io_apic.c

		if (gsi >= NR_IRQS_LEGACY)
			irq = gsi;
		else
			irq = gsi_top + gsi;
	}

#ifdef CONFIG_X86_32
	/*
	 * PCI IRQ command line redirection. Yes, limits are hardcoded.
	 */
	if ((pin >= 16) && (pin <= 23)) {
		if (pirq_entries[pin-16] != -1) {
			if (!pirq_entries[pin-16]) {
				apic_printk(APIC_VERBOSE, KERN_DEBUG
						"disabling PIRQ%d\n", pin-16);
			} else {
				irq = pirq_entries[pin-16];
				apic_printk(APIC_VERBOSE, KERN_DEBUG
						"using PIRQ%d -> IRQ %d\n",
						pin-16, irq);
			}
		}
	}
#endif

	return irq;
}

/*
 * Find a specific PCI IRQ entry.
 * Not an __init, possibly needed by modules
 */
int IO_APIC_get_PCI_irq_vector(int bus, int slot, int pin,
				struct io_apic_irq_attr *irq_attr)
{
	int ioapic_idx, i, best_guess = -1;

	apic_printk(APIC_DEBUG,
		    "querying PCI -> IRQ mapping bus:%d, slot:%d, pin:%d.\n",
		    bus, slot, pin);
	if (test_bit(bus, mp_bus_not_pci)) {
		apic_printk(APIC_VERBOSE,
			    "PCI BIOS passed nonexistent PCI bus %d!\n", bus);
		return -1;
	}
	for (i = 0; i < mp_irq_entries; i++) {
		int lbus = mp_irqs[i].srcbus;

		for (ioapic_idx = 0; ioapic_idx < nr_ioapics; ioapic_idx++)
			if (mpc_ioapic_id(ioapic_idx) == mp_irqs[i].dstapic ||
			    mp_irqs[i].dstapic == MP_APIC_ALL)
				break;

		if (!test_bit(lbus, mp_bus_not_pci) &&
		    !mp_irqs[i].irqtype &&
		    (bus == lbus) &&
		    (slot == ((mp_irqs[i].srcbusirq >> 2) & 0x1f))) {
			int irq = pin_2_irq(i, ioapic_idx, mp_irqs[i].dstirq);

			if (!(ioapic_idx || IO_APIC_IRQ(irq)))
				continue;

			if (pin == (mp_irqs[i].srcbusirq & 3)) {
				set_io_apic_irq_attr(irq_attr, ioapic_idx,
						     mp_irqs[i].dstirq,
						     irq_trigger(i),
						     irq_polarity(i));
				return irq;
			}
			/*
			 * Use the first all-but-pin matching entry as a
			 * best-guess fuzzy result for broken mptables.
			 */
			if (best_guess < 0) {
				set_io_apic_irq_attr(irq_attr, ioapic_idx,
						     mp_irqs[i].dstirq,
						     irq_trigger(i),
						     irq_polarity(i));
				best_guess = irq;
			}
		}
	}
	return best_guess;
}
EXPORT_SYMBOL(IO_APIC_get_PCI_irq_vector);

void lock_vector_lock(void)
{
	/* Used to the online set of cpus does not change
	 * during assign_irq_vector.
	 */
	raw_spin_lock(&vector_lock);
}

void unlock_vector_lock(void)
{
	raw_spin_unlock(&vector_lock);
}

static int
__assign_irq_vector(int irq, struct irq_cfg *cfg, const struct cpumask *mask)
{
	/*
	 * NOTE! The local APIC isn't very good at handling
	 * multiple interrupts at the same interrupt level.
	 * As the interrupt level is determined by taking the
	 * vector number and shifting that right by 4, we
	 * want to spread these out a bit so that they don't
	 * all fall in the same interrupt level.
	 *
	 * Also, we've got to be careful not to trash gate
	 * 0x80, because int 0x80 is hm, kind of importantish. ;)
	 */
	static int current_vector = FIRST_EXTERNAL_VECTOR + VECTOR_OFFSET_START;
	static int current_offset = VECTOR_OFFSET_START % 8;
	unsigned int old_vector;
	int cpu, err;
	cpumask_var_t tmp_mask;

	if (cfg->move_in_progress)
		return -EBUSY;

	if (!alloc_cpumask_var(&tmp_mask, GFP_ATOMIC))
		return -ENOMEM;

	old_vector = cfg->vector;
	if (old_vector) {
		cpumask_and(tmp_mask, mask, cpu_online_mask);
		if (cpumask_subset(tmp_mask, cfg->domain)) {
			free_cpumask_var(tmp_mask);
			return 0;
		}
	}

