xref: /linux/arch/x86/kernel/acpi/boot.c (revision c4101e55974cc7d835fbd2d8e01553a3f61e9e75)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  *  boot.c - Architecture-Specific Low-Level ACPI Boot Support
4  *
5  *  Copyright (C) 2001, 2002 Paul Diefenbaugh <paul.s.diefenbaugh@intel.com>
6  *  Copyright (C) 2001 Jun Nakajima <jun.nakajima@intel.com>
7  */
8 #define pr_fmt(fmt) "ACPI: " fmt
9 
10 #include <linux/init.h>
11 #include <linux/acpi.h>
12 #include <linux/acpi_pmtmr.h>
13 #include <linux/efi.h>
14 #include <linux/cpumask.h>
15 #include <linux/export.h>
16 #include <linux/dmi.h>
17 #include <linux/irq.h>
18 #include <linux/slab.h>
19 #include <linux/memblock.h>
20 #include <linux/ioport.h>
21 #include <linux/pci.h>
22 #include <linux/efi-bgrt.h>
23 #include <linux/serial_core.h>
24 #include <linux/pgtable.h>
25 
26 #include <asm/e820/api.h>
27 #include <asm/irqdomain.h>
28 #include <asm/pci_x86.h>
29 #include <asm/io_apic.h>
30 #include <asm/apic.h>
31 #include <asm/io.h>
32 #include <asm/mpspec.h>
33 #include <asm/smp.h>
34 #include <asm/i8259.h>
35 #include <asm/setup.h>
36 
37 #include "sleep.h" /* To include x86_acpi_suspend_lowlevel */
38 static int __initdata acpi_force = 0;
39 int acpi_disabled;
40 EXPORT_SYMBOL(acpi_disabled);
41 
42 #ifdef	CONFIG_X86_64
43 # include <asm/proto.h>
44 #endif				/* X86 */
45 
46 int acpi_noirq;				/* skip ACPI IRQ initialization */
47 static int acpi_nobgrt;			/* skip ACPI BGRT */
48 int acpi_pci_disabled;		/* skip ACPI PCI scan and IRQ initialization */
49 EXPORT_SYMBOL(acpi_pci_disabled);
50 
51 int acpi_lapic;
52 int acpi_ioapic;
53 int acpi_strict;
54 int acpi_disable_cmcff;
55 bool acpi_int_src_ovr[NR_IRQS_LEGACY];
56 
57 /* ACPI SCI override configuration */
58 u8 acpi_sci_flags __initdata;
59 u32 acpi_sci_override_gsi __initdata = INVALID_ACPI_IRQ;
60 int acpi_skip_timer_override __initdata;
61 int acpi_use_timer_override __initdata;
62 int acpi_fix_pin2_polarity __initdata;
63 
64 #ifdef CONFIG_X86_LOCAL_APIC
65 static u64 acpi_lapic_addr __initdata = APIC_DEFAULT_PHYS_BASE;
66 static bool has_lapic_cpus __initdata;
67 static bool acpi_support_online_capable;
68 #endif
69 
70 #ifdef CONFIG_X86_64
71 /* Physical address of the Multiprocessor Wakeup Structure mailbox */
72 static u64 acpi_mp_wake_mailbox_paddr;
73 /* Virtual address of the Multiprocessor Wakeup Structure mailbox */
74 static struct acpi_madt_multiproc_wakeup_mailbox *acpi_mp_wake_mailbox;
75 #endif
76 
77 #ifdef CONFIG_X86_IO_APIC
78 /*
79  * Locks related to IOAPIC hotplug
80  * Hotplug side:
81  *	->device_hotplug_lock
82  *		->acpi_ioapic_lock
83  *			->ioapic_lock
84  * Interrupt mapping side:
85  *	->acpi_ioapic_lock
86  *		->ioapic_mutex
87  *			->ioapic_lock
88  */
89 static DEFINE_MUTEX(acpi_ioapic_lock);
90 #endif
91 
92 /* --------------------------------------------------------------------------
93                               Boot-time Configuration
94    -------------------------------------------------------------------------- */
95 
96 /*
97  * The default interrupt routing model is PIC (8259).  This gets
98  * overridden if IOAPICs are enumerated (below).
99  */
100 enum acpi_irq_model_id acpi_irq_model = ACPI_IRQ_MODEL_PIC;
101 
102 
103 /*
104  * ISA irqs by default are the first 16 gsis but can be
105  * any gsi as specified by an interrupt source override.
106  */
107 static u32 isa_irq_to_gsi[NR_IRQS_LEGACY] __read_mostly = {
108 	0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15
109 };
110 
111 /*
112  * This is just a simple wrapper around early_memremap(),
113  * with sanity checks for phys == 0 and size == 0.
114  */
115 void __init __iomem *__acpi_map_table(unsigned long phys, unsigned long size)
116 {
117 
118 	if (!phys || !size)
119 		return NULL;
120 
121 	return early_memremap(phys, size);
122 }
123 
124 void __init __acpi_unmap_table(void __iomem *map, unsigned long size)
125 {
126 	if (!map || !size)
127 		return;
128 
129 	early_memunmap(map, size);
130 }
131 
132 #ifdef CONFIG_X86_LOCAL_APIC
133 static int __init acpi_parse_madt(struct acpi_table_header *table)
134 {
135 	struct acpi_table_madt *madt = NULL;
136 
137 	if (!boot_cpu_has(X86_FEATURE_APIC))
138 		return -EINVAL;
139 
140 	madt = (struct acpi_table_madt *)table;
141 	if (!madt) {
142 		pr_warn("Unable to map MADT\n");
143 		return -ENODEV;
144 	}
145 
146 	if (madt->address) {
147 		acpi_lapic_addr = (u64) madt->address;
148 
149 		pr_debug("Local APIC address 0x%08x\n", madt->address);
150 	}
151 
152 	if (madt->flags & ACPI_MADT_PCAT_COMPAT)
153 		legacy_pic_pcat_compat();
154 
155 	/* ACPI 6.3 and newer support the online capable bit. */
156 	if (acpi_gbl_FADT.header.revision > 6 ||
157 	    (acpi_gbl_FADT.header.revision == 6 &&
158 	     acpi_gbl_FADT.minor_revision >= 3))
159 		acpi_support_online_capable = true;
160 
161 	default_acpi_madt_oem_check(madt->header.oem_id,
162 				    madt->header.oem_table_id);
163 
164 	return 0;
165 }
166 
167 /**
168  * acpi_register_lapic - register a local apic and generates a logic cpu number
169  * @id: local apic id to register
170  * @acpiid: ACPI id to register
171  * @enabled: this cpu is enabled or not
172  *
173  * Returns the logic cpu number which maps to the local apic
174  */
175 static int acpi_register_lapic(int id, u32 acpiid, u8 enabled)
176 {
177 	int cpu;
178 
179 	if (id >= MAX_LOCAL_APIC) {
180 		pr_info("skipped apicid that is too big\n");
181 		return -EINVAL;
182 	}
183 
184 	if (!enabled) {
185 		++disabled_cpus;
186 		return -EINVAL;
187 	}
188 
189 	cpu = generic_processor_info(id);
190 	if (cpu >= 0)
191 		early_per_cpu(x86_cpu_to_acpiid, cpu) = acpiid;
192 
193 	return cpu;
194 }
195 
196 static bool __init acpi_is_processor_usable(u32 lapic_flags)
197 {
198 	if (lapic_flags & ACPI_MADT_ENABLED)
199 		return true;
200 
201 	if (!acpi_support_online_capable ||
202 	    (lapic_flags & ACPI_MADT_ONLINE_CAPABLE))
203 		return true;
204 
205 	return false;
206 }
207 
208 static int __init
209 acpi_parse_x2apic(union acpi_subtable_headers *header, const unsigned long end)
210 {
211 	struct acpi_madt_local_x2apic *processor = NULL;
212 #ifdef CONFIG_X86_X2APIC
213 	u32 apic_id;
214 	u8 enabled;
215 #endif
216 
217 	processor = (struct acpi_madt_local_x2apic *)header;
218 
219 	if (BAD_MADT_ENTRY(processor, end))
220 		return -EINVAL;
221 
222 	acpi_table_print_madt_entry(&header->common);
223 
224 #ifdef CONFIG_X86_X2APIC
225 	apic_id = processor->local_apic_id;
226 	enabled = processor->lapic_flags & ACPI_MADT_ENABLED;
227 
228 	/* Ignore invalid ID */
229 	if (apic_id == 0xffffffff)
230 		return 0;
231 
232 	/* don't register processors that cannot be onlined */
233 	if (!acpi_is_processor_usable(processor->lapic_flags))
234 		return 0;
235 
236 	/*
237 	 * According to https://uefi.org/specs/ACPI/6.5/05_ACPI_Software_Programming_Model.html#processor-local-x2apic-structure
238 	 * when MADT provides both valid LAPIC and x2APIC entries, the APIC ID
239 	 * in x2APIC must be equal or greater than 0xff.
240 	 */
241 	if (has_lapic_cpus && apic_id < 0xff)
242 		return 0;
243 
244 	/*
245 	 * We need to register disabled CPU as well to permit
246 	 * counting disabled CPUs. This allows us to size
247 	 * cpus_possible_map more accurately, to permit
248 	 * to not preallocating memory for all NR_CPUS
249 	 * when we use CPU hotplug.
