    smp_scan_config(639 * 0x400, 0x400, reserve) ||
769 	    smp_scan_config(0xF0000, 0x10000, reserve))
770 		return;
771 	/*
772 	 * If it is an SMP machine we should know now, unless the
773 	 * configuration is in an EISA/MCA bus machine with an
774 	 * extended bios data area.
775 	 *
776 	 * there is a real-mode segmented pointer pointing to the
777 	 * 4K EBDA area at 0x40E, calculate and scan it here.
778 	 *
779 	 * NOTE! There are Linux loaders that will corrupt the EBDA
780 	 * area, and as such this kind of SMP config may be less
781 	 * trustworthy, simply because the SMP table may have been
782 	 * stomped on during early boot. These loaders are buggy and
783 	 * should be fixed.
784 	 *
785 	 * MP1.4 SPEC states to only scan first 1K of 4K EBDA.
786 	 */
787 
788 	address = get_bios_ebda();
789 	if (address)
790 		smp_scan_config(address, 0x400, reserve);
791 }
792 
793 void __init early_find_smp_config(void)
794 {
795 	__find_smp_config(0);
796 }
797 
798 void __init find_smp_config(void)
799 {
800 	__find_smp_config(1);
801 }
802 
803 #ifdef CONFIG_X86_IO_APIC
804 static u8 __initdata irq_used[MAX_IRQ_SOURCES];
805 
806 static int  __init get_MP_intsrc_index(struct mpc_config_intsrc *m)
807 {
808 	int i;
809 
810 	if (m->mpc_irqtype != mp_INT)
811 		return 0;
812 
813 	if (m->mpc_irqflag != 0x0f)
814 		return 0;
815 
816 	/* not legacy */
817 
818 	for (i = 0; i < mp_irq_entries; i++) {
819 		if (mp_irqs[i].mp_irqtype != mp_INT)
820 			continue;
821 
822 		if (mp_irqs[i].mp_irqflag != 0x0f)
823 			continue;
824 
825 		if (mp_irqs[i].mp_srcbus != m->mpc_srcbus)
826 			continue;
827 		if (mp_irqs[i].mp_srcbusirq != m->mpc_srcbusirq)
828 			continue;
829 		if (irq_used[i]) {
830 			/* already claimed */
831 			return -2;
832 		}
833 		irq_used[i] = 1;
834 		return i;
835 	}
836 
837 	/* not found */
838 	return -1;
839 }
840 
841 #define SPARE_SLOT_NUM 20
842 
843 static struct mpc_config_intsrc __initdata *m_spare[SPARE_SLOT_NUM];
844 #endif
845 
846 static int  __init replace_intsrc_all(struct mp_config_table *mpc,
847 					unsigned long mpc_new_phys,
848 					unsigned long mpc_new_length)
849 {
850 #ifdef CONFIG_X86_IO_APIC
851 	int i;
852 	int nr_m_spare = 0;
853 #endif
854 
855 	int count = sizeof(*mpc);
856 	unsigned char *mpt = ((unsigned char *)mpc) + count;
857 
858 	printk(KERN_INFO "mpc_length %x\n", mpc->mpc_length);
859 	while (count < mpc->mpc_length) {
860 		switch (*mpt) {
861 		case MP_PROCESSOR:
862 			{
863 				struct mpc_config_processor *m =
864 				    (struct mpc_config_processor *)mpt;
865 				mpt += sizeof(*m);
866 				count += sizeof(*m);
867 				break;
868 			}
869 		case MP_BUS:
870 			{
871 				struct mpc_config_bus *m =
872 				    (struct mpc_config_bus *)mpt;
873 				mpt += sizeof(*m);
874 				count += sizeof(*m);
875 				break;
876 			}
877 		case MP_IOAPIC:
878 			{
879 				mpt += sizeof(struct mpc_config_ioapic);
880 				count += sizeof(struct mpc_config_ioapic);
881 				break;
882 			}
883 		case MP_INTSRC:
884 			{
885 #ifdef CONFIG_X86_IO_APIC
886 				struct mpc_config_intsrc *m =
887 				    (struct mpc_config_intsrc *)mpt;
888 
889 				printk(KERN_INFO "OLD ");
890 				print_MP_intsrc_info(m);
891 				i = get_MP_intsrc_index(m);
892 				if (i > 0) {
893 					assign_to_mpc_intsrc(&mp_irqs[i], m);
894 					printk(KERN_INFO "NEW ");
895 					print_mp_irq_info(&mp_irqs[i]);
896 				} else if (!i) {
897 					/* legacy, do nothing */