	/* Only try and allocate irqs on cpus that are present */
	err = -ENOSPC;
	for_each_cpu_and(cpu, mask, cpu_online_mask) {
		int new_cpu;
		int vector, offset;

		apic->vector_allocation_domain(cpu, tmp_mask);

		if (cpumask_subset(tmp_mask, cfg->domain)) {
			free_cpumask_var(tmp_mask);
			return 0;
		}

		vector = current_vector;
		offset = current_offset;
next:
		vector += 8;
		if (vector >= first_system_vector) {
			/* If out of vectors on large boxen, must share them. */
			offset = (offset + 1) % 8;
			vector = FIRST_EXTERNAL_VECTOR + offset;
		}
		if (unlikely(current_vector == vector))
			continue;

		if (test_bit(vector, used_vectors))
			goto next;

		for_each_cpu_and(new_cpu, tmp_mask, cpu_online_mask)
			if (per_cpu(vector_irq, new_cpu)[vector] != -1)
				goto next;
		/* Found one! */
		current_vector = vector;
		current_offset = offset;
		if (old_vector) {
			cfg->move_in_progress = 1;
			cpumask_copy(cfg->old_domain, cfg->domain);
		}
		for_each_cpu_and(new_cpu, tmp_mask, cpu_online_mask)
			per_cpu(vector_irq, new_cpu)[vector] = irq;
		cfg->vector = vector;
		cpumask_copy(cfg->domain, tmp_mask);
		err = 0;
		break;
	}
	free_cpumask_var(tmp_mask);
	return err;
}

int assign_irq_vector(int irq, struct irq_cfg *cfg, const struct cpumask *mask)
{
	int err;
	unsigned long flags;

	raw_spin_lock_irqsave(&vector_lock, flags);
	err = __assign_irq_vector(irq, cfg, mask);
	raw_spin_unlock_irqrestore(&vector_lock, flags);
	return err;
}

static void __clear_irq_vector(int irq, struct irq_cfg *cfg)
{
	int cpu, vector;

	BUG_ON(!cfg->vector);

	vector = cfg->vector;
	for_each_cpu_and(cpu, cfg->domain, cpu_online_mask)
		per_cpu(vector_irq, cpu)[vector] = -1;

	cfg->vector = 0;
	cpumask_clear(cfg->domain);

	if (likely(!cfg->move_in_progress))
		return;
	for_each_cpu_and(cpu, cfg->old_domain, cpu_online_mask) {
		for (vector = FIRST_EXTERNAL_VECTOR; vector < NR_VECTORS;
								vector++) {
			if (per_cpu(vector_irq, cpu)[vector] != irq)
				continue;
			per_cpu(vector_irq, cpu)[vector] = -1;
			break;
		}
	}
	cfg->move_in_progress = 0;
}

void __setup_vector_irq(int cpu)
{
	/* Initialize vector_irq on a new cpu */
	int irq, vector;
	struct irq_cfg *cfg;

	/*
	 * vector_lock will make sure that we don't run into irq vector
	 * assignments that might be happening on another cpu in parallel,
	 * while we setup our initial vector to irq mappings.
	 */
	raw_spin_lock(&vector_lock);
	/* Mark the inuse vectors */
	for_each_active_irq(irq) {
		cfg = irq_get_chip_data(irq);
		if (!cfg)
			continue;
		/*
		 * If it is a legacy IRQ handled by the legacy PIC, this cpu
		 * will be part of the irq_cfg's domain.
		 */
		if (irq < legacy_pic->nr_legacy_irqs && !IO_APIC_IRQ(irq))
			cpumask_set_cpu(cpu, cfg->domain);

		if (!cpumask_test_cpu(cpu, cfg->domain))
			continue;
		vector = cfg->vector;
		per_cpu(vector_irq, cpu)[vector] = irq;
	}
	/* Mark the free vectors */
	for (vector = 0; vector < NR_VECTORS; ++vector) {
		irq = per_cpu(vector_irq, cpu)[vector];
		if (irq < 0)
			continue;

		cfg = irq_cfg(irq);
		if (!cpumask_test_cpu(cpu, cfg->domain))
			per_cpu(vector_irq, cpu)[vector] = -1;
	}
	raw_spin_unlock(&vector_lock);
}

static struct irq_chip ioapic_chip;

