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v6.8
   1// SPDX-License-Identifier: GPL-2.0
   2/*
   3 *	Intel IO-APIC support for multi-Pentium hosts.
   4 *
   5 *	Copyright (C) 1997, 1998, 1999, 2000, 2009 Ingo Molnar, Hajnalka Szabo
   6 *
   7 *	Many thanks to Stig Venaas for trying out countless experimental
   8 *	patches and reporting/debugging problems patiently!
   9 *
  10 *	(c) 1999, Multiple IO-APIC support, developed by
  11 *	Ken-ichi Yaku <yaku@css1.kbnes.nec.co.jp> and
  12 *      Hidemi Kishimoto <kisimoto@css1.kbnes.nec.co.jp>,
  13 *	further tested and cleaned up by Zach Brown <zab@redhat.com>
  14 *	and Ingo Molnar <mingo@redhat.com>
  15 *
  16 *	Fixes
  17 *	Maciej W. Rozycki	:	Bits for genuine 82489DX APICs;
  18 *					thanks to Eric Gilmore
  19 *					and Rolf G. Tews
  20 *					for testing these extensively
  21 *	Paul Diefenbaugh	:	Added full ACPI support
  22 *
  23 * Historical information which is worth to be preserved:
  24 *
  25 * - SiS APIC rmw bug:
  26 *
  27 *	We used to have a workaround for a bug in SiS chips which
  28 *	required to rewrite the index register for a read-modify-write
  29 *	operation as the chip lost the index information which was
  30 *	setup for the read already. We cache the data now, so that
  31 *	workaround has been removed.
  32 */
  33
  34#include <linux/mm.h>
  35#include <linux/interrupt.h>
  36#include <linux/irq.h>
  37#include <linux/init.h>
  38#include <linux/delay.h>
  39#include <linux/sched.h>
  40#include <linux/pci.h>
  41#include <linux/mc146818rtc.h>
  42#include <linux/compiler.h>
  43#include <linux/acpi.h>
  44#include <linux/export.h>
  45#include <linux/syscore_ops.h>
  46#include <linux/freezer.h>
  47#include <linux/kthread.h>
  48#include <linux/jiffies.h>	/* time_after() */
  49#include <linux/slab.h>
  50#include <linux/memblock.h>
  51#include <linux/msi.h>
  52
  53#include <asm/irqdomain.h>
  54#include <asm/io.h>
  55#include <asm/smp.h>
  56#include <asm/cpu.h>
  57#include <asm/desc.h>
  58#include <asm/proto.h>
  59#include <asm/acpi.h>
  60#include <asm/dma.h>
  61#include <asm/timer.h>
  62#include <asm/time.h>
  63#include <asm/i8259.h>
  64#include <asm/setup.h>
  65#include <asm/irq_remapping.h>
  66#include <asm/hw_irq.h>
  67#include <asm/apic.h>
  68#include <asm/pgtable.h>
  69#include <asm/x86_init.h>
  70
  71#define	for_each_ioapic(idx)		\
  72	for ((idx) = 0; (idx) < nr_ioapics; (idx)++)
  73#define	for_each_ioapic_reverse(idx)	\
  74	for ((idx) = nr_ioapics - 1; (idx) >= 0; (idx)--)
  75#define	for_each_pin(idx, pin)		\
  76	for ((pin) = 0; (pin) < ioapics[(idx)].nr_registers; (pin)++)
  77#define	for_each_ioapic_pin(idx, pin)	\
  78	for_each_ioapic((idx))		\
  79		for_each_pin((idx), (pin))
  80#define for_each_irq_pin(entry, head) \
  81	list_for_each_entry(entry, &head, list)
  82
  83static DEFINE_RAW_SPINLOCK(ioapic_lock);
  84static DEFINE_MUTEX(ioapic_mutex);
  85static unsigned int ioapic_dynirq_base;
  86static int ioapic_initialized;
  87
  88struct irq_pin_list {
  89	struct list_head list;
  90	int apic, pin;
  91};
  92
  93struct mp_chip_data {
  94	struct list_head		irq_2_pin;
  95	struct IO_APIC_route_entry	entry;
  96	bool				is_level;
  97	bool				active_low;
  98	bool				isa_irq;
  99	u32 count;
 100};
 101
 102struct mp_ioapic_gsi {
 103	u32 gsi_base;
 104	u32 gsi_end;
 105};
 106
 107static struct ioapic {
 108	/*
 109	 * # of IRQ routing registers
 110	 */
 111	int nr_registers;
 112	/*
 113	 * Saved state during suspend/resume, or while enabling intr-remap.
 114	 */
 115	struct IO_APIC_route_entry *saved_registers;
 116	/* I/O APIC config */
 117	struct mpc_ioapic mp_config;
 118	/* IO APIC gsi routing info */
 119	struct mp_ioapic_gsi  gsi_config;
 120	struct ioapic_domain_cfg irqdomain_cfg;
 121	struct irq_domain *irqdomain;
 122	struct resource *iomem_res;
 123} ioapics[MAX_IO_APICS];
 124
 125#define mpc_ioapic_ver(ioapic_idx)	ioapics[ioapic_idx].mp_config.apicver
 126
 127int mpc_ioapic_id(int ioapic_idx)
 128{
 129	return ioapics[ioapic_idx].mp_config.apicid;
 130}
 131
 132unsigned int mpc_ioapic_addr(int ioapic_idx)
 133{
 134	return ioapics[ioapic_idx].mp_config.apicaddr;
 135}
 136
 137static inline struct mp_ioapic_gsi *mp_ioapic_gsi_routing(int ioapic_idx)
 138{
 139	return &ioapics[ioapic_idx].gsi_config;
 140}
 141
 142static inline int mp_ioapic_pin_count(int ioapic)
 143{
 144	struct mp_ioapic_gsi *gsi_cfg = mp_ioapic_gsi_routing(ioapic);
 145
 146	return gsi_cfg->gsi_end - gsi_cfg->gsi_base + 1;
 147}
 148
 149static inline u32 mp_pin_to_gsi(int ioapic, int pin)
 150{
 151	return mp_ioapic_gsi_routing(ioapic)->gsi_base + pin;
 152}
 153
 154static inline bool mp_is_legacy_irq(int irq)
 155{
 156	return irq >= 0 && irq < nr_legacy_irqs();
 157}
 158
 159static inline struct irq_domain *mp_ioapic_irqdomain(int ioapic)
 160{
 161	return ioapics[ioapic].irqdomain;
 162}
 163
 164int nr_ioapics;
 165
 166/* The one past the highest gsi number used */
 167u32 gsi_top;
 168
 169/* MP IRQ source entries */
 170struct mpc_intsrc mp_irqs[MAX_IRQ_SOURCES];
 171
 172/* # of MP IRQ source entries */
 173int mp_irq_entries;
 174
 175#ifdef CONFIG_EISA
 176int mp_bus_id_to_type[MAX_MP_BUSSES];
 177#endif
 178
 179DECLARE_BITMAP(mp_bus_not_pci, MAX_MP_BUSSES);
 180
 181bool ioapic_is_disabled __ro_after_init;
 182
 183/**
 184 * disable_ioapic_support() - disables ioapic support at runtime
 185 */
 186void disable_ioapic_support(void)
 187{
 188#ifdef CONFIG_PCI
 189	noioapicquirk = 1;
 190	noioapicreroute = -1;
 191#endif
 192	ioapic_is_disabled = true;
 193}
 194
 195static int __init parse_noapic(char *str)
 196{
 197	/* disable IO-APIC */
 198	disable_ioapic_support();
 199	return 0;
 200}
 201early_param("noapic", parse_noapic);
 202
 203/* Will be called in mpparse/ACPI codes for saving IRQ info */
 204void mp_save_irq(struct mpc_intsrc *m)
 205{
 206	int i;
 207
 208	apic_printk(APIC_VERBOSE, "Int: type %d, pol %d, trig %d, bus %02x,"
 209		" IRQ %02x, APIC ID %x, APIC INT %02x\n",
 210		m->irqtype, m->irqflag & 3, (m->irqflag >> 2) & 3, m->srcbus,
 211		m->srcbusirq, m->dstapic, m->dstirq);
 212
 213	for (i = 0; i < mp_irq_entries; i++) {
 214		if (!memcmp(&mp_irqs[i], m, sizeof(*m)))
 215			return;
 216	}
 217
 218	memcpy(&mp_irqs[mp_irq_entries], m, sizeof(*m));
 219	if (++mp_irq_entries == MAX_IRQ_SOURCES)
 220		panic("Max # of irq sources exceeded!!\n");
 221}
 222
 223static void alloc_ioapic_saved_registers(int idx)
 224{
 225	size_t size;
 226
 227	if (ioapics[idx].saved_registers)
 228		return;
 229
 230	size = sizeof(struct IO_APIC_route_entry) * ioapics[idx].nr_registers;
 231	ioapics[idx].saved_registers = kzalloc(size, GFP_KERNEL);
 232	if (!ioapics[idx].saved_registers)
 233		pr_err("IOAPIC %d: suspend/resume impossible!\n", idx);
 234}
 235
 236static void free_ioapic_saved_registers(int idx)
 237{
 238	kfree(ioapics[idx].saved_registers);
 239	ioapics[idx].saved_registers = NULL;
 240}
 241
 242int __init arch_early_ioapic_init(void)
 243{
 244	int i;
 245
 246	if (!nr_legacy_irqs())
 247		io_apic_irqs = ~0UL;
 248
 249	for_each_ioapic(i)
 250		alloc_ioapic_saved_registers(i);
 251
 252	return 0;
 253}
 254
 255struct io_apic {
 256	unsigned int index;
 257	unsigned int unused[3];
 258	unsigned int data;
 259	unsigned int unused2[11];
 260	unsigned int eoi;
 261};
 262
 263static __attribute_const__ struct io_apic __iomem *io_apic_base(int idx)
 264{
 265	return (void __iomem *) __fix_to_virt(FIX_IO_APIC_BASE_0 + idx)
 266		+ (mpc_ioapic_addr(idx) & ~PAGE_MASK);
 267}
 268
 269static inline void io_apic_eoi(unsigned int apic, unsigned int vector)
 270{
 271	struct io_apic __iomem *io_apic = io_apic_base(apic);
 272	writel(vector, &io_apic->eoi);
 273}
 274
 275unsigned int native_io_apic_read(unsigned int apic, unsigned int reg)
 276{
 277	struct io_apic __iomem *io_apic = io_apic_base(apic);
 278	writel(reg, &io_apic->index);
 279	return readl(&io_apic->data);
 280}
 281
 282static void io_apic_write(unsigned int apic, unsigned int reg,
 283			  unsigned int value)
 284{
 285	struct io_apic __iomem *io_apic = io_apic_base(apic);
 286
 287	writel(reg, &io_apic->index);
 288	writel(value, &io_apic->data);
 289}
 290
 291static struct IO_APIC_route_entry __ioapic_read_entry(int apic, int pin)
 292{
 293	struct IO_APIC_route_entry entry;
 294
 295	entry.w1 = io_apic_read(apic, 0x10 + 2 * pin);
 296	entry.w2 = io_apic_read(apic, 0x11 + 2 * pin);
 297
 298	return entry;
 299}
 300
 301static struct IO_APIC_route_entry ioapic_read_entry(int apic, int pin)
 302{
 303	struct IO_APIC_route_entry entry;
 304	unsigned long flags;
 305
 306	raw_spin_lock_irqsave(&ioapic_lock, flags);
 307	entry = __ioapic_read_entry(apic, pin);
 308	raw_spin_unlock_irqrestore(&ioapic_lock, flags);
 309
 310	return entry;
 311}
 312
 313/*
 314 * When we write a new IO APIC routing entry, we need to write the high
 315 * word first! If the mask bit in the low word is clear, we will enable
 316 * the interrupt, and we need to make sure the entry is fully populated
 317 * before that happens.
 318 */
 319static void __ioapic_write_entry(int apic, int pin, struct IO_APIC_route_entry e)
 320{
 321	io_apic_write(apic, 0x11 + 2*pin, e.w2);
 322	io_apic_write(apic, 0x10 + 2*pin, e.w1);
 323}
 324
 325static void ioapic_write_entry(int apic, int pin, struct IO_APIC_route_entry e)
 326{
 327	unsigned long flags;
 328
 329	raw_spin_lock_irqsave(&ioapic_lock, flags);
 330	__ioapic_write_entry(apic, pin, e);
 331	raw_spin_unlock_irqrestore(&ioapic_lock, flags);
 332}
 333
 334/*
 335 * When we mask an IO APIC routing entry, we need to write the low
 336 * word first, in order to set the mask bit before we change the
 337 * high bits!
 338 */
 339static void ioapic_mask_entry(int apic, int pin)
 340{
 341	struct IO_APIC_route_entry e = { .masked = true };
 342	unsigned long flags;
 343
 344	raw_spin_lock_irqsave(&ioapic_lock, flags);
 345	io_apic_write(apic, 0x10 + 2*pin, e.w1);
 346	io_apic_write(apic, 0x11 + 2*pin, e.w2);
 347	raw_spin_unlock_irqrestore(&ioapic_lock, flags);
 348}
 349
 350/*
 351 * The common case is 1:1 IRQ<->pin mappings. Sometimes there are
 352 * shared ISA-space IRQs, so we have to support them. We are super
 353 * fast in the common case, and fast for shared ISA-space IRQs.
 354 */
 355static int __add_pin_to_irq_node(struct mp_chip_data *data,
 356				 int node, int apic, int pin)
 357{
 358	struct irq_pin_list *entry;
 359
 360	/* don't allow duplicates */
 361	for_each_irq_pin(entry, data->irq_2_pin)
 362		if (entry->apic == apic && entry->pin == pin)
 363			return 0;
 364
 365	entry = kzalloc_node(sizeof(struct irq_pin_list), GFP_ATOMIC, node);
 366	if (!entry) {
 367		pr_err("can not alloc irq_pin_list (%d,%d,%d)\n",
 368		       node, apic, pin);
 369		return -ENOMEM;
 370	}
 371	entry->apic = apic;
 372	entry->pin = pin;
 373	list_add_tail(&entry->list, &data->irq_2_pin);
 374
 375	return 0;
 376}
 377
 378static void __remove_pin_from_irq(struct mp_chip_data *data, int apic, int pin)
 379{
 380	struct irq_pin_list *tmp, *entry;
 381
 382	list_for_each_entry_safe(entry, tmp, &data->irq_2_pin, list)
 383		if (entry->apic == apic && entry->pin == pin) {
 384			list_del(&entry->list);
 385			kfree(entry);
 386			return;
 387		}
 388}
 389
 390static void add_pin_to_irq_node(struct mp_chip_data *data,
 391				int node, int apic, int pin)
 392{
 393	if (__add_pin_to_irq_node(data, node, apic, pin))
 394		panic("IO-APIC: failed to add irq-pin. Can not proceed\n");
 395}
 396
 397/*
 398 * Reroute an IRQ to a different pin.
 399 */
 400static void __init replace_pin_at_irq_node(struct mp_chip_data *data, int node,
 401					   int oldapic, int oldpin,
 402					   int newapic, int newpin)
 403{
 404	struct irq_pin_list *entry;
 405
 406	for_each_irq_pin(entry, data->irq_2_pin) {
 407		if (entry->apic == oldapic && entry->pin == oldpin) {
 408			entry->apic = newapic;
 409			entry->pin = newpin;
 410			/* every one is different, right? */
 411			return;
 412		}
 413	}
 414
 415	/* old apic/pin didn't exist, so just add new ones */
 416	add_pin_to_irq_node(data, node, newapic, newpin);
 417}
 418
 419static void io_apic_modify_irq(struct mp_chip_data *data, bool masked,
 420			       void (*final)(struct irq_pin_list *entry))
 421{
 422	struct irq_pin_list *entry;
 423
 424	data->entry.masked = masked;
 425
 426	for_each_irq_pin(entry, data->irq_2_pin) {
 427		io_apic_write(entry->apic, 0x10 + 2 * entry->pin, data->entry.w1);
 428		if (final)
 429			final(entry);
 430	}
 431}
 432
 433static void io_apic_sync(struct irq_pin_list *entry)
 434{
 435	/*
 436	 * Synchronize the IO-APIC and the CPU by doing
 437	 * a dummy read from the IO-APIC
 438	 */
 439	struct io_apic __iomem *io_apic;
 440
 441	io_apic = io_apic_base(entry->apic);
 442	readl(&io_apic->data);
 443}
 444
 445static void mask_ioapic_irq(struct irq_data *irq_data)
 446{
 447	struct mp_chip_data *data = irq_data->chip_data;
 448	unsigned long flags;
 449
 450	raw_spin_lock_irqsave(&ioapic_lock, flags);
 451	io_apic_modify_irq(data, true, &io_apic_sync);
 452	raw_spin_unlock_irqrestore(&ioapic_lock, flags);
 453}
 454
 455static void __unmask_ioapic(struct mp_chip_data *data)
 456{
 457	io_apic_modify_irq(data, false, NULL);
 458}
 459
 460static void unmask_ioapic_irq(struct irq_data *irq_data)
 461{
 462	struct mp_chip_data *data = irq_data->chip_data;
 463	unsigned long flags;
 464
 465	raw_spin_lock_irqsave(&ioapic_lock, flags);
 466	__unmask_ioapic(data);
 467	raw_spin_unlock_irqrestore(&ioapic_lock, flags);
 468}
 469
 470/*
 471 * IO-APIC versions below 0x20 don't support EOI register.
 472 * For the record, here is the information about various versions:
 473 *     0Xh     82489DX
 474 *     1Xh     I/OAPIC or I/O(x)APIC which are not PCI 2.2 Compliant
 475 *     2Xh     I/O(x)APIC which is PCI 2.2 Compliant
 476 *     30h-FFh Reserved
 477 *
 478 * Some of the Intel ICH Specs (ICH2 to ICH5) documents the io-apic
 479 * version as 0x2. This is an error with documentation and these ICH chips
 480 * use io-apic's of version 0x20.
 481 *
 482 * For IO-APIC's with EOI register, we use that to do an explicit EOI.
 483 * Otherwise, we simulate the EOI message manually by changing the trigger
 484 * mode to edge and then back to level, with RTE being masked during this.
 485 */
 486static void __eoi_ioapic_pin(int apic, int pin, int vector)
 487{
 488	if (mpc_ioapic_ver(apic) >= 0x20) {
 489		io_apic_eoi(apic, vector);
 490	} else {
 491		struct IO_APIC_route_entry entry, entry1;
 492
 493		entry = entry1 = __ioapic_read_entry(apic, pin);
 494
 495		/*
 496		 * Mask the entry and change the trigger mode to edge.
 497		 */
 498		entry1.masked = true;
 499		entry1.is_level = false;
 500
 501		__ioapic_write_entry(apic, pin, entry1);
 502
 503		/*
 504		 * Restore the previous level triggered entry.
 505		 */
 506		__ioapic_write_entry(apic, pin, entry);
 507	}
 508}
 509
 510static void eoi_ioapic_pin(int vector, struct mp_chip_data *data)
 511{
 512	unsigned long flags;
 513	struct irq_pin_list *entry;
 514
 515	raw_spin_lock_irqsave(&ioapic_lock, flags);
 516	for_each_irq_pin(entry, data->irq_2_pin)
 517		__eoi_ioapic_pin(entry->apic, entry->pin, vector);
 518	raw_spin_unlock_irqrestore(&ioapic_lock, flags);
 519}
 520
 521static void clear_IO_APIC_pin(unsigned int apic, unsigned int pin)
 522{
 523	struct IO_APIC_route_entry entry;
 524
 525	/* Check delivery_mode to be sure we're not clearing an SMI pin */
 526	entry = ioapic_read_entry(apic, pin);
 527	if (entry.delivery_mode == APIC_DELIVERY_MODE_SMI)
 528		return;
 529
 530	/*
 531	 * Make sure the entry is masked and re-read the contents to check
 532	 * if it is a level triggered pin and if the remote-IRR is set.
 533	 */
 534	if (!entry.masked) {
 535		entry.masked = true;
 536		ioapic_write_entry(apic, pin, entry);
 537		entry = ioapic_read_entry(apic, pin);
 538	}
 539
 540	if (entry.irr) {
 541		unsigned long flags;
 542
 543		/*
 544		 * Make sure the trigger mode is set to level. Explicit EOI
 545		 * doesn't clear the remote-IRR if the trigger mode is not
 546		 * set to level.
 547		 */
 548		if (!entry.is_level) {
 549			entry.is_level = true;
 550			ioapic_write_entry(apic, pin, entry);
 551		}
 552		raw_spin_lock_irqsave(&ioapic_lock, flags);
 553		__eoi_ioapic_pin(apic, pin, entry.vector);
 554		raw_spin_unlock_irqrestore(&ioapic_lock, flags);
 555	}
 556
 557	/*
 558	 * Clear the rest of the bits in the IO-APIC RTE except for the mask
 559	 * bit.
 560	 */
 561	ioapic_mask_entry(apic, pin);
 562	entry = ioapic_read_entry(apic, pin);
 563	if (entry.irr)
 564		pr_err("Unable to reset IRR for apic: %d, pin :%d\n",
 565		       mpc_ioapic_id(apic), pin);
 566}
 567
 568void clear_IO_APIC (void)
 569{
 570	int apic, pin;
 571
 572	for_each_ioapic_pin(apic, pin)
 573		clear_IO_APIC_pin(apic, pin);
 574}
 575
 576#ifdef CONFIG_X86_32
 577/*
 578 * support for broken MP BIOSs, enables hand-redirection of PIRQ0-7 to
 579 * specific CPU-side IRQs.
 580 */
 581
 582#define MAX_PIRQS 8
 583static int pirq_entries[MAX_PIRQS] = {
 584	[0 ... MAX_PIRQS - 1] = -1
 585};
 586
 587static int __init ioapic_pirq_setup(char *str)
 588{
 589	int i, max;
 590	int ints[MAX_PIRQS+1];
 591
 592	get_options(str, ARRAY_SIZE(ints), ints);
 593
 594	apic_printk(APIC_VERBOSE, KERN_INFO
 595			"PIRQ redirection, working around broken MP-BIOS.\n");
 596	max = MAX_PIRQS;
 597	if (ints[0] < MAX_PIRQS)
 598		max = ints[0];
 599
 600	for (i = 0; i < max; i++) {
 601		apic_printk(APIC_VERBOSE, KERN_DEBUG
 602				"... PIRQ%d -> IRQ %d\n", i, ints[i+1]);
 603		/*
 604		 * PIRQs are mapped upside down, usually.
 605		 */
 606		pirq_entries[MAX_PIRQS-i-1] = ints[i+1];
 607	}
 608	return 1;
 609}
 610
 611__setup("pirq=", ioapic_pirq_setup);
 612#endif /* CONFIG_X86_32 */
 613
 614/*
 615 * Saves all the IO-APIC RTE's
 616 */
 617int save_ioapic_entries(void)
 618{
 619	int apic, pin;
 620	int err = 0;
 621
 622	for_each_ioapic(apic) {
 623		if (!ioapics[apic].saved_registers) {
 624			err = -ENOMEM;
 625			continue;
 626		}
 627
 628		for_each_pin(apic, pin)
 629			ioapics[apic].saved_registers[pin] =
 630				ioapic_read_entry(apic, pin);
 631	}
 632
 633	return err;
 634}
 635
 636/*
 637 * Mask all IO APIC entries.
 638 */
 639void mask_ioapic_entries(void)
 640{
 641	int apic, pin;
 642
 643	for_each_ioapic(apic) {
 644		if (!ioapics[apic].saved_registers)
 645			continue;
 646
 647		for_each_pin(apic, pin) {
 648			struct IO_APIC_route_entry entry;
 649
 650			entry = ioapics[apic].saved_registers[pin];
 651			if (!entry.masked) {
 652				entry.masked = true;
 653				ioapic_write_entry(apic, pin, entry);
 654			}
 655		}
 656	}
 657}
 658
 659/*
 660 * Restore IO APIC entries which was saved in the ioapic structure.
 661 */
 662int restore_ioapic_entries(void)
 663{
 664	int apic, pin;
 665
 666	for_each_ioapic(apic) {
 667		if (!ioapics[apic].saved_registers)
 668			continue;
 669
 670		for_each_pin(apic, pin)
 671			ioapic_write_entry(apic, pin,
 672					   ioapics[apic].saved_registers[pin]);
 673	}
 674	return 0;
 675}
 676
 677/*
 678 * Find the IRQ entry number of a certain pin.
 679 */
 680static int find_irq_entry(int ioapic_idx, int pin, int type)
 681{
 682	int i;
 683
 684	for (i = 0; i < mp_irq_entries; i++)
 685		if (mp_irqs[i].irqtype == type &&
 686		    (mp_irqs[i].dstapic == mpc_ioapic_id(ioapic_idx) ||
 687		     mp_irqs[i].dstapic == MP_APIC_ALL) &&
 688		    mp_irqs[i].dstirq == pin)
 689			return i;
 690
 691	return -1;
 692}
 693
 694/*
 695 * Find the pin to which IRQ[irq] (ISA) is connected
 696 */
 697static int __init find_isa_irq_pin(int irq, int type)
 698{
 699	int i;
 700
 701	for (i = 0; i < mp_irq_entries; i++) {
 702		int lbus = mp_irqs[i].srcbus;
 703
 704		if (test_bit(lbus, mp_bus_not_pci) &&
 705		    (mp_irqs[i].irqtype == type) &&
 706		    (mp_irqs[i].srcbusirq == irq))
 707
 708			return mp_irqs[i].dstirq;
 709	}
 710	return -1;
 711}
 712
 713static int __init find_isa_irq_apic(int irq, int type)
 714{
 715	int i;
 716
 717	for (i = 0; i < mp_irq_entries; i++) {
 718		int lbus = mp_irqs[i].srcbus;
 719
 720		if (test_bit(lbus, mp_bus_not_pci) &&
 721		    (mp_irqs[i].irqtype == type) &&
 722		    (mp_irqs[i].srcbusirq == irq))
 723			break;
 724	}
 725
 726	if (i < mp_irq_entries) {
 727		int ioapic_idx;
 728
 729		for_each_ioapic(ioapic_idx)
 730			if (mpc_ioapic_id(ioapic_idx) == mp_irqs[i].dstapic)
 731				return ioapic_idx;
 732	}
 733
 734	return -1;
 735}
 736
 737static bool irq_active_low(int idx)
 738{
 739	int bus = mp_irqs[idx].srcbus;
 740
 741	/*
 742	 * Determine IRQ line polarity (high active or low active):
 743	 */
 744	switch (mp_irqs[idx].irqflag & MP_IRQPOL_MASK) {
 745	case MP_IRQPOL_DEFAULT:
 746		/*
 747		 * Conforms to spec, ie. bus-type dependent polarity.  PCI
 748		 * defaults to low active. [E]ISA defaults to high active.
 749		 */
 750		return !test_bit(bus, mp_bus_not_pci);
 751	case MP_IRQPOL_ACTIVE_HIGH:
 752		return false;
 753	case MP_IRQPOL_RESERVED:
 754		pr_warn("IOAPIC: Invalid polarity: 2, defaulting to low\n");
 755		fallthrough;
 756	case MP_IRQPOL_ACTIVE_LOW:
 757	default: /* Pointless default required due to do gcc stupidity */
 758		return true;
 759	}
 760}
 761
 762#ifdef CONFIG_EISA
 763/*
 764 * EISA Edge/Level control register, ELCR
 765 */
 766static bool EISA_ELCR(unsigned int irq)
 767{
 768	if (irq < nr_legacy_irqs()) {
 769		unsigned int port = PIC_ELCR1 + (irq >> 3);
 770		return (inb(port) >> (irq & 7)) & 1;
 771	}
 772	apic_printk(APIC_VERBOSE, KERN_INFO
 773			"Broken MPtable reports ISA irq %d\n", irq);
 774	return false;
 775}
 776
 777/*
 778 * EISA interrupts are always active high and can be edge or level
 779 * triggered depending on the ELCR value.  If an interrupt is listed as
 780 * EISA conforming in the MP table, that means its trigger type must be
 781 * read in from the ELCR.
 782 */
 783static bool eisa_irq_is_level(int idx, int bus, bool level)
 784{
 785	switch (mp_bus_id_to_type[bus]) {
 786	case MP_BUS_PCI:
 787	case MP_BUS_ISA:
 788		return level;
 789	case MP_BUS_EISA:
 790		return EISA_ELCR(mp_irqs[idx].srcbusirq);
 791	}
 792	pr_warn("IOAPIC: Invalid srcbus: %d defaulting to level\n", bus);
 793	return true;
 794}
 795#else
 796static inline int eisa_irq_is_level(int idx, int bus, bool level)
 797{
 798	return level;
 799}
 800#endif
 801
 802static bool irq_is_level(int idx)
 803{
 804	int bus = mp_irqs[idx].srcbus;
 805	bool level;
 806
 807	/*
 808	 * Determine IRQ trigger mode (edge or level sensitive):
 809	 */
 810	switch (mp_irqs[idx].irqflag & MP_IRQTRIG_MASK) {
 811	case MP_IRQTRIG_DEFAULT:
 812		/*
 813		 * Conforms to spec, ie. bus-type dependent trigger
 814		 * mode. PCI defaults to level, ISA to edge.
