xref: /openbmc/linux/arch/ia64/kernel/acpi.c (revision ba6e8564)
1 /*
2  *  acpi.c - Architecture-Specific Low-Level ACPI Support
3  *
4  *  Copyright (C) 1999 VA Linux Systems
5  *  Copyright (C) 1999,2000 Walt Drummond <drummond@valinux.com>
6  *  Copyright (C) 2000, 2002-2003 Hewlett-Packard Co.
7  *	David Mosberger-Tang <davidm@hpl.hp.com>
8  *  Copyright (C) 2000 Intel Corp.
9  *  Copyright (C) 2000,2001 J.I. Lee <jung-ik.lee@intel.com>
10  *  Copyright (C) 2001 Paul Diefenbaugh <paul.s.diefenbaugh@intel.com>
11  *  Copyright (C) 2001 Jenna Hall <jenna.s.hall@intel.com>
12  *  Copyright (C) 2001 Takayoshi Kochi <t-kochi@bq.jp.nec.com>
13  *  Copyright (C) 2002 Erich Focht <efocht@ess.nec.de>
14  *  Copyright (C) 2004 Ashok Raj <ashok.raj@intel.com>
15  *
16  * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
17  *
18  *  This program is free software; you can redistribute it and/or modify
19  *  it under the terms of the GNU General Public License as published by
20  *  the Free Software Foundation; either version 2 of the License, or
21  *  (at your option) any later version.
22  *
23  *  This program is distributed in the hope that it will be useful,
24  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
25  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
26  *  GNU General Public License for more details.
27  *
28  *  You should have received a copy of the GNU General Public License
29  *  along with this program; if not, write to the Free Software
30  *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
31  *
32  * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
33  */
34 
35 #include <linux/module.h>
36 #include <linux/init.h>
37 #include <linux/kernel.h>
38 #include <linux/sched.h>
39 #include <linux/smp.h>
40 #include <linux/string.h>
41 #include <linux/types.h>
42 #include <linux/irq.h>
43 #include <linux/acpi.h>
44 #include <linux/efi.h>
45 #include <linux/mmzone.h>
46 #include <linux/nodemask.h>
47 #include <asm/io.h>
48 #include <asm/iosapic.h>
49 #include <asm/machvec.h>
50 #include <asm/page.h>
51 #include <asm/system.h>
52 #include <asm/numa.h>
53 #include <asm/sal.h>
54 #include <asm/cyclone.h>
55 
56 #define BAD_MADT_ENTRY(entry, end) (                                        \
57 		(!entry) || (unsigned long)entry + sizeof(*entry) > end ||  \
58 		((struct acpi_subtable_header *)entry)->length < sizeof(*entry))
59 
60 #define PREFIX			"ACPI: "
61 
62 void (*pm_idle) (void);
63 EXPORT_SYMBOL(pm_idle);
64 void (*pm_power_off) (void);
65 EXPORT_SYMBOL(pm_power_off);
66 
67 unsigned int acpi_cpei_override;
68 unsigned int acpi_cpei_phys_cpuid;
69 
70 const char *acpi_get_sysname(void)
71 {
72 #ifdef CONFIG_IA64_GENERIC
73 	unsigned long rsdp_phys;
74 	struct acpi_table_rsdp *rsdp;
75 	struct acpi_table_xsdt *xsdt;
76 	struct acpi_table_header *hdr;
77 
78 	rsdp_phys = acpi_find_rsdp();
79 	if (!rsdp_phys) {
80 		printk(KERN_ERR
81 		       "ACPI 2.0 RSDP not found, default to \"dig\"\n");
82 		return "dig";
83 	}
84 
85 	rsdp = (struct acpi_table_rsdp *)__va(rsdp_phys);
86 	if (strncmp(rsdp->signature, ACPI_SIG_RSDP, sizeof(ACPI_SIG_RSDP) - 1)) {
87 		printk(KERN_ERR
88 		       "ACPI 2.0 RSDP signature incorrect, default to \"dig\"\n");
89 		return "dig";
90 	}
91 
92 	xsdt = (struct acpi_table_xsdt *)__va(rsdp->xsdt_physical_address);
93 	hdr = &xsdt->header;
94 	if (strncmp(hdr->signature, ACPI_SIG_XSDT, sizeof(ACPI_SIG_XSDT) - 1)) {
95 		printk(KERN_ERR
96 		       "ACPI 2.0 XSDT signature incorrect, default to \"dig\"\n");
97 		return "dig";
98 	}
99 
100 	if (!strcmp(hdr->oem_id, "HP")) {
101 		return "hpzx1";
102 	} else if (!strcmp(hdr->oem_id, "SGI")) {
103 		return "sn2";
104 	}
105 
106 	return "dig";
107 #else
108 # if defined (CONFIG_IA64_HP_SIM)
109 	return "hpsim";
110 # elif defined (CONFIG_IA64_HP_ZX1)
111 	return "hpzx1";
112 # elif defined (CONFIG_IA64_HP_ZX1_SWIOTLB)
113 	return "hpzx1_swiotlb";
114 # elif defined (CONFIG_IA64_SGI_SN2)
115 	return "sn2";
116 # elif defined (CONFIG_IA64_DIG)
117 	return "dig";
118 # else
119 #	error Unknown platform.  Fix acpi.c.