#ifdef CONFIG_X86_32
static inline int IO_APIC_irq_trigger(int irq)
{
	int apic, idx, pin;

	for (apic = 0; apic < nr_ioapics; apic++) {
		for (pin = 0; pin < ioapics[apic].nr_registers; pin++) {
			idx = find_irq_entry(apic, pin, mp_INT);
			if ((idx != -1) && (irq == pin_2_irq(idx, apic, pin)))
				return irq_trigger(idx);
		}
	}
	/*
         * nonexistent IRQs are edge default
         */
	return 0;
}
#else
static inline int IO_APIC_irq_trigger(int irq)
{
	return 1;
}
#endif

static void ioapic_register_intr(unsigned int irq, struct irq_cfg *cfg,
				 unsigned long trigger)
{
	struct irq_chip *chip = &ioapic_chip;
	irq_flow_handler_t hdl;
	bool fasteoi;

	if ((trigger == IOAPIC_AUTO && IO_APIC_irq_trigger(irq)) ||
	    trigger == IOAPIC_LEVEL) {
		irq_set_status_flags(irq, IRQ_LEVEL);
		fasteoi = true;
	} else {
		irq_clear_status_flags(irq, IRQ_LEVEL);
		fasteoi = false;
	}

	if (irq_remapped(cfg)) {
		irq_set_status_flags(irq, IRQ_MOVE_PCNTXT);
		irq_remap_modify_chip_defaults(chip);
		fasteoi = trigger != 0;
	}

	hdl = fasteoi ? handle_fasteoi_irq : handle_edge_irq;
	irq_set_chip_and_handler_name(irq, chip, hdl,
				      fasteoi ? "fasteoi" : "edge");
}

static int setup_ioapic_entry(int irq, struct IO_APIC_route_entry *entry,
			       unsigned int destination, int vector,
			       struct io_apic_irq_attr *attr)
{
	if (irq_remapping_enabled)
		return setup_ioapic_remapped_entry(irq, entry, destination,
						   vector, attr);

	memset(entry, 0, sizeof(*entry));

	entry->delivery_mode = apic->irq_delivery_mode;
	entry->dest_mode     = apic->irq_dest_mode;
	entry->dest	     = destination;
	entry->vector	     = vector;
	entry->mask	     = 0;			/* enable IRQ */
	entry->trigger	     = attr->trigger;
	entry->polarity	     = attr->polarity;

	/*
	 * Mask level triggered irqs.
	 * Use IRQ_DELAYED_DISABLE for edge triggered irqs.
	 */
	if (attr->trigger)
		entry->mask = 1;

	return 0;
}

static void setup_ioapic_irq(unsigned int irq, struct irq_cfg *cfg,
				struct io_apic_irq_attr *attr)
{
	struct IO_APIC_route_entry entry;
	unsigned int dest;

	if (!IO_APIC_IRQ(irq))
		return;

	if (assign_irq_vector(irq, cfg, apic->target_cpus()))
		return;

	dest = apic->cpu_mask_to_apicid_and(cfg->domain, apic->target_cpus());

	apic_printk(APIC_VERBOSE,KERN_DEBUG
		    "IOAPIC[%d]: Set routing entry (%d-%d -> 0x%x -> "
		    "IRQ %d Mode:%i Active:%i Dest:%d)\n",
		    attr->ioapic, mpc_ioapic_id(attr->ioapic), attr->ioapic_pin,
		    cfg->vector, irq, attr->trigger, attr->polarity, dest);

	if (setup_ioapic_entry(irq, &entry, dest, cfg->vector, attr)) {
		pr_warn("Failed to setup ioapic entry for ioapic  %d, pin %d\n",
			mpc_ioapic_id(attr->ioapic), attr->ioapic_pin);
		__clear_irq_vector(irq, cfg);

		return;
	}

	ioapic_register_intr(irq, cfg, attr->trigger);
	if (irq < legacy_pic->nr_legacy_irqs)
		legacy_pic->mask(irq);

	ioapic_write_entry(attr->ioapic, attr->ioapic_pin, entry);
}

static bool __init io_apic_pin_not_connected(int idx, int ioapic_idx, int pin)
{
	if (idx != -1)
		return false;

	apic_printk(APIC_VERBOSE, KERN_DEBUG " apic %d pin %d not connected\n",
		    mpc_ioapic_id(ioapic_idx), pin);
	return true;
}

static void __init __io_apic_setup_irqs(unsigned int ioapic_idx)
{
	int idx, node = cpu_to_node(0);
	struct io_apic_irq_attr attr;
	unsigned int pin, irq;

	for (pin = 0; pin < ioapics[ioapic_idx].nr_registers; pin++) {
		idx = find_irq_entry(ioapic_idx, pin, mp_INT);
		if (io_apic_pin_not_connected(idx, ioapic_idx, pin))
			continue;

		irq = pin_2_irq(idx, ioapic_idx, pin);

		if ((ioapic_idx > 0) && (irq > 16))
			continue;