 815		 */
 816		level = !test_bit(bus, mp_bus_not_pci);
 817		/* Take EISA into account */
 818		return eisa_irq_is_level(idx, bus, level);
 819	case MP_IRQTRIG_EDGE:
 820		return false;
 821	case MP_IRQTRIG_RESERVED:
 822		pr_warn("IOAPIC: Invalid trigger mode 2 defaulting to level\n");
 823		fallthrough;
 824	case MP_IRQTRIG_LEVEL:
 825	default: /* Pointless default required due to do gcc stupidity */
 826		return true;
 827	}
 828}
 829
 830static int __acpi_get_override_irq(u32 gsi, bool *trigger, bool *polarity)
 831{
 832	int ioapic, pin, idx;
 833
 834	if (ioapic_is_disabled)
 835		return -1;
 836
 837	ioapic = mp_find_ioapic(gsi);
 838	if (ioapic < 0)
 839		return -1;
 840
 841	pin = mp_find_ioapic_pin(ioapic, gsi);
 842	if (pin < 0)
 843		return -1;
 844
 845	idx = find_irq_entry(ioapic, pin, mp_INT);
 846	if (idx < 0)
 847		return -1;
 848
 849	*trigger = irq_is_level(idx);
 850	*polarity = irq_active_low(idx);
 851	return 0;
 852}
 853
 854#ifdef CONFIG_ACPI
 855int acpi_get_override_irq(u32 gsi, int *is_level, int *active_low)
 856{
 857	*is_level = *active_low = 0;
 858	return __acpi_get_override_irq(gsi, (bool *)is_level,
 859				       (bool *)active_low);
 860}
 861#endif
 862
 863void ioapic_set_alloc_attr(struct irq_alloc_info *info, int node,
 864			   int trigger, int polarity)
 865{
 866	init_irq_alloc_info(info, NULL);
 867	info->type = X86_IRQ_ALLOC_TYPE_IOAPIC;
 868	info->ioapic.node = node;
 869	info->ioapic.is_level = trigger;
 870	info->ioapic.active_low = polarity;
 871	info->ioapic.valid = 1;
 872}
 873
 874static void ioapic_copy_alloc_attr(struct irq_alloc_info *dst,
 875				   struct irq_alloc_info *src,
 876				   u32 gsi, int ioapic_idx, int pin)
 877{
 878	bool level, pol_low;
 879
 880	copy_irq_alloc_info(dst, src);
 881	dst->type = X86_IRQ_ALLOC_TYPE_IOAPIC;
 882	dst->devid = mpc_ioapic_id(ioapic_idx);
 883	dst->ioapic.pin = pin;
 884	dst->ioapic.valid = 1;
 885	if (src && src->ioapic.valid) {
 886		dst->ioapic.node = src->ioapic.node;
 887		dst->ioapic.is_level = src->ioapic.is_level;
 888		dst->ioapic.active_low = src->ioapic.active_low;
 889	} else {
 890		dst->ioapic.node = NUMA_NO_NODE;
 891		if (__acpi_get_override_irq(gsi, &level, &pol_low) >= 0) {
 892			dst->ioapic.is_level = level;
 893			dst->ioapic.active_low = pol_low;
 894		} else {
 895			/*
 896			 * PCI interrupts are always active low level
 897			 * triggered.
 898			 */
 899			dst->ioapic.is_level = true;
 900			dst->ioapic.active_low = true;
 901		}
 902	}
 903}
 904
 905static int ioapic_alloc_attr_node(struct irq_alloc_info *info)
 906{
 907	return (info && info->ioapic.valid) ? info->ioapic.node : NUMA_NO_NODE;
 908}
 909
 910static void mp_register_handler(unsigned int irq, bool level)
 911{
 912	irq_flow_handler_t hdl;
 913	bool fasteoi;
 914
 915	if (level) {
 916		irq_set_status_flags(irq, IRQ_LEVEL);
 917		fasteoi = true;
 918	} else {
 919		irq_clear_status_flags(irq, IRQ_LEVEL);
 920		fasteoi = false;
 921	}
 922
 923	hdl = fasteoi ? handle_fasteoi_irq : handle_edge_irq;
 924	__irq_set_handler(irq, hdl, 0, fasteoi ? "fasteoi" : "edge");
 925}
 926
 927static bool mp_check_pin_attr(int irq, struct irq_alloc_info *info)
 928{
 929	struct mp_chip_data *data = irq_get_chip_data(irq);
 930
 931	/*
 932	 * setup_IO_APIC_irqs() programs all legacy IRQs with default trigger
 933	 * and polarity attributes. So allow the first user to reprogram the
 934	 * pin with real trigger and polarity attributes.
 935	 */
 936	if (irq < nr_legacy_irqs() && data->count == 1) {
 937		if (info->ioapic.is_level != data->is_level)
 938			mp_register_handler(irq, info->ioapic.is_level);
 939		data->entry.is_level = data->is_level = info->ioapic.is_level;
 940		data->entry.active_low = data->active_low = info->ioapic.active_low;
 941	}
 942
 943	return data->is_level == info->ioapic.is_level &&
 944	       data->active_low == info->ioapic.active_low;
 945}
 946
 947static int alloc_irq_from_domain(struct irq_domain *domain, int ioapic, u32 gsi,
 948				 struct irq_alloc_info *info)
 949{
 950	bool legacy = false;
 951	int irq = -1;
 952	int type = ioapics[ioapic].irqdomain_cfg.type;
 953
 954	switch (type) {
 955	case IOAPIC_DOMAIN_LEGACY:
 956		/*
 957		 * Dynamically allocate IRQ number for non-ISA IRQs in the first
 958		 * 16 GSIs on some weird platforms.
 959		 */
 960		if (!ioapic_initialized || gsi >= nr_legacy_irqs())
 961			irq = gsi;
 962		legacy = mp_is_legacy_irq(irq);
 963		break;
 964	case IOAPIC_DOMAIN_STRICT:
 965		irq = gsi;
 966		break;
 967	case IOAPIC_DOMAIN_DYNAMIC:
 968		break;
 969	default:
 970		WARN(1, "ioapic: unknown irqdomain type %d\n", type);
 971		return -1;
 972	}
 973
 974	return __irq_domain_alloc_irqs(domain, irq, 1,
 975				       ioapic_alloc_attr_node(info),
 976				       info, legacy, NULL);
 977}
 978
 979/*
 980 * Need special handling for ISA IRQs because there may be multiple IOAPIC pins
 981 * sharing the same ISA IRQ number and irqdomain only supports 1:1 mapping
 982 * between IOAPIC pin and IRQ number. A typical IOAPIC has 24 pins, pin 0-15 are
 983 * used for legacy IRQs and pin 16-23 are used for PCI IRQs (PIRQ A-H).
 984 * When ACPI is disabled, only legacy IRQ numbers (IRQ0-15) are available, and
 985 * some BIOSes may use MP Interrupt Source records to override IRQ numbers for
 986 * PIRQs instead of reprogramming the interrupt routing logic. Thus there may be
 987 * multiple pins sharing the same legacy IRQ number when ACPI is disabled.
 988 */
 989static int alloc_isa_irq_from_domain(struct irq_domain *domain,
 990				     int irq, int ioapic, int pin,
 991				     struct irq_alloc_info *info)
 992{
 993	struct mp_chip_data *data;
 994	struct irq_data *irq_data = irq_get_irq_data(irq);
 995	int node = ioapic_alloc_attr_node(info);
 996
 997	/*
 998	 * Legacy ISA IRQ has already been allocated, just add pin to
 999	 * the pin list associated with this IRQ and program the IOAPIC
1000	 * entry.
1001	 */
1002	if (irq_data && irq_data->parent_data) {
1003		if (!mp_check_pin_attr(irq, info))
1004			return -EBUSY;
1005		if (__add_pin_to_irq_node(irq_data->chip_data, node, ioapic,
1006					  info->ioapic.pin))
1007			return -ENOMEM;
1008	} else {
1009		info->flags |= X86_IRQ_ALLOC_LEGACY;
1010		irq = __irq_domain_alloc_irqs(domain, irq, 1, node, info, true,
1011					      NULL);
1012		if (irq >= 0) {
1013			irq_data = irq_domain_get_irq_data(domain, irq);
1014			data = irq_data->chip_data;
1015			data->isa_irq = true;
1016		}
1017	}
1018
1019	return irq;
1020}
1021
1022static int mp_map_pin_to_irq(u32 gsi, int idx, int ioapic, int pin,
1023			     unsigned int flags, struct irq_alloc_info *info)
1024{
1025	int irq;
1026	bool legacy = false;
1027	struct irq_alloc_info tmp;
1028	struct mp_chip_data *data;
1029	struct irq_domain *domain = mp_ioapic_irqdomain(ioapic);
1030
1031	if (!domain)
1032		return -ENOSYS;
1033
1034	if (idx >= 0 && test_bit(mp_irqs[idx].srcbus, mp_bus_not_pci)) {
1035		irq = mp_irqs[idx].srcbusirq;
1036		legacy = mp_is_legacy_irq(irq);
1037		/*
1038		 * IRQ2 is unusable for historical reasons on systems which
1039		 * have a legacy PIC. See the comment vs. IRQ2 further down.
1040		 *
1041		 * If this gets removed at some point then the related code
1042		 * in lapic_assign_system_vectors() needs to be adjusted as
1043		 * well.
1044		 */
1045		if (legacy && irq == PIC_CASCADE_IR)
1046			return -EINVAL;
1047	}
1048
1049	mutex_lock(&ioapic_mutex);
1050	if (!(flags & IOAPIC_MAP_ALLOC)) {
1051		if (!legacy) {
1052			irq = irq_find_mapping(domain, pin);
1053			if (irq == 0)
1054				irq = -ENOENT;
1055		}
1056	} else {
1057		ioapic_copy_alloc_attr(&tmp, info, gsi, ioapic, pin);
1058		if (legacy)
1059			irq = alloc_isa_irq_from_domain(domain, irq,
1060							ioapic, pin, &tmp);
1061		else if ((irq = irq_find_mapping(domain, pin)) == 0)
1062			irq = alloc_irq_from_domain(domain, ioapic, gsi, &tmp);
1063		else if (!mp_check_pin_attr(irq, &tmp))
1064			irq = -EBUSY;
1065		if (irq >= 0) {
1066			data = irq_get_chip_data(irq);
1067			data->count++;
1068		}
1069	}
1070	mutex_unlock(&ioapic_mutex);
1071
1072	return irq;
1073}
1074
1075static int pin_2_irq(int idx, int ioapic, int pin, unsigned int flags)
1076{
1077	u32 gsi = mp_pin_to_gsi(ioapic, pin);
1078
1079	/*
1080	 * Debugging check, we are in big trouble if this message pops up!
1081	 */
1082	if (mp_irqs[idx].dstirq != pin)
1083		pr_err("broken BIOS or MPTABLE parser, ayiee!!\n");
1084
1085#ifdef CONFIG_X86_32
1086	/*
1087	 * PCI IRQ command line redirection. Yes, limits are hardcoded.
1088	 */
1089	if ((pin >= 16) && (pin <= 23)) {
1090		if (pirq_entries[pin-16] != -1) {
1091			if (!pirq_entries[pin-16]) {
1092				apic_printk(APIC_VERBOSE, KERN_DEBUG
1093						"disabling PIRQ%d\n", pin-16);
1094			} else {
1095				int irq = pirq_entries[pin-16];
1096				apic_printk(APIC_VERBOSE, KERN_DEBUG
1097						"using PIRQ%d -> IRQ %d\n",
1098						pin-16, irq);
1099				return irq;
1100			}
1101		}
1102	}
1103#endif
1104
1105	return  mp_map_pin_to_irq(gsi, idx, ioapic, pin, flags, NULL);
1106}
1107
1108int mp_map_gsi_to_irq(u32 gsi, unsigned int flags, struct irq_alloc_info *info)
1109{
1110	int ioapic, pin, idx;
1111
1112	ioapic = mp_find_ioapic(gsi);
1113	if (ioapic < 0)
1114		return -ENODEV;
1115
1116	pin = mp_find_ioapic_pin(ioapic, gsi);
1117	idx = find_irq_entry(ioapic, pin, mp_INT);
1118	if ((flags & IOAPIC_MAP_CHECK) && idx < 0)
1119		return -ENODEV;
1120
1121	return mp_map_pin_to_irq(gsi, idx, ioapic, pin, flags, info);
1122}
1123
1124void mp_unmap_irq(int irq)
1125{
1126	struct irq_data *irq_data = irq_get_irq_data(irq);
1127	struct mp_chip_data *data;
1128
1129	if (!irq_data || !irq_data->domain)
1130		return;
1131
1132	data = irq_data->chip_data;
1133	if (!data || data->isa_irq)
1134		return;
1135
1136	mutex_lock(&ioapic_mutex);
1137	if (--data->count == 0)
1138		irq_domain_free_irqs(irq, 1);
1139	mutex_unlock(&ioapic_mutex);
1140}
1141
1142/*
1143 * Find a specific PCI IRQ entry.
1144 * Not an __init, possibly needed by modules
1145 */
1146int IO_APIC_get_PCI_irq_vector(int bus, int slot, int pin)
1147{
1148	int irq, i, best_ioapic = -1, best_idx = -1;
1149
1150	apic_printk(APIC_DEBUG,
1151		    "querying PCI -> IRQ mapping bus:%d, slot:%d, pin:%d.\n",
1152		    bus, slot, pin);
1153	if (test_bit(bus, mp_bus_not_pci)) {
1154		apic_printk(APIC_VERBOSE,
1155			    "PCI BIOS passed nonexistent PCI bus %d!\n", bus);
1156		return -1;
1157	}
1158
1159	for (i = 0; i < mp_irq_entries; i++) {
1160		int lbus = mp_irqs[i].srcbus;
1161		int ioapic_idx, found = 0;
1162
1163		if (bus != lbus || mp_irqs[i].irqtype != mp_INT ||
1164		    slot != ((mp_irqs[i].srcbusirq >> 2) & 0x1f))
1165			continue;
1166
1167		for_each_ioapic(ioapic_idx)
1168			if (mpc_ioapic_id(ioapic_idx) == mp_irqs[i].dstapic ||
1169			    mp_irqs[i].dstapic == MP_APIC_ALL) {
1170				found = 1;
1171				break;
1172			}
1173		if (!found)
1174			continue;
1175
1176		/* Skip ISA IRQs */
1177		irq = pin_2_irq(i, ioapic_idx, mp_irqs[i].dstirq, 0);
1178		if (irq > 0 && !IO_APIC_IRQ(irq))
1179			continue;
1180
1181		if (pin == (mp_irqs[i].srcbusirq & 3)) {
1182			best_idx = i;
1183			best_ioapic = ioapic_idx;
1184			goto out;
1185		}
1186
1187		/*
1188		 * Use the first all-but-pin matching entry as a
1189		 * best-guess fuzzy result for broken mptables.
1190		 */
1191		if (best_idx < 0) {
1192			best_idx = i;
1193			best_ioapic = ioapic_idx;
1194		}
1195	}
1196	if (best_idx < 0)
1197		return -1;
1198
1199out:
1200	return pin_2_irq(best_idx, best_ioapic, mp_irqs[best_idx].dstirq,
1201			 IOAPIC_MAP_ALLOC);
1202}
1203EXPORT_SYMBOL(IO_APIC_get_PCI_irq_vector);
1204
1205static struct irq_chip ioapic_chip, ioapic_ir_chip;
1206
1207static void __init setup_IO_APIC_irqs(void)
1208{
1209	unsigned int ioapic, pin;
1210	int idx;
1211
1212	apic_printk(APIC_VERBOSE, KERN_DEBUG "init IO_APIC IRQs\n");
1213
1214	for_each_ioapic_pin(ioapic, pin) {
1215		idx = find_irq_entry(ioapic, pin, mp_INT);
1216		if (idx < 0)
1217			apic_printk(APIC_VERBOSE,
1218				    KERN_DEBUG " apic %d pin %d not connected\n",
1219				    mpc_ioapic_id(ioapic), pin);
1220		else
1221			pin_2_irq(idx, ioapic, pin,
1222				  ioapic ? 0 : IOAPIC_MAP_ALLOC);
1223	}
1224}
1225
1226void ioapic_zap_locks(void)
1227{
1228	raw_spin_lock_init(&ioapic_lock);
1229}
1230
1231static void io_apic_print_entries(unsigned int apic, unsigned int nr_entries)
1232{
1233	struct IO_APIC_route_entry entry;
1234	char buf[256];
1235	int i;
1236
1237	printk(KERN_DEBUG "IOAPIC %d:\n", apic);
1238	for (i = 0; i <= nr_entries; i++) {
1239		entry = ioapic_read_entry(apic, i);
1240		snprintf(buf, sizeof(buf),
1241			 " pin%02x, %s, %s, %s, V(%02X), IRR(%1d), S(%1d)",
1242			 i,
1243			 entry.masked ? "disabled" : "enabled ",
1244			 entry.is_level ? "level" : "edge ",
1245			 entry.active_low ? "low " : "high",
1246			 entry.vector, entry.irr, entry.delivery_status);
1247		if (entry.ir_format) {
1248			printk(KERN_DEBUG "%s, remapped, I(%04X),  Z(%X)\n",
1249			       buf,
1250			       (entry.ir_index_15 << 15) | entry.ir_index_0_14,
1251				entry.ir_zero);
1252		} else {
1253			printk(KERN_DEBUG "%s, %s, D(%02X%02X), M(%1d)\n", buf,
1254			       entry.dest_mode_logical ? "logical " : "physical",
1255			       entry.virt_destid_8_14, entry.destid_0_7,
1256			       entry.delivery_mode);
1257		}
1258	}
1259}
1260
1261static void __init print_IO_APIC(int ioapic_idx)
1262{
1263	union IO_APIC_reg_00 reg_00;
1264	union IO_APIC_reg_01 reg_01;
1265	union IO_APIC_reg_02 reg_02;
1266	union IO_APIC_reg_03 reg_03;
1267	unsigned long flags;
1268
1269	raw_spin_lock_irqsave(&ioapic_lock, flags);
1270	reg_00.raw = io_apic_read(ioapic_idx, 0);
1271	reg_01.raw = io_apic_read(ioapic_idx, 1);
1272	if (reg_01.bits.version >= 0x10)
1273		reg_02.raw = io_apic_read(ioapic_idx, 2);
1274	if (reg_01.bits.version >= 0x20)
1275		reg_03.raw = io_apic_read(ioapic_idx, 3);
1276	raw_spin_unlock_irqrestore(&ioapic_lock, flags);
1277
1278	printk(KERN_DEBUG "IO APIC #%d......\n", mpc_ioapic_id(ioapic_idx));
1279	printk(KERN_DEBUG ".... register #00: %08X\n", reg_00.raw);
1280	printk(KERN_DEBUG ".......    : physical APIC id: %02X\n", reg_00.bits.ID);
1281	printk(KERN_DEBUG ".......    : Delivery Type: %X\n", reg_00.bits.delivery_type);
1282	printk(KERN_DEBUG ".......    : LTS          : %X\n", reg_00.bits.LTS);
1283
1284	printk(KERN_DEBUG ".... register #01: %08X\n", *(int *)&reg_01);
1285	printk(KERN_DEBUG ".......     : max redirection entries: %02X\n",
1286		reg_01.bits.entries);
1287
1288	printk(KERN_DEBUG ".......     : PRQ implemented: %X\n", reg_01.bits.PRQ);
1289	printk(KERN_DEBUG ".......     : IO APIC version: %02X\n",
1290		reg_01.bits.version);
1291
1292	/*
1293	 * Some Intel chipsets with IO APIC VERSION of 0x1? don't have reg_02,
1294	 * but the value of reg_02 is read as the previous read register
1295	 * value, so ignore it if reg_02 == reg_01.
1296	 */
1297	if (reg_01.bits.version >= 0x10 && reg_02.raw != reg_01.raw) {
1298		printk(KERN_DEBUG ".... register #02: %08X\n", reg_02.raw);
1299		printk(KERN_DEBUG ".......     : arbitration: %02X\n", reg_02.bits.arbitration);
1300	}
1301
1302	/*
1303	 * Some Intel chipsets with IO APIC VERSION of 0x2? don't have reg_02
1304	 * or reg_03, but the value of reg_0[23] is read as the previous read
1305	 * register value, so ignore it if reg_03 == reg_0[12].
1306	 */
1307	if (reg_01.bits.version >= 0x20 && reg_03.raw != reg_02.raw &&
1308	    reg_03.raw != reg_01.raw) {
1309		printk(KERN_DEBUG ".... register #03: %08X\n", reg_03.raw);
1310		printk(KERN_DEBUG ".......     : Boot DT    : %X\n", reg_03.bits.boot_DT);
1311	}
1312
1313	printk(KERN_DEBUG ".... IRQ redirection table:\n");
1314	io_apic_print_entries(ioapic_idx, reg_01.bits.entries);
1315}
1316
1317void __init print_IO_APICs(void)
1318{
1319	int ioapic_idx;
1320	unsigned int irq;
1321
1322	printk(KERN_DEBUG "number of MP IRQ sources: %d.\n", mp_irq_entries);
1323	for_each_ioapic(ioapic_idx)
1324		printk(KERN_DEBUG "number of IO-APIC #%d registers: %d.\n",
1325		       mpc_ioapic_id(ioapic_idx),
1326		       ioapics[ioapic_idx].nr_registers);
1327
1328	/*
1329	 * We are a bit conservative about what we expect.  We have to
1330	 * know about every hardware change ASAP.
1331	 */
1332	printk(KERN_INFO "testing the IO APIC.......................\n");
1333
1334	for_each_ioapic(ioapic_idx)
1335		print_IO_APIC(ioapic_idx);
1336
1337	printk(KERN_DEBUG "IRQ to pin mappings:\n");
1338	for_each_active_irq(irq) {
1339		struct irq_pin_list *entry;
1340		struct irq_chip *chip;
1341		struct mp_chip_data *data;
1342
1343		chip = irq_get_chip(irq);
1344		if (chip != &ioapic_chip && chip != &ioapic_ir_chip)
1345			continue;
1346		data = irq_get_chip_data(irq);
1347		if (!data)
1348			continue;
1349		if (list_empty(&data->irq_2_pin))
1350			continue;
1351
1352		printk(KERN_DEBUG "IRQ%d ", irq);
1353		for_each_irq_pin(entry, data->irq_2_pin)
1354			pr_cont("-> %d:%d", entry->apic, entry->pin);
1355		pr_cont("\n");
1356	}
1357
1358	printk(KERN_INFO ".................................... done.\n");
1359}
1360
1361/* Where if anywhere is the i8259 connect in external int mode */
1362static struct { int pin, apic; } ioapic_i8259 = { -1, -1 };
1363
1364void __init enable_IO_APIC(void)
1365{
1366	int i8259_apic, i8259_pin;
1367	int apic, pin;
1368
1369	if (ioapic_is_disabled)
1370		nr_ioapics = 0;
1371
1372	if (!nr_legacy_irqs() || !nr_ioapics)
1373		return;
1374
1375	for_each_ioapic_pin(apic, pin) {
1376		/* See if any of the pins is in ExtINT mode */
1377		struct IO_APIC_route_entry entry = ioapic_read_entry(apic, pin);
1378
1379		/* If the interrupt line is enabled and in ExtInt mode
1380		 * I have found the pin where the i8259 is connected.
1381		 */
1382		if (!entry.masked &&
1383		    entry.delivery_mode == APIC_DELIVERY_MODE_EXTINT) {
1384			ioapic_i8259.apic = apic;
1385			ioapic_i8259.pin  = pin;
1386			goto found_i8259;
1387		}
1388	}
1389 found_i8259:
1390	/* Look to see what if the MP table has reported the ExtINT */
1391	/* If we could not find the appropriate pin by looking at the ioapic
1392	 * the i8259 probably is not connected the ioapic but give the
1393	 * mptable a chance anyway.
1394	 */
1395	i8259_pin  = find_isa_irq_pin(0, mp_ExtINT);
1396	i8259_apic = find_isa_irq_apic(0, mp_ExtINT);
1397	/* Trust the MP table if nothing is setup in the hardware */
1398	if ((ioapic_i8259.pin == -1) && (i8259_pin >= 0)) {
1399		printk(KERN_WARNING "ExtINT not setup in hardware but reported by MP table\n");
1400		ioapic_i8259.pin  = i8259_pin;
1401		ioapic_i8259.apic = i8259_apic;
1402	}
1403	/* Complain if the MP table and the hardware disagree */
1404	if (((ioapic_i8259.apic != i8259_apic) || (ioapic_i8259.pin != i8259_pin)) &&
1405		(i8259_pin >= 0) && (ioapic_i8259.pin >= 0))
1406	{
1407		printk(KERN_WARNING "ExtINT in hardware and MP table differ\n");
1408	}
1409
1410	/*
1411	 * Do not trust the IO-APIC being empty at bootup
1412	 */
1413	clear_IO_APIC();
1414}
1415
1416void native_restore_boot_irq_mode(void)
1417{
1418	/*
1419	 * If the i8259 is routed through an IOAPIC
1420	 * Put that IOAPIC in virtual wire mode
1421	 * so legacy interrupts can be delivered.
1422	 */
1423	if (ioapic_i8259.pin != -1) {
1424		struct IO_APIC_route_entry entry;
1425		u32 apic_id = read_apic_id();
1426
1427		memset(&entry, 0, sizeof(entry));
1428		entry.masked		= false;
1429		entry.is_level		= false;
1430		entry.active_low	= false;
1431		entry.dest_mode_logical	= false;
1432		entry.delivery_mode	= APIC_DELIVERY_MODE_EXTINT;
1433		entry.destid_0_7	= apic_id & 0xFF;
1434		entry.virt_destid_8_14	= apic_id >> 8;
1435
1436		/*
1437		 * Add it to the IO-APIC irq-routing table:
1438		 */
1439		ioapic_write_entry(ioapic_i8259.apic, ioapic_i8259.pin, entry);
1440	}
1441
1442	if (boot_cpu_has(X86_FEATURE_APIC) || apic_from_smp_config())
1443		disconnect_bsp_APIC(ioapic_i8259.pin != -1);
1444}
1445
1446void restore_boot_irq_mode(void)
1447{
1448	if (!nr_legacy_irqs())
1449		return;
1450
1451	x86_apic_ops.restore();
1452}
1453
1454#ifdef CONFIG_X86_32
1455/*
1456 * function to set the IO-APIC physical IDs based on the
1457 * values stored in the MPC table.
1458 *
1459 * by Matt Domsch <Matt_Domsch@dell.com>  Tue Dec 21 12:25:05 CST 1999
1460 */
1461void __init setup_ioapic_ids_from_mpc_nocheck(void)
1462{
1463	union IO_APIC_reg_00 reg_00;
1464	physid_mask_t phys_id_present_map;
1465	int ioapic_idx;
1466	int i;
1467	unsigned char old_id;
1468	unsigned long flags;
1469
1470	/*
1471	 * This is broken; anything with a real cpu count has to
1472	 * circumvent this idiocy regardless.
1473	 */
1474	apic->ioapic_phys_id_map(&phys_cpu_present_map, &phys_id_present_map);
1475
1476	/*
1477	 * Set the IOAPIC ID to the value stored in the MPC table.
1478	 */
1479	for_each_ioapic(ioapic_idx) {
1480		/* Read the register 0 value */
1481		raw_spin_lock_irqsave(&ioapic_lock, flags);
1482		reg_00.raw = io_apic_read(ioapic_idx, 0);
1483		raw_spin_unlock_irqrestore(&ioapic_lock, flags);
1484
1485		old_id = mpc_ioapic_id(ioapic_idx);
1486
1487		if (mpc_ioapic_id(ioapic_idx) >= get_physical_broadcast()) {
1488			printk(KERN_ERR "BIOS bug, IO-APIC#%d ID is %d in the MPC table!...\n",
1489				ioapic_idx, mpc_ioapic_id(ioapic_idx));
1490			printk(KERN_ERR "... fixing up to %d. (tell your hw vendor)\n",
1491				reg_00.bits.ID);
1492			ioapics[ioapic_idx].mp_config.apicid = reg_00.bits.ID;
1493		}
1494
1495		/*
1496		 * Sanity check, is the ID really free? Every APIC in a
1497		 * system must have a unique ID or we get lots of nice
1498		 * 'stuck on smp_invalidate_needed IPI wait' messages.
1499		 */
1500		if (apic->check_apicid_used(&phys_id_present_map,
1501					    mpc_ioapic_id(ioapic_idx))) {
1502			printk(KERN_ERR "BIOS bug, IO-APIC#%d ID %d is already used!...\n",
1503				ioapic_idx, mpc_ioapic_id(ioapic_idx));
1504			for (i = 0; i < get_physical_broadcast(); i++)
1505				if (!physid_isset(i, phys_id_present_map))
1506					break;
1507			if (i >= get_physical_broadcast())
1508				panic("Max APIC ID exceeded!\n");
1509			printk(KERN_ERR "... fixing up to %d. (tell your hw vendor)\n",
1510				i);
1511			physid_set(i, phys_id_present_map);
1512			ioapics[ioapic_idx].mp_config.apicid = i;
1513		} else {
1514			apic_printk(APIC_VERBOSE, "Setting %d in the phys_id_present_map\n",
1515				    mpc_ioapic_id(ioapic_idx));
1516			physid_set(mpc_ioapic_id(ioapic_idx), phys_id_present_map);
 
 
 
 
1517		}
1518
1519		/*
1520		 * We need to adjust the IRQ routing table
1521		 * if the ID changed.
1522		 */
1523		if (old_id != mpc_ioapic_id(ioapic_idx))
1524			for (i = 0; i < mp_irq_entries; i++)
1525				if (mp_irqs[i].dstapic == old_id)
1526					mp_irqs[i].dstapic
1527						= mpc_ioapic_id(ioapic_idx);
1528
1529		/*
1530		 * Update the ID register according to the right value
1531		 * from the MPC table if they are different.
1532		 */
1533		if (mpc_ioapic_id(ioapic_idx) == reg_00.bits.ID)
1534			continue;
1535
1536		apic_printk(APIC_VERBOSE, KERN_INFO
1537			"...changing IO-APIC physical APIC ID to %d ...",
1538			mpc_ioapic_id(ioapic_idx));
1539
1540		reg_00.bits.ID = mpc_ioapic_id(ioapic_idx);
1541		raw_spin_lock_irqsave(&ioapic_lock, flags);
1542		io_apic_write(ioapic_idx, 0, reg_00.raw);
1543		raw_spin_unlock_irqrestore(&ioapic_lock, flags);
1544
1545		/*
1546		 * Sanity check
1547		 */
1548		raw_spin_lock_irqsave(&ioapic_lock, flags);
1549		reg_00.raw = io_apic_read(ioapic_idx, 0);
1550		raw_spin_unlock_irqrestore(&ioapic_lock, flags);
1551		if (reg_00.bits.ID != mpc_ioapic_id(ioapic_idx))
1552			pr_cont("could not set ID!\n");
1553		else
1554			apic_printk(APIC_VERBOSE, " ok.\n");
1555	}
1556}
1557
1558void __init setup_ioapic_ids_from_mpc(void)
1559{
1560
1561	if (acpi_ioapic)
1562		return;
1563	/*
1564	 * Don't check I/O APIC IDs for xAPIC systems.  They have
1565	 * no meaning without the serial APIC bus.
