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v6.13.7
   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	/* # of IRQ routing registers */
 109	int				nr_registers;
 110	/* Saved state during suspend/resume, or while enabling intr-remap. */
 111	struct IO_APIC_route_entry	*saved_registers;
 
 
 
 
 112	/* I/O APIC config */
 113	struct mpc_ioapic		mp_config;
 114	/* IO APIC gsi routing info */
 115	struct mp_ioapic_gsi		gsi_config;
 116	struct ioapic_domain_cfg	irqdomain_cfg;
 117	struct irq_domain		*irqdomain;
 118	struct resource			*iomem_res;
 119} ioapics[MAX_IO_APICS];
 120
 121#define mpc_ioapic_ver(ioapic_idx)	ioapics[ioapic_idx].mp_config.apicver
 122
 123int mpc_ioapic_id(int ioapic_idx)
 124{
 125	return ioapics[ioapic_idx].mp_config.apicid;
 126}
 127
 128unsigned int mpc_ioapic_addr(int ioapic_idx)
 129{
 130	return ioapics[ioapic_idx].mp_config.apicaddr;
 131}
 132
 133static inline struct mp_ioapic_gsi *mp_ioapic_gsi_routing(int ioapic_idx)
 134{
 135	return &ioapics[ioapic_idx].gsi_config;
 136}
 137
 138static inline int mp_ioapic_pin_count(int ioapic)
 139{
 140	struct mp_ioapic_gsi *gsi_cfg = mp_ioapic_gsi_routing(ioapic);
 141
 142	return gsi_cfg->gsi_end - gsi_cfg->gsi_base + 1;
 143}
 144
 145static inline u32 mp_pin_to_gsi(int ioapic, int pin)
 146{
 147	return mp_ioapic_gsi_routing(ioapic)->gsi_base + pin;
 148}
 149
 150static inline bool mp_is_legacy_irq(int irq)
 151{
 152	return irq >= 0 && irq < nr_legacy_irqs();
 153}
 154
 155static inline struct irq_domain *mp_ioapic_irqdomain(int ioapic)
 156{
 157	return ioapics[ioapic].irqdomain;
 158}
 159
 160int nr_ioapics;
 161
 162/* The one past the highest gsi number used */
 163u32 gsi_top;
 164
 165/* MP IRQ source entries */
 166struct mpc_intsrc mp_irqs[MAX_IRQ_SOURCES];
 167
 168/* # of MP IRQ source entries */
 169int mp_irq_entries;
 170
 171#ifdef CONFIG_EISA
 172int mp_bus_id_to_type[MAX_MP_BUSSES];
 173#endif
 174
 175DECLARE_BITMAP(mp_bus_not_pci, MAX_MP_BUSSES);
 176
 177bool ioapic_is_disabled __ro_after_init;
 178
 179/**
 180 * disable_ioapic_support() - disables ioapic support at runtime
 181 */
 182void disable_ioapic_support(void)
 183{
 184#ifdef CONFIG_PCI
 185	noioapicquirk = 1;
 186	noioapicreroute = -1;
 187#endif
 188	ioapic_is_disabled = true;
 189}
 190
 191static int __init parse_noapic(char *str)
 192{
 193	/* disable IO-APIC */
 194	disable_ioapic_support();
 195	return 0;
 196}
 197early_param("noapic", parse_noapic);
 198
 199/* Will be called in mpparse/ACPI codes for saving IRQ info */
 200void mp_save_irq(struct mpc_intsrc *m)
 201{
 202	int i;
 203
 204	apic_pr_verbose("Int: type %d, pol %d, trig %d, bus %02x, IRQ %02x, APIC ID %x, APIC INT %02x\n",
 205			m->irqtype, m->irqflag & 3, (m->irqflag >> 2) & 3, m->srcbus,
 206			m->srcbusirq, m->dstapic, m->dstirq);
 
 207
 208	for (i = 0; i < mp_irq_entries; i++) {
 209		if (!memcmp(&mp_irqs[i], m, sizeof(*m)))
 210			return;
 211	}
 212
 213	memcpy(&mp_irqs[mp_irq_entries], m, sizeof(*m));
 214	if (++mp_irq_entries == MAX_IRQ_SOURCES)
 215		panic("Max # of irq sources exceeded!!\n");
 216}
 217
 218static void alloc_ioapic_saved_registers(int idx)
 219{
 220	size_t size;
 221
 222	if (ioapics[idx].saved_registers)
 223		return;
 224
 225	size = sizeof(struct IO_APIC_route_entry) * ioapics[idx].nr_registers;
 226	ioapics[idx].saved_registers = kzalloc(size, GFP_KERNEL);
 227	if (!ioapics[idx].saved_registers)
 228		pr_err("IOAPIC %d: suspend/resume impossible!\n", idx);
 229}
 230
 231static void free_ioapic_saved_registers(int idx)
 232{
 233	kfree(ioapics[idx].saved_registers);
 234	ioapics[idx].saved_registers = NULL;
 235}
 236
 237int __init arch_early_ioapic_init(void)
 238{
 239	int i;
 240
 241	if (!nr_legacy_irqs())
 242		io_apic_irqs = ~0UL;
 243
 244	for_each_ioapic(i)
 245		alloc_ioapic_saved_registers(i);
 246
 247	return 0;
 248}
 249
 250struct io_apic {
 251	unsigned int index;
 252	unsigned int unused[3];
 253	unsigned int data;
 254	unsigned int unused2[11];
 255	unsigned int eoi;
 256};
 257
 258static __attribute_const__ struct io_apic __iomem *io_apic_base(int idx)
 259{
 260	return (void __iomem *) __fix_to_virt(FIX_IO_APIC_BASE_0 + idx)
 261		+ (mpc_ioapic_addr(idx) & ~PAGE_MASK);
 262}
 263
 264static inline void io_apic_eoi(unsigned int apic, unsigned int vector)
 265{
 266	struct io_apic __iomem *io_apic = io_apic_base(apic);
 267
 268	writel(vector, &io_apic->eoi);
 269}
 270
 271unsigned int native_io_apic_read(unsigned int apic, unsigned int reg)
 272{
 273	struct io_apic __iomem *io_apic = io_apic_base(apic);
 274
 275	writel(reg, &io_apic->index);
 276	return readl(&io_apic->data);
 277}
 278
 279static void io_apic_write(unsigned int apic, unsigned int reg,
 280			  unsigned int value)
 281{
 282	struct io_apic __iomem *io_apic = io_apic_base(apic);
 283
 284	writel(reg, &io_apic->index);
 285	writel(value, &io_apic->data);
 286}
 287
 
 
 
 
 
 288static struct IO_APIC_route_entry __ioapic_read_entry(int apic, int pin)
 289{
 290	struct IO_APIC_route_entry entry;
 291
 292	entry.w1 = io_apic_read(apic, 0x10 + 2 * pin);
 293	entry.w2 = io_apic_read(apic, 0x11 + 2 * pin);
 294
 295	return entry;
 296}
 297
 298static struct IO_APIC_route_entry ioapic_read_entry(int apic, int pin)
 299{
 300	guard(raw_spinlock_irqsave)(&ioapic_lock);
 301	return __ioapic_read_entry(apic, pin);
 
 
 
 
 
 
 302}
 303
 304/*
 305 * When we write a new IO APIC routing entry, we need to write the high
 306 * word first! If the mask bit in the low word is clear, we will enable
 307 * the interrupt, and we need to make sure the entry is fully populated
 308 * before that happens.
 309 */
 310static void __ioapic_write_entry(int apic, int pin, struct IO_APIC_route_entry e)
 311{
 312	io_apic_write(apic, 0x11 + 2*pin, e.w2);
 313	io_apic_write(apic, 0x10 + 2*pin, e.w1);
 
 
 
 314}
 315
 316static void ioapic_write_entry(int apic, int pin, struct IO_APIC_route_entry e)
 317{
 318	guard(raw_spinlock_irqsave)(&ioapic_lock);
 
 
 319	__ioapic_write_entry(apic, pin, e);
 
 320}
 321
 322/*
 323 * When we mask an IO APIC routing entry, we need to write the low
 324 * word first, in order to set the mask bit before we change the
 325 * high bits!
 326 */
 327static void ioapic_mask_entry(int apic, int pin)
 328{
 329	struct IO_APIC_route_entry e = { .masked = true };
 
 330
 331	guard(raw_spinlock_irqsave)(&ioapic_lock);
 332	io_apic_write(apic, 0x10 + 2*pin, e.w1);
 333	io_apic_write(apic, 0x11 + 2*pin, e.w2);
 
 334}
 335
 336/*
 337 * The common case is 1:1 IRQ<->pin mappings. Sometimes there are
 338 * shared ISA-space IRQs, so we have to support them. We are super
 339 * fast in the common case, and fast for shared ISA-space IRQs.
 340 */
 341static bool add_pin_to_irq_node(struct mp_chip_data *data, int node, int apic, int pin)
 
 342{
 343	struct irq_pin_list *entry;
 344
 345	/* Don't allow duplicates */
 346	for_each_irq_pin(entry, data->irq_2_pin) {
 347		if (entry->apic == apic && entry->pin == pin)
 348			return true;
 349	}
 350
 351	entry = kzalloc_node(sizeof(struct irq_pin_list), GFP_ATOMIC, node);
 352	if (!entry) {
 353		pr_err("Cannot allocate irq_pin_list (%d,%d,%d)\n", node, apic, pin);
 354		return false;
 
 355	}
 356
 357	entry->apic = apic;
 358	entry->pin = pin;
 359	list_add_tail(&entry->list, &data->irq_2_pin);
 360	return true;
 
 361}
 362
 363static void __remove_pin_from_irq(struct mp_chip_data *data, int apic, int pin)
 364{
 365	struct irq_pin_list *tmp, *entry;
 366
 367	list_for_each_entry_safe(entry, tmp, &data->irq_2_pin, list) {
 368		if (entry->apic == apic && entry->pin == pin) {
 369			list_del(&entry->list);
 370			kfree(entry);
 371			return;
 372		}
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 373	}
 
 
 
 374}
 375
 376static void io_apic_modify_irq(struct mp_chip_data *data, bool masked,
 
 377			       void (*final)(struct irq_pin_list *entry))
 378{
 
 379	struct irq_pin_list *entry;
 380
 381	data->entry.masked = masked;
 
 
 
 382
 383	for_each_irq_pin(entry, data->irq_2_pin) {
 384		io_apic_write(entry->apic, 0x10 + 2 * entry->pin, data->entry.w1);
 385		if (final)
 386			final(entry);
 387	}
 388}
 389
 390/*
 391 * Synchronize the IO-APIC and the CPU by doing a dummy read from the
 392 * IO-APIC
 393 */
 394static void io_apic_sync(struct irq_pin_list *entry)
 395{
 
 
 
 
 396	struct io_apic __iomem *io_apic;
 397
 398	io_apic = io_apic_base(entry->apic);
 399	readl(&io_apic->data);
 400}
 401
 402static void mask_ioapic_irq(struct irq_data *irq_data)
 403{
 404	struct mp_chip_data *data = irq_data->chip_data;
 
 405
 406	guard(raw_spinlock_irqsave)(&ioapic_lock);
 407	io_apic_modify_irq(data, true, &io_apic_sync);
 
 408}
 409
 410static void __unmask_ioapic(struct mp_chip_data *data)
 411{
 412	io_apic_modify_irq(data, false, NULL);
 413}
 414
 415static void unmask_ioapic_irq(struct irq_data *irq_data)
 416{
 417	struct mp_chip_data *data = irq_data->chip_data;
 
 418
 419	guard(raw_spinlock_irqsave)(&ioapic_lock);
 420	__unmask_ioapic(data);
 
 421}
 422
 423/*
 424 * IO-APIC versions below 0x20 don't support EOI register.
 425 * For the record, here is the information about various versions:
 426 *     0Xh     82489DX
 427 *     1Xh     I/OAPIC or I/O(x)APIC which are not PCI 2.2 Compliant
 428 *     2Xh     I/O(x)APIC which is PCI 2.2 Compliant
 429 *     30h-FFh Reserved
 430 *
 431 * Some of the Intel ICH Specs (ICH2 to ICH5) documents the io-apic
 432 * version as 0x2. This is an error with documentation and these ICH chips
 433 * use io-apic's of version 0x20.
 434 *
 435 * For IO-APIC's with EOI register, we use that to do an explicit EOI.
 436 * Otherwise, we simulate the EOI message manually by changing the trigger
 437 * mode to edge and then back to level, with RTE being masked during this.
 438 */
 439static void __eoi_ioapic_pin(int apic, int pin, int vector)
 440{
 441	if (mpc_ioapic_ver(apic) >= 0x20) {
 442		io_apic_eoi(apic, vector);
 443	} else {
 444		struct IO_APIC_route_entry entry, entry1;
 445
 446		entry = entry1 = __ioapic_read_entry(apic, pin);
 447
 448		/* Mask the entry and change the trigger mode to edge. */
 449		entry1.masked = true;
 450		entry1.is_level = false;
 
 
 451
 452		__ioapic_write_entry(apic, pin, entry1);
 453
 454		/* Restore the previous level triggered entry. */
 
 
 455		__ioapic_write_entry(apic, pin, entry);
 456	}
 457}
 458
 459static void eoi_ioapic_pin(int vector, struct mp_chip_data *data)
 460{
 
 461	struct irq_pin_list *entry;
 462
 463	guard(raw_spinlock_irqsave)(&ioapic_lock);
 464	for_each_irq_pin(entry, data->irq_2_pin)
 465		__eoi_ioapic_pin(entry->apic, entry->pin, vector);
 
 466}
 467
 468static void clear_IO_APIC_pin(unsigned int apic, unsigned int pin)
 469{
 470	struct IO_APIC_route_entry entry;
 471
 472	/* Check delivery_mode to be sure we're not clearing an SMI pin */
 473	entry = ioapic_read_entry(apic, pin);
 474	if (entry.delivery_mode == APIC_DELIVERY_MODE_SMI)
 475		return;
 476
 477	/*
 478	 * Make sure the entry is masked and re-read the contents to check
 479	 * if it is a level triggered pin and if the remote-IRR is set.
 480	 */
 481	if (!entry.masked) {
 482		entry.masked = true;
 483		ioapic_write_entry(apic, pin, entry);
 484		entry = ioapic_read_entry(apic, pin);
 485	}
 486
 487	if (entry.irr) {
 
 
 488		/*
 489		 * Make sure the trigger mode is set to level. Explicit EOI
 490		 * doesn't clear the remote-IRR if the trigger mode is not
 491		 * set to level.
 492		 */
 493		if (!entry.is_level) {
 494			entry.is_level = true;
 495			ioapic_write_entry(apic, pin, entry);
 496		}
 497		guard(raw_spinlock_irqsave)(&ioapic_lock);
 498		__eoi_ioapic_pin(apic, pin, entry.vector);
 
 499	}
 500
 501	/*
 502	 * Clear the rest of the bits in the IO-APIC RTE except for the mask
 503	 * bit.
 504	 */
 505	ioapic_mask_entry(apic, pin);
 506	entry = ioapic_read_entry(apic, pin);
 507	if (entry.irr)
 508		pr_err("Unable to reset IRR for apic: %d, pin :%d\n",
 509		       mpc_ioapic_id(apic), pin);
 510}
 511
 512void clear_IO_APIC (void)
 513{
 514	int apic, pin;
 515
 516	for_each_ioapic_pin(apic, pin)
 517		clear_IO_APIC_pin(apic, pin);
 518}
 519
 520#ifdef CONFIG_X86_32
 521/*
 522 * support for broken MP BIOSs, enables hand-redirection of PIRQ0-7 to
 523 * specific CPU-side IRQs.
 524 */
 525
 526#define MAX_PIRQS 8
 527static int pirq_entries[MAX_PIRQS] = {
 528	[0 ... MAX_PIRQS - 1] = -1
 529};
 530
 531static int __init ioapic_pirq_setup(char *str)
 532{
 533	int i, max, ints[MAX_PIRQS+1];
 
 534
 535	get_options(str, ARRAY_SIZE(ints), ints);
 536
 537	apic_pr_verbose("PIRQ redirection, working around broken MP-BIOS.\n");
 538
 539	max = MAX_PIRQS;
 540	if (ints[0] < MAX_PIRQS)
 541		max = ints[0];
 542
 543	for (i = 0; i < max; i++) {
 544		apic_pr_verbose("... PIRQ%d -> IRQ %d\n", i, ints[i + 1]);
 545		/* PIRQs are mapped upside down, usually */
 
 
 
 546		pirq_entries[MAX_PIRQS-i-1] = ints[i+1];
 547	}
 548	return 1;
 549}
 
 550__setup("pirq=", ioapic_pirq_setup);
 551#endif /* CONFIG_X86_32 */
 552
 553/*
 554 * Saves all the IO-APIC RTE's
 555 */
 556int save_ioapic_entries(void)
 557{
 558	int apic, pin;
 559	int err = 0;
 560
 561	for_each_ioapic(apic) {
 562		if (!ioapics[apic].saved_registers) {
 563			err = -ENOMEM;
 564			continue;
 565		}
 566
 567		for_each_pin(apic, pin)
 568			ioapics[apic].saved_registers[pin] = ioapic_read_entry(apic, pin);
 
 569	}
 570
 571	return err;
 572}
 573
 574/*
 575 * Mask all IO APIC entries.
 576 */
 577void mask_ioapic_entries(void)
 578{
 579	int apic, pin;
 580
 581	for_each_ioapic(apic) {
 582		if (!ioapics[apic].saved_registers)
 583			continue;
 584
 585		for_each_pin(apic, pin) {
 586			struct IO_APIC_route_entry entry;
 587
 588			entry = ioapics[apic].saved_registers[pin];
 589			if (!entry.masked) {
 590				entry.masked = true;
 591				ioapic_write_entry(apic, pin, entry);
 592			}
 593		}
 594	}
 595}
 596
 597/*
 598 * Restore IO APIC entries which was saved in the ioapic structure.
 599 */
 600int restore_ioapic_entries(void)
 601{
 602	int apic, pin;
 603
 604	for_each_ioapic(apic) {
 605		if (!ioapics[apic].saved_registers)
 606			continue;
 607
 608		for_each_pin(apic, pin)
 609			ioapic_write_entry(apic, pin, ioapics[apic].saved_registers[pin]);
 
 610	}
 611	return 0;
 612}
 613
 614/*
 615 * Find the IRQ entry number of a certain pin.
 616 */
 617static int find_irq_entry(int ioapic_idx, int pin, int type)
 618{
 619	int i;
 620
 621	for (i = 0; i < mp_irq_entries; i++) {
 622		if (mp_irqs[i].irqtype == type &&
 623		    (mp_irqs[i].dstapic == mpc_ioapic_id(ioapic_idx) ||
 624		     mp_irqs[i].dstapic == MP_APIC_ALL) &&
 625		    mp_irqs[i].dstirq == pin)
 626			return i;
 627	}
 628
 629	return -1;
 630}
 631
 632/*
 633 * Find the pin to which IRQ[irq] (ISA) is connected
 634 */
 635static int __init find_isa_irq_pin(int irq, int type)
 636{
 637	int i;
 638
 639	for (i = 0; i < mp_irq_entries; i++) {
 640		int lbus = mp_irqs[i].srcbus;
 641
 642		if (test_bit(lbus, mp_bus_not_pci) && (mp_irqs[i].irqtype == type) &&
 
 643		    (mp_irqs[i].srcbusirq == irq))
 
 644			return mp_irqs[i].dstirq;
 645	}
 646	return -1;
 647}
 648
 649static int __init find_isa_irq_apic(int irq, int type)
 650{
 651	int i;
 652
 653	for (i = 0; i < mp_irq_entries; i++) {
 654		int lbus = mp_irqs[i].srcbus;
 655
 656		if (test_bit(lbus, mp_bus_not_pci) && (mp_irqs[i].irqtype == type) &&
 
 657		    (mp_irqs[i].srcbusirq == irq))
 658			break;
 659	}
 660
 661	if (i < mp_irq_entries) {
 662		int ioapic_idx;
 663
 664		for_each_ioapic(ioapic_idx) {
 665			if (mpc_ioapic_id(ioapic_idx) == mp_irqs[i].dstapic)
 666				return ioapic_idx;
 667		}
 668	}
 669
 670	return -1;
 671}
 672
 673static bool irq_active_low(int idx)
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 674{
 675	int bus = mp_irqs[idx].srcbus;
 676
 677	/*
 678	 * Determine IRQ line polarity (high active or low active):
 679	 */
 680	switch (mp_irqs[idx].irqflag & MP_IRQPOL_MASK) {
 681	case MP_IRQPOL_DEFAULT:
 682		/*
 683		 * Conforms to spec, ie. bus-type dependent polarity.  PCI
 684		 * defaults to low active. [E]ISA defaults to high active.
 685		 */
 686		return !test_bit(bus, mp_bus_not_pci);
 687	case MP_IRQPOL_ACTIVE_HIGH:
 688		return false;
 689	case MP_IRQPOL_RESERVED:
 690		pr_warn("IOAPIC: Invalid polarity: 2, defaulting to low\n");
 691		fallthrough;
 692	case MP_IRQPOL_ACTIVE_LOW:
 693	default: /* Pointless default required due to do gcc stupidity */
 694		return true;
 695	}
 696}
 697
 698#ifdef CONFIG_EISA
 699/*
 700 * EISA Edge/Level control register, ELCR
 701 */
 702static bool EISA_ELCR(unsigned int irq)
 703{
 704	if (irq < nr_legacy_irqs()) {
 705		unsigned int port = PIC_ELCR1 + (irq >> 3);
 706		return (inb(port) >> (irq & 7)) & 1;
 707	}
 708	apic_pr_verbose("Broken MPtable reports ISA irq %d\n", irq);
 709	return false;
 710}
 711
 712/*
 713 * EISA interrupts are always active high and can be edge or level
 714 * triggered depending on the ELCR value.  If an interrupt is listed as
 715 * EISA conforming in the MP table, that means its trigger type must be
 716 * read in from the ELCR.
 717 */
 718static bool eisa_irq_is_level(int idx, int bus, bool level)
 719{
 720	switch (mp_bus_id_to_type[bus]) {
 721	case MP_BUS_PCI:
 722	case MP_BUS_ISA:
 723		return level;
 724	case MP_BUS_EISA:
 725		return EISA_ELCR(mp_irqs[idx].srcbusirq);
 726	}
 727	pr_warn("IOAPIC: Invalid srcbus: %d defaulting to level\n", bus);
 728	return true;
 729}
 730#else
 731static inline int eisa_irq_is_level(int idx, int bus, bool level)
 732{
 733	return level;
 734}
 735#endif
 736
 737static bool irq_is_level(int idx)
 738{
 739	int bus = mp_irqs[idx].srcbus;
 740	bool level;
 741
 742	/*
 743	 * Determine IRQ trigger mode (edge or level sensitive):
 744	 */
 745	switch (mp_irqs[idx].irqflag & MP_IRQTRIG_MASK) {
 746	case MP_IRQTRIG_DEFAULT:
 747		/*
 748		 * Conforms to spec, ie. bus-type dependent trigger
 749		 * mode. PCI defaults to level, ISA to edge.
 750		 */
 751		level = !test_bit(bus, mp_bus_not_pci);
 752		/* Take EISA into account */
 753		return eisa_irq_is_level(idx, bus, level);
 754	case MP_IRQTRIG_EDGE:
 755		return false;
 756	case MP_IRQTRIG_RESERVED:
 757		pr_warn("IOAPIC: Invalid trigger mode 2 defaulting to level\n");
 758		fallthrough;
 759	case MP_IRQTRIG_LEVEL:
 760	default: /* Pointless default required due to do gcc stupidity */
 761		return true;
 762	}
 763}
 764
 765static int __acpi_get_override_irq(u32 gsi, bool *trigger, bool *polarity)
 766{
 767	int ioapic, pin, idx;
 768
 769	if (ioapic_is_disabled)
 770		return -1;
 771
 772	ioapic = mp_find_ioapic(gsi);
 773	if (ioapic < 0)
 774		return -1;
 775
 776	pin = mp_find_ioapic_pin(ioapic, gsi);
 777	if (pin < 0)
 778		return -1;
 779
 780	idx = find_irq_entry(ioapic, pin, mp_INT);
 781	if (idx < 0)
 782		return -1;
 783
 784	*trigger = irq_is_level(idx);
 785	*polarity = irq_active_low(idx);
 786	return 0;
 787}
 788
 789#ifdef CONFIG_ACPI
 790int acpi_get_override_irq(u32 gsi, int *is_level, int *active_low)
 791{
 792	*is_level = *active_low = 0;
 793	return __acpi_get_override_irq(gsi, (bool *)is_level,
 794				       (bool *)active_low);
 795}
 796#endif
 797
 798void ioapic_set_alloc_attr(struct irq_alloc_info *info, int node,
 799			   int trigger, int polarity)
 800{
 801	init_irq_alloc_info(info, NULL);
 802	info->type = X86_IRQ_ALLOC_TYPE_IOAPIC;
 803	info->ioapic.node = node;
 804	info->ioapic.is_level = trigger;
 805	info->ioapic.active_low = polarity;
 806	info->ioapic.valid = 1;
 807}
 808
 
 
 
 
 809static void ioapic_copy_alloc_attr(struct irq_alloc_info *dst,
 810				   struct irq_alloc_info *src,
 811				   u32 gsi, int ioapic_idx, int pin)
 812{
 813	bool level, pol_low;
 814
 815	copy_irq_alloc_info(dst, src);
 816	dst->type = X86_IRQ_ALLOC_TYPE_IOAPIC;
 817	dst->devid = mpc_ioapic_id(ioapic_idx);
 818	dst->ioapic.pin = pin;
 819	dst->ioapic.valid = 1;
 820	if (src && src->ioapic.valid) {
 821		dst->ioapic.node = src->ioapic.node;
 822		dst->ioapic.is_level = src->ioapic.is_level;
 823		dst->ioapic.active_low = src->ioapic.active_low;
 824	} else {
 825		dst->ioapic.node = NUMA_NO_NODE;
 826		if (__acpi_get_override_irq(gsi, &level, &pol_low) >= 0) {
 827			dst->ioapic.is_level = level;
 828			dst->ioapic.active_low = pol_low;
 829		} else {
 830			/*
 831			 * PCI interrupts are always active low level
 832			 * triggered.
 833			 */
 834			dst->ioapic.is_level = true;
 835			dst->ioapic.active_low = true;
 836		}
 837	}
 838}
 839
 840static int ioapic_alloc_attr_node(struct irq_alloc_info *info)
 841{
 842	return (info && info->ioapic.valid) ? info->ioapic.node : NUMA_NO_NODE;
 843}
 844
 845static void mp_register_handler(unsigned int irq, bool level)
 846{
 847	irq_flow_handler_t hdl;
 848	bool fasteoi;
 849
 850	if (level) {
 851		irq_set_status_flags(irq, IRQ_LEVEL);
 852		fasteoi = true;
 853	} else {
 854		irq_clear_status_flags(irq, IRQ_LEVEL);
 855		fasteoi = false;
 856	}
 857
 858	hdl = fasteoi ? handle_fasteoi_irq : handle_edge_irq;
 859	__irq_set_handler(irq, hdl, 0, fasteoi ? "fasteoi" : "edge");
 860}
 861
 862static bool mp_check_pin_attr(int irq, struct irq_alloc_info *info)
 863{
 864	struct mp_chip_data *data = irq_get_chip_data(irq);
 865
 866	/*
 867	 * setup_IO_APIC_irqs() programs all legacy IRQs with default trigger
 868	 * and polarity attributes. So allow the first user to reprogram the
 869	 * pin with real trigger and polarity attributes.
 870	 */
 871	if (irq < nr_legacy_irqs() && data->count == 1) {
 872		if (info->ioapic.is_level != data->is_level)
 873			mp_register_handler(irq, info->ioapic.is_level);
 874		data->entry.is_level = data->is_level = info->ioapic.is_level;
 875		data->entry.active_low = data->active_low = info->ioapic.active_low;
 876	}
 877
 878	return data->is_level == info->ioapic.is_level &&
 879	       data->active_low == info->ioapic.active_low;
 880}
 881
 882static int alloc_irq_from_domain(struct irq_domain *domain, int ioapic, u32 gsi,
 883				 struct irq_alloc_info *info)
 884{
 885	int type = ioapics[ioapic].irqdomain_cfg.type;
 886	bool legacy = false;
 887	int irq = -1;
 