		/*
		 * Skip the timer IRQ if there's a quirk handler
		 * installed and if it returns 1:
		 */
		if (apic->multi_timer_check &&
		    apic->multi_timer_check(ioapic_idx, irq))
			continue;

		set_io_apic_irq_attr(&attr, ioapic_idx, pin, irq_trigger(idx),
				     irq_polarity(idx));

		io_apic_setup_irq_pin(irq, node, &attr);
	}
}

static void __init setup_IO_APIC_irqs(void)
{
	unsigned int ioapic_idx;

	apic_printk(APIC_VERBOSE, KERN_DEBUG "init IO_APIC IRQs\n");

	for (ioapic_idx = 0; ioapic_idx < nr_ioapics; ioapic_idx++)
		__io_apic_setup_irqs(ioapic_idx);
}

/*
 * for the gsit that is not in first ioapic
 * but could not use acpi_register_gsi()
 * like some special sci in IBM x3330
 */
void setup_IO_APIC_irq_extra(u32 gsi)
{
	int ioapic_idx = 0, pin, idx, irq, node = cpu_to_node(0);
	struct io_apic_irq_attr attr;

	/*
	 * Convert 'gsi' to 'ioapic.pin'.
	 */
	ioapic_idx = mp_find_ioapic(gsi);
	if (ioapic_idx < 0)
		return;

	pin = mp_find_ioapic_pin(ioapic_idx, gsi);
	idx = find_irq_entry(ioapic_idx, pin, mp_INT);
	if (idx == -1)
		return;

	irq = pin_2_irq(idx, ioapic_idx, pin);

	/* Only handle the non legacy irqs on secondary ioapics */
	if (ioapic_idx == 0 || irq < NR_IRQS_LEGACY)
		return;

	set_io_apic_irq_attr(&attr, ioapic_idx, pin, irq_trigger(idx),
			     irq_polarity(idx));

	io_apic_setup_irq_pin_once(irq, node, &attr);
}

/*
 * Set up the timer pin, possibly with the 8259A-master behind.
 */
static void __init setup_timer_IRQ0_pin(unsigned int ioapic_idx,
					 unsigned int pin, int vector)
{
	struct IO_APIC_route_entry entry;

	if (irq_remapping_enabled)
		return;

	memset(&entry, 0, sizeof(entry));

	/*
	 * We use logical delivery to get the timer IRQ
	 * to the first CPU.
	 */
	entry.dest_mode = apic->irq_dest_mode;
	entry.mask = 0;			/* don't mask IRQ for edge */
	entry.dest = apic->cpu_mask_to_apicid(apic->target_cpus());
	entry.delivery_mode = apic->irq_delivery_mode;
	entry.polarity = 0;
	entry.trigger = 0;
	entry.vector = vector;

	/*
	 * The timer IRQ doesn't have to know that behind the
	 * scene we may have a 8259A-master in AEOI mode ...
	 */
	irq_set_chip_and_handler_name(0, &ioapic_chip, handle_edge_irq,
				      "edge");

	/*
	 * Add it to the IO-APIC irq-routing table:
	 */
	ioapic_write_entry(ioapic_idx, pin, entry);
}

__apicdebuginit(void) print_IO_APIC(int ioapic_idx)
{
	int i;
	union IO_APIC_reg_00 reg_00;
	union IO_APIC_reg_01 reg_01;
	union IO_APIC_reg_02 reg_02;
	union IO_APIC_reg_03 reg_03;
	unsigned long flags;

	raw_spin_lock_irqsave(&ioapic_lock, flags);
	reg_00.raw = io_apic_read(ioapic_idx, 0);
	reg_01.raw = io_apic_read(ioapic_idx, 1);
	if (reg_01.bits.version >= 0x10)
		reg_02.raw = io_apic_read(ioapic_idx, 2);
	if (reg_01.bits.version >= 0x20)
		reg_03.raw = io_apic_read(ioapic_idx, 3);
	raw_spin_unlock_irqrestore(&ioapic_lock, flags);