1566	 */
1567	if (!(boot_cpu_data.x86_vendor == X86_VENDOR_INTEL)
1568		|| APIC_XAPIC(boot_cpu_apic_version))
1569		return;
1570	setup_ioapic_ids_from_mpc_nocheck();
1571}
1572#endif
1573
1574int no_timer_check __initdata;
1575
1576static int __init notimercheck(char *s)
1577{
1578	no_timer_check = 1;
1579	return 1;
1580}
1581__setup("no_timer_check", notimercheck);
1582
1583static void __init delay_with_tsc(void)
1584{
1585	unsigned long long start, now;
1586	unsigned long end = jiffies + 4;
1587
1588	start = rdtsc();
1589
1590	/*
1591	 * We don't know the TSC frequency yet, but waiting for
1592	 * 40000000000/HZ TSC cycles is safe:
1593	 * 4 GHz == 10 jiffies
1594	 * 1 GHz == 40 jiffies
1595	 */
1596	do {
1597		rep_nop();
1598		now = rdtsc();
1599	} while ((now - start) < 40000000000ULL / HZ &&
1600		time_before_eq(jiffies, end));
1601}
1602
1603static void __init delay_without_tsc(void)
1604{
1605	unsigned long end = jiffies + 4;
1606	int band = 1;
1607
1608	/*
1609	 * We don't know any frequency yet, but waiting for
1610	 * 40940000000/HZ cycles is safe:
1611	 * 4 GHz == 10 jiffies
1612	 * 1 GHz == 40 jiffies
1613	 * 1 << 1 + 1 << 2 +...+ 1 << 11 = 4094
1614	 */
1615	do {
1616		__delay(((1U << band++) * 10000000UL) / HZ);
1617	} while (band < 12 && time_before_eq(jiffies, end));
1618}
1619
1620/*
1621 * There is a nasty bug in some older SMP boards, their mptable lies
1622 * about the timer IRQ. We do the following to work around the situation:
1623 *
1624 *	- timer IRQ defaults to IO-APIC IRQ
1625 *	- if this function detects that timer IRQs are defunct, then we fall
1626 *	  back to ISA timer IRQs
1627 */
1628static int __init timer_irq_works(void)
1629{
1630	unsigned long t1 = jiffies;
1631
1632	if (no_timer_check)
1633		return 1;
1634
1635	local_irq_enable();
1636	if (boot_cpu_has(X86_FEATURE_TSC))
1637		delay_with_tsc();
1638	else
1639		delay_without_tsc();
1640
1641	/*
1642	 * Expect a few ticks at least, to be sure some possible
1643	 * glue logic does not lock up after one or two first
1644	 * ticks in a non-ExtINT mode.  Also the local APIC
1645	 * might have cached one ExtINT interrupt.  Finally, at
1646	 * least one tick may be lost due to delays.
1647	 */
1648
1649	local_irq_disable();
1650
1651	/* Did jiffies advance? */
1652	return time_after(jiffies, t1 + 4);
1653}
1654
1655/*
1656 * In the SMP+IOAPIC case it might happen that there are an unspecified
1657 * number of pending IRQ events unhandled. These cases are very rare,
1658 * so we 'resend' these IRQs via IPIs, to the same CPU. It's much
1659 * better to do it this way as thus we do not have to be aware of
1660 * 'pending' interrupts in the IRQ path, except at this point.
1661 */
1662/*
1663 * Edge triggered needs to resend any interrupt
1664 * that was delayed but this is now handled in the device
1665 * independent code.
1666 */
1667
1668/*
1669 * Starting up a edge-triggered IO-APIC interrupt is
1670 * nasty - we need to make sure that we get the edge.
1671 * If it is already asserted for some reason, we need
1672 * return 1 to indicate that is was pending.
1673 *
1674 * This is not complete - we should be able to fake
1675 * an edge even if it isn't on the 8259A...
1676 */
1677static unsigned int startup_ioapic_irq(struct irq_data *data)
1678{
1679	int was_pending = 0, irq = data->irq;
1680	unsigned long flags;
1681
1682	raw_spin_lock_irqsave(&ioapic_lock, flags);
1683	if (irq < nr_legacy_irqs()) {
1684		legacy_pic->mask(irq);
1685		if (legacy_pic->irq_pending(irq))
1686			was_pending = 1;
1687	}
1688	__unmask_ioapic(data->chip_data);
1689	raw_spin_unlock_irqrestore(&ioapic_lock, flags);
1690
1691	return was_pending;
1692}
1693
1694atomic_t irq_mis_count;
1695
1696#ifdef CONFIG_GENERIC_PENDING_IRQ
1697static bool io_apic_level_ack_pending(struct mp_chip_data *data)
1698{
1699	struct irq_pin_list *entry;
1700	unsigned long flags;
1701
1702	raw_spin_lock_irqsave(&ioapic_lock, flags);
1703	for_each_irq_pin(entry, data->irq_2_pin) {
1704		struct IO_APIC_route_entry e;
1705		int pin;
1706
1707		pin = entry->pin;
1708		e.w1 = io_apic_read(entry->apic, 0x10 + pin*2);
1709		/* Is the remote IRR bit set? */
1710		if (e.irr) {
1711			raw_spin_unlock_irqrestore(&ioapic_lock, flags);
1712			return true;
1713		}
1714	}
1715	raw_spin_unlock_irqrestore(&ioapic_lock, flags);
1716
1717	return false;
1718}
1719
1720static inline bool ioapic_prepare_move(struct irq_data *data)
1721{
1722	/* If we are moving the IRQ we need to mask it */
1723	if (unlikely(irqd_is_setaffinity_pending(data))) {
1724		if (!irqd_irq_masked(data))
1725			mask_ioapic_irq(data);
1726		return true;
1727	}
1728	return false;
1729}
1730
1731static inline void ioapic_finish_move(struct irq_data *data, bool moveit)
1732{
1733	if (unlikely(moveit)) {
1734		/* Only migrate the irq if the ack has been received.
1735		 *
1736		 * On rare occasions the broadcast level triggered ack gets
1737		 * delayed going to ioapics, and if we reprogram the
1738		 * vector while Remote IRR is still set the irq will never
1739		 * fire again.
1740		 *
1741		 * To prevent this scenario we read the Remote IRR bit
1742		 * of the ioapic.  This has two effects.
1743		 * - On any sane system the read of the ioapic will
1744		 *   flush writes (and acks) going to the ioapic from
1745		 *   this cpu.
1746		 * - We get to see if the ACK has actually been delivered.
1747		 *
1748		 * Based on failed experiments of reprogramming the
1749		 * ioapic entry from outside of irq context starting
1750		 * with masking the ioapic entry and then polling until
1751		 * Remote IRR was clear before reprogramming the
1752		 * ioapic I don't trust the Remote IRR bit to be
1753		 * completely accurate.
1754		 *
1755		 * However there appears to be no other way to plug
1756		 * this race, so if the Remote IRR bit is not
1757		 * accurate and is causing problems then it is a hardware bug
1758		 * and you can go talk to the chipset vendor about it.
1759		 */
1760		if (!io_apic_level_ack_pending(data->chip_data))
1761			irq_move_masked_irq(data);
1762		/* If the IRQ is masked in the core, leave it: */
1763		if (!irqd_irq_masked(data))
1764			unmask_ioapic_irq(data);
1765	}
1766}
1767#else
1768static inline bool ioapic_prepare_move(struct irq_data *data)
1769{
1770	return false;
1771}
1772static inline void ioapic_finish_move(struct irq_data *data, bool moveit)
1773{
1774}
1775#endif
1776
1777static void ioapic_ack_level(struct irq_data *irq_data)
1778{
1779	struct irq_cfg *cfg = irqd_cfg(irq_data);
1780	unsigned long v;
1781	bool moveit;
1782	int i;
1783
1784	irq_complete_move(cfg);
1785	moveit = ioapic_prepare_move(irq_data);
1786
1787	/*
1788	 * It appears there is an erratum which affects at least version 0x11
1789	 * of I/O APIC (that's the 82093AA and cores integrated into various
1790	 * chipsets).  Under certain conditions a level-triggered interrupt is
1791	 * erroneously delivered as edge-triggered one but the respective IRR
1792	 * bit gets set nevertheless.  As a result the I/O unit expects an EOI
1793	 * message but it will never arrive and further interrupts are blocked
1794	 * from the source.  The exact reason is so far unknown, but the
1795	 * phenomenon was observed when two consecutive interrupt requests
1796	 * from a given source get delivered to the same CPU and the source is
1797	 * temporarily disabled in between.
1798	 *
1799	 * A workaround is to simulate an EOI message manually.  We achieve it
1800	 * by setting the trigger mode to edge and then to level when the edge
1801	 * trigger mode gets detected in the TMR of a local APIC for a
1802	 * level-triggered interrupt.  We mask the source for the time of the
1803	 * operation to prevent an edge-triggered interrupt escaping meanwhile.
1804	 * The idea is from Manfred Spraul.  --macro
1805	 *
1806	 * Also in the case when cpu goes offline, fixup_irqs() will forward
1807	 * any unhandled interrupt on the offlined cpu to the new cpu
1808	 * destination that is handling the corresponding interrupt. This
1809	 * interrupt forwarding is done via IPI's. Hence, in this case also
1810	 * level-triggered io-apic interrupt will be seen as an edge
1811	 * interrupt in the IRR. And we can't rely on the cpu's EOI
1812	 * to be broadcasted to the IO-APIC's which will clear the remoteIRR
1813	 * corresponding to the level-triggered interrupt. Hence on IO-APIC's
1814	 * supporting EOI register, we do an explicit EOI to clear the
1815	 * remote IRR and on IO-APIC's which don't have an EOI register,
1816	 * we use the above logic (mask+edge followed by unmask+level) from
1817	 * Manfred Spraul to clear the remote IRR.
1818	 */
1819	i = cfg->vector;
1820	v = apic_read(APIC_TMR + ((i & ~0x1f) >> 1));
1821
1822	/*
1823	 * We must acknowledge the irq before we move it or the acknowledge will
1824	 * not propagate properly.
1825	 */
1826	apic_eoi();
1827
1828	/*
1829	 * Tail end of clearing remote IRR bit (either by delivering the EOI
1830	 * message via io-apic EOI register write or simulating it using
1831	 * mask+edge followed by unmask+level logic) manually when the
1832	 * level triggered interrupt is seen as the edge triggered interrupt
1833	 * at the cpu.
1834	 */
1835	if (!(v & (1 << (i & 0x1f)))) {
1836		atomic_inc(&irq_mis_count);
1837		eoi_ioapic_pin(cfg->vector, irq_data->chip_data);
1838	}
1839
1840	ioapic_finish_move(irq_data, moveit);
1841}
1842
1843static void ioapic_ir_ack_level(struct irq_data *irq_data)
1844{
1845	struct mp_chip_data *data = irq_data->chip_data;
1846
1847	/*
1848	 * Intr-remapping uses pin number as the virtual vector
1849	 * in the RTE. Actual vector is programmed in
1850	 * intr-remapping table entry. Hence for the io-apic
1851	 * EOI we use the pin number.
1852	 */
1853	apic_ack_irq(irq_data);
1854	eoi_ioapic_pin(data->entry.vector, data);
1855}
1856
1857/*
1858 * The I/OAPIC is just a device for generating MSI messages from legacy
1859 * interrupt pins. Various fields of the RTE translate into bits of the
1860 * resulting MSI which had a historical meaning.
1861 *
1862 * With interrupt remapping, many of those bits have different meanings
1863 * in the underlying MSI, but the way that the I/OAPIC transforms them
1864 * from its RTE to the MSI message is the same. This function allows
1865 * the parent IRQ domain to compose the MSI message, then takes the
1866 * relevant bits to put them in the appropriate places in the RTE in
1867 * order to generate that message when the IRQ happens.
1868 *
1869 * The setup here relies on a preconfigured route entry (is_level,
1870 * active_low, masked) because the parent domain is merely composing the
1871 * generic message routing information which is used for the MSI.
1872 */
1873static void ioapic_setup_msg_from_msi(struct irq_data *irq_data,
1874				      struct IO_APIC_route_entry *entry)
1875{
1876	struct msi_msg msg;
1877
1878	/* Let the parent domain compose the MSI message */
1879	irq_chip_compose_msi_msg(irq_data, &msg);
1880
1881	/*
1882	 * - Real vector
1883	 * - DMAR/IR: 8bit subhandle (ioapic.pin)
1884	 * - AMD/IR:  8bit IRTE index
1885	 */
1886	entry->vector			= msg.arch_data.vector;
1887	/* Delivery mode (for DMAR/IR all 0) */
1888	entry->delivery_mode		= msg.arch_data.delivery_mode;
1889	/* Destination mode or DMAR/IR index bit 15 */
1890	entry->dest_mode_logical	= msg.arch_addr_lo.dest_mode_logical;
1891	/* DMAR/IR: 1, 0 for all other modes */
1892	entry->ir_format		= msg.arch_addr_lo.dmar_format;
1893	/*
1894	 * - DMAR/IR: index bit 0-14.
1895	 *
1896	 * - Virt: If the host supports x2apic without a virtualized IR
1897	 *	   unit then bit 0-6 of dmar_index_0_14 are providing bit
1898	 *	   8-14 of the destination id.
1899	 *
1900	 * All other modes have bit 0-6 of dmar_index_0_14 cleared and the
1901	 * topmost 8 bits are destination id bit 0-7 (entry::destid_0_7).
1902	 */
1903	entry->ir_index_0_14		= msg.arch_addr_lo.dmar_index_0_14;
1904}
1905
1906static void ioapic_configure_entry(struct irq_data *irqd)
1907{
1908	struct mp_chip_data *mpd = irqd->chip_data;
1909	struct irq_pin_list *entry;
1910
1911	ioapic_setup_msg_from_msi(irqd, &mpd->entry);
1912
1913	for_each_irq_pin(entry, mpd->irq_2_pin)
1914		__ioapic_write_entry(entry->apic, entry->pin, mpd->entry);
1915}
1916
1917static int ioapic_set_affinity(struct irq_data *irq_data,
1918			       const struct cpumask *mask, bool force)
1919{
1920	struct irq_data *parent = irq_data->parent_data;
1921	unsigned long flags;
1922	int ret;
1923
1924	ret = parent->chip->irq_set_affinity(parent, mask, force);
1925	raw_spin_lock_irqsave(&ioapic_lock, flags);
1926	if (ret >= 0 && ret != IRQ_SET_MASK_OK_DONE)
1927		ioapic_configure_entry(irq_data);
1928	raw_spin_unlock_irqrestore(&ioapic_lock, flags);
1929
1930	return ret;
1931}
1932
1933/*
1934 * Interrupt shutdown masks the ioapic pin, but the interrupt might already
1935 * be in flight, but not yet serviced by the target CPU. That means
1936 * __synchronize_hardirq() would return and claim that everything is calmed
1937 * down. So free_irq() would proceed and deactivate the interrupt and free
1938 * resources.
1939 *
1940 * Once the target CPU comes around to service it it will find a cleared
1941 * vector and complain. While the spurious interrupt is harmless, the full
1942 * release of resources might prevent the interrupt from being acknowledged
1943 * which keeps the hardware in a weird state.
1944 *
1945 * Verify that the corresponding Remote-IRR bits are clear.
1946 */
1947static int ioapic_irq_get_chip_state(struct irq_data *irqd,
1948				   enum irqchip_irq_state which,
1949				   bool *state)
1950{
1951	struct mp_chip_data *mcd = irqd->chip_data;
1952	struct IO_APIC_route_entry rentry;
1953	struct irq_pin_list *p;
1954
1955	if (which != IRQCHIP_STATE_ACTIVE)
1956		return -EINVAL;
1957
1958	*state = false;
1959	raw_spin_lock(&ioapic_lock);
1960	for_each_irq_pin(p, mcd->irq_2_pin) {
1961		rentry = __ioapic_read_entry(p->apic, p->pin);
1962		/*
1963		 * The remote IRR is only valid in level trigger mode. It's
1964		 * meaning is undefined for edge triggered interrupts and
1965		 * irrelevant because the IO-APIC treats them as fire and
1966		 * forget.
1967		 */
1968		if (rentry.irr && rentry.is_level) {
1969			*state = true;
1970			break;
1971		}
1972	}
1973	raw_spin_unlock(&ioapic_lock);
1974	return 0;
1975}
1976
1977static struct irq_chip ioapic_chip __read_mostly = {
1978	.name			= "IO-APIC",
1979	.irq_startup		= startup_ioapic_irq,
1980	.irq_mask		= mask_ioapic_irq,
1981	.irq_unmask		= unmask_ioapic_irq,
1982	.irq_ack		= irq_chip_ack_parent,
1983	.irq_eoi		= ioapic_ack_level,
1984	.irq_set_affinity	= ioapic_set_affinity,
1985	.irq_retrigger		= irq_chip_retrigger_hierarchy,
1986	.irq_get_irqchip_state	= ioapic_irq_get_chip_state,
1987	.flags			= IRQCHIP_SKIP_SET_WAKE |
1988				  IRQCHIP_AFFINITY_PRE_STARTUP,
1989};
1990
1991static struct irq_chip ioapic_ir_chip __read_mostly = {
1992	.name			= "IR-IO-APIC",
1993	.irq_startup		= startup_ioapic_irq,
1994	.irq_mask		= mask_ioapic_irq,
1995	.irq_unmask		= unmask_ioapic_irq,
1996	.irq_ack		= irq_chip_ack_parent,
1997	.irq_eoi		= ioapic_ir_ack_level,
1998	.irq_set_affinity	= ioapic_set_affinity,
1999	.irq_retrigger		= irq_chip_retrigger_hierarchy,
2000	.irq_get_irqchip_state	= ioapic_irq_get_chip_state,
2001	.flags			= IRQCHIP_SKIP_SET_WAKE |
2002				  IRQCHIP_AFFINITY_PRE_STARTUP,
2003};
2004
2005static inline void init_IO_APIC_traps(void)
2006{
2007	struct irq_cfg *cfg;
2008	unsigned int irq;
2009
2010	for_each_active_irq(irq) {
2011		cfg = irq_cfg(irq);
2012		if (IO_APIC_IRQ(irq) && cfg && !cfg->vector) {
2013			/*
2014			 * Hmm.. We don't have an entry for this,
2015			 * so default to an old-fashioned 8259
2016			 * interrupt if we can..
2017			 */
2018			if (irq < nr_legacy_irqs())
2019				legacy_pic->make_irq(irq);
2020			else
2021				/* Strange. Oh, well.. */
2022				irq_set_chip(irq, &no_irq_chip);
2023		}
2024	}
2025}
2026
2027/*
2028 * The local APIC irq-chip implementation:
2029 */
2030
2031static void mask_lapic_irq(struct irq_data *data)
2032{
2033	unsigned long v;
2034
2035	v = apic_read(APIC_LVT0);
2036	apic_write(APIC_LVT0, v | APIC_LVT_MASKED);
2037}
2038
2039static void unmask_lapic_irq(struct irq_data *data)
2040{
2041	unsigned long v;
2042
2043	v = apic_read(APIC_LVT0);
2044	apic_write(APIC_LVT0, v & ~APIC_LVT_MASKED);
2045}
2046
2047static void ack_lapic_irq(struct irq_data *data)
2048{
2049	apic_eoi();
2050}
2051
2052static struct irq_chip lapic_chip __read_mostly = {
2053	.name		= "local-APIC",
2054	.irq_mask	= mask_lapic_irq,
2055	.irq_unmask	= unmask_lapic_irq,
2056	.irq_ack	= ack_lapic_irq,
2057};
2058
2059static void lapic_register_intr(int irq)
2060{
2061	irq_clear_status_flags(irq, IRQ_LEVEL);
2062	irq_set_chip_and_handler_name(irq, &lapic_chip, handle_edge_irq,
2063				      "edge");
2064}
2065
2066/*
2067 * This looks a bit hackish but it's about the only one way of sending
2068 * a few INTA cycles to 8259As and any associated glue logic.  ICR does
2069 * not support the ExtINT mode, unfortunately.  We need to send these
2070 * cycles as some i82489DX-based boards have glue logic that keeps the
2071 * 8259A interrupt line asserted until INTA.  --macro
2072 */
2073static inline void __init unlock_ExtINT_logic(void)
2074{
2075	int apic, pin, i;
2076	struct IO_APIC_route_entry entry0, entry1;
2077	unsigned char save_control, save_freq_select;
2078	u32 apic_id;
2079
2080	pin  = find_isa_irq_pin(8, mp_INT);
2081	if (pin == -1) {
2082		WARN_ON_ONCE(1);
2083		return;
2084	}
2085	apic = find_isa_irq_apic(8, mp_INT);
2086	if (apic == -1) {
2087		WARN_ON_ONCE(1);
2088		return;
2089	}
2090
2091	entry0 = ioapic_read_entry(apic, pin);
2092	clear_IO_APIC_pin(apic, pin);
2093
2094	apic_id = read_apic_id();
2095	memset(&entry1, 0, sizeof(entry1));
2096
2097	entry1.dest_mode_logical	= true;
2098	entry1.masked			= false;
2099	entry1.destid_0_7		= apic_id & 0xFF;
2100	entry1.virt_destid_8_14		= apic_id >> 8;
2101	entry1.delivery_mode		= APIC_DELIVERY_MODE_EXTINT;
2102	entry1.active_low		= entry0.active_low;
2103	entry1.is_level			= false;
2104	entry1.vector = 0;
2105
2106	ioapic_write_entry(apic, pin, entry1);
2107
2108	save_control = CMOS_READ(RTC_CONTROL);
2109	save_freq_select = CMOS_READ(RTC_FREQ_SELECT);
2110	CMOS_WRITE((save_freq_select & ~RTC_RATE_SELECT) | 0x6,
2111		   RTC_FREQ_SELECT);
2112	CMOS_WRITE(save_control | RTC_PIE, RTC_CONTROL);
2113
2114	i = 100;
2115	while (i-- > 0) {
2116		mdelay(10);
2117		if ((CMOS_READ(RTC_INTR_FLAGS) & RTC_PF) == RTC_PF)
2118			i -= 10;
2119	}
2120
2121	CMOS_WRITE(save_control, RTC_CONTROL);
2122	CMOS_WRITE(save_freq_select, RTC_FREQ_SELECT);
2123	clear_IO_APIC_pin(apic, pin);
2124
2125	ioapic_write_entry(apic, pin, entry0);
2126}
2127
2128static int disable_timer_pin_1 __initdata;
2129/* Actually the next is obsolete, but keep it for paranoid reasons -AK */
2130static int __init disable_timer_pin_setup(char *arg)
2131{
2132	disable_timer_pin_1 = 1;
2133	return 0;
2134}
2135early_param("disable_timer_pin_1", disable_timer_pin_setup);
2136
2137static int mp_alloc_timer_irq(int ioapic, int pin)
2138{
2139	int irq = -1;
2140	struct irq_domain *domain = mp_ioapic_irqdomain(ioapic);
2141
2142	if (domain) {
2143		struct irq_alloc_info info;
2144
2145		ioapic_set_alloc_attr(&info, NUMA_NO_NODE, 0, 0);
2146		info.devid = mpc_ioapic_id(ioapic);
2147		info.ioapic.pin = pin;
2148		mutex_lock(&ioapic_mutex);
2149		irq = alloc_isa_irq_from_domain(domain, 0, ioapic, pin, &info);
2150		mutex_unlock(&ioapic_mutex);
2151	}
2152
2153	return irq;
2154}
2155
2156/*
2157 * This code may look a bit paranoid, but it's supposed to cooperate with
2158 * a wide range of boards and BIOS bugs.  Fortunately only the timer IRQ
2159 * is so screwy.  Thanks to Brian Perkins for testing/hacking this beast
2160 * fanatically on his truly buggy board.
2161 *
2162 * FIXME: really need to revamp this for all platforms.
2163 */
2164static inline void __init check_timer(void)
2165{
2166	struct irq_data *irq_data = irq_get_irq_data(0);
2167	struct mp_chip_data *data = irq_data->chip_data;
2168	struct irq_cfg *cfg = irqd_cfg(irq_data);
2169	int node = cpu_to_node(0);
2170	int apic1, pin1, apic2, pin2;
2171	int no_pin1 = 0;
2172
2173	if (!global_clock_event)
2174		return;
2175
2176	local_irq_disable();
2177
2178	/*
2179	 * get/set the timer IRQ vector:
2180	 */
2181	legacy_pic->mask(0);
2182
2183	/*
2184	 * As IRQ0 is to be enabled in the 8259A, the virtual
2185	 * wire has to be disabled in the local APIC.  Also
2186	 * timer interrupts need to be acknowledged manually in
2187	 * the 8259A for the i82489DX when using the NMI
2188	 * watchdog as that APIC treats NMIs as level-triggered.
2189	 * The AEOI mode will finish them in the 8259A
2190	 * automatically.
2191	 */
2192	apic_write(APIC_LVT0, APIC_LVT_MASKED | APIC_DM_EXTINT);
2193	legacy_pic->init(1);
2194
2195	pin1  = find_isa_irq_pin(0, mp_INT);
2196	apic1 = find_isa_irq_apic(0, mp_INT);
2197	pin2  = ioapic_i8259.pin;
2198	apic2 = ioapic_i8259.apic;
2199
2200	apic_printk(APIC_QUIET, KERN_INFO "..TIMER: vector=0x%02X "
2201		    "apic1=%d pin1=%d apic2=%d pin2=%d\n",
2202		    cfg->vector, apic1, pin1, apic2, pin2);
2203
2204	/*
2205	 * Some BIOS writers are clueless and report the ExtINTA
2206	 * I/O APIC input from the cascaded 8259A as the timer
2207	 * interrupt input.  So just in case, if only one pin
2208	 * was found above, try it both directly and through the
2209	 * 8259A.
2210	 */
2211	if (pin1 == -1) {
2212		panic_if_irq_remap("BIOS bug: timer not connected to IO-APIC");
2213		pin1 = pin2;
2214		apic1 = apic2;
2215		no_pin1 = 1;
2216	} else if (pin2 == -1) {
2217		pin2 = pin1;
2218		apic2 = apic1;
2219	}
2220
2221	if (pin1 != -1) {
2222		/* Ok, does IRQ0 through the IOAPIC work? */
2223		if (no_pin1) {
2224			mp_alloc_timer_irq(apic1, pin1);
2225		} else {
2226			/*
2227			 * for edge trigger, it's already unmasked,
2228			 * so only need to unmask if it is level-trigger
2229			 * do we really have level trigger timer?
2230			 */
2231			int idx = find_irq_entry(apic1, pin1, mp_INT);
2232
2233			if (idx != -1 && irq_is_level(idx))
2234				unmask_ioapic_irq(irq_get_irq_data(0));
2235		}
2236		irq_domain_deactivate_irq(irq_data);
2237		irq_domain_activate_irq(irq_data, false);
2238		if (timer_irq_works()) {
2239			if (disable_timer_pin_1 > 0)
2240				clear_IO_APIC_pin(0, pin1);
2241			goto out;
2242		}
2243		panic_if_irq_remap("timer doesn't work through Interrupt-remapped IO-APIC");
2244		clear_IO_APIC_pin(apic1, pin1);
2245		if (!no_pin1)
2246			apic_printk(APIC_QUIET, KERN_ERR "..MP-BIOS bug: "
2247				    "8254 timer not connected to IO-APIC\n");
2248
2249		apic_printk(APIC_QUIET, KERN_INFO "...trying to set up timer "
2250			    "(IRQ0) through the 8259A ...\n");
2251		apic_printk(APIC_QUIET, KERN_INFO
2252			    "..... (found apic %d pin %d) ...\n", apic2, pin2);
2253		/*
2254		 * legacy devices should be connected to IO APIC #0
2255		 */
2256		replace_pin_at_irq_node(data, node, apic1, pin1, apic2, pin2);
2257		irq_domain_deactivate_irq(irq_data);
2258		irq_domain_activate_irq(irq_data, false);
2259		legacy_pic->unmask(0);
2260		if (timer_irq_works()) {
2261			apic_printk(APIC_QUIET, KERN_INFO "....... works.\n");
2262			goto out;
2263		}
2264		/*
2265		 * Cleanup, just in case ...