120 # endif
121 #endif
122 }
123 
124 #ifdef CONFIG_ACPI
125 
126 #define ACPI_MAX_PLATFORM_INTERRUPTS	256
127 
128 /* Array to record platform interrupt vectors for generic interrupt routing. */
129 int platform_intr_list[ACPI_MAX_PLATFORM_INTERRUPTS] = {
130 	[0 ... ACPI_MAX_PLATFORM_INTERRUPTS - 1] = -1
131 };
132 
133 enum acpi_irq_model_id acpi_irq_model = ACPI_IRQ_MODEL_IOSAPIC;
134 
135 /*
136  * Interrupt routing API for device drivers.  Provides interrupt vector for
137  * a generic platform event.  Currently only CPEI is implemented.
138  */
139 int acpi_request_vector(u32 int_type)
140 {
141 	int vector = -1;
142 
143 	if (int_type < ACPI_MAX_PLATFORM_INTERRUPTS) {
144 		/* corrected platform error interrupt */
145 		vector = platform_intr_list[int_type];
146 	} else
147 		printk(KERN_ERR
148 		       "acpi_request_vector(): invalid interrupt type\n");
149 	return vector;
150 }
151 
152 char *__acpi_map_table(unsigned long phys_addr, unsigned long size)
153 {
154 	return __va(phys_addr);
155 }
156 
157 /* --------------------------------------------------------------------------
158                             Boot-time Table Parsing
159    -------------------------------------------------------------------------- */
160 
161 static int total_cpus __initdata;
162 static int available_cpus __initdata;
163 struct acpi_table_madt *acpi_madt __initdata;
164 static u8 has_8259;
165 
166 static int __init
167 acpi_parse_lapic_addr_ovr(struct acpi_subtable_header * header,
168 			  const unsigned long end)
169 {
170 	struct acpi_madt_local_apic_override *lapic;
171 
172 	lapic = (struct acpi_madt_local_apic_override *)header;
173 
174 	if (BAD_MADT_ENTRY(lapic, end))
175 		return -EINVAL;
176 
177 	if (lapic->address) {
178 		iounmap(ipi_base_addr);
179 		ipi_base_addr = ioremap(lapic->address, 0);
180 	}
181 	return 0;
182 }
183 
184 static int __init
185 acpi_parse_lsapic(struct acpi_subtable_header * header, const unsigned long end)
186 {
187 	struct acpi_madt_local_sapic *lsapic;
188 
189 	lsapic = (struct acpi_madt_local_sapic *)header;
190 
191 	/*Skip BAD_MADT_ENTRY check, as lsapic size could vary */
192 
193 	if (lsapic->lapic_flags & ACPI_MADT_ENABLED) {
194 #ifdef CONFIG_SMP
195 		smp_boot_data.cpu_phys_id[available_cpus] =
196 		    (lsapic->id << 8) | lsapic->eid;
197 #endif
198 		++available_cpus;
199 	}
200 
201 	total_cpus++;
202 	return 0;
203 }
204 
205 static int __init
206 acpi_parse_lapic_nmi(struct acpi_subtable_header * header, const unsigned long end)
207 {
208 	struct acpi_madt_local_apic_nmi *lacpi_nmi;
209 
210 	lacpi_nmi = (struct acpi_madt_local_apic_nmi *)header;
211 
212 	if (BAD_MADT_ENTRY(lacpi_nmi, end))
213 		return -EINVAL;
214 
215 	/* TBD: Support lapic_nmi entries */
216 	return 0;
217 }
218 
219 static int __init
220 acpi_parse_iosapic(struct acpi_subtable_header * header, const unsigned long end)
221 {
222 	struct acpi_madt_io_sapic *iosapic;
223 
224 	iosapic = (struct acpi_madt_io_sapic *)header;
225 
226 	if (BAD_MADT_ENTRY(iosapic, end))
227 		return -EINVAL;
228 
229 	return iosapic_init(iosapic->address, iosapic->global_irq_base);
230 }
231 
232 static unsigned int __initdata acpi_madt_rev;
233 
234 static int __init
235 acpi_parse_plat_int_src(struct acpi_subtable_header * header,
236 			const unsigned long end)
237 {
238 	struct acpi_madt_interrupt_source *plintsrc;
239 	int vector;
240 
241 	plintsrc = (struct acpi_madt_interrupt_source *)header;
242 
243 	if (BAD_MADT_ENTRY(plintsrc, end))
244 		return -EINVAL;
245 
246 	/*
247 	 * Get vector assignment for this interrupt, set attributes,
248 	 * and program the IOSAPIC routing table.