 888
 889	switch (type) {
 890	case IOAPIC_DOMAIN_LEGACY:
 891		/*
 892		 * Dynamically allocate IRQ number for non-ISA IRQs in the first
 893		 * 16 GSIs on some weird platforms.
 894		 */
 895		if (!ioapic_initialized || gsi >= nr_legacy_irqs())
 896			irq = gsi;
 897		legacy = mp_is_legacy_irq(irq);
 898		break;
 899	case IOAPIC_DOMAIN_STRICT:
 900		irq = gsi;
 901		break;
 902	case IOAPIC_DOMAIN_DYNAMIC:
 903		break;
 904	default:
 905		WARN(1, "ioapic: unknown irqdomain type %d\n", type);
 906		return -1;
 907	}
 908
 909	return __irq_domain_alloc_irqs(domain, irq, 1, ioapic_alloc_attr_node(info),
 
 910				       info, legacy, NULL);
 911}
 912
 913/*
 914 * Need special handling for ISA IRQs because there may be multiple IOAPIC pins
 915 * sharing the same ISA IRQ number and irqdomain only supports 1:1 mapping
 916 * between IOAPIC pin and IRQ number. A typical IOAPIC has 24 pins, pin 0-15 are
 917 * used for legacy IRQs and pin 16-23 are used for PCI IRQs (PIRQ A-H).
 918 * When ACPI is disabled, only legacy IRQ numbers (IRQ0-15) are available, and
 919 * some BIOSes may use MP Interrupt Source records to override IRQ numbers for
 920 * PIRQs instead of reprogramming the interrupt routing logic. Thus there may be
 921 * multiple pins sharing the same legacy IRQ number when ACPI is disabled.
 922 */
 923static int alloc_isa_irq_from_domain(struct irq_domain *domain, int irq, int ioapic, int pin,
 
 924				     struct irq_alloc_info *info)
 925{
 
 926	struct irq_data *irq_data = irq_get_irq_data(irq);
 927	int node = ioapic_alloc_attr_node(info);
 928	struct mp_chip_data *data;
 929
 930	/*
 931	 * Legacy ISA IRQ has already been allocated, just add pin to
 932	 * the pin list associated with this IRQ and program the IOAPIC
 933	 * entry.
 934	 */
 935	if (irq_data && irq_data->parent_data) {
 936		if (!mp_check_pin_attr(irq, info))
 937			return -EBUSY;
 938		if (!add_pin_to_irq_node(irq_data->chip_data, node, ioapic, info->ioapic.pin))
 
 939			return -ENOMEM;
 940	} else {
 941		info->flags |= X86_IRQ_ALLOC_LEGACY;
 942		irq = __irq_domain_alloc_irqs(domain, irq, 1, node, info, true, NULL);
 
 943		if (irq >= 0) {
 944			irq_data = irq_domain_get_irq_data(domain, irq);
 945			data = irq_data->chip_data;
 946			data->isa_irq = true;
 947		}
 948	}
 949
 950	return irq;
 951}
 952
 953static int mp_map_pin_to_irq(u32 gsi, int idx, int ioapic, int pin,
 954			     unsigned int flags, struct irq_alloc_info *info)
 955{
 956	struct irq_domain *domain = mp_ioapic_irqdomain(ioapic);
 
 957	struct irq_alloc_info tmp;
 958	struct mp_chip_data *data;
 959	bool legacy = false;
 960	int irq;
 961
 962	if (!domain)
 963		return -ENOSYS;
 964
 965	if (idx >= 0 && test_bit(mp_irqs[idx].srcbus, mp_bus_not_pci)) {
 966		irq = mp_irqs[idx].srcbusirq;
 967		legacy = mp_is_legacy_irq(irq);
 968		/*
 969		 * IRQ2 is unusable for historical reasons on systems which
 970		 * have a legacy PIC. See the comment vs. IRQ2 further down.
 971		 *
 972		 * If this gets removed at some point then the related code
 973		 * in lapic_assign_system_vectors() needs to be adjusted as
 974		 * well.
 975		 */
 976		if (legacy && irq == PIC_CASCADE_IR)
 977			return -EINVAL;
 978	}
 979
 980	guard(mutex)(&ioapic_mutex);
 981	if (!(flags & IOAPIC_MAP_ALLOC)) {
 982		if (!legacy) {
 983			irq = irq_find_mapping(domain, pin);
 984			if (irq == 0)
 985				irq = -ENOENT;
 986		}
 987	} else {
 988		ioapic_copy_alloc_attr(&tmp, info, gsi, ioapic, pin);
 989		if (legacy)
 990			irq = alloc_isa_irq_from_domain(domain, irq,
 991							ioapic, pin, &tmp);
 992		else if ((irq = irq_find_mapping(domain, pin)) == 0)
 993			irq = alloc_irq_from_domain(domain, ioapic, gsi, &tmp);
 994		else if (!mp_check_pin_attr(irq, &tmp))
 995			irq = -EBUSY;
 996		if (irq >= 0) {
 997			data = irq_get_chip_data(irq);
 998			data->count++;
 999		}
1000	}
 
 
1001	return irq;
1002}
1003
1004static int pin_2_irq(int idx, int ioapic, int pin, unsigned int flags)
1005{
1006	u32 gsi = mp_pin_to_gsi(ioapic, pin);
1007
1008	/* Debugging check, we are in big trouble if this message pops up! */
 
 
1009	if (mp_irqs[idx].dstirq != pin)
1010		pr_err("broken BIOS or MPTABLE parser, ayiee!!\n");
1011
1012#ifdef CONFIG_X86_32
1013	/* PCI IRQ command line redirection. Yes, limits are hardcoded. */
 
 
1014	if ((pin >= 16) && (pin <= 23)) {
1015		if (pirq_entries[pin - 16] != -1) {
1016			if (!pirq_entries[pin - 16]) {
1017				apic_pr_verbose("Disabling PIRQ%d\n", pin - 16);
 
1018			} else {
1019				int irq = pirq_entries[pin-16];
1020
1021				apic_pr_verbose("Using PIRQ%d -> IRQ %d\n", pin - 16, irq);
 
1022				return irq;
1023			}
1024		}
1025	}
1026#endif
1027
1028	return  mp_map_pin_to_irq(gsi, idx, ioapic, pin, flags, NULL);
1029}
1030
1031int mp_map_gsi_to_irq(u32 gsi, unsigned int flags, struct irq_alloc_info *info)
1032{
1033	int ioapic, pin, idx;
1034
1035	ioapic = mp_find_ioapic(gsi);
1036	if (ioapic < 0)
1037		return -ENODEV;
1038
1039	pin = mp_find_ioapic_pin(ioapic, gsi);
1040	idx = find_irq_entry(ioapic, pin, mp_INT);
1041	if ((flags & IOAPIC_MAP_CHECK) && idx < 0)
1042		return -ENODEV;
1043
1044	return mp_map_pin_to_irq(gsi, idx, ioapic, pin, flags, info);
1045}
1046
1047void mp_unmap_irq(int irq)
1048{
1049	struct irq_data *irq_data = irq_get_irq_data(irq);
1050	struct mp_chip_data *data;
1051
1052	if (!irq_data || !irq_data->domain)
1053		return;
1054
1055	data = irq_data->chip_data;
1056	if (!data || data->isa_irq)
1057		return;
1058
1059	guard(mutex)(&ioapic_mutex);
1060	if (--data->count == 0)
1061		irq_domain_free_irqs(irq, 1);
 
1062}
1063
1064/*
1065 * Find a specific PCI IRQ entry.
1066 * Not an __init, possibly needed by modules
1067 */
1068int IO_APIC_get_PCI_irq_vector(int bus, int slot, int pin)
1069{
1070	int irq, i, best_ioapic = -1, best_idx = -1;
1071
1072	apic_pr_debug("Querying PCI -> IRQ mapping bus:%d, slot:%d, pin:%d.\n",
1073		      bus, slot, pin);
 
1074	if (test_bit(bus, mp_bus_not_pci)) {
1075		apic_pr_verbose("PCI BIOS passed nonexistent PCI bus %d!\n", bus);
 
1076		return -1;
1077	}
1078
1079	for (i = 0; i < mp_irq_entries; i++) {
1080		int lbus = mp_irqs[i].srcbus;
1081		int ioapic_idx, found = 0;
1082
1083		if (bus != lbus || mp_irqs[i].irqtype != mp_INT ||
1084		    slot != ((mp_irqs[i].srcbusirq >> 2) & 0x1f))
1085			continue;
1086
1087		for_each_ioapic(ioapic_idx)
1088			if (mpc_ioapic_id(ioapic_idx) == mp_irqs[i].dstapic ||
1089			    mp_irqs[i].dstapic == MP_APIC_ALL) {
1090				found = 1;
1091				break;
1092			}
1093		if (!found)
1094			continue;
1095
1096		/* Skip ISA IRQs */
1097		irq = pin_2_irq(i, ioapic_idx, mp_irqs[i].dstirq, 0);
1098		if (irq > 0 && !IO_APIC_IRQ(irq))
1099			continue;
1100
1101		if (pin == (mp_irqs[i].srcbusirq & 3)) {
1102			best_idx = i;
1103			best_ioapic = ioapic_idx;
1104			goto out;
1105		}
1106
1107		/*
1108		 * Use the first all-but-pin matching entry as a
1109		 * best-guess fuzzy result for broken mptables.
1110		 */
1111		if (best_idx < 0) {
1112			best_idx = i;
1113			best_ioapic = ioapic_idx;
1114		}
1115	}
1116	if (best_idx < 0)
1117		return -1;
1118
1119out:
1120	return pin_2_irq(best_idx, best_ioapic, mp_irqs[best_idx].dstirq, IOAPIC_MAP_ALLOC);
 
1121}
1122EXPORT_SYMBOL(IO_APIC_get_PCI_irq_vector);
1123
1124static struct irq_chip ioapic_chip, ioapic_ir_chip;
1125
1126static void __init setup_IO_APIC_irqs(void)
1127{
1128	unsigned int ioapic, pin;
1129	int idx;
1130
1131	apic_pr_verbose("Init IO_APIC IRQs\n");
1132
1133	for_each_ioapic_pin(ioapic, pin) {
1134		idx = find_irq_entry(ioapic, pin, mp_INT);
1135		if (idx < 0) {
1136			apic_pr_verbose("apic %d pin %d not connected\n",
1137					mpc_ioapic_id(ioapic), pin);
1138		} else {
1139			pin_2_irq(idx, ioapic, pin, ioapic ? 0 : IOAPIC_MAP_ALLOC);
1140		}
 
1141	}
1142}
1143
1144void ioapic_zap_locks(void)
1145{
1146	raw_spin_lock_init(&ioapic_lock);
1147}
1148
1149static void io_apic_print_entries(unsigned int apic, unsigned int nr_entries)
1150{
1151	struct IO_APIC_route_entry entry;
1152	char buf[256];
1153	int i;
 
 
 
1154
1155	apic_dbg("IOAPIC %d:\n", apic);
1156	for (i = 0; i <= nr_entries; i++) {
1157		entry = ioapic_read_entry(apic, i);
1158		snprintf(buf, sizeof(buf), " pin%02x, %s, %s, %s, V(%02X), IRR(%1d), S(%1d)",
1159			 i, entry.masked ? "disabled" : "enabled ",
1160			 entry.is_level ? "level" : "edge ",
1161			 entry.active_low ? "low " : "high",
 
 
1162			 entry.vector, entry.irr, entry.delivery_status);
1163		if (entry.ir_format) {
1164			apic_dbg("%s, remapped, I(%04X),  Z(%X)\n", buf,
1165				 (entry.ir_index_15 << 15) | entry.ir_index_0_14, entry.ir_zero);
1166		} else {
1167			apic_dbg("%s, %s, D(%02X%02X), M(%1d)\n", buf,
1168				 entry.dest_mode_logical ? "logical " : "physic	al",
1169				 entry.virt_destid_8_14, entry.destid_0_7, entry.delivery_mode);
1170		}
 
 
1171	}
1172}
1173
1174static void __init print_IO_APIC(int ioapic_idx)
1175{
1176	union IO_APIC_reg_00 reg_00;
1177	union IO_APIC_reg_01 reg_01;
1178	union IO_APIC_reg_02 reg_02;
1179	union IO_APIC_reg_03 reg_03;
 
1180
1181	scoped_guard (raw_spinlock_irqsave, &ioapic_lock) {
1182		reg_00.raw = io_apic_read(ioapic_idx, 0);
1183		reg_01.raw = io_apic_read(ioapic_idx, 1);
1184		if (reg_01.bits.version >= 0x10)
1185			reg_02.raw = io_apic_read(ioapic_idx, 2);
1186		if (reg_01.bits.version >= 0x20)
1187			reg_03.raw = io_apic_read(ioapic_idx, 3);
1188	}
1189
1190	apic_dbg("IO APIC #%d......\n", mpc_ioapic_id(ioapic_idx));
1191	apic_dbg(".... register #00: %08X\n", reg_00.raw);
1192	apic_dbg(".......    : physical APIC id: %02X\n", reg_00.bits.ID);
1193	apic_dbg(".......    : Delivery Type: %X\n", reg_00.bits.delivery_type);
1194	apic_dbg(".......    : LTS          : %X\n", reg_00.bits.LTS);
1195	apic_dbg(".... register #01: %08X\n", *(int *)&reg_01);
1196	apic_dbg(".......     : max redirection entries: %02X\n", reg_01.bits.entries);
1197	apic_dbg(".......     : PRQ implemented: %X\n", reg_01.bits.PRQ);
1198	apic_dbg(".......     : IO APIC version: %02X\n", reg_01.bits.version);
 
 
 
 
1199
1200	/*
1201	 * Some Intel chipsets with IO APIC VERSION of 0x1? don't have reg_02,
1202	 * but the value of reg_02 is read as the previous read register
1203	 * value, so ignore it if reg_02 == reg_01.
1204	 */
1205	if (reg_01.bits.version >= 0x10 && reg_02.raw != reg_01.raw) {
1206		apic_dbg(".... register #02: %08X\n", reg_02.raw);
1207		apic_dbg(".......     : arbitration: %02X\n", reg_02.bits.arbitration);
1208	}
1209
1210	/*
1211	 * Some Intel chipsets with IO APIC VERSION of 0x2? don't have reg_02
1212	 * or reg_03, but the value of reg_0[23] is read as the previous read
1213	 * register value, so ignore it if reg_03 == reg_0[12].
1214	 */
1215	if (reg_01.bits.version >= 0x20 && reg_03.raw != reg_02.raw &&
1216	    reg_03.raw != reg_01.raw) {
1217		apic_dbg(".... register #03: %08X\n", reg_03.raw);
1218		apic_dbg(".......     : Boot DT    : %X\n", reg_03.bits.boot_DT);
1219	}
1220
1221	apic_dbg(".... IRQ redirection table:\n");
1222	io_apic_print_entries(ioapic_idx, reg_01.bits.entries);
1223}
1224
1225void __init print_IO_APICs(void)
1226{
1227	int ioapic_idx;
1228	unsigned int irq;
1229
1230	apic_dbg("number of MP IRQ sources: %d.\n", mp_irq_entries);
1231	for_each_ioapic(ioapic_idx) {
1232		apic_dbg("number of IO-APIC #%d registers: %d.\n",
1233			 mpc_ioapic_id(ioapic_idx), ioapics[ioapic_idx].nr_registers);
1234	}
1235
1236	/*
1237	 * We are a bit conservative about what we expect.  We have to
1238	 * know about every hardware change ASAP.
1239	 */
1240	printk(KERN_INFO "testing the IO APIC.......................\n");
1241
1242	for_each_ioapic(ioapic_idx)
1243		print_IO_APIC(ioapic_idx);
1244
1245	apic_dbg("IRQ to pin mappings:\n");
1246	for_each_active_irq(irq) {
1247		struct irq_pin_list *entry;
1248		struct irq_chip *chip;
1249		struct mp_chip_data *data;
1250
1251		chip = irq_get_chip(irq);
1252		if (chip != &ioapic_chip && chip != &ioapic_ir_chip)
1253			continue;
1254		data = irq_get_chip_data(irq);
1255		if (!data)
1256			continue;
1257		if (list_empty(&data->irq_2_pin))
1258			continue;
1259
1260		apic_dbg("IRQ%d ", irq);
1261		for_each_irq_pin(entry, data->irq_2_pin)
1262			pr_cont("-> %d:%d", entry->apic, entry->pin);
1263		pr_cont("\n");
1264	}
1265
1266	printk(KERN_INFO ".................................... done.\n");
1267}
1268
1269/* Where if anywhere is the i8259 connect in external int mode */
1270static struct { int pin, apic; } ioapic_i8259 = { -1, -1 };
1271
1272void __init enable_IO_APIC(void)
1273{
1274	int i8259_apic, i8259_pin, apic, pin;
 
1275
1276	if (ioapic_is_disabled)
1277		nr_ioapics = 0;
1278
1279	if (!nr_legacy_irqs() || !nr_ioapics)
1280		return;
1281
1282	for_each_ioapic_pin(apic, pin) {
1283		/* See if any of the pins is in ExtINT mode */
1284		struct IO_APIC_route_entry entry = ioapic_read_entry(apic, pin);
1285
1286		/*
1287		 * If the interrupt line is enabled and in ExtInt mode I
1288		 * have found the pin where the i8259 is connected.
1289		 */
1290		if (!entry.masked && entry.delivery_mode == APIC_DELIVERY_MODE_EXTINT) {
1291			ioapic_i8259.apic = apic;
1292			ioapic_i8259.pin  = pin;
1293			break;
1294		}
1295	}
1296
1297	/*
1298	 * Look to see what if the MP table has reported the ExtINT
1299	 *
1300	 * If we could not find the appropriate pin by looking at the ioapic
1301	 * the i8259 probably is not connected the ioapic but give the
1302	 * mptable a chance anyway.
1303	 */
1304	i8259_pin  = find_isa_irq_pin(0, mp_ExtINT);
1305	i8259_apic = find_isa_irq_apic(0, mp_ExtINT);
1306	/* Trust the MP table if nothing is setup in the hardware */
1307	if ((ioapic_i8259.pin == -1) && (i8259_pin >= 0)) {
1308		pr_warn("ExtINT not setup in hardware but reported by MP table\n");
1309		ioapic_i8259.pin  = i8259_pin;
1310		ioapic_i8259.apic = i8259_apic;
1311	}
1312	/* Complain if the MP table and the hardware disagree */
1313	if (((ioapic_i8259.apic != i8259_apic) || (ioapic_i8259.pin != i8259_pin)) &&
1314	    (i8259_pin >= 0) && (ioapic_i8259.pin >= 0))
1315		pr_warn("ExtINT in hardware and MP table differ\n");
 
 
1316
1317	/* Do not trust the IO-APIC being empty at bootup */
 
 
1318	clear_IO_APIC();
1319}
1320
1321void native_restore_boot_irq_mode(void)
1322{
1323	/*
1324	 * If the i8259 is routed through an IOAPIC Put that IOAPIC in
1325	 * virtual wire mode so legacy interrupts can be delivered.
 
1326	 */
1327	if (ioapic_i8259.pin != -1) {
1328		struct IO_APIC_route_entry entry;
1329		u32 apic_id = read_apic_id();
1330
1331		memset(&entry, 0, sizeof(entry));
1332		entry.masked		= false;
1333		entry.is_level		= false;
1334		entry.active_low	= false;
1335		entry.dest_mode_logical	= false;
1336		entry.delivery_mode	= APIC_DELIVERY_MODE_EXTINT;
1337		entry.destid_0_7	= apic_id & 0xFF;
1338		entry.virt_destid_8_14	= apic_id >> 8;
1339
1340		/* Add it to the IO-APIC irq-routing table */
 
 
1341		ioapic_write_entry(ioapic_i8259.apic, ioapic_i8259.pin, entry);
1342	}
1343
1344	if (boot_cpu_has(X86_FEATURE_APIC) || apic_from_smp_config())
1345		disconnect_bsp_APIC(ioapic_i8259.pin != -1);
1346}
1347
1348void restore_boot_irq_mode(void)
1349{
1350	if (!nr_legacy_irqs())
1351		return;
1352
1353	x86_apic_ops.restore();
1354}
1355
1356#ifdef CONFIG_X86_32
1357/*
1358 * function to set the IO-APIC physical IDs based on the
1359 * values stored in the MPC table.
1360 *
1361 * by Matt Domsch <Matt_Domsch@dell.com>  Tue Dec 21 12:25:05 CST 1999
1362 */
1363static void __init setup_ioapic_ids_from_mpc_nocheck(void)
1364{
1365	DECLARE_BITMAP(phys_id_present_map, MAX_LOCAL_APIC);
1366	const u32 broadcast_id = 0xF;
1367	union IO_APIC_reg_00 reg_00;
 
 
 
1368	unsigned char old_id;
1369	int ioapic_idx, i;
1370
1371	/*
1372	 * This is broken; anything with a real cpu count has to
1373	 * circumvent this idiocy regardless.
1374	 */
1375	copy_phys_cpu_present_map(phys_id_present_map);
1376
1377	/*
1378	 * Set the IOAPIC ID to the value stored in the MPC table.
1379	 */
1380	for_each_ioapic(ioapic_idx) {
1381		/* Read the register 0 value */
1382		scoped_guard (raw_spinlock_irqsave, &ioapic_lock)
1383			reg_00.raw = io_apic_read(ioapic_idx, 0);
 
1384
1385		old_id = mpc_ioapic_id(ioapic_idx);
1386
1387		if (mpc_ioapic_id(ioapic_idx) >= broadcast_id) {
1388			pr_err(FW_BUG "IO-APIC#%d ID is %d in the MPC table!...\n",
1389			       ioapic_idx, mpc_ioapic_id(ioapic_idx));
1390			pr_err("... fixing up to %d. (tell your hw vendor)\n", reg_00.bits.ID);
 
1391			ioapics[ioapic_idx].mp_config.apicid = reg_00.bits.ID;
1392		}
1393
1394		/*
1395		 * Sanity check, is the ID really free? Every APIC in a
1396		 * system must have a unique ID or we get lots of nice
1397		 * 'stuck on smp_invalidate_needed IPI wait' messages.
1398		 */
1399		if (test_bit(mpc_ioapic_id(ioapic_idx), phys_id_present_map)) {
1400			pr_err(FW_BUG "IO-APIC#%d ID %d is already used!...\n",
1401			       ioapic_idx, mpc_ioapic_id(ioapic_idx));
1402			for (i = 0; i < broadcast_id; i++)
1403				if (!test_bit(i, phys_id_present_map))
 
1404					break;
1405			if (i >= broadcast_id)
1406				panic("Max APIC ID exceeded!\n");
1407			pr_err("... fixing up to %d. (tell your hw vendor)\n", i);
1408			set_bit(i, phys_id_present_map);
 
1409			ioapics[ioapic_idx].mp_config.apicid = i;
1410		} else {
1411			apic_pr_verbose("Setting %d in the phys_id_present_map\n",
 
 
 
 
1412					mpc_ioapic_id(ioapic_idx));
1413			set_bit(mpc_ioapic_id(ioapic_idx), phys_id_present_map);
1414		}
1415
1416		/*
1417		 * We need to adjust the IRQ routing table if the ID
1418		 * changed.
1419		 */
1420		if (old_id != mpc_ioapic_id(ioapic_idx)) {
1421			for (i = 0; i < mp_irq_entries; i++) {
1422				if (mp_irqs[i].dstapic == old_id)
1423					mp_irqs[i].dstapic = mpc_ioapic_id(ioapic_idx);
1424			}
1425		}
1426
1427		/*
1428		 * Update the ID register according to the right value from
1429		 * the MPC table if they are different.
1430		 */
1431		if (mpc_ioapic_id(ioapic_idx) == reg_00.bits.ID)
1432			continue;
1433
1434		apic_pr_verbose("...changing IO-APIC physical APIC ID to %d ...",
1435				mpc_ioapic_id(ioapic_idx));
 
1436
1437		reg_00.bits.ID = mpc_ioapic_id(ioapic_idx);
1438		scoped_guard (raw_spinlock_irqsave, &ioapic_lock) {
1439			io_apic_write(ioapic_idx, 0, reg_00.raw);
1440			reg_00.raw = io_apic_read(ioapic_idx, 0);
1441		}
1442		/* Sanity check */
 
 
 
 
 
1443		if (reg_00.bits.ID != mpc_ioapic_id(ioapic_idx))
1444			pr_cont("could not set ID!\n");
1445		else
1446			apic_pr_verbose(" ok.\n");
1447	}
1448}
1449
1450void __init setup_ioapic_ids_from_mpc(void)
1451{
1452
1453	if (acpi_ioapic)
1454		return;
1455	/*
1456	 * Don't check I/O APIC IDs for xAPIC systems.  They have
1457	 * no meaning without the serial APIC bus.
1458	 */
1459	if (!(boot_cpu_data.x86_vendor == X86_VENDOR_INTEL)
1460		|| APIC_XAPIC(boot_cpu_apic_version))
1461		return;
1462	setup_ioapic_ids_from_mpc_nocheck();
1463}
1464#endif
1465
1466int no_timer_check __initdata;
1467
1468static int __init notimercheck(char *s)
1469{
1470	no_timer_check = 1;
1471	return 1;
1472}
1473__setup("no_timer_check", notimercheck);
1474
1475static void __init delay_with_tsc(void)
1476{
1477	unsigned long long start, now;
1478	unsigned long end = jiffies + 4;
1479
1480	start = rdtsc();
1481
1482	/*
1483	 * We don't know the TSC frequency yet, but waiting for
1484	 * 40000000000/HZ TSC cycles is safe:
1485	 * 4 GHz == 10 jiffies
1486	 * 1 GHz == 40 jiffies
1487	 */
1488	do {
1489		rep_nop();
1490		now = rdtsc();
1491	} while ((now - start) < 40000000000ULL / HZ &&	time_before_eq(jiffies, end));
 
1492}
1493
1494static void __init delay_without_tsc(void)
1495{
1496	unsigned long end = jiffies + 4;
1497	int band = 1;
1498
1499	/*
1500	 * We don't know any frequency yet, but waiting for
1501	 * 40940000000/HZ cycles is safe:
1502	 * 4 GHz == 10 jiffies
1503	 * 1 GHz == 40 jiffies
1504	 * 1 << 1 + 1 << 2 +...+ 1 << 11 = 4094
1505	 */
1506	do {
1507		__delay(((1U << band++) * 10000000UL) / HZ);
1508	} while (band < 12 && time_before_eq(jiffies, end));
1509}
1510
1511/*
1512 * There is a nasty bug in some older SMP boards, their mptable lies
1513 * about the timer IRQ. We do the following to work around the situation:
1514 *
1515 *	- timer IRQ defaults to IO-APIC IRQ
1516 *	- if this function detects that timer IRQs are defunct, then we fall
1517 *	  back to ISA timer IRQs
1518 */
1519static int __init timer_irq_works(void)
1520{
1521	unsigned long t1 = jiffies;
 
1522
1523	if (no_timer_check)
1524		return 1;
1525
 
1526	local_irq_enable();
 
1527	if (boot_cpu_has(X86_FEATURE_TSC))
1528		delay_with_tsc();
1529	else
1530		delay_without_tsc();
1531
 
 
1532	/*
1533	 * Expect a few ticks at least, to be sure some possible
1534	 * glue logic does not lock up after one or two first
1535	 * ticks in a non-ExtINT mode.  Also the local APIC
1536	 * might have cached one ExtINT interrupt.  Finally, at
1537	 * least one tick may be lost due to delays.
1538	 */
1539
1540	local_irq_disable();
1541
1542	/* Did jiffies advance? */
1543	return time_after(jiffies, t1 + 4);
1544}
1545
1546/*
1547 * In the SMP+IOAPIC case it might happen that there are an unspecified
1548 * number of pending IRQ events unhandled. These cases are very rare,
1549 * so we 'resend' these IRQs via IPIs, to the same CPU. It's much
1550 * better to do it this way as thus we do not have to be aware of
1551 * 'pending' interrupts in the IRQ path, except at this point.
 