2266		 */
2267		legacy_pic->mask(0);
2268		clear_IO_APIC_pin(apic2, pin2);
2269		apic_printk(APIC_QUIET, KERN_INFO "....... failed.\n");
2270	}
2271
2272	apic_printk(APIC_QUIET, KERN_INFO
2273		    "...trying to set up timer as Virtual Wire IRQ...\n");
2274
2275	lapic_register_intr(0);
2276	apic_write(APIC_LVT0, APIC_DM_FIXED | cfg->vector);	/* Fixed mode */
2277	legacy_pic->unmask(0);
2278
2279	if (timer_irq_works()) {
2280		apic_printk(APIC_QUIET, KERN_INFO "..... works.\n");
2281		goto out;
2282	}
2283	legacy_pic->mask(0);
2284	apic_write(APIC_LVT0, APIC_LVT_MASKED | APIC_DM_FIXED | cfg->vector);
2285	apic_printk(APIC_QUIET, KERN_INFO "..... failed.\n");
2286
2287	apic_printk(APIC_QUIET, KERN_INFO
2288		    "...trying to set up timer as ExtINT IRQ...\n");
2289
2290	legacy_pic->init(0);
2291	legacy_pic->make_irq(0);
2292	apic_write(APIC_LVT0, APIC_DM_EXTINT);
2293	legacy_pic->unmask(0);
2294
2295	unlock_ExtINT_logic();
2296
2297	if (timer_irq_works()) {
2298		apic_printk(APIC_QUIET, KERN_INFO "..... works.\n");
2299		goto out;
2300	}
2301	apic_printk(APIC_QUIET, KERN_INFO "..... failed :(.\n");
2302	if (apic_is_x2apic_enabled())
2303		apic_printk(APIC_QUIET, KERN_INFO
2304			    "Perhaps problem with the pre-enabled x2apic mode\n"
2305			    "Try booting with x2apic and interrupt-remapping disabled in the bios.\n");
2306	panic("IO-APIC + timer doesn't work!  Boot with apic=debug and send a "
2307		"report.  Then try booting with the 'noapic' option.\n");
2308out:
2309	local_irq_enable();
2310}
2311
2312/*
2313 * Traditionally ISA IRQ2 is the cascade IRQ, and is not available
2314 * to devices.  However there may be an I/O APIC pin available for
2315 * this interrupt regardless.  The pin may be left unconnected, but
2316 * typically it will be reused as an ExtINT cascade interrupt for
2317 * the master 8259A.  In the MPS case such a pin will normally be
2318 * reported as an ExtINT interrupt in the MP table.  With ACPI
2319 * there is no provision for ExtINT interrupts, and in the absence
2320 * of an override it would be treated as an ordinary ISA I/O APIC
2321 * interrupt, that is edge-triggered and unmasked by default.  We
2322 * used to do this, but it caused problems on some systems because
2323 * of the NMI watchdog and sometimes IRQ0 of the 8254 timer using
2324 * the same ExtINT cascade interrupt to drive the local APIC of the
2325 * bootstrap processor.  Therefore we refrain from routing IRQ2 to
2326 * the I/O APIC in all cases now.  No actual device should request
2327 * it anyway.  --macro
2328 */
2329#define PIC_IRQS	(1UL << PIC_CASCADE_IR)
2330
2331static int mp_irqdomain_create(int ioapic)
2332{
2333	struct irq_domain *parent;
2334	int hwirqs = mp_ioapic_pin_count(ioapic);
2335	struct ioapic *ip = &ioapics[ioapic];
2336	struct ioapic_domain_cfg *cfg = &ip->irqdomain_cfg;
2337	struct mp_ioapic_gsi *gsi_cfg = mp_ioapic_gsi_routing(ioapic);
2338	struct fwnode_handle *fn;
2339	struct irq_fwspec fwspec;
2340
2341	if (cfg->type == IOAPIC_DOMAIN_INVALID)
2342		return 0;
2343
2344	/* Handle device tree enumerated APICs proper */
2345	if (cfg->dev) {
2346		fn = of_node_to_fwnode(cfg->dev);
2347	} else {
2348		fn = irq_domain_alloc_named_id_fwnode("IO-APIC", mpc_ioapic_id(ioapic));
2349		if (!fn)
2350			return -ENOMEM;
2351	}
2352
2353	fwspec.fwnode = fn;
2354	fwspec.param_count = 1;
2355	fwspec.param[0] = mpc_ioapic_id(ioapic);
2356
2357	parent = irq_find_matching_fwspec(&fwspec, DOMAIN_BUS_ANY);
2358	if (!parent) {
2359		if (!cfg->dev)
2360			irq_domain_free_fwnode(fn);
2361		return -ENODEV;
2362	}
2363
2364	ip->irqdomain = irq_domain_create_hierarchy(parent, 0, hwirqs, fn, cfg->ops,
2365						    (void *)(long)ioapic);
 
2366	if (!ip->irqdomain) {
2367		/* Release fw handle if it was allocated above */
2368		if (!cfg->dev)
2369			irq_domain_free_fwnode(fn);
2370		return -ENOMEM;
2371	}
2372
 
 
2373	if (cfg->type == IOAPIC_DOMAIN_LEGACY ||
2374	    cfg->type == IOAPIC_DOMAIN_STRICT)
2375		ioapic_dynirq_base = max(ioapic_dynirq_base,
2376					 gsi_cfg->gsi_end + 1);
2377
2378	return 0;
2379}
2380
2381static void ioapic_destroy_irqdomain(int idx)
2382{
2383	struct ioapic_domain_cfg *cfg = &ioapics[idx].irqdomain_cfg;
2384	struct fwnode_handle *fn = ioapics[idx].irqdomain->fwnode;
2385
2386	if (ioapics[idx].irqdomain) {
2387		irq_domain_remove(ioapics[idx].irqdomain);
2388		if (!cfg->dev)
2389			irq_domain_free_fwnode(fn);
2390		ioapics[idx].irqdomain = NULL;
2391	}
2392}
2393
2394void __init setup_IO_APIC(void)
2395{
2396	int ioapic;
2397
2398	if (ioapic_is_disabled || !nr_ioapics)
2399		return;
2400
2401	io_apic_irqs = nr_legacy_irqs() ? ~PIC_IRQS : ~0UL;
2402
2403	apic_printk(APIC_VERBOSE, "ENABLING IO-APIC IRQs\n");
2404	for_each_ioapic(ioapic)
2405		BUG_ON(mp_irqdomain_create(ioapic));
2406
2407	/*
2408         * Set up IO-APIC IRQ routing.
2409         */
2410	x86_init.mpparse.setup_ioapic_ids();
2411
2412	sync_Arb_IDs();
2413	setup_IO_APIC_irqs();
2414	init_IO_APIC_traps();
2415	if (nr_legacy_irqs())
2416		check_timer();
2417
2418	ioapic_initialized = 1;
2419}
2420
2421static void resume_ioapic_id(int ioapic_idx)
2422{
2423	unsigned long flags;
2424	union IO_APIC_reg_00 reg_00;
2425
2426	raw_spin_lock_irqsave(&ioapic_lock, flags);
2427	reg_00.raw = io_apic_read(ioapic_idx, 0);
2428	if (reg_00.bits.ID != mpc_ioapic_id(ioapic_idx)) {
2429		reg_00.bits.ID = mpc_ioapic_id(ioapic_idx);
2430		io_apic_write(ioapic_idx, 0, reg_00.raw);
2431	}
2432	raw_spin_unlock_irqrestore(&ioapic_lock, flags);
2433}
2434
2435static void ioapic_resume(void)
2436{
2437	int ioapic_idx;
2438
2439	for_each_ioapic_reverse(ioapic_idx)
2440		resume_ioapic_id(ioapic_idx);
2441
2442	restore_ioapic_entries();
2443}
2444
2445static struct syscore_ops ioapic_syscore_ops = {
2446	.suspend = save_ioapic_entries,
2447	.resume = ioapic_resume,
2448};
2449
2450static int __init ioapic_init_ops(void)
2451{
2452	register_syscore_ops(&ioapic_syscore_ops);
2453
2454	return 0;
2455}
2456
2457device_initcall(ioapic_init_ops);
2458
2459static int io_apic_get_redir_entries(int ioapic)
2460{
2461	union IO_APIC_reg_01	reg_01;
2462	unsigned long flags;
2463
2464	raw_spin_lock_irqsave(&ioapic_lock, flags);
2465	reg_01.raw = io_apic_read(ioapic, 1);
2466	raw_spin_unlock_irqrestore(&ioapic_lock, flags);
2467
2468	/* The register returns the maximum index redir index
2469	 * supported, which is one less than the total number of redir
2470	 * entries.
2471	 */
2472	return reg_01.bits.entries + 1;
2473}
2474
2475unsigned int arch_dynirq_lower_bound(unsigned int from)
2476{
2477	unsigned int ret;
2478
2479	/*
2480	 * dmar_alloc_hwirq() may be called before setup_IO_APIC(), so use
2481	 * gsi_top if ioapic_dynirq_base hasn't been initialized yet.
2482	 */
2483	ret = ioapic_dynirq_base ? : gsi_top;
2484
2485	/*
2486	 * For DT enabled machines ioapic_dynirq_base is irrelevant and
2487	 * always 0. gsi_top can be 0 if there is no IO/APIC registered.
2488	 * 0 is an invalid interrupt number for dynamic allocations. Return
2489	 * @from instead.
2490	 */
2491	return ret ? : from;
2492}
2493
2494#ifdef CONFIG_X86_32
2495static int io_apic_get_unique_id(int ioapic, int apic_id)
2496{
2497	union IO_APIC_reg_00 reg_00;
2498	static physid_mask_t apic_id_map = PHYSID_MASK_NONE;
2499	physid_mask_t tmp;
2500	unsigned long flags;
2501	int i = 0;
2502
2503	/*
2504	 * The P4 platform supports up to 256 APIC IDs on two separate APIC
2505	 * buses (one for LAPICs, one for IOAPICs), where predecessors only
2506	 * supports up to 16 on one shared APIC bus.
2507	 *
2508	 * TBD: Expand LAPIC/IOAPIC support on P4-class systems to take full
2509	 *      advantage of new APIC bus architecture.
2510	 */
2511
2512	if (physids_empty(apic_id_map))
2513		apic->ioapic_phys_id_map(&phys_cpu_present_map, &apic_id_map);
2514
2515	raw_spin_lock_irqsave(&ioapic_lock, flags);
2516	reg_00.raw = io_apic_read(ioapic, 0);
2517	raw_spin_unlock_irqrestore(&ioapic_lock, flags);
2518
2519	if (apic_id >= get_physical_broadcast()) {
2520		printk(KERN_WARNING "IOAPIC[%d]: Invalid apic_id %d, trying "
2521			"%d\n", ioapic, apic_id, reg_00.bits.ID);
2522		apic_id = reg_00.bits.ID;
2523	}
2524
2525	/*
2526	 * Every APIC in a system must have a unique ID or we get lots of nice
2527	 * 'stuck on smp_invalidate_needed IPI wait' messages.
2528	 */
2529	if (apic->check_apicid_used(&apic_id_map, apic_id)) {
2530
2531		for (i = 0; i < get_physical_broadcast(); i++) {
2532			if (!apic->check_apicid_used(&apic_id_map, i))
2533				break;
2534		}
2535
2536		if (i == get_physical_broadcast())
2537			panic("Max apic_id exceeded!\n");
2538
2539		printk(KERN_WARNING "IOAPIC[%d]: apic_id %d already used, "
2540			"trying %d\n", ioapic, apic_id, i);
2541
2542		apic_id = i;
2543	}
2544
2545	physid_set_mask_of_physid(apic_id, &tmp);
2546	physids_or(apic_id_map, apic_id_map, tmp);
2547
2548	if (reg_00.bits.ID != apic_id) {
2549		reg_00.bits.ID = apic_id;
2550
2551		raw_spin_lock_irqsave(&ioapic_lock, flags);
2552		io_apic_write(ioapic, 0, reg_00.raw);
2553		reg_00.raw = io_apic_read(ioapic, 0);
2554		raw_spin_unlock_irqrestore(&ioapic_lock, flags);
2555
2556		/* Sanity check */
2557		if (reg_00.bits.ID != apic_id) {
2558			pr_err("IOAPIC[%d]: Unable to change apic_id!\n",
2559			       ioapic);
2560			return -1;
2561		}
2562	}
2563
2564	apic_printk(APIC_VERBOSE, KERN_INFO
2565			"IOAPIC[%d]: Assigned apic_id %d\n", ioapic, apic_id);
2566
2567	return apic_id;
2568}
2569
2570static u8 io_apic_unique_id(int idx, u8 id)
2571{
2572	if ((boot_cpu_data.x86_vendor == X86_VENDOR_INTEL) &&
2573	    !APIC_XAPIC(boot_cpu_apic_version))
2574		return io_apic_get_unique_id(idx, id);
2575	else
2576		return id;
2577}
2578#else
2579static u8 io_apic_unique_id(int idx, u8 id)
2580{
2581	union IO_APIC_reg_00 reg_00;
2582	DECLARE_BITMAP(used, 256);
2583	unsigned long flags;
2584	u8 new_id;
2585	int i;
2586
2587	bitmap_zero(used, 256);
2588	for_each_ioapic(i)
2589		__set_bit(mpc_ioapic_id(i), used);
2590
2591	/* Hand out the requested id if available */
2592	if (!test_bit(id, used))
2593		return id;
2594
2595	/*
2596	 * Read the current id from the ioapic and keep it if
2597	 * available.
2598	 */
2599	raw_spin_lock_irqsave(&ioapic_lock, flags);
2600	reg_00.raw = io_apic_read(idx, 0);
2601	raw_spin_unlock_irqrestore(&ioapic_lock, flags);
2602	new_id = reg_00.bits.ID;
2603	if (!test_bit(new_id, used)) {
2604		apic_printk(APIC_VERBOSE, KERN_INFO
2605			"IOAPIC[%d]: Using reg apic_id %d instead of %d\n",
2606			 idx, new_id, id);
2607		return new_id;
2608	}
2609
2610	/*
2611	 * Get the next free id and write it to the ioapic.
2612	 */
2613	new_id = find_first_zero_bit(used, 256);
2614	reg_00.bits.ID = new_id;
2615	raw_spin_lock_irqsave(&ioapic_lock, flags);
2616	io_apic_write(idx, 0, reg_00.raw);
2617	reg_00.raw = io_apic_read(idx, 0);
2618	raw_spin_unlock_irqrestore(&ioapic_lock, flags);
2619	/* Sanity check */
2620	BUG_ON(reg_00.bits.ID != new_id);
2621
2622	return new_id;
2623}
2624#endif
2625
2626static int io_apic_get_version(int ioapic)
2627{
2628	union IO_APIC_reg_01	reg_01;
2629	unsigned long flags;
2630
2631	raw_spin_lock_irqsave(&ioapic_lock, flags);
2632	reg_01.raw = io_apic_read(ioapic, 1);
2633	raw_spin_unlock_irqrestore(&ioapic_lock, flags);
2634
2635	return reg_01.bits.version;
2636}
2637
2638/*
2639 * This function updates target affinity of IOAPIC interrupts to include
2640 * the CPUs which came online during SMP bringup.
2641 */
2642#define IOAPIC_RESOURCE_NAME_SIZE 11
2643
2644static struct resource *ioapic_resources;
2645
2646static struct resource * __init ioapic_setup_resources(void)
2647{
2648	unsigned long n;
2649	struct resource *res;
2650	char *mem;
2651	int i;
2652
2653	if (nr_ioapics == 0)
2654		return NULL;
2655
2656	n = IOAPIC_RESOURCE_NAME_SIZE + sizeof(struct resource);
2657	n *= nr_ioapics;
2658
2659	mem = memblock_alloc(n, SMP_CACHE_BYTES);
2660	if (!mem)
2661		panic("%s: Failed to allocate %lu bytes\n", __func__, n);
2662	res = (void *)mem;
2663
2664	mem += sizeof(struct resource) * nr_ioapics;
2665
2666	for_each_ioapic(i) {
2667		res[i].name = mem;
2668		res[i].flags = IORESOURCE_MEM | IORESOURCE_BUSY;
2669		snprintf(mem, IOAPIC_RESOURCE_NAME_SIZE, "IOAPIC %u", i);
2670		mem += IOAPIC_RESOURCE_NAME_SIZE;
2671		ioapics[i].iomem_res = &res[i];
2672	}
2673
2674	ioapic_resources = res;
2675
2676	return res;
2677}
2678
2679static void io_apic_set_fixmap(enum fixed_addresses idx, phys_addr_t phys)
2680{
2681	pgprot_t flags = FIXMAP_PAGE_NOCACHE;
2682
2683	/*
2684	 * Ensure fixmaps for IO-APIC MMIO respect memory encryption pgprot
2685	 * bits, just like normal ioremap():
2686	 */
2687	if (cc_platform_has(CC_ATTR_GUEST_MEM_ENCRYPT)) {
2688		if (x86_platform.hyper.is_private_mmio(phys))
2689			flags = pgprot_encrypted(flags);
2690		else
2691			flags = pgprot_decrypted(flags);
2692	}
2693
2694	__set_fixmap(idx, phys, flags);
2695}
2696
2697void __init io_apic_init_mappings(void)
2698{
2699	unsigned long ioapic_phys, idx = FIX_IO_APIC_BASE_0;
2700	struct resource *ioapic_res;
2701	int i;
2702
2703	ioapic_res = ioapic_setup_resources();
2704	for_each_ioapic(i) {
2705		if (smp_found_config) {
2706			ioapic_phys = mpc_ioapic_addr(i);
2707#ifdef CONFIG_X86_32
2708			if (!ioapic_phys) {
2709				printk(KERN_ERR
2710				       "WARNING: bogus zero IO-APIC "
2711				       "address found in MPTABLE, "
2712				       "disabling IO/APIC support!\n");
2713				smp_found_config = 0;
2714				ioapic_is_disabled = true;
2715				goto fake_ioapic_page;
2716			}
2717#endif
2718		} else {
2719#ifdef CONFIG_X86_32
2720fake_ioapic_page:
2721#endif
2722			ioapic_phys = (unsigned long)memblock_alloc(PAGE_SIZE,
2723								    PAGE_SIZE);
2724			if (!ioapic_phys)
2725				panic("%s: Failed to allocate %lu bytes align=0x%lx\n",
2726				      __func__, PAGE_SIZE, PAGE_SIZE);
2727			ioapic_phys = __pa(ioapic_phys);
2728		}
2729		io_apic_set_fixmap(idx, ioapic_phys);
2730		apic_printk(APIC_VERBOSE, "mapped IOAPIC to %08lx (%08lx)\n",
2731			__fix_to_virt(idx) + (ioapic_phys & ~PAGE_MASK),
2732			ioapic_phys);
2733		idx++;
2734
2735		ioapic_res->start = ioapic_phys;
2736		ioapic_res->end = ioapic_phys + IO_APIC_SLOT_SIZE - 1;
2737		ioapic_res++;
2738	}
2739}
2740
2741void __init ioapic_insert_resources(void)
2742{
2743	int i;
2744	struct resource *r = ioapic_resources;
2745
2746	if (!r) {
2747		if (nr_ioapics > 0)
2748			printk(KERN_ERR
2749				"IO APIC resources couldn't be allocated.\n");
2750		return;
2751	}
2752
2753	for_each_ioapic(i) {
2754		insert_resource(&iomem_resource, r);
2755		r++;
2756	}
2757}
2758
2759int mp_find_ioapic(u32 gsi)
2760{
2761	int i;
2762
2763	if (nr_ioapics == 0)
2764		return -1;
2765
2766	/* Find the IOAPIC that manages this GSI. */
2767	for_each_ioapic(i) {
2768		struct mp_ioapic_gsi *gsi_cfg = mp_ioapic_gsi_routing(i);
2769		if (gsi >= gsi_cfg->gsi_base && gsi <= gsi_cfg->gsi_end)
2770			return i;
2771	}
2772
2773	printk(KERN_ERR "ERROR: Unable to locate IOAPIC for GSI %d\n", gsi);
2774	return -1;
2775}
2776
2777int mp_find_ioapic_pin(int ioapic, u32 gsi)
2778{
2779	struct mp_ioapic_gsi *gsi_cfg;
2780
2781	if (WARN_ON(ioapic < 0))
2782		return -1;
2783
2784	gsi_cfg = mp_ioapic_gsi_routing(ioapic);
2785	if (WARN_ON(gsi > gsi_cfg->gsi_end))
2786		return -1;
2787
2788	return gsi - gsi_cfg->gsi_base;
2789}
2790
2791static int bad_ioapic_register(int idx)
2792{
2793	union IO_APIC_reg_00 reg_00;
2794	union IO_APIC_reg_01 reg_01;
2795	union IO_APIC_reg_02 reg_02;
2796
2797	reg_00.raw = io_apic_read(idx, 0);
2798	reg_01.raw = io_apic_read(idx, 1);
2799	reg_02.raw = io_apic_read(idx, 2);
2800
2801	if (reg_00.raw == -1 && reg_01.raw == -1 && reg_02.raw == -1) {
2802		pr_warn("I/O APIC 0x%x registers return all ones, skipping!\n",
2803			mpc_ioapic_addr(idx));
2804		return 1;
2805	}
2806
2807	return 0;
2808}
2809
2810static int find_free_ioapic_entry(void)
2811{
2812	int idx;
2813
2814	for (idx = 0; idx < MAX_IO_APICS; idx++)
2815		if (ioapics[idx].nr_registers == 0)
2816			return idx;
2817
2818	return MAX_IO_APICS;
2819}
2820
2821/**
2822 * mp_register_ioapic - Register an IOAPIC device
2823 * @id:		hardware IOAPIC ID
2824 * @address:	physical address of IOAPIC register area
2825 * @gsi_base:	base of GSI associated with the IOAPIC
2826 * @cfg:	configuration information for the IOAPIC
2827 */
2828int mp_register_ioapic(int id, u32 address, u32 gsi_base,
2829		       struct ioapic_domain_cfg *cfg)
2830{
2831	bool hotplug = !!ioapic_initialized;
2832	struct mp_ioapic_gsi *gsi_cfg;
2833	int idx, ioapic, entries;
2834	u32 gsi_end;
2835
2836	if (!address) {
2837		pr_warn("Bogus (zero) I/O APIC address found, skipping!\n");
2838		return -EINVAL;
2839	}
2840	for_each_ioapic(ioapic)
2841		if (ioapics[ioapic].mp_config.apicaddr == address) {
2842			pr_warn("address 0x%x conflicts with IOAPIC%d\n",
2843				address, ioapic);
2844			return -EEXIST;
2845		}
2846
2847	idx = find_free_ioapic_entry();
2848	if (idx >= MAX_IO_APICS) {
2849		pr_warn("Max # of I/O APICs (%d) exceeded (found %d), skipping\n",
2850			MAX_IO_APICS, idx);
2851		return -ENOSPC;
2852	}
2853
2854	ioapics[idx].mp_config.type = MP_IOAPIC;
2855	ioapics[idx].mp_config.flags = MPC_APIC_USABLE;
2856	ioapics[idx].mp_config.apicaddr = address;
2857
2858	io_apic_set_fixmap(FIX_IO_APIC_BASE_0 + idx, address);
2859	if (bad_ioapic_register(idx)) {
2860		clear_fixmap(FIX_IO_APIC_BASE_0 + idx);
2861		return -ENODEV;
2862	}
2863
2864	ioapics[idx].mp_config.apicid = io_apic_unique_id(idx, id);
2865	ioapics[idx].mp_config.apicver = io_apic_get_version(idx);
2866
2867	/*
2868	 * Build basic GSI lookup table to facilitate gsi->io_apic lookups
2869	 * and to prevent reprogramming of IOAPIC pins (PCI GSIs).
2870	 */
2871	entries = io_apic_get_redir_entries(idx);
2872	gsi_end = gsi_base + entries - 1;
2873	for_each_ioapic(ioapic) {
2874		gsi_cfg = mp_ioapic_gsi_routing(ioapic);
2875		if ((gsi_base >= gsi_cfg->gsi_base &&
2876		     gsi_base <= gsi_cfg->gsi_end) ||
2877		    (gsi_end >= gsi_cfg->gsi_base &&
2878		     gsi_end <= gsi_cfg->gsi_end)) {
2879			pr_warn("GSI range [%u-%u] for new IOAPIC conflicts with GSI[%u-%u]\n",
2880				gsi_base, gsi_end,
2881				gsi_cfg->gsi_base, gsi_cfg->gsi_end);
2882			clear_fixmap(FIX_IO_APIC_BASE_0 + idx);
2883			return -ENOSPC;
2884		}
2885	}
2886	gsi_cfg = mp_ioapic_gsi_routing(idx);
2887	gsi_cfg->gsi_base = gsi_base;
2888	gsi_cfg->gsi_end = gsi_end;
2889
2890	ioapics[idx].irqdomain = NULL;
2891	ioapics[idx].irqdomain_cfg = *cfg;
2892
2893	/*
2894	 * If mp_register_ioapic() is called during early boot stage when
2895	 * walking ACPI/DT tables, it's too early to create irqdomain,
2896	 * we are still using bootmem allocator. So delay it to setup_IO_APIC().
2897	 */
2898	if (hotplug) {
2899		if (mp_irqdomain_create(idx)) {
2900			clear_fixmap(FIX_IO_APIC_BASE_0 + idx);
2901			return -ENOMEM;
2902		}
2903		alloc_ioapic_saved_registers(idx);
2904	}
2905
2906	if (gsi_cfg->gsi_end >= gsi_top)
2907		gsi_top = gsi_cfg->gsi_end + 1;
2908	if (nr_ioapics <= idx)
2909		nr_ioapics = idx + 1;
2910
2911	/* Set nr_registers to mark entry present */
2912	ioapics[idx].nr_registers = entries;
2913
2914	pr_info("IOAPIC[%d]: apic_id %d, version %d, address 0x%x, GSI %d-%d\n",
2915		idx, mpc_ioapic_id(idx),
2916		mpc_ioapic_ver(idx), mpc_ioapic_addr(idx),
2917		gsi_cfg->gsi_base, gsi_cfg->gsi_end);
2918
2919	return 0;
2920}
2921
2922int mp_unregister_ioapic(u32 gsi_base)
2923{
2924	int ioapic, pin;
2925	int found = 0;
2926
2927	for_each_ioapic(ioapic)
2928		if (ioapics[ioapic].gsi_config.gsi_base == gsi_base) {
2929			found = 1;
2930			break;
2931		}
2932	if (!found) {
2933		pr_warn("can't find IOAPIC for GSI %d\n", gsi_base);
2934		return -ENODEV;
2935	}
2936
2937	for_each_pin(ioapic, pin) {
2938		u32 gsi = mp_pin_to_gsi(ioapic, pin);
2939		int irq = mp_map_gsi_to_irq(gsi, 0, NULL);
2940		struct mp_chip_data *data;
2941
2942		if (irq >= 0) {
2943			data = irq_get_chip_data(irq);
2944			if (data && data->count) {
2945				pr_warn("pin%d on IOAPIC%d is still in use.\n",
2946					pin, ioapic);
2947				return -EBUSY;
2948			}
2949		}
2950	}
2951
2952	/* Mark entry not present */
2953	ioapics[ioapic].nr_registers  = 0;
2954	ioapic_destroy_irqdomain(ioapic);
2955	free_ioapic_saved_registers(ioapic);
2956	if (ioapics[ioapic].iomem_res)
2957		release_resource(ioapics[ioapic].iomem_res);
2958	clear_fixmap(FIX_IO_APIC_BASE_0 + ioapic);
2959	memset(&ioapics[ioapic], 0, sizeof(ioapics[ioapic]));
2960
2961	return 0;
2962}
2963
2964int mp_ioapic_registered(u32 gsi_base)
2965{
2966	int ioapic;
2967
2968	for_each_ioapic(ioapic)
2969		if (ioapics[ioapic].gsi_config.gsi_base == gsi_base)
2970			return 1;
2971
2972	return 0;
2973}
2974
2975static void mp_irqdomain_get_attr(u32 gsi, struct mp_chip_data *data,
2976				  struct irq_alloc_info *info)
2977{
2978	if (info && info->ioapic.valid) {
2979		data->is_level = info->ioapic.is_level;
2980		data->active_low = info->ioapic.active_low;
2981	} else if (__acpi_get_override_irq(gsi, &data->is_level,
2982					   &data->active_low) < 0) {
2983		/* PCI interrupts are always active low level triggered. */
2984		data->is_level = true;
2985		data->active_low = true;
2986	}
2987}
2988
2989/*
2990 * Configure the I/O-APIC specific fields in the routing entry.
2991 *
2992 * This is important to setup the I/O-APIC specific bits (is_level,
2993 * active_low, masked) because the underlying parent domain will only
2994 * provide the routing information and is oblivious of the I/O-APIC
2995 * specific bits.
2996 *
2997 * The entry is just preconfigured at this point and not written into the
2998 * RTE. This happens later during activation which will fill in the actual
2999 * routing information.
3000 */
3001static void mp_preconfigure_entry(struct mp_chip_data *data)
3002{
3003	struct IO_APIC_route_entry *entry = &data->entry;
3004
3005	memset(entry, 0, sizeof(*entry));
3006	entry->is_level		 = data->is_level;
3007	entry->active_low	 = data->active_low;
3008	/*
3009	 * Mask level triggered irqs. Edge triggered irqs are masked
3010	 * by the irq core code in case they fire.
3011	 */
3012	entry->masked		= data->is_level;
3013}
3014
3015int mp_irqdomain_alloc(struct irq_domain *domain, unsigned int virq,
3016		       unsigned int nr_irqs, void *arg)
3017{
3018	struct irq_alloc_info *info = arg;
3019	struct mp_chip_data *data;
3020	struct irq_data *irq_data;
3021	int ret, ioapic, pin;
3022	unsigned long flags;
3023
3024	if (!info || nr_irqs > 1)
3025		return -EINVAL;
3026	irq_data = irq_domain_get_irq_data(domain, virq);
3027	if (!irq_data)
3028		return -EINVAL;
3029
3030	ioapic = mp_irqdomain_ioapic_idx(domain);
3031	pin = info->ioapic.pin;
3032	if (irq_find_mapping(domain, (irq_hw_number_t)pin) > 0)
3033		return -EEXIST;
3034
3035	data = kzalloc(sizeof(*data), GFP_KERNEL);
3036	if (!data)
3037		return -ENOMEM;
3038
3039	ret = irq_domain_alloc_irqs_parent(domain, virq, nr_irqs, info);
3040	if (ret < 0) {
3041		kfree(data);
3042		return ret;
3043	}
3044
3045	INIT_LIST_HEAD(&data->irq_2_pin);
3046	irq_data->hwirq = info->ioapic.pin;
3047	irq_data->chip = (domain->parent == x86_vector_domain) ?
3048			  &ioapic_chip : &ioapic_ir_chip;
3049	irq_data->chip_data = data;
3050	mp_irqdomain_get_attr(mp_pin_to_gsi(ioapic, pin), data, info);
3051
3052	add_pin_to_irq_node(data, ioapic_alloc_attr_node(info), ioapic, pin);
3053
3054	mp_preconfigure_entry(data);
3055	mp_register_handler(virq, data->is_level);
3056
3057	local_irq_save(flags);
3058	if (virq < nr_legacy_irqs())
3059		legacy_pic->mask(virq);
3060	local_irq_restore(flags);
3061
3062	apic_printk(APIC_VERBOSE, KERN_DEBUG
3063		    "IOAPIC[%d]: Preconfigured routing entry (%d-%d -> IRQ %d Level:%i ActiveLow:%i)\n",
3064		    ioapic, mpc_ioapic_id(ioapic), pin, virq,
3065		    data->is_level, data->active_low);
3066	return 0;
3067}
3068
3069void mp_irqdomain_free(struct irq_domain *domain, unsigned int virq,
3070		       unsigned int nr_irqs)
3071{
3072	struct irq_data *irq_data;
3073	struct mp_chip_data *data;
3074
3075	BUG_ON(nr_irqs != 1);
3076	irq_data = irq_domain_get_irq_data(domain, virq);
3077	if (irq_data && irq_data->chip_data) {
3078		data = irq_data->chip_data;
3079		__remove_pin_from_irq(data, mp_irqdomain_ioapic_idx(domain),
3080				      (int)irq_data->hwirq);
3081		WARN_ON(!list_empty(&data->irq_2_pin));
3082		kfree(irq_data->chip_data);
3083	}
3084	irq_domain_free_irqs_top(domain, virq, nr_irqs);
3085}
3086
3087int mp_irqdomain_activate(struct irq_domain *domain,
3088			  struct irq_data *irq_data, bool reserve)
3089{
3090	unsigned long flags;
3091
3092	raw_spin_lock_irqsave(&ioapic_lock, flags);
3093	ioapic_configure_entry(irq_data);
3094	raw_spin_unlock_irqrestore(&ioapic_lock, flags);
3095	return 0;
3096}
3097
3098void mp_irqdomain_deactivate(struct irq_domain *domain,
3099			     struct irq_data *irq_data)
3100{
3101	/* It won't be called for IRQ with multiple IOAPIC pins associated */
3102	ioapic_mask_entry(mp_irqdomain_ioapic_idx(domain),
3103			  (int)irq_data->hwirq);
3104}
3105
3106int mp_irqdomain_ioapic_idx(struct irq_domain *domain)
3107{
3108	return (int)(long)domain->host_data;
3109}
3110
3111const struct irq_domain_ops mp_ioapic_irqdomain_ops = {
3112	.alloc		= mp_irqdomain_alloc,
3113	.free		= mp_irqdomain_free,
3114	.activate	= mp_irqdomain_activate,
3115	.deactivate	= mp_irqdomain_deactivate,
3116};
v5.14.15
   1// SPDX-License-Identifier: GPL-2.0
   2/*
   3 *	Intel IO-APIC support for multi-Pentium hosts.