249 	 */
250 	vector = iosapic_register_platform_intr(plintsrc->type,
251 						plintsrc->global_irq,
252 						plintsrc->io_sapic_vector,
253 						plintsrc->eid,
254 						plintsrc->id,
255 						((plintsrc->inti_flags & ACPI_MADT_POLARITY_MASK) ==
256 						 ACPI_MADT_POLARITY_ACTIVE_HIGH) ?
257 						IOSAPIC_POL_HIGH : IOSAPIC_POL_LOW,
258 						((plintsrc->inti_flags & ACPI_MADT_TRIGGER_MASK) ==
259 						 ACPI_MADT_TRIGGER_EDGE) ?
260 						IOSAPIC_EDGE : IOSAPIC_LEVEL);
261 
262 	platform_intr_list[plintsrc->type] = vector;
263 	if (acpi_madt_rev > 1) {
264 		acpi_cpei_override = plintsrc->flags & ACPI_MADT_CPEI_OVERRIDE;
265 	}
266 
267 	/*
268 	 * Save the physical id, so we can check when its being removed
269 	 */
270 	acpi_cpei_phys_cpuid = ((plintsrc->id << 8) | (plintsrc->eid)) & 0xffff;
271 
272 	return 0;
273 }
274 
275 #ifdef CONFIG_HOTPLUG_CPU
276 unsigned int can_cpei_retarget(void)
277 {
278 	extern int cpe_vector;
279 	extern unsigned int force_cpei_retarget;
280 
281 	/*
282 	 * Only if CPEI is supported and the override flag
283 	 * is present, otherwise return that its re-targettable
284 	 * if we are in polling mode.
285 	 */
286 	if (cpe_vector > 0) {
287 		if (acpi_cpei_override || force_cpei_retarget)
288 			return 1;
289 		else
290 			return 0;
291 	}
292 	return 1;
293 }
294 
295 unsigned int is_cpu_cpei_target(unsigned int cpu)
296 {
297 	unsigned int logical_id;
298 
299 	logical_id = cpu_logical_id(acpi_cpei_phys_cpuid);
300 
301 	if (logical_id == cpu)
302 		return 1;
303 	else
304 		return 0;
305 }
306 
307 void set_cpei_target_cpu(unsigned int cpu)
308 {
309 	acpi_cpei_phys_cpuid = cpu_physical_id(cpu);
310 }
311 #endif
312 
313 unsigned int get_cpei_target_cpu(void)
314 {
315 	return acpi_cpei_phys_cpuid;
316 }
317 
318 static int __init
319 acpi_parse_int_src_ovr(struct acpi_subtable_header * header,
320 		       const unsigned long end)
321 {
322 	struct acpi_madt_interrupt_override *p;
323 
324 	p = (struct acpi_madt_interrupt_override *)header;
325 
326 	if (BAD_MADT_ENTRY(p, end))
327 		return -EINVAL;
328 
329 	iosapic_override_isa_irq(p->source_irq, p->global_irq,
330 				 ((p->inti_flags & ACPI_MADT_POLARITY_MASK) ==
331 				  ACPI_MADT_POLARITY_ACTIVE_HIGH) ?
332 				 IOSAPIC_POL_HIGH : IOSAPIC_POL_LOW,
333 				 ((p->inti_flags & ACPI_MADT_TRIGGER_MASK) ==
334 				 ACPI_MADT_TRIGGER_EDGE) ?
335 				 IOSAPIC_EDGE : IOSAPIC_LEVEL);
336 	return 0;
337 }
338 
339 static int __init
340 acpi_parse_nmi_src(struct acpi_subtable_header * header, const unsigned long end)
341 {
342 	struct acpi_madt_nmi_source *nmi_src;
343 
344 	nmi_src = (struct acpi_madt_nmi_source *)header;
345 
346 	if (BAD_MADT_ENTRY(nmi_src, end))
347 		return -EINVAL;
348 
349 	/* TBD: Support nimsrc entries */
350 	return 0;
351 }
352 
353 static void __init acpi_madt_oem_check(char *oem_id, char *oem_table_id)
354 {
355 	if (!strncmp(oem_id, "IBM", 3) && (!strncmp(oem_table_id, "SERMOW", 6))) {
356 
357 		/*
358 		 * Unfortunately ITC_DRIFT is not yet part of the
359 		 * official SAL spec, so the ITC_DRIFT bit is not
360 		 * set by the BIOS on this hardware.