 
 
 
 
 
 
 
 
 
 
 
1552 *
1553 *
1554 * Edge triggered needs to resend any interrupt that was delayed but this
1555 * is now handled in the device independent code.
1556 *
1557 * Starting up a edge-triggered IO-APIC interrupt is nasty - we need to
1558 * make sure that we get the edge.  If it is already asserted for some
1559 * reason, we need return 1 to indicate that is was pending.
1560 *
1561 * This is not complete - we should be able to fake an edge even if it
1562 * isn't on the 8259A...
1563 */
1564static unsigned int startup_ioapic_irq(struct irq_data *data)
1565{
1566	int was_pending = 0, irq = data->irq;
 
1567
1568	guard(raw_spinlock_irqsave)(&ioapic_lock);
1569	if (irq < nr_legacy_irqs()) {
1570		legacy_pic->mask(irq);
1571		if (legacy_pic->irq_pending(irq))
1572			was_pending = 1;
1573	}
1574	__unmask_ioapic(data->chip_data);
 
 
1575	return was_pending;
1576}
1577
1578atomic_t irq_mis_count;
1579
1580#ifdef CONFIG_GENERIC_PENDING_IRQ
1581static bool io_apic_level_ack_pending(struct mp_chip_data *data)
1582{
1583	struct irq_pin_list *entry;
 
1584
1585	guard(raw_spinlock_irqsave)(&ioapic_lock);
1586	for_each_irq_pin(entry, data->irq_2_pin) {
1587		struct IO_APIC_route_entry e;
1588		int pin;
1589
1590		pin = entry->pin;
1591		e.w1 = io_apic_read(entry->apic, 0x10 + pin*2);
1592		/* Is the remote IRR bit set? */
1593		if (e.irr)
 
1594			return true;
 
1595	}
 
 
1596	return false;
1597}
1598
1599static inline bool ioapic_prepare_move(struct irq_data *data)
1600{
1601	/* If we are moving the IRQ we need to mask it */
1602	if (unlikely(irqd_is_setaffinity_pending(data))) {
1603		if (!irqd_irq_masked(data))
1604			mask_ioapic_irq(data);
1605		return true;
1606	}
1607	return false;
1608}
1609
1610static inline void ioapic_finish_move(struct irq_data *data, bool moveit)
1611{
1612	if (unlikely(moveit)) {
1613		/*
1614		 * Only migrate the irq if the ack has been received.
1615		 *
1616		 * On rare occasions the broadcast level triggered ack gets
1617		 * delayed going to ioapics, and if we reprogram the
1618		 * vector while Remote IRR is still set the irq will never
1619		 * fire again.
1620		 *
1621		 * To prevent this scenario we read the Remote IRR bit
1622		 * of the ioapic.  This has two effects.
1623		 * - On any sane system the read of the ioapic will
1624		 *   flush writes (and acks) going to the ioapic from
1625		 *   this cpu.
1626		 * - We get to see if the ACK has actually been delivered.
1627		 *
1628		 * Based on failed experiments of reprogramming the
1629		 * ioapic entry from outside of irq context starting
1630		 * with masking the ioapic entry and then polling until
1631		 * Remote IRR was clear before reprogramming the
1632		 * ioapic I don't trust the Remote IRR bit to be
1633		 * completely accurate.
1634		 *
1635		 * However there appears to be no other way to plug
1636		 * this race, so if the Remote IRR bit is not
1637		 * accurate and is causing problems then it is a hardware bug
1638		 * and you can go talk to the chipset vendor about it.
1639		 */
1640		if (!io_apic_level_ack_pending(data->chip_data))
1641			irq_move_masked_irq(data);
1642		/* If the IRQ is masked in the core, leave it: */
1643		if (!irqd_irq_masked(data))
1644			unmask_ioapic_irq(data);
1645	}
1646}
1647#else
1648static inline bool ioapic_prepare_move(struct irq_data *data)
1649{
1650	return false;
1651}
1652static inline void ioapic_finish_move(struct irq_data *data, bool moveit)
1653{
1654}
1655#endif
1656
1657static void ioapic_ack_level(struct irq_data *irq_data)
1658{
1659	struct irq_cfg *cfg = irqd_cfg(irq_data);
1660	unsigned long v;
1661	bool moveit;
1662	int i;
1663
1664	irq_complete_move(cfg);
1665	moveit = ioapic_prepare_move(irq_data);
1666
1667	/*
1668	 * It appears there is an erratum which affects at least version 0x11
1669	 * of I/O APIC (that's the 82093AA and cores integrated into various
1670	 * chipsets).  Under certain conditions a level-triggered interrupt is
1671	 * erroneously delivered as edge-triggered one but the respective IRR
1672	 * bit gets set nevertheless.  As a result the I/O unit expects an EOI
1673	 * message but it will never arrive and further interrupts are blocked
1674	 * from the source.  The exact reason is so far unknown, but the
1675	 * phenomenon was observed when two consecutive interrupt requests
1676	 * from a given source get delivered to the same CPU and the source is
1677	 * temporarily disabled in between.
1678	 *
1679	 * A workaround is to simulate an EOI message manually.  We achieve it
1680	 * by setting the trigger mode to edge and then to level when the edge
1681	 * trigger mode gets detected in the TMR of a local APIC for a
1682	 * level-triggered interrupt.  We mask the source for the time of the
1683	 * operation to prevent an edge-triggered interrupt escaping meanwhile.
1684	 * The idea is from Manfred Spraul.  --macro
1685	 *
1686	 * Also in the case when cpu goes offline, fixup_irqs() will forward
1687	 * any unhandled interrupt on the offlined cpu to the new cpu
1688	 * destination that is handling the corresponding interrupt. This
1689	 * interrupt forwarding is done via IPI's. Hence, in this case also
1690	 * level-triggered io-apic interrupt will be seen as an edge
1691	 * interrupt in the IRR. And we can't rely on the cpu's EOI
1692	 * to be broadcasted to the IO-APIC's which will clear the remoteIRR
1693	 * corresponding to the level-triggered interrupt. Hence on IO-APIC's
1694	 * supporting EOI register, we do an explicit EOI to clear the
1695	 * remote IRR and on IO-APIC's which don't have an EOI register,
1696	 * we use the above logic (mask+edge followed by unmask+level) from
1697	 * Manfred Spraul to clear the remote IRR.
1698	 */
1699	i = cfg->vector;
1700	v = apic_read(APIC_TMR + ((i & ~0x1f) >> 1));
1701
1702	/*
1703	 * We must acknowledge the irq before we move it or the acknowledge will
1704	 * not propagate properly.
1705	 */
1706	apic_eoi();
1707
1708	/*
1709	 * Tail end of clearing remote IRR bit (either by delivering the EOI
1710	 * message via io-apic EOI register write or simulating it using
1711	 * mask+edge followed by unmask+level logic) manually when the
1712	 * level triggered interrupt is seen as the edge triggered interrupt
1713	 * at the cpu.
1714	 */
1715	if (!(v & (1 << (i & 0x1f)))) {
1716		atomic_inc(&irq_mis_count);
1717		eoi_ioapic_pin(cfg->vector, irq_data->chip_data);
1718	}
1719
1720	ioapic_finish_move(irq_data, moveit);
1721}
1722
1723static void ioapic_ir_ack_level(struct irq_data *irq_data)
1724{
1725	struct mp_chip_data *data = irq_data->chip_data;
1726
1727	/*
1728	 * Intr-remapping uses pin number as the virtual vector
1729	 * in the RTE. Actual vector is programmed in
1730	 * intr-remapping table entry. Hence for the io-apic
1731	 * EOI we use the pin number.
1732	 */
1733	apic_ack_irq(irq_data);
1734	eoi_ioapic_pin(data->entry.vector, data);
1735}
1736
1737/*
1738 * The I/OAPIC is just a device for generating MSI messages from legacy
1739 * interrupt pins. Various fields of the RTE translate into bits of the
1740 * resulting MSI which had a historical meaning.
1741 *
1742 * With interrupt remapping, many of those bits have different meanings
1743 * in the underlying MSI, but the way that the I/OAPIC transforms them
1744 * from its RTE to the MSI message is the same. This function allows
1745 * the parent IRQ domain to compose the MSI message, then takes the
1746 * relevant bits to put them in the appropriate places in the RTE in
1747 * order to generate that message when the IRQ happens.
1748 *
1749 * The setup here relies on a preconfigured route entry (is_level,
1750 * active_low, masked) because the parent domain is merely composing the
1751 * generic message routing information which is used for the MSI.
1752 */
1753static void ioapic_setup_msg_from_msi(struct irq_data *irq_data,
1754				      struct IO_APIC_route_entry *entry)
1755{
1756	struct msi_msg msg;
1757
1758	/* Let the parent domain compose the MSI message */
1759	irq_chip_compose_msi_msg(irq_data, &msg);
1760
1761	/*
1762	 * - Real vector
1763	 * - DMAR/IR: 8bit subhandle (ioapic.pin)
1764	 * - AMD/IR:  8bit IRTE index
1765	 */
1766	entry->vector			= msg.arch_data.vector;
1767	/* Delivery mode (for DMAR/IR all 0) */
1768	entry->delivery_mode		= msg.arch_data.delivery_mode;
1769	/* Destination mode or DMAR/IR index bit 15 */
1770	entry->dest_mode_logical	= msg.arch_addr_lo.dest_mode_logical;
1771	/* DMAR/IR: 1, 0 for all other modes */
1772	entry->ir_format		= msg.arch_addr_lo.dmar_format;
1773	/*
1774	 * - DMAR/IR: index bit 0-14.
1775	 *
1776	 * - Virt: If the host supports x2apic without a virtualized IR
1777	 *	   unit then bit 0-6 of dmar_index_0_14 are providing bit
1778	 *	   8-14 of the destination id.
1779	 *
1780	 * All other modes have bit 0-6 of dmar_index_0_14 cleared and the
1781	 * topmost 8 bits are destination id bit 0-7 (entry::destid_0_7).
1782	 */
1783	entry->ir_index_0_14		= msg.arch_addr_lo.dmar_index_0_14;
1784}
1785
1786static void ioapic_configure_entry(struct irq_data *irqd)
1787{
1788	struct mp_chip_data *mpd = irqd->chip_data;
 
1789	struct irq_pin_list *entry;
1790
1791	ioapic_setup_msg_from_msi(irqd, &mpd->entry);
1792
 
 
 
 
 
 
 
1793	for_each_irq_pin(entry, mpd->irq_2_pin)
1794		__ioapic_write_entry(entry->apic, entry->pin, mpd->entry);
1795}
1796
1797static int ioapic_set_affinity(struct irq_data *irq_data, const struct cpumask *mask, bool force)
 
1798{
1799	struct irq_data *parent = irq_data->parent_data;
 
1800	int ret;
1801
1802	ret = parent->chip->irq_set_affinity(parent, mask, force);
1803
1804	guard(raw_spinlock_irqsave)(&ioapic_lock);
1805	if (ret >= 0 && ret != IRQ_SET_MASK_OK_DONE)
1806		ioapic_configure_entry(irq_data);
 
1807
1808	return ret;
1809}
1810
1811/*
1812 * Interrupt shutdown masks the ioapic pin, but the interrupt might already
1813 * be in flight, but not yet serviced by the target CPU. That means
1814 * __synchronize_hardirq() would return and claim that everything is calmed
1815 * down. So free_irq() would proceed and deactivate the interrupt and free
1816 * resources.
1817 *
1818 * Once the target CPU comes around to service it it will find a cleared
1819 * vector and complain. While the spurious interrupt is harmless, the full
1820 * release of resources might prevent the interrupt from being acknowledged
1821 * which keeps the hardware in a weird state.
1822 *
1823 * Verify that the corresponding Remote-IRR bits are clear.
1824 */
1825static int ioapic_irq_get_chip_state(struct irq_data *irqd, enum irqchip_irq_state which,
1826				     bool *state)
 
1827{
1828	struct mp_chip_data *mcd = irqd->chip_data;
1829	struct IO_APIC_route_entry rentry;
1830	struct irq_pin_list *p;
1831
1832	if (which != IRQCHIP_STATE_ACTIVE)
1833		return -EINVAL;
1834
1835	*state = false;
1836
1837	guard(raw_spinlock)(&ioapic_lock);
1838	for_each_irq_pin(p, mcd->irq_2_pin) {
1839		rentry = __ioapic_read_entry(p->apic, p->pin);
1840		/*
1841		 * The remote IRR is only valid in level trigger mode. It's
1842		 * meaning is undefined for edge triggered interrupts and
1843		 * irrelevant because the IO-APIC treats them as fire and
1844		 * forget.
1845		 */
1846		if (rentry.irr && rentry.is_level) {
1847			*state = true;
1848			break;
1849		}
1850	}
 
1851	return 0;
1852}
1853
1854static struct irq_chip ioapic_chip __read_mostly = {
1855	.name			= "IO-APIC",
1856	.irq_startup		= startup_ioapic_irq,
1857	.irq_mask		= mask_ioapic_irq,
1858	.irq_unmask		= unmask_ioapic_irq,
1859	.irq_ack		= irq_chip_ack_parent,
1860	.irq_eoi		= ioapic_ack_level,
1861	.irq_set_affinity	= ioapic_set_affinity,
1862	.irq_retrigger		= irq_chip_retrigger_hierarchy,
1863	.irq_get_irqchip_state	= ioapic_irq_get_chip_state,
1864	.flags			= IRQCHIP_SKIP_SET_WAKE |
1865				  IRQCHIP_AFFINITY_PRE_STARTUP,
1866};
1867
1868static struct irq_chip ioapic_ir_chip __read_mostly = {
1869	.name			= "IR-IO-APIC",
1870	.irq_startup		= startup_ioapic_irq,
1871	.irq_mask		= mask_ioapic_irq,
1872	.irq_unmask		= unmask_ioapic_irq,
1873	.irq_ack		= irq_chip_ack_parent,
1874	.irq_eoi		= ioapic_ir_ack_level,
1875	.irq_set_affinity	= ioapic_set_affinity,
1876	.irq_retrigger		= irq_chip_retrigger_hierarchy,
1877	.irq_get_irqchip_state	= ioapic_irq_get_chip_state,
1878	.flags			= IRQCHIP_SKIP_SET_WAKE |
1879				  IRQCHIP_AFFINITY_PRE_STARTUP,
1880};
1881
1882static inline void init_IO_APIC_traps(void)
1883{
1884	struct irq_cfg *cfg;
1885	unsigned int irq;
1886
1887	for_each_active_irq(irq) {
1888		cfg = irq_cfg(irq);
1889		if (IO_APIC_IRQ(irq) && cfg && !cfg->vector) {
1890			/*
1891			 * Hmm.. We don't have an entry for this, so
1892			 * default to an old-fashioned 8259 interrupt if we
1893			 * can. Otherwise set the dummy interrupt chip.
1894			 */
1895			if (irq < nr_legacy_irqs())
1896				legacy_pic->make_irq(irq);
1897			else
 
1898				irq_set_chip(irq, &no_irq_chip);
1899		}
1900	}
1901}
1902
1903/*
1904 * The local APIC irq-chip implementation:
1905 */
 
1906static void mask_lapic_irq(struct irq_data *data)
1907{
1908	unsigned long v = apic_read(APIC_LVT0);
1909
 
1910	apic_write(APIC_LVT0, v | APIC_LVT_MASKED);
1911}
1912
1913static void unmask_lapic_irq(struct irq_data *data)
1914{
1915	unsigned long v = apic_read(APIC_LVT0);
1916
 
1917	apic_write(APIC_LVT0, v & ~APIC_LVT_MASKED);
1918}
1919
1920static void ack_lapic_irq(struct irq_data *data)
1921{
1922	apic_eoi();
1923}
1924
1925static struct irq_chip lapic_chip __read_mostly = {
1926	.name		= "local-APIC",
1927	.irq_mask	= mask_lapic_irq,
1928	.irq_unmask	= unmask_lapic_irq,
1929	.irq_ack	= ack_lapic_irq,
1930};
1931
1932static void lapic_register_intr(int irq)
1933{
1934	irq_clear_status_flags(irq, IRQ_LEVEL);
1935	irq_set_chip_and_handler_name(irq, &lapic_chip, handle_edge_irq, "edge");
 
1936}
1937
1938/*
1939 * This looks a bit hackish but it's about the only one way of sending
1940 * a few INTA cycles to 8259As and any associated glue logic.  ICR does
1941 * not support the ExtINT mode, unfortunately.  We need to send these
1942 * cycles as some i82489DX-based boards have glue logic that keeps the
1943 * 8259A interrupt line asserted until INTA.  --macro
1944 */
1945static inline void __init unlock_ExtINT_logic(void)
1946{
1947	unsigned char save_control, save_freq_select;
1948	struct IO_APIC_route_entry entry0, entry1;
1949	int apic, pin, i;
1950	u32 apic_id;
 
1951
1952	pin  = find_isa_irq_pin(8, mp_INT);
1953	if (pin == -1) {
1954		WARN_ON_ONCE(1);
1955		return;
1956	}
1957	apic = find_isa_irq_apic(8, mp_INT);
1958	if (apic == -1) {
1959		WARN_ON_ONCE(1);
1960		return;
1961	}
1962
1963	entry0 = ioapic_read_entry(apic, pin);
1964	clear_IO_APIC_pin(apic, pin);
1965
1966	apic_id = read_apic_id();
1967	memset(&entry1, 0, sizeof(entry1));
1968
1969	entry1.dest_mode_logical	= true;
1970	entry1.masked			= false;
1971	entry1.destid_0_7		= apic_id & 0xFF;
1972	entry1.virt_destid_8_14		= apic_id >> 8;
1973	entry1.delivery_mode		= APIC_DELIVERY_MODE_EXTINT;
1974	entry1.active_low		= entry0.active_low;
1975	entry1.is_level			= false;
1976	entry1.vector = 0;
1977
1978	ioapic_write_entry(apic, pin, entry1);
1979
1980	save_control = CMOS_READ(RTC_CONTROL);
1981	save_freq_select = CMOS_READ(RTC_FREQ_SELECT);
1982	CMOS_WRITE((save_freq_select & ~RTC_RATE_SELECT) | 0x6,
1983		   RTC_FREQ_SELECT);
1984	CMOS_WRITE(save_control | RTC_PIE, RTC_CONTROL);
1985
1986	i = 100;
1987	while (i-- > 0) {
1988		mdelay(10);
1989		if ((CMOS_READ(RTC_INTR_FLAGS) & RTC_PF) == RTC_PF)
1990			i -= 10;
1991	}
1992
1993	CMOS_WRITE(save_control, RTC_CONTROL);
1994	CMOS_WRITE(save_freq_select, RTC_FREQ_SELECT);
1995	clear_IO_APIC_pin(apic, pin);
1996
1997	ioapic_write_entry(apic, pin, entry0);
1998}
1999
2000static int disable_timer_pin_1 __initdata;
2001/* Actually the next is obsolete, but keep it for paranoid reasons -AK */
2002static int __init disable_timer_pin_setup(char *arg)
2003{
2004	disable_timer_pin_1 = 1;
2005	return 0;
2006}
2007early_param("disable_timer_pin_1", disable_timer_pin_setup);
2008
2009static int __init mp_alloc_timer_irq(int ioapic, int pin)
2010{
2011	struct irq_domain *domain = mp_ioapic_irqdomain(ioapic);
2012	int irq = -1;
 
2013
2014	if (domain) {
2015		struct irq_alloc_info info;
2016
2017		ioapic_set_alloc_attr(&info, NUMA_NO_NODE, 0, 0);
2018		info.devid = mpc_ioapic_id(ioapic);
2019		info.ioapic.pin = pin;
2020		guard(mutex)(&ioapic_mutex);
2021		irq = alloc_isa_irq_from_domain(domain, 0, ioapic, pin, &info);
 
2022	}
2023
2024	return irq;
2025}
2026
2027static void __init replace_pin_at_irq_node(struct mp_chip_data *data, int node,
2028					   int oldapic, int oldpin,
2029					   int newapic, int newpin)
2030{
2031	struct irq_pin_list *entry;
2032
2033	for_each_irq_pin(entry, data->irq_2_pin) {
2034		if (entry->apic == oldapic && entry->pin == oldpin) {
2035			entry->apic = newapic;
2036			entry->pin = newpin;
2037			return;
2038		}
2039	}
2040
2041	/* Old apic/pin didn't exist, so just add a new one */
2042	add_pin_to_irq_node(data, node, newapic, newpin);
2043}
2044
2045/*
2046 * This code may look a bit paranoid, but it's supposed to cooperate with
2047 * a wide range of boards and BIOS bugs.  Fortunately only the timer IRQ
2048 * is so screwy.  Thanks to Brian Perkins for testing/hacking this beast
2049 * fanatically on his truly buggy board.
 
 
2050 */
2051static inline void __init check_timer(void)
2052{
2053	struct irq_data *irq_data = irq_get_irq_data(0);
2054	struct mp_chip_data *data = irq_data->chip_data;
2055	struct irq_cfg *cfg = irqd_cfg(irq_data);
2056	int node = cpu_to_node(0);
2057	int apic1, pin1, apic2, pin2;
 
2058	int no_pin1 = 0;
2059
2060	if (!global_clock_event)
2061		return;
2062
2063	local_irq_disable();
2064
2065	/*
2066	 * get/set the timer IRQ vector:
2067	 */
2068	legacy_pic->mask(0);
2069
2070	/*
2071	 * As IRQ0 is to be enabled in the 8259A, the virtual
2072	 * wire has to be disabled in the local APIC.  Also
2073	 * timer interrupts need to be acknowledged manually in
2074	 * the 8259A for the i82489DX when using the NMI
2075	 * watchdog as that APIC treats NMIs as level-triggered.
2076	 * The AEOI mode will finish them in the 8259A
2077	 * automatically.
2078	 */
2079	apic_write(APIC_LVT0, APIC_LVT_MASKED | APIC_DM_EXTINT);
2080	legacy_pic->init(1);
2081
2082	pin1  = find_isa_irq_pin(0, mp_INT);
2083	apic1 = find_isa_irq_apic(0, mp_INT);
2084	pin2  = ioapic_i8259.pin;
2085	apic2 = ioapic_i8259.apic;
2086
2087	pr_info("..TIMER: vector=0x%02X apic1=%d pin1=%d apic2=%d pin2=%d\n",
2088		cfg->vector, apic1, pin1, apic2, pin2);
 
2089
2090	/*
2091	 * Some BIOS writers are clueless and report the ExtINTA
2092	 * I/O APIC input from the cascaded 8259A as the timer
2093	 * interrupt input.  So just in case, if only one pin
2094	 * was found above, try it both directly and through the
2095	 * 8259A.
2096	 */
2097	if (pin1 == -1) {
2098		panic_if_irq_remap(FW_BUG "Timer not connected to IO-APIC");
2099		pin1 = pin2;
2100		apic1 = apic2;
2101		no_pin1 = 1;
2102	} else if (pin2 == -1) {
2103		pin2 = pin1;
2104		apic2 = apic1;
2105	}
2106
2107	if (pin1 != -1) {
2108		/* Ok, does IRQ0 through the IOAPIC work? */
2109		if (no_pin1) {
2110			mp_alloc_timer_irq(apic1, pin1);
2111		} else {
2112			/*
2113			 * for edge trigger, it's already unmasked,
2114			 * so only need to unmask if it is level-trigger
2115			 * do we really have level trigger timer?
2116			 */
2117			int idx = find_irq_entry(apic1, pin1, mp_INT);
2118
2119			if (idx != -1 && irq_is_level(idx))
2120				unmask_ioapic_irq(irq_get_irq_data(0));
2121		}
2122		irq_domain_deactivate_irq(irq_data);
2123		irq_domain_activate_irq(irq_data, false);
2124		if (timer_irq_works()) {
2125			if (disable_timer_pin_1 > 0)
2126				clear_IO_APIC_pin(0, pin1);
2127			goto out;
2128		}
2129		panic_if_irq_remap("timer doesn't work through Interrupt-remapped IO-APIC");
 
2130		clear_IO_APIC_pin(apic1, pin1);
2131		if (!no_pin1)
2132			pr_err("..MP-BIOS bug: 8254 timer not connected to IO-APIC\n");
 
2133
2134		pr_info("...trying to set up timer (IRQ0) through the 8259A ...\n");
2135		pr_info("..... (found apic %d pin %d) ...\n", apic2, pin2);
 
 
2136		/*
2137		 * legacy devices should be connected to IO APIC #0
2138		 */
2139		replace_pin_at_irq_node(data, node, apic1, pin1, apic2, pin2);
2140		irq_domain_deactivate_irq(irq_data);
2141		irq_domain_activate_irq(irq_data, false);
2142		legacy_pic->unmask(0);
2143		if (timer_irq_works()) {
2144			pr_info("....... works.\n");
2145			goto out;
2146		}
2147		/*
2148		 * Cleanup, just in case ...
2149		 */
 
2150		legacy_pic->mask(0);
2151		clear_IO_APIC_pin(apic2, pin2);
2152		pr_info("....... failed.\n");
2153	}
2154
2155	pr_info("...trying to set up timer as Virtual Wire IRQ...\n");
 
2156
2157	lapic_register_intr(0);
2158	apic_write(APIC_LVT0, APIC_DM_FIXED | cfg->vector);	/* Fixed mode */
2159	legacy_pic->unmask(0);
2160
2161	if (timer_irq_works()) {
2162		pr_info("..... works.\n");
2163		goto out;
2164	}
 
2165	legacy_pic->mask(0);
2166	apic_write(APIC_LVT0, APIC_LVT_MASKED | APIC_DM_FIXED | cfg->vector);
2167	pr_info("..... failed.\n");
2168
2169	pr_info("...trying to set up timer as ExtINT IRQ...\n");
 
2170
2171	legacy_pic->init(0);
2172	legacy_pic->make_irq(0);
2173	apic_write(APIC_LVT0, APIC_DM_EXTINT);
2174	legacy_pic->unmask(0);
2175
2176	unlock_ExtINT_logic();
2177
2178	if (timer_irq_works()) {
2179		pr_info("..... works.\n");
2180		goto out;
2181	}
2182
2183	pr_info("..... failed :\n");
2184	if (apic_is_x2apic_enabled()) {
2185		pr_info("Perhaps problem with the pre-enabled x2apic mode\n"
2186			"Try booting with x2apic and interrupt-remapping disabled in the bios.\n");
2187	}
2188	panic("IO-APIC + timer doesn't work!  Boot with apic=debug and send a "
2189		"report.  Then try booting with the 'noapic' option.\n");
2190out:
2191	local_irq_enable();
2192}
2193
2194/*
2195 * Traditionally ISA IRQ2 is the cascade IRQ, and is not available
2196 * to devices.  However there may be an I/O APIC pin available for
2197 * this interrupt regardless.  The pin may be left unconnected, but
2198 * typically it will be reused as an ExtINT cascade interrupt for
2199 * the master 8259A.  In the MPS case such a pin will normally be
2200 * reported as an ExtINT interrupt in the MP table.  With ACPI
2201 * there is no provision for ExtINT interrupts, and in the absence
2202 * of an override it would be treated as an ordinary ISA I/O APIC
2203 * interrupt, that is edge-triggered and unmasked by default.  We
2204 * used to do this, but it caused problems on some systems because
2205 * of the NMI watchdog and sometimes IRQ0 of the 8254 timer using
2206 * the same ExtINT cascade interrupt to drive the local APIC of the
2207 * bootstrap processor.  Therefore we refrain from routing IRQ2 to
2208 * the I/O APIC in all cases now.  No actual device should request
2209 * it anyway.  --macro
2210 */
2211#define PIC_IRQS	(1UL << PIC_CASCADE_IR)
2212
2213static int mp_irqdomain_create(int ioapic)
2214{
2215	struct mp_ioapic_gsi *gsi_cfg = mp_ioapic_gsi_routing(ioapic);
 
2216	int hwirqs = mp_ioapic_pin_count(ioapic);
2217	struct ioapic *ip = &ioapics[ioapic];
2218	struct ioapic_domain_cfg *cfg = &ip->irqdomain_cfg;
2219	struct irq_domain *parent;
2220	struct fwnode_handle *fn;
2221	struct irq_fwspec fwspec;
2222
2223	if (cfg->type == IOAPIC_DOMAIN_INVALID)
2224		return 0;
2225
 
 
 
 
 
 
 
 
 