250 	 */
251 	if (!apic_id_valid(apic_id)) {
252 		if (enabled)
253 			pr_warn("x2apic entry ignored\n");
254 		return 0;
255 	}
256 
257 	acpi_register_lapic(apic_id, processor->uid, enabled);
258 #else
259 	pr_warn("x2apic entry ignored\n");
260 #endif
261 
262 	return 0;
263 }
264 
265 static int __init
266 acpi_parse_lapic(union acpi_subtable_headers * header, const unsigned long end)
267 {
268 	struct acpi_madt_local_apic *processor = NULL;
269 
270 	processor = (struct acpi_madt_local_apic *)header;
271 
272 	if (BAD_MADT_ENTRY(processor, end))
273 		return -EINVAL;
274 
275 	acpi_table_print_madt_entry(&header->common);
276 
277 	/* Ignore invalid ID */
278 	if (processor->id == 0xff)
279 		return 0;
280 
281 	/* don't register processors that can not be onlined */
282 	if (!acpi_is_processor_usable(processor->lapic_flags))
283 		return 0;
284 
285 	/*
286 	 * We need to register disabled CPU as well to permit
287 	 * counting disabled CPUs. This allows us to size
288 	 * cpus_possible_map more accurately, to permit
289 	 * to not preallocating memory for all NR_CPUS
290 	 * when we use CPU hotplug.
291 	 */
292 	acpi_register_lapic(processor->id,	/* APIC ID */
293 			    processor->processor_id, /* ACPI ID */
294 			    processor->lapic_flags & ACPI_MADT_ENABLED);
295 
296 	has_lapic_cpus = true;
297 	return 0;
298 }
299 
300 static int __init
301 acpi_parse_sapic(union acpi_subtable_headers *header, const unsigned long end)
302 {
303 	struct acpi_madt_local_sapic *processor = NULL;
304 
305 	processor = (struct acpi_madt_local_sapic *)header;
306 
307 	if (BAD_MADT_ENTRY(processor, end))
308 		return -EINVAL;
309 
310 	acpi_table_print_madt_entry(&header->common);
311 
312 	acpi_register_lapic((processor->id << 8) | processor->eid,/* APIC ID */
313 			    processor->processor_id, /* ACPI ID */
314 			    processor->lapic_flags & ACPI_MADT_ENABLED);
315 
316 	return 0;
317 }
318 
319 static int __init
320 acpi_parse_lapic_addr_ovr(union acpi_subtable_headers * header,
321 			  const unsigned long end)
322 {
323 	struct acpi_madt_local_apic_override *lapic_addr_ovr = NULL;
324 
325 	lapic_addr_ovr = (struct acpi_madt_local_apic_override *)header;
326 
327 	if (BAD_MADT_ENTRY(lapic_addr_ovr, end))
328 		return -EINVAL;
329 
330 	acpi_table_print_madt_entry(&header->common);
331 
332 	acpi_lapic_addr = lapic_addr_ovr->address;
333 
334 	return 0;
335 }
336 
337 static int __init
338 acpi_parse_x2apic_nmi(union acpi_subtable_headers *header,
339 		      const unsigned long end)
340 {
341 	struct acpi_madt_local_x2apic_nmi *x2apic_nmi = NULL;
342 
343 	x2apic_nmi = (struct acpi_madt_local_x2apic_nmi *)header;
344 
345 	if (BAD_MADT_ENTRY(x2apic_nmi, end))
346 		return -EINVAL;
347 
348 	acpi_table_print_madt_entry(&header->common);
349 
350 	if (x2apic_nmi->lint != 1)
351 		pr_warn("NMI not connected to LINT 1!\n");
352 
353 	return 0;
354 }
355 
356 static int __init
357 acpi_parse_lapic_nmi(union acpi_subtable_headers * header, const unsigned long end)
358 {
359 	struct acpi_madt_local_apic_nmi *lapic_nmi = NULL;
360 
361 	lapic_nmi = (struct acpi_madt_local_apic_nmi *)header;
362 
363 	if (BAD_MADT_ENTRY(lapic_nmi, end))
364 		return -EINVAL;
365 
366 	acpi_table_print_madt_entry(&header->common);
367 
368 	if (lapic_nmi->lint != 1)
369 		pr_warn("NMI not connected to LINT 1!\n");
370 
371 	return 0;
372 }
373 
374 #ifdef CONFIG_X86_64
375 static int acpi_wakeup_cpu(u32 apicid, unsigned long start_ip)
376 {
377 	/*
378 	 * Remap mailbox memory only for the first call to acpi_wakeup_cpu().
379 	 *
380 	 * Wakeup of secondary CPUs is fully serialized in the core code.
381 	 * No need to protect acpi_mp_wake_mailbox from concurrent accesses.
382 	 */
383 	if (!acpi_mp_wake_mailbox) {
384 		acpi_mp_wake_mailbox = memremap(acpi_mp_wake_mailbox_paddr,
385 						sizeof(*acpi_mp_wake_mailbox),
386 						MEMREMAP_WB);
387 	}
388 
389 	/*
390 	 * Mailbox memory is shared between the firmware and OS. Firmware will
391 	 * listen on mailbox command address, and once it receives the wakeup
392 	 * command, the CPU associated with the given apicid will be booted.
393 	 *
394 	 * The value of 'apic_id' and 'wakeup_vector' must be visible to the
395 	 * firmware before the wakeup command is visible.  smp_store_release()
396 	 * ensures ordering and visibility.
397 	 */
398 	acpi_mp_wake_mailbox->apic_id	    = apicid;
399 	acpi_mp_wake_mailbox->wakeup_vector = start_ip;
400 	smp_store_release(&acpi_mp_wake_mailbox->command,
401 			  ACPI_MP_WAKE_COMMAND_WAKEUP);
402 
403 	/*
404 	 * Wait for the CPU to wake up.
405 	 *
406 	 * The CPU being woken up is essentially in a spin loop waiting to be
407 	 * woken up. It should not take long for it wake up and acknowledge by
408 	 * zeroing out ->command.
409 	 *
410 	 * ACPI specification doesn't provide any guidance on how long kernel
411 	 * has to wait for a wake up acknowledgement. It also doesn't provide
412 	 * a way to cancel a wake up request if it takes too long.
413 	 *
414 	 * In TDX environment, the VMM has control over how long it takes to
415 	 * wake up secondary. It can postpone scheduling secondary vCPU
416 	 * indefinitely. Giving up on wake up request and reporting error opens
417 	 * possible attack vector for VMM: it can wake up a secondary CPU when
418 	 * kernel doesn't expect it. Wait until positive result of the wake up
419 	 * request.
420 	 */
421 	while (READ_ONCE(acpi_mp_wake_mailbox->command))
422 		cpu_relax();
423 
424 	return 0;
425 }
426 #endif /* CONFIG_X86_64 */
427 #endif /* CONFIG_X86_LOCAL_APIC */
428 
429 #ifdef CONFIG_X86_IO_APIC
430 #define MP_ISA_BUS		0
431 
432 static int __init mp_register_ioapic_irq(u8 bus_irq, u8 polarity,
433 						u8 trigger, u32 gsi);
434 
435 static void __init mp_override_legacy_irq(u8 bus_irq, u8 polarity, u8 trigger,
436 					  u32 gsi)
437 {
438 	/*
439 	 * Check bus_irq boundary.
440 	 */
441 	if (bus_irq >= NR_IRQS_LEGACY) {
442 		pr_warn("Invalid bus_irq %u for legacy override\n", bus_irq);
443 		return;
444 	}
445 
446 	/*
447 	 * TBD: This check is for faulty timer entries, where the override
448 	 *      erroneously sets the trigger to level, resulting in a HUGE
449 	 *      increase of timer interrupts!
450 	 */
451 	if ((bus_irq == 0) && (trigger == 3))
452 		trigger = 1;
453 
454 	if (mp_register_ioapic_irq(bus_irq, polarity, trigger, gsi) < 0)
455 		return;
456 	/*
457 	 * Reset default identity mapping if gsi is also an legacy IRQ,
458 	 * otherwise there will be more than one entry with the same GSI
459 	 * and acpi_isa_irq_to_gsi() may give wrong result.