361 		 */
362 		sal_platform_features |= IA64_SAL_PLATFORM_FEATURE_ITC_DRIFT;
363 
364 		cyclone_setup();
365 	}
366 }
367 
368 static int __init acpi_parse_madt(struct acpi_table_header *table)
369 {
370 	if (!table)
371 		return -EINVAL;
372 
373 	acpi_madt = (struct acpi_table_madt *)table;
374 
375 	acpi_madt_rev = acpi_madt->header.revision;
376 
377 	/* remember the value for reference after free_initmem() */
378 #ifdef CONFIG_ITANIUM
379 	has_8259 = 1;		/* Firmware on old Itanium systems is broken */
380 #else
381 	has_8259 = acpi_madt->flags & ACPI_MADT_PCAT_COMPAT;
382 #endif
383 	iosapic_system_init(has_8259);
384 
385 	/* Get base address of IPI Message Block */
386 
387 	if (acpi_madt->address)
388 		ipi_base_addr = ioremap(acpi_madt->address, 0);
389 
390 	printk(KERN_INFO PREFIX "Local APIC address %p\n", ipi_base_addr);
391 
392 	acpi_madt_oem_check(acpi_madt->header.oem_id,
393 			    acpi_madt->header.oem_table_id);
394 
395 	return 0;
396 }
397 
398 #ifdef CONFIG_ACPI_NUMA
399 
400 #undef SLIT_DEBUG
401 
402 #define PXM_FLAG_LEN ((MAX_PXM_DOMAINS + 1)/32)
403 
404 static int __initdata srat_num_cpus;	/* number of cpus */
405 static u32 __devinitdata pxm_flag[PXM_FLAG_LEN];
406 #define pxm_bit_set(bit)	(set_bit(bit,(void *)pxm_flag))
407 #define pxm_bit_test(bit)	(test_bit(bit,(void *)pxm_flag))
408 static struct acpi_table_slit __initdata *slit_table;
409 
410 static int get_processor_proximity_domain(struct acpi_srat_cpu_affinity *pa)
411 {
412 	int pxm;
413 
414 	pxm = pa->proximity_domain_lo;
415 	if (ia64_platform_is("sn2"))
416 		pxm += pa->proximity_domain_hi[0] << 8;
417 	return pxm;
418 }
419 
420 static int get_memory_proximity_domain(struct acpi_srat_mem_affinity *ma)
421 {
422 	int pxm;
423 
424 	pxm = ma->proximity_domain;
425 	if (!ia64_platform_is("sn2"))
426 		pxm &= 0xff;
427 
428 	return pxm;
429 }
430 
431 /*
432  * ACPI 2.0 SLIT (System Locality Information Table)
433  * http://devresource.hp.com/devresource/Docs/TechPapers/IA64/slit.pdf
434  */
435 void __init acpi_numa_slit_init(struct acpi_table_slit *slit)
436 {
437 	u32 len;
438 
439 	len = sizeof(struct acpi_table_header) + 8
440 	    + slit->locality_count * slit->locality_count;
441 	if (slit->header.length != len) {
442 		printk(KERN_ERR
443 		       "ACPI 2.0 SLIT: size mismatch: %d expected, %d actual\n",
444 		       len, slit->header.length);
445 		memset(numa_slit, 10, sizeof(numa_slit));
446 		return;
447 	}
448 	slit_table = slit;
449 }
450 
451 void __init
452 acpi_numa_processor_affinity_init(struct acpi_srat_cpu_affinity *pa)
453 {
454 	int pxm;
455 
456 	if (!(pa->flags & ACPI_SRAT_CPU_ENABLED))
457 		return;
458 
459 	pxm = get_processor_proximity_domain(pa);
460 
461 	/* record this node in proximity bitmap */
462 	pxm_bit_set(pxm);
463 
464 	node_cpuid[srat_num_cpus].phys_id =
465 	    (pa->apic_id << 8) | (pa->local_sapic_eid);
466 	/* nid should be overridden as logical node id later */
467 	node_cpuid[srat_num_cpus].nid = pxm;
468 	srat_num_cpus++;
469 }
470 
471 void __init
472 acpi_numa_memory_affinity_init(struct acpi_srat_mem_affinity *ma)
473 {
474 	unsigned long paddr, size;
475 	int pxm;
476 	struct node_memblk_s *p, *q, *pend;
477 
478 	pxm = get_memory_proximity_domain(ma);
479 
480 	/* fill node memory chunk structure */
481 	paddr = ma->base_address;
482 	size = ma->length;
483 
484 	/* Ignore disabled entries */
485 	if (!(ma->flags & ACPI_SRAT_MEM_ENABLED))
486 		return;
487 
488 	/* record this node in proximity bitmap */
489 	pxm_bit_set(pxm);
490 
491 	/* Insertion sort based on base address */
492 	pend = &node_memblk[num_node_memblks];
493 	for (p = &node_memblk[0]; p < pend; p++) {
494 		if (paddr < p->start_paddr)
495 			break;
496 	}
497 	if (p < pend) {
498 		for (q = pend - 1; q >= p; q--)
499 			*(q + 1) = *q;
500 	}
501 	p->start_paddr = paddr;
502 	p->size = size;
503 	p->nid = pxm;
504 	num_node_memblks++;
505 }
506 
507 void __init acpi_numa_arch_fixup(void)
508 {
509 	int i, j, node_from, node_to;
510 
511 	/* If there's no SRAT, fix the phys_id and mark node 0 online */
512 	if (srat_num_cpus == 0) {
513 		node_set_online(0);
514 		node_cpuid[0].phys_id = hard_smp_processor_id();
515 		return;
516 	}
517 
518 	/*
519 	 * MCD - This can probably be dropped now.  No need for pxm ID to node ID
520 	 * mapping with sparse node numbering iff MAX_PXM_DOMAINS <= MAX_NUMNODES.