898 				} else if (nr_m_spare < SPARE_SLOT_NUM) {
899 					/*
900 					 * not found (-1), or duplicated (-2)
901 					 * are invalid entries,
902 					 * we need to use the slot  later
903 					 */
904 					m_spare[nr_m_spare] = m;
905 					nr_m_spare++;
906 				}
907 #endif
908 				mpt += sizeof(struct mpc_config_intsrc);
909 				count += sizeof(struct mpc_config_intsrc);
910 				break;
911 			}
912 		case MP_LINTSRC:
913 			{
914 				struct mpc_config_lintsrc *m =
915 				    (struct mpc_config_lintsrc *)mpt;
916 				mpt += sizeof(*m);
917 				count += sizeof(*m);
918 				break;
919 			}
920 		default:
921 			/* wrong mptable */
922 			printk(KERN_ERR "Your mptable is wrong, contact your HW vendor!\n");
923 			printk(KERN_ERR "type %x\n", *mpt);
924 			print_hex_dump(KERN_ERR, "  ", DUMP_PREFIX_ADDRESS, 16,
925 					1, mpc, mpc->mpc_length, 1);
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].mp_irqtype != mp_INT)
936 			continue;
937 
938 		if (mp_irqs[i].mp_irqflag != 0x0f)
939 			continue;
940 
941 		if (nr_m_spare > 0) {
942 			printk(KERN_INFO "*NEW* found ");
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_config_intsrc *m =
948 			    (struct mpc_config_intsrc *)mpt;
949 			count += sizeof(struct mpc_config_intsrc);
950 			if (!mpc_new_phys) {
951 				printk(KERN_INFO "No spare slots, try to append...take your risk, new mpc_length %x\n", count);
952 			} else {
953 				if (count <= mpc_new_length)
954 					printk(KERN_INFO "No spare slots, try to append..., new mpc_length %x\n", count);
955 				else {
956 					printk(KERN_ERR "mpc_new_length %lx is too small\n", mpc_new_length);
957 					goto out;
958 				}
959 			}
960 			assign_to_mpc_intsrc(&mp_irqs[i], m);
961 			mpc->mpc_length = count;
962 			mpt += sizeof(struct mpc_config_intsrc);
963 		}
964 		print_mp_irq_info(&mp_irqs[i]);
965 	}
966 #endif
967 out:
968 	/* update checksum */
969 	mpc->mpc_checksum = 0;
970 	mpc->mpc_checksum -= mpf_checksum((unsigned char *)mpc,
971 					   mpc->mpc_length);
972 
973 	return 0;
974 }
975 
976 static int __initdata enable_update_mptable;
977 
978 static int __init update_mptable_setup(char *str)
979 {
980 	enable_update_mptable = 1;
981 	return 0;
982 }
983 early_param("update_mptable", update_mptable_setup);
984 
985 static unsigned long __initdata mpc_new_phys;
986 static unsigned long mpc_new_length __initdata = 4096;
987 
988 /* alloc_mptable or alloc_mptable=4k */
989 static int __initdata alloc_mptable;
990 static int __init parse_alloc_mptable_opt(char *p)
991 {
992 	enable_update_mptable = 1;
993 	alloc_mptable = 1;
994 	if (!p)
995 		return 0;
996 	mpc_new_length = memparse(p, &p);
997 	return 0;
998 }
999 early_param("alloc_mptable", parse_alloc_mptable_opt);
1000 
1001 void __init early_reserve_e820_mpc_new(void)
1002 {
1003 	if (enable_update_mptable && alloc_mptable) {
1004 		u64 startt = 0;
1005 #ifdef CONFIG_X86_TRAMPOLINE
1006 		startt = TRAMPOLINE_BASE;
1007 #endif
1008 		mpc_new_phys = early_reserve_e820(startt, mpc_new_length, 4);
1009 	}
1010 }
1011 
1012 static int __init update_mp_table(void)
1013 {
1014 	char str[16];
1015 	char oem[10];
1016 	struct intel_mp_floating *mpf;
1017 	struct mp_config_table *mpc;
1018 	struct mp_config_table *mpc_new;
1019 
1020 	if (!enable_update_mptable)
1021 		return 0;
1022 
1023 	mpf = mpf_found;
1024 	if (!mpf)
1025 		return 0;
1026 
1027 	/*
1028 	 * Now see if we need to go further.