460 	 */
461 	if (gsi < nr_legacy_irqs() && isa_irq_to_gsi[gsi] == gsi)
462 		isa_irq_to_gsi[gsi] = INVALID_ACPI_IRQ;
463 	isa_irq_to_gsi[bus_irq] = gsi;
464 }
465 
466 static void mp_config_acpi_gsi(struct device *dev, u32 gsi, int trigger,
467 			int polarity)
468 {
469 #ifdef CONFIG_X86_MPPARSE
470 	struct mpc_intsrc mp_irq;
471 	struct pci_dev *pdev;
472 	unsigned char number;
473 	unsigned int devfn;
474 	int ioapic;
475 	u8 pin;
476 
477 	if (!acpi_ioapic)
478 		return;
479 	if (!dev || !dev_is_pci(dev))
480 		return;
481 
482 	pdev = to_pci_dev(dev);
483 	number = pdev->bus->number;
484 	devfn = pdev->devfn;
485 	pin = pdev->pin;
486 	/* print the entry should happen on mptable identically */
487 	mp_irq.type = MP_INTSRC;
488 	mp_irq.irqtype = mp_INT;
489 	mp_irq.irqflag = (trigger == ACPI_EDGE_SENSITIVE ? 4 : 0x0c) |
490 				(polarity == ACPI_ACTIVE_HIGH ? 1 : 3);
491 	mp_irq.srcbus = number;
492 	mp_irq.srcbusirq = (((devfn >> 3) & 0x1f) << 2) | ((pin - 1) & 3);
493 	ioapic = mp_find_ioapic(gsi);
494 	mp_irq.dstapic = mpc_ioapic_id(ioapic);
495 	mp_irq.dstirq = mp_find_ioapic_pin(ioapic, gsi);
496 
497 	mp_save_irq(&mp_irq);
498 #endif
499 }
500 
501 static int __init mp_register_ioapic_irq(u8 bus_irq, u8 polarity,
502 						u8 trigger, u32 gsi)
503 {
504 	struct mpc_intsrc mp_irq;
505 	int ioapic, pin;
506 
507 	/* Convert 'gsi' to 'ioapic.pin'(INTIN#) */
508 	ioapic = mp_find_ioapic(gsi);
509 	if (ioapic < 0) {
510 		pr_warn("Failed to find ioapic for gsi : %u\n", gsi);
511 		return ioapic;
512 	}
513 
514 	pin = mp_find_ioapic_pin(ioapic, gsi);
515 
516 	mp_irq.type = MP_INTSRC;
517 	mp_irq.irqtype = mp_INT;
518 	mp_irq.irqflag = (trigger << 2) | polarity;
519 	mp_irq.srcbus = MP_ISA_BUS;
520 	mp_irq.srcbusirq = bus_irq;
521 	mp_irq.dstapic = mpc_ioapic_id(ioapic);
522 	mp_irq.dstirq = pin;
523 
524 	mp_save_irq(&mp_irq);
525 
526 	return 0;
527 }
528 
529 static int __init
530 acpi_parse_ioapic(union acpi_subtable_headers * header, const unsigned long end)
531 {
532 	struct acpi_madt_io_apic *ioapic = NULL;
533 	struct ioapic_domain_cfg cfg = {
534 		.type = IOAPIC_DOMAIN_DYNAMIC,
535 		.ops = &mp_ioapic_irqdomain_ops,
536 	};
537 
538 	ioapic = (struct acpi_madt_io_apic *)header;
539 
540 	if (BAD_MADT_ENTRY(ioapic, end))
541 		return -EINVAL;
542 
543 	acpi_table_print_madt_entry(&header->common);
544 
545 	/* Statically assign IRQ numbers for IOAPICs hosting legacy IRQs */
546 	if (ioapic->global_irq_base < nr_legacy_irqs())
547 		cfg.type = IOAPIC_DOMAIN_LEGACY;
548 
549 	mp_register_ioapic(ioapic->id, ioapic->address, ioapic->global_irq_base,
550 			   &cfg);
551 
552 	return 0;
553 }
554 
555 /*
556  * Parse Interrupt Source Override for the ACPI SCI
557  */
558 static void __init acpi_sci_ioapic_setup(u8 bus_irq, u16 polarity, u16 trigger, u32 gsi)
559 {
560 	if (trigger == 0)	/* compatible SCI trigger is level */
561 		trigger = 3;
562 
563 	if (polarity == 0)	/* compatible SCI polarity is low */
564 		polarity = 3;
565 
566 	/* Command-line over-ride via acpi_sci= */
567 	if (acpi_sci_flags & ACPI_MADT_TRIGGER_MASK)
568 		trigger = (acpi_sci_flags & ACPI_MADT_TRIGGER_MASK) >> 2;
569 
570 	if (acpi_sci_flags & ACPI_MADT_POLARITY_MASK)
571 		polarity = acpi_sci_flags & ACPI_MADT_POLARITY_MASK;
572 
573 	if (bus_irq < NR_IRQS_LEGACY)
574 		mp_override_legacy_irq(bus_irq, polarity, trigger, gsi);
575 	else
576 		mp_register_ioapic_irq(bus_irq, polarity, trigger, gsi);
577 
578 	acpi_penalize_sci_irq(bus_irq, trigger, polarity);
579 
580 	/*
581 	 * stash over-ride to indicate we've been here
582 	 * and for later update of acpi_gbl_FADT
583 	 */
584 	acpi_sci_override_gsi = gsi;
585 	return;
586 }
587 
588 static int __init
589 acpi_parse_int_src_ovr(union acpi_subtable_headers * header,
590 		       const unsigned long end)
591 {
592 	struct acpi_madt_interrupt_override *intsrc = NULL;
593 
594 	intsrc = (struct acpi_madt_interrupt_override *)header;
595 
596 	if (BAD_MADT_ENTRY(intsrc, end))
597 		return -EINVAL;
598 
599 	acpi_table_print_madt_entry(&header->common);
600 
601 	if (intsrc->source_irq < NR_IRQS_LEGACY)
602 		acpi_int_src_ovr[intsrc->source_irq] = true;
603 
604 	if (intsrc->source_irq == acpi_gbl_FADT.sci_interrupt) {
605 		acpi_sci_ioapic_setup(intsrc->source_irq,
606 				      intsrc->inti_flags & ACPI_MADT_POLARITY_MASK,
607 				      (intsrc->inti_flags & ACPI_MADT_TRIGGER_MASK) >> 2,
608 				      intsrc->global_irq);
609 		return 0;
610 	}
611 
612 	if (intsrc->source_irq == 0) {
613 		if (acpi_skip_timer_override) {
614 			pr_warn("BIOS IRQ0 override ignored.\n");
615 			return 0;
616 		}
617 
618 		if ((intsrc->global_irq == 2) && acpi_fix_pin2_polarity
619 			&& (intsrc->inti_flags & ACPI_MADT_POLARITY_MASK)) {
620 			intsrc->inti_flags &= ~ACPI_MADT_POLARITY_MASK;
621 			pr_warn("BIOS IRQ0 pin2 override: forcing polarity to high active.\n");
622 		}
623 	}
624 
625 	mp_override_legacy_irq(intsrc->source_irq,
626 				intsrc->inti_flags & ACPI_MADT_POLARITY_MASK,
627 				(intsrc->inti_flags & ACPI_MADT_TRIGGER_MASK) >> 2,
628 				intsrc->global_irq);
629 
630 	return 0;
631 }
632 
633 static int __init
634 acpi_parse_nmi_src(union acpi_subtable_headers * header, const unsigned long end)
635 {
636 	struct acpi_madt_nmi_source *nmi_src = NULL;
637 
638 	nmi_src = (struct acpi_madt_nmi_source *)header;
639 
640 	if (BAD_MADT_ENTRY(nmi_src, end))
641 		return -EINVAL;
642 
643 	acpi_table_print_madt_entry(&header->common);
644 
645 	/* TBD: Support nimsrc entries? */
646 
647 	return 0;
648 }
649 
650 #endif				/* CONFIG_X86_IO_APIC */
651 
652 /*
653  * acpi_pic_sci_set_trigger()
654  *
655  * use ELCR to set PIC-mode trigger type for SCI
656  *
657  * If a PIC-mode SCI is not recognized or gives spurious IRQ7's
658  * it may require Edge Trigger -- use "acpi_sci=edge"
659  *
660  * Port 0x4d0-4d1 are ELCR1 and ELCR2, the Edge/Level Control Registers
661  * for the 8259 PIC.  bit[n] = 1 means irq[n] is Level, otherwise Edge.
662  * ELCR1 is IRQs 0-7 (IRQ 0, 1, 2 must be 0)
663  * ELCR2 is IRQs 8-15 (IRQ 8, 13 must be 0)
664  */
665 
666 void __init acpi_pic_sci_set_trigger(unsigned int irq, u16 trigger)
667 {
668 	unsigned int mask = 1 << irq;
669 	unsigned int old, new;
670 
671 	/* Real old ELCR mask */
672 	old = inb(PIC_ELCR1) | (inb(PIC_ELCR2) << 8);
673 
674 	/*
675 	 * If we use ACPI to set PCI IRQs, then we should clear ELCR
676 	 * since we will set it correctly as we enable the PCI irq
677 	 * routing.
678 	 */
679 	new = acpi_noirq ? old : 0;
680 
681 	/*
682 	 * Update SCI information in the ELCR, it isn't in the PCI
683 	 * routing tables..
684 	 */
685 	switch (trigger) {
686 	case 1:		/* Edge - clear */
687 		new &= ~mask;
688 		break;
689 	case 3:		/* Level - set */
690 		new |= mask;
691 		break;
692 	}
693 
694 	if (old == new)
695 		return;
696 
697 	pr_warn("setting ELCR to %04x (from %04x)\n", new, old);
698 	outb(new, PIC_ELCR1);
699 	outb(new >> 8, PIC_ELCR2);
700 }
701 
702 int acpi_gsi_to_irq(u32 gsi, unsigned int *irqp)
703 {
704 	int rc, irq, trigger, polarity;
705 
706 	if (acpi_irq_model == ACPI_IRQ_MODEL_PIC) {
707 		*irqp = gsi;
708 		return 0;
709 	}
710 
711 	rc = acpi_get_override_irq(gsi, &trigger, &polarity);
712 	if (rc)
713 		return rc;
714 
715 	trigger = trigger ? ACPI_LEVEL_SENSITIVE : ACPI_EDGE_SENSITIVE;
716 	polarity = polarity ? ACPI_ACTIVE_LOW : ACPI_ACTIVE_HIGH;
717 	irq = acpi_register_gsi(NULL, gsi, trigger, polarity);
718 	if (irq < 0)
719 		return irq;
720 
721 	*irqp = irq;
722 	return 0;
723 }
724 EXPORT_SYMBOL_GPL(acpi_gsi_to_irq);
725 
726 int acpi_isa_irq_to_gsi(unsigned isa_irq, u32 *gsi)
727 {
728 	if (isa_irq < nr_legacy_irqs() &&
729 	    isa_irq_to_gsi[isa_irq] != INVALID_ACPI_IRQ) {
730 		*gsi = isa_irq_to_gsi[isa_irq];
731 		return 0;
732 	}
733 
734 	return -1;
735 }
736 
737 static int acpi_register_gsi_pic(struct device *dev, u32 gsi,
738 				 int trigger, int polarity)
739 {
740 #ifdef CONFIG_PCI
741 	/*
742 	 * Make sure all (legacy) PCI IRQs are set as level-triggered.