	printk("\n");
	printk(KERN_DEBUG "IO APIC #%d......\n", mpc_ioapic_id(ioapic_idx));
	printk(KERN_DEBUG ".... register #00: %08X\n", reg_00.raw);
	printk(KERN_DEBUG ".......    : physical APIC id: %02X\n", reg_00.bits.ID);
	printk(KERN_DEBUG ".......    : Delivery Type: %X\n", reg_00.bits.delivery_type);
	printk(KERN_DEBUG ".......    : LTS          : %X\n", reg_00.bits.LTS);

	printk(KERN_DEBUG ".... register #01: %08X\n", *(int *)&reg_01);
	printk(KERN_DEBUG ".......     : max redirection entries: %02X\n",
		reg_01.bits.entries);

	printk(KERN_DEBUG ".......     : PRQ implemented: %X\n", reg_01.bits.PRQ);
	printk(KERN_DEBUG ".......     : IO APIC version: %02X\n",
		reg_01.bits.version);

	/*
	 * Some Intel chipsets with IO APIC VERSION of 0x1? don't have reg_02,
	 * but the value of reg_02 is read as the previous read register
	 * value, so ignore it if reg_02 == reg_01.
	 */
	if (reg_01.bits.version >= 0x10 && reg_02.raw != reg_01.raw) {
		printk(KERN_DEBUG ".... register #02: %08X\n", reg_02.raw);
		printk(KERN_DEBUG ".......     : arbitration: %02X\n", reg_02.bits.arbitration);
	}

	/*
	 * Some Intel chipsets with IO APIC VERSION of 0x2? don't have reg_02
	 * or reg_03, but the value of reg_0[23] is read as the previous read
	 * register value, so ignore it if reg_03 == reg_0[12].
	 */
	if (reg_01.bits.version >= 0x20 && reg_03.raw != reg_02.raw &&
	    reg_03.raw != reg_01.raw) {
		printk(KERN_DEBUG ".... register #03: %08X\n", reg_03.raw);
		printk(KERN_DEBUG ".......     : Boot DT    : %X\n", reg_03.bits.boot_DT);
	}

	printk(KERN_DEBUG ".... IRQ redirection table:\n");

	if (irq_remapping_enabled) {
		printk(KERN_DEBUG " NR Indx Fmt Mask Trig IRR"
			" Pol Stat Indx2 Zero Vect:\n");
	} else {
		printk(KERN_DEBUG " NR Dst Mask Trig IRR Pol"
			" Stat Dmod Deli Vect:\n");
	}

	for (i = 0; i <= reg_01.bits.entries; i++) {
		if (irq_remapping_enabled) {
			struct IO_APIC_route_entry entry;
			struct IR_IO_APIC_route_entry *ir_entry;

			entry = ioapic_read_entry(ioapic_idx, i);
			ir_entry = (struct IR_IO_APIC_route_entry *) &entry;
			printk(KERN_DEBUG " %02x %04X ",
				i,
				ir_entry->index
			);
			printk("%1d   %1d    %1d    %1d   %1d   "
				"%1d    %1d     %X    %02X\n",
				ir_entry->format,
				ir_entry->mask,
				ir_entry->trigger,
				ir_entry->irr,
				ir_entry->polarity,
				ir_entry->delivery_status,
				ir_entry->index2,
				ir_entry->zero,
				ir_entry->vector
			);
		} else {
			struct IO_APIC_route_entry entry;

			entry = ioapic_read_entry(ioapic_idx, i);
			printk(KERN_DEBUG " %02x %02X  ",
				i,
				entry.dest
			);
			printk("%1d    %1d    %1d   %1d   %1d    "
				"%1d    %1d    %02X\n",
				entry.mask,
				entry.trigger,
				entry.irr,
				entry.polarity,
				entry.delivery_status,
				entry.dest_mode,
				entry.delivery_mode,
				entry.vector
			);
		}
	}
}

__apicdebuginit(void) print_IO_APICs(void)
{
	int ioapic_idx;
	struct irq_cfg *cfg;
	unsigned int irq;
	struct irq_chip *chip;

	printk(KERN_DEBUG "number of MP IRQ sources: %d.\n", mp_irq_entries);
	for (ioapic_idx = 0; ioapic_idx < nr_ioapics; ioapic_idx++)
		printk(KERN_DEBUG "number of IO-APIC #%d registers: %d.\n",
		       mpc_ioapic_id(ioapic_idx),
		       ioapics[ioapic_idx].nr_registers);