   4 *
   5 *	Copyright (C) 1997, 1998, 1999, 2000, 2009 Ingo Molnar, Hajnalka Szabo
   6 *
   7 *	Many thanks to Stig Venaas for trying out countless experimental
   8 *	patches and reporting/debugging problems patiently!
   9 *
  10 *	(c) 1999, Multiple IO-APIC support, developed by
  11 *	Ken-ichi Yaku <yaku@css1.kbnes.nec.co.jp> and
  12 *      Hidemi Kishimoto <kisimoto@css1.kbnes.nec.co.jp>,
  13 *	further tested and cleaned up by Zach Brown <zab@redhat.com>
  14 *	and Ingo Molnar <mingo@redhat.com>
  15 *
  16 *	Fixes
  17 *	Maciej W. Rozycki	:	Bits for genuine 82489DX APICs;
  18 *					thanks to Eric Gilmore
  19 *					and Rolf G. Tews
  20 *					for testing these extensively
  21 *	Paul Diefenbaugh	:	Added full ACPI support
  22 *
  23 * Historical information which is worth to be preserved:
  24 *
  25 * - SiS APIC rmw bug:
  26 *
  27 *	We used to have a workaround for a bug in SiS chips which
  28 *	required to rewrite the index register for a read-modify-write
  29 *	operation as the chip lost the index information which was
  30 *	setup for the read already. We cache the data now, so that
  31 *	workaround has been removed.
  32 */
  33
  34#include <linux/mm.h>
  35#include <linux/interrupt.h>
  36#include <linux/irq.h>
  37#include <linux/init.h>
  38#include <linux/delay.h>
  39#include <linux/sched.h>
  40#include <linux/pci.h>
  41#include <linux/mc146818rtc.h>
  42#include <linux/compiler.h>
  43#include <linux/acpi.h>
  44#include <linux/export.h>
  45#include <linux/syscore_ops.h>
  46#include <linux/freezer.h>
  47#include <linux/kthread.h>
  48#include <linux/jiffies.h>	/* time_after() */
  49#include <linux/slab.h>
  50#include <linux/memblock.h>
  51#include <linux/msi.h>
  52
  53#include <asm/irqdomain.h>
  54#include <asm/io.h>
  55#include <asm/smp.h>
  56#include <asm/cpu.h>
  57#include <asm/desc.h>
  58#include <asm/proto.h>
  59#include <asm/acpi.h>
  60#include <asm/dma.h>
  61#include <asm/timer.h>
  62#include <asm/time.h>
  63#include <asm/i8259.h>
  64#include <asm/setup.h>
  65#include <asm/irq_remapping.h>
  66#include <asm/hw_irq.h>
  67#include <asm/apic.h>
 
 
  68
  69#define	for_each_ioapic(idx)		\
  70	for ((idx) = 0; (idx) < nr_ioapics; (idx)++)
  71#define	for_each_ioapic_reverse(idx)	\
  72	for ((idx) = nr_ioapics - 1; (idx) >= 0; (idx)--)
  73#define	for_each_pin(idx, pin)		\
  74	for ((pin) = 0; (pin) < ioapics[(idx)].nr_registers; (pin)++)
  75#define	for_each_ioapic_pin(idx, pin)	\
  76	for_each_ioapic((idx))		\
  77		for_each_pin((idx), (pin))
  78#define for_each_irq_pin(entry, head) \
  79	list_for_each_entry(entry, &head, list)
  80
  81static DEFINE_RAW_SPINLOCK(ioapic_lock);
  82static DEFINE_MUTEX(ioapic_mutex);
  83static unsigned int ioapic_dynirq_base;
  84static int ioapic_initialized;
  85
  86struct irq_pin_list {
  87	struct list_head list;
  88	int apic, pin;
  89};
  90
  91struct mp_chip_data {
  92	struct list_head		irq_2_pin;
  93	struct IO_APIC_route_entry	entry;
  94	bool				is_level;
  95	bool				active_low;
  96	bool				isa_irq;
  97	u32 count;
  98};
  99
 100struct mp_ioapic_gsi {
 101	u32 gsi_base;
 102	u32 gsi_end;
 103};
 104
 105static struct ioapic {
 106	/*
 107	 * # of IRQ routing registers
 108	 */
 109	int nr_registers;
 110	/*
 111	 * Saved state during suspend/resume, or while enabling intr-remap.
 112	 */
 113	struct IO_APIC_route_entry *saved_registers;
 114	/* I/O APIC config */
 115	struct mpc_ioapic mp_config;
 116	/* IO APIC gsi routing info */
 117	struct mp_ioapic_gsi  gsi_config;
 118	struct ioapic_domain_cfg irqdomain_cfg;
 119	struct irq_domain *irqdomain;
 120	struct resource *iomem_res;
 121} ioapics[MAX_IO_APICS];
 122
 123#define mpc_ioapic_ver(ioapic_idx)	ioapics[ioapic_idx].mp_config.apicver
 124
 125int mpc_ioapic_id(int ioapic_idx)
 126{
 127	return ioapics[ioapic_idx].mp_config.apicid;
 128}
 129
 130unsigned int mpc_ioapic_addr(int ioapic_idx)
 131{
 132	return ioapics[ioapic_idx].mp_config.apicaddr;
 133}
 134
 135static inline struct mp_ioapic_gsi *mp_ioapic_gsi_routing(int ioapic_idx)
 136{
 137	return &ioapics[ioapic_idx].gsi_config;
 138}
 139
 140static inline int mp_ioapic_pin_count(int ioapic)
 141{
 142	struct mp_ioapic_gsi *gsi_cfg = mp_ioapic_gsi_routing(ioapic);
 143
 144	return gsi_cfg->gsi_end - gsi_cfg->gsi_base + 1;
 145}
 146
 147static inline u32 mp_pin_to_gsi(int ioapic, int pin)
 148{
 149	return mp_ioapic_gsi_routing(ioapic)->gsi_base + pin;
 150}
 151
 152static inline bool mp_is_legacy_irq(int irq)
 153{
 154	return irq >= 0 && irq < nr_legacy_irqs();
 155}
 156
 157static inline struct irq_domain *mp_ioapic_irqdomain(int ioapic)
 158{
 159	return ioapics[ioapic].irqdomain;
 160}
 161
 162int nr_ioapics;
 163
 164/* The one past the highest gsi number used */
 165u32 gsi_top;
 166
 167/* MP IRQ source entries */
 168struct mpc_intsrc mp_irqs[MAX_IRQ_SOURCES];
 169
 170/* # of MP IRQ source entries */
 171int mp_irq_entries;
 172
 173#ifdef CONFIG_EISA
 174int mp_bus_id_to_type[MAX_MP_BUSSES];
 175#endif
 176
 177DECLARE_BITMAP(mp_bus_not_pci, MAX_MP_BUSSES);
 178
 179int skip_ioapic_setup;
 180
 181/**
 182 * disable_ioapic_support() - disables ioapic support at runtime
 183 */
 184void disable_ioapic_support(void)
 185{
 186#ifdef CONFIG_PCI
 187	noioapicquirk = 1;
 188	noioapicreroute = -1;
 189#endif
 190	skip_ioapic_setup = 1;
 191}
 192
 193static int __init parse_noapic(char *str)
 194{
 195	/* disable IO-APIC */
 196	disable_ioapic_support();
 197	return 0;
 198}
 199early_param("noapic", parse_noapic);
 200
 201/* Will be called in mpparse/ACPI codes for saving IRQ info */
 202void mp_save_irq(struct mpc_intsrc *m)
 203{
 204	int i;
 205
 206	apic_printk(APIC_VERBOSE, "Int: type %d, pol %d, trig %d, bus %02x,"
 207		" IRQ %02x, APIC ID %x, APIC INT %02x\n",
 208		m->irqtype, m->irqflag & 3, (m->irqflag >> 2) & 3, m->srcbus,
 209		m->srcbusirq, m->dstapic, m->dstirq);
 210
 211	for (i = 0; i < mp_irq_entries; i++) {
 212		if (!memcmp(&mp_irqs[i], m, sizeof(*m)))
 213			return;
 214	}
 215
 216	memcpy(&mp_irqs[mp_irq_entries], m, sizeof(*m));
 217	if (++mp_irq_entries == MAX_IRQ_SOURCES)
 218		panic("Max # of irq sources exceeded!!\n");
 219}
 220
 221static void alloc_ioapic_saved_registers(int idx)
 222{
 223	size_t size;
 224
 225	if (ioapics[idx].saved_registers)
 226		return;
 227
 228	size = sizeof(struct IO_APIC_route_entry) * ioapics[idx].nr_registers;
 229	ioapics[idx].saved_registers = kzalloc(size, GFP_KERNEL);
 230	if (!ioapics[idx].saved_registers)
 231		pr_err("IOAPIC %d: suspend/resume impossible!\n", idx);
 232}
 233
 234static void free_ioapic_saved_registers(int idx)
 235{
 236	kfree(ioapics[idx].saved_registers);
 237	ioapics[idx].saved_registers = NULL;
 238}
 239
 240int __init arch_early_ioapic_init(void)
 241{
 242	int i;
 243
 244	if (!nr_legacy_irqs())
 245		io_apic_irqs = ~0UL;
 246
 247	for_each_ioapic(i)
 248		alloc_ioapic_saved_registers(i);
 249
 250	return 0;
 251}
 252
 253struct io_apic {
 254	unsigned int index;
 255	unsigned int unused[3];
 256	unsigned int data;
 257	unsigned int unused2[11];
 258	unsigned int eoi;
 259};
 260
 261static __attribute_const__ struct io_apic __iomem *io_apic_base(int idx)
 262{
 263	return (void __iomem *) __fix_to_virt(FIX_IO_APIC_BASE_0 + idx)
 264		+ (mpc_ioapic_addr(idx) & ~PAGE_MASK);
 265}
 266
 267static inline void io_apic_eoi(unsigned int apic, unsigned int vector)
 268{
 269	struct io_apic __iomem *io_apic = io_apic_base(apic);
 270	writel(vector, &io_apic->eoi);
 271}
 272
 273unsigned int native_io_apic_read(unsigned int apic, unsigned int reg)
 274{
 275	struct io_apic __iomem *io_apic = io_apic_base(apic);
 276	writel(reg, &io_apic->index);
 277	return readl(&io_apic->data);
 278}
 279
 280static void io_apic_write(unsigned int apic, unsigned int reg,
 281			  unsigned int value)
 282{
 283	struct io_apic __iomem *io_apic = io_apic_base(apic);
 284
 285	writel(reg, &io_apic->index);
 286	writel(value, &io_apic->data);
 287}
 288
 289static struct IO_APIC_route_entry __ioapic_read_entry(int apic, int pin)
 290{
 291	struct IO_APIC_route_entry entry;
 292
 293	entry.w1 = io_apic_read(apic, 0x10 + 2 * pin);
 294	entry.w2 = io_apic_read(apic, 0x11 + 2 * pin);
 295
 296	return entry;
 297}
 298
 299static struct IO_APIC_route_entry ioapic_read_entry(int apic, int pin)
 300{
 301	struct IO_APIC_route_entry entry;
 302	unsigned long flags;
 303
 304	raw_spin_lock_irqsave(&ioapic_lock, flags);
 305	entry = __ioapic_read_entry(apic, pin);
 306	raw_spin_unlock_irqrestore(&ioapic_lock, flags);
 307
 308	return entry;
 309}
 310
 311/*
 312 * When we write a new IO APIC routing entry, we need to write the high
 313 * word first! If the mask bit in the low word is clear, we will enable
 314 * the interrupt, and we need to make sure the entry is fully populated
 315 * before that happens.
 316 */
 317static void __ioapic_write_entry(int apic, int pin, struct IO_APIC_route_entry e)
 318{
 319	io_apic_write(apic, 0x11 + 2*pin, e.w2);
 320	io_apic_write(apic, 0x10 + 2*pin, e.w1);
 321}
 322
 323static void ioapic_write_entry(int apic, int pin, struct IO_APIC_route_entry e)
 324{
 325	unsigned long flags;
 326
 327	raw_spin_lock_irqsave(&ioapic_lock, flags);
 328	__ioapic_write_entry(apic, pin, e);
 329	raw_spin_unlock_irqrestore(&ioapic_lock, flags);
 330}
 331
 332/*
 333 * When we mask an IO APIC routing entry, we need to write the low
 334 * word first, in order to set the mask bit before we change the
 335 * high bits!
 336 */
 337static void ioapic_mask_entry(int apic, int pin)
 338{
 339	struct IO_APIC_route_entry e = { .masked = true };
 340	unsigned long flags;
 341
 342	raw_spin_lock_irqsave(&ioapic_lock, flags);
 343	io_apic_write(apic, 0x10 + 2*pin, e.w1);
 344	io_apic_write(apic, 0x11 + 2*pin, e.w2);
 345	raw_spin_unlock_irqrestore(&ioapic_lock, flags);
 346}
 347
 348/*
 349 * The common case is 1:1 IRQ<->pin mappings. Sometimes there are
 350 * shared ISA-space IRQs, so we have to support them. We are super
 351 * fast in the common case, and fast for shared ISA-space IRQs.
 352 */
 353static int __add_pin_to_irq_node(struct mp_chip_data *data,
 354				 int node, int apic, int pin)
 355{
 356	struct irq_pin_list *entry;
 357
 358	/* don't allow duplicates */
 359	for_each_irq_pin(entry, data->irq_2_pin)
 360		if (entry->apic == apic && entry->pin == pin)
 361			return 0;
 362
 363	entry = kzalloc_node(sizeof(struct irq_pin_list), GFP_ATOMIC, node);
 364	if (!entry) {
 365		pr_err("can not alloc irq_pin_list (%d,%d,%d)\n",
 366		       node, apic, pin);
 367		return -ENOMEM;
 368	}
 369	entry->apic = apic;
 370	entry->pin = pin;
 371	list_add_tail(&entry->list, &data->irq_2_pin);
 372
 373	return 0;
 374}
 375
 376static void __remove_pin_from_irq(struct mp_chip_data *data, int apic, int pin)
 377{
 378	struct irq_pin_list *tmp, *entry;
 379
 380	list_for_each_entry_safe(entry, tmp, &data->irq_2_pin, list)
 381		if (entry->apic == apic && entry->pin == pin) {
 382			list_del(&entry->list);
 383			kfree(entry);
 384			return;
 385		}
 386}
 387
 388static void add_pin_to_irq_node(struct mp_chip_data *data,
 389				int node, int apic, int pin)
 390{
 391	if (__add_pin_to_irq_node(data, node, apic, pin))
 392		panic("IO-APIC: failed to add irq-pin. Can not proceed\n");
 393}
 394
 395/*
 396 * Reroute an IRQ to a different pin.
 397 */
 398static void __init replace_pin_at_irq_node(struct mp_chip_data *data, int node,
 399					   int oldapic, int oldpin,
 400					   int newapic, int newpin)
 401{
 402	struct irq_pin_list *entry;
 403
 404	for_each_irq_pin(entry, data->irq_2_pin) {
 405		if (entry->apic == oldapic && entry->pin == oldpin) {
 406			entry->apic = newapic;
 407			entry->pin = newpin;
 408			/* every one is different, right? */
 409			return;
 410		}
 411	}
 412
 413	/* old apic/pin didn't exist, so just add new ones */
 414	add_pin_to_irq_node(data, node, newapic, newpin);
 415}
 416
 417static void io_apic_modify_irq(struct mp_chip_data *data, bool masked,
 418			       void (*final)(struct irq_pin_list *entry))
 419{
 420	struct irq_pin_list *entry;
 421
 422	data->entry.masked = masked;
 423
 424	for_each_irq_pin(entry, data->irq_2_pin) {
 425		io_apic_write(entry->apic, 0x10 + 2 * entry->pin, data->entry.w1);
 426		if (final)
 427			final(entry);
 428	}
 429}
 430
 431static void io_apic_sync(struct irq_pin_list *entry)
 432{
 433	/*
 434	 * Synchronize the IO-APIC and the CPU by doing
 435	 * a dummy read from the IO-APIC
 436	 */
 437	struct io_apic __iomem *io_apic;
 438
 439	io_apic = io_apic_base(entry->apic);
 440	readl(&io_apic->data);
 441}
 442
 443static void mask_ioapic_irq(struct irq_data *irq_data)
 444{
 445	struct mp_chip_data *data = irq_data->chip_data;
 446	unsigned long flags;
 447
 448	raw_spin_lock_irqsave(&ioapic_lock, flags);
 449	io_apic_modify_irq(data, true, &io_apic_sync);
 450	raw_spin_unlock_irqrestore(&ioapic_lock, flags);
 451}
 452
 453static void __unmask_ioapic(struct mp_chip_data *data)
 454{
 455	io_apic_modify_irq(data, false, NULL);
 456}
 457
 458static void unmask_ioapic_irq(struct irq_data *irq_data)
 459{
 460	struct mp_chip_data *data = irq_data->chip_data;
 461	unsigned long flags;
 462
 463	raw_spin_lock_irqsave(&ioapic_lock, flags);
 464	__unmask_ioapic(data);
 465	raw_spin_unlock_irqrestore(&ioapic_lock, flags);
 466}
 467
 468/*
 469 * IO-APIC versions below 0x20 don't support EOI register.
 470 * For the record, here is the information about various versions:
 471 *     0Xh     82489DX
 472 *     1Xh     I/OAPIC or I/O(x)APIC which are not PCI 2.2 Compliant
 473 *     2Xh     I/O(x)APIC which is PCI 2.2 Compliant
 474 *     30h-FFh Reserved
 475 *
 476 * Some of the Intel ICH Specs (ICH2 to ICH5) documents the io-apic
 477 * version as 0x2. This is an error with documentation and these ICH chips
 478 * use io-apic's of version 0x20.
 479 *
 480 * For IO-APIC's with EOI register, we use that to do an explicit EOI.
 481 * Otherwise, we simulate the EOI message manually by changing the trigger
 482 * mode to edge and then back to level, with RTE being masked during this.
 483 */
 484static void __eoi_ioapic_pin(int apic, int pin, int vector)
 485{
 486	if (mpc_ioapic_ver(apic) >= 0x20) {
 487		io_apic_eoi(apic, vector);
 488	} else {
 489		struct IO_APIC_route_entry entry, entry1;
 490
 491		entry = entry1 = __ioapic_read_entry(apic, pin);
 492
 493		/*
 494		 * Mask the entry and change the trigger mode to edge.
 495		 */
 496		entry1.masked = true;
 497		entry1.is_level = false;
 498
 499		__ioapic_write_entry(apic, pin, entry1);
 500
 501		/*
 502		 * Restore the previous level triggered entry.
 503		 */
 504		__ioapic_write_entry(apic, pin, entry);
 505	}
 506}
 507
 508static void eoi_ioapic_pin(int vector, struct mp_chip_data *data)
 509{
 510	unsigned long flags;
 511	struct irq_pin_list *entry;
 512
 513	raw_spin_lock_irqsave(&ioapic_lock, flags);
 514	for_each_irq_pin(entry, data->irq_2_pin)
 515		__eoi_ioapic_pin(entry->apic, entry->pin, vector);
 516	raw_spin_unlock_irqrestore(&ioapic_lock, flags);
 517}
 518
 519static void clear_IO_APIC_pin(unsigned int apic, unsigned int pin)
 520{
 521	struct IO_APIC_route_entry entry;
 522
 523	/* Check delivery_mode to be sure we're not clearing an SMI pin */
 524	entry = ioapic_read_entry(apic, pin);
 525	if (entry.delivery_mode == APIC_DELIVERY_MODE_SMI)
 526		return;
 527
 528	/*
 529	 * Make sure the entry is masked and re-read the contents to check
 530	 * if it is a level triggered pin and if the remote-IRR is set.
 531	 */
 532	if (!entry.masked) {
 533		entry.masked = true;
 534		ioapic_write_entry(apic, pin, entry);
 535		entry = ioapic_read_entry(apic, pin);
 536	}
 537
 538	if (entry.irr) {
 539		unsigned long flags;
 540
 541		/*
 542		 * Make sure the trigger mode is set to level. Explicit EOI
 543		 * doesn't clear the remote-IRR if the trigger mode is not
 544		 * set to level.
 545		 */
 546		if (!entry.is_level) {
 547			entry.is_level = true;
 548			ioapic_write_entry(apic, pin, entry);
 549		}
 550		raw_spin_lock_irqsave(&ioapic_lock, flags);
 551		__eoi_ioapic_pin(apic, pin, entry.vector);
 552		raw_spin_unlock_irqrestore(&ioapic_lock, flags);
 553	}
 554
 555	/*
 556	 * Clear the rest of the bits in the IO-APIC RTE except for the mask
 557	 * bit.
 558	 */
 559	ioapic_mask_entry(apic, pin);
 560	entry = ioapic_read_entry(apic, pin);
 561	if (entry.irr)
 562		pr_err("Unable to reset IRR for apic: %d, pin :%d\n",
 563		       mpc_ioapic_id(apic), pin);
 564}
 565
 566void clear_IO_APIC (void)
 567{
 568	int apic, pin;
 569
 570	for_each_ioapic_pin(apic, pin)
 571		clear_IO_APIC_pin(apic, pin);
 572}
 573
 574#ifdef CONFIG_X86_32
 575/*
 576 * support for broken MP BIOSs, enables hand-redirection of PIRQ0-7 to
 577 * specific CPU-side IRQs.
 578 */
 579
 580#define MAX_PIRQS 8
 581static int pirq_entries[MAX_PIRQS] = {
 582	[0 ... MAX_PIRQS - 1] = -1
 583};
 584
 585static int __init ioapic_pirq_setup(char *str)
 586{
 587	int i, max;
 588	int ints[MAX_PIRQS+1];
 589
 590	get_options(str, ARRAY_SIZE(ints), ints);
 591
 592	apic_printk(APIC_VERBOSE, KERN_INFO
 593			"PIRQ redirection, working around broken MP-BIOS.\n");
 594	max = MAX_PIRQS;
 595	if (ints[0] < MAX_PIRQS)
 596		max = ints[0];
 597
 598	for (i = 0; i < max; i++) {
 599		apic_printk(APIC_VERBOSE, KERN_DEBUG
 600				"... PIRQ%d -> IRQ %d\n", i, ints[i+1]);
 601		/*
 602		 * PIRQs are mapped upside down, usually.
 603		 */
 604		pirq_entries[MAX_PIRQS-i-1] = ints[i+1];
 605	}
 606	return 1;
 607}
 608
 609__setup("pirq=", ioapic_pirq_setup);
 610#endif /* CONFIG_X86_32 */
 611
 612/*
 613 * Saves all the IO-APIC RTE's
 614 */
 615int save_ioapic_entries(void)
 616{
 617	int apic, pin;
 618	int err = 0;
 619
 620	for_each_ioapic(apic) {
 621		if (!ioapics[apic].saved_registers) {
 622			err = -ENOMEM;
 623			continue;
 624		}
 625
 626		for_each_pin(apic, pin)
 627			ioapics[apic].saved_registers[pin] =
 628				ioapic_read_entry(apic, pin);
 629	}
 630
 631	return err;
 632}
 633
 634/*
 635 * Mask all IO APIC entries.
 636 */
 637void mask_ioapic_entries(void)
 638{
 639	int apic, pin;
 640
 641	for_each_ioapic(apic) {
 642		if (!ioapics[apic].saved_registers)
 643			continue;
 644
 645		for_each_pin(apic, pin) {
 646			struct IO_APIC_route_entry entry;
 647
 648			entry = ioapics[apic].saved_registers[pin];
 649			if (!entry.masked) {
 650				entry.masked = true;
 651				ioapic_write_entry(apic, pin, entry);
 652			}
 653		}
 654	}
 655}
 656
 657/*
 658 * Restore IO APIC entries which was saved in the ioapic structure.
 659 */
 660int restore_ioapic_entries(void)
 661{
 662	int apic, pin;
 663
 664	for_each_ioapic(apic) {
 665		if (!ioapics[apic].saved_registers)
 666			continue;
 667
 668		for_each_pin(apic, pin)
 669			ioapic_write_entry(apic, pin,
 670					   ioapics[apic].saved_registers[pin]);
 671	}
 672	return 0;
 673}
 674
 675/*
 676 * Find the IRQ entry number of a certain pin.
 677 */
 678static int find_irq_entry(int ioapic_idx, int pin, int type)
 679{
 680	int i;
 681
 682	for (i = 0; i < mp_irq_entries; i++)
 683		if (mp_irqs[i].irqtype == type &&
 684		    (mp_irqs[i].dstapic == mpc_ioapic_id(ioapic_idx) ||
 685		     mp_irqs[i].dstapic == MP_APIC_ALL) &&
 686		    mp_irqs[i].dstirq == pin)
 687			return i;
 688
 689	return -1;
 690}
 691
 692/*
 693 * Find the pin to which IRQ[irq] (ISA) is connected
 694 */
 695static int __init find_isa_irq_pin(int irq, int type)
 696{
 697	int i;
 698
 699	for (i = 0; i < mp_irq_entries; i++) {
 700		int lbus = mp_irqs[i].srcbus;
 701
 702		if (test_bit(lbus, mp_bus_not_pci) &&
 703		    (mp_irqs[i].irqtype == type) &&
 704		    (mp_irqs[i].srcbusirq == irq))
 705
 706			return mp_irqs[i].dstirq;
 707	}
 708	return -1;
 709}
 710
 711static int __init find_isa_irq_apic(int irq, int type)
 712{
 713	int i;
 714
 715	for (i = 0; i < mp_irq_entries; i++) {
 716		int lbus = mp_irqs[i].srcbus;
 717
 718		if (test_bit(lbus, mp_bus_not_pci) &&
 719		    (mp_irqs[i].irqtype == type) &&
 720		    (mp_irqs[i].srcbusirq == irq))
 721			break;
 722	}
 723
 724	if (i < mp_irq_entries) {
 725		int ioapic_idx;
 726
 727		for_each_ioapic(ioapic_idx)
 728			if (mpc_ioapic_id(ioapic_idx) == mp_irqs[i].dstapic)
 729				return ioapic_idx;
 730	}
 731
 732	return -1;
 733}
 734
 735static bool irq_active_low(int idx)
 736{
 737	int bus = mp_irqs[idx].srcbus;
 738
 739	/*
 740	 * Determine IRQ line polarity (high active or low active):
 741	 */
 742	switch (mp_irqs[idx].irqflag & MP_IRQPOL_MASK) {
 743	case MP_IRQPOL_DEFAULT:
 744		/*
 745		 * Conforms to spec, ie. bus-type dependent polarity.  PCI
 746		 * defaults to low active. [E]ISA defaults to high active.
 747		 */
 748		return !test_bit(bus, mp_bus_not_pci);
 749	case MP_IRQPOL_ACTIVE_HIGH:
 750		return false;
 751	case MP_IRQPOL_RESERVED:
 752		pr_warn("IOAPIC: Invalid polarity: 2, defaulting to low\n");
 753		fallthrough;
 754	case MP_IRQPOL_ACTIVE_LOW:
 755	default: /* Pointless default required due to do gcc stupidity */
 756		return true;
 757	}
 758}
 759
 760#ifdef CONFIG_EISA
 761/*
 762 * EISA Edge/Level control register, ELCR
 763 */
 764static bool EISA_ELCR(unsigned int irq)
 765{
 766	if (irq < nr_legacy_irqs()) {
 767		unsigned int port = 0x4d0 + (irq >> 3);
 768		return (inb(port) >> (irq & 7)) & 1;
 769	}
 770	apic_printk(APIC_VERBOSE, KERN_INFO
 771			"Broken MPtable reports ISA irq %d\n", irq);
 772	return false;
 773}
 774
 775/*
 776 * EISA interrupts are always active high and can be edge or level
 777 * triggered depending on the ELCR value.  If an interrupt is listed as
 778 * EISA conforming in the MP table, that means its trigger type must be
 779 * read in from the ELCR.
 780 */
 781static bool eisa_irq_is_level(int idx, int bus, bool level)
 782{
 783	switch (mp_bus_id_to_type[bus]) {
 784	case MP_BUS_PCI:
 785	case MP_BUS_ISA:
 786		return level;
 787	case MP_BUS_EISA:
 788		return EISA_ELCR(mp_irqs[idx].srcbusirq);
 789	}
 790	pr_warn("IOAPIC: Invalid srcbus: %d defaulting to level\n", bus);
 791	return true;
 792}
 793#else
 794static inline int eisa_irq_is_level(int idx, int bus, bool level)
 795{
 796	return level;
 797}
 798#endif
 799
 800static bool irq_is_level(int idx)
 801{
 802	int bus = mp_irqs[idx].srcbus;
 803	bool level;
 804
 805	/*
 806	 * Determine IRQ trigger mode (edge or level sensitive):
 807	 */
 808	switch (mp_irqs[idx].irqflag & MP_IRQTRIG_MASK) {
 809	case MP_IRQTRIG_DEFAULT:
 810		/*
 811		 * Conforms to spec, ie. bus-type dependent trigger
 812		 * mode. PCI defaults to level, ISA to edge.