743 	 */
744 	if (trigger == ACPI_LEVEL_SENSITIVE)
745 		elcr_set_level_irq(gsi);
746 #endif
747 
748 	return gsi;
749 }
750 
751 #ifdef CONFIG_X86_LOCAL_APIC
752 static int acpi_register_gsi_ioapic(struct device *dev, u32 gsi,
753 				    int trigger, int polarity)
754 {
755 	int irq = gsi;
756 #ifdef CONFIG_X86_IO_APIC
757 	int node;
758 	struct irq_alloc_info info;
759 
760 	node = dev ? dev_to_node(dev) : NUMA_NO_NODE;
761 	trigger = trigger == ACPI_EDGE_SENSITIVE ? 0 : 1;
762 	polarity = polarity == ACPI_ACTIVE_HIGH ? 0 : 1;
763 	ioapic_set_alloc_attr(&info, node, trigger, polarity);
764 
765 	mutex_lock(&acpi_ioapic_lock);
766 	irq = mp_map_gsi_to_irq(gsi, IOAPIC_MAP_ALLOC, &info);
767 	/* Don't set up the ACPI SCI because it's already set up */
768 	if (irq >= 0 && enable_update_mptable && gsi != acpi_gbl_FADT.sci_interrupt)
769 		mp_config_acpi_gsi(dev, gsi, trigger, polarity);
770 	mutex_unlock(&acpi_ioapic_lock);
771 #endif
772 
773 	return irq;
774 }
775 
776 static void acpi_unregister_gsi_ioapic(u32 gsi)
777 {
778 #ifdef CONFIG_X86_IO_APIC
779 	int irq;
780 
781 	mutex_lock(&acpi_ioapic_lock);
782 	irq = mp_map_gsi_to_irq(gsi, 0, NULL);
783 	if (irq > 0)
784 		mp_unmap_irq(irq);
785 	mutex_unlock(&acpi_ioapic_lock);
786 #endif
787 }
788 #endif
789 
790 int (*__acpi_register_gsi)(struct device *dev, u32 gsi,
791 			   int trigger, int polarity) = acpi_register_gsi_pic;
792 void (*__acpi_unregister_gsi)(u32 gsi) = NULL;
793 
794 #ifdef CONFIG_ACPI_SLEEP
795 int (*acpi_suspend_lowlevel)(void) = x86_acpi_suspend_lowlevel;
796 #else
797 int (*acpi_suspend_lowlevel)(void);
798 #endif
799 
800 /*
801  * success: return IRQ number (>=0)
802  * failure: return < 0
803  */
804 int acpi_register_gsi(struct device *dev, u32 gsi, int trigger, int polarity)
805 {
806 	return __acpi_register_gsi(dev, gsi, trigger, polarity);
807 }
808 EXPORT_SYMBOL_GPL(acpi_register_gsi);
809 
810 void acpi_unregister_gsi(u32 gsi)
811 {
812 	if (__acpi_unregister_gsi)
813 		__acpi_unregister_gsi(gsi);
814 }
815 EXPORT_SYMBOL_GPL(acpi_unregister_gsi);
816 
817 #ifdef CONFIG_X86_LOCAL_APIC
818 static void __init acpi_set_irq_model_ioapic(void)
819 {
820 	acpi_irq_model = ACPI_IRQ_MODEL_IOAPIC;
821 	__acpi_register_gsi = acpi_register_gsi_ioapic;
822 	__acpi_unregister_gsi = acpi_unregister_gsi_ioapic;
823 	acpi_ioapic = 1;
824 }
825 #endif
826 
827 /*
828  *  ACPI based hotplug support for CPU
829  */
830 #ifdef CONFIG_ACPI_HOTPLUG_CPU
831 #include <acpi/processor.h>
832 
833 static int acpi_map_cpu2node(acpi_handle handle, int cpu, int physid)
834 {
835 #ifdef CONFIG_ACPI_NUMA
836 	int nid;
837 
838 	nid = acpi_get_node(handle);
839 	if (nid != NUMA_NO_NODE) {
840 		set_apicid_to_node(physid, nid);
841 		numa_set_node(cpu, nid);
842 	}
843 #endif
844 	return 0;
845 }
846 
847 int acpi_map_cpu(acpi_handle handle, phys_cpuid_t physid, u32 acpi_id,
848 		 int *pcpu)
849 {
850 	int cpu;
851 
852 	cpu = acpi_register_lapic(physid, acpi_id, ACPI_MADT_ENABLED);
853 	if (cpu < 0) {
854 		pr_info("Unable to map lapic to logical cpu number\n");
855 		return cpu;
856 	}
857 
858 	acpi_processor_set_pdc(handle);
859 	acpi_map_cpu2node(handle, cpu, physid);
860 
861 	*pcpu = cpu;
862 	return 0;
863 }
864 EXPORT_SYMBOL(acpi_map_cpu);
865 
866 int acpi_unmap_cpu(int cpu)
867 {
868 #ifdef CONFIG_ACPI_NUMA
869 	set_apicid_to_node(per_cpu(x86_cpu_to_apicid, cpu), NUMA_NO_NODE);
870 #endif
871 
872 	per_cpu(x86_cpu_to_apicid, cpu) = BAD_APICID;
873 	set_cpu_present(cpu, false);
874 	num_processors--;
875 
876 	return (0);
877 }
878 EXPORT_SYMBOL(acpi_unmap_cpu);
879 #endif				/* CONFIG_ACPI_HOTPLUG_CPU */
880 
881 int acpi_register_ioapic(acpi_handle handle, u64 phys_addr, u32 gsi_base)
882 {
883 	int ret = -ENOSYS;
884 #ifdef CONFIG_ACPI_HOTPLUG_IOAPIC
885 	int ioapic_id;
886 	u64 addr;
887 	struct ioapic_domain_cfg cfg = {
888 		.type = IOAPIC_DOMAIN_DYNAMIC,
889 		.ops = &mp_ioapic_irqdomain_ops,
890 	};
891 
892 	ioapic_id = acpi_get_ioapic_id(handle, gsi_base, &addr);
893 	if (ioapic_id < 0) {
894 		unsigned long long uid;
895 		acpi_status status;
896 
897 		status = acpi_evaluate_integer(handle, METHOD_NAME__UID,
898 					       NULL, &uid);
899 		if (ACPI_FAILURE(status)) {
900 			acpi_handle_warn(handle, "failed to get IOAPIC ID.\n");
901 			return -EINVAL;
902 		}
903 		ioapic_id = (int)uid;
904 	}
905 
906 	mutex_lock(&acpi_ioapic_lock);
907 	ret  = mp_register_ioapic(ioapic_id, phys_addr, gsi_base, &cfg);
908 	mutex_unlock(&acpi_ioapic_lock);
909 #endif
910 
911 	return ret;
912 }
913 EXPORT_SYMBOL(acpi_register_ioapic);
914 
915 int acpi_unregister_ioapic(acpi_handle handle, u32 gsi_base)
916 {
917 	int ret = -ENOSYS;
918 
919 #ifdef CONFIG_ACPI_HOTPLUG_IOAPIC
920 	mutex_lock(&acpi_ioapic_lock);
921 	ret  = mp_unregister_ioapic(gsi_base);
922 	mutex_unlock(&acpi_ioapic_lock);
923 #endif
924 
925 	return ret;
926 }
927 EXPORT_SYMBOL(acpi_unregister_ioapic);
928 
929 /**
930  * acpi_ioapic_registered - Check whether IOAPIC associated with @gsi_base
931  *			    has been registered
932  * @handle:	ACPI handle of the IOAPIC device
933  * @gsi_base:	GSI base associated with the IOAPIC
934  *
935  * Assume caller holds some type of lock to serialize acpi_ioapic_registered()
936  * with acpi_register_ioapic()/acpi_unregister_ioapic().
937  */
938 int acpi_ioapic_registered(acpi_handle handle, u32 gsi_base)
939 {
940 	int ret = 0;
941 
942 #ifdef CONFIG_ACPI_HOTPLUG_IOAPIC
943 	mutex_lock(&acpi_ioapic_lock);
944 	ret  = mp_ioapic_registered(gsi_base);
945 	mutex_unlock(&acpi_ioapic_lock);
946 #endif
947 
948 	return ret;
949 }
950 
951 static int __init acpi_parse_sbf(struct acpi_table_header *table)
952 {
953 	struct acpi_table_boot *sb = (struct acpi_table_boot *)table;
954 
955 	sbf_port = sb->cmos_index;	/* Save CMOS port */
956 
957 	return 0;
958 }
959 
960 #ifdef CONFIG_HPET_TIMER
961 #include <asm/hpet.h>
962 
963 static struct resource *hpet_res __initdata;
964 
965 static int __init acpi_parse_hpet(struct acpi_table_header *table)
966 {
967 	struct acpi_table_hpet *hpet_tbl = (struct acpi_table_hpet *)table;
968 
969 	if (hpet_tbl->address.space_id != ACPI_SPACE_MEM) {
970 		pr_warn("HPET timers must be located in memory.\n");
971 		return -1;
972 	}
973 
974 	hpet_address = hpet_tbl->address.address;
975 	hpet_blockid = hpet_tbl->sequence;
976 
977 	/*
978 	 * Some broken BIOSes advertise HPET at 0x0. We really do not
979 	 * want to allocate a resource there.