521 	 */
522 	nodes_clear(node_online_map);
523 	for (i = 0; i < MAX_PXM_DOMAINS; i++) {
524 		if (pxm_bit_test(i)) {
525 			int nid = acpi_map_pxm_to_node(i);
526 			node_set_online(nid);
527 		}
528 	}
529 
530 	/* set logical node id in memory chunk structure */
531 	for (i = 0; i < num_node_memblks; i++)
532 		node_memblk[i].nid = pxm_to_node(node_memblk[i].nid);
533 
534 	/* assign memory bank numbers for each chunk on each node */
535 	for_each_online_node(i) {
536 		int bank;
537 
538 		bank = 0;
539 		for (j = 0; j < num_node_memblks; j++)
540 			if (node_memblk[j].nid == i)
541 				node_memblk[j].bank = bank++;
542 	}
543 
544 	/* set logical node id in cpu structure */
545 	for (i = 0; i < srat_num_cpus; i++)
546 		node_cpuid[i].nid = pxm_to_node(node_cpuid[i].nid);
547 
548 	printk(KERN_INFO "Number of logical nodes in system = %d\n",
549 	       num_online_nodes());
550 	printk(KERN_INFO "Number of memory chunks in system = %d\n",
551 	       num_node_memblks);
552 
553 	if (!slit_table)
554 		return;
555 	memset(numa_slit, -1, sizeof(numa_slit));
556 	for (i = 0; i < slit_table->locality_count; i++) {
557 		if (!pxm_bit_test(i))
558 			continue;
559 		node_from = pxm_to_node(i);
560 		for (j = 0; j < slit_table->locality_count; j++) {
561 			if (!pxm_bit_test(j))
562 				continue;
563 			node_to = pxm_to_node(j);
564 			node_distance(node_from, node_to) =
565 			    slit_table->entry[i * slit_table->locality_count + j];
566 		}
567 	}
568 
569 #ifdef SLIT_DEBUG
570 	printk("ACPI 2.0 SLIT locality table:\n");
571 	for_each_online_node(i) {
572 		for_each_online_node(j)
573 		    printk("%03d ", node_distance(i, j));
574 		printk("\n");
575 	}
576 #endif
577 }
578 #endif				/* CONFIG_ACPI_NUMA */
579 
580 /*
581  * success: return IRQ number (>=0)
582  * failure: return < 0
583  */
584 int acpi_register_gsi(u32 gsi, int triggering, int polarity)
585 {
586 	if (acpi_irq_model == ACPI_IRQ_MODEL_PLATFORM)
587 		return gsi;
588 
589 	if (has_8259 && gsi < 16)
590 		return isa_irq_to_vector(gsi);
591 
592 	return iosapic_register_intr(gsi,
593 				     (polarity ==
594 				      ACPI_ACTIVE_HIGH) ? IOSAPIC_POL_HIGH :
595 				     IOSAPIC_POL_LOW,
596 				     (triggering ==
597 				      ACPI_EDGE_SENSITIVE) ? IOSAPIC_EDGE :
598 				     IOSAPIC_LEVEL);
599 }
600 
601 EXPORT_SYMBOL(acpi_register_gsi);
602 
603 void acpi_unregister_gsi(u32 gsi)
604 {
605 	if (acpi_irq_model == ACPI_IRQ_MODEL_PLATFORM)
606 		return;
607 
608 	iosapic_unregister_intr(gsi);
609 }
610 
611 EXPORT_SYMBOL(acpi_unregister_gsi);
612 
613 static int __init acpi_parse_fadt(struct acpi_table_header *table)
614 {
615 	struct acpi_table_header *fadt_header;
616 	struct acpi_table_fadt *fadt;
617 
618 	if (!table)
619 		return -EINVAL;
620 
621 	fadt_header = (struct acpi_table_header *)table;
622 	if (fadt_header->revision != 3)
623 		return -ENODEV;	/* Only deal with ACPI 2.0 FADT */
624 
625 	fadt = (struct acpi_table_fadt *)fadt_header;
626 
627 	acpi_register_gsi(fadt->sci_interrupt, ACPI_LEVEL_SENSITIVE, ACPI_ACTIVE_LOW);
628 	return 0;
629 }
630 
631 unsigned long __init acpi_find_rsdp(void)
632 {
633 	unsigned long rsdp_phys = 0;
634 
635 	if (efi.acpi20 != EFI_INVALID_TABLE_ADDR)
636 		rsdp_phys = efi.acpi20;
637 	else if (efi.acpi != EFI_INVALID_TABLE_ADDR)
638 		printk(KERN_WARNING PREFIX
639 		       "v1.0/r0.71 tables no longer supported\n");
640 	return rsdp_phys;
641 }
642 
643 int __init acpi_boot_init(void)
644 {
645 
646 	/*
647 	 * MADT
648 	 * ----
649 	 * Parse the Multiple APIC Description Table (MADT), if exists.