	/*
	 * We are a bit conservative about what we expect.  We have to
	 * know about every hardware change ASAP.
	 */
	printk(KERN_INFO "testing the IO APIC.......................\n");

	for (ioapic_idx = 0; ioapic_idx < nr_ioapics; ioapic_idx++)
		print_IO_APIC(ioapic_idx);

	printk(KERN_DEBUG "IRQ to pin mappings:\n");
	for_each_active_irq(irq) {
		struct irq_pin_list *entry;

		chip = irq_get_chip(irq);
		if (chip != &ioapic_chip)
			continue;

		cfg = irq_get_chip_data(irq);
		if (!cfg)
			continue;
		entry = cfg->irq_2_pin;
		if (!entry)
			continue;
		printk(KERN_DEBUG "IRQ%d ", irq);
		for_each_irq_pin(entry, cfg->irq_2_pin)
			printk("-> %d:%d", entry->apic, entry->pin);
		printk("\n");
	}

	printk(KERN_INFO ".................................... done.\n");
}

__apicdebuginit(void) print_APIC_field(int base)
{
	int i;

	printk(KERN_DEBUG);

	for (i = 0; i < 8; i++)
		printk(KERN_CONT "%08x", apic_read(base + i*0x10));

	printk(KERN_CONT "\n");
}

__apicdebuginit(void) print_local_APIC(void *dummy)
{
	unsigned int i, v, ver, maxlvt;
	u64 icr;

	printk(KERN_DEBUG "printing local APIC contents on CPU#%d/%d:\n",
		smp_processor_id(), hard_smp_processor_id());
	v = apic_read(APIC_ID);
	printk(KERN_INFO "... APIC ID:      %08x (%01x)\n", v, read_apic_id());
	v = apic_read(APIC_LVR);
	printk(KERN_INFO "... APIC VERSION: %08x\n", v);
	ver = GET_APIC_VERSION(v);
	maxlvt = lapic_get_maxlvt();

	v = apic_read(APIC_TASKPRI);
	printk(KERN_DEBUG "... APIC TASKPRI: %08x (%02x)\n", v, v & APIC_TPRI_MASK);

	if (APIC_INTEGRATED(ver)) {                     /* !82489DX */
		if (!APIC_XAPIC(ver)) {
			v = apic_read(APIC_ARBPRI);
			printk(KERN_DEBUG "... APIC ARBPRI: %08x (%02x)\n", v,
			       v & APIC_ARBPRI_MASK);
		}
		v = apic_read(APIC_PROCPRI);
		printk(KERN_DEBUG "... APIC PROCPRI: %08x\n", v);
	}

	/*
	 * Remote read supported only in the 82489DX and local APIC for
	 * Pentium processors.
	 */
	if (!APIC_INTEGRATED(ver) || maxlvt == 3) {
		v = apic_read(APIC_RRR);
		printk(KERN_DEBUG "... APIC RRR: %08x\n", v);
	}

	v = apic_read(APIC_LDR);
	printk(KERN_DEBUG "... APIC LDR: %08x\n", v);
	if (!x2apic_enabled()) {
		v = apic_read(APIC_DFR);
		printk(KERN_DEBUG "... APIC DFR: %08x\n", v);
	}
	v = apic_read(APIC_SPIV);
	printk(KERN_DEBUG "... APIC SPIV: %08x\n", v);

	printk(KERN_DEBUG "... APIC ISR field:\n");
	print_APIC_field(APIC_ISR);
	printk(KERN_DEBUG "... APIC TMR field:\n");
	print_APIC_field(APIC_TMR);
	printk(KERN_DEBUG "... APIC IRR field:\n");
	print_APIC_field(APIC_IRR);

	if (APIC_INTEGRATED(ver)) {             /* !82489DX */
		if (maxlvt > 3)         /* Due to the Pentium erratum 3AP. */
			apic_write(APIC_ESR, 0);

		v = apic_read(APIC_ESR);
		printk(KERN_DEBUG "... APIC ESR: %08x\n", v);
	}

	icr = apic_icr_read();
	printk(KERN_DEBUG "... APIC ICR: %08x\n", (u32)icr);
	printk(KERN_DEBUG "... APIC ICR2: %08x\n", (u32)(icr >> 32));

	v = apic_read(APIC_LVTT);
	printk(KERN_DEBUG "... APIC LVTT: %08x\n", v);

	if (maxlvt > 3) {                       /* PC is LVT#4. */
		v = apic_read(APIC_LVTPC);
		printk(KERN_DEBUG "... APIC LVTPC: %08x\n", v);
	}
	v = apic_read(APIC_LVT0);
	printk(KERN_DEBUG "... APIC LVT0: %08x\n", v);
	v = apic_read(APIC_LVT1);
	printk(KERN_DEBUG "... APIC LVT1: %08x\n", v);