980 	 */
981 	if (!hpet_address) {
982 		pr_warn("HPET id: %#x base: %#lx is invalid\n", hpet_tbl->id, hpet_address);
983 		return 0;
984 	}
985 #ifdef CONFIG_X86_64
986 	/*
987 	 * Some even more broken BIOSes advertise HPET at
988 	 * 0xfed0000000000000 instead of 0xfed00000. Fix it up and add
989 	 * some noise:
990 	 */
991 	if (hpet_address == 0xfed0000000000000UL) {
992 		if (!hpet_force_user) {
993 			pr_warn("HPET id: %#x base: 0xfed0000000000000 is bogus, try hpet=force on the kernel command line to fix it up to 0xfed00000.\n",
994 				hpet_tbl->id);
995 			hpet_address = 0;
996 			return 0;
997 		}
998 		pr_warn("HPET id: %#x base: 0xfed0000000000000 fixed up to 0xfed00000.\n",
999 			hpet_tbl->id);
1000 		hpet_address >>= 32;
1001 	}
1002 #endif
1003 	pr_info("HPET id: %#x base: %#lx\n", hpet_tbl->id, hpet_address);
1004 
1005 	/*
1006 	 * Allocate and initialize the HPET firmware resource for adding into
1007 	 * the resource tree during the lateinit timeframe.
1008 	 */
1009 #define HPET_RESOURCE_NAME_SIZE 9
1010 	hpet_res = memblock_alloc(sizeof(*hpet_res) + HPET_RESOURCE_NAME_SIZE,
1011 				  SMP_CACHE_BYTES);
1012 	if (!hpet_res)
1013 		panic("%s: Failed to allocate %zu bytes\n", __func__,
1014 		      sizeof(*hpet_res) + HPET_RESOURCE_NAME_SIZE);
1015 
1016 	hpet_res->name = (void *)&hpet_res[1];
1017 	hpet_res->flags = IORESOURCE_MEM;
1018 	snprintf((char *)hpet_res->name, HPET_RESOURCE_NAME_SIZE, "HPET %u",
1019 		 hpet_tbl->sequence);
1020 
1021 	hpet_res->start = hpet_address;
1022 	hpet_res->end = hpet_address + (1 * 1024) - 1;
1023 
1024 	return 0;
1025 }
1026 
1027 /*
1028  * hpet_insert_resource inserts the HPET resources used into the resource
1029  * tree.
1030  */
1031 static __init int hpet_insert_resource(void)
1032 {
1033 	if (!hpet_res)
1034 		return 1;
1035 
1036 	return insert_resource(&iomem_resource, hpet_res);
1037 }
1038 
1039 late_initcall(hpet_insert_resource);
1040 
1041 #else
1042 #define	acpi_parse_hpet	NULL
1043 #endif
1044 
1045 static int __init acpi_parse_fadt(struct acpi_table_header *table)
1046 {
1047 	if (!(acpi_gbl_FADT.boot_flags & ACPI_FADT_LEGACY_DEVICES)) {
1048 		pr_debug("no legacy devices present\n");
1049 		x86_platform.legacy.devices.pnpbios = 0;
1050 	}
1051 
1052 	if (acpi_gbl_FADT.header.revision >= FADT2_REVISION_ID &&
1053 	    !(acpi_gbl_FADT.boot_flags & ACPI_FADT_8042) &&
1054 	    x86_platform.legacy.i8042 != X86_LEGACY_I8042_PLATFORM_ABSENT) {
1055 		pr_debug("i8042 controller is absent\n");
1056 		x86_platform.legacy.i8042 = X86_LEGACY_I8042_FIRMWARE_ABSENT;
1057 	}
1058 
1059 	if (acpi_gbl_FADT.boot_flags & ACPI_FADT_NO_CMOS_RTC) {
1060 		pr_debug("not registering RTC platform device\n");
1061 		x86_platform.legacy.rtc = 0;
1062 	}
1063 
1064 	if (acpi_gbl_FADT.boot_flags & ACPI_FADT_NO_VGA) {
1065 		pr_debug("probing for VGA not safe\n");
1066 		x86_platform.legacy.no_vga = 1;
1067 	}
1068 
1069 #ifdef CONFIG_X86_PM_TIMER
1070 	/* detect the location of the ACPI PM Timer */
1071 	if (acpi_gbl_FADT.header.revision >= FADT2_REVISION_ID) {
1072 		/* FADT rev. 2 */
1073 		if (acpi_gbl_FADT.xpm_timer_block.space_id !=
1074 		    ACPI_ADR_SPACE_SYSTEM_IO)
1075 			return 0;
1076 
1077 		pmtmr_ioport = acpi_gbl_FADT.xpm_timer_block.address;
1078 		/*
1079 		 * "X" fields are optional extensions to the original V1.0
1080 		 * fields, so we must selectively expand V1.0 fields if the
1081 		 * corresponding X field is zero.
1082 	 	 */
1083 		if (!pmtmr_ioport)
1084 			pmtmr_ioport = acpi_gbl_FADT.pm_timer_block;
1085 	} else {
1086 		/* FADT rev. 1 */
1087 		pmtmr_ioport = acpi_gbl_FADT.pm_timer_block;
1088 	}
1089 	if (pmtmr_ioport)
1090 		pr_info("PM-Timer IO Port: %#x\n", pmtmr_ioport);
1091 #endif
1092 	return 0;
1093 }
1094 
1095 #ifdef	CONFIG_X86_LOCAL_APIC
1096 /*
1097  * Parse LAPIC entries in MADT
1098  * returns 0 on success, < 0 on error
1099  */
1100 
1101 static int __init early_acpi_parse_madt_lapic_addr_ovr(void)
1102 {
1103 	int count;
1104 
1105 	if (!boot_cpu_has(X86_FEATURE_APIC))
1106 		return -ENODEV;
1107 
1108 	/*
1109 	 * Note that the LAPIC address is obtained from the MADT (32-bit value)
1110 	 * and (optionally) overridden by a LAPIC_ADDR_OVR entry (64-bit value).
1111 	 */
1112 
1113 	count = acpi_table_parse_madt(ACPI_MADT_TYPE_LOCAL_APIC_OVERRIDE,
1114 				      acpi_parse_lapic_addr_ovr, 0);
1115 	if (count < 0) {
1116 		pr_err("Error parsing LAPIC address override entry\n");
1117 		return count;
1118 	}
1119 
1120 	register_lapic_address(acpi_lapic_addr);
1121 
1122 	return count;
1123 }
1124 
1125 static int __init acpi_parse_madt_lapic_entries(void)
1126 {
1127 	int count, x2count = 0;
1128 
1129 	if (!boot_cpu_has(X86_FEATURE_APIC))
1130 		return -ENODEV;
1131 
1132 	count = acpi_table_parse_madt(ACPI_MADT_TYPE_LOCAL_SAPIC,
1133 				      acpi_parse_sapic, MAX_LOCAL_APIC);
1134 
1135 	if (!count) {
1136 		count = acpi_table_parse_madt(ACPI_MADT_TYPE_LOCAL_APIC,
1137 					acpi_parse_lapic, MAX_LOCAL_APIC);
1138 		x2count = acpi_table_parse_madt(ACPI_MADT_TYPE_LOCAL_X2APIC,
1139 					acpi_parse_x2apic, MAX_LOCAL_APIC);
1140 	}
1141 	if (!count && !x2count) {
1142 		pr_err("No LAPIC entries present\n");
1143 		/* TBD: Cleanup to allow fallback to MPS */
1144 		return -ENODEV;
1145 	} else if (count < 0 || x2count < 0) {
1146 		pr_err("Error parsing LAPIC entry\n");
1147 		/* TBD: Cleanup to allow fallback to MPS */
1148 		return count;
1149 	}
1150 
1151 	x2count = acpi_table_parse_madt(ACPI_MADT_TYPE_LOCAL_X2APIC_NMI,
1152 					acpi_parse_x2apic_nmi, 0);
1153 	count = acpi_table_parse_madt(ACPI_MADT_TYPE_LOCAL_APIC_NMI,
1154 				      acpi_parse_lapic_nmi, 0);
1155 	if (count < 0 || x2count < 0) {
1156 		pr_err("Error parsing LAPIC NMI entry\n");
1157 		/* TBD: Cleanup to allow fallback to MPS */
1158 		return count;
1159 	}
1160 	return 0;
1161 }
1162 
1163 #ifdef CONFIG_X86_64
1164 static int __init acpi_parse_mp_wake(union acpi_subtable_headers *header,
1165 				     const unsigned long end)
1166 {
1167 	struct acpi_madt_multiproc_wakeup *mp_wake;
1168 
1169 	if (!IS_ENABLED(CONFIG_SMP))
1170 		return -ENODEV;
1171 
1172 	mp_wake = (struct acpi_madt_multiproc_wakeup *)header;
1173 	if (BAD_MADT_ENTRY(mp_wake, end))
1174 		return -EINVAL;
1175 
1176 	acpi_table_print_madt_entry(&header->common);
1177 
1178 	acpi_mp_wake_mailbox_paddr = mp_wake->base_address;
1179 
1180 	apic_update_callback(wakeup_secondary_cpu_64, acpi_wakeup_cpu);
1181 
1182 	return 0;
1183 }
1184 #endif				/* CONFIG_X86_64 */
1185 #endif				/* CONFIG_X86_LOCAL_APIC */
1186 
1187 #ifdef	CONFIG_X86_IO_APIC
1188 static void __init mp_config_acpi_legacy_irqs(void)
1189 {
1190 	int i;
1191 	struct mpc_intsrc mp_irq;
1192 
1193 #ifdef CONFIG_EISA
1194 	/*
1195 	 * Fabricate the legacy ISA bus (bus #31).