650 	 * Note that this table provides platform SMP configuration
651 	 * information -- the successor to MPS tables.
652 	 */
653 
654 	if (acpi_table_parse(ACPI_SIG_MADT, acpi_parse_madt)) {
655 		printk(KERN_ERR PREFIX "Can't find MADT\n");
656 		goto skip_madt;
657 	}
658 
659 	/* Local APIC */
660 
661 	if (acpi_table_parse_madt
662 	    (ACPI_MADT_TYPE_LOCAL_APIC_OVERRIDE, acpi_parse_lapic_addr_ovr, 0) < 0)
663 		printk(KERN_ERR PREFIX
664 		       "Error parsing LAPIC address override entry\n");
665 
666 	if (acpi_table_parse_madt(ACPI_MADT_TYPE_LOCAL_SAPIC, acpi_parse_lsapic, NR_CPUS)
667 	    < 1)
668 		printk(KERN_ERR PREFIX
669 		       "Error parsing MADT - no LAPIC entries\n");
670 
671 	if (acpi_table_parse_madt(ACPI_MADT_TYPE_LOCAL_APIC_NMI, acpi_parse_lapic_nmi, 0)
672 	    < 0)
673 		printk(KERN_ERR PREFIX "Error parsing LAPIC NMI entry\n");
674 
675 	/* I/O APIC */
676 
677 	if (acpi_table_parse_madt
678 	    (ACPI_MADT_TYPE_IO_SAPIC, acpi_parse_iosapic, NR_IOSAPICS) < 1)
679 		printk(KERN_ERR PREFIX
680 		       "Error parsing MADT - no IOSAPIC entries\n");
681 
682 	/* System-Level Interrupt Routing */
683 
684 	if (acpi_table_parse_madt
685 	    (ACPI_MADT_TYPE_INTERRUPT_SOURCE, acpi_parse_plat_int_src,
686 	     ACPI_MAX_PLATFORM_INTERRUPTS) < 0)
687 		printk(KERN_ERR PREFIX
688 		       "Error parsing platform interrupt source entry\n");
689 
690 	if (acpi_table_parse_madt
691 	    (ACPI_MADT_TYPE_INTERRUPT_OVERRIDE, acpi_parse_int_src_ovr, 0) < 0)
692 		printk(KERN_ERR PREFIX
693 		       "Error parsing interrupt source overrides entry\n");
694 
695 	if (acpi_table_parse_madt(ACPI_MADT_TYPE_NMI_SOURCE, acpi_parse_nmi_src, 0) < 0)
696 		printk(KERN_ERR PREFIX "Error parsing NMI SRC entry\n");
697       skip_madt:
698 
699 	/*
700 	 * FADT says whether a legacy keyboard controller is present.
701 	 * The FADT also contains an SCI_INT line, by which the system
702 	 * gets interrupts such as power and sleep buttons.  If it's not
703 	 * on a Legacy interrupt, it needs to be setup.