 813		 */
 814		level = !test_bit(bus, mp_bus_not_pci);
 815		/* Take EISA into account */
 816		return eisa_irq_is_level(idx, bus, level);
 817	case MP_IRQTRIG_EDGE:
 818		return false;
 819	case MP_IRQTRIG_RESERVED:
 820		pr_warn("IOAPIC: Invalid trigger mode 2 defaulting to level\n");
 821		fallthrough;
 822	case MP_IRQTRIG_LEVEL:
 823	default: /* Pointless default required due to do gcc stupidity */
 824		return true;
 825	}
 826}
 827
 828static int __acpi_get_override_irq(u32 gsi, bool *trigger, bool *polarity)
 829{
 830	int ioapic, pin, idx;
 831
 832	if (skip_ioapic_setup)
 833		return -1;
 834
 835	ioapic = mp_find_ioapic(gsi);
 836	if (ioapic < 0)
 837		return -1;
 838
 839	pin = mp_find_ioapic_pin(ioapic, gsi);
 840	if (pin < 0)
 841		return -1;
 842
 843	idx = find_irq_entry(ioapic, pin, mp_INT);
 844	if (idx < 0)
 845		return -1;
 846
 847	*trigger = irq_is_level(idx);
 848	*polarity = irq_active_low(idx);
 849	return 0;
 850}
 851
 852#ifdef CONFIG_ACPI
 853int acpi_get_override_irq(u32 gsi, int *is_level, int *active_low)
 854{
 855	*is_level = *active_low = 0;
 856	return __acpi_get_override_irq(gsi, (bool *)is_level,
 857				       (bool *)active_low);
 858}
 859#endif
 860
 861void ioapic_set_alloc_attr(struct irq_alloc_info *info, int node,
 862			   int trigger, int polarity)
 863{
 864	init_irq_alloc_info(info, NULL);
 865	info->type = X86_IRQ_ALLOC_TYPE_IOAPIC;
 866	info->ioapic.node = node;
 867	info->ioapic.is_level = trigger;
 868	info->ioapic.active_low = polarity;
 869	info->ioapic.valid = 1;
 870}
 871
 872static void ioapic_copy_alloc_attr(struct irq_alloc_info *dst,
 873				   struct irq_alloc_info *src,
 874				   u32 gsi, int ioapic_idx, int pin)
 875{
 876	bool level, pol_low;
 877
 878	copy_irq_alloc_info(dst, src);
 879	dst->type = X86_IRQ_ALLOC_TYPE_IOAPIC;
 880	dst->devid = mpc_ioapic_id(ioapic_idx);
 881	dst->ioapic.pin = pin;
 882	dst->ioapic.valid = 1;
 883	if (src && src->ioapic.valid) {
 884		dst->ioapic.node = src->ioapic.node;
 885		dst->ioapic.is_level = src->ioapic.is_level;
 886		dst->ioapic.active_low = src->ioapic.active_low;
 887	} else {
 888		dst->ioapic.node = NUMA_NO_NODE;
 889		if (__acpi_get_override_irq(gsi, &level, &pol_low) >= 0) {
 890			dst->ioapic.is_level = level;
 891			dst->ioapic.active_low = pol_low;
 892		} else {
 893			/*
 894			 * PCI interrupts are always active low level
 895			 * triggered.
 896			 */
 897			dst->ioapic.is_level = true;
 898			dst->ioapic.active_low = true;
 899		}
 900	}
 901}
 902
 903static int ioapic_alloc_attr_node(struct irq_alloc_info *info)
 904{
 905	return (info && info->ioapic.valid) ? info->ioapic.node : NUMA_NO_NODE;
 906}
 907
 908static void mp_register_handler(unsigned int irq, bool level)
 909{
 910	irq_flow_handler_t hdl;
 911	bool fasteoi;
 912
 913	if (level) {
 914		irq_set_status_flags(irq, IRQ_LEVEL);
 915		fasteoi = true;
 916	} else {
 917		irq_clear_status_flags(irq, IRQ_LEVEL);
 918		fasteoi = false;
 919	}
 920
 921	hdl = fasteoi ? handle_fasteoi_irq : handle_edge_irq;
 922	__irq_set_handler(irq, hdl, 0, fasteoi ? "fasteoi" : "edge");
 923}
 924
 925static bool mp_check_pin_attr(int irq, struct irq_alloc_info *info)
 926{
 927	struct mp_chip_data *data = irq_get_chip_data(irq);
 928
 929	/*
 930	 * setup_IO_APIC_irqs() programs all legacy IRQs with default trigger
 931	 * and polarity attributes. So allow the first user to reprogram the
 932	 * pin with real trigger and polarity attributes.
 933	 */
 934	if (irq < nr_legacy_irqs() && data->count == 1) {
 935		if (info->ioapic.is_level != data->is_level)
 936			mp_register_handler(irq, info->ioapic.is_level);
 937		data->entry.is_level = data->is_level = info->ioapic.is_level;
 938		data->entry.active_low = data->active_low = info->ioapic.active_low;
 939	}
 940
 941	return data->is_level == info->ioapic.is_level &&
 942	       data->active_low == info->ioapic.active_low;
 943}
 944
 945static int alloc_irq_from_domain(struct irq_domain *domain, int ioapic, u32 gsi,
 946				 struct irq_alloc_info *info)
 947{
 948	bool legacy = false;
 949	int irq = -1;
 950	int type = ioapics[ioapic].irqdomain_cfg.type;
 951
 952	switch (type) {
 953	case IOAPIC_DOMAIN_LEGACY:
 954		/*
 955		 * Dynamically allocate IRQ number for non-ISA IRQs in the first
 956		 * 16 GSIs on some weird platforms.
 957		 */
 958		if (!ioapic_initialized || gsi >= nr_legacy_irqs())
 959			irq = gsi;
 960		legacy = mp_is_legacy_irq(irq);
 961		break;
 962	case IOAPIC_DOMAIN_STRICT:
 963		irq = gsi;
 964		break;
 965	case IOAPIC_DOMAIN_DYNAMIC:
 966		break;
 967	default:
 968		WARN(1, "ioapic: unknown irqdomain type %d\n", type);
 969		return -1;
 970	}
 971
 972	return __irq_domain_alloc_irqs(domain, irq, 1,
 973				       ioapic_alloc_attr_node(info),
 974				       info, legacy, NULL);
 975}
 976
 977/*
 978 * Need special handling for ISA IRQs because there may be multiple IOAPIC pins
 979 * sharing the same ISA IRQ number and irqdomain only supports 1:1 mapping
 980 * between IOAPIC pin and IRQ number. A typical IOAPIC has 24 pins, pin 0-15 are
 981 * used for legacy IRQs and pin 16-23 are used for PCI IRQs (PIRQ A-H).
 982 * When ACPI is disabled, only legacy IRQ numbers (IRQ0-15) are available, and
 983 * some BIOSes may use MP Interrupt Source records to override IRQ numbers for
 984 * PIRQs instead of reprogramming the interrupt routing logic. Thus there may be
 985 * multiple pins sharing the same legacy IRQ number when ACPI is disabled.
 986 */
 987static int alloc_isa_irq_from_domain(struct irq_domain *domain,
 988				     int irq, int ioapic, int pin,
 989				     struct irq_alloc_info *info)
 990{
 991	struct mp_chip_data *data;
 992	struct irq_data *irq_data = irq_get_irq_data(irq);
 993	int node = ioapic_alloc_attr_node(info);
 994
 995	/*
 996	 * Legacy ISA IRQ has already been allocated, just add pin to
 997	 * the pin list associated with this IRQ and program the IOAPIC
 998	 * entry. The IOAPIC entry
 999	 */
1000	if (irq_data && irq_data->parent_data) {
1001		if (!mp_check_pin_attr(irq, info))
1002			return -EBUSY;
1003		if (__add_pin_to_irq_node(irq_data->chip_data, node, ioapic,
1004					  info->ioapic.pin))
1005			return -ENOMEM;
1006	} else {
1007		info->flags |= X86_IRQ_ALLOC_LEGACY;
1008		irq = __irq_domain_alloc_irqs(domain, irq, 1, node, info, true,
1009					      NULL);
1010		if (irq >= 0) {
1011			irq_data = irq_domain_get_irq_data(domain, irq);
1012			data = irq_data->chip_data;
1013			data->isa_irq = true;
1014		}
1015	}
1016
1017	return irq;
1018}
1019
1020static int mp_map_pin_to_irq(u32 gsi, int idx, int ioapic, int pin,
1021			     unsigned int flags, struct irq_alloc_info *info)
1022{
1023	int irq;
1024	bool legacy = false;
1025	struct irq_alloc_info tmp;
1026	struct mp_chip_data *data;
1027	struct irq_domain *domain = mp_ioapic_irqdomain(ioapic);
1028
1029	if (!domain)
1030		return -ENOSYS;
1031
1032	if (idx >= 0 && test_bit(mp_irqs[idx].srcbus, mp_bus_not_pci)) {
1033		irq = mp_irqs[idx].srcbusirq;
1034		legacy = mp_is_legacy_irq(irq);
1035		/*
1036		 * IRQ2 is unusable for historical reasons on systems which
1037		 * have a legacy PIC. See the comment vs. IRQ2 further down.
1038		 *
1039		 * If this gets removed at some point then the related code
1040		 * in lapic_assign_system_vectors() needs to be adjusted as
1041		 * well.
1042		 */
1043		if (legacy && irq == PIC_CASCADE_IR)
1044			return -EINVAL;
1045	}
1046
1047	mutex_lock(&ioapic_mutex);
1048	if (!(flags & IOAPIC_MAP_ALLOC)) {
1049		if (!legacy) {
1050			irq = irq_find_mapping(domain, pin);
1051			if (irq == 0)
1052				irq = -ENOENT;
1053		}
1054	} else {
1055		ioapic_copy_alloc_attr(&tmp, info, gsi, ioapic, pin);
1056		if (legacy)
1057			irq = alloc_isa_irq_from_domain(domain, irq,
1058							ioapic, pin, &tmp);
1059		else if ((irq = irq_find_mapping(domain, pin)) == 0)
1060			irq = alloc_irq_from_domain(domain, ioapic, gsi, &tmp);
1061		else if (!mp_check_pin_attr(irq, &tmp))
1062			irq = -EBUSY;
1063		if (irq >= 0) {
1064			data = irq_get_chip_data(irq);
1065			data->count++;
1066		}
1067	}
1068	mutex_unlock(&ioapic_mutex);
1069
1070	return irq;
1071}
1072
1073static int pin_2_irq(int idx, int ioapic, int pin, unsigned int flags)
1074{
1075	u32 gsi = mp_pin_to_gsi(ioapic, pin);
1076
1077	/*
1078	 * Debugging check, we are in big trouble if this message pops up!
1079	 */
1080	if (mp_irqs[idx].dstirq != pin)
1081		pr_err("broken BIOS or MPTABLE parser, ayiee!!\n");
1082
1083#ifdef CONFIG_X86_32
1084	/*
1085	 * PCI IRQ command line redirection. Yes, limits are hardcoded.
1086	 */
1087	if ((pin >= 16) && (pin <= 23)) {
1088		if (pirq_entries[pin-16] != -1) {
1089			if (!pirq_entries[pin-16]) {
1090				apic_printk(APIC_VERBOSE, KERN_DEBUG
1091						"disabling PIRQ%d\n", pin-16);
1092			} else {
1093				int irq = pirq_entries[pin-16];
1094				apic_printk(APIC_VERBOSE, KERN_DEBUG
1095						"using PIRQ%d -> IRQ %d\n",
1096						pin-16, irq);
1097				return irq;
1098			}
1099		}
1100	}
1101#endif
1102
1103	return  mp_map_pin_to_irq(gsi, idx, ioapic, pin, flags, NULL);
1104}
1105
1106int mp_map_gsi_to_irq(u32 gsi, unsigned int flags, struct irq_alloc_info *info)
1107{
1108	int ioapic, pin, idx;
1109
1110	ioapic = mp_find_ioapic(gsi);
1111	if (ioapic < 0)
1112		return -ENODEV;
1113
1114	pin = mp_find_ioapic_pin(ioapic, gsi);
1115	idx = find_irq_entry(ioapic, pin, mp_INT);
1116	if ((flags & IOAPIC_MAP_CHECK) && idx < 0)
1117		return -ENODEV;
1118
1119	return mp_map_pin_to_irq(gsi, idx, ioapic, pin, flags, info);
1120}
1121
1122void mp_unmap_irq(int irq)
1123{
1124	struct irq_data *irq_data = irq_get_irq_data(irq);
1125	struct mp_chip_data *data;
1126
1127	if (!irq_data || !irq_data->domain)
1128		return;
1129
1130	data = irq_data->chip_data;
1131	if (!data || data->isa_irq)
1132		return;
1133
1134	mutex_lock(&ioapic_mutex);
1135	if (--data->count == 0)
1136		irq_domain_free_irqs(irq, 1);
1137	mutex_unlock(&ioapic_mutex);
1138}
1139
1140/*
1141 * Find a specific PCI IRQ entry.
1142 * Not an __init, possibly needed by modules
1143 */
1144int IO_APIC_get_PCI_irq_vector(int bus, int slot, int pin)
1145{
1146	int irq, i, best_ioapic = -1, best_idx = -1;
1147
1148	apic_printk(APIC_DEBUG,
1149		    "querying PCI -> IRQ mapping bus:%d, slot:%d, pin:%d.\n",
1150		    bus, slot, pin);
1151	if (test_bit(bus, mp_bus_not_pci)) {
1152		apic_printk(APIC_VERBOSE,
1153			    "PCI BIOS passed nonexistent PCI bus %d!\n", bus);
1154		return -1;
1155	}
1156
1157	for (i = 0; i < mp_irq_entries; i++) {
1158		int lbus = mp_irqs[i].srcbus;
1159		int ioapic_idx, found = 0;
1160
1161		if (bus != lbus || mp_irqs[i].irqtype != mp_INT ||
1162		    slot != ((mp_irqs[i].srcbusirq >> 2) & 0x1f))
1163			continue;
1164
1165		for_each_ioapic(ioapic_idx)
1166			if (mpc_ioapic_id(ioapic_idx) == mp_irqs[i].dstapic ||
1167			    mp_irqs[i].dstapic == MP_APIC_ALL) {
1168				found = 1;
1169				break;
1170			}
1171		if (!found)
1172			continue;
1173
1174		/* Skip ISA IRQs */
1175		irq = pin_2_irq(i, ioapic_idx, mp_irqs[i].dstirq, 0);
1176		if (irq > 0 && !IO_APIC_IRQ(irq))
1177			continue;
1178
1179		if (pin == (mp_irqs[i].srcbusirq & 3)) {
1180			best_idx = i;
1181			best_ioapic = ioapic_idx;
1182			goto out;
1183		}
1184
1185		/*
1186		 * Use the first all-but-pin matching entry as a
1187		 * best-guess fuzzy result for broken mptables.
1188		 */
1189		if (best_idx < 0) {
1190			best_idx = i;
1191			best_ioapic = ioapic_idx;
1192		}
1193	}
1194	if (best_idx < 0)
1195		return -1;
1196
1197out:
1198	return pin_2_irq(best_idx, best_ioapic, mp_irqs[best_idx].dstirq,
1199			 IOAPIC_MAP_ALLOC);
1200}
1201EXPORT_SYMBOL(IO_APIC_get_PCI_irq_vector);
1202
1203static struct irq_chip ioapic_chip, ioapic_ir_chip;
1204
1205static void __init setup_IO_APIC_irqs(void)
1206{
1207	unsigned int ioapic, pin;
1208	int idx;
1209
1210	apic_printk(APIC_VERBOSE, KERN_DEBUG "init IO_APIC IRQs\n");
1211
1212	for_each_ioapic_pin(ioapic, pin) {
1213		idx = find_irq_entry(ioapic, pin, mp_INT);
1214		if (idx < 0)
1215			apic_printk(APIC_VERBOSE,
1216				    KERN_DEBUG " apic %d pin %d not connected\n",
1217				    mpc_ioapic_id(ioapic), pin);
1218		else
1219			pin_2_irq(idx, ioapic, pin,
1220				  ioapic ? 0 : IOAPIC_MAP_ALLOC);
1221	}
1222}
1223
1224void ioapic_zap_locks(void)
1225{
1226	raw_spin_lock_init(&ioapic_lock);
1227}
1228
1229static void io_apic_print_entries(unsigned int apic, unsigned int nr_entries)
1230{
1231	struct IO_APIC_route_entry entry;
1232	char buf[256];
1233	int i;
1234
1235	printk(KERN_DEBUG "IOAPIC %d:\n", apic);
1236	for (i = 0; i <= nr_entries; i++) {
1237		entry = ioapic_read_entry(apic, i);
1238		snprintf(buf, sizeof(buf),
1239			 " pin%02x, %s, %s, %s, V(%02X), IRR(%1d), S(%1d)",
1240			 i,
1241			 entry.masked ? "disabled" : "enabled ",
1242			 entry.is_level ? "level" : "edge ",
1243			 entry.active_low ? "low " : "high",
1244			 entry.vector, entry.irr, entry.delivery_status);
1245		if (entry.ir_format) {
1246			printk(KERN_DEBUG "%s, remapped, I(%04X),  Z(%X)\n",
1247			       buf,
1248			       (entry.ir_index_15 << 15) | entry.ir_index_0_14,
1249				entry.ir_zero);
1250		} else {
1251			printk(KERN_DEBUG "%s, %s, D(%02X%02X), M(%1d)\n", buf,
1252			       entry.dest_mode_logical ? "logical " : "physical",
1253			       entry.virt_destid_8_14, entry.destid_0_7,
1254			       entry.delivery_mode);
1255		}
1256	}
1257}
1258
1259static void __init print_IO_APIC(int ioapic_idx)
1260{
1261	union IO_APIC_reg_00 reg_00;
1262	union IO_APIC_reg_01 reg_01;
1263	union IO_APIC_reg_02 reg_02;
1264	union IO_APIC_reg_03 reg_03;
1265	unsigned long flags;
1266
1267	raw_spin_lock_irqsave(&ioapic_lock, flags);
1268	reg_00.raw = io_apic_read(ioapic_idx, 0);
1269	reg_01.raw = io_apic_read(ioapic_idx, 1);
1270	if (reg_01.bits.version >= 0x10)
1271		reg_02.raw = io_apic_read(ioapic_idx, 2);
1272	if (reg_01.bits.version >= 0x20)
1273		reg_03.raw = io_apic_read(ioapic_idx, 3);
1274	raw_spin_unlock_irqrestore(&ioapic_lock, flags);
1275
1276	printk(KERN_DEBUG "IO APIC #%d......\n", mpc_ioapic_id(ioapic_idx));
1277	printk(KERN_DEBUG ".... register #00: %08X\n", reg_00.raw);
1278	printk(KERN_DEBUG ".......    : physical APIC id: %02X\n", reg_00.bits.ID);
1279	printk(KERN_DEBUG ".......    : Delivery Type: %X\n", reg_00.bits.delivery_type);
1280	printk(KERN_DEBUG ".......    : LTS          : %X\n", reg_00.bits.LTS);
1281
1282	printk(KERN_DEBUG ".... register #01: %08X\n", *(int *)&reg_01);
1283	printk(KERN_DEBUG ".......     : max redirection entries: %02X\n",
1284		reg_01.bits.entries);
1285
1286	printk(KERN_DEBUG ".......     : PRQ implemented: %X\n", reg_01.bits.PRQ);
1287	printk(KERN_DEBUG ".......     : IO APIC version: %02X\n",
1288		reg_01.bits.version);
1289
1290	/*
1291	 * Some Intel chipsets with IO APIC VERSION of 0x1? don't have reg_02,
1292	 * but the value of reg_02 is read as the previous read register
1293	 * value, so ignore it if reg_02 == reg_01.
1294	 */
1295	if (reg_01.bits.version >= 0x10 && reg_02.raw != reg_01.raw) {
1296		printk(KERN_DEBUG ".... register #02: %08X\n", reg_02.raw);
1297		printk(KERN_DEBUG ".......     : arbitration: %02X\n", reg_02.bits.arbitration);
1298	}
1299
1300	/*
1301	 * Some Intel chipsets with IO APIC VERSION of 0x2? don't have reg_02
1302	 * or reg_03, but the value of reg_0[23] is read as the previous read
1303	 * register value, so ignore it if reg_03 == reg_0[12].
1304	 */
1305	if (reg_01.bits.version >= 0x20 && reg_03.raw != reg_02.raw &&
1306	    reg_03.raw != reg_01.raw) {
1307		printk(KERN_DEBUG ".... register #03: %08X\n", reg_03.raw);
1308		printk(KERN_DEBUG ".......     : Boot DT    : %X\n", reg_03.bits.boot_DT);
1309	}
1310
1311	printk(KERN_DEBUG ".... IRQ redirection table:\n");
1312	io_apic_print_entries(ioapic_idx, reg_01.bits.entries);
1313}
1314
1315void __init print_IO_APICs(void)
1316{
1317	int ioapic_idx;
1318	unsigned int irq;
1319
1320	printk(KERN_DEBUG "number of MP IRQ sources: %d.\n", mp_irq_entries);
1321	for_each_ioapic(ioapic_idx)
1322		printk(KERN_DEBUG "number of IO-APIC #%d registers: %d.\n",
1323		       mpc_ioapic_id(ioapic_idx),
1324		       ioapics[ioapic_idx].nr_registers);
1325
1326	/*
1327	 * We are a bit conservative about what we expect.  We have to
1328	 * know about every hardware change ASAP.
1329	 */
1330	printk(KERN_INFO "testing the IO APIC.......................\n");
1331
1332	for_each_ioapic(ioapic_idx)
1333		print_IO_APIC(ioapic_idx);
1334
1335	printk(KERN_DEBUG "IRQ to pin mappings:\n");
1336	for_each_active_irq(irq) {
1337		struct irq_pin_list *entry;
1338		struct irq_chip *chip;
1339		struct mp_chip_data *data;
1340
1341		chip = irq_get_chip(irq);
1342		if (chip != &ioapic_chip && chip != &ioapic_ir_chip)
1343			continue;
1344		data = irq_get_chip_data(irq);
1345		if (!data)
1346			continue;
1347		if (list_empty(&data->irq_2_pin))
1348			continue;
1349
1350		printk(KERN_DEBUG "IRQ%d ", irq);
1351		for_each_irq_pin(entry, data->irq_2_pin)
1352			pr_cont("-> %d:%d", entry->apic, entry->pin);
1353		pr_cont("\n");
1354	}
1355
1356	printk(KERN_INFO ".................................... done.\n");
1357}
1358
1359/* Where if anywhere is the i8259 connect in external int mode */
1360static struct { int pin, apic; } ioapic_i8259 = { -1, -1 };
1361
1362void __init enable_IO_APIC(void)
1363{
1364	int i8259_apic, i8259_pin;
1365	int apic, pin;
1366
1367	if (skip_ioapic_setup)
1368		nr_ioapics = 0;
1369
1370	if (!nr_legacy_irqs() || !nr_ioapics)
1371		return;
1372
1373	for_each_ioapic_pin(apic, pin) {
1374		/* See if any of the pins is in ExtINT mode */
1375		struct IO_APIC_route_entry entry = ioapic_read_entry(apic, pin);
1376
1377		/* If the interrupt line is enabled and in ExtInt mode
1378		 * I have found the pin where the i8259 is connected.
1379		 */
1380		if (!entry.masked &&
1381		    entry.delivery_mode == APIC_DELIVERY_MODE_EXTINT) {
1382			ioapic_i8259.apic = apic;
1383			ioapic_i8259.pin  = pin;
1384			goto found_i8259;
1385		}
1386	}
1387 found_i8259:
1388	/* Look to see what if the MP table has reported the ExtINT */
1389	/* If we could not find the appropriate pin by looking at the ioapic
1390	 * the i8259 probably is not connected the ioapic but give the
1391	 * mptable a chance anyway.
1392	 */
1393	i8259_pin  = find_isa_irq_pin(0, mp_ExtINT);
1394	i8259_apic = find_isa_irq_apic(0, mp_ExtINT);
1395	/* Trust the MP table if nothing is setup in the hardware */
1396	if ((ioapic_i8259.pin == -1) && (i8259_pin >= 0)) {
1397		printk(KERN_WARNING "ExtINT not setup in hardware but reported by MP table\n");
1398		ioapic_i8259.pin  = i8259_pin;
1399		ioapic_i8259.apic = i8259_apic;
1400	}
1401	/* Complain if the MP table and the hardware disagree */
1402	if (((ioapic_i8259.apic != i8259_apic) || (ioapic_i8259.pin != i8259_pin)) &&
1403		(i8259_pin >= 0) && (ioapic_i8259.pin >= 0))
1404	{
1405		printk(KERN_WARNING "ExtINT in hardware and MP table differ\n");
1406	}
1407
1408	/*
1409	 * Do not trust the IO-APIC being empty at bootup
1410	 */
1411	clear_IO_APIC();
1412}
1413
1414void native_restore_boot_irq_mode(void)
1415{
1416	/*
1417	 * If the i8259 is routed through an IOAPIC
1418	 * Put that IOAPIC in virtual wire mode
1419	 * so legacy interrupts can be delivered.
1420	 */
1421	if (ioapic_i8259.pin != -1) {
1422		struct IO_APIC_route_entry entry;
1423		u32 apic_id = read_apic_id();
1424
1425		memset(&entry, 0, sizeof(entry));
1426		entry.masked		= false;
1427		entry.is_level		= false;
1428		entry.active_low	= false;
1429		entry.dest_mode_logical	= false;
1430		entry.delivery_mode	= APIC_DELIVERY_MODE_EXTINT;
1431		entry.destid_0_7	= apic_id & 0xFF;
1432		entry.virt_destid_8_14	= apic_id >> 8;
1433
1434		/*
1435		 * Add it to the IO-APIC irq-routing table:
1436		 */
1437		ioapic_write_entry(ioapic_i8259.apic, ioapic_i8259.pin, entry);
1438	}
1439
1440	if (boot_cpu_has(X86_FEATURE_APIC) || apic_from_smp_config())
1441		disconnect_bsp_APIC(ioapic_i8259.pin != -1);
1442}
1443
1444void restore_boot_irq_mode(void)
1445{
1446	if (!nr_legacy_irqs())
1447		return;
1448
1449	x86_apic_ops.restore();
1450}
1451
1452#ifdef CONFIG_X86_32
1453/*
1454 * function to set the IO-APIC physical IDs based on the
1455 * values stored in the MPC table.
1456 *
1457 * by Matt Domsch <Matt_Domsch@dell.com>  Tue Dec 21 12:25:05 CST 1999
1458 */
1459void __init setup_ioapic_ids_from_mpc_nocheck(void)
1460{
1461	union IO_APIC_reg_00 reg_00;
1462	physid_mask_t phys_id_present_map;
1463	int ioapic_idx;
1464	int i;
1465	unsigned char old_id;
1466	unsigned long flags;
1467
1468	/*
1469	 * This is broken; anything with a real cpu count has to
1470	 * circumvent this idiocy regardless.
1471	 */
1472	apic->ioapic_phys_id_map(&phys_cpu_present_map, &phys_id_present_map);
1473
1474	/*
1475	 * Set the IOAPIC ID to the value stored in the MPC table.
1476	 */
1477	for_each_ioapic(ioapic_idx) {
1478		/* Read the register 0 value */
1479		raw_spin_lock_irqsave(&ioapic_lock, flags);
1480		reg_00.raw = io_apic_read(ioapic_idx, 0);
1481		raw_spin_unlock_irqrestore(&ioapic_lock, flags);
1482
1483		old_id = mpc_ioapic_id(ioapic_idx);
1484
1485		if (mpc_ioapic_id(ioapic_idx) >= get_physical_broadcast()) {
1486			printk(KERN_ERR "BIOS bug, IO-APIC#%d ID is %d in the MPC table!...\n",
1487				ioapic_idx, mpc_ioapic_id(ioapic_idx));
1488			printk(KERN_ERR "... fixing up to %d. (tell your hw vendor)\n",
1489				reg_00.bits.ID);
1490			ioapics[ioapic_idx].mp_config.apicid = reg_00.bits.ID;
1491		}
1492
1493		/*
1494		 * Sanity check, is the ID really free? Every APIC in a
1495		 * system must have a unique ID or we get lots of nice
1496		 * 'stuck on smp_invalidate_needed IPI wait' messages.
1497		 */
1498		if (apic->check_apicid_used(&phys_id_present_map,
1499					    mpc_ioapic_id(ioapic_idx))) {
1500			printk(KERN_ERR "BIOS bug, IO-APIC#%d ID %d is already used!...\n",
1501				ioapic_idx, mpc_ioapic_id(ioapic_idx));
1502			for (i = 0; i < get_physical_broadcast(); i++)
1503				if (!physid_isset(i, phys_id_present_map))
1504					break;
1505			if (i >= get_physical_broadcast())
1506				panic("Max APIC ID exceeded!\n");
1507			printk(KERN_ERR "... fixing up to %d. (tell your hw vendor)\n",
1508				i);
1509			physid_set(i, phys_id_present_map);
1510			ioapics[ioapic_idx].mp_config.apicid = i;
1511		} else {
1512			physid_mask_t tmp;
1513			apic->apicid_to_cpu_present(mpc_ioapic_id(ioapic_idx),
1514						    &tmp);
1515			apic_printk(APIC_VERBOSE, "Setting %d in the "
1516					"phys_id_present_map\n",
1517					mpc_ioapic_id(ioapic_idx));
1518			physids_or(phys_id_present_map, phys_id_present_map, tmp);
1519		}
1520
1521		/*
1522		 * We need to adjust the IRQ routing table
1523		 * if the ID changed.
1524		 */
1525		if (old_id != mpc_ioapic_id(ioapic_idx))
1526			for (i = 0; i < mp_irq_entries; i++)
1527				if (mp_irqs[i].dstapic == old_id)
1528					mp_irqs[i].dstapic
1529						= mpc_ioapic_id(ioapic_idx);
1530
1531		/*
1532		 * Update the ID register according to the right value
1533		 * from the MPC table if they are different.
1534		 */
1535		if (mpc_ioapic_id(ioapic_idx) == reg_00.bits.ID)
1536			continue;
1537
1538		apic_printk(APIC_VERBOSE, KERN_INFO
1539			"...changing IO-APIC physical APIC ID to %d ...",
1540			mpc_ioapic_id(ioapic_idx));
1541
1542		reg_00.bits.ID = mpc_ioapic_id(ioapic_idx);
1543		raw_spin_lock_irqsave(&ioapic_lock, flags);
1544		io_apic_write(ioapic_idx, 0, reg_00.raw);
1545		raw_spin_unlock_irqrestore(&ioapic_lock, flags);
1546
1547		/*
1548		 * Sanity check
1549		 */
1550		raw_spin_lock_irqsave(&ioapic_lock, flags);
1551		reg_00.raw = io_apic_read(ioapic_idx, 0);
1552		raw_spin_unlock_irqrestore(&ioapic_lock, flags);
1553		if (reg_00.bits.ID != mpc_ioapic_id(ioapic_idx))
1554			pr_cont("could not set ID!\n");
1555		else
1556			apic_printk(APIC_VERBOSE, " ok.\n");
1557	}
1558}
1559
1560void __init setup_ioapic_ids_from_mpc(void)
1561{
1562
1563	if (acpi_ioapic)
1564		return;
1565	/*
1566	 * Don't check I/O APIC IDs for xAPIC systems.  They have
1567	 * no meaning without the serial APIC bus.
