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