704 	 */
705 	if (acpi_table_parse(ACPI_SIG_FADT, acpi_parse_fadt))
706 		printk(KERN_ERR PREFIX "Can't find FADT\n");
707 
708 #ifdef CONFIG_SMP
709 	if (available_cpus == 0) {
710 		printk(KERN_INFO "ACPI: Found 0 CPUS; assuming 1\n");
711 		printk(KERN_INFO "CPU 0 (0x%04x)", hard_smp_processor_id());
712 		smp_boot_data.cpu_phys_id[available_cpus] =
713 		    hard_smp_processor_id();
714 		available_cpus = 1;	/* We've got at least one of these, no? */
715 	}
716 	smp_boot_data.cpu_count = available_cpus;
717 
718 	smp_build_cpu_map();
719 # ifdef CONFIG_ACPI_NUMA
720 	if (srat_num_cpus == 0) {
721 		int cpu, i = 1;
722 		for (cpu = 0; cpu < smp_boot_data.cpu_count; cpu++)
723 			if (smp_boot_data.cpu_phys_id[cpu] !=
724 			    hard_smp_processor_id())
725 				node_cpuid[i++].phys_id =
726 				    smp_boot_data.cpu_phys_id[cpu];
727 	}
728 # endif
729 #endif
730 #ifdef CONFIG_ACPI_NUMA
731 	build_cpu_to_node_map();
732 #endif
733 	/* Make boot-up look pretty */
734 	printk(KERN_INFO "%d CPUs available, %d CPUs total\n", available_cpus,
735 	       total_cpus);
736 	return 0;
737 }
738 
739 int acpi_gsi_to_irq(u32 gsi, unsigned int *irq)
740 {
741 	int vector;
742 
743 	if (has_8259 && gsi < 16)
744 		*irq = isa_irq_to_vector(gsi);
745 	else {
746 		vector = gsi_to_vector(gsi);
747 		if (vector == -1)
748 			return -1;
749 
750 		*irq = vector;
751 	}
752 	return 0;
753 }
754 
755 /*
756  *  ACPI based hotplug CPU support
757  */
758 #ifdef CONFIG_ACPI_HOTPLUG_CPU
759 static
760 int acpi_map_cpu2node(acpi_handle handle, int cpu, long physid)
761 {
762 #ifdef CONFIG_ACPI_NUMA
763 	int pxm_id;
764 	int nid;
765 
766 	pxm_id = acpi_get_pxm(handle);
767 	/*
768 	 * We don't have cpu-only-node hotadd. But if the system equips
769 	 * SRAT table, pxm is already found and node is ready.
770   	 * So, just pxm_to_nid(pxm) is OK.
771 	 * This code here is for the system which doesn't have full SRAT
772   	 * table for possible cpus.
773 	 */
774 	nid = acpi_map_pxm_to_node(pxm_id);
775 	node_cpuid[cpu].phys_id = physid;
776 	node_cpuid[cpu].nid = nid;
777 #endif
778 	return (0);
779 }
780 
781 int additional_cpus __initdata = -1;
782 
783 static __init int setup_additional_cpus(char *s)
784 {
785 	if (s)
786 		additional_cpus = simple_strtol(s, NULL, 0);
787 
788 	return 0;
789 }
790 
791 early_param("additional_cpus", setup_additional_cpus);
792 
793 /*
794  * cpu_possible_map should be static, it cannot change as cpu's
795  * are onlined, or offlined. The reason is per-cpu data-structures
796  * are allocated by some modules at init time, and dont expect to
797  * do this dynamically on cpu arrival/departure.
798  * cpu_present_map on the other hand can change dynamically.
799  * In case when cpu_hotplug is not compiled, then we resort to current
800  * behaviour, which is cpu_possible == cpu_present.
801  * - Ashok Raj
802  *
803  * Three ways to find out the number of additional hotplug CPUs:
804  * - If the BIOS specified disabled CPUs in ACPI/mptables use that.
805  * - The user can overwrite it with additional_cpus=NUM
806  * - Otherwise don't reserve additional CPUs.
807  */
808 __init void prefill_possible_map(void)
809 {
810 	int i;
811 	int possible, disabled_cpus;
812 
813 	disabled_cpus = total_cpus - available_cpus;
814 
815  	if (additional_cpus == -1) {
816  		if (disabled_cpus > 0)
817 			additional_cpus = disabled_cpus;
818  		else
819 			additional_cpus = 0;
820  	}
821 
822 	possible = available_cpus + additional_cpus;
823 
824 	if (possible > NR_CPUS)
825 		possible = NR_CPUS;
826 
827 	printk(KERN_INFO "SMP: Allowing %d CPUs, %d hotplug CPUs\n",
828 		possible, max((possible - available_cpus), 0));
829 
830 	for (i = 0; i < possible; i++)
831 		cpu_set(i, cpu_possible_map);
832 }
833 
834 int acpi_map_lsapic(acpi_handle handle, int *pcpu)
835 {