2226	/* Handle device tree enumerated APICs proper */
2227	if (cfg->dev) {
2228		fn = of_node_to_fwnode(cfg->dev);
2229	} else {
2230		fn = irq_domain_alloc_named_id_fwnode("IO-APIC", mpc_ioapic_id(ioapic));
2231		if (!fn)
2232			return -ENOMEM;
2233	}
2234
2235	fwspec.fwnode = fn;
2236	fwspec.param_count = 1;
2237	fwspec.param[0] = mpc_ioapic_id(ioapic);
2238
2239	parent = irq_find_matching_fwspec(&fwspec, DOMAIN_BUS_GENERIC_MSI);
2240	if (!parent) {
2241		if (!cfg->dev)
2242			irq_domain_free_fwnode(fn);
2243		return -ENODEV;
2244	}
2245
2246	ip->irqdomain = irq_domain_create_hierarchy(parent, 0, hwirqs, fn, cfg->ops,
2247						    (void *)(long)ioapic);
2248	if (!ip->irqdomain) {
2249		/* Release fw handle if it was allocated above */
2250		if (!cfg->dev)
2251			irq_domain_free_fwnode(fn);
2252		return -ENOMEM;
2253	}
2254
2255	if (cfg->type == IOAPIC_DOMAIN_LEGACY || cfg->type == IOAPIC_DOMAIN_STRICT)
2256		ioapic_dynirq_base = max(ioapic_dynirq_base, gsi_cfg->gsi_end + 1);
 
 
 
 
2257
2258	return 0;
2259}
2260
2261static void ioapic_destroy_irqdomain(int idx)
2262{
2263	struct ioapic_domain_cfg *cfg = &ioapics[idx].irqdomain_cfg;
2264	struct fwnode_handle *fn = ioapics[idx].irqdomain->fwnode;
2265
2266	if (ioapics[idx].irqdomain) {
2267		irq_domain_remove(ioapics[idx].irqdomain);
2268		if (!cfg->dev)
2269			irq_domain_free_fwnode(fn);
2270		ioapics[idx].irqdomain = NULL;
2271	}
2272}
2273
2274void __init setup_IO_APIC(void)
2275{
2276	int ioapic;
2277
2278	if (ioapic_is_disabled || !nr_ioapics)
2279		return;
2280
2281	io_apic_irqs = nr_legacy_irqs() ? ~PIC_IRQS : ~0UL;
2282
2283	apic_pr_verbose("ENABLING IO-APIC IRQs\n");
2284	for_each_ioapic(ioapic)
2285		BUG_ON(mp_irqdomain_create(ioapic));
2286
2287	/* Set up IO-APIC IRQ routing. */
 
 
2288	x86_init.mpparse.setup_ioapic_ids();
2289
2290	sync_Arb_IDs();
2291	setup_IO_APIC_irqs();
2292	init_IO_APIC_traps();
2293	if (nr_legacy_irqs())
2294		check_timer();
2295
2296	ioapic_initialized = 1;
2297}
2298
2299static void resume_ioapic_id(int ioapic_idx)
2300{
 
2301	union IO_APIC_reg_00 reg_00;
2302
2303	guard(raw_spinlock_irqsave)(&ioapic_lock);
2304	reg_00.raw = io_apic_read(ioapic_idx, 0);
2305	if (reg_00.bits.ID != mpc_ioapic_id(ioapic_idx)) {
2306		reg_00.bits.ID = mpc_ioapic_id(ioapic_idx);
2307		io_apic_write(ioapic_idx, 0, reg_00.raw);
2308	}
 
2309}
2310
2311static void ioapic_resume(void)
2312{
2313	int ioapic_idx;
2314
2315	for_each_ioapic_reverse(ioapic_idx)
2316		resume_ioapic_id(ioapic_idx);
2317
2318	restore_ioapic_entries();
2319}
2320
2321static struct syscore_ops ioapic_syscore_ops = {
2322	.suspend	= save_ioapic_entries,
2323	.resume		= ioapic_resume,
2324};
2325
2326static int __init ioapic_init_ops(void)
2327{
2328	register_syscore_ops(&ioapic_syscore_ops);
2329
2330	return 0;
2331}
2332
2333device_initcall(ioapic_init_ops);
2334
2335static int io_apic_get_redir_entries(int ioapic)
2336{
2337	union IO_APIC_reg_01	reg_01;
 
2338
2339	guard(raw_spinlock_irqsave)(&ioapic_lock);
2340	reg_01.raw = io_apic_read(ioapic, 1);
 
2341
2342	/*
2343	 * The register returns the maximum index redir index supported,
2344	 * which is one less than the total number of redir entries.
2345	 */
2346	return reg_01.bits.entries + 1;
2347}
2348
2349unsigned int arch_dynirq_lower_bound(unsigned int from)
2350{
2351	unsigned int ret;
2352
2353	/*
2354	 * dmar_alloc_hwirq() may be called before setup_IO_APIC(), so use
2355	 * gsi_top if ioapic_dynirq_base hasn't been initialized yet.
2356	 */
2357	ret = ioapic_dynirq_base ? : gsi_top;
2358
2359	/*
2360	 * For DT enabled machines ioapic_dynirq_base is irrelevant and
2361	 * always 0. gsi_top can be 0 if there is no IO/APIC registered.
2362	 * 0 is an invalid interrupt number for dynamic allocations. Return
2363	 * @from instead.
2364	 */
2365	return ret ? : from;
2366}
2367
2368#ifdef CONFIG_X86_32
2369static int io_apic_get_unique_id(int ioapic, int apic_id)
2370{
2371	static DECLARE_BITMAP(apic_id_map, MAX_LOCAL_APIC);
2372	const u32 broadcast_id = 0xF;
2373	union IO_APIC_reg_00 reg_00;
 
 
 
2374	int i = 0;
2375
2376	/* Initialize the ID map */
2377	if (bitmap_empty(apic_id_map, MAX_LOCAL_APIC))
2378		copy_phys_cpu_present_map(apic_id_map);
 
 
 
 
 
 
 
 
2379
2380	scoped_guard (raw_spinlock_irqsave, &ioapic_lock)
2381		reg_00.raw = io_apic_read(ioapic, 0);
 
2382
2383	if (apic_id >= broadcast_id) {
2384		pr_warn("IOAPIC[%d]: Invalid apic_id %d, trying %d\n",
2385			ioapic, apic_id, reg_00.bits.ID);
2386		apic_id = reg_00.bits.ID;
2387	}
2388
2389	/* Every APIC in a system must have a unique ID */
2390	if (test_bit(apic_id, apic_id_map)) {
2391		for (i = 0; i < broadcast_id; i++) {
2392			if (!test_bit(i, apic_id_map))
 
 
 
 
2393				break;
2394		}
2395
2396		if (i == broadcast_id)
2397			panic("Max apic_id exceeded!\n");
2398
2399		pr_warn("IOAPIC[%d]: apic_id %d already used, trying %d\n", ioapic, apic_id, i);
 
 
2400		apic_id = i;
2401	}
2402
2403	set_bit(apic_id, apic_id_map);
 
2404
2405	if (reg_00.bits.ID != apic_id) {
2406		reg_00.bits.ID = apic_id;
2407
2408		scoped_guard (raw_spinlock_irqsave, &ioapic_lock) {
2409			io_apic_write(ioapic, 0, reg_00.raw);
2410			reg_00.raw = io_apic_read(ioapic, 0);
2411		}
2412
2413		/* Sanity check */
2414		if (reg_00.bits.ID != apic_id) {
2415			pr_err("IOAPIC[%d]: Unable to change apic_id!\n", ioapic);
 
2416			return -1;
2417		}
2418	}
2419
2420	apic_pr_verbose("IOAPIC[%d]: Assigned apic_id %d\n", ioapic, apic_id);
 
2421
2422	return apic_id;
2423}
2424
2425static u8 io_apic_unique_id(int idx, u8 id)
2426{
2427	if ((boot_cpu_data.x86_vendor == X86_VENDOR_INTEL) && !APIC_XAPIC(boot_cpu_apic_version))
 
2428		return io_apic_get_unique_id(idx, id);
2429	return id;
 
2430}
2431#else
2432static u8 io_apic_unique_id(int idx, u8 id)
2433{
2434	union IO_APIC_reg_00 reg_00;
2435	DECLARE_BITMAP(used, 256);
 
2436	u8 new_id;
2437	int i;
2438
2439	bitmap_zero(used, 256);
2440	for_each_ioapic(i)
2441		__set_bit(mpc_ioapic_id(i), used);
2442
2443	/* Hand out the requested id if available */
2444	if (!test_bit(id, used))
2445		return id;
2446
2447	/*
2448	 * Read the current id from the ioapic and keep it if
2449	 * available.
2450	 */
2451	scoped_guard (raw_spinlock_irqsave, &ioapic_lock)
2452		reg_00.raw = io_apic_read(idx, 0);
2453
2454	new_id = reg_00.bits.ID;
2455	if (!test_bit(new_id, used)) {
2456		apic_pr_verbose("IOAPIC[%d]: Using reg apic_id %d instead of %d\n",
2457				idx, new_id, id);
 
2458		return new_id;
2459	}
2460
2461	/* Get the next free id and write it to the ioapic. */
 
 
2462	new_id = find_first_zero_bit(used, 256);
2463	reg_00.bits.ID = new_id;
2464	scoped_guard (raw_spinlock_irqsave, &ioapic_lock) {
2465		io_apic_write(idx, 0, reg_00.raw);
2466		reg_00.raw = io_apic_read(idx, 0);
2467	}
2468	/* Sanity check */
2469	BUG_ON(reg_00.bits.ID != new_id);
2470
2471	return new_id;
2472}
2473#endif
2474
2475static int io_apic_get_version(int ioapic)
2476{
2477	union IO_APIC_reg_01 reg_01;
 
2478
2479	guard(raw_spinlock_irqsave)(&ioapic_lock);
2480	reg_01.raw = io_apic_read(ioapic, 1);
 
2481
2482	return reg_01.bits.version;
2483}
2484
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2485/*
2486 * This function updates target affinity of IOAPIC interrupts to include
2487 * the CPUs which came online during SMP bringup.
2488 */
2489#define IOAPIC_RESOURCE_NAME_SIZE 11
2490
2491static struct resource *ioapic_resources;
2492
2493static struct resource * __init ioapic_setup_resources(void)
2494{
2495	struct resource *res;
2496	unsigned long n;
 
2497	char *mem;
2498	int i;
2499
2500	if (nr_ioapics == 0)
2501		return NULL;
2502
2503	n = IOAPIC_RESOURCE_NAME_SIZE + sizeof(struct resource);
2504	n *= nr_ioapics;
2505
2506	mem = memblock_alloc(n, SMP_CACHE_BYTES);
2507	if (!mem)
2508		panic("%s: Failed to allocate %lu bytes\n", __func__, n);
2509	res = (void *)mem;
2510
2511	mem += sizeof(struct resource) * nr_ioapics;
2512
2513	for_each_ioapic(i) {
2514		res[i].name = mem;
2515		res[i].flags = IORESOURCE_MEM | IORESOURCE_BUSY;
2516		snprintf(mem, IOAPIC_RESOURCE_NAME_SIZE, "IOAPIC %u", i);
2517		mem += IOAPIC_RESOURCE_NAME_SIZE;
2518		ioapics[i].iomem_res = &res[i];
2519	}
2520
2521	ioapic_resources = res;
2522
2523	return res;
2524}
2525
2526static void io_apic_set_fixmap(enum fixed_addresses idx, phys_addr_t phys)
2527{
2528	pgprot_t flags = FIXMAP_PAGE_NOCACHE;
2529
2530	/*
2531	 * Ensure fixmaps for IO-APIC MMIO respect memory encryption pgprot
2532	 * bits, just like normal ioremap():
2533	 */
2534	if (cc_platform_has(CC_ATTR_GUEST_MEM_ENCRYPT)) {
2535		if (x86_platform.hyper.is_private_mmio(phys))
2536			flags = pgprot_encrypted(flags);
2537		else
2538			flags = pgprot_decrypted(flags);
2539	}
2540
2541	__set_fixmap(idx, phys, flags);
2542}
2543
2544void __init io_apic_init_mappings(void)
2545{
2546	unsigned long ioapic_phys, idx = FIX_IO_APIC_BASE_0;
2547	struct resource *ioapic_res;
2548	int i;
2549
2550	ioapic_res = ioapic_setup_resources();
2551	for_each_ioapic(i) {
2552		if (smp_found_config) {
2553			ioapic_phys = mpc_ioapic_addr(i);
2554#ifdef CONFIG_X86_32
2555			if (!ioapic_phys) {
2556				pr_err("WARNING: bogus zero IO-APIC address found in MPTABLE, "
 
 
2557				       "disabling IO/APIC support!\n");
2558				smp_found_config = 0;
2559				ioapic_is_disabled = true;
2560				goto fake_ioapic_page;
2561			}
2562#endif
2563		} else {
2564#ifdef CONFIG_X86_32
2565fake_ioapic_page:
2566#endif
2567			ioapic_phys = (unsigned long)memblock_alloc(PAGE_SIZE,
2568								    PAGE_SIZE);
2569			if (!ioapic_phys)
2570				panic("%s: Failed to allocate %lu bytes align=0x%lx\n",
2571				      __func__, PAGE_SIZE, PAGE_SIZE);
2572			ioapic_phys = __pa(ioapic_phys);
2573		}
2574		io_apic_set_fixmap(idx, ioapic_phys);
2575		apic_pr_verbose("mapped IOAPIC to %08lx (%08lx)\n",
2576				__fix_to_virt(idx) + (ioapic_phys & ~PAGE_MASK), ioapic_phys);
 
2577		idx++;
2578
2579		ioapic_res->start = ioapic_phys;
2580		ioapic_res->end = ioapic_phys + IO_APIC_SLOT_SIZE - 1;
2581		ioapic_res++;
2582	}
2583}
2584
2585void __init ioapic_insert_resources(void)
2586{
2587	struct resource *r = ioapic_resources;
2588	int i;
 
2589
2590	if (!r) {
2591		if (nr_ioapics > 0)
2592			pr_err("IO APIC resources couldn't be allocated.\n");
 
2593		return;
2594	}
2595
2596	for_each_ioapic(i) {
2597		insert_resource(&iomem_resource, r);
2598		r++;
2599	}
2600}
2601
2602int mp_find_ioapic(u32 gsi)
2603{
2604	int i;
2605
2606	if (nr_ioapics == 0)
2607		return -1;
2608
2609	/* Find the IOAPIC that manages this GSI. */
2610	for_each_ioapic(i) {
2611		struct mp_ioapic_gsi *gsi_cfg = mp_ioapic_gsi_routing(i);
2612
2613		if (gsi >= gsi_cfg->gsi_base && gsi <= gsi_cfg->gsi_end)
2614			return i;
2615	}
2616
2617	pr_err("ERROR: Unable to locate IOAPIC for GSI %d\n", gsi);
2618	return -1;
2619}
2620
2621int mp_find_ioapic_pin(int ioapic, u32 gsi)
2622{
2623	struct mp_ioapic_gsi *gsi_cfg;
2624
2625	if (WARN_ON(ioapic < 0))
2626		return -1;
2627
2628	gsi_cfg = mp_ioapic_gsi_routing(ioapic);
2629	if (WARN_ON(gsi > gsi_cfg->gsi_end))
2630		return -1;
2631
2632	return gsi - gsi_cfg->gsi_base;
2633}
2634
2635static int bad_ioapic_register(int idx)
2636{
2637	union IO_APIC_reg_00 reg_00;
2638	union IO_APIC_reg_01 reg_01;
2639	union IO_APIC_reg_02 reg_02;
2640
2641	reg_00.raw = io_apic_read(idx, 0);
2642	reg_01.raw = io_apic_read(idx, 1);
2643	reg_02.raw = io_apic_read(idx, 2);
2644
2645	if (reg_00.raw == -1 && reg_01.raw == -1 && reg_02.raw == -1) {
2646		pr_warn("I/O APIC 0x%x registers return all ones, skipping!\n",
2647			mpc_ioapic_addr(idx));
2648		return 1;
2649	}
2650
2651	return 0;
2652}
2653
2654static int find_free_ioapic_entry(void)
2655{
2656	for (int idx = 0; idx < MAX_IO_APICS; idx++) {
 
 
2657		if (ioapics[idx].nr_registers == 0)
2658			return idx;
2659	}
2660	return MAX_IO_APICS;
2661}
2662
2663/**
2664 * mp_register_ioapic - Register an IOAPIC device
2665 * @id:		hardware IOAPIC ID
2666 * @address:	physical address of IOAPIC register area
2667 * @gsi_base:	base of GSI associated with the IOAPIC
2668 * @cfg:	configuration information for the IOAPIC
2669 */
2670int mp_register_ioapic(int id, u32 address, u32 gsi_base, struct ioapic_domain_cfg *cfg)
 
2671{
2672	bool hotplug = !!ioapic_initialized;
2673	struct mp_ioapic_gsi *gsi_cfg;
2674	int idx, ioapic, entries;
2675	u32 gsi_end;
2676
2677	if (!address) {
2678		pr_warn("Bogus (zero) I/O APIC address found, skipping!\n");
2679		return -EINVAL;
2680	}
2681
2682	for_each_ioapic(ioapic) {
2683		if (ioapics[ioapic].mp_config.apicaddr == address) {
2684			pr_warn("address 0x%x conflicts with IOAPIC%d\n", address, ioapic);
 
2685			return -EEXIST;
2686		}
2687	}
2688
2689	idx = find_free_ioapic_entry();
2690	if (idx >= MAX_IO_APICS) {
2691		pr_warn("Max # of I/O APICs (%d) exceeded (found %d), skipping\n",
2692			MAX_IO_APICS, idx);
2693		return -ENOSPC;
2694	}
2695
2696	ioapics[idx].mp_config.type = MP_IOAPIC;
2697	ioapics[idx].mp_config.flags = MPC_APIC_USABLE;
2698	ioapics[idx].mp_config.apicaddr = address;
2699
2700	io_apic_set_fixmap(FIX_IO_APIC_BASE_0 + idx, address);
2701	if (bad_ioapic_register(idx)) {
2702		clear_fixmap(FIX_IO_APIC_BASE_0 + idx);
2703		return -ENODEV;
2704	}
2705
2706	ioapics[idx].mp_config.apicid = io_apic_unique_id(idx, id);
2707	ioapics[idx].mp_config.apicver = io_apic_get_version(idx);
2708
2709	/*
2710	 * Build basic GSI lookup table to facilitate gsi->io_apic lookups
2711	 * and to prevent reprogramming of IOAPIC pins (PCI GSIs).
2712	 */
2713	entries = io_apic_get_redir_entries(idx);
2714	gsi_end = gsi_base + entries - 1;
2715	for_each_ioapic(ioapic) {
2716		gsi_cfg = mp_ioapic_gsi_routing(ioapic);
2717		if ((gsi_base >= gsi_cfg->gsi_base &&
2718		     gsi_base <= gsi_cfg->gsi_end) ||
2719		    (gsi_end >= gsi_cfg->gsi_base &&
2720		     gsi_end <= gsi_cfg->gsi_end)) {
2721			pr_warn("GSI range [%u-%u] for new IOAPIC conflicts with GSI[%u-%u]\n",
2722				gsi_base, gsi_end, gsi_cfg->gsi_base, gsi_cfg->gsi_end);
 
2723			clear_fixmap(FIX_IO_APIC_BASE_0 + idx);
2724			return -ENOSPC;
2725		}
2726	}
2727	gsi_cfg = mp_ioapic_gsi_routing(idx);
2728	gsi_cfg->gsi_base = gsi_base;
2729	gsi_cfg->gsi_end = gsi_end;
2730
2731	ioapics[idx].irqdomain = NULL;
2732	ioapics[idx].irqdomain_cfg = *cfg;
2733
2734	/*
2735	 * If mp_register_ioapic() is called during early boot stage when
2736	 * walking ACPI/DT tables, it's too early to create irqdomain,
2737	 * we are still using bootmem allocator. So delay it to setup_IO_APIC().
2738	 */
2739	if (hotplug) {
2740		if (mp_irqdomain_create(idx)) {
2741			clear_fixmap(FIX_IO_APIC_BASE_0 + idx);
2742			return -ENOMEM;
2743		}
2744		alloc_ioapic_saved_registers(idx);
2745	}
2746
2747	if (gsi_cfg->gsi_end >= gsi_top)
2748		gsi_top = gsi_cfg->gsi_end + 1;
2749	if (nr_ioapics <= idx)
2750		nr_ioapics = idx + 1;
2751
2752	/* Set nr_registers to mark entry present */
2753	ioapics[idx].nr_registers = entries;
2754
2755	pr_info("IOAPIC[%d]: apic_id %d, version %d, address 0x%x, GSI %d-%d\n",
2756		idx, mpc_ioapic_id(idx), mpc_ioapic_ver(idx), mpc_ioapic_addr(idx),
 
2757		gsi_cfg->gsi_base, gsi_cfg->gsi_end);
2758
2759	return 0;
2760}
2761
2762int mp_unregister_ioapic(u32 gsi_base)
2763{
2764	int ioapic, pin;
2765	int found = 0;
2766
2767	for_each_ioapic(ioapic) {
2768		if (ioapics[ioapic].gsi_config.gsi_base == gsi_base) {
2769			found = 1;
2770			break;
2771		}
2772	}
2773
2774	if (!found) {
2775		pr_warn("can't find IOAPIC for GSI %d\n", gsi_base);
2776		return -ENODEV;
2777	}
2778
2779	for_each_pin(ioapic, pin) {
2780		u32 gsi = mp_pin_to_gsi(ioapic, pin);
2781		int irq = mp_map_gsi_to_irq(gsi, 0, NULL);
2782		struct mp_chip_data *data;
2783
2784		if (irq >= 0) {
2785			data = irq_get_chip_data(irq);
2786			if (data && data->count) {
2787				pr_warn("pin%d on IOAPIC%d is still in use.\n",	pin, ioapic);
 
2788				return -EBUSY;
2789			}
2790		}
2791	}
2792
2793	/* Mark entry not present */
2794	ioapics[ioapic].nr_registers  = 0;
2795	ioapic_destroy_irqdomain(ioapic);
2796	free_ioapic_saved_registers(ioapic);
2797	if (ioapics[ioapic].iomem_res)
2798		release_resource(ioapics[ioapic].iomem_res);
2799	clear_fixmap(FIX_IO_APIC_BASE_0 + ioapic);
2800	memset(&ioapics[ioapic], 0, sizeof(ioapics[ioapic]));
2801
2802	return 0;
2803}
2804
2805int mp_ioapic_registered(u32 gsi_base)
2806{
2807	int ioapic;
2808
2809	for_each_ioapic(ioapic)
2810		if (ioapics[ioapic].gsi_config.gsi_base == gsi_base)
2811			return 1;
2812
2813	return 0;
2814}
2815
2816static void mp_irqdomain_get_attr(u32 gsi, struct mp_chip_data *data,
2817				  struct irq_alloc_info *info)
2818{
2819	if (info && info->ioapic.valid) {
2820		data->is_level = info->ioapic.is_level;
2821		data->active_low = info->ioapic.active_low;
2822	} else if (__acpi_get_override_irq(gsi, &data->is_level, &data->active_low) < 0) {
 
2823		/* PCI interrupts are always active low level triggered. */
2824		data->is_level = true;
2825		data->active_low = true;
2826	}
2827}
2828
2829/*
2830 * Configure the I/O-APIC specific fields in the routing entry.
2831 *
2832 * This is important to setup the I/O-APIC specific bits (is_level,
2833 * active_low, masked) because the underlying parent domain will only
2834 * provide the routing information and is oblivious of the I/O-APIC
2835 * specific bits.
2836 *
2837 * The entry is just preconfigured at this point and not written into the
2838 * RTE. This happens later during activation which will fill in the actual
2839 * routing information.
2840 */
2841static void mp_preconfigure_entry(struct mp_chip_data *data)
2842{
2843	struct IO_APIC_route_entry *entry = &data->entry;
2844
2845	memset(entry, 0, sizeof(*entry));
2846	entry->is_level		 = data->is_level;
2847	entry->active_low	 = data->active_low;
 
 
 
 
2848	/*
2849	 * Mask level triggered irqs. Edge triggered irqs are masked
2850	 * by the irq core code in case they fire.
2851	 */
2852	entry->masked		= data->is_level;
 
 
 
2853}
2854
2855int mp_irqdomain_alloc(struct irq_domain *domain, unsigned int virq,
2856		       unsigned int nr_irqs, void *arg)
2857{
2858	struct irq_alloc_info *info = arg;
2859	struct mp_chip_data *data;
2860	struct irq_data *irq_data;
2861	int ret, ioapic, pin;
 
 
 
 
2862	unsigned long flags;
2863
2864	if (!info || nr_irqs > 1)
2865		return -EINVAL;
2866	irq_data = irq_domain_get_irq_data(domain, virq);
2867	if (!irq_data)
2868		return -EINVAL;
2869
2870	ioapic = mp_irqdomain_ioapic_idx(domain);
2871	pin = info->ioapic.pin;
2872	if (irq_find_mapping(domain, (irq_hw_number_t)pin) > 0)
2873		return -EEXIST;
2874
2875	data = kzalloc(sizeof(*data), GFP_KERNEL);
2876	if (!data)
2877		return -ENOMEM;
2878
 
2879	ret = irq_domain_alloc_irqs_parent(domain, virq, nr_irqs, info);
2880	if (ret < 0)
2881		goto free_data;
 
 
2882
2883	INIT_LIST_HEAD(&data->irq_2_pin);
2884	irq_data->hwirq = info->ioapic.pin;
2885	irq_data->chip = (domain->parent == x86_vector_domain) ?
2886			  &ioapic_chip : &ioapic_ir_chip;
2887	irq_data->chip_data = data;
2888	mp_irqdomain_get_attr(mp_pin_to_gsi(ioapic, pin), data, info);
2889
2890	if (!add_pin_to_irq_node(data, ioapic_alloc_attr_node(info), ioapic, pin)) {
2891		ret = -ENOMEM;
2892		goto free_irqs;
2893	}
2894
2895	mp_preconfigure_entry(data);
2896	mp_register_handler(virq, data->is_level);
2897
2898	local_irq_save(flags);
 
 
 
2899	if (virq < nr_legacy_irqs())
2900		legacy_pic->mask(virq);
2901	local_irq_restore(flags);
2902
2903	apic_pr_verbose("IOAPIC[%d]: Preconfigured routing entry (%d-%d -> IRQ %d Level:%i ActiveLow:%i)\n",
2904			ioapic, mpc_ioapic_id(ioapic), pin, virq, data->is_level, data->active_low);
2905	return 0;
 
2906
2907free_irqs:
2908	irq_domain_free_irqs_parent(domain, virq, nr_irqs);
2909free_data:
2910	kfree(data);
2911	return ret;
2912}
2913
2914void mp_irqdomain_free(struct irq_domain *domain, unsigned int virq,
2915		       unsigned int nr_irqs)
2916{
2917	struct irq_data *irq_data;
2918	struct mp_chip_data *data;
2919
2920	BUG_ON(nr_irqs != 1);
2921	irq_data = irq_domain_get_irq_data(domain, virq);
2922	if (irq_data && irq_data->chip_data) {
2923		data = irq_data->chip_data;
2924		__remove_pin_from_irq(data, mp_irqdomain_ioapic_idx(domain), (int)irq_data->hwirq);
 
2925		WARN_ON(!list_empty(&data->irq_2_pin));
2926		kfree(irq_data->chip_data);
2927	}
2928	irq_domain_free_irqs_top(domain, virq, nr_irqs);
2929}
2930
2931int mp_irqdomain_activate(struct irq_domain *domain, struct irq_data *irq_data, bool reserve)
 
2932{
2933	guard(raw_spinlock_irqsave)(&ioapic_lock);
 
 
2934	ioapic_configure_entry(irq_data);
 
2935	return 0;
2936}
2937
2938void mp_irqdomain_deactivate(struct irq_domain *domain,
2939			     struct irq_data *irq_data)
2940{
2941	/* It won't be called for IRQ with multiple IOAPIC pins associated */
2942	ioapic_mask_entry(mp_irqdomain_ioapic_idx(domain), (int)irq_data->hwirq);
 
2943}
2944
2945int mp_irqdomain_ioapic_idx(struct irq_domain *domain)
2946{
2947	return (int)(long)domain->host_data;
2948}
2949
2950const struct irq_domain_ops mp_ioapic_irqdomain_ops = {
2951	.alloc		= mp_irqdomain_alloc,
2952	.free		= mp_irqdomain_free,
2953	.activate	= mp_irqdomain_activate,
2954	.deactivate	= mp_irqdomain_deactivate,
2955};
v5.9
   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
  52#include <asm/irqdomain.h>
  53#include <asm/io.h>
  54#include <asm/smp.h>
  55#include <asm/cpu.h>
  56#include <asm/desc.h>
  57#include <asm/proto.h>
  58#include <asm/acpi.h>
  59#include <asm/dma.h>
  60#include <asm/timer.h>
  61#include <asm/time.h>
  62#include <asm/i8259.h>
  63#include <asm/setup.h>
  64#include <asm/irq_remapping.h>
  65#include <asm/hw_irq.h>
  66
  67#include <asm/apic.h>
 