1029 	 */
1030 	if (mpf->mpf_feature1 != 0)
1031 		return 0;
1032 
1033 	if (!mpf->mpf_physptr)
1034 		return 0;
1035 
1036 	mpc = phys_to_virt(mpf->mpf_physptr);
1037 
1038 	if (!smp_check_mpc(mpc, oem, str))
1039 		return 0;
1040 
1041 	printk(KERN_INFO "mpf: %lx\n", virt_to_phys(mpf));
1042 	printk(KERN_INFO "mpf_physptr: %x\n", mpf->mpf_physptr);
1043 
1044 	if (mpc_new_phys && mpc->mpc_length > mpc_new_length) {
1045 		mpc_new_phys = 0;
1046 		printk(KERN_INFO "mpc_new_length is %ld, please use alloc_mptable=8k\n",
1047 			 mpc_new_length);
1048 	}
1049 
1050 	if (!mpc_new_phys) {
1051 		unsigned char old, new;
1052 		/* check if we can change the postion */
1053 		mpc->mpc_checksum = 0;
1054 		old = mpf_checksum((unsigned char *)mpc, mpc->mpc_length);
1055 		mpc->mpc_checksum = 0xff;
1056 		new = mpf_checksum((unsigned char *)mpc, mpc->mpc_length);
1057 		if (old == new) {
1058 			printk(KERN_INFO "mpc is readonly, please try alloc_mptable instead\n");
1059 			return 0;
1060 		}
1061 		printk(KERN_INFO "use in-positon replacing\n");
1062 	} else {
1063 		mpf->mpf_physptr = mpc_new_phys;
1064 		mpc_new = phys_to_virt(mpc_new_phys);
1065 		memcpy(mpc_new, mpc, mpc->mpc_length);
1066 		mpc = mpc_new;
1067 		/* check if we can modify that */
1068 		if (mpc_new_phys - mpf->mpf_physptr) {
1069 			struct intel_mp_floating *mpf_new;
1070 			/* steal 16 bytes from [0, 1k) */
1071 			printk(KERN_INFO "mpf new: %x\n", 0x400 - 16);
1072 			mpf_new = phys_to_virt(0x400 - 16);
1073 			memcpy(mpf_new, mpf, 16);
1074 			mpf = mpf_new;
1075 			mpf->mpf_physptr = mpc_new_phys;
1076 		}
1077 		mpf->mpf_checksum = 0;
1078 		mpf->mpf_checksum -= mpf_checksum((unsigned char *)mpf, 16);
1079 		printk(KERN_INFO "mpf_physptr new: %x\n", mpf->mpf_physptr);
1080 	}
1081 
1082 	/*
1083 	 * only replace the one with mp_INT and
1084 	 *	 MP_IRQ_TRIGGER_LEVEL|MP_IRQ_POLARITY_LOW,
1085 	 * already in mp_irqs , stored by ... and mp_config_acpi_gsi,
1086 	 * may need pci=routeirq for all coverage
1087 	 */
1088 	replace_intsrc_all(mpc, mpc_new_phys, mpc_new_length);
1089 
1090 	return 0;
1091 }
1092 
1093 late_initcall(update_mp_table);
1094