836 	struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
837 	union acpi_object *obj;
838 	struct acpi_madt_local_sapic *lsapic;
839 	cpumask_t tmp_map;
840 	long physid;
841 	int cpu;
842 
843 	if (ACPI_FAILURE(acpi_evaluate_object(handle, "_MAT", NULL, &buffer)))
844 		return -EINVAL;
845 
846 	if (!buffer.length || !buffer.pointer)
847 		return -EINVAL;
848 
849 	obj = buffer.pointer;
850 	if (obj->type != ACPI_TYPE_BUFFER)
851 	{
852 		kfree(buffer.pointer);
853 		return -EINVAL;
854 	}
855 
856 	lsapic = (struct acpi_madt_local_sapic *)obj->buffer.pointer;
857 
858 	if ((lsapic->header.type != ACPI_MADT_TYPE_LOCAL_SAPIC) ||
859 	    (!lsapic->lapic_flags & ACPI_MADT_ENABLED)) {
860 		kfree(buffer.pointer);
861 		return -EINVAL;
862 	}
863 
864 	physid = ((lsapic->id << 8) | (lsapic->eid));
865 
866 	kfree(buffer.pointer);
867 	buffer.length = ACPI_ALLOCATE_BUFFER;
868 	buffer.pointer = NULL;
869 
870 	cpus_complement(tmp_map, cpu_present_map);
871 	cpu = first_cpu(tmp_map);
872 	if (cpu >= NR_CPUS)
873 		return -EINVAL;
874 
875 	acpi_map_cpu2node(handle, cpu, physid);
876 
877 	cpu_set(cpu, cpu_present_map);
878 	ia64_cpu_to_sapicid[cpu] = physid;
879 
880 	*pcpu = cpu;
881 	return (0);
882 }
883 
884 EXPORT_SYMBOL(acpi_map_lsapic);
885 
886 int acpi_unmap_lsapic(int cpu)
887 {
888 	ia64_cpu_to_sapicid[cpu] = -1;
889 	cpu_clear(cpu, cpu_present_map);
890 
891 #ifdef CONFIG_ACPI_NUMA
892 	/* NUMA specific cleanup's */
893 #endif
894 
895 	return (0);
896 }
897 
898 EXPORT_SYMBOL(acpi_unmap_lsapic);
899 #endif				/* CONFIG_ACPI_HOTPLUG_CPU */
900 
901 #ifdef CONFIG_ACPI_NUMA
902 static acpi_status __devinit
903 acpi_map_iosapic(acpi_handle handle, u32 depth, void *context, void **ret)
904 {
905 	struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
906 	union acpi_object *obj;
907 	struct acpi_madt_io_sapic *iosapic;
908 	unsigned int gsi_base;
909 	int pxm, node;
910 
911 	/* Only care about objects w/ a method that returns the MADT */
912 	if (ACPI_FAILURE(acpi_evaluate_object(handle, "_MAT", NULL, &buffer)))
913 		return AE_OK;
914 
915 	if (!buffer.length || !buffer.pointer)
916 		return AE_OK;
917 
918 	obj = buffer.pointer;
919 	if (obj->type != ACPI_TYPE_BUFFER ||
920 	    obj->buffer.length < sizeof(*iosapic)) {
921 		kfree(buffer.pointer);
922 		return AE_OK;
923 	}
924 
925 	iosapic = (struct acpi_madt_io_sapic *)obj->buffer.pointer;
926 
927 	if (iosapic->header.type != ACPI_MADT_TYPE_IO_SAPIC) {
928 		kfree(buffer.pointer);
929 		return AE_OK;
930 	}
931 
932 	gsi_base = iosapic->global_irq_base;
933 
934 	kfree(buffer.pointer);
935 
936 	/*
937 	 * OK, it's an IOSAPIC MADT entry, look for a _PXM value to tell
938 	 * us which node to associate this with.
939 	 */
940 	pxm = acpi_get_pxm(handle);
941 	if (pxm < 0)
942 		return AE_OK;
943 
944 	node = pxm_to_node(pxm);
945 
946 	if (node >= MAX_NUMNODES || !node_online(node) ||
947 	    cpus_empty(node_to_cpumask(node)))
948 		return AE_OK;
949 
950 	/* We know a gsi to node mapping! */
951 	map_iosapic_to_node(gsi_base, node);
952 	return AE_OK;
953 }
954 
955 static int __init
956 acpi_map_iosapics (void)
957 {
958 	acpi_get_devices(NULL, acpi_map_iosapic, NULL, NULL);
959 	return 0;
960 }
961 
962 fs_initcall(acpi_map_iosapics);
963 #endif				/* CONFIG_ACPI_NUMA */
964 
965 int acpi_register_ioapic(acpi_handle handle, u64 phys_addr, u32 gsi_base)
966 {
967 	int err;
968 
969 	if ((err = iosapic_init(phys_addr, gsi_base)))
970 		return err;
971 
972 #ifdef CONFIG_ACPI_NUMA
973 	acpi_map_iosapic(handle, 0, NULL, NULL);
974 #endif				/* CONFIG_ACPI_NUMA */
975 
976 	return 0;
977 }
978 
979 EXPORT_SYMBOL(acpi_register_ioapic);
980 
981 int acpi_unregister_ioapic(acpi_handle handle, u32 gsi_base)
982 {
983 	return iosapic_remove(gsi_base);
984 }
985 
986 EXPORT_SYMBOL(acpi_unregister_ioapic);
987 
988 #endif				/* CONFIG_ACPI */
989