 
  68
  69#define	for_each_ioapic(idx)		\
  70	for ((idx) = 0; (idx) < nr_ioapics; (idx)++)
  71#define	for_each_ioapic_reverse(idx)	\
  72	for ((idx) = nr_ioapics - 1; (idx) >= 0; (idx)--)
  73#define	for_each_pin(idx, pin)		\
  74	for ((pin) = 0; (pin) < ioapics[(idx)].nr_registers; (pin)++)
  75#define	for_each_ioapic_pin(idx, pin)	\
  76	for_each_ioapic((idx))		\
  77		for_each_pin((idx), (pin))
  78#define for_each_irq_pin(entry, head) \
  79	list_for_each_entry(entry, &head, list)
  80
  81static DEFINE_RAW_SPINLOCK(ioapic_lock);
  82static DEFINE_MUTEX(ioapic_mutex);
  83static unsigned int ioapic_dynirq_base;
  84static int ioapic_initialized;
  85
  86struct irq_pin_list {
  87	struct list_head list;
  88	int apic, pin;
  89};
  90
  91struct mp_chip_data {
  92	struct list_head irq_2_pin;
  93	struct IO_APIC_route_entry entry;
  94	int trigger;
  95	int polarity;
  96	u32 count;
  97	bool isa_irq;
  98};
  99
 100struct mp_ioapic_gsi {
 101	u32 gsi_base;
 102	u32 gsi_end;
 103};
 104
 105static struct ioapic {
 106	/*
 107	 * # of IRQ routing registers
 108	 */
 109	int nr_registers;
 110	/*
 111	 * Saved state during suspend/resume, or while enabling intr-remap.
 112	 */
 113	struct IO_APIC_route_entry *saved_registers;
 114	/* I/O APIC config */
 115	struct mpc_ioapic mp_config;
 116	/* IO APIC gsi routing info */
 117	struct mp_ioapic_gsi  gsi_config;
 118	struct ioapic_domain_cfg irqdomain_cfg;
 119	struct irq_domain *irqdomain;
 120	struct resource *iomem_res;
 121} ioapics[MAX_IO_APICS];
 122
 123#define mpc_ioapic_ver(ioapic_idx)	ioapics[ioapic_idx].mp_config.apicver
 124
 125int mpc_ioapic_id(int ioapic_idx)
 126{
 127	return ioapics[ioapic_idx].mp_config.apicid;
 128}
 129
 130unsigned int mpc_ioapic_addr(int ioapic_idx)
 131{
 132	return ioapics[ioapic_idx].mp_config.apicaddr;
 133}
 134
 135static inline struct mp_ioapic_gsi *mp_ioapic_gsi_routing(int ioapic_idx)
 136{
 137	return &ioapics[ioapic_idx].gsi_config;
 138}
 139
 140static inline int mp_ioapic_pin_count(int ioapic)
 141{
 142	struct mp_ioapic_gsi *gsi_cfg = mp_ioapic_gsi_routing(ioapic);
 143
 144	return gsi_cfg->gsi_end - gsi_cfg->gsi_base + 1;
 145}
 146
 147static inline u32 mp_pin_to_gsi(int ioapic, int pin)
 148{
 149	return mp_ioapic_gsi_routing(ioapic)->gsi_base + pin;
 150}
 151
 152static inline bool mp_is_legacy_irq(int irq)
 153{
 154	return irq >= 0 && irq < nr_legacy_irqs();
 155}
 156
 157static inline struct irq_domain *mp_ioapic_irqdomain(int ioapic)
 158{
 159	return ioapics[ioapic].irqdomain;
 160}
 161
 162int nr_ioapics;
 163
 164/* The one past the highest gsi number used */
 165u32 gsi_top;
 166
 167/* MP IRQ source entries */
 168struct mpc_intsrc mp_irqs[MAX_IRQ_SOURCES];
 169
 170/* # of MP IRQ source entries */
 171int mp_irq_entries;
 172
 173#ifdef CONFIG_EISA
 174int mp_bus_id_to_type[MAX_MP_BUSSES];
 175#endif
 176
 177DECLARE_BITMAP(mp_bus_not_pci, MAX_MP_BUSSES);
 178
 179int skip_ioapic_setup;
 180
 181/**
 182 * disable_ioapic_support() - disables ioapic support at runtime
 183 */
 184void disable_ioapic_support(void)
 185{
 186#ifdef CONFIG_PCI
 187	noioapicquirk = 1;
 188	noioapicreroute = -1;
 189#endif
 190	skip_ioapic_setup = 1;
 191}
 192
 193static int __init parse_noapic(char *str)
 194{
 195	/* disable IO-APIC */
 196	disable_ioapic_support();
 197	return 0;
 198}
 199early_param("noapic", parse_noapic);
 200
 201/* Will be called in mpparse/acpi/sfi codes for saving IRQ info */
 202void mp_save_irq(struct mpc_intsrc *m)
 203{
 204	int i;
 205
 206	apic_printk(APIC_VERBOSE, "Int: type %d, pol %d, trig %d, bus %02x,"
 207		" IRQ %02x, APIC ID %x, APIC INT %02x\n",
 208		m->irqtype, m->irqflag & 3, (m->irqflag >> 2) & 3, m->srcbus,
 209		m->srcbusirq, m->dstapic, m->dstirq);
 210
 211	for (i = 0; i < mp_irq_entries; i++) {
 212		if (!memcmp(&mp_irqs[i], m, sizeof(*m)))
 213			return;
 214	}
 215
 216	memcpy(&mp_irqs[mp_irq_entries], m, sizeof(*m));
 217	if (++mp_irq_entries == MAX_IRQ_SOURCES)
 218		panic("Max # of irq sources exceeded!!\n");
 219}
 220
 221static void alloc_ioapic_saved_registers(int idx)
 222{
 223	size_t size;
 224
 225	if (ioapics[idx].saved_registers)
 226		return;
 227
 228	size = sizeof(struct IO_APIC_route_entry) * ioapics[idx].nr_registers;
 229	ioapics[idx].saved_registers = kzalloc(size, GFP_KERNEL);
 230	if (!ioapics[idx].saved_registers)
 231		pr_err("IOAPIC %d: suspend/resume impossible!\n", idx);
 232}
 233
 234static void free_ioapic_saved_registers(int idx)
 235{
 236	kfree(ioapics[idx].saved_registers);
 237	ioapics[idx].saved_registers = NULL;
 238}
 239
 240int __init arch_early_ioapic_init(void)
 241{
 242	int i;
 243
 244	if (!nr_legacy_irqs())
 245		io_apic_irqs = ~0UL;
 246
 247	for_each_ioapic(i)
 248		alloc_ioapic_saved_registers(i);
 249
 250	return 0;
 251}
 252
 253struct io_apic {
 254	unsigned int index;
 255	unsigned int unused[3];
 256	unsigned int data;
 257	unsigned int unused2[11];
 258	unsigned int eoi;
 259};
 260
 261static __attribute_const__ struct io_apic __iomem *io_apic_base(int idx)
 262{
 263	return (void __iomem *) __fix_to_virt(FIX_IO_APIC_BASE_0 + idx)
 264		+ (mpc_ioapic_addr(idx) & ~PAGE_MASK);
 265}
 266
 267static inline void io_apic_eoi(unsigned int apic, unsigned int vector)
 268{
 269	struct io_apic __iomem *io_apic = io_apic_base(apic);
 
 270	writel(vector, &io_apic->eoi);
 271}
 272
 273unsigned int native_io_apic_read(unsigned int apic, unsigned int reg)
 274{
 275	struct io_apic __iomem *io_apic = io_apic_base(apic);
 
 276	writel(reg, &io_apic->index);
 277	return readl(&io_apic->data);
 278}
 279
 280static void io_apic_write(unsigned int apic, unsigned int reg,
 281			  unsigned int value)
 282{
 283	struct io_apic __iomem *io_apic = io_apic_base(apic);
 284
 285	writel(reg, &io_apic->index);
 286	writel(value, &io_apic->data);
 287}
 288
 289union entry_union {
 290	struct { u32 w1, w2; };
 291	struct IO_APIC_route_entry entry;
 292};
 293
 294static struct IO_APIC_route_entry __ioapic_read_entry(int apic, int pin)
 295{
 296	union entry_union eu;
 297
 298	eu.w1 = io_apic_read(apic, 0x10 + 2 * pin);
 299	eu.w2 = io_apic_read(apic, 0x11 + 2 * pin);
 300
 301	return eu.entry;
 302}
 303
 304static struct IO_APIC_route_entry ioapic_read_entry(int apic, int pin)
 305{
 306	union entry_union eu;
 307	unsigned long flags;
 308
 309	raw_spin_lock_irqsave(&ioapic_lock, flags);
 310	eu.entry = __ioapic_read_entry(apic, pin);
 311	raw_spin_unlock_irqrestore(&ioapic_lock, flags);
 312
 313	return eu.entry;
 314}
 315
 316/*
 317 * When we write a new IO APIC routing entry, we need to write the high
 318 * word first! If the mask bit in the low word is clear, we will enable
 319 * the interrupt, and we need to make sure the entry is fully populated
 320 * before that happens.
 321 */
 322static void __ioapic_write_entry(int apic, int pin, struct IO_APIC_route_entry e)
 323{
 324	union entry_union eu = {{0, 0}};
 325
 326	eu.entry = e;
 327	io_apic_write(apic, 0x11 + 2*pin, eu.w2);
 328	io_apic_write(apic, 0x10 + 2*pin, eu.w1);
 329}
 330
 331static void ioapic_write_entry(int apic, int pin, struct IO_APIC_route_entry e)
 332{
 333	unsigned long flags;
 334
 335	raw_spin_lock_irqsave(&ioapic_lock, flags);
 336	__ioapic_write_entry(apic, pin, e);
 337	raw_spin_unlock_irqrestore(&ioapic_lock, flags);
 338}
 339
 340/*
 341 * When we mask an IO APIC routing entry, we need to write the low
 342 * word first, in order to set the mask bit before we change the
 343 * high bits!
 344 */
 345static void ioapic_mask_entry(int apic, int pin)
 346{
 347	unsigned long flags;
 348	union entry_union eu = { .entry.mask = IOAPIC_MASKED };
 349
 350	raw_spin_lock_irqsave(&ioapic_lock, flags);
 351	io_apic_write(apic, 0x10 + 2*pin, eu.w1);
 352	io_apic_write(apic, 0x11 + 2*pin, eu.w2);
 353	raw_spin_unlock_irqrestore(&ioapic_lock, flags);
 354}
 355
 356/*
 357 * The common case is 1:1 IRQ<->pin mappings. Sometimes there are
 358 * shared ISA-space IRQs, so we have to support them. We are super
 359 * fast in the common case, and fast for shared ISA-space IRQs.
 360 */
 361static int __add_pin_to_irq_node(struct mp_chip_data *data,
 362				 int node, int apic, int pin)
 363{
 364	struct irq_pin_list *entry;
 365
 366	/* don't allow duplicates */
 367	for_each_irq_pin(entry, data->irq_2_pin)
 368		if (entry->apic == apic && entry->pin == pin)
 369			return 0;
 
 370
 371	entry = kzalloc_node(sizeof(struct irq_pin_list), GFP_ATOMIC, node);
 372	if (!entry) {
 373		pr_err("can not alloc irq_pin_list (%d,%d,%d)\n",
 374		       node, apic, pin);
 375		return -ENOMEM;
 376	}
 
 377	entry->apic = apic;
 378	entry->pin = pin;
 379	list_add_tail(&entry->list, &data->irq_2_pin);
 380
 381	return 0;
 382}
 383
 384static void __remove_pin_from_irq(struct mp_chip_data *data, int apic, int pin)
 385{
 386	struct irq_pin_list *tmp, *entry;
 387
 388	list_for_each_entry_safe(entry, tmp, &data->irq_2_pin, list)
 389		if (entry->apic == apic && entry->pin == pin) {
 390			list_del(&entry->list);
 391			kfree(entry);
 392			return;
 393		}
 394}
 395
 396static void add_pin_to_irq_node(struct mp_chip_data *data,
 397				int node, int apic, int pin)
 398{
 399	if (__add_pin_to_irq_node(data, node, apic, pin))
 400		panic("IO-APIC: failed to add irq-pin. Can not proceed\n");
 401}
 402
 403/*
 404 * Reroute an IRQ to a different pin.
 405 */
 406static void __init replace_pin_at_irq_node(struct mp_chip_data *data, int node,
 407					   int oldapic, int oldpin,
 408					   int newapic, int newpin)
 409{
 410	struct irq_pin_list *entry;
 411
 412	for_each_irq_pin(entry, data->irq_2_pin) {
 413		if (entry->apic == oldapic && entry->pin == oldpin) {
 414			entry->apic = newapic;
 415			entry->pin = newpin;
 416			/* every one is different, right? */
 417			return;
 418		}
 419	}
 420
 421	/* old apic/pin didn't exist, so just add new ones */
 422	add_pin_to_irq_node(data, node, newapic, newpin);
 423}
 424
 425static void io_apic_modify_irq(struct mp_chip_data *data,
 426			       int mask_and, int mask_or,
 427			       void (*final)(struct irq_pin_list *entry))
 428{
 429	union entry_union eu;
 430	struct irq_pin_list *entry;
 431
 432	eu.entry = data->entry;
 433	eu.w1 &= mask_and;
 434	eu.w1 |= mask_or;
 435	data->entry = eu.entry;
 436
 437	for_each_irq_pin(entry, data->irq_2_pin) {
 438		io_apic_write(entry->apic, 0x10 + 2 * entry->pin, eu.w1);
 439		if (final)
 440			final(entry);
 441	}
 442}
 443
 
 
 
 
 444static void io_apic_sync(struct irq_pin_list *entry)
 445{
 446	/*
 447	 * Synchronize the IO-APIC and the CPU by doing
 448	 * a dummy read from the IO-APIC
 449	 */
 450	struct io_apic __iomem *io_apic;
 451
 452	io_apic = io_apic_base(entry->apic);
 453	readl(&io_apic->data);
 454}
 455
 456static void mask_ioapic_irq(struct irq_data *irq_data)
 457{
 458	struct mp_chip_data *data = irq_data->chip_data;
 459	unsigned long flags;
 460
 461	raw_spin_lock_irqsave(&ioapic_lock, flags);
 462	io_apic_modify_irq(data, ~0, IO_APIC_REDIR_MASKED, &io_apic_sync);
 463	raw_spin_unlock_irqrestore(&ioapic_lock, flags);
 464}
 465
 466static void __unmask_ioapic(struct mp_chip_data *data)
 467{
 468	io_apic_modify_irq(data, ~IO_APIC_REDIR_MASKED, 0, NULL);
 469}
 470
 471static void unmask_ioapic_irq(struct irq_data *irq_data)
 472{
 473	struct mp_chip_data *data = irq_data->chip_data;
 474	unsigned long flags;
 475
 476	raw_spin_lock_irqsave(&ioapic_lock, flags);
 477	__unmask_ioapic(data);
 478	raw_spin_unlock_irqrestore(&ioapic_lock, flags);
 479}
 480
 481/*
 482 * IO-APIC versions below 0x20 don't support EOI register.
 483 * For the record, here is the information about various versions:
 484 *     0Xh     82489DX
 485 *     1Xh     I/OAPIC or I/O(x)APIC which are not PCI 2.2 Compliant
 486 *     2Xh     I/O(x)APIC which is PCI 2.2 Compliant
 487 *     30h-FFh Reserved
 488 *
 489 * Some of the Intel ICH Specs (ICH2 to ICH5) documents the io-apic
 490 * version as 0x2. This is an error with documentation and these ICH chips
 491 * use io-apic's of version 0x20.
 492 *
 493 * For IO-APIC's with EOI register, we use that to do an explicit EOI.
 494 * Otherwise, we simulate the EOI message manually by changing the trigger
 495 * mode to edge and then back to level, with RTE being masked during this.
 496 */
 497static void __eoi_ioapic_pin(int apic, int pin, int vector)
 498{
 499	if (mpc_ioapic_ver(apic) >= 0x20) {
 500		io_apic_eoi(apic, vector);
 501	} else {
 502		struct IO_APIC_route_entry entry, entry1;
 503
 504		entry = entry1 = __ioapic_read_entry(apic, pin);
 505
 506		/*
 507		 * Mask the entry and change the trigger mode to edge.
 508		 */
 509		entry1.mask = IOAPIC_MASKED;
 510		entry1.trigger = IOAPIC_EDGE;
 511
 512		__ioapic_write_entry(apic, pin, entry1);
 513
 514		/*
 515		 * Restore the previous level triggered entry.
 516		 */
 517		__ioapic_write_entry(apic, pin, entry);
 518	}
 519}
 520
 521static void eoi_ioapic_pin(int vector, struct mp_chip_data *data)
 522{
 523	unsigned long flags;
 524	struct irq_pin_list *entry;
 525
 526	raw_spin_lock_irqsave(&ioapic_lock, flags);
 527	for_each_irq_pin(entry, data->irq_2_pin)
 528		__eoi_ioapic_pin(entry->apic, entry->pin, vector);
 529	raw_spin_unlock_irqrestore(&ioapic_lock, flags);
 530}
 531
 532static void clear_IO_APIC_pin(unsigned int apic, unsigned int pin)
 533{
 534	struct IO_APIC_route_entry entry;
 535
 536	/* Check delivery_mode to be sure we're not clearing an SMI pin */
 537	entry = ioapic_read_entry(apic, pin);
 538	if (entry.delivery_mode == dest_SMI)
 539		return;
 540
 541	/*
 542	 * Make sure the entry is masked and re-read the contents to check
 543	 * if it is a level triggered pin and if the remote-IRR is set.
 544	 */
 545	if (entry.mask == IOAPIC_UNMASKED) {
 546		entry.mask = IOAPIC_MASKED;
 547		ioapic_write_entry(apic, pin, entry);
 548		entry = ioapic_read_entry(apic, pin);
 549	}
 550
 551	if (entry.irr) {
 552		unsigned long flags;
 553
 554		/*
 555		 * Make sure the trigger mode is set to level. Explicit EOI
 556		 * doesn't clear the remote-IRR if the trigger mode is not
 557		 * set to level.
 558		 */
 559		if (entry.trigger == IOAPIC_EDGE) {
 560			entry.trigger = IOAPIC_LEVEL;
 561			ioapic_write_entry(apic, pin, entry);
 562		}
 563		raw_spin_lock_irqsave(&ioapic_lock, flags);
 564		__eoi_ioapic_pin(apic, pin, entry.vector);
 565		raw_spin_unlock_irqrestore(&ioapic_lock, flags);
 566	}
 567
 568	/*
 569	 * Clear the rest of the bits in the IO-APIC RTE except for the mask
 570	 * bit.
 571	 */
 572	ioapic_mask_entry(apic, pin);
 573	entry = ioapic_read_entry(apic, pin);
 574	if (entry.irr)
 575		pr_err("Unable to reset IRR for apic: %d, pin :%d\n",
 576		       mpc_ioapic_id(apic), pin);
 577}
 578
 579void clear_IO_APIC (void)
 580{
 581	int apic, pin;
 582
 583	for_each_ioapic_pin(apic, pin)
 584		clear_IO_APIC_pin(apic, pin);
 585}
 586
 587#ifdef CONFIG_X86_32
 588/*
 589 * support for broken MP BIOSs, enables hand-redirection of PIRQ0-7 to
 590 * specific CPU-side IRQs.
 591 */
 592
 593#define MAX_PIRQS 8
 594static int pirq_entries[MAX_PIRQS] = {
 595	[0 ... MAX_PIRQS - 1] = -1
 596};
 597
 598static int __init ioapic_pirq_setup(char *str)
 599{
 600	int i, max;
 601	int ints[MAX_PIRQS+1];
 602
 603	get_options(str, ARRAY_SIZE(ints), ints);
 604
 605	apic_printk(APIC_VERBOSE, KERN_INFO
 606			"PIRQ redirection, working around broken MP-BIOS.\n");
 607	max = MAX_PIRQS;
 608	if (ints[0] < MAX_PIRQS)
 609		max = ints[0];
 610
 611	for (i = 0; i < max; i++) {
 612		apic_printk(APIC_VERBOSE, KERN_DEBUG
 613				"... PIRQ%d -> IRQ %d\n", i, ints[i+1]);
 614		/*
 615		 * PIRQs are mapped upside down, usually.
 616		 */
 617		pirq_entries[MAX_PIRQS-i-1] = ints[i+1];
 618	}
 619	return 1;
 620}
 621
 622__setup("pirq=", ioapic_pirq_setup);
 623#endif /* CONFIG_X86_32 */
 624
 625/*
 626 * Saves all the IO-APIC RTE's
 627 */
 628int save_ioapic_entries(void)
 629{
 630	int apic, pin;
 631	int err = 0;
 632
 633	for_each_ioapic(apic) {
 634		if (!ioapics[apic].saved_registers) {
 635			err = -ENOMEM;
 636			continue;
 637		}
 638
 639		for_each_pin(apic, pin)
 640			ioapics[apic].saved_registers[pin] =
 641				ioapic_read_entry(apic, pin);
 642	}
 643
 644	return err;
 645}
 646
 647/*
 648 * Mask all IO APIC entries.
 649 */
 650void mask_ioapic_entries(void)
 651{
 652	int apic, pin;
 653
 654	for_each_ioapic(apic) {
 655		if (!ioapics[apic].saved_registers)
 656			continue;
 657
 658		for_each_pin(apic, pin) {
 659			struct IO_APIC_route_entry entry;
 660
 661			entry = ioapics[apic].saved_registers[pin];
 662			if (entry.mask == IOAPIC_UNMASKED) {
 663				entry.mask = IOAPIC_MASKED;
 664				ioapic_write_entry(apic, pin, entry);
 665			}
 666		}
 667	}
 668}
 669
 670/*
 671 * Restore IO APIC entries which was saved in the ioapic structure.
 672 */
 673int restore_ioapic_entries(void)
 674{
 675	int apic, pin;
 676
 677	for_each_ioapic(apic) {
 678		if (!ioapics[apic].saved_registers)
 679			continue;
 680
 681		for_each_pin(apic, pin)
 682			ioapic_write_entry(apic, pin,
 683					   ioapics[apic].saved_registers[pin]);
 684	}
 685	return 0;
 686}
 687
 688/*
 689 * Find the IRQ entry number of a certain pin.
 690 */
 691static int find_irq_entry(int ioapic_idx, int pin, int type)
 692{
 693	int i;
 694
 695	for (i = 0; i < mp_irq_entries; i++)
 696		if (mp_irqs[i].irqtype == type &&
 697		    (mp_irqs[i].dstapic == mpc_ioapic_id(ioapic_idx) ||
 698		     mp_irqs[i].dstapic == MP_APIC_ALL) &&
 699		    mp_irqs[i].dstirq == pin)
 700			return i;
 
 701
 702	return -1;
 703}
 704
 705/*
 706 * Find the pin to which IRQ[irq] (ISA) is connected
 707 */
 708static int __init find_isa_irq_pin(int irq, int type)
 709{
 710	int i;
 711
 712	for (i = 0; i < mp_irq_entries; i++) {
 713		int lbus = mp_irqs[i].srcbus;
 714
 715		if (test_bit(lbus, mp_bus_not_pci) &&
 716		    (mp_irqs[i].irqtype == type) &&
 717		    (mp_irqs[i].srcbusirq == irq))
 718
 719			return mp_irqs[i].dstirq;
 720	}
 721	return -1;
 722}
 723
 724static int __init find_isa_irq_apic(int irq, int type)
 725{
 726	int i;
 727
 728	for (i = 0; i < mp_irq_entries; i++) {
 729		int lbus = mp_irqs[i].srcbus;
 730
 731		if (test_bit(lbus, mp_bus_not_pci) &&
 732		    (mp_irqs[i].irqtype == type) &&
 733		    (mp_irqs[i].srcbusirq == irq))
 734			break;
 735	}
 736
 737	if (i < mp_irq_entries) {
 738		int ioapic_idx;
 739
 740		for_each_ioapic(ioapic_idx)
 741			if (mpc_ioapic_id(ioapic_idx) == mp_irqs[i].dstapic)
 742				return ioapic_idx;
 