	if (maxlvt > 2) {			/* ERR is LVT#3. */
		v = apic_read(APIC_LVTERR);
		printk(KERN_DEBUG "... APIC LVTERR: %08x\n", v);
	}

	v = apic_read(APIC_TMICT);
	printk(KERN_DEBUG "... APIC TMICT: %08x\n", v);
	v = apic_read(APIC_TMCCT);
	printk(KERN_DEBUG "... APIC TMCCT: %08x\n", v);
	v = apic_read(APIC_TDCR);
	printk(KERN_DEBUG "... APIC TDCR: %08x\n", v);

	if (boot_cpu_has(X86_FEATURE_EXTAPIC)) {
		v = apic_read(APIC_EFEAT);
		maxlvt = (v >> 16) & 0xff;
		printk(KERN_DEBUG "... APIC EFEAT: %08x\n", v);
		v = apic_read(APIC_ECTRL);
		printk(KERN_DEBUG "... APIC ECTRL: %08x\n", v);
		for (i = 0; i < maxlvt; i++) {
			v = apic_read(APIC_EILVTn(i));
			printk(KERN_DEBUG "... APIC EILVT%d: %08x\n", i, v);
		}
	}
	printk("\n");
}

__apicdebuginit(void) print_local_APICs(int maxcpu)
{
	int cpu;

	if (!maxcpu)
		return;

	preempt_disable();
	for_each_online_cpu(cpu) {
		if (cpu >= maxcpu)
			break;
		smp_call_function_single(cpu, print_local_APIC, NULL, 1);
	}
	preempt_enable();
}

__apicdebuginit(void) print_PIC(void)
{
	unsigned int v;
	unsigned long flags;

	if (!legacy_pic->nr_legacy_irqs)
		return;

	printk(KERN_DEBUG "\nprinting PIC contents\n");

	raw_spin_lock_irqsave(&i8259A_lock, flags);

	v = inb(0xa1) << 8 | inb(0x21);
	printk(KERN_DEBUG "... PIC  IMR: %04x\n", v);

	v = inb(0xa0) << 8 | inb(0x20);
	printk(KERN_DEBUG "... PIC  IRR: %04x\n", v);

	outb(0x0b,0xa0);
	outb(0x0b,0x20);
	v = inb(0xa0) << 8 | inb(0x20);
	outb(0x0a,0xa0);
	outb(0x0a,0x20);

	raw_spin_unlock_irqrestore(&i8259A_lock, flags);

	printk(KERN_DEBUG "... PIC  ISR: %04x\n", v);

	v = inb(0x4d1) << 8 | inb(0x4d0);
	printk(KERN_DEBUG "... PIC ELCR: %04x\n", v);
}

static int __initdata show_lapic = 1;
static __init int setup_show_lapic(char *arg)
{
	int num = -1;

	if (strcmp(arg, "all") == 0) {
		show_lapic = CONFIG_NR_CPUS;
	} else {
		get_option(&arg, &num);
		if (num >= 0)
			show_lapic = num;
	}

	return 1;
}
__setup("show_lapic=", setup_show_lapic);

__apicdebuginit(int) print_ICs(void)
{
	if (apic_verbosity == APIC_QUIET)
		return 0;

	print_PIC();

	/* don't print out if apic is not there */
	if (!cpu_has_apic && !apic_from_smp_config())
		return 0;

	print_local_APICs(show_lapic);
	print_IO_APICs();

	return 0;
}

late_initcall(print_ICs);


/* Where if anywhere is the i8259 connect in external int mode */
static struct { int pin, apic; } ioapic_i8259 = { -1, -1 };

void __init enable_IO_APIC(void)
{
	int i8259_apic, i8259_pin;
	int apic;

	if (!legacy_pic->nr_legacy_irqs)
		return;

	for(apic = 0; apic < nr_ioapics; apic++) {
		int pin;
		/* See if any of the pins is in ExtINT mode */
		for (pin = 0; pin < ioapics[apic].nr_registers; pin++) {
			struct IO_APIC_route_entry entry;
			entry = ioapic_read_entry(apic, pin);