1568	 */
1569	if (!(boot_cpu_data.x86_vendor == X86_VENDOR_INTEL)
1570		|| APIC_XAPIC(boot_cpu_apic_version))
1571		return;
1572	setup_ioapic_ids_from_mpc_nocheck();
1573}
1574#endif
1575
1576int no_timer_check __initdata;
1577
1578static int __init notimercheck(char *s)
1579{
1580	no_timer_check = 1;
1581	return 1;
1582}
1583__setup("no_timer_check", notimercheck);
1584
1585static void __init delay_with_tsc(void)
1586{
1587	unsigned long long start, now;
1588	unsigned long end = jiffies + 4;
1589
1590	start = rdtsc();
1591
1592	/*
1593	 * We don't know the TSC frequency yet, but waiting for
1594	 * 40000000000/HZ TSC cycles is safe:
1595	 * 4 GHz == 10 jiffies
1596	 * 1 GHz == 40 jiffies
1597	 */
1598	do {
1599		rep_nop();
1600		now = rdtsc();
1601	} while ((now - start) < 40000000000ULL / HZ &&
1602		time_before_eq(jiffies, end));
1603}
1604
1605static void __init delay_without_tsc(void)
1606{
1607	unsigned long end = jiffies + 4;
1608	int band = 1;
1609
1610	/*
1611	 * We don't know any frequency yet, but waiting for
1612	 * 40940000000/HZ cycles is safe:
1613	 * 4 GHz == 10 jiffies
1614	 * 1 GHz == 40 jiffies
1615	 * 1 << 1 + 1 << 2 +...+ 1 << 11 = 4094
1616	 */
1617	do {
1618		__delay(((1U << band++) * 10000000UL) / HZ);
1619	} while (band < 12 && time_before_eq(jiffies, end));
1620}
1621
1622/*
1623 * There is a nasty bug in some older SMP boards, their mptable lies
1624 * about the timer IRQ. We do the following to work around the situation:
1625 *
1626 *	- timer IRQ defaults to IO-APIC IRQ
1627 *	- if this function detects that timer IRQs are defunct, then we fall
1628 *	  back to ISA timer IRQs
1629 */
1630static int __init timer_irq_works(void)
1631{
1632	unsigned long t1 = jiffies;
1633
1634	if (no_timer_check)
1635		return 1;
1636
1637	local_irq_enable();
1638	if (boot_cpu_has(X86_FEATURE_TSC))
1639		delay_with_tsc();
1640	else
1641		delay_without_tsc();
1642
1643	/*
1644	 * Expect a few ticks at least, to be sure some possible
1645	 * glue logic does not lock up after one or two first
1646	 * ticks in a non-ExtINT mode.  Also the local APIC
1647	 * might have cached one ExtINT interrupt.  Finally, at
1648	 * least one tick may be lost due to delays.
1649	 */
1650
1651	local_irq_disable();
1652
1653	/* Did jiffies advance? */
1654	return time_after(jiffies, t1 + 4);
1655}
1656
1657/*
1658 * In the SMP+IOAPIC case it might happen that there are an unspecified
1659 * number of pending IRQ events unhandled. These cases are very rare,
1660 * so we 'resend' these IRQs via IPIs, to the same CPU. It's much
1661 * better to do it this way as thus we do not have to be aware of
1662 * 'pending' interrupts in the IRQ path, except at this point.
1663 */
1664/*
1665 * Edge triggered needs to resend any interrupt
1666 * that was delayed but this is now handled in the device
1667 * independent code.
1668 */
1669
1670/*
1671 * Starting up a edge-triggered IO-APIC interrupt is
1672 * nasty - we need to make sure that we get the edge.
1673 * If it is already asserted for some reason, we need
1674 * return 1 to indicate that is was pending.
1675 *
1676 * This is not complete - we should be able to fake
1677 * an edge even if it isn't on the 8259A...
1678 */
1679static unsigned int startup_ioapic_irq(struct irq_data *data)
1680{
1681	int was_pending = 0, irq = data->irq;
1682	unsigned long flags;
1683
1684	raw_spin_lock_irqsave(&ioapic_lock, flags);
1685	if (irq < nr_legacy_irqs()) {
1686		legacy_pic->mask(irq);
1687		if (legacy_pic->irq_pending(irq))
1688			was_pending = 1;
1689	}
1690	__unmask_ioapic(data->chip_data);
1691	raw_spin_unlock_irqrestore(&ioapic_lock, flags);
1692
1693	return was_pending;
1694}
1695
1696atomic_t irq_mis_count;
1697
1698#ifdef CONFIG_GENERIC_PENDING_IRQ
1699static bool io_apic_level_ack_pending(struct mp_chip_data *data)
1700{
1701	struct irq_pin_list *entry;
1702	unsigned long flags;
1703
1704	raw_spin_lock_irqsave(&ioapic_lock, flags);
1705	for_each_irq_pin(entry, data->irq_2_pin) {
1706		struct IO_APIC_route_entry e;
1707		int pin;
1708
1709		pin = entry->pin;
1710		e.w1 = io_apic_read(entry->apic, 0x10 + pin*2);
1711		/* Is the remote IRR bit set? */
1712		if (e.irr) {
1713			raw_spin_unlock_irqrestore(&ioapic_lock, flags);
1714			return true;
1715		}
1716	}
1717	raw_spin_unlock_irqrestore(&ioapic_lock, flags);
1718
1719	return false;
1720}
1721
1722static inline bool ioapic_prepare_move(struct irq_data *data)
1723{
1724	/* If we are moving the IRQ we need to mask it */
1725	if (unlikely(irqd_is_setaffinity_pending(data))) {
1726		if (!irqd_irq_masked(data))
1727			mask_ioapic_irq(data);
1728		return true;
1729	}
1730	return false;
1731}
1732
1733static inline void ioapic_finish_move(struct irq_data *data, bool moveit)
1734{
1735	if (unlikely(moveit)) {
1736		/* Only migrate the irq if the ack has been received.
1737		 *
1738		 * On rare occasions the broadcast level triggered ack gets
1739		 * delayed going to ioapics, and if we reprogram the
1740		 * vector while Remote IRR is still set the irq will never
1741		 * fire again.
1742		 *
1743		 * To prevent this scenario we read the Remote IRR bit
1744		 * of the ioapic.  This has two effects.
1745		 * - On any sane system the read of the ioapic will
1746		 *   flush writes (and acks) going to the ioapic from
1747		 *   this cpu.
1748		 * - We get to see if the ACK has actually been delivered.
1749		 *
1750		 * Based on failed experiments of reprogramming the
1751		 * ioapic entry from outside of irq context starting
1752		 * with masking the ioapic entry and then polling until
1753		 * Remote IRR was clear before reprogramming the
1754		 * ioapic I don't trust the Remote IRR bit to be
1755		 * completely accurate.
1756		 *
1757		 * However there appears to be no other way to plug
1758		 * this race, so if the Remote IRR bit is not
1759		 * accurate and is causing problems then it is a hardware bug
1760		 * and you can go talk to the chipset vendor about it.
1761		 */
1762		if (!io_apic_level_ack_pending(data->chip_data))
1763			irq_move_masked_irq(data);
1764		/* If the IRQ is masked in the core, leave it: */
1765		if (!irqd_irq_masked(data))
1766			unmask_ioapic_irq(data);
1767	}
1768}
1769#else
1770static inline bool ioapic_prepare_move(struct irq_data *data)
1771{
1772	return false;
1773}
1774static inline void ioapic_finish_move(struct irq_data *data, bool moveit)
1775{
1776}
1777#endif
1778
1779static void ioapic_ack_level(struct irq_data *irq_data)
1780{
1781	struct irq_cfg *cfg = irqd_cfg(irq_data);
1782	unsigned long v;
1783	bool moveit;
1784	int i;
1785
1786	irq_complete_move(cfg);
1787	moveit = ioapic_prepare_move(irq_data);
1788
1789	/*
1790	 * It appears there is an erratum which affects at least version 0x11
1791	 * of I/O APIC (that's the 82093AA and cores integrated into various
1792	 * chipsets).  Under certain conditions a level-triggered interrupt is
1793	 * erroneously delivered as edge-triggered one but the respective IRR
1794	 * bit gets set nevertheless.  As a result the I/O unit expects an EOI
1795	 * message but it will never arrive and further interrupts are blocked
1796	 * from the source.  The exact reason is so far unknown, but the
1797	 * phenomenon was observed when two consecutive interrupt requests
1798	 * from a given source get delivered to the same CPU and the source is
1799	 * temporarily disabled in between.
1800	 *
1801	 * A workaround is to simulate an EOI message manually.  We achieve it
1802	 * by setting the trigger mode to edge and then to level when the edge
1803	 * trigger mode gets detected in the TMR of a local APIC for a
1804	 * level-triggered interrupt.  We mask the source for the time of the
1805	 * operation to prevent an edge-triggered interrupt escaping meanwhile.
1806	 * The idea is from Manfred Spraul.  --macro
1807	 *
1808	 * Also in the case when cpu goes offline, fixup_irqs() will forward
1809	 * any unhandled interrupt on the offlined cpu to the new cpu
1810	 * destination that is handling the corresponding interrupt. This
1811	 * interrupt forwarding is done via IPI's. Hence, in this case also
1812	 * level-triggered io-apic interrupt will be seen as an edge
1813	 * interrupt in the IRR. And we can't rely on the cpu's EOI
1814	 * to be broadcasted to the IO-APIC's which will clear the remoteIRR
1815	 * corresponding to the level-triggered interrupt. Hence on IO-APIC's
1816	 * supporting EOI register, we do an explicit EOI to clear the
1817	 * remote IRR and on IO-APIC's which don't have an EOI register,
1818	 * we use the above logic (mask+edge followed by unmask+level) from
1819	 * Manfred Spraul to clear the remote IRR.
1820	 */
1821	i = cfg->vector;
1822	v = apic_read(APIC_TMR + ((i & ~0x1f) >> 1));
1823
1824	/*
1825	 * We must acknowledge the irq before we move it or the acknowledge will
1826	 * not propagate properly.
1827	 */
1828	ack_APIC_irq();
1829
1830	/*
1831	 * Tail end of clearing remote IRR bit (either by delivering the EOI
1832	 * message via io-apic EOI register write or simulating it using
1833	 * mask+edge followed by unmask+level logic) manually when the
1834	 * level triggered interrupt is seen as the edge triggered interrupt
1835	 * at the cpu.
1836	 */
1837	if (!(v & (1 << (i & 0x1f)))) {
1838		atomic_inc(&irq_mis_count);
1839		eoi_ioapic_pin(cfg->vector, irq_data->chip_data);
1840	}
1841
1842	ioapic_finish_move(irq_data, moveit);
1843}
1844
1845static void ioapic_ir_ack_level(struct irq_data *irq_data)
1846{
1847	struct mp_chip_data *data = irq_data->chip_data;
1848
1849	/*
1850	 * Intr-remapping uses pin number as the virtual vector
1851	 * in the RTE. Actual vector is programmed in
1852	 * intr-remapping table entry. Hence for the io-apic
1853	 * EOI we use the pin number.
1854	 */
1855	apic_ack_irq(irq_data);
1856	eoi_ioapic_pin(data->entry.vector, data);
1857}
1858
1859/*
1860 * The I/OAPIC is just a device for generating MSI messages from legacy
1861 * interrupt pins. Various fields of the RTE translate into bits of the
1862 * resulting MSI which had a historical meaning.
1863 *
1864 * With interrupt remapping, many of those bits have different meanings
1865 * in the underlying MSI, but the way that the I/OAPIC transforms them
1866 * from its RTE to the MSI message is the same. This function allows
1867 * the parent IRQ domain to compose the MSI message, then takes the
1868 * relevant bits to put them in the appropriate places in the RTE in
1869 * order to generate that message when the IRQ happens.
1870 *
1871 * The setup here relies on a preconfigured route entry (is_level,
1872 * active_low, masked) because the parent domain is merely composing the
1873 * generic message routing information which is used for the MSI.
1874 */
1875static void ioapic_setup_msg_from_msi(struct irq_data *irq_data,
1876				      struct IO_APIC_route_entry *entry)
1877{
1878	struct msi_msg msg;
1879
1880	/* Let the parent domain compose the MSI message */
1881	irq_chip_compose_msi_msg(irq_data, &msg);
1882
1883	/*
1884	 * - Real vector
1885	 * - DMAR/IR: 8bit subhandle (ioapic.pin)
1886	 * - AMD/IR:  8bit IRTE index
1887	 */
1888	entry->vector			= msg.arch_data.vector;
1889	/* Delivery mode (for DMAR/IR all 0) */
1890	entry->delivery_mode		= msg.arch_data.delivery_mode;
1891	/* Destination mode or DMAR/IR index bit 15 */
1892	entry->dest_mode_logical	= msg.arch_addr_lo.dest_mode_logical;
1893	/* DMAR/IR: 1, 0 for all other modes */
1894	entry->ir_format		= msg.arch_addr_lo.dmar_format;
1895	/*
1896	 * - DMAR/IR: index bit 0-14.
1897	 *
1898	 * - Virt: If the host supports x2apic without a virtualized IR
1899	 *	   unit then bit 0-6 of dmar_index_0_14 are providing bit
1900	 *	   8-14 of the destination id.
1901	 *
1902	 * All other modes have bit 0-6 of dmar_index_0_14 cleared and the
1903	 * topmost 8 bits are destination id bit 0-7 (entry::destid_0_7).
1904	 */
1905	entry->ir_index_0_14		= msg.arch_addr_lo.dmar_index_0_14;
1906}
1907
1908static void ioapic_configure_entry(struct irq_data *irqd)
1909{
1910	struct mp_chip_data *mpd = irqd->chip_data;
1911	struct irq_pin_list *entry;
1912
1913	ioapic_setup_msg_from_msi(irqd, &mpd->entry);
1914
1915	for_each_irq_pin(entry, mpd->irq_2_pin)
1916		__ioapic_write_entry(entry->apic, entry->pin, mpd->entry);
1917}
1918
1919static int ioapic_set_affinity(struct irq_data *irq_data,
1920			       const struct cpumask *mask, bool force)
1921{
1922	struct irq_data *parent = irq_data->parent_data;
1923	unsigned long flags;
1924	int ret;
1925
1926	ret = parent->chip->irq_set_affinity(parent, mask, force);
1927	raw_spin_lock_irqsave(&ioapic_lock, flags);
1928	if (ret >= 0 && ret != IRQ_SET_MASK_OK_DONE)
1929		ioapic_configure_entry(irq_data);
1930	raw_spin_unlock_irqrestore(&ioapic_lock, flags);
1931
1932	return ret;
1933}
1934
1935/*
1936 * Interrupt shutdown masks the ioapic pin, but the interrupt might already
1937 * be in flight, but not yet serviced by the target CPU. That means
1938 * __synchronize_hardirq() would return and claim that everything is calmed
1939 * down. So free_irq() would proceed and deactivate the interrupt and free
1940 * resources.
1941 *
1942 * Once the target CPU comes around to service it it will find a cleared
1943 * vector and complain. While the spurious interrupt is harmless, the full
1944 * release of resources might prevent the interrupt from being acknowledged
1945 * which keeps the hardware in a weird state.
1946 *
1947 * Verify that the corresponding Remote-IRR bits are clear.
1948 */
1949static int ioapic_irq_get_chip_state(struct irq_data *irqd,
1950				   enum irqchip_irq_state which,
1951				   bool *state)
1952{
1953	struct mp_chip_data *mcd = irqd->chip_data;
1954	struct IO_APIC_route_entry rentry;
1955	struct irq_pin_list *p;
1956
1957	if (which != IRQCHIP_STATE_ACTIVE)
1958		return -EINVAL;
1959
1960	*state = false;
1961	raw_spin_lock(&ioapic_lock);
1962	for_each_irq_pin(p, mcd->irq_2_pin) {
1963		rentry = __ioapic_read_entry(p->apic, p->pin);
1964		/*
1965		 * The remote IRR is only valid in level trigger mode. It's
1966		 * meaning is undefined for edge triggered interrupts and
1967		 * irrelevant because the IO-APIC treats them as fire and
1968		 * forget.
1969		 */
1970		if (rentry.irr && rentry.is_level) {
1971			*state = true;
1972			break;
1973		}
1974	}
1975	raw_spin_unlock(&ioapic_lock);
1976	return 0;
1977}
1978
1979static struct irq_chip ioapic_chip __read_mostly = {
1980	.name			= "IO-APIC",
1981	.irq_startup		= startup_ioapic_irq,
1982	.irq_mask		= mask_ioapic_irq,
1983	.irq_unmask		= unmask_ioapic_irq,
1984	.irq_ack		= irq_chip_ack_parent,
1985	.irq_eoi		= ioapic_ack_level,
1986	.irq_set_affinity	= ioapic_set_affinity,
1987	.irq_retrigger		= irq_chip_retrigger_hierarchy,
1988	.irq_get_irqchip_state	= ioapic_irq_get_chip_state,
1989	.flags			= IRQCHIP_SKIP_SET_WAKE |
1990				  IRQCHIP_AFFINITY_PRE_STARTUP,
1991};
1992
1993static struct irq_chip ioapic_ir_chip __read_mostly = {
1994	.name			= "IR-IO-APIC",
1995	.irq_startup		= startup_ioapic_irq,
1996	.irq_mask		= mask_ioapic_irq,
1997	.irq_unmask		= unmask_ioapic_irq,
1998	.irq_ack		= irq_chip_ack_parent,
1999	.irq_eoi		= ioapic_ir_ack_level,
2000	.irq_set_affinity	= ioapic_set_affinity,
2001	.irq_retrigger		= irq_chip_retrigger_hierarchy,
2002	.irq_get_irqchip_state	= ioapic_irq_get_chip_state,
2003	.flags			= IRQCHIP_SKIP_SET_WAKE |
2004				  IRQCHIP_AFFINITY_PRE_STARTUP,
2005};
2006
2007static inline void init_IO_APIC_traps(void)
2008{
2009	struct irq_cfg *cfg;
2010	unsigned int irq;
2011
2012	for_each_active_irq(irq) {
2013		cfg = irq_cfg(irq);
2014		if (IO_APIC_IRQ(irq) && cfg && !cfg->vector) {
2015			/*
2016			 * Hmm.. We don't have an entry for this,
2017			 * so default to an old-fashioned 8259
2018			 * interrupt if we can..
2019			 */
2020			if (irq < nr_legacy_irqs())
2021				legacy_pic->make_irq(irq);
2022			else
2023				/* Strange. Oh, well.. */
2024				irq_set_chip(irq, &no_irq_chip);
2025		}
2026	}
2027}
2028
2029/*
2030 * The local APIC irq-chip implementation:
2031 */
2032
2033static void mask_lapic_irq(struct irq_data *data)
2034{
2035	unsigned long v;
2036
2037	v = apic_read(APIC_LVT0);
2038	apic_write(APIC_LVT0, v | APIC_LVT_MASKED);
2039}
2040
2041static void unmask_lapic_irq(struct irq_data *data)
2042{
2043	unsigned long v;
2044
2045	v = apic_read(APIC_LVT0);
2046	apic_write(APIC_LVT0, v & ~APIC_LVT_MASKED);
2047}
2048
2049static void ack_lapic_irq(struct irq_data *data)
2050{
2051	ack_APIC_irq();
2052}
2053
2054static struct irq_chip lapic_chip __read_mostly = {
2055	.name		= "local-APIC",
2056	.irq_mask	= mask_lapic_irq,
2057	.irq_unmask	= unmask_lapic_irq,
2058	.irq_ack	= ack_lapic_irq,
2059};
2060
2061static void lapic_register_intr(int irq)
2062{
2063	irq_clear_status_flags(irq, IRQ_LEVEL);
2064	irq_set_chip_and_handler_name(irq, &lapic_chip, handle_edge_irq,
2065				      "edge");
2066}
2067
2068/*
2069 * This looks a bit hackish but it's about the only one way of sending
2070 * a few INTA cycles to 8259As and any associated glue logic.  ICR does
2071 * not support the ExtINT mode, unfortunately.  We need to send these
2072 * cycles as some i82489DX-based boards have glue logic that keeps the
2073 * 8259A interrupt line asserted until INTA.  --macro
2074 */
2075static inline void __init unlock_ExtINT_logic(void)
2076{
2077	int apic, pin, i;
2078	struct IO_APIC_route_entry entry0, entry1;
2079	unsigned char save_control, save_freq_select;
2080	u32 apic_id;
2081
2082	pin  = find_isa_irq_pin(8, mp_INT);
2083	if (pin == -1) {
2084		WARN_ON_ONCE(1);
2085		return;
2086	}
2087	apic = find_isa_irq_apic(8, mp_INT);
2088	if (apic == -1) {
2089		WARN_ON_ONCE(1);
2090		return;
2091	}
2092
2093	entry0 = ioapic_read_entry(apic, pin);
2094	clear_IO_APIC_pin(apic, pin);
2095
2096	apic_id = hard_smp_processor_id();
2097	memset(&entry1, 0, sizeof(entry1));
2098
2099	entry1.dest_mode_logical	= true;
2100	entry1.masked			= false;
2101	entry1.destid_0_7		= apic_id & 0xFF;
2102	entry1.virt_destid_8_14		= apic_id >> 8;
2103	entry1.delivery_mode		= APIC_DELIVERY_MODE_EXTINT;
2104	entry1.active_low		= entry0.active_low;
2105	entry1.is_level			= false;
2106	entry1.vector = 0;
2107
2108	ioapic_write_entry(apic, pin, entry1);
2109
2110	save_control = CMOS_READ(RTC_CONTROL);
2111	save_freq_select = CMOS_READ(RTC_FREQ_SELECT);
2112	CMOS_WRITE((save_freq_select & ~RTC_RATE_SELECT) | 0x6,
2113		   RTC_FREQ_SELECT);
2114	CMOS_WRITE(save_control | RTC_PIE, RTC_CONTROL);
2115
2116	i = 100;
2117	while (i-- > 0) {
2118		mdelay(10);
2119		if ((CMOS_READ(RTC_INTR_FLAGS) & RTC_PF) == RTC_PF)
2120			i -= 10;
2121	}
2122
2123	CMOS_WRITE(save_control, RTC_CONTROL);
2124	CMOS_WRITE(save_freq_select, RTC_FREQ_SELECT);
2125	clear_IO_APIC_pin(apic, pin);
2126
2127	ioapic_write_entry(apic, pin, entry0);
2128}
2129
2130static int disable_timer_pin_1 __initdata;
2131/* Actually the next is obsolete, but keep it for paranoid reasons -AK */
2132static int __init disable_timer_pin_setup(char *arg)
2133{
2134	disable_timer_pin_1 = 1;
2135	return 0;
2136}
2137early_param("disable_timer_pin_1", disable_timer_pin_setup);
2138
2139static int mp_alloc_timer_irq(int ioapic, int pin)
2140{
2141	int irq = -1;
2142	struct irq_domain *domain = mp_ioapic_irqdomain(ioapic);
2143
2144	if (domain) {
2145		struct irq_alloc_info info;
2146
2147		ioapic_set_alloc_attr(&info, NUMA_NO_NODE, 0, 0);
2148		info.devid = mpc_ioapic_id(ioapic);
2149		info.ioapic.pin = pin;
2150		mutex_lock(&ioapic_mutex);
2151		irq = alloc_isa_irq_from_domain(domain, 0, ioapic, pin, &info);
2152		mutex_unlock(&ioapic_mutex);
2153	}
2154
2155	return irq;
2156}
2157
2158/*
2159 * This code may look a bit paranoid, but it's supposed to cooperate with
2160 * a wide range of boards and BIOS bugs.  Fortunately only the timer IRQ
2161 * is so screwy.  Thanks to Brian Perkins for testing/hacking this beast
2162 * fanatically on his truly buggy board.
2163 *
2164 * FIXME: really need to revamp this for all platforms.
2165 */
2166static inline void __init check_timer(void)
2167{
2168	struct irq_data *irq_data = irq_get_irq_data(0);
2169	struct mp_chip_data *data = irq_data->chip_data;
2170	struct irq_cfg *cfg = irqd_cfg(irq_data);
2171	int node = cpu_to_node(0);
2172	int apic1, pin1, apic2, pin2;
2173	int no_pin1 = 0;
2174
2175	if (!global_clock_event)
2176		return;
2177
2178	local_irq_disable();
2179
2180	/*
2181	 * get/set the timer IRQ vector:
2182	 */
2183	legacy_pic->mask(0);
2184
2185	/*
2186	 * As IRQ0 is to be enabled in the 8259A, the virtual
2187	 * wire has to be disabled in the local APIC.  Also
2188	 * timer interrupts need to be acknowledged manually in
2189	 * the 8259A for the i82489DX when using the NMI
2190	 * watchdog as that APIC treats NMIs as level-triggered.
2191	 * The AEOI mode will finish them in the 8259A
2192	 * automatically.
2193	 */
2194	apic_write(APIC_LVT0, APIC_LVT_MASKED | APIC_DM_EXTINT);
2195	legacy_pic->init(1);
2196
2197	pin1  = find_isa_irq_pin(0, mp_INT);
2198	apic1 = find_isa_irq_apic(0, mp_INT);
2199	pin2  = ioapic_i8259.pin;
2200	apic2 = ioapic_i8259.apic;
2201
2202	apic_printk(APIC_QUIET, KERN_INFO "..TIMER: vector=0x%02X "
2203		    "apic1=%d pin1=%d apic2=%d pin2=%d\n",
2204		    cfg->vector, apic1, pin1, apic2, pin2);
2205
2206	/*
2207	 * Some BIOS writers are clueless and report the ExtINTA
2208	 * I/O APIC input from the cascaded 8259A as the timer
2209	 * interrupt input.  So just in case, if only one pin
2210	 * was found above, try it both directly and through the
2211	 * 8259A.
2212	 */
2213	if (pin1 == -1) {
2214		panic_if_irq_remap("BIOS bug: timer not connected to IO-APIC");
2215		pin1 = pin2;
2216		apic1 = apic2;
2217		no_pin1 = 1;
2218	} else if (pin2 == -1) {
2219		pin2 = pin1;
2220		apic2 = apic1;
2221	}
2222
2223	if (pin1 != -1) {
2224		/* Ok, does IRQ0 through the IOAPIC work? */
2225		if (no_pin1) {
2226			mp_alloc_timer_irq(apic1, pin1);
2227		} else {
2228			/*
2229			 * for edge trigger, it's already unmasked,
2230			 * so only need to unmask if it is level-trigger
2231			 * do we really have level trigger timer?
2232			 */
2233			int idx = find_irq_entry(apic1, pin1, mp_INT);
2234
2235			if (idx != -1 && irq_is_level(idx))
2236				unmask_ioapic_irq(irq_get_irq_data(0));
2237		}
2238		irq_domain_deactivate_irq(irq_data);
2239		irq_domain_activate_irq(irq_data, false);
2240		if (timer_irq_works()) {
2241			if (disable_timer_pin_1 > 0)
2242				clear_IO_APIC_pin(0, pin1);
2243			goto out;
2244		}
2245		panic_if_irq_remap("timer doesn't work through Interrupt-remapped IO-APIC");
2246		clear_IO_APIC_pin(apic1, pin1);
2247		if (!no_pin1)
2248			apic_printk(APIC_QUIET, KERN_ERR "..MP-BIOS bug: "
2249				    "8254 timer not connected to IO-APIC\n");
2250
2251		apic_printk(APIC_QUIET, KERN_INFO "...trying to set up timer "
2252			    "(IRQ0) through the 8259A ...\n");
2253		apic_printk(APIC_QUIET, KERN_INFO
2254			    "..... (found apic %d pin %d) ...\n", apic2, pin2);
2255		/*
2256		 * legacy devices should be connected to IO APIC #0
2257		 */
2258		replace_pin_at_irq_node(data, node, apic1, pin1, apic2, pin2);
2259		irq_domain_deactivate_irq(irq_data);
2260		irq_domain_activate_irq(irq_data, false);
2261		legacy_pic->unmask(0);
2262		if (timer_irq_works()) {
2263			apic_printk(APIC_QUIET, KERN_INFO "....... works.\n");
2264			goto out;
2265		}
2266		/*
2267		 * Cleanup, just in case ...