 743	}
 744
 745	return -1;
 746}
 747
 748#ifdef CONFIG_EISA
 749/*
 750 * EISA Edge/Level control register, ELCR
 751 */
 752static int EISA_ELCR(unsigned int irq)
 753{
 754	if (irq < nr_legacy_irqs()) {
 755		unsigned int port = 0x4d0 + (irq >> 3);
 756		return (inb(port) >> (irq & 7)) & 1;
 757	}
 758	apic_printk(APIC_VERBOSE, KERN_INFO
 759			"Broken MPtable reports ISA irq %d\n", irq);
 760	return 0;
 761}
 762
 763#endif
 764
 765/* ISA interrupts are always active high edge triggered,
 766 * when listed as conforming in the MP table. */
 767
 768#define default_ISA_trigger(idx)	(IOAPIC_EDGE)
 769#define default_ISA_polarity(idx)	(IOAPIC_POL_HIGH)
 770
 771/* EISA interrupts are always polarity zero and can be edge or level
 772 * trigger depending on the ELCR value.  If an interrupt is listed as
 773 * EISA conforming in the MP table, that means its trigger type must
 774 * be read in from the ELCR */
 775
 776#define default_EISA_trigger(idx)	(EISA_ELCR(mp_irqs[idx].srcbusirq))
 777#define default_EISA_polarity(idx)	default_ISA_polarity(idx)
 778
 779/* PCI interrupts are always active low level triggered,
 780 * when listed as conforming in the MP table. */
 781
 782#define default_PCI_trigger(idx)	(IOAPIC_LEVEL)
 783#define default_PCI_polarity(idx)	(IOAPIC_POL_LOW)
 784
 785static int irq_polarity(int idx)
 786{
 787	int bus = mp_irqs[idx].srcbus;
 788
 789	/*
 790	 * Determine IRQ line polarity (high active or low active):
 791	 */
 792	switch (mp_irqs[idx].irqflag & MP_IRQPOL_MASK) {
 793	case MP_IRQPOL_DEFAULT:
 794		/* conforms to spec, ie. bus-type dependent polarity */
 795		if (test_bit(bus, mp_bus_not_pci))
 796			return default_ISA_polarity(idx);
 797		else
 798			return default_PCI_polarity(idx);
 799	case MP_IRQPOL_ACTIVE_HIGH:
 800		return IOAPIC_POL_HIGH;
 801	case MP_IRQPOL_RESERVED:
 802		pr_warn("IOAPIC: Invalid polarity: 2, defaulting to low\n");
 803		fallthrough;
 804	case MP_IRQPOL_ACTIVE_LOW:
 805	default: /* Pointless default required due to do gcc stupidity */
 806		return IOAPIC_POL_LOW;
 807	}
 808}
 809
 810#ifdef CONFIG_EISA
 811static int eisa_irq_trigger(int idx, int bus, int trigger)
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 812{
 813	switch (mp_bus_id_to_type[bus]) {
 814	case MP_BUS_PCI:
 815	case MP_BUS_ISA:
 816		return trigger;
 817	case MP_BUS_EISA:
 818		return default_EISA_trigger(idx);
 819	}
 820	pr_warn("IOAPIC: Invalid srcbus: %d defaulting to level\n", bus);
 821	return IOAPIC_LEVEL;
 822}
 823#else
 824static inline int eisa_irq_trigger(int idx, int bus, int trigger)
 825{
 826	return trigger;
 827}
 828#endif
 829
 830static int irq_trigger(int idx)
 831{
 832	int bus = mp_irqs[idx].srcbus;
 833	int trigger;
 834
 835	/*
 836	 * Determine IRQ trigger mode (edge or level sensitive):
 837	 */
 838	switch (mp_irqs[idx].irqflag & MP_IRQTRIG_MASK) {
 839	case MP_IRQTRIG_DEFAULT:
 840		/* conforms to spec, ie. bus-type dependent trigger mode */
 841		if (test_bit(bus, mp_bus_not_pci))
 842			trigger = default_ISA_trigger(idx);
 843		else
 844			trigger = default_PCI_trigger(idx);
 845		/* Take EISA into account */
 846		return eisa_irq_trigger(idx, bus, trigger);
 847	case MP_IRQTRIG_EDGE:
 848		return IOAPIC_EDGE;
 849	case MP_IRQTRIG_RESERVED:
 850		pr_warn("IOAPIC: Invalid trigger mode 2 defaulting to level\n");
 851		fallthrough;
 852	case MP_IRQTRIG_LEVEL:
 853	default: /* Pointless default required due to do gcc stupidity */
 854		return IOAPIC_LEVEL;
 855	}
 856}
 857
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 858void ioapic_set_alloc_attr(struct irq_alloc_info *info, int node,
 859			   int trigger, int polarity)
 860{
 861	init_irq_alloc_info(info, NULL);
 862	info->type = X86_IRQ_ALLOC_TYPE_IOAPIC;
 863	info->ioapic_node = node;
 864	info->ioapic_trigger = trigger;
 865	info->ioapic_polarity = polarity;
 866	info->ioapic_valid = 1;
 867}
 868
 869#ifndef CONFIG_ACPI
 870int acpi_get_override_irq(u32 gsi, int *trigger, int *polarity);
 871#endif
 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	int trigger, polarity;
 878
 879	copy_irq_alloc_info(dst, src);
 880	dst->type = X86_IRQ_ALLOC_TYPE_IOAPIC;
 881	dst->ioapic_id = 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_trigger = src->ioapic_trigger;
 887		dst->ioapic_polarity = src->ioapic_polarity;
 888	} else {
 889		dst->ioapic_node = NUMA_NO_NODE;
 890		if (acpi_get_override_irq(gsi, &trigger, &polarity) >= 0) {
 891			dst->ioapic_trigger = trigger;
 892			dst->ioapic_polarity = polarity;
 893		} else {
 894			/*
 895			 * PCI interrupts are always active low level
 896			 * triggered.
 897			 */
 898			dst->ioapic_trigger = IOAPIC_LEVEL;
 899			dst->ioapic_polarity = IOAPIC_POL_LOW;
 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, unsigned long trigger)
 910{
 911	irq_flow_handler_t hdl;
 912	bool fasteoi;
 913
 914	if (trigger) {
 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 attirbutes. 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_trigger != data->trigger)
 937			mp_register_handler(irq, info->ioapic_trigger);
 938		data->entry.trigger = data->trigger = info->ioapic_trigger;
 939		data->entry.polarity = data->polarity = info->ioapic_polarity;
 940	}
 941
 942	return data->trigger == info->ioapic_trigger &&
 943	       data->polarity == info->ioapic_polarity;
 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 assoicated 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
1038	mutex_lock(&ioapic_mutex);
1039	if (!(flags & IOAPIC_MAP_ALLOC)) {
1040		if (!legacy) {
1041			irq = irq_find_mapping(domain, pin);
1042			if (irq == 0)
1043				irq = -ENOENT;
1044		}
1045	} else {
1046		ioapic_copy_alloc_attr(&tmp, info, gsi, ioapic, pin);
1047		if (legacy)
1048			irq = alloc_isa_irq_from_domain(domain, irq,
1049							ioapic, pin, &tmp);
1050		else if ((irq = irq_find_mapping(domain, pin)) == 0)
1051			irq = alloc_irq_from_domain(domain, ioapic, gsi, &tmp);
1052		else if (!mp_check_pin_attr(irq, &tmp))
1053			irq = -EBUSY;
1054		if (irq >= 0) {
1055			data = irq_get_chip_data(irq);
1056			data->count++;
1057		}
1058	}
1059	mutex_unlock(&ioapic_mutex);
1060
1061	return irq;
1062}
1063
1064static int pin_2_irq(int idx, int ioapic, int pin, unsigned int flags)
1065{
1066	u32 gsi = mp_pin_to_gsi(ioapic, pin);
1067
1068	/*
1069	 * Debugging check, we are in big trouble if this message pops up!
1070	 */
1071	if (mp_irqs[idx].dstirq != pin)
1072		pr_err("broken BIOS or MPTABLE parser, ayiee!!\n");
1073
1074#ifdef CONFIG_X86_32
1075	/*
1076	 * PCI IRQ command line redirection. Yes, limits are hardcoded.
1077	 */
1078	if ((pin >= 16) && (pin <= 23)) {
1079		if (pirq_entries[pin-16] != -1) {
1080			if (!pirq_entries[pin-16]) {
1081				apic_printk(APIC_VERBOSE, KERN_DEBUG
1082						"disabling PIRQ%d\n", pin-16);
1083			} else {
1084				int irq = pirq_entries[pin-16];
1085				apic_printk(APIC_VERBOSE, KERN_DEBUG
1086						"using PIRQ%d -> IRQ %d\n",
1087						pin-16, irq);
1088				return irq;
1089			}
1090		}
1091	}
1092#endif
1093
1094	return  mp_map_pin_to_irq(gsi, idx, ioapic, pin, flags, NULL);
1095}
1096
1097int mp_map_gsi_to_irq(u32 gsi, unsigned int flags, struct irq_alloc_info *info)
1098{
1099	int ioapic, pin, idx;
1100
1101	ioapic = mp_find_ioapic(gsi);
1102	if (ioapic < 0)
1103		return -ENODEV;
1104
1105	pin = mp_find_ioapic_pin(ioapic, gsi);
1106	idx = find_irq_entry(ioapic, pin, mp_INT);
1107	if ((flags & IOAPIC_MAP_CHECK) && idx < 0)
1108		return -ENODEV;
1109
1110	return mp_map_pin_to_irq(gsi, idx, ioapic, pin, flags, info);
1111}
1112
1113void mp_unmap_irq(int irq)
1114{
1115	struct irq_data *irq_data = irq_get_irq_data(irq);
1116	struct mp_chip_data *data;
1117
1118	if (!irq_data || !irq_data->domain)
1119		return;
1120
1121	data = irq_data->chip_data;
1122	if (!data || data->isa_irq)
1123		return;
1124
1125	mutex_lock(&ioapic_mutex);
1126	if (--data->count == 0)
1127		irq_domain_free_irqs(irq, 1);
1128	mutex_unlock(&ioapic_mutex);
1129}
1130
1131/*
1132 * Find a specific PCI IRQ entry.
1133 * Not an __init, possibly needed by modules
1134 */
1135int IO_APIC_get_PCI_irq_vector(int bus, int slot, int pin)
1136{
1137	int irq, i, best_ioapic = -1, best_idx = -1;
1138
1139	apic_printk(APIC_DEBUG,
1140		    "querying PCI -> IRQ mapping bus:%d, slot:%d, pin:%d.\n",
1141		    bus, slot, pin);
1142	if (test_bit(bus, mp_bus_not_pci)) {
1143		apic_printk(APIC_VERBOSE,
1144			    "PCI BIOS passed nonexistent PCI bus %d!\n", bus);
1145		return -1;
1146	}
1147
1148	for (i = 0; i < mp_irq_entries; i++) {
1149		int lbus = mp_irqs[i].srcbus;
1150		int ioapic_idx, found = 0;
1151
1152		if (bus != lbus || mp_irqs[i].irqtype != mp_INT ||
1153		    slot != ((mp_irqs[i].srcbusirq >> 2) & 0x1f))
1154			continue;
1155
1156		for_each_ioapic(ioapic_idx)
1157			if (mpc_ioapic_id(ioapic_idx) == mp_irqs[i].dstapic ||
1158			    mp_irqs[i].dstapic == MP_APIC_ALL) {
1159				found = 1;
1160				break;
1161			}
1162		if (!found)
1163			continue;
1164
1165		/* Skip ISA IRQs */
1166		irq = pin_2_irq(i, ioapic_idx, mp_irqs[i].dstirq, 0);
1167		if (irq > 0 && !IO_APIC_IRQ(irq))
1168			continue;
1169
1170		if (pin == (mp_irqs[i].srcbusirq & 3)) {
1171			best_idx = i;
1172			best_ioapic = ioapic_idx;
1173			goto out;
1174		}
1175
1176		/*
1177		 * Use the first all-but-pin matching entry as a
1178		 * best-guess fuzzy result for broken mptables.
1179		 */
1180		if (best_idx < 0) {
1181			best_idx = i;
1182			best_ioapic = ioapic_idx;
1183		}
1184	}
1185	if (best_idx < 0)
1186		return -1;
1187
1188out:
1189	return pin_2_irq(best_idx, best_ioapic, mp_irqs[best_idx].dstirq,
1190			 IOAPIC_MAP_ALLOC);
1191}
1192EXPORT_SYMBOL(IO_APIC_get_PCI_irq_vector);
1193
1194static struct irq_chip ioapic_chip, ioapic_ir_chip;
1195
1196static void __init setup_IO_APIC_irqs(void)
1197{
1198	unsigned int ioapic, pin;
1199	int idx;
1200
1201	apic_printk(APIC_VERBOSE, KERN_DEBUG "init IO_APIC IRQs\n");
1202
1203	for_each_ioapic_pin(ioapic, pin) {
1204		idx = find_irq_entry(ioapic, pin, mp_INT);
1205		if (idx < 0)
1206			apic_printk(APIC_VERBOSE,
1207				    KERN_DEBUG " apic %d pin %d not connected\n",
1208				    mpc_ioapic_id(ioapic), pin);
1209		else
1210			pin_2_irq(idx, ioapic, pin,
1211				  ioapic ? 0 : IOAPIC_MAP_ALLOC);
1212	}
1213}
1214
1215void ioapic_zap_locks(void)
1216{
1217	raw_spin_lock_init(&ioapic_lock);
1218}
1219
1220static void io_apic_print_entries(unsigned int apic, unsigned int nr_entries)
1221{
 
 
1222	int i;
1223	char buf[256];
1224	struct IO_APIC_route_entry entry;
1225	struct IR_IO_APIC_route_entry *ir_entry = (void *)&entry;
1226
1227	printk(KERN_DEBUG "IOAPIC %d:\n", apic);
1228	for (i = 0; i <= nr_entries; i++) {
1229		entry = ioapic_read_entry(apic, i);
1230		snprintf(buf, sizeof(buf),
1231			 " pin%02x, %s, %s, %s, V(%02X), IRR(%1d), S(%1d)",
1232			 i,
1233			 entry.mask == IOAPIC_MASKED ? "disabled" : "enabled ",
1234			 entry.trigger == IOAPIC_LEVEL ? "level" : "edge ",
1235			 entry.polarity == IOAPIC_POL_LOW ? "low " : "high",
1236			 entry.vector, entry.irr, entry.delivery_status);
1237		if (ir_entry->format)
1238			printk(KERN_DEBUG "%s, remapped, I(%04X),  Z(%X)\n",
1239			       buf, (ir_entry->index2 << 15) | ir_entry->index,
1240			       ir_entry->zero);
1241		else
1242			printk(KERN_DEBUG "%s, %s, D(%02X), M(%1d)\n",
1243			       buf,
1244			       entry.dest_mode == IOAPIC_DEST_MODE_LOGICAL ?
1245			       "logical " : "physical",
1246			       entry.dest, entry.delivery_mode);
1247	}
1248}
1249
1250static void __init print_IO_APIC(int ioapic_idx)
1251{
1252	union IO_APIC_reg_00 reg_00;
1253	union IO_APIC_reg_01 reg_01;
1254	union IO_APIC_reg_02 reg_02;
1255	union IO_APIC_reg_03 reg_03;
1256	unsigned long flags;
1257
1258	raw_spin_lock_irqsave(&ioapic_lock, flags);
1259	reg_00.raw = io_apic_read(ioapic_idx, 0);
1260	reg_01.raw = io_apic_read(ioapic_idx, 1);
1261	if (reg_01.bits.version >= 0x10)
1262		reg_02.raw = io_apic_read(ioapic_idx, 2);
1263	if (reg_01.bits.version >= 0x20)
1264		reg_03.raw = io_apic_read(ioapic_idx, 3);
1265	raw_spin_unlock_irqrestore(&ioapic_lock, flags);
1266
1267	printk(KERN_DEBUG "IO APIC #%d......\n", mpc_ioapic_id(ioapic_idx));
1268	printk(KERN_DEBUG ".... register #00: %08X\n", reg_00.raw);
1269	printk(KERN_DEBUG ".......    : physical APIC id: %02X\n", reg_00.bits.ID);
1270	printk(KERN_DEBUG ".......    : Delivery Type: %X\n", reg_00.bits.delivery_type);
1271	printk(KERN_DEBUG ".......    : LTS          : %X\n", reg_00.bits.LTS);
1272
1273	printk(KERN_DEBUG ".... register #01: %08X\n", *(int *)&reg_01);
1274	printk(KERN_DEBUG ".......     : max redirection entries: %02X\n",
1275		reg_01.bits.entries);
1276
1277	printk(KERN_DEBUG ".......     : PRQ implemented: %X\n", reg_01.bits.PRQ);
1278	printk(KERN_DEBUG ".......     : IO APIC version: %02X\n",
1279		reg_01.bits.version);
1280
1281	/*
1282	 * Some Intel chipsets with IO APIC VERSION of 0x1? don't have reg_02,
1283	 * but the value of reg_02 is read as the previous read register
1284	 * value, so ignore it if reg_02 == reg_01.
1285	 */
1286	if (reg_01.bits.version >= 0x10 && reg_02.raw != reg_01.raw) {
1287		printk(KERN_DEBUG ".... register #02: %08X\n", reg_02.raw);
1288		printk(KERN_DEBUG ".......     : arbitration: %02X\n", reg_02.bits.arbitration);
1289	}
1290
1291	/*
1292	 * Some Intel chipsets with IO APIC VERSION of 0x2? don't have reg_02
1293	 * or reg_03, but the value of reg_0[23] is read as the previous read
1294	 * register value, so ignore it if reg_03 == reg_0[12].
1295	 */
1296	if (reg_01.bits.version >= 0x20 && reg_03.raw != reg_02.raw &&
1297	    reg_03.raw != reg_01.raw) {
1298		printk(KERN_DEBUG ".... register #03: %08X\n", reg_03.raw);
1299		printk(KERN_DEBUG ".......     : Boot DT    : %X\n", reg_03.bits.boot_DT);
1300	}
1301
1302	printk(KERN_DEBUG ".... IRQ redirection table:\n");
1303	io_apic_print_entries(ioapic_idx, reg_01.bits.entries);
1304}
1305
1306void __init print_IO_APICs(void)
1307{
1308	int ioapic_idx;
1309	unsigned int irq;
1310
1311	printk(KERN_DEBUG "number of MP IRQ sources: %d.\n", mp_irq_entries);
1312	for_each_ioapic(ioapic_idx)
1313		printk(KERN_DEBUG "number of IO-APIC #%d registers: %d.\n",
1314		       mpc_ioapic_id(ioapic_idx),
1315		       ioapics[ioapic_idx].nr_registers);
1316
1317	/*
1318	 * We are a bit conservative about what we expect.  We have to
1319	 * know about every hardware change ASAP.
1320	 */
1321	printk(KERN_INFO "testing the IO APIC.......................\n");
1322
1323	for_each_ioapic(ioapic_idx)
1324		print_IO_APIC(ioapic_idx);
1325
1326	printk(KERN_DEBUG "IRQ to pin mappings:\n");
1327	for_each_active_irq(irq) {
1328		struct irq_pin_list *entry;
1329		struct irq_chip *chip;
1330		struct mp_chip_data *data;
1331
1332		chip = irq_get_chip(irq);
1333		if (chip != &ioapic_chip && chip != &ioapic_ir_chip)
1334			continue;
1335		data = irq_get_chip_data(irq);
1336		if (!data)
1337			continue;
1338		if (list_empty(&data->irq_2_pin))
1339			continue;
1340
1341		printk(KERN_DEBUG "IRQ%d ", irq);
1342		for_each_irq_pin(entry, data->irq_2_pin)
1343			pr_cont("-> %d:%d", entry->apic, entry->pin);
1344		pr_cont("\n");
1345	}
1346
1347	printk(KERN_INFO ".................................... done.\n");
1348}
1349
1350/* Where if anywhere is the i8259 connect in external int mode */
1351static struct { int pin, apic; } ioapic_i8259 = { -1, -1 };
1352
1353void __init enable_IO_APIC(void)
1354{
1355	int i8259_apic, i8259_pin;
1356	int apic, pin;
1357
1358	if (skip_ioapic_setup)
1359		nr_ioapics = 0;
1360
1361	if (!nr_legacy_irqs() || !nr_ioapics)
1362		return;
1363
1364	for_each_ioapic_pin(apic, pin) {
1365		/* See if any of the pins is in ExtINT mode */
1366		struct IO_APIC_route_entry entry = ioapic_read_entry(apic, pin);
1367
1368		/* If the interrupt line is enabled and in ExtInt mode
1369		 * I have found the pin where the i8259 is connected.
 
1370		 */
1371		if ((entry.mask == 0) && (entry.delivery_mode == dest_ExtINT)) {
1372			ioapic_i8259.apic = apic;
1373			ioapic_i8259.pin  = pin;
1374			goto found_i8259;
1375		}
1376	}
1377 found_i8259:
1378	/* Look to see what if the MP table has reported the ExtINT */
1379	/* If we could not find the appropriate pin by looking at the ioapic
 
 
1380	 * the i8259 probably is not connected the ioapic but give the
1381	 * mptable a chance anyway.
1382	 */
1383	i8259_pin  = find_isa_irq_pin(0, mp_ExtINT);
1384	i8259_apic = find_isa_irq_apic(0, mp_ExtINT);
1385	/* Trust the MP table if nothing is setup in the hardware */
1386	if ((ioapic_i8259.pin == -1) && (i8259_pin >= 0)) {
1387		printk(KERN_WARNING "ExtINT not setup in hardware but reported by MP table\n");
1388		ioapic_i8259.pin  = i8259_pin;
1389		ioapic_i8259.apic = i8259_apic;
1390	}
1391	/* Complain if the MP table and the hardware disagree */
1392	if (((ioapic_i8259.apic != i8259_apic) || (ioapic_i8259.pin != i8259_pin)) &&
1393		(i8259_pin >= 0) && (ioapic_i8259.pin >= 0))
1394	{
1395		printk(KERN_WARNING "ExtINT in hardware and MP table differ\n");
1396	}
1397
1398	/*
1399	 * Do not trust the IO-APIC being empty at bootup
1400	 */
1401	clear_IO_APIC();
1402}
1403
1404void native_restore_boot_irq_mode(void)
1405{
1406	/*
1407	 * If the i8259 is routed through an IOAPIC
1408	 * Put that IOAPIC in virtual wire mode
1409	 * so legacy interrupts can be delivered.
1410	 */
1411	if (ioapic_i8259.pin != -1) {
1412		struct IO_APIC_route_entry entry;
 
1413
1414		memset(&entry, 0, sizeof(entry));
1415		entry.mask		= IOAPIC_UNMASKED;
1416		entry.trigger		= IOAPIC_EDGE;
1417		entry.polarity		= IOAPIC_POL_HIGH;
1418		entry.dest_mode		= IOAPIC_DEST_MODE_PHYSICAL;
1419		entry.delivery_mode	= dest_ExtINT;
1420		entry.dest		= read_apic_id();
 
1421
1422		/*
1423		 * Add it to the IO-APIC irq-routing table:
1424		 */
1425		ioapic_write_entry(ioapic_i8259.apic, ioapic_i8259.pin, entry);
1426	}
1427
1428	if (boot_cpu_has(X86_FEATURE_APIC) || apic_from_smp_config())
1429		disconnect_bsp_APIC(ioapic_i8259.pin != -1);
1430}
1431
1432void restore_boot_irq_mode(void)
1433{
1434	if (!nr_legacy_irqs())
1435		return;
1436
1437	x86_apic_ops.restore();
1438}
1439
1440#ifdef CONFIG_X86_32
1441/*
1442 * function to set the IO-APIC physical IDs based on the
1443 * values stored in the MPC table.
1444 *
1445 * by Matt Domsch <Matt_Domsch@dell.com>  Tue Dec 21 12:25:05 CST 1999
1446 */
1447void __init setup_ioapic_ids_from_mpc_nocheck(void)
1448{
 
 
1449	union IO_APIC_reg_00 reg_00;
1450	physid_mask_t phys_id_present_map;
1451	int ioapic_idx;
1452	int i;
1453	unsigned char old_id;
1454	unsigned long flags;
1455
1456	/*
1457	 * This is broken; anything with a real cpu count has to
1458	 * circumvent this idiocy regardless.
1459	 */
1460	apic->ioapic_phys_id_map(&phys_cpu_present_map, &phys_id_present_map);
1461
1462	/*
1463	 * Set the IOAPIC ID to the value stored in the MPC table.
1464	 */
1465	for_each_ioapic(ioapic_idx) {
1466		/* Read the register 0 value */
1467		raw_spin_lock_irqsave(&ioapic_lock, flags);
1468		reg_00.raw = io_apic_read(ioapic_idx, 0);
1469		raw_spin_unlock_irqrestore(&ioapic_lock, flags);
1470
1471		old_id = mpc_ioapic_id(ioapic_idx);
1472
1473		if (mpc_ioapic_id(ioapic_idx) >= get_physical_broadcast()) {
1474			printk(KERN_ERR "BIOS bug, IO-APIC#%d ID is %d in the MPC table!...\n",
1475				ioapic_idx, mpc_ioapic_id(ioapic_idx));
1476			printk(KERN_ERR "... fixing up to %d. (tell your hw vendor)\n",
1477				reg_00.bits.ID);
1478			ioapics[ioapic_idx].mp_config.apicid = reg_00.bits.ID;
1479		}
1480
1481		/*
1482		 * Sanity check, is the ID really free? Every APIC in a
1483		 * system must have a unique ID or we get lots of nice
1484		 * 'stuck on smp_invalidate_needed IPI wait' messages.
1485		 */
1486		if (apic->check_apicid_used(&phys_id_present_map,
1487					    mpc_ioapic_id(ioapic_idx))) {
1488			printk(KERN_ERR "BIOS bug, IO-APIC#%d ID %d is already used!...\n",
1489				ioapic_idx, mpc_ioapic_id(ioapic_idx));
1490			for (i = 0; i < get_physical_broadcast(); i++)
1491				if (!physid_isset(i, phys_id_present_map))
1492					break;
1493			if (i >= get_physical_broadcast())
1494				panic("Max APIC ID exceeded!\n");
1495			printk(KERN_ERR "... fixing up to %d. (tell your hw vendor)\n",
1496				i);
1497			physid_set(i, phys_id_present_map);
1498			ioapics[ioapic_idx].mp_config.apicid = i;
1499		} else {
1500			physid_mask_t tmp;
1501			apic->apicid_to_cpu_present(mpc_ioapic_id(ioapic_idx),
1502						    &tmp);
1503			apic_printk(APIC_VERBOSE, "Setting %d in the "
1504					"phys_id_present_map\n",
1505					mpc_ioapic_id(ioapic_idx));
1506			physids_or(phys_id_present_map, phys_id_present_map, tmp);
1507		}
1508
1509		/*
1510		 * We need to adjust the IRQ routing table
1511		 * if the ID changed.
1512		 */
1513		if (old_id != mpc_ioapic_id(ioapic_idx))
1514			for (i = 0; i < mp_irq_entries; i++)
1515				if (mp_irqs[i].dstapic == old_id)
1516					mp_irqs[i].dstapic
1517						= mpc_ioapic_id(ioapic_idx);
 
1518
1519		/*
1520		 * Update the ID register according to the right value
1521		 * from the MPC table if they are different.
1522		 */
1523		if (mpc_ioapic_id(ioapic_idx) == reg_00.bits.ID)
1524			continue;
1525
1526		apic_printk(APIC_VERBOSE, KERN_INFO
1527			"...changing IO-APIC physical APIC ID to %d ...",
1528			mpc_ioapic_id(ioapic_idx));
1529
1530		reg_00.bits.ID = mpc_ioapic_id(ioapic_idx);
1531		raw_spin_lock_irqsave(&ioapic_lock, flags);
1532		io_apic_write(ioapic_idx, 0, reg_00.raw);
1533		raw_spin_unlock_irqrestore(&ioapic_lock, flags);
1534
1535		/*
1536		 * Sanity check
1537		 */
1538		raw_spin_lock_irqsave(&ioapic_lock, flags);
1539		reg_00.raw = io_apic_read(ioapic_idx, 0);
1540		raw_spin_unlock_irqrestore(&ioapic_lock, flags);
1541		if (reg_00.bits.ID != mpc_ioapic_id(ioapic_idx))
1542			pr_cont("could not set ID!\n");
1543		else
1544			apic_printk(APIC_VERBOSE, " ok.\n");
1545	}
1546}
1547
1548void __init setup_ioapic_ids_from_mpc(void)
1549{
1550
1551	if (acpi_ioapic)
1552		return;
1553	/*
1554	 * Don't check I/O APIC IDs for xAPIC systems.  They have
1555	 * no meaning without the serial APIC bus.
1556	 */
1557	if (!(boot_cpu_data.x86_vendor == X86_VENDOR_INTEL)
1558		|| APIC_XAPIC(boot_cpu_apic_version))
1559		return;
1560	setup_ioapic_ids_from_mpc_nocheck();
1561}
1562#endif
1563
1564int no_timer_check __initdata;
1565
1566static int __init notimercheck(char *s)
1567{
1568	no_timer_check = 1;
1569	return 1;
1570}
1571__setup("no_timer_check", notimercheck);
1572
1573static void __init delay_with_tsc(void)
1574{
1575	unsigned long long start, now;
1576	unsigned long end = jiffies + 4;
1577
1578	start = rdtsc();
1579
1580	/*
1581	 * We don't know the TSC frequency yet, but waiting for
1582	 * 40000000000/HZ TSC cycles is safe:
1583	 * 4 GHz == 10 jiffies
1584	 * 1 GHz == 40 jiffies
1585	 */
1586	do {
1587		rep_nop();
1588		now = rdtsc();
1589	} while ((now - start) < 40000000000ULL / HZ &&
1590		time_before_eq(jiffies, end));
1591}
1592
1593static void __init delay_without_tsc(void)
1594{
1595	unsigned long end = jiffies + 4;
1596	int band = 1;
1597
1598	/*
1599	 * We don't know any frequency yet, but waiting for
1600	 * 40940000000/HZ cycles is safe:
1601	 * 4 GHz == 10 jiffies
1602	 * 1 GHz == 40 jiffies
1603	 * 1 << 1 + 1 << 2 +...+ 1 << 11 = 4094
1604	 */
1605	do {
1606		__delay(((1U << band++) * 10000000UL) / HZ);
1607	} while (band < 12 && time_before_eq(jiffies, end));
1608}
1609
1610/*
1611 * There is a nasty bug in some older SMP boards, their mptable lies
1612 * about the timer IRQ. We do the following to work around the situation:
1613 *
1614 *	- timer IRQ defaults to IO-APIC IRQ
1615 *	- if this function detects that timer IRQs are defunct, then we fall
1616 *	  back to ISA timer IRQs
1617 */
1618static int __init timer_irq_works(void)
1619{
1620	unsigned long t1 = jiffies;
1621	unsigned long flags;
1622
1623	if (no_timer_check)
1624		return 1;
1625
1626	local_save_flags(flags);
1627	local_irq_enable();
1628
1629	if (boot_cpu_has(X86_FEATURE_TSC))
1630		delay_with_tsc();
1631	else
1632		delay_without_tsc();
1633
1634	local_irq_restore(flags);
1635
1636	/*
1637	 * Expect a few ticks at least, to be sure some possible
1638	 * glue logic does not lock up after one or two first
1639	 * ticks in a non-ExtINT mode.  Also the local APIC
1640	 * might have cached one ExtINT interrupt.  Finally, at
1641	 * least one tick may be lost due to delays.
1642	 */
1643
1644	/* jiffies wrap? */
1645	if (time_after(jiffies, t1 + 4))
1646		return 1;
1647	return 0;
1648}
1649
1650/*
1651 * In the SMP+IOAPIC case it might happen that there are an unspecified
1652 * number of pending IRQ events unhandled. These cases are very rare,
1653 * so we 'resend' these IRQs via IPIs, to the same CPU. It's much
1654 * better to do it this way as thus we do not have to be aware of
1655 * 'pending' interrupts in the IRQ path, except at this point.
1656 */
1657/*
1658 * Edge triggered needs to resend any interrupt
1659 * that was delayed but this is now handled in the device
1660 * independent code.
1661 */
1662
1663/*
1664 * Starting up a edge-triggered IO-APIC interrupt is
1665 * nasty - we need to make sure that we get the edge.
1666 * If it is already asserted for some reason, we need
1667 * return 1 to indicate that is was pending.
1668 *
1669 * This is not complete - we should be able to fake
1670 * an edge even if it isn't on the 8259A...
 