1196 	 */
1197 	mp_bus_id_to_type[MP_ISA_BUS] = MP_BUS_ISA;
1198 #endif
1199 	set_bit(MP_ISA_BUS, mp_bus_not_pci);
1200 	pr_debug("Bus #%d is ISA (nIRQs: %d)\n", MP_ISA_BUS, nr_legacy_irqs());
1201 
1202 	/*
1203 	 * Use the default configuration for the IRQs 0-15.  Unless
1204 	 * overridden by (MADT) interrupt source override entries.
1205 	 */
1206 	for (i = 0; i < nr_legacy_irqs(); i++) {
1207 		int ioapic, pin;
1208 		unsigned int dstapic;
1209 		int idx;
1210 		u32 gsi;
1211 
1212 		/* Locate the gsi that irq i maps to. */
1213 		if (acpi_isa_irq_to_gsi(i, &gsi))
1214 			continue;
1215 
1216 		/*
1217 		 * Locate the IOAPIC that manages the ISA IRQ.
1218 		 */
1219 		ioapic = mp_find_ioapic(gsi);
1220 		if (ioapic < 0)
1221 			continue;
1222 		pin = mp_find_ioapic_pin(ioapic, gsi);
1223 		dstapic = mpc_ioapic_id(ioapic);
1224 
1225 		for (idx = 0; idx < mp_irq_entries; idx++) {
1226 			struct mpc_intsrc *irq = mp_irqs + idx;
1227 
1228 			/* Do we already have a mapping for this ISA IRQ? */
1229 			if (irq->srcbus == MP_ISA_BUS && irq->srcbusirq == i)
1230 				break;
1231 
1232 			/* Do we already have a mapping for this IOAPIC pin */
1233 			if (irq->dstapic == dstapic && irq->dstirq == pin)
1234 				break;
1235 		}
1236 
1237 		if (idx != mp_irq_entries) {
1238 			pr_debug("ACPI: IRQ%d used by override.\n", i);
1239 			continue;	/* IRQ already used */
1240 		}
1241 
1242 		mp_irq.type = MP_INTSRC;
1243 		mp_irq.irqflag = 0;	/* Conforming */
1244 		mp_irq.srcbus = MP_ISA_BUS;
1245 		mp_irq.dstapic = dstapic;
1246 		mp_irq.irqtype = mp_INT;
1247 		mp_irq.srcbusirq = i; /* Identity mapped */
1248 		mp_irq.dstirq = pin;
1249 
1250 		mp_save_irq(&mp_irq);
1251 	}
1252 }
1253 
1254 /*
1255  * Parse IOAPIC related entries in MADT
1256  * returns 0 on success, < 0 on error
1257  */
1258 static int __init acpi_parse_madt_ioapic_entries(void)
1259 {
1260 	int count;
1261 
1262 	/*
1263 	 * ACPI interpreter is required to complete interrupt setup,
1264 	 * so if it is off, don't enumerate the io-apics with ACPI.
1265 	 * If MPS is present, it will handle them,
1266 	 * otherwise the system will stay in PIC mode
1267 	 */
1268 	if (acpi_disabled || acpi_noirq)
1269 		return -ENODEV;
1270 
1271 	if (!boot_cpu_has(X86_FEATURE_APIC))
1272 		return -ENODEV;
1273 
1274 	/*
1275 	 * if "noapic" boot option, don't look for IO-APICs
1276 	 */
1277 	if (ioapic_is_disabled) {
1278 		pr_info("Skipping IOAPIC probe due to 'noapic' option.\n");
1279 		return -ENODEV;
1280 	}
1281 
1282 	count = acpi_table_parse_madt(ACPI_MADT_TYPE_IO_APIC, acpi_parse_ioapic,
1283 				      MAX_IO_APICS);
1284 	if (!count) {
1285 		pr_err("No IOAPIC entries present\n");
1286 		return -ENODEV;
1287 	} else if (count < 0) {
1288 		pr_err("Error parsing IOAPIC entry\n");
1289 		return count;
1290 	}
1291 
1292 	count = acpi_table_parse_madt(ACPI_MADT_TYPE_INTERRUPT_OVERRIDE,
1293 				      acpi_parse_int_src_ovr, nr_irqs);
1294 	if (count < 0) {
1295 		pr_err("Error parsing interrupt source overrides entry\n");
1296 		/* TBD: Cleanup to allow fallback to MPS */
1297 		return count;
1298 	}
1299 
1300 	/*
1301 	 * If BIOS did not supply an INT_SRC_OVR for the SCI
1302 	 * pretend we got one so we can set the SCI flags.
1303 	 * But ignore setting up SCI on hardware reduced platforms.
1304 	 */
1305 	if (acpi_sci_override_gsi == INVALID_ACPI_IRQ && !acpi_gbl_reduced_hardware)
1306 		acpi_sci_ioapic_setup(acpi_gbl_FADT.sci_interrupt, 0, 0,
1307 				      acpi_gbl_FADT.sci_interrupt);
1308 
1309 	/* Fill in identity legacy mappings where no override */
1310 	mp_config_acpi_legacy_irqs();
1311 
1312 	count = acpi_table_parse_madt(ACPI_MADT_TYPE_NMI_SOURCE,
1313 				      acpi_parse_nmi_src, nr_irqs);
1314 	if (count < 0) {
1315 		pr_err("Error parsing NMI SRC entry\n");
1316 		/* TBD: Cleanup to allow fallback to MPS */
1317 		return count;
1318 	}
1319 
1320 	return 0;
1321 }
1322 #else
1323 static inline int acpi_parse_madt_ioapic_entries(void)
1324 {
1325 	return -1;
1326 }
1327 #endif	/* !CONFIG_X86_IO_APIC */
1328 
1329 static void __init early_acpi_process_madt(void)
1330 {
1331 #ifdef CONFIG_X86_LOCAL_APIC
1332 	int error;
1333 
1334 	if (!acpi_table_parse(ACPI_SIG_MADT, acpi_parse_madt)) {
1335 
1336 		/*
1337 		 * Parse MADT LAPIC entries
1338 		 */
1339 		error = early_acpi_parse_madt_lapic_addr_ovr();
1340 		if (!error) {
1341 			acpi_lapic = 1;
1342 			smp_found_config = 1;
1343 		}
1344 		if (error == -EINVAL) {
1345 			/*
1346 			 * Dell Precision Workstation 410, 610 come here.
1347 			 */
1348 			pr_err("Invalid BIOS MADT, disabling ACPI\n");
1349 			disable_acpi();
1350 		}
1351 	}
1352 #endif
1353 }
1354 
1355 static void __init acpi_process_madt(void)
1356 {
1357 #ifdef CONFIG_X86_LOCAL_APIC
1358 	int error;
1359 
1360 	if (!acpi_table_parse(ACPI_SIG_MADT, acpi_parse_madt)) {
1361 
1362 		/*
1363 		 * Parse MADT LAPIC entries
1364 		 */
1365 		error = acpi_parse_madt_lapic_entries();
1366 		if (!error) {
1367 			acpi_lapic = 1;
1368 
1369 			/*
1370 			 * Parse MADT IO-APIC entries
1371 			 */
1372 			mutex_lock(&acpi_ioapic_lock);
1373 			error = acpi_parse_madt_ioapic_entries();
1374 			mutex_unlock(&acpi_ioapic_lock);
1375 			if (!error) {
1376 				acpi_set_irq_model_ioapic();
1377 
1378 				smp_found_config = 1;
1379 			}
1380 
1381 #ifdef CONFIG_X86_64
1382 			/*
1383 			 * Parse MADT MP Wake entry.
1384 			 */
1385 			acpi_table_parse_madt(ACPI_MADT_TYPE_MULTIPROC_WAKEUP,
1386 					      acpi_parse_mp_wake, 1);
1387 #endif
1388 		}
1389 		if (error == -EINVAL) {
1390 			/*
1391 			 * Dell Precision Workstation 410, 610 come here.
1392 			 */
1393 			pr_err("Invalid BIOS MADT, disabling ACPI\n");
1394 			disable_acpi();
1395 		}
1396 	} else {
1397 		/*
1398  		 * ACPI found no MADT, and so ACPI wants UP PIC mode.
1399  		 * In the event an MPS table was found, forget it.
1400  		 * Boot with "acpi=off" to use MPS on such a system.
1401  		 */
1402 		if (smp_found_config) {
1403 			pr_warn("No APIC-table, disabling MPS\n");
1404 			smp_found_config = 0;
1405 		}
1406 	}
1407 
1408 	/*
1409 	 * ACPI supports both logical (e.g. Hyper-Threading) and physical
1410 	 * processors, where MPS only supports physical.