			/* If the interrupt line is enabled and in ExtInt mode
			 * I have found the pin where the i8259 is connected.
			 */
			if ((entry.mask == 0) && (entry.delivery_mode == dest_ExtINT)) {
				ioapic_i8259.apic = apic;
				ioapic_i8259.pin  = pin;
				goto found_i8259;
			}
		}
	}
 found_i8259:
	/* Look to see what if the MP table has reported the ExtINT */
	/* If we could not find the appropriate pin by looking at the ioapic
	 * the i8259 probably is not connected the ioapic but give the
	 * mptable a chance anyway.
	 */
	i8259_pin  = find_isa_irq_pin(0, mp_ExtINT);
	i8259_apic = find_isa_irq_apic(0, mp_ExtINT);
	/* Trust the MP table if nothing is setup in the hardware */
	if ((ioapic_i8259.pin == -1) && (i8259_pin >= 0)) {
		printk(KERN_WARNING "ExtINT not setup in hardware but reported by MP table\n");
		ioapic_i8259.pin  = i8259_pin;
		ioapic_i8259.apic = i8259_apic;
	}
	/* Complain if the MP table and the hardware disagree */
	if (((ioapic_i8259.apic != i8259_apic) || (ioapic_i8259.pin != i8259_pin)) &&
		(i8259_pin >= 0) && (ioapic_i8259.pin >= 0))
	{
		printk(KERN_WARNING "ExtINT in hardware and MP table differ\n");
	}

	/*
	 * Do not trust the IO-APIC being empty at bootup
	 */
	clear_IO_APIC();
}

/*
 * Not an __init, needed by the reboot code
 */
void disable_IO_APIC(void)
{
	/*
	 * Clear the IO-APIC before rebooting:
	 */
	clear_IO_APIC();

	if (!legacy_pic->nr_legacy_irqs)
		return;

	/*
	 * If the i8259 is routed through an IOAPIC
	 * Put that IOAPIC in virtual wire mode
	 * so legacy interrupts can be delivered.
	 *
	 * With interrupt-remapping, for now we will use virtual wire A mode,
	 * as virtual wire B is little complex (need to configure both
	 * IOAPIC RTE as well as interrupt-remapping table entry).
	 * As this gets called during crash dump, keep this simple for now.
	 */
	if (ioapic_i8259.pin != -1 && !irq_remapping_enabled) {
		struct IO_APIC_route_entry entry;

		memset(&entry, 0, sizeof(entry));
		entry.mask            = 0; /* Enabled */
		entry.trigger         = 0; /* Edge */
		entry.irr             = 0;
		entry.polarity        = 0; /* High */
		entry.delivery_status = 0;
		entry.dest_mode       = 0; /* Physical */
		entry.delivery_mode   = dest_ExtINT; /* ExtInt */
		entry.vector          = 0;
		entry.dest            = read_apic_id();

		/*
		 * Add it to the IO-APIC irq-routing table:
		 */
		ioapic_write_entry(ioapic_i8259.apic, ioapic_i8259.pin, entry);
	}

	/*
	 * Use virtual wire A mode when interrupt remapping is enabled.
	 */
	if (cpu_has_apic || apic_from_smp_config())
		disconnect_bsp_APIC(!irq_remapping_enabled &&
				ioapic_i8259.pin != -1);
}

#ifdef CONFIG_X86_32
/*
 * function to set the IO-APIC physical IDs based on the
 * values stored in the MPC table.
 *
 * by Matt Domsch <Matt_Domsch@dell.com>  Tue Dec 21 12:25:05 CST 1999
 */
void __init setup_ioapic_ids_from_mpc_nocheck(void)
{
	union IO_APIC_reg_00 reg_00;
	physid_mask_t phys_id_present_map;
	int ioapic_idx;
	int i;
	unsigned char old_id;
	unsigned long flags;

	/*
	 * This is broken; anything with a real cpu count has to
	 * circumvent this idiocy regardless.
	 */
	apic->ioapic_phys_id_map(&phys_cpu_present_map, &phys_id_present_map);

	/*
	 * Set the IOAPIC ID to the value stored in the MPC table.
	 */
	for (ioapic_idx = 0; ioapic_idx < nr_ioapics; ioapic_idx++) {
		/* Read the register 0 value */
		raw_spin_lock_irqsave(&ioapic_lock, flags);
		reg_00.raw = io_apic_read(ioapic_idx, 0);
		raw_spin_unlock_irqrestore(&ioapic_lock, flags);

		old_id = mpc_ioapic_id(ioapic_idx);

		if (mpc_ioapic_id(ioapic_idx) >= get_physical_broadcast()) {
			printk(KERN_ERR "BIOS bug, IO-APIC#%d ID is %d in the MPC table!...\n",
				ioapic_idx, mpc_ioapic_id(ioapic_idx));
			printk(KERN_ERR "... fixing up to %d. (tell your hw vendor)\n",
				reg_00.bits.ID);