 
 
 
 
 
 
 
1671 */
1672static unsigned int startup_ioapic_irq(struct irq_data *data)
1673{
1674	int was_pending = 0, irq = data->irq;
1675	unsigned long flags;
1676
1677	raw_spin_lock_irqsave(&ioapic_lock, flags);
1678	if (irq < nr_legacy_irqs()) {
1679		legacy_pic->mask(irq);
1680		if (legacy_pic->irq_pending(irq))
1681			was_pending = 1;
1682	}
1683	__unmask_ioapic(data->chip_data);
1684	raw_spin_unlock_irqrestore(&ioapic_lock, flags);
1685
1686	return was_pending;
1687}
1688
1689atomic_t irq_mis_count;
1690
1691#ifdef CONFIG_GENERIC_PENDING_IRQ
1692static bool io_apic_level_ack_pending(struct mp_chip_data *data)
1693{
1694	struct irq_pin_list *entry;
1695	unsigned long flags;
1696
1697	raw_spin_lock_irqsave(&ioapic_lock, flags);
1698	for_each_irq_pin(entry, data->irq_2_pin) {
1699		unsigned int reg;
1700		int pin;
1701
1702		pin = entry->pin;
1703		reg = io_apic_read(entry->apic, 0x10 + pin*2);
1704		/* Is the remote IRR bit set? */
1705		if (reg & IO_APIC_REDIR_REMOTE_IRR) {
1706			raw_spin_unlock_irqrestore(&ioapic_lock, flags);
1707			return true;
1708		}
1709	}
1710	raw_spin_unlock_irqrestore(&ioapic_lock, flags);
1711
1712	return false;
1713}
1714
1715static inline bool ioapic_prepare_move(struct irq_data *data)
1716{
1717	/* If we are moving the IRQ we need to mask it */
1718	if (unlikely(irqd_is_setaffinity_pending(data))) {
1719		if (!irqd_irq_masked(data))
1720			mask_ioapic_irq(data);
1721		return true;
1722	}
1723	return false;
1724}
1725
1726static inline void ioapic_finish_move(struct irq_data *data, bool moveit)
1727{
1728	if (unlikely(moveit)) {
1729		/* Only migrate the irq if the ack has been received.
 
1730		 *
1731		 * On rare occasions the broadcast level triggered ack gets
1732		 * delayed going to ioapics, and if we reprogram the
1733		 * vector while Remote IRR is still set the irq will never
1734		 * fire again.
1735		 *
1736		 * To prevent this scenario we read the Remote IRR bit
1737		 * of the ioapic.  This has two effects.
1738		 * - On any sane system the read of the ioapic will
1739		 *   flush writes (and acks) going to the ioapic from
1740		 *   this cpu.
1741		 * - We get to see if the ACK has actually been delivered.
1742		 *
1743		 * Based on failed experiments of reprogramming the
1744		 * ioapic entry from outside of irq context starting
1745		 * with masking the ioapic entry and then polling until
1746		 * Remote IRR was clear before reprogramming the
1747		 * ioapic I don't trust the Remote IRR bit to be
1748		 * completey accurate.
1749		 *
1750		 * However there appears to be no other way to plug
1751		 * this race, so if the Remote IRR bit is not
1752		 * accurate and is causing problems then it is a hardware bug
1753		 * and you can go talk to the chipset vendor about it.
1754		 */
1755		if (!io_apic_level_ack_pending(data->chip_data))
1756			irq_move_masked_irq(data);
1757		/* If the IRQ is masked in the core, leave it: */
1758		if (!irqd_irq_masked(data))
1759			unmask_ioapic_irq(data);
1760	}
1761}
1762#else
1763static inline bool ioapic_prepare_move(struct irq_data *data)
1764{
1765	return false;
1766}
1767static inline void ioapic_finish_move(struct irq_data *data, bool moveit)
1768{
1769}
1770#endif
1771
1772static void ioapic_ack_level(struct irq_data *irq_data)
1773{
1774	struct irq_cfg *cfg = irqd_cfg(irq_data);
1775	unsigned long v;
1776	bool moveit;
1777	int i;
1778
1779	irq_complete_move(cfg);
1780	moveit = ioapic_prepare_move(irq_data);
1781
1782	/*
1783	 * It appears there is an erratum which affects at least version 0x11
1784	 * of I/O APIC (that's the 82093AA and cores integrated into various
1785	 * chipsets).  Under certain conditions a level-triggered interrupt is
1786	 * erroneously delivered as edge-triggered one but the respective IRR
1787	 * bit gets set nevertheless.  As a result the I/O unit expects an EOI
1788	 * message but it will never arrive and further interrupts are blocked
1789	 * from the source.  The exact reason is so far unknown, but the
1790	 * phenomenon was observed when two consecutive interrupt requests
1791	 * from a given source get delivered to the same CPU and the source is
1792	 * temporarily disabled in between.
1793	 *
1794	 * A workaround is to simulate an EOI message manually.  We achieve it
1795	 * by setting the trigger mode to edge and then to level when the edge
1796	 * trigger mode gets detected in the TMR of a local APIC for a
1797	 * level-triggered interrupt.  We mask the source for the time of the
1798	 * operation to prevent an edge-triggered interrupt escaping meanwhile.
1799	 * The idea is from Manfred Spraul.  --macro
1800	 *
1801	 * Also in the case when cpu goes offline, fixup_irqs() will forward
1802	 * any unhandled interrupt on the offlined cpu to the new cpu
1803	 * destination that is handling the corresponding interrupt. This
1804	 * interrupt forwarding is done via IPI's. Hence, in this case also
1805	 * level-triggered io-apic interrupt will be seen as an edge
1806	 * interrupt in the IRR. And we can't rely on the cpu's EOI
1807	 * to be broadcasted to the IO-APIC's which will clear the remoteIRR
1808	 * corresponding to the level-triggered interrupt. Hence on IO-APIC's
1809	 * supporting EOI register, we do an explicit EOI to clear the
1810	 * remote IRR and on IO-APIC's which don't have an EOI register,
1811	 * we use the above logic (mask+edge followed by unmask+level) from
1812	 * Manfred Spraul to clear the remote IRR.
1813	 */
1814	i = cfg->vector;
1815	v = apic_read(APIC_TMR + ((i & ~0x1f) >> 1));
1816
1817	/*
1818	 * We must acknowledge the irq before we move it or the acknowledge will
1819	 * not propagate properly.
1820	 */
1821	ack_APIC_irq();
1822
1823	/*
1824	 * Tail end of clearing remote IRR bit (either by delivering the EOI
1825	 * message via io-apic EOI register write or simulating it using
1826	 * mask+edge followed by unnask+level logic) manually when the
1827	 * level triggered interrupt is seen as the edge triggered interrupt
1828	 * at the cpu.
1829	 */
1830	if (!(v & (1 << (i & 0x1f)))) {
1831		atomic_inc(&irq_mis_count);
1832		eoi_ioapic_pin(cfg->vector, irq_data->chip_data);
1833	}
1834
1835	ioapic_finish_move(irq_data, moveit);
1836}
1837
1838static void ioapic_ir_ack_level(struct irq_data *irq_data)
1839{
1840	struct mp_chip_data *data = irq_data->chip_data;
1841
1842	/*
1843	 * Intr-remapping uses pin number as the virtual vector
1844	 * in the RTE. Actual vector is programmed in
1845	 * intr-remapping table entry. Hence for the io-apic
1846	 * EOI we use the pin number.
1847	 */
1848	apic_ack_irq(irq_data);
1849	eoi_ioapic_pin(data->entry.vector, data);
1850}
1851
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1852static void ioapic_configure_entry(struct irq_data *irqd)
1853{
1854	struct mp_chip_data *mpd = irqd->chip_data;
1855	struct irq_cfg *cfg = irqd_cfg(irqd);
1856	struct irq_pin_list *entry;
1857
1858	/*
1859	 * Only update when the parent is the vector domain, don't touch it
1860	 * if the parent is the remapping domain. Check the installed
1861	 * ioapic chip to verify that.
1862	 */
1863	if (irqd->chip == &ioapic_chip) {
1864		mpd->entry.dest = cfg->dest_apicid;
1865		mpd->entry.vector = cfg->vector;
1866	}
1867	for_each_irq_pin(entry, mpd->irq_2_pin)
1868		__ioapic_write_entry(entry->apic, entry->pin, mpd->entry);
1869}
1870
1871static int ioapic_set_affinity(struct irq_data *irq_data,
1872			       const struct cpumask *mask, bool force)
1873{
1874	struct irq_data *parent = irq_data->parent_data;
1875	unsigned long flags;
1876	int ret;
1877
1878	ret = parent->chip->irq_set_affinity(parent, mask, force);
1879	raw_spin_lock_irqsave(&ioapic_lock, flags);
 
1880	if (ret >= 0 && ret != IRQ_SET_MASK_OK_DONE)
1881		ioapic_configure_entry(irq_data);
1882	raw_spin_unlock_irqrestore(&ioapic_lock, flags);
1883
1884	return ret;
1885}
1886
1887/*
1888 * Interrupt shutdown masks the ioapic pin, but the interrupt might already
1889 * be in flight, but not yet serviced by the target CPU. That means
1890 * __synchronize_hardirq() would return and claim that everything is calmed
1891 * down. So free_irq() would proceed and deactivate the interrupt and free
1892 * resources.
1893 *
1894 * Once the target CPU comes around to service it it will find a cleared
1895 * vector and complain. While the spurious interrupt is harmless, the full
1896 * release of resources might prevent the interrupt from being acknowledged
1897 * which keeps the hardware in a weird state.
1898 *
1899 * Verify that the corresponding Remote-IRR bits are clear.
1900 */
1901static int ioapic_irq_get_chip_state(struct irq_data *irqd,
1902				   enum irqchip_irq_state which,
1903				   bool *state)
1904{
1905	struct mp_chip_data *mcd = irqd->chip_data;
1906	struct IO_APIC_route_entry rentry;
1907	struct irq_pin_list *p;
1908
1909	if (which != IRQCHIP_STATE_ACTIVE)
1910		return -EINVAL;
1911
1912	*state = false;
1913	raw_spin_lock(&ioapic_lock);
 
1914	for_each_irq_pin(p, mcd->irq_2_pin) {
1915		rentry = __ioapic_read_entry(p->apic, p->pin);
1916		/*
1917		 * The remote IRR is only valid in level trigger mode. It's
1918		 * meaning is undefined for edge triggered interrupts and
1919		 * irrelevant because the IO-APIC treats them as fire and
1920		 * forget.
1921		 */
1922		if (rentry.irr && rentry.trigger) {
1923			*state = true;
1924			break;
1925		}
1926	}
1927	raw_spin_unlock(&ioapic_lock);
1928	return 0;
1929}
1930
1931static struct irq_chip ioapic_chip __read_mostly = {
1932	.name			= "IO-APIC",
1933	.irq_startup		= startup_ioapic_irq,
1934	.irq_mask		= mask_ioapic_irq,
1935	.irq_unmask		= unmask_ioapic_irq,
1936	.irq_ack		= irq_chip_ack_parent,
1937	.irq_eoi		= ioapic_ack_level,
1938	.irq_set_affinity	= ioapic_set_affinity,
1939	.irq_retrigger		= irq_chip_retrigger_hierarchy,
1940	.irq_get_irqchip_state	= ioapic_irq_get_chip_state,
1941	.flags			= IRQCHIP_SKIP_SET_WAKE,
 
1942};
1943
1944static struct irq_chip ioapic_ir_chip __read_mostly = {
1945	.name			= "IR-IO-APIC",
1946	.irq_startup		= startup_ioapic_irq,
1947	.irq_mask		= mask_ioapic_irq,
1948	.irq_unmask		= unmask_ioapic_irq,
1949	.irq_ack		= irq_chip_ack_parent,
1950	.irq_eoi		= ioapic_ir_ack_level,
1951	.irq_set_affinity	= ioapic_set_affinity,
1952	.irq_retrigger		= irq_chip_retrigger_hierarchy,
1953	.irq_get_irqchip_state	= ioapic_irq_get_chip_state,
1954	.flags			= IRQCHIP_SKIP_SET_WAKE,
 
1955};
1956
1957static inline void init_IO_APIC_traps(void)
1958{
1959	struct irq_cfg *cfg;
1960	unsigned int irq;
1961
1962	for_each_active_irq(irq) {
1963		cfg = irq_cfg(irq);
1964		if (IO_APIC_IRQ(irq) && cfg && !cfg->vector) {
1965			/*
1966			 * Hmm.. We don't have an entry for this,
1967			 * so default to an old-fashioned 8259
1968			 * interrupt if we can..
1969			 */
1970			if (irq < nr_legacy_irqs())
1971				legacy_pic->make_irq(irq);
1972			else
1973				/* Strange. Oh, well.. */
1974				irq_set_chip(irq, &no_irq_chip);
1975		}
1976	}
1977}
1978
1979/*
1980 * The local APIC irq-chip implementation:
1981 */
1982
1983static void mask_lapic_irq(struct irq_data *data)
1984{
1985	unsigned long v;
1986
1987	v = apic_read(APIC_LVT0);
1988	apic_write(APIC_LVT0, v | APIC_LVT_MASKED);
1989}
1990
1991static void unmask_lapic_irq(struct irq_data *data)
1992{
1993	unsigned long v;
1994
1995	v = apic_read(APIC_LVT0);
1996	apic_write(APIC_LVT0, v & ~APIC_LVT_MASKED);
1997}
1998
1999static void ack_lapic_irq(struct irq_data *data)
2000{
2001	ack_APIC_irq();
2002}
2003
2004static struct irq_chip lapic_chip __read_mostly = {
2005	.name		= "local-APIC",
2006	.irq_mask	= mask_lapic_irq,
2007	.irq_unmask	= unmask_lapic_irq,
2008	.irq_ack	= ack_lapic_irq,
2009};
2010
2011static void lapic_register_intr(int irq)
2012{
2013	irq_clear_status_flags(irq, IRQ_LEVEL);
2014	irq_set_chip_and_handler_name(irq, &lapic_chip, handle_edge_irq,
2015				      "edge");
2016}
2017
2018/*
2019 * This looks a bit hackish but it's about the only one way of sending
2020 * a few INTA cycles to 8259As and any associated glue logic.  ICR does
2021 * not support the ExtINT mode, unfortunately.  We need to send these
2022 * cycles as some i82489DX-based boards have glue logic that keeps the
2023 * 8259A interrupt line asserted until INTA.  --macro
2024 */
2025static inline void __init unlock_ExtINT_logic(void)
2026{
 
 
2027	int apic, pin, i;
2028	struct IO_APIC_route_entry entry0, entry1;
2029	unsigned char save_control, save_freq_select;
2030
2031	pin  = find_isa_irq_pin(8, mp_INT);
2032	if (pin == -1) {
2033		WARN_ON_ONCE(1);
2034		return;
2035	}
2036	apic = find_isa_irq_apic(8, mp_INT);
2037	if (apic == -1) {
2038		WARN_ON_ONCE(1);
2039		return;
2040	}
2041
2042	entry0 = ioapic_read_entry(apic, pin);
2043	clear_IO_APIC_pin(apic, pin);
2044
 
2045	memset(&entry1, 0, sizeof(entry1));
2046
2047	entry1.dest_mode = IOAPIC_DEST_MODE_PHYSICAL;
2048	entry1.mask = IOAPIC_UNMASKED;
2049	entry1.dest = hard_smp_processor_id();
2050	entry1.delivery_mode = dest_ExtINT;
2051	entry1.polarity = entry0.polarity;
2052	entry1.trigger = IOAPIC_EDGE;
 
2053	entry1.vector = 0;
2054
2055	ioapic_write_entry(apic, pin, entry1);
2056
2057	save_control = CMOS_READ(RTC_CONTROL);
2058	save_freq_select = CMOS_READ(RTC_FREQ_SELECT);
2059	CMOS_WRITE((save_freq_select & ~RTC_RATE_SELECT) | 0x6,
2060		   RTC_FREQ_SELECT);
2061	CMOS_WRITE(save_control | RTC_PIE, RTC_CONTROL);
2062
2063	i = 100;
2064	while (i-- > 0) {
2065		mdelay(10);
2066		if ((CMOS_READ(RTC_INTR_FLAGS) & RTC_PF) == RTC_PF)
2067			i -= 10;
2068	}
2069
2070	CMOS_WRITE(save_control, RTC_CONTROL);
2071	CMOS_WRITE(save_freq_select, RTC_FREQ_SELECT);
2072	clear_IO_APIC_pin(apic, pin);
2073
2074	ioapic_write_entry(apic, pin, entry0);
2075}
2076
2077static int disable_timer_pin_1 __initdata;
2078/* Actually the next is obsolete, but keep it for paranoid reasons -AK */
2079static int __init disable_timer_pin_setup(char *arg)
2080{
2081	disable_timer_pin_1 = 1;
2082	return 0;
2083}
2084early_param("disable_timer_pin_1", disable_timer_pin_setup);
2085
2086static int mp_alloc_timer_irq(int ioapic, int pin)
2087{
 
2088	int irq = -1;
2089	struct irq_domain *domain = mp_ioapic_irqdomain(ioapic);
2090
2091	if (domain) {
2092		struct irq_alloc_info info;
2093
2094		ioapic_set_alloc_attr(&info, NUMA_NO_NODE, 0, 0);
2095		info.ioapic_id = mpc_ioapic_id(ioapic);
2096		info.ioapic_pin = pin;
2097		mutex_lock(&ioapic_mutex);
2098		irq = alloc_isa_irq_from_domain(domain, 0, ioapic, pin, &info);
2099		mutex_unlock(&ioapic_mutex);
2100	}
2101
2102	return irq;
2103}
2104
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2105/*
2106 * This code may look a bit paranoid, but it's supposed to cooperate with
2107 * a wide range of boards and BIOS bugs.  Fortunately only the timer IRQ
2108 * is so screwy.  Thanks to Brian Perkins for testing/hacking this beast
2109 * fanatically on his truly buggy board.
2110 *
2111 * FIXME: really need to revamp this for all platforms.
2112 */
2113static inline void __init check_timer(void)
2114{
2115	struct irq_data *irq_data = irq_get_irq_data(0);
2116	struct mp_chip_data *data = irq_data->chip_data;
2117	struct irq_cfg *cfg = irqd_cfg(irq_data);
2118	int node = cpu_to_node(0);
2119	int apic1, pin1, apic2, pin2;
2120	unsigned long flags;
2121	int no_pin1 = 0;
2122
2123	if (!global_clock_event)
2124		return;
2125
2126	local_irq_save(flags);
2127
2128	/*
2129	 * get/set the timer IRQ vector:
2130	 */
2131	legacy_pic->mask(0);
2132
2133	/*
2134	 * As IRQ0 is to be enabled in the 8259A, the virtual
2135	 * wire has to be disabled in the local APIC.  Also
2136	 * timer interrupts need to be acknowledged manually in
2137	 * the 8259A for the i82489DX when using the NMI
2138	 * watchdog as that APIC treats NMIs as level-triggered.
2139	 * The AEOI mode will finish them in the 8259A
2140	 * automatically.
2141	 */
2142	apic_write(APIC_LVT0, APIC_LVT_MASKED | APIC_DM_EXTINT);
2143	legacy_pic->init(1);
2144
2145	pin1  = find_isa_irq_pin(0, mp_INT);
2146	apic1 = find_isa_irq_apic(0, mp_INT);
2147	pin2  = ioapic_i8259.pin;
2148	apic2 = ioapic_i8259.apic;
2149
2150	apic_printk(APIC_QUIET, KERN_INFO "..TIMER: vector=0x%02X "
2151		    "apic1=%d pin1=%d apic2=%d pin2=%d\n",
2152		    cfg->vector, apic1, pin1, apic2, pin2);
2153
2154	/*
2155	 * Some BIOS writers are clueless and report the ExtINTA
2156	 * I/O APIC input from the cascaded 8259A as the timer
2157	 * interrupt input.  So just in case, if only one pin
2158	 * was found above, try it both directly and through the
2159	 * 8259A.
2160	 */
2161	if (pin1 == -1) {
2162		panic_if_irq_remap("BIOS bug: timer not connected to IO-APIC");
2163		pin1 = pin2;
2164		apic1 = apic2;
2165		no_pin1 = 1;
2166	} else if (pin2 == -1) {
2167		pin2 = pin1;
2168		apic2 = apic1;
2169	}
2170
2171	if (pin1 != -1) {
2172		/* Ok, does IRQ0 through the IOAPIC work? */
2173		if (no_pin1) {
2174			mp_alloc_timer_irq(apic1, pin1);
2175		} else {
2176			/*
2177			 * for edge trigger, it's already unmasked,
2178			 * so only need to unmask if it is level-trigger
2179			 * do we really have level trigger timer?
2180			 */
2181			int idx;
2182			idx = find_irq_entry(apic1, pin1, mp_INT);
2183			if (idx != -1 && irq_trigger(idx))
2184				unmask_ioapic_irq(irq_get_irq_data(0));
2185		}
2186		irq_domain_deactivate_irq(irq_data);
2187		irq_domain_activate_irq(irq_data, false);
2188		if (timer_irq_works()) {
2189			if (disable_timer_pin_1 > 0)
2190				clear_IO_APIC_pin(0, pin1);
2191			goto out;
2192		}
2193		panic_if_irq_remap("timer doesn't work through Interrupt-remapped IO-APIC");
2194		local_irq_disable();
2195		clear_IO_APIC_pin(apic1, pin1);
2196		if (!no_pin1)
2197			apic_printk(APIC_QUIET, KERN_ERR "..MP-BIOS bug: "
2198				    "8254 timer not connected to IO-APIC\n");
2199
2200		apic_printk(APIC_QUIET, KERN_INFO "...trying to set up timer "
2201			    "(IRQ0) through the 8259A ...\n");
2202		apic_printk(APIC_QUIET, KERN_INFO
2203			    "..... (found apic %d pin %d) ...\n", apic2, pin2);
2204		/*
2205		 * legacy devices should be connected to IO APIC #0
2206		 */
2207		replace_pin_at_irq_node(data, node, apic1, pin1, apic2, pin2);
2208		irq_domain_deactivate_irq(irq_data);
2209		irq_domain_activate_irq(irq_data, false);
2210		legacy_pic->unmask(0);
2211		if (timer_irq_works()) {
2212			apic_printk(APIC_QUIET, KERN_INFO "....... works.\n");
2213			goto out;
2214		}
2215		/*
2216		 * Cleanup, just in case ...
2217		 */
2218		local_irq_disable();
2219		legacy_pic->mask(0);
2220		clear_IO_APIC_pin(apic2, pin2);
2221		apic_printk(APIC_QUIET, KERN_INFO "....... failed.\n");
2222	}
2223
2224	apic_printk(APIC_QUIET, KERN_INFO
2225		    "...trying to set up timer as Virtual Wire IRQ...\n");
2226
2227	lapic_register_intr(0);
2228	apic_write(APIC_LVT0, APIC_DM_FIXED | cfg->vector);	/* Fixed mode */
2229	legacy_pic->unmask(0);
2230
2231	if (timer_irq_works()) {
2232		apic_printk(APIC_QUIET, KERN_INFO "..... works.\n");
2233		goto out;
2234	}
2235	local_irq_disable();
2236	legacy_pic->mask(0);
2237	apic_write(APIC_LVT0, APIC_LVT_MASKED | APIC_DM_FIXED | cfg->vector);
2238	apic_printk(APIC_QUIET, KERN_INFO "..... failed.\n");
2239
2240	apic_printk(APIC_QUIET, KERN_INFO
2241		    "...trying to set up timer as ExtINT IRQ...\n");
2242
2243	legacy_pic->init(0);
2244	legacy_pic->make_irq(0);
2245	apic_write(APIC_LVT0, APIC_DM_EXTINT);
2246	legacy_pic->unmask(0);
2247
2248	unlock_ExtINT_logic();
2249
2250	if (timer_irq_works()) {
2251		apic_printk(APIC_QUIET, KERN_INFO "..... works.\n");
2252		goto out;
2253	}
2254	local_irq_disable();
2255	apic_printk(APIC_QUIET, KERN_INFO "..... failed :(.\n");
2256	if (apic_is_x2apic_enabled())
2257		apic_printk(APIC_QUIET, KERN_INFO
2258			    "Perhaps problem with the pre-enabled x2apic mode\n"
2259			    "Try booting with x2apic and interrupt-remapping disabled in the bios.\n");
2260	panic("IO-APIC + timer doesn't work!  Boot with apic=debug and send a "
2261		"report.  Then try booting with the 'noapic' option.\n");
2262out:
2263	local_irq_restore(flags);
2264}
2265
2266/*
2267 * Traditionally ISA IRQ2 is the cascade IRQ, and is not available
2268 * to devices.  However there may be an I/O APIC pin available for
2269 * this interrupt regardless.  The pin may be left unconnected, but
2270 * typically it will be reused as an ExtINT cascade interrupt for
2271 * the master 8259A.  In the MPS case such a pin will normally be
2272 * reported as an ExtINT interrupt in the MP table.  With ACPI
2273 * there is no provision for ExtINT interrupts, and in the absence
2274 * of an override it would be treated as an ordinary ISA I/O APIC
2275 * interrupt, that is edge-triggered and unmasked by default.  We
2276 * used to do this, but it caused problems on some systems because
2277 * of the NMI watchdog and sometimes IRQ0 of the 8254 timer using
2278 * the same ExtINT cascade interrupt to drive the local APIC of the
2279 * bootstrap processor.  Therefore we refrain from routing IRQ2 to
2280 * the I/O APIC in all cases now.  No actual device should request
2281 * it anyway.  --macro
2282 */
2283#define PIC_IRQS	(1UL << PIC_CASCADE_IR)
2284
2285static int mp_irqdomain_create(int ioapic)
2286{
2287	struct irq_alloc_info info;
2288	struct irq_domain *parent;
2289	int hwirqs = mp_ioapic_pin_count(ioapic);
2290	struct ioapic *ip = &ioapics[ioapic];
2291	struct ioapic_domain_cfg *cfg = &ip->irqdomain_cfg;
2292	struct mp_ioapic_gsi *gsi_cfg = mp_ioapic_gsi_routing(ioapic);
2293	struct fwnode_handle *fn;
2294	char *name = "IO-APIC";
2295
2296	if (cfg->type == IOAPIC_DOMAIN_INVALID)
2297		return 0;
2298
2299	init_irq_alloc_info(&info, NULL);
2300	info.type = X86_IRQ_ALLOC_TYPE_IOAPIC;
2301	info.ioapic_id = mpc_ioapic_id(ioapic);
2302	parent = irq_remapping_get_ir_irq_domain(&info);
2303	if (!parent)
2304		parent = x86_vector_domain;
2305	else
2306		name = "IO-APIC-IR";
2307
2308	/* Handle device tree enumerated APICs proper */
2309	if (cfg->dev) {
2310		fn = of_node_to_fwnode(cfg->dev);
2311	} else {
2312		fn = irq_domain_alloc_named_id_fwnode(name, ioapic);
2313		if (!fn)
2314			return -ENOMEM;
2315	}
2316
2317	ip->irqdomain = irq_domain_create_linear(fn, hwirqs, cfg->ops,
2318						 (void *)(long)ioapic);
 
 
 
 
 
 
 
 
2319
 
 
2320	if (!ip->irqdomain) {
2321		/* Release fw handle if it was allocated above */
2322		if (!cfg->dev)
2323			irq_domain_free_fwnode(fn);
2324		return -ENOMEM;
2325	}
2326
2327	ip->irqdomain->parent = parent;
2328
2329	if (cfg->type == IOAPIC_DOMAIN_LEGACY ||
2330	    cfg->type == IOAPIC_DOMAIN_STRICT)
2331		ioapic_dynirq_base = max(ioapic_dynirq_base,
2332					 gsi_cfg->gsi_end + 1);
2333
2334	return 0;
2335}
2336
2337static void ioapic_destroy_irqdomain(int idx)
2338{
2339	struct ioapic_domain_cfg *cfg = &ioapics[idx].irqdomain_cfg;
2340	struct fwnode_handle *fn = ioapics[idx].irqdomain->fwnode;
2341
2342	if (ioapics[idx].irqdomain) {
2343		irq_domain_remove(ioapics[idx].irqdomain);
2344		if (!cfg->dev)
2345			irq_domain_free_fwnode(fn);
2346		ioapics[idx].irqdomain = NULL;
2347	}
2348}
2349
2350void __init setup_IO_APIC(void)
2351{
2352	int ioapic;
2353
2354	if (skip_ioapic_setup || !nr_ioapics)
2355		return;
2356
2357	io_apic_irqs = nr_legacy_irqs() ? ~PIC_IRQS : ~0UL;
2358
2359	apic_printk(APIC_VERBOSE, "ENABLING IO-APIC IRQs\n");
2360	for_each_ioapic(ioapic)
2361		BUG_ON(mp_irqdomain_create(ioapic));
2362
2363	/*
2364         * Set up IO-APIC IRQ routing.
2365         */
2366	x86_init.mpparse.setup_ioapic_ids();
2367
2368	sync_Arb_IDs();
2369	setup_IO_APIC_irqs();
2370	init_IO_APIC_traps();
2371	if (nr_legacy_irqs())
2372		check_timer();
2373
2374	ioapic_initialized = 1;
2375}
2376
2377static void resume_ioapic_id(int ioapic_idx)
2378{
2379	unsigned long flags;
2380	union IO_APIC_reg_00 reg_00;
2381
2382	raw_spin_lock_irqsave(&ioapic_lock, flags);
2383	reg_00.raw = io_apic_read(ioapic_idx, 0);
2384	if (reg_00.bits.ID != mpc_ioapic_id(ioapic_idx)) {
2385		reg_00.bits.ID = mpc_ioapic_id(ioapic_idx);
2386		io_apic_write(ioapic_idx, 0, reg_00.raw);
2387	}
2388	raw_spin_unlock_irqrestore(&ioapic_lock, flags);
2389}
2390
2391static void ioapic_resume(void)
2392{
2393	int ioapic_idx;
2394
2395	for_each_ioapic_reverse(ioapic_idx)
2396		resume_ioapic_id(ioapic_idx);
2397
2398	restore_ioapic_entries();
2399}
2400
2401static struct syscore_ops ioapic_syscore_ops = {
2402	.suspend = save_ioapic_entries,
2403	.resume = ioapic_resume,
2404};
2405
2406static int __init ioapic_init_ops(void)
2407{
2408	register_syscore_ops(&ioapic_syscore_ops);
2409
2410	return 0;
2411}
2412
2413device_initcall(ioapic_init_ops);
2414
2415static int io_apic_get_redir_entries(int ioapic)
2416{
2417	union IO_APIC_reg_01	reg_01;
2418	unsigned long flags;
2419
2420	raw_spin_lock_irqsave(&ioapic_lock, flags);
2421	reg_01.raw = io_apic_read(ioapic, 1);
2422	raw_spin_unlock_irqrestore(&ioapic_lock, flags);
2423
2424	/* The register returns the maximum index redir index
2425	 * supported, which is one less than the total number of redir
2426	 * entries.
2427	 */
2428	return reg_01.bits.entries + 1;
2429}
2430
2431unsigned int arch_dynirq_lower_bound(unsigned int from)
2432{
 
 
2433	/*
2434	 * dmar_alloc_hwirq() may be called before setup_IO_APIC(), so use
2435	 * gsi_top if ioapic_dynirq_base hasn't been initialized yet.
2436	 */
2437	if (!ioapic_initialized)
2438		return gsi_top;
2439	/*
2440	 * For DT enabled machines ioapic_dynirq_base is irrelevant and not
2441	 * updated. So simply return @from if ioapic_dynirq_base == 0.
 