1411 	 */
1412 	if (acpi_lapic && acpi_ioapic)
1413 		pr_info("Using ACPI (MADT) for SMP configuration information\n");
1414 	else if (acpi_lapic)
1415 		pr_info("Using ACPI for processor (LAPIC) configuration information\n");
1416 #endif
1417 	return;
1418 }
1419 
1420 static int __init disable_acpi_irq(const struct dmi_system_id *d)
1421 {
1422 	if (!acpi_force) {
1423 		pr_notice("%s detected: force use of acpi=noirq\n", d->ident);
1424 		acpi_noirq_set();
1425 	}
1426 	return 0;
1427 }
1428 
1429 static int __init disable_acpi_pci(const struct dmi_system_id *d)
1430 {
1431 	if (!acpi_force) {
1432 		pr_notice("%s detected: force use of pci=noacpi\n", d->ident);
1433 		acpi_disable_pci();
1434 	}
1435 	return 0;
1436 }
1437 
1438 static int __init disable_acpi_xsdt(const struct dmi_system_id *d)
1439 {
1440 	if (!acpi_force) {
1441 		pr_notice("%s detected: force use of acpi=rsdt\n", d->ident);
1442 		acpi_gbl_do_not_use_xsdt = TRUE;
1443 	} else {
1444 		pr_notice("Warning: DMI blacklist says broken, but acpi XSDT forced\n");
1445 	}
1446 	return 0;
1447 }
1448 
1449 static int __init dmi_disable_acpi(const struct dmi_system_id *d)
1450 {
1451 	if (!acpi_force) {
1452 		pr_notice("%s detected: acpi off\n", d->ident);
1453 		disable_acpi();
1454 	} else {
1455 		pr_notice("Warning: DMI blacklist says broken, but acpi forced\n");
1456 	}
1457 	return 0;
1458 }
1459 
1460 /*
1461  * Force ignoring BIOS IRQ0 override
1462  */
1463 static int __init dmi_ignore_irq0_timer_override(const struct dmi_system_id *d)
1464 {
1465 	if (!acpi_skip_timer_override) {
1466 		pr_notice("%s detected: Ignoring BIOS IRQ0 override\n",
1467 			d->ident);
1468 		acpi_skip_timer_override = 1;
1469 	}
1470 	return 0;
1471 }
1472 
1473 /*
1474  * ACPI offers an alternative platform interface model that removes
1475  * ACPI hardware requirements for platforms that do not implement
1476  * the PC Architecture.
1477  *
1478  * We initialize the Hardware-reduced ACPI model here:
1479  */
1480 void __init acpi_generic_reduced_hw_init(void)
1481 {
1482 	/*
1483 	 * Override x86_init functions and bypass legacy PIC in
1484 	 * hardware reduced ACPI mode.
1485 	 */
1486 	x86_init.timers.timer_init	= x86_init_noop;
1487 	x86_init.irqs.pre_vector_init	= x86_init_noop;
1488 	legacy_pic			= &null_legacy_pic;
1489 }
1490 
1491 static void __init acpi_reduced_hw_init(void)
1492 {
1493 	if (acpi_gbl_reduced_hardware)
1494 		x86_init.acpi.reduced_hw_early_init();
1495 }
1496 
1497 /*
1498  * If your system is blacklisted here, but you find that acpi=force
1499  * works for you, please contact linux-acpi@vger.kernel.org
1500  */
1501 static const struct dmi_system_id acpi_dmi_table[] __initconst = {
1502 	/*
1503 	 * Boxes that need ACPI disabled
1504 	 */
1505 	{
1506 	 .callback = dmi_disable_acpi,
1507 	 .ident = "IBM Thinkpad",
1508 	 .matches = {
1509 		     DMI_MATCH(DMI_BOARD_VENDOR, "IBM"),
1510 		     DMI_MATCH(DMI_BOARD_NAME, "2629H1G"),
1511 		     },
1512 	 },
1513 
1514 	/*
1515 	 * Boxes that need ACPI PCI IRQ routing disabled
1516 	 */
1517 	{
1518 	 .callback = disable_acpi_irq,
1519 	 .ident = "ASUS A7V",
1520 	 .matches = {
1521 		     DMI_MATCH(DMI_BOARD_VENDOR, "ASUSTeK Computer INC"),
1522 		     DMI_MATCH(DMI_BOARD_NAME, "<A7V>"),
1523 		     /* newer BIOS, Revision 1011, does work */
1524 		     DMI_MATCH(DMI_BIOS_VERSION,
1525 			       "ASUS A7V ACPI BIOS Revision 1007"),
1526 		     },
1527 	 },
1528 	{
1529 		/*
1530 		 * Latest BIOS for IBM 600E (1.16) has bad pcinum
1531 		 * for LPC bridge, which is needed for the PCI
1532 		 * interrupt links to work. DSDT fix is in bug 5966.
1533 		 * 2645, 2646 model numbers are shared with 600/600E/600X
1534 		 */
1535 	 .callback = disable_acpi_irq,
1536 	 .ident = "IBM Thinkpad 600 Series 2645",
1537 	 .matches = {
1538 		     DMI_MATCH(DMI_BOARD_VENDOR, "IBM"),
1539 		     DMI_MATCH(DMI_BOARD_NAME, "2645"),
1540 		     },
1541 	 },
1542 	{
1543 	 .callback = disable_acpi_irq,
1544 	 .ident = "IBM Thinkpad 600 Series 2646",
1545 	 .matches = {
1546 		     DMI_MATCH(DMI_BOARD_VENDOR, "IBM"),
1547 		     DMI_MATCH(DMI_BOARD_NAME, "2646"),
1548 		     },
1549 	 },
1550 	/*
1551 	 * Boxes that need ACPI PCI IRQ routing and PCI scan disabled
1552 	 */
1553 	{			/* _BBN 0 bug */
1554 	 .callback = disable_acpi_pci,
1555 	 .ident = "ASUS PR-DLS",
1556 	 .matches = {
1557 		     DMI_MATCH(DMI_BOARD_VENDOR, "ASUSTeK Computer INC."),
1558 		     DMI_MATCH(DMI_BOARD_NAME, "PR-DLS"),
1559 		     DMI_MATCH(DMI_BIOS_VERSION,
1560 			       "ASUS PR-DLS ACPI BIOS Revision 1010"),
1561 		     DMI_MATCH(DMI_BIOS_DATE, "03/21/2003")
1562 		     },
1563 	 },
1564 	{
1565 	 .callback = disable_acpi_pci,
1566 	 .ident = "Acer TravelMate 36x Laptop",
1567 	 .matches = {
1568 		     DMI_MATCH(DMI_SYS_VENDOR, "Acer"),
1569 		     DMI_MATCH(DMI_PRODUCT_NAME, "TravelMate 360"),
1570 		     },
1571 	 },
1572 	/*
1573 	 * Boxes that need ACPI XSDT use disabled due to corrupted tables
1574 	 */
1575 	{
1576 	 .callback = disable_acpi_xsdt,
1577 	 .ident = "Advantech DAC-BJ01",
1578 	 .matches = {
1579 		     DMI_MATCH(DMI_SYS_VENDOR, "NEC"),
1580 		     DMI_MATCH(DMI_PRODUCT_NAME, "Bearlake CRB Board"),
1581 		     DMI_MATCH(DMI_BIOS_VERSION, "V1.12"),
1582 		     DMI_MATCH(DMI_BIOS_DATE, "02/01/2011"),
1583 		     },
1584 	 },
1585 	{}
1586 };
1587 
1588 /* second table for DMI checks that should run after early-quirks */
1589 static const struct dmi_system_id acpi_dmi_table_late[] __initconst = {
1590 	/*
1591 	 * HP laptops which use a DSDT reporting as HP/SB400/10000,
1592 	 * which includes some code which overrides all temperature
1593 	 * trip points to 16C if the INTIN2 input of the I/O APIC
1594 	 * is enabled.  This input is incorrectly designated the
1595 	 * ISA IRQ 0 via an interrupt source override even though
1596 	 * it is wired to the output of the master 8259A and INTIN0
1597 	 * is not connected at all.  Force ignoring BIOS IRQ0
1598 	 * override in that cases.
1599 	 */
1600 	{
1601 	 .callback = dmi_ignore_irq0_timer_override,
1602 	 .ident = "HP nx6115 laptop",
1603 	 .matches = {
1604 		     DMI_MATCH(DMI_SYS_VENDOR, "Hewlett-Packard"),
1605 		     DMI_MATCH(DMI_PRODUCT_NAME, "HP Compaq nx6115"),
1606 		     },
1607 	 },
1608 	{
1609 	 .callback = dmi_ignore_irq0_timer_override,
1610 	 .ident = "HP NX6125 laptop",
1611 	 .matches = {
1612 		     DMI_MATCH(DMI_SYS_VENDOR, "Hewlett-Packard"),
1613 		     DMI_MATCH(DMI_PRODUCT_NAME, "HP Compaq nx6125"),
1614 		     },
1615 	 },
1616 	{
1617 	 .callback = dmi_ignore_irq0_timer_override,
1618 	 .ident = "HP NX6325 laptop",
1619 	 .matches = {
1620 		     DMI_MATCH(DMI_SYS_VENDOR, "Hewlett-Packard"),
1621 		     DMI_MATCH(DMI_PRODUCT_NAME, "HP Compaq nx6325"),
1622 		     },
1623 	 },
1624 	{
1625 	 .callback = dmi_ignore_irq0_timer_override,
1626 	 .ident = "HP 6715b laptop",
1627 	 .matches = {
1628 		     DMI_MATCH(DMI_SYS_VENDOR, "Hewlett-Packard"),
1629 		     DMI_MATCH(DMI_PRODUCT_NAME, "HP Compaq 6715b"),
1630 		     },
1631 	 },
1632 	{
1633 	 .callback = dmi_ignore_irq0_timer_override,
1634 	 .ident = "FUJITSU SIEMENS",
1635 	 .matches = {
1636 		     DMI_MATCH(DMI_SYS_VENDOR, "FUJITSU SIEMENS"),
1637 		     DMI_MATCH(DMI_PRODUCT_NAME, "AMILO PRO V2030"),
1638 		     },
1639 	 },
1640 	{}
1641 };
1642 
1643 /*
1644  * acpi_boot_table_init() and acpi_boot_init()
1645  *  called from setup_arch(), always.