2268		 */
2269		legacy_pic->mask(0);
2270		clear_IO_APIC_pin(apic2, pin2);
2271		apic_printk(APIC_QUIET, KERN_INFO "....... failed.\n");
2272	}
2273
2274	apic_printk(APIC_QUIET, KERN_INFO
2275		    "...trying to set up timer as Virtual Wire IRQ...\n");
2276
2277	lapic_register_intr(0);
2278	apic_write(APIC_LVT0, APIC_DM_FIXED | cfg->vector);	/* Fixed mode */
2279	legacy_pic->unmask(0);
2280
2281	if (timer_irq_works()) {
2282		apic_printk(APIC_QUIET, KERN_INFO "..... works.\n");
2283		goto out;
2284	}
2285	legacy_pic->mask(0);
2286	apic_write(APIC_LVT0, APIC_LVT_MASKED | APIC_DM_FIXED | cfg->vector);
2287	apic_printk(APIC_QUIET, KERN_INFO "..... failed.\n");
2288
2289	apic_printk(APIC_QUIET, KERN_INFO
2290		    "...trying to set up timer as ExtINT IRQ...\n");
2291
2292	legacy_pic->init(0);
2293	legacy_pic->make_irq(0);
2294	apic_write(APIC_LVT0, APIC_DM_EXTINT);
2295	legacy_pic->unmask(0);
2296
2297	unlock_ExtINT_logic();
2298
2299	if (timer_irq_works()) {
2300		apic_printk(APIC_QUIET, KERN_INFO "..... works.\n");
2301		goto out;
2302	}
2303	apic_printk(APIC_QUIET, KERN_INFO "..... failed :(.\n");
2304	if (apic_is_x2apic_enabled())
2305		apic_printk(APIC_QUIET, KERN_INFO
2306			    "Perhaps problem with the pre-enabled x2apic mode\n"
2307			    "Try booting with x2apic and interrupt-remapping disabled in the bios.\n");
2308	panic("IO-APIC + timer doesn't work!  Boot with apic=debug and send a "
2309		"report.  Then try booting with the 'noapic' option.\n");
2310out:
2311	local_irq_enable();
2312}
2313
2314/*
2315 * Traditionally ISA IRQ2 is the cascade IRQ, and is not available
2316 * to devices.  However there may be an I/O APIC pin available for
2317 * this interrupt regardless.  The pin may be left unconnected, but
2318 * typically it will be reused as an ExtINT cascade interrupt for
2319 * the master 8259A.  In the MPS case such a pin will normally be
2320 * reported as an ExtINT interrupt in the MP table.  With ACPI
2321 * there is no provision for ExtINT interrupts, and in the absence
2322 * of an override it would be treated as an ordinary ISA I/O APIC
2323 * interrupt, that is edge-triggered and unmasked by default.  We
2324 * used to do this, but it caused problems on some systems because
2325 * of the NMI watchdog and sometimes IRQ0 of the 8254 timer using
2326 * the same ExtINT cascade interrupt to drive the local APIC of the
2327 * bootstrap processor.  Therefore we refrain from routing IRQ2 to
2328 * the I/O APIC in all cases now.  No actual device should request
2329 * it anyway.  --macro
2330 */
2331#define PIC_IRQS	(1UL << PIC_CASCADE_IR)
2332
2333static int mp_irqdomain_create(int ioapic)
2334{
2335	struct irq_domain *parent;
2336	int hwirqs = mp_ioapic_pin_count(ioapic);
2337	struct ioapic *ip = &ioapics[ioapic];
2338	struct ioapic_domain_cfg *cfg = &ip->irqdomain_cfg;
2339	struct mp_ioapic_gsi *gsi_cfg = mp_ioapic_gsi_routing(ioapic);
2340	struct fwnode_handle *fn;
2341	struct irq_fwspec fwspec;
2342
2343	if (cfg->type == IOAPIC_DOMAIN_INVALID)
2344		return 0;
2345
2346	/* Handle device tree enumerated APICs proper */
2347	if (cfg->dev) {
2348		fn = of_node_to_fwnode(cfg->dev);
2349	} else {
2350		fn = irq_domain_alloc_named_id_fwnode("IO-APIC", mpc_ioapic_id(ioapic));
2351		if (!fn)
2352			return -ENOMEM;
2353	}
2354
2355	fwspec.fwnode = fn;
2356	fwspec.param_count = 1;
2357	fwspec.param[0] = mpc_ioapic_id(ioapic);
2358
2359	parent = irq_find_matching_fwspec(&fwspec, DOMAIN_BUS_ANY);
2360	if (!parent) {
2361		if (!cfg->dev)
2362			irq_domain_free_fwnode(fn);
2363		return -ENODEV;
2364	}
2365
2366	ip->irqdomain = irq_domain_create_linear(fn, hwirqs, cfg->ops,
2367						 (void *)(long)ioapic);
2368
2369	if (!ip->irqdomain) {
2370		/* Release fw handle if it was allocated above */
2371		if (!cfg->dev)
2372			irq_domain_free_fwnode(fn);
2373		return -ENOMEM;
2374	}
2375
2376	ip->irqdomain->parent = parent;
2377
2378	if (cfg->type == IOAPIC_DOMAIN_LEGACY ||
2379	    cfg->type == IOAPIC_DOMAIN_STRICT)
2380		ioapic_dynirq_base = max(ioapic_dynirq_base,
2381					 gsi_cfg->gsi_end + 1);
2382
2383	return 0;
2384}
2385
2386static void ioapic_destroy_irqdomain(int idx)
2387{
2388	struct ioapic_domain_cfg *cfg = &ioapics[idx].irqdomain_cfg;
2389	struct fwnode_handle *fn = ioapics[idx].irqdomain->fwnode;
2390
2391	if (ioapics[idx].irqdomain) {
2392		irq_domain_remove(ioapics[idx].irqdomain);
2393		if (!cfg->dev)
2394			irq_domain_free_fwnode(fn);
2395		ioapics[idx].irqdomain = NULL;
2396	}
2397}
2398
2399void __init setup_IO_APIC(void)
2400{
2401	int ioapic;
2402
2403	if (skip_ioapic_setup || !nr_ioapics)
2404		return;
2405
2406	io_apic_irqs = nr_legacy_irqs() ? ~PIC_IRQS : ~0UL;
2407
2408	apic_printk(APIC_VERBOSE, "ENABLING IO-APIC IRQs\n");
2409	for_each_ioapic(ioapic)
2410		BUG_ON(mp_irqdomain_create(ioapic));
2411
2412	/*
2413         * Set up IO-APIC IRQ routing.
2414         */
2415	x86_init.mpparse.setup_ioapic_ids();
2416
2417	sync_Arb_IDs();
2418	setup_IO_APIC_irqs();
2419	init_IO_APIC_traps();
2420	if (nr_legacy_irqs())
2421		check_timer();
2422
2423	ioapic_initialized = 1;
2424}
2425
2426static void resume_ioapic_id(int ioapic_idx)
2427{
2428	unsigned long flags;
2429	union IO_APIC_reg_00 reg_00;
2430
2431	raw_spin_lock_irqsave(&ioapic_lock, flags);
2432	reg_00.raw = io_apic_read(ioapic_idx, 0);
2433	if (reg_00.bits.ID != mpc_ioapic_id(ioapic_idx)) {
2434		reg_00.bits.ID = mpc_ioapic_id(ioapic_idx);
2435		io_apic_write(ioapic_idx, 0, reg_00.raw);
2436	}
2437	raw_spin_unlock_irqrestore(&ioapic_lock, flags);
2438}
2439
2440static void ioapic_resume(void)
2441{
2442	int ioapic_idx;
2443
2444	for_each_ioapic_reverse(ioapic_idx)
2445		resume_ioapic_id(ioapic_idx);
2446
2447	restore_ioapic_entries();
2448}
2449
2450static struct syscore_ops ioapic_syscore_ops = {
2451	.suspend = save_ioapic_entries,
2452	.resume = ioapic_resume,
2453};
2454
2455static int __init ioapic_init_ops(void)
2456{
2457	register_syscore_ops(&ioapic_syscore_ops);
2458
2459	return 0;
2460}
2461
2462device_initcall(ioapic_init_ops);
2463
2464static int io_apic_get_redir_entries(int ioapic)
2465{
2466	union IO_APIC_reg_01	reg_01;
2467	unsigned long flags;
2468
2469	raw_spin_lock_irqsave(&ioapic_lock, flags);
2470	reg_01.raw = io_apic_read(ioapic, 1);
2471	raw_spin_unlock_irqrestore(&ioapic_lock, flags);
2472
2473	/* The register returns the maximum index redir index
2474	 * supported, which is one less than the total number of redir
2475	 * entries.
2476	 */
2477	return reg_01.bits.entries + 1;
2478}
2479
2480unsigned int arch_dynirq_lower_bound(unsigned int from)
2481{
 
 
2482	/*
2483	 * dmar_alloc_hwirq() may be called before setup_IO_APIC(), so use
2484	 * gsi_top if ioapic_dynirq_base hasn't been initialized yet.
2485	 */
2486	if (!ioapic_initialized)
2487		return gsi_top;
2488	/*
2489	 * For DT enabled machines ioapic_dynirq_base is irrelevant and not
2490	 * updated. So simply return @from if ioapic_dynirq_base == 0.
 
 
2491	 */
2492	return ioapic_dynirq_base ? : from;
2493}
2494
2495#ifdef CONFIG_X86_32
2496static int io_apic_get_unique_id(int ioapic, int apic_id)
2497{
2498	union IO_APIC_reg_00 reg_00;
2499	static physid_mask_t apic_id_map = PHYSID_MASK_NONE;
2500	physid_mask_t tmp;
2501	unsigned long flags;
2502	int i = 0;
2503
2504	/*
2505	 * The P4 platform supports up to 256 APIC IDs on two separate APIC
2506	 * buses (one for LAPICs, one for IOAPICs), where predecessors only
2507	 * supports up to 16 on one shared APIC bus.
2508	 *
2509	 * TBD: Expand LAPIC/IOAPIC support on P4-class systems to take full
2510	 *      advantage of new APIC bus architecture.
2511	 */
2512
2513	if (physids_empty(apic_id_map))
2514		apic->ioapic_phys_id_map(&phys_cpu_present_map, &apic_id_map);
2515
2516	raw_spin_lock_irqsave(&ioapic_lock, flags);
2517	reg_00.raw = io_apic_read(ioapic, 0);
2518	raw_spin_unlock_irqrestore(&ioapic_lock, flags);
2519
2520	if (apic_id >= get_physical_broadcast()) {
2521		printk(KERN_WARNING "IOAPIC[%d]: Invalid apic_id %d, trying "
2522			"%d\n", ioapic, apic_id, reg_00.bits.ID);
2523		apic_id = reg_00.bits.ID;
2524	}
2525
2526	/*
2527	 * Every APIC in a system must have a unique ID or we get lots of nice
2528	 * 'stuck on smp_invalidate_needed IPI wait' messages.
2529	 */
2530	if (apic->check_apicid_used(&apic_id_map, apic_id)) {
2531
2532		for (i = 0; i < get_physical_broadcast(); i++) {
2533			if (!apic->check_apicid_used(&apic_id_map, i))
2534				break;
2535		}
2536
2537		if (i == get_physical_broadcast())
2538			panic("Max apic_id exceeded!\n");
2539
2540		printk(KERN_WARNING "IOAPIC[%d]: apic_id %d already used, "
2541			"trying %d\n", ioapic, apic_id, i);
2542
2543		apic_id = i;
2544	}
2545
2546	apic->apicid_to_cpu_present(apic_id, &tmp);
2547	physids_or(apic_id_map, apic_id_map, tmp);
2548
2549	if (reg_00.bits.ID != apic_id) {
2550		reg_00.bits.ID = apic_id;
2551
2552		raw_spin_lock_irqsave(&ioapic_lock, flags);
2553		io_apic_write(ioapic, 0, reg_00.raw);
2554		reg_00.raw = io_apic_read(ioapic, 0);
2555		raw_spin_unlock_irqrestore(&ioapic_lock, flags);
2556
2557		/* Sanity check */
2558		if (reg_00.bits.ID != apic_id) {
2559			pr_err("IOAPIC[%d]: Unable to change apic_id!\n",
2560			       ioapic);
2561			return -1;
2562		}
2563	}
2564
2565	apic_printk(APIC_VERBOSE, KERN_INFO
2566			"IOAPIC[%d]: Assigned apic_id %d\n", ioapic, apic_id);
2567
2568	return apic_id;
2569}
2570
2571static u8 io_apic_unique_id(int idx, u8 id)
2572{
2573	if ((boot_cpu_data.x86_vendor == X86_VENDOR_INTEL) &&
2574	    !APIC_XAPIC(boot_cpu_apic_version))
2575		return io_apic_get_unique_id(idx, id);
2576	else
2577		return id;
2578}
2579#else
2580static u8 io_apic_unique_id(int idx, u8 id)
2581{
2582	union IO_APIC_reg_00 reg_00;
2583	DECLARE_BITMAP(used, 256);
2584	unsigned long flags;
2585	u8 new_id;
2586	int i;
2587
2588	bitmap_zero(used, 256);
2589	for_each_ioapic(i)
2590		__set_bit(mpc_ioapic_id(i), used);
2591
2592	/* Hand out the requested id if available */
2593	if (!test_bit(id, used))
2594		return id;
2595
2596	/*
2597	 * Read the current id from the ioapic and keep it if
2598	 * available.
2599	 */
2600	raw_spin_lock_irqsave(&ioapic_lock, flags);
2601	reg_00.raw = io_apic_read(idx, 0);
2602	raw_spin_unlock_irqrestore(&ioapic_lock, flags);
2603	new_id = reg_00.bits.ID;
2604	if (!test_bit(new_id, used)) {
2605		apic_printk(APIC_VERBOSE, KERN_INFO
2606			"IOAPIC[%d]: Using reg apic_id %d instead of %d\n",
2607			 idx, new_id, id);
2608		return new_id;
2609	}
2610
2611	/*
2612	 * Get the next free id and write it to the ioapic.
2613	 */
2614	new_id = find_first_zero_bit(used, 256);
2615	reg_00.bits.ID = new_id;
2616	raw_spin_lock_irqsave(&ioapic_lock, flags);
2617	io_apic_write(idx, 0, reg_00.raw);
2618	reg_00.raw = io_apic_read(idx, 0);
2619	raw_spin_unlock_irqrestore(&ioapic_lock, flags);
2620	/* Sanity check */
2621	BUG_ON(reg_00.bits.ID != new_id);
2622
2623	return new_id;
2624}
2625#endif
2626
2627static int io_apic_get_version(int ioapic)
2628{
2629	union IO_APIC_reg_01	reg_01;
2630	unsigned long flags;
2631
2632	raw_spin_lock_irqsave(&ioapic_lock, flags);
2633	reg_01.raw = io_apic_read(ioapic, 1);
2634	raw_spin_unlock_irqrestore(&ioapic_lock, flags);
2635
2636	return reg_01.bits.version;
2637}
2638
2639/*
2640 * This function updates target affinity of IOAPIC interrupts to include
2641 * the CPUs which came online during SMP bringup.
2642 */
2643#define IOAPIC_RESOURCE_NAME_SIZE 11
2644
2645static struct resource *ioapic_resources;
2646
2647static struct resource * __init ioapic_setup_resources(void)
2648{
2649	unsigned long n;
2650	struct resource *res;
2651	char *mem;
2652	int i;
2653
2654	if (nr_ioapics == 0)
2655		return NULL;
2656
2657	n = IOAPIC_RESOURCE_NAME_SIZE + sizeof(struct resource);
2658	n *= nr_ioapics;
2659
2660	mem = memblock_alloc(n, SMP_CACHE_BYTES);
2661	if (!mem)
2662		panic("%s: Failed to allocate %lu bytes\n", __func__, n);
2663	res = (void *)mem;
2664
2665	mem += sizeof(struct resource) * nr_ioapics;
2666
2667	for_each_ioapic(i) {
2668		res[i].name = mem;
2669		res[i].flags = IORESOURCE_MEM | IORESOURCE_BUSY;
2670		snprintf(mem, IOAPIC_RESOURCE_NAME_SIZE, "IOAPIC %u", i);
2671		mem += IOAPIC_RESOURCE_NAME_SIZE;
2672		ioapics[i].iomem_res = &res[i];
2673	}
2674
2675	ioapic_resources = res;
2676
2677	return res;
2678}
2679
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2680void __init io_apic_init_mappings(void)
2681{
2682	unsigned long ioapic_phys, idx = FIX_IO_APIC_BASE_0;
2683	struct resource *ioapic_res;
2684	int i;
2685
2686	ioapic_res = ioapic_setup_resources();
2687	for_each_ioapic(i) {
2688		if (smp_found_config) {
2689			ioapic_phys = mpc_ioapic_addr(i);
2690#ifdef CONFIG_X86_32
2691			if (!ioapic_phys) {
2692				printk(KERN_ERR
2693				       "WARNING: bogus zero IO-APIC "
2694				       "address found in MPTABLE, "
2695				       "disabling IO/APIC support!\n");
2696				smp_found_config = 0;
2697				skip_ioapic_setup = 1;
2698				goto fake_ioapic_page;
2699			}
2700#endif
2701		} else {
2702#ifdef CONFIG_X86_32
2703fake_ioapic_page:
2704#endif
2705			ioapic_phys = (unsigned long)memblock_alloc(PAGE_SIZE,
2706								    PAGE_SIZE);
2707			if (!ioapic_phys)
2708				panic("%s: Failed to allocate %lu bytes align=0x%lx\n",
2709				      __func__, PAGE_SIZE, PAGE_SIZE);
2710			ioapic_phys = __pa(ioapic_phys);
2711		}
2712		set_fixmap_nocache(idx, ioapic_phys);
2713		apic_printk(APIC_VERBOSE, "mapped IOAPIC to %08lx (%08lx)\n",
2714			__fix_to_virt(idx) + (ioapic_phys & ~PAGE_MASK),
2715			ioapic_phys);
2716		idx++;
2717
2718		ioapic_res->start = ioapic_phys;
2719		ioapic_res->end = ioapic_phys + IO_APIC_SLOT_SIZE - 1;
2720		ioapic_res++;
2721	}
2722}
2723
2724void __init ioapic_insert_resources(void)
2725{
2726	int i;
2727	struct resource *r = ioapic_resources;
2728
2729	if (!r) {
2730		if (nr_ioapics > 0)
2731			printk(KERN_ERR
2732				"IO APIC resources couldn't be allocated.\n");
2733		return;
2734	}
2735
2736	for_each_ioapic(i) {
2737		insert_resource(&iomem_resource, r);
2738		r++;
2739	}
2740}
2741
2742int mp_find_ioapic(u32 gsi)
2743{
2744	int i;
2745
2746	if (nr_ioapics == 0)
2747		return -1;
2748
2749	/* Find the IOAPIC that manages this GSI. */
2750	for_each_ioapic(i) {
2751		struct mp_ioapic_gsi *gsi_cfg = mp_ioapic_gsi_routing(i);
2752		if (gsi >= gsi_cfg->gsi_base && gsi <= gsi_cfg->gsi_end)
2753			return i;
2754	}
2755
2756	printk(KERN_ERR "ERROR: Unable to locate IOAPIC for GSI %d\n", gsi);
2757	return -1;
2758}
2759
2760int mp_find_ioapic_pin(int ioapic, u32 gsi)
2761{
2762	struct mp_ioapic_gsi *gsi_cfg;
2763
2764	if (WARN_ON(ioapic < 0))
2765		return -1;
2766
2767	gsi_cfg = mp_ioapic_gsi_routing(ioapic);
2768	if (WARN_ON(gsi > gsi_cfg->gsi_end))
2769		return -1;
2770
2771	return gsi - gsi_cfg->gsi_base;
2772}
2773
2774static int bad_ioapic_register(int idx)
2775{
2776	union IO_APIC_reg_00 reg_00;
2777	union IO_APIC_reg_01 reg_01;
2778	union IO_APIC_reg_02 reg_02;
2779
2780	reg_00.raw = io_apic_read(idx, 0);
2781	reg_01.raw = io_apic_read(idx, 1);
2782	reg_02.raw = io_apic_read(idx, 2);
2783
2784	if (reg_00.raw == -1 && reg_01.raw == -1 && reg_02.raw == -1) {
2785		pr_warn("I/O APIC 0x%x registers return all ones, skipping!\n",
2786			mpc_ioapic_addr(idx));
2787		return 1;
2788	}
2789
2790	return 0;
2791}
2792
2793static int find_free_ioapic_entry(void)
2794{
2795	int idx;
2796
2797	for (idx = 0; idx < MAX_IO_APICS; idx++)
2798		if (ioapics[idx].nr_registers == 0)
2799			return idx;
2800
2801	return MAX_IO_APICS;
2802}
2803
2804/**
2805 * mp_register_ioapic - Register an IOAPIC device
2806 * @id:		hardware IOAPIC ID
2807 * @address:	physical address of IOAPIC register area
2808 * @gsi_base:	base of GSI associated with the IOAPIC
2809 * @cfg:	configuration information for the IOAPIC
2810 */
2811int mp_register_ioapic(int id, u32 address, u32 gsi_base,
2812		       struct ioapic_domain_cfg *cfg)
2813{
2814	bool hotplug = !!ioapic_initialized;
2815	struct mp_ioapic_gsi *gsi_cfg;
2816	int idx, ioapic, entries;
2817	u32 gsi_end;
2818
2819	if (!address) {
2820		pr_warn("Bogus (zero) I/O APIC address found, skipping!\n");
2821		return -EINVAL;
2822	}
2823	for_each_ioapic(ioapic)
2824		if (ioapics[ioapic].mp_config.apicaddr == address) {
2825			pr_warn("address 0x%x conflicts with IOAPIC%d\n",
2826				address, ioapic);
2827			return -EEXIST;
2828		}
2829
2830	idx = find_free_ioapic_entry();
2831	if (idx >= MAX_IO_APICS) {
2832		pr_warn("Max # of I/O APICs (%d) exceeded (found %d), skipping\n",
2833			MAX_IO_APICS, idx);
2834		return -ENOSPC;
2835	}
2836
2837	ioapics[idx].mp_config.type = MP_IOAPIC;
2838	ioapics[idx].mp_config.flags = MPC_APIC_USABLE;
2839	ioapics[idx].mp_config.apicaddr = address;
2840
2841	set_fixmap_nocache(FIX_IO_APIC_BASE_0 + idx, address);
2842	if (bad_ioapic_register(idx)) {
2843		clear_fixmap(FIX_IO_APIC_BASE_0 + idx);
2844		return -ENODEV;
2845	}
2846
2847	ioapics[idx].mp_config.apicid = io_apic_unique_id(idx, id);
2848	ioapics[idx].mp_config.apicver = io_apic_get_version(idx);
2849
2850	/*
2851	 * Build basic GSI lookup table to facilitate gsi->io_apic lookups
2852	 * and to prevent reprogramming of IOAPIC pins (PCI GSIs).
2853	 */
2854	entries = io_apic_get_redir_entries(idx);
2855	gsi_end = gsi_base + entries - 1;
2856	for_each_ioapic(ioapic) {
2857		gsi_cfg = mp_ioapic_gsi_routing(ioapic);
2858		if ((gsi_base >= gsi_cfg->gsi_base &&
2859		     gsi_base <= gsi_cfg->gsi_end) ||
2860		    (gsi_end >= gsi_cfg->gsi_base &&
2861		     gsi_end <= gsi_cfg->gsi_end)) {
2862			pr_warn("GSI range [%u-%u] for new IOAPIC conflicts with GSI[%u-%u]\n",
2863				gsi_base, gsi_end,
2864				gsi_cfg->gsi_base, gsi_cfg->gsi_end);
2865			clear_fixmap(FIX_IO_APIC_BASE_0 + idx);
2866			return -ENOSPC;
2867		}
2868	}
2869	gsi_cfg = mp_ioapic_gsi_routing(idx);
2870	gsi_cfg->gsi_base = gsi_base;
2871	gsi_cfg->gsi_end = gsi_end;
2872
2873	ioapics[idx].irqdomain = NULL;
2874	ioapics[idx].irqdomain_cfg = *cfg;
2875
2876	/*
2877	 * If mp_register_ioapic() is called during early boot stage when
2878	 * walking ACPI/DT tables, it's too early to create irqdomain,
2879	 * we are still using bootmem allocator. So delay it to setup_IO_APIC().
2880	 */
2881	if (hotplug) {
2882		if (mp_irqdomain_create(idx)) {
2883			clear_fixmap(FIX_IO_APIC_BASE_0 + idx);
2884			return -ENOMEM;
2885		}
2886		alloc_ioapic_saved_registers(idx);
2887	}
2888
2889	if (gsi_cfg->gsi_end >= gsi_top)
2890		gsi_top = gsi_cfg->gsi_end + 1;
2891	if (nr_ioapics <= idx)
2892		nr_ioapics = idx + 1;
2893
2894	/* Set nr_registers to mark entry present */
2895	ioapics[idx].nr_registers = entries;
2896
2897	pr_info("IOAPIC[%d]: apic_id %d, version %d, address 0x%x, GSI %d-%d\n",
2898		idx, mpc_ioapic_id(idx),
2899		mpc_ioapic_ver(idx), mpc_ioapic_addr(idx),
2900		gsi_cfg->gsi_base, gsi_cfg->gsi_end);
2901
2902	return 0;
2903}
2904
2905int mp_unregister_ioapic(u32 gsi_base)
2906{
2907	int ioapic, pin;
2908	int found = 0;
2909
2910	for_each_ioapic(ioapic)
2911		if (ioapics[ioapic].gsi_config.gsi_base == gsi_base) {
2912			found = 1;
2913			break;
2914		}
2915	if (!found) {
2916		pr_warn("can't find IOAPIC for GSI %d\n", gsi_base);
2917		return -ENODEV;
2918	}
2919
2920	for_each_pin(ioapic, pin) {
2921		u32 gsi = mp_pin_to_gsi(ioapic, pin);
2922		int irq = mp_map_gsi_to_irq(gsi, 0, NULL);
2923		struct mp_chip_data *data;
2924
2925		if (irq >= 0) {
2926			data = irq_get_chip_data(irq);
2927			if (data && data->count) {
2928				pr_warn("pin%d on IOAPIC%d is still in use.\n",
2929					pin, ioapic);
2930				return -EBUSY;
2931			}
2932		}
2933	}
2934
2935	/* Mark entry not present */
2936	ioapics[ioapic].nr_registers  = 0;
2937	ioapic_destroy_irqdomain(ioapic);
2938	free_ioapic_saved_registers(ioapic);
2939	if (ioapics[ioapic].iomem_res)
2940		release_resource(ioapics[ioapic].iomem_res);
2941	clear_fixmap(FIX_IO_APIC_BASE_0 + ioapic);
2942	memset(&ioapics[ioapic], 0, sizeof(ioapics[ioapic]));
2943
2944	return 0;
2945}
2946
2947int mp_ioapic_registered(u32 gsi_base)
2948{
2949	int ioapic;
2950
2951	for_each_ioapic(ioapic)
2952		if (ioapics[ioapic].gsi_config.gsi_base == gsi_base)
2953			return 1;
2954
2955	return 0;
2956}
2957
2958static void mp_irqdomain_get_attr(u32 gsi, struct mp_chip_data *data,
2959				  struct irq_alloc_info *info)
2960{
2961	if (info && info->ioapic.valid) {
2962		data->is_level = info->ioapic.is_level;
2963		data->active_low = info->ioapic.active_low;
2964	} else if (__acpi_get_override_irq(gsi, &data->is_level,
2965					   &data->active_low) < 0) {
2966		/* PCI interrupts are always active low level triggered. */
2967		data->is_level = true;
2968		data->active_low = true;
2969	}
2970}
2971
2972/*
2973 * Configure the I/O-APIC specific fields in the routing entry.
2974 *
2975 * This is important to setup the I/O-APIC specific bits (is_level,
2976 * active_low, masked) because the underlying parent domain will only
2977 * provide the routing information and is oblivious of the I/O-APIC
2978 * specific bits.
2979 *
2980 * The entry is just preconfigured at this point and not written into the
2981 * RTE. This happens later during activation which will fill in the actual
2982 * routing information.
2983 */
2984static void mp_preconfigure_entry(struct mp_chip_data *data)
2985{
2986	struct IO_APIC_route_entry *entry = &data->entry;
2987
2988	memset(entry, 0, sizeof(*entry));
2989	entry->is_level		 = data->is_level;
2990	entry->active_low	 = data->active_low;
2991	/*
2992	 * Mask level triggered irqs. Edge triggered irqs are masked
2993	 * by the irq core code in case they fire.
2994	 */
2995	entry->masked		= data->is_level;
2996}
2997
2998int mp_irqdomain_alloc(struct irq_domain *domain, unsigned int virq,
2999		       unsigned int nr_irqs, void *arg)
3000{
3001	struct irq_alloc_info *info = arg;
3002	struct mp_chip_data *data;
3003	struct irq_data *irq_data;
3004	int ret, ioapic, pin;
3005	unsigned long flags;
3006
3007	if (!info || nr_irqs > 1)
3008		return -EINVAL;
3009	irq_data = irq_domain_get_irq_data(domain, virq);
3010	if (!irq_data)
3011		return -EINVAL;
3012
3013	ioapic = mp_irqdomain_ioapic_idx(domain);
3014	pin = info->ioapic.pin;
3015	if (irq_find_mapping(domain, (irq_hw_number_t)pin) > 0)
3016		return -EEXIST;
3017
3018	data = kzalloc(sizeof(*data), GFP_KERNEL);
3019	if (!data)
3020		return -ENOMEM;
3021
3022	ret = irq_domain_alloc_irqs_parent(domain, virq, nr_irqs, info);
3023	if (ret < 0) {
3024		kfree(data);
3025		return ret;
3026	}
3027
3028	INIT_LIST_HEAD(&data->irq_2_pin);
3029	irq_data->hwirq = info->ioapic.pin;
3030	irq_data->chip = (domain->parent == x86_vector_domain) ?
3031			  &ioapic_chip : &ioapic_ir_chip;
3032	irq_data->chip_data = data;
3033	mp_irqdomain_get_attr(mp_pin_to_gsi(ioapic, pin), data, info);
3034
3035	add_pin_to_irq_node(data, ioapic_alloc_attr_node(info), ioapic, pin);
3036
3037	mp_preconfigure_entry(data);
3038	mp_register_handler(virq, data->is_level);
3039
3040	local_irq_save(flags);
3041	if (virq < nr_legacy_irqs())
3042		legacy_pic->mask(virq);
3043	local_irq_restore(flags);
3044
3045	apic_printk(APIC_VERBOSE, KERN_DEBUG
3046		    "IOAPIC[%d]: Preconfigured routing entry (%d-%d -> IRQ %d Level:%i ActiveLow:%i)\n",
3047		    ioapic, mpc_ioapic_id(ioapic), pin, virq,
3048		    data->is_level, data->active_low);
3049	return 0;
3050}
3051
3052void mp_irqdomain_free(struct irq_domain *domain, unsigned int virq,
3053		       unsigned int nr_irqs)
3054{
3055	struct irq_data *irq_data;
3056	struct mp_chip_data *data;
3057
3058	BUG_ON(nr_irqs != 1);
3059	irq_data = irq_domain_get_irq_data(domain, virq);
3060	if (irq_data && irq_data->chip_data) {
3061		data = irq_data->chip_data;
3062		__remove_pin_from_irq(data, mp_irqdomain_ioapic_idx(domain),
3063				      (int)irq_data->hwirq);
3064		WARN_ON(!list_empty(&data->irq_2_pin));
3065		kfree(irq_data->chip_data);
3066	}
3067	irq_domain_free_irqs_top(domain, virq, nr_irqs);
3068}
3069
3070int mp_irqdomain_activate(struct irq_domain *domain,
3071			  struct irq_data *irq_data, bool reserve)
3072{
3073	unsigned long flags;
3074
3075	raw_spin_lock_irqsave(&ioapic_lock, flags);
3076	ioapic_configure_entry(irq_data);
3077	raw_spin_unlock_irqrestore(&ioapic_lock, flags);
3078	return 0;
3079}
3080
3081void mp_irqdomain_deactivate(struct irq_domain *domain,
3082			     struct irq_data *irq_data)
3083{
3084	/* It won't be called for IRQ with multiple IOAPIC pins associated */
3085	ioapic_mask_entry(mp_irqdomain_ioapic_idx(domain),
3086			  (int)irq_data->hwirq);
3087}
3088
3089int mp_irqdomain_ioapic_idx(struct irq_domain *domain)
3090{
3091	return (int)(long)domain->host_data;
3092}
3093
3094const struct irq_domain_ops mp_ioapic_irqdomain_ops = {
3095	.alloc		= mp_irqdomain_alloc,
3096	.free		= mp_irqdomain_free,
3097	.activate	= mp_irqdomain_activate,
3098	.deactivate	= mp_irqdomain_deactivate,
3099};