 
2442	 */
2443	return ioapic_dynirq_base ? : from;
2444}
2445
2446#ifdef CONFIG_X86_32
2447static int io_apic_get_unique_id(int ioapic, int apic_id)
2448{
 
 
2449	union IO_APIC_reg_00 reg_00;
2450	static physid_mask_t apic_id_map = PHYSID_MASK_NONE;
2451	physid_mask_t tmp;
2452	unsigned long flags;
2453	int i = 0;
2454
2455	/*
2456	 * The P4 platform supports up to 256 APIC IDs on two separate APIC
2457	 * buses (one for LAPICs, one for IOAPICs), where predecessors only
2458	 * supports up to 16 on one shared APIC bus.
2459	 *
2460	 * TBD: Expand LAPIC/IOAPIC support on P4-class systems to take full
2461	 *      advantage of new APIC bus architecture.
2462	 */
2463
2464	if (physids_empty(apic_id_map))
2465		apic->ioapic_phys_id_map(&phys_cpu_present_map, &apic_id_map);
2466
2467	raw_spin_lock_irqsave(&ioapic_lock, flags);
2468	reg_00.raw = io_apic_read(ioapic, 0);
2469	raw_spin_unlock_irqrestore(&ioapic_lock, flags);
2470
2471	if (apic_id >= get_physical_broadcast()) {
2472		printk(KERN_WARNING "IOAPIC[%d]: Invalid apic_id %d, trying "
2473			"%d\n", ioapic, apic_id, reg_00.bits.ID);
2474		apic_id = reg_00.bits.ID;
2475	}
2476
2477	/*
2478	 * Every APIC in a system must have a unique ID or we get lots of nice
2479	 * 'stuck on smp_invalidate_needed IPI wait' messages.
2480	 */
2481	if (apic->check_apicid_used(&apic_id_map, apic_id)) {
2482
2483		for (i = 0; i < get_physical_broadcast(); i++) {
2484			if (!apic->check_apicid_used(&apic_id_map, i))
2485				break;
2486		}
2487
2488		if (i == get_physical_broadcast())
2489			panic("Max apic_id exceeded!\n");
2490
2491		printk(KERN_WARNING "IOAPIC[%d]: apic_id %d already used, "
2492			"trying %d\n", ioapic, apic_id, i);
2493
2494		apic_id = i;
2495	}
2496
2497	apic->apicid_to_cpu_present(apic_id, &tmp);
2498	physids_or(apic_id_map, apic_id_map, tmp);
2499
2500	if (reg_00.bits.ID != apic_id) {
2501		reg_00.bits.ID = apic_id;
2502
2503		raw_spin_lock_irqsave(&ioapic_lock, flags);
2504		io_apic_write(ioapic, 0, reg_00.raw);
2505		reg_00.raw = io_apic_read(ioapic, 0);
2506		raw_spin_unlock_irqrestore(&ioapic_lock, flags);
2507
2508		/* Sanity check */
2509		if (reg_00.bits.ID != apic_id) {
2510			pr_err("IOAPIC[%d]: Unable to change apic_id!\n",
2511			       ioapic);
2512			return -1;
2513		}
2514	}
2515
2516	apic_printk(APIC_VERBOSE, KERN_INFO
2517			"IOAPIC[%d]: Assigned apic_id %d\n", ioapic, apic_id);
2518
2519	return apic_id;
2520}
2521
2522static u8 io_apic_unique_id(int idx, u8 id)
2523{
2524	if ((boot_cpu_data.x86_vendor == X86_VENDOR_INTEL) &&
2525	    !APIC_XAPIC(boot_cpu_apic_version))
2526		return io_apic_get_unique_id(idx, id);
2527	else
2528		return id;
2529}
2530#else
2531static u8 io_apic_unique_id(int idx, u8 id)
2532{
2533	union IO_APIC_reg_00 reg_00;
2534	DECLARE_BITMAP(used, 256);
2535	unsigned long flags;
2536	u8 new_id;
2537	int i;
2538
2539	bitmap_zero(used, 256);
2540	for_each_ioapic(i)
2541		__set_bit(mpc_ioapic_id(i), used);
2542
2543	/* Hand out the requested id if available */
2544	if (!test_bit(id, used))
2545		return id;
2546
2547	/*
2548	 * Read the current id from the ioapic and keep it if
2549	 * available.
2550	 */
2551	raw_spin_lock_irqsave(&ioapic_lock, flags);
2552	reg_00.raw = io_apic_read(idx, 0);
2553	raw_spin_unlock_irqrestore(&ioapic_lock, flags);
2554	new_id = reg_00.bits.ID;
2555	if (!test_bit(new_id, used)) {
2556		apic_printk(APIC_VERBOSE, KERN_INFO
2557			"IOAPIC[%d]: Using reg apic_id %d instead of %d\n",
2558			 idx, new_id, id);
2559		return new_id;
2560	}
2561
2562	/*
2563	 * Get the next free id and write it to the ioapic.
2564	 */
2565	new_id = find_first_zero_bit(used, 256);
2566	reg_00.bits.ID = new_id;
2567	raw_spin_lock_irqsave(&ioapic_lock, flags);
2568	io_apic_write(idx, 0, reg_00.raw);
2569	reg_00.raw = io_apic_read(idx, 0);
2570	raw_spin_unlock_irqrestore(&ioapic_lock, flags);
2571	/* Sanity check */
2572	BUG_ON(reg_00.bits.ID != new_id);
2573
2574	return new_id;
2575}
2576#endif
2577
2578static int io_apic_get_version(int ioapic)
2579{
2580	union IO_APIC_reg_01	reg_01;
2581	unsigned long flags;
2582
2583	raw_spin_lock_irqsave(&ioapic_lock, flags);
2584	reg_01.raw = io_apic_read(ioapic, 1);
2585	raw_spin_unlock_irqrestore(&ioapic_lock, flags);
2586
2587	return reg_01.bits.version;
2588}
2589
2590int acpi_get_override_irq(u32 gsi, int *trigger, int *polarity)
2591{
2592	int ioapic, pin, idx;
2593
2594	if (skip_ioapic_setup)
2595		return -1;
2596
2597	ioapic = mp_find_ioapic(gsi);
2598	if (ioapic < 0)
2599		return -1;
2600
2601	pin = mp_find_ioapic_pin(ioapic, gsi);
2602	if (pin < 0)
2603		return -1;
2604
2605	idx = find_irq_entry(ioapic, pin, mp_INT);
2606	if (idx < 0)
2607		return -1;
2608
2609	*trigger = irq_trigger(idx);
2610	*polarity = irq_polarity(idx);
2611	return 0;
2612}
2613
2614/*
2615 * This function updates target affinity of IOAPIC interrupts to include
2616 * the CPUs which came online during SMP bringup.
2617 */
2618#define IOAPIC_RESOURCE_NAME_SIZE 11
2619
2620static struct resource *ioapic_resources;
2621
2622static struct resource * __init ioapic_setup_resources(void)
2623{
 
2624	unsigned long n;
2625	struct resource *res;
2626	char *mem;
2627	int i;
2628
2629	if (nr_ioapics == 0)
2630		return NULL;
2631
2632	n = IOAPIC_RESOURCE_NAME_SIZE + sizeof(struct resource);
2633	n *= nr_ioapics;
2634
2635	mem = memblock_alloc(n, SMP_CACHE_BYTES);
2636	if (!mem)
2637		panic("%s: Failed to allocate %lu bytes\n", __func__, n);
2638	res = (void *)mem;
2639
2640	mem += sizeof(struct resource) * nr_ioapics;
2641
2642	for_each_ioapic(i) {
2643		res[i].name = mem;
2644		res[i].flags = IORESOURCE_MEM | IORESOURCE_BUSY;
2645		snprintf(mem, IOAPIC_RESOURCE_NAME_SIZE, "IOAPIC %u", i);
2646		mem += IOAPIC_RESOURCE_NAME_SIZE;
2647		ioapics[i].iomem_res = &res[i];
2648	}
2649
2650	ioapic_resources = res;
2651
2652	return res;
2653}
2654
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2655void __init io_apic_init_mappings(void)
2656{
2657	unsigned long ioapic_phys, idx = FIX_IO_APIC_BASE_0;
2658	struct resource *ioapic_res;
2659	int i;
2660
2661	ioapic_res = ioapic_setup_resources();
2662	for_each_ioapic(i) {
2663		if (smp_found_config) {
2664			ioapic_phys = mpc_ioapic_addr(i);
2665#ifdef CONFIG_X86_32
2666			if (!ioapic_phys) {
2667				printk(KERN_ERR
2668				       "WARNING: bogus zero IO-APIC "
2669				       "address found in MPTABLE, "
2670				       "disabling IO/APIC support!\n");
2671				smp_found_config = 0;
2672				skip_ioapic_setup = 1;
2673				goto fake_ioapic_page;
2674			}
2675#endif
2676		} else {
2677#ifdef CONFIG_X86_32
2678fake_ioapic_page:
2679#endif
2680			ioapic_phys = (unsigned long)memblock_alloc(PAGE_SIZE,
2681								    PAGE_SIZE);
2682			if (!ioapic_phys)
2683				panic("%s: Failed to allocate %lu bytes align=0x%lx\n",
2684				      __func__, PAGE_SIZE, PAGE_SIZE);
2685			ioapic_phys = __pa(ioapic_phys);
2686		}
2687		set_fixmap_nocache(idx, ioapic_phys);
2688		apic_printk(APIC_VERBOSE, "mapped IOAPIC to %08lx (%08lx)\n",
2689			__fix_to_virt(idx) + (ioapic_phys & ~PAGE_MASK),
2690			ioapic_phys);
2691		idx++;
2692
2693		ioapic_res->start = ioapic_phys;
2694		ioapic_res->end = ioapic_phys + IO_APIC_SLOT_SIZE - 1;
2695		ioapic_res++;
2696	}
2697}
2698
2699void __init ioapic_insert_resources(void)
2700{
 
2701	int i;
2702	struct resource *r = ioapic_resources;
2703
2704	if (!r) {
2705		if (nr_ioapics > 0)
2706			printk(KERN_ERR
2707				"IO APIC resources couldn't be allocated.\n");
2708		return;
2709	}
2710
2711	for_each_ioapic(i) {
2712		insert_resource(&iomem_resource, r);
2713		r++;
2714	}
2715}
2716
2717int mp_find_ioapic(u32 gsi)
2718{
2719	int i;
2720
2721	if (nr_ioapics == 0)
2722		return -1;
2723
2724	/* Find the IOAPIC that manages this GSI. */
2725	for_each_ioapic(i) {
2726		struct mp_ioapic_gsi *gsi_cfg = mp_ioapic_gsi_routing(i);
 
2727		if (gsi >= gsi_cfg->gsi_base && gsi <= gsi_cfg->gsi_end)
2728			return i;
2729	}
2730
2731	printk(KERN_ERR "ERROR: Unable to locate IOAPIC for GSI %d\n", gsi);
2732	return -1;
2733}
2734
2735int mp_find_ioapic_pin(int ioapic, u32 gsi)
2736{
2737	struct mp_ioapic_gsi *gsi_cfg;
2738
2739	if (WARN_ON(ioapic < 0))
2740		return -1;
2741
2742	gsi_cfg = mp_ioapic_gsi_routing(ioapic);
2743	if (WARN_ON(gsi > gsi_cfg->gsi_end))
2744		return -1;
2745
2746	return gsi - gsi_cfg->gsi_base;
2747}
2748
2749static int bad_ioapic_register(int idx)
2750{
2751	union IO_APIC_reg_00 reg_00;
2752	union IO_APIC_reg_01 reg_01;
2753	union IO_APIC_reg_02 reg_02;
2754
2755	reg_00.raw = io_apic_read(idx, 0);
2756	reg_01.raw = io_apic_read(idx, 1);
2757	reg_02.raw = io_apic_read(idx, 2);
2758
2759	if (reg_00.raw == -1 && reg_01.raw == -1 && reg_02.raw == -1) {
2760		pr_warn("I/O APIC 0x%x registers return all ones, skipping!\n",
2761			mpc_ioapic_addr(idx));
2762		return 1;
2763	}
2764
2765	return 0;
2766}
2767
2768static int find_free_ioapic_entry(void)
2769{
2770	int idx;
2771
2772	for (idx = 0; idx < MAX_IO_APICS; idx++)
2773		if (ioapics[idx].nr_registers == 0)
2774			return idx;
2775
2776	return MAX_IO_APICS;
2777}
2778
2779/**
2780 * mp_register_ioapic - Register an IOAPIC device
2781 * @id:		hardware IOAPIC ID
2782 * @address:	physical address of IOAPIC register area
2783 * @gsi_base:	base of GSI associated with the IOAPIC
2784 * @cfg:	configuration information for the IOAPIC
2785 */
2786int mp_register_ioapic(int id, u32 address, u32 gsi_base,
2787		       struct ioapic_domain_cfg *cfg)
2788{
2789	bool hotplug = !!ioapic_initialized;
2790	struct mp_ioapic_gsi *gsi_cfg;
2791	int idx, ioapic, entries;
2792	u32 gsi_end;
2793
2794	if (!address) {
2795		pr_warn("Bogus (zero) I/O APIC address found, skipping!\n");
2796		return -EINVAL;
2797	}
2798	for_each_ioapic(ioapic)
 
2799		if (ioapics[ioapic].mp_config.apicaddr == address) {
2800			pr_warn("address 0x%x conflicts with IOAPIC%d\n",
2801				address, ioapic);
2802			return -EEXIST;
2803		}
 
2804
2805	idx = find_free_ioapic_entry();
2806	if (idx >= MAX_IO_APICS) {
2807		pr_warn("Max # of I/O APICs (%d) exceeded (found %d), skipping\n",
2808			MAX_IO_APICS, idx);
2809		return -ENOSPC;
2810	}
2811
2812	ioapics[idx].mp_config.type = MP_IOAPIC;
2813	ioapics[idx].mp_config.flags = MPC_APIC_USABLE;
2814	ioapics[idx].mp_config.apicaddr = address;
2815
2816	set_fixmap_nocache(FIX_IO_APIC_BASE_0 + idx, address);
2817	if (bad_ioapic_register(idx)) {
2818		clear_fixmap(FIX_IO_APIC_BASE_0 + idx);
2819		return -ENODEV;
2820	}
2821
2822	ioapics[idx].mp_config.apicid = io_apic_unique_id(idx, id);
2823	ioapics[idx].mp_config.apicver = io_apic_get_version(idx);
2824
2825	/*
2826	 * Build basic GSI lookup table to facilitate gsi->io_apic lookups
2827	 * and to prevent reprogramming of IOAPIC pins (PCI GSIs).
2828	 */
2829	entries = io_apic_get_redir_entries(idx);
2830	gsi_end = gsi_base + entries - 1;
2831	for_each_ioapic(ioapic) {
2832		gsi_cfg = mp_ioapic_gsi_routing(ioapic);
2833		if ((gsi_base >= gsi_cfg->gsi_base &&
2834		     gsi_base <= gsi_cfg->gsi_end) ||
2835		    (gsi_end >= gsi_cfg->gsi_base &&
2836		     gsi_end <= gsi_cfg->gsi_end)) {
2837			pr_warn("GSI range [%u-%u] for new IOAPIC conflicts with GSI[%u-%u]\n",
2838				gsi_base, gsi_end,
2839				gsi_cfg->gsi_base, gsi_cfg->gsi_end);
2840			clear_fixmap(FIX_IO_APIC_BASE_0 + idx);
2841			return -ENOSPC;
2842		}
2843	}
2844	gsi_cfg = mp_ioapic_gsi_routing(idx);
2845	gsi_cfg->gsi_base = gsi_base;
2846	gsi_cfg->gsi_end = gsi_end;
2847
2848	ioapics[idx].irqdomain = NULL;
2849	ioapics[idx].irqdomain_cfg = *cfg;
2850
2851	/*
2852	 * If mp_register_ioapic() is called during early boot stage when
2853	 * walking ACPI/SFI/DT tables, it's too early to create irqdomain,
2854	 * we are still using bootmem allocator. So delay it to setup_IO_APIC().
2855	 */
2856	if (hotplug) {
2857		if (mp_irqdomain_create(idx)) {
2858			clear_fixmap(FIX_IO_APIC_BASE_0 + idx);
2859			return -ENOMEM;
2860		}
2861		alloc_ioapic_saved_registers(idx);
2862	}
2863
2864	if (gsi_cfg->gsi_end >= gsi_top)
2865		gsi_top = gsi_cfg->gsi_end + 1;
2866	if (nr_ioapics <= idx)
2867		nr_ioapics = idx + 1;
2868
2869	/* Set nr_registers to mark entry present */
2870	ioapics[idx].nr_registers = entries;
2871
2872	pr_info("IOAPIC[%d]: apic_id %d, version %d, address 0x%x, GSI %d-%d\n",
2873		idx, mpc_ioapic_id(idx),
2874		mpc_ioapic_ver(idx), mpc_ioapic_addr(idx),
2875		gsi_cfg->gsi_base, gsi_cfg->gsi_end);
2876
2877	return 0;
2878}
2879
2880int mp_unregister_ioapic(u32 gsi_base)
2881{
2882	int ioapic, pin;
2883	int found = 0;
2884
2885	for_each_ioapic(ioapic)
2886		if (ioapics[ioapic].gsi_config.gsi_base == gsi_base) {
2887			found = 1;
2888			break;
2889		}
 
 
2890	if (!found) {
2891		pr_warn("can't find IOAPIC for GSI %d\n", gsi_base);
2892		return -ENODEV;
2893	}
2894
2895	for_each_pin(ioapic, pin) {
2896		u32 gsi = mp_pin_to_gsi(ioapic, pin);
2897		int irq = mp_map_gsi_to_irq(gsi, 0, NULL);
2898		struct mp_chip_data *data;
2899
2900		if (irq >= 0) {
2901			data = irq_get_chip_data(irq);
2902			if (data && data->count) {
2903				pr_warn("pin%d on IOAPIC%d is still in use.\n",
2904					pin, ioapic);
2905				return -EBUSY;
2906			}
2907		}
2908	}
2909
2910	/* Mark entry not present */
2911	ioapics[ioapic].nr_registers  = 0;
2912	ioapic_destroy_irqdomain(ioapic);
2913	free_ioapic_saved_registers(ioapic);
2914	if (ioapics[ioapic].iomem_res)
2915		release_resource(ioapics[ioapic].iomem_res);
2916	clear_fixmap(FIX_IO_APIC_BASE_0 + ioapic);
2917	memset(&ioapics[ioapic], 0, sizeof(ioapics[ioapic]));
2918
2919	return 0;
2920}
2921
2922int mp_ioapic_registered(u32 gsi_base)
2923{
2924	int ioapic;
2925
2926	for_each_ioapic(ioapic)
2927		if (ioapics[ioapic].gsi_config.gsi_base == gsi_base)
2928			return 1;
2929
2930	return 0;
2931}
2932
2933static void mp_irqdomain_get_attr(u32 gsi, struct mp_chip_data *data,
2934				  struct irq_alloc_info *info)
2935{
2936	if (info && info->ioapic_valid) {
2937		data->trigger = info->ioapic_trigger;
2938		data->polarity = info->ioapic_polarity;
2939	} else if (acpi_get_override_irq(gsi, &data->trigger,
2940					 &data->polarity) < 0) {
2941		/* PCI interrupts are always active low level triggered. */
2942		data->trigger = IOAPIC_LEVEL;
2943		data->polarity = IOAPIC_POL_LOW;
2944	}
2945}
2946
2947static void mp_setup_entry(struct irq_cfg *cfg, struct mp_chip_data *data,
2948			   struct IO_APIC_route_entry *entry)
 
 
 
 
 
 
 
 
 
 
 
2949{
 
 
2950	memset(entry, 0, sizeof(*entry));
2951	entry->delivery_mode = apic->irq_delivery_mode;
2952	entry->dest_mode     = apic->irq_dest_mode;
2953	entry->dest	     = cfg->dest_apicid;
2954	entry->vector	     = cfg->vector;
2955	entry->trigger	     = data->trigger;
2956	entry->polarity	     = data->polarity;
2957	/*
2958	 * Mask level triggered irqs. Edge triggered irqs are masked
2959	 * by the irq core code in case they fire.
2960	 */
2961	if (data->trigger == IOAPIC_LEVEL)
2962		entry->mask = IOAPIC_MASKED;
2963	else
2964		entry->mask = IOAPIC_UNMASKED;
2965}
2966
2967int mp_irqdomain_alloc(struct irq_domain *domain, unsigned int virq,
2968		       unsigned int nr_irqs, void *arg)
2969{
 
 
 
2970	int ret, ioapic, pin;
2971	struct irq_cfg *cfg;
2972	struct irq_data *irq_data;
2973	struct mp_chip_data *data;
2974	struct irq_alloc_info *info = arg;
2975	unsigned long flags;
2976
2977	if (!info || nr_irqs > 1)
2978		return -EINVAL;
2979	irq_data = irq_domain_get_irq_data(domain, virq);
2980	if (!irq_data)
2981		return -EINVAL;
2982
2983	ioapic = mp_irqdomain_ioapic_idx(domain);
2984	pin = info->ioapic_pin;
2985	if (irq_find_mapping(domain, (irq_hw_number_t)pin) > 0)
2986		return -EEXIST;
2987
2988	data = kzalloc(sizeof(*data), GFP_KERNEL);
2989	if (!data)
2990		return -ENOMEM;
2991
2992	info->ioapic_entry = &data->entry;
2993	ret = irq_domain_alloc_irqs_parent(domain, virq, nr_irqs, info);
2994	if (ret < 0) {
2995		kfree(data);
2996		return ret;
2997	}
2998
2999	INIT_LIST_HEAD(&data->irq_2_pin);
3000	irq_data->hwirq = info->ioapic_pin;
3001	irq_data->chip = (domain->parent == x86_vector_domain) ?
3002			  &ioapic_chip : &ioapic_ir_chip;
3003	irq_data->chip_data = data;
3004	mp_irqdomain_get_attr(mp_pin_to_gsi(ioapic, pin), data, info);
3005
3006	cfg = irqd_cfg(irq_data);
3007	add_pin_to_irq_node(data, ioapic_alloc_attr_node(info), ioapic, pin);
 
 
 
 
 
3008
3009	local_irq_save(flags);
3010	if (info->ioapic_entry)
3011		mp_setup_entry(cfg, data, info->ioapic_entry);
3012	mp_register_handler(virq, data->trigger);
3013	if (virq < nr_legacy_irqs())
3014		legacy_pic->mask(virq);
3015	local_irq_restore(flags);
3016
3017	apic_printk(APIC_VERBOSE, KERN_DEBUG
3018		    "IOAPIC[%d]: Set routing entry (%d-%d -> 0x%x -> IRQ %d Mode:%i Active:%i Dest:%d)\n",
3019		    ioapic, mpc_ioapic_id(ioapic), pin, cfg->vector,
3020		    virq, data->trigger, data->polarity, cfg->dest_apicid);
3021
3022	return 0;
 
 
 
 
3023}
3024
3025void mp_irqdomain_free(struct irq_domain *domain, unsigned int virq,
3026		       unsigned int nr_irqs)
3027{
3028	struct irq_data *irq_data;
3029	struct mp_chip_data *data;
3030
3031	BUG_ON(nr_irqs != 1);
3032	irq_data = irq_domain_get_irq_data(domain, virq);
3033	if (irq_data && irq_data->chip_data) {
3034		data = irq_data->chip_data;
3035		__remove_pin_from_irq(data, mp_irqdomain_ioapic_idx(domain),
3036				      (int)irq_data->hwirq);
3037		WARN_ON(!list_empty(&data->irq_2_pin));
3038		kfree(irq_data->chip_data);
3039	}
3040	irq_domain_free_irqs_top(domain, virq, nr_irqs);
3041}
3042
3043int mp_irqdomain_activate(struct irq_domain *domain,
3044			  struct irq_data *irq_data, bool reserve)
3045{
3046	unsigned long flags;
3047
3048	raw_spin_lock_irqsave(&ioapic_lock, flags);
3049	ioapic_configure_entry(irq_data);
3050	raw_spin_unlock_irqrestore(&ioapic_lock, flags);
3051	return 0;
3052}
3053
3054void mp_irqdomain_deactivate(struct irq_domain *domain,
3055			     struct irq_data *irq_data)
3056{
3057	/* It won't be called for IRQ with multiple IOAPIC pins associated */
3058	ioapic_mask_entry(mp_irqdomain_ioapic_idx(domain),
3059			  (int)irq_data->hwirq);
3060}
3061
3062int mp_irqdomain_ioapic_idx(struct irq_domain *domain)
3063{
3064	return (int)(long)domain->host_data;
3065}
3066
3067const struct irq_domain_ops mp_ioapic_irqdomain_ops = {
3068	.alloc		= mp_irqdomain_alloc,
3069	.free		= mp_irqdomain_free,
3070	.activate	= mp_irqdomain_activate,
3071	.deactivate	= mp_irqdomain_deactivate,
3072};