1646  *	1. checksums all tables
1647  *	2. enumerates lapics
1648  *	3. enumerates io-apics
1649  *
1650  * acpi_table_init() is separate to allow reading SRAT without
1651  * other side effects.
1652  *
1653  * side effects of acpi_boot_init:
1654  *	acpi_lapic = 1 if LAPIC found
1655  *	acpi_ioapic = 1 if IOAPIC found
1656  *	if (acpi_lapic && acpi_ioapic) smp_found_config = 1;
1657  *	if acpi_blacklisted() acpi_disabled = 1;
1658  *	acpi_irq_model=...
1659  *	...
1660  */
1661 
1662 void __init acpi_boot_table_init(void)
1663 {
1664 	dmi_check_system(acpi_dmi_table);
1665 
1666 	/*
1667 	 * If acpi_disabled, bail out
1668 	 */
1669 	if (acpi_disabled)
1670 		return;
1671 
1672 	/*
1673 	 * Initialize the ACPI boot-time table parser.
1674 	 */
1675 	if (acpi_locate_initial_tables())
1676 		disable_acpi();
1677 	else
1678 		acpi_reserve_initial_tables();
1679 }
1680 
1681 int __init early_acpi_boot_init(void)
1682 {
1683 	if (acpi_disabled)
1684 		return 1;
1685 
1686 	acpi_table_init_complete();
1687 
1688 	acpi_table_parse(ACPI_SIG_BOOT, acpi_parse_sbf);
1689 
1690 	/*
1691 	 * blacklist may disable ACPI entirely
1692 	 */
1693 	if (acpi_blacklisted()) {
1694 		if (acpi_force) {
1695 			pr_warn("acpi=force override\n");
1696 		} else {
1697 			pr_warn("Disabling ACPI support\n");
1698 			disable_acpi();
1699 			return 1;
1700 		}
1701 	}
1702 
1703 	/*
1704 	 * Process the Multiple APIC Description Table (MADT), if present
1705 	 */
1706 	early_acpi_process_madt();
1707 
1708 	/*
1709 	 * Hardware-reduced ACPI mode initialization:
1710 	 */
1711 	acpi_reduced_hw_init();
1712 
1713 	return 0;
1714 }
1715 
1716 int __init acpi_boot_init(void)
1717 {
1718 	/* those are executed after early-quirks are executed */
1719 	dmi_check_system(acpi_dmi_table_late);
1720 
1721 	/*
1722 	 * If acpi_disabled, bail out
1723 	 */
1724 	if (acpi_disabled)
1725 		return 1;
1726 
1727 	acpi_table_parse(ACPI_SIG_BOOT, acpi_parse_sbf);
1728 
1729 	/*
1730 	 * set sci_int and PM timer address
1731 	 */
1732 	acpi_table_parse(ACPI_SIG_FADT, acpi_parse_fadt);
1733 
1734 	/*
1735 	 * Process the Multiple APIC Description Table (MADT), if present
1736 	 */
1737 	acpi_process_madt();
1738 
1739 	acpi_table_parse(ACPI_SIG_HPET, acpi_parse_hpet);
1740 	if (IS_ENABLED(CONFIG_ACPI_BGRT) && !acpi_nobgrt)
1741 		acpi_table_parse(ACPI_SIG_BGRT, acpi_parse_bgrt);
1742 
1743 	if (!acpi_noirq)
1744 		x86_init.pci.init = pci_acpi_init;
1745 
1746 	/* Do not enable ACPI SPCR console by default */
1747 	acpi_parse_spcr(earlycon_acpi_spcr_enable, false);
1748 	return 0;
1749 }
1750 
1751 static int __init parse_acpi(char *arg)
1752 {
1753 	if (!arg)
1754 		return -EINVAL;
1755 
1756 	/* "acpi=off" disables both ACPI table parsing and interpreter */
1757 	if (strcmp(arg, "off") == 0) {
1758 		disable_acpi();
1759 	}
1760 	/* acpi=force to over-ride black-list */
1761 	else if (strcmp(arg, "force") == 0) {
1762 		acpi_force = 1;
1763 		acpi_disabled = 0;
1764 	}
1765 	/* acpi=strict disables out-of-spec workarounds */
1766 	else if (strcmp(arg, "strict") == 0) {
1767 		acpi_strict = 1;
1768 	}
1769 	/* acpi=rsdt use RSDT instead of XSDT */
1770 	else if (strcmp(arg, "rsdt") == 0) {
1771 		acpi_gbl_do_not_use_xsdt = TRUE;
1772 	}
1773 	/* "acpi=noirq" disables ACPI interrupt routing */
1774 	else if (strcmp(arg, "noirq") == 0) {
1775 		acpi_noirq_set();
1776 	}
1777 	/* "acpi=copy_dsdt" copies DSDT */
1778 	else if (strcmp(arg, "copy_dsdt") == 0) {
1779 		acpi_gbl_copy_dsdt_locally = 1;
1780 	}
1781 	/* "acpi=nocmcff" disables FF mode for corrected errors */
1782 	else if (strcmp(arg, "nocmcff") == 0) {
1783 		acpi_disable_cmcff = 1;
1784 	} else {
1785 		/* Core will printk when we return error. */
1786 		return -EINVAL;
1787 	}
1788 	return 0;
1789 }
1790 early_param("acpi", parse_acpi);
1791 
1792 static int __init parse_acpi_bgrt(char *arg)
1793 {
1794 	acpi_nobgrt = true;
1795 	return 0;
1796 }
1797 early_param("bgrt_disable", parse_acpi_bgrt);
1798 
1799 /* FIXME: Using pci= for an ACPI parameter is a travesty. */
1800 static int __init parse_pci(char *arg)
1801 {
1802 	if (arg && strcmp(arg, "noacpi") == 0)
1803 		acpi_disable_pci();
1804 	return 0;
1805 }
1806 early_param("pci", parse_pci);
1807 
1808 int __init acpi_mps_check(void)
1809 {
1810 #if defined(CONFIG_X86_LOCAL_APIC) && !defined(CONFIG_X86_MPPARSE)
1811 /* mptable code is not built-in*/
1812 	if (acpi_disabled || acpi_noirq) {
1813 		pr_warn("MPS support code is not built-in, using acpi=off or acpi=noirq or pci=noacpi may have problem\n");
1814 		return 1;
1815 	}
1816 #endif
1817 	return 0;
1818 }
1819 
1820 #ifdef CONFIG_X86_IO_APIC
1821 static int __init parse_acpi_skip_timer_override(char *arg)
1822 {
1823 	acpi_skip_timer_override = 1;
1824 	return 0;
1825 }
1826 early_param("acpi_skip_timer_override", parse_acpi_skip_timer_override);
1827 
1828 static int __init parse_acpi_use_timer_override(char *arg)
1829 {
1830 	acpi_use_timer_override = 1;
1831 	return 0;
1832 }
1833 early_param("acpi_use_timer_override", parse_acpi_use_timer_override);
1834 #endif /* CONFIG_X86_IO_APIC */
1835 
1836 static int __init setup_acpi_sci(char *s)
1837 {
1838 	if (!s)
1839 		return -EINVAL;
1840 	if (!strcmp(s, "edge"))
1841 		acpi_sci_flags =  ACPI_MADT_TRIGGER_EDGE |
1842 			(acpi_sci_flags & ~ACPI_MADT_TRIGGER_MASK);
1843 	else if (!strcmp(s, "level"))
1844 		acpi_sci_flags = ACPI_MADT_TRIGGER_LEVEL |
1845 			(acpi_sci_flags & ~ACPI_MADT_TRIGGER_MASK);
1846 	else if (!strcmp(s, "high"))
1847 		acpi_sci_flags = ACPI_MADT_POLARITY_ACTIVE_HIGH |
1848 			(acpi_sci_flags & ~ACPI_MADT_POLARITY_MASK);
1849 	else if (!strcmp(s, "low"))
1850 		acpi_sci_flags = ACPI_MADT_POLARITY_ACTIVE_LOW |
1851 			(acpi_sci_flags & ~ACPI_MADT_POLARITY_MASK);
1852 	else
1853 		return -EINVAL;
1854 	return 0;
1855 }
1856 early_param("acpi_sci", setup_acpi_sci);
1857 
1858 int __acpi_acquire_global_lock(unsigned int *lock)
1859 {
1860 	unsigned int old, new, val;
1861 
1862 	old = READ_ONCE(*lock);
1863 	do {
1864 		val = (old >> 1) & 0x1;
1865 		new = (old & ~0x3) + 2 + val;
1866 	} while (!try_cmpxchg(lock, &old, new));
1867 
1868 	if (val)
1869 		return 0;
1870 
1871 	return -1;
1872 }
1873 
1874 int __acpi_release_global_lock(unsigned int *lock)
1875 {
1876 	unsigned int old, new;
1877 
1878 	old = READ_ONCE(*lock);
1879 	do {
1880 		new = old & ~0x3;
1881 	} while (!try_cmpxchg(lock, &old, new));
1882 	return old & 0x1;
1883 }
1884 
1885 void __init arch_reserve_mem_area(acpi_physical_address addr, size_t size)
1886 {
1887 	e820__range_add(addr, size, E820_TYPE_NVS);
1888 	e820__update_table_print();
1889 }
1890 
1891 void x86_default_set_root_pointer(u64 addr)
1892 {
1893 	boot_params.acpi_rsdp_addr = addr;
1894 }
1895 
1896 u64 x86_default_get_root_pointer(void)
1897 {
1898 	return boot_params.acpi_rsdp_addr;
1899 }
1900