drivers/acpi/processor_core.c - linux - Git at Google

 // SPDX-License-Identifier: GPL-2.0-only
 /*
  * Copyright (C) 2005 Intel Corporation
  * Copyright (C) 2009 Hewlett-Packard Development Company, L.P.
  *
  *	Alex Chiang <achiang@hp.com>
  *	- Unified x86/ia64 implementations
  *
  * I/O APIC hotplug support
  *	Yinghai Lu <yinghai@kernel.org>
  *	Jiang Liu <jiang.liu@intel.com>
  */
 #include <linux/export.h>
 #include <linux/acpi.h>
 #include <acpi/processor.h>

 static struct acpi_table_madt *get_madt_table(void)
 {
 	static struct acpi_table_madt *madt;
 	static int read_madt;

 	if (!read_madt) {
 		if (ACPI_FAILURE(acpi_get_table(ACPI_SIG_MADT, 0,
 					(struct acpi_table_header **)&madt)))
 			madt = NULL;
 		read_madt++;
 	}

 	return madt;
 }

 static int map_lapic_id(struct acpi_subtable_header *entry,
 		 u32 acpi_id, phys_cpuid_t *apic_id)
 {
 	struct acpi_madt_local_apic *lapic =
 		container_of(entry, struct acpi_madt_local_apic, header);

 	if (!(lapic->lapic_flags & ACPI_MADT_ENABLED))
 		return -ENODEV;

 	if (lapic->processor_id != acpi_id)
 		return -EINVAL;

 	*apic_id = lapic->id;
 	return 0;
 }

 static int map_x2apic_id(struct acpi_subtable_header *entry,
 		int device_declaration, u32 acpi_id, phys_cpuid_t *apic_id)
 {
 	struct acpi_madt_local_x2apic *apic =
 		container_of(entry, struct acpi_madt_local_x2apic, header);

 	if (!(apic->lapic_flags & ACPI_MADT_ENABLED))
 		return -ENODEV;

 	if (device_declaration && (apic->uid == acpi_id)) {
 		*apic_id = apic->local_apic_id;
 		return 0;
 	}

 	return -EINVAL;
 }

 static int map_lsapic_id(struct acpi_subtable_header *entry,
 		int device_declaration, u32 acpi_id, phys_cpuid_t *apic_id)
 {
 	struct acpi_madt_local_sapic *lsapic =
 		container_of(entry, struct acpi_madt_local_sapic, header);

 	if (!(lsapic->lapic_flags & ACPI_MADT_ENABLED))
 		return -ENODEV;

 	if (device_declaration) {
 		if ((entry->length < 16) || (lsapic->uid != acpi_id))
 			return -EINVAL;
 	} else if (lsapic->processor_id != acpi_id)
 		return -EINVAL;

 	*apic_id = (lsapic->id << 8) | lsapic->eid;
 	return 0;
 }

 /*
  * Retrieve the ARM CPU physical identifier (MPIDR)
  */
 static int map_gicc_mpidr(struct acpi_subtable_header *entry,
 		int device_declaration, u32 acpi_id, phys_cpuid_t *mpidr)
 {
 	struct acpi_madt_generic_interrupt *gicc =
 	    container_of(entry, struct acpi_madt_generic_interrupt, header);

 	if (!(gicc->flags & ACPI_MADT_ENABLED))
 		return -ENODEV;

 	/* device_declaration means Device object in DSDT, in the
 	 * GIC interrupt model, logical processors are required to
 	 * have a Processor Device object in the DSDT, so we should
 	 * check device_declaration here
 	 */
 	if (device_declaration && (gicc->uid == acpi_id)) {
 		*mpidr = gicc->arm_mpidr;
 		return 0;
 	}

 	return -EINVAL;
 }

 /*
  * Retrieve the RISC-V hartid for the processor
  */
 static int map_rintc_hartid(struct acpi_subtable_header *entry,
 			    int device_declaration, u32 acpi_id,
 			    phys_cpuid_t *hartid)
 {
 	struct acpi_madt_rintc *rintc =
 	    container_of(entry, struct acpi_madt_rintc, header);

 	if (!(rintc->flags & ACPI_MADT_ENABLED))
 		return -ENODEV;

 	/* device_declaration means Device object in DSDT, in the
 	 * RISC-V, logical processors are required to
 	 * have a Processor Device object in the DSDT, so we should
 	 * check device_declaration here
 	 */
 	if (device_declaration && rintc->uid == acpi_id) {
 		*hartid = rintc->hart_id;
 		return 0;
 	}

 	return -EINVAL;
 }

 /*
  * Retrieve LoongArch CPU physical id
  */
 static int map_core_pic_id(struct acpi_subtable_header *entry,
 		int device_declaration, u32 acpi_id, phys_cpuid_t *phys_id)
 {
 	struct acpi_madt_core_pic *core_pic =
 		container_of(entry, struct acpi_madt_core_pic, header);

 	if (!(core_pic->flags & ACPI_MADT_ENABLED))
 		return -ENODEV;

 	/* device_declaration means Device object in DSDT, in LoongArch
 	 * system, logical processor acpi_id is required in _UID property
 	 * of DSDT table, so we should check device_declaration here
 	 */
 	if (device_declaration && (core_pic->processor_id == acpi_id)) {
 		*phys_id = core_pic->core_id;
 		return 0;
 	}

 	return -EINVAL;
 }

 static phys_cpuid_t map_madt_entry(struct acpi_table_madt *madt,
 				   int type, u32 acpi_id)
 {
 	unsigned long madt_end, entry;
 	phys_cpuid_t phys_id = PHYS_CPUID_INVALID;	/* CPU hardware ID */

 	if (!madt)
 		return phys_id;

 	entry = (unsigned long)madt;
 	madt_end = entry + madt->header.length;

 	/* Parse all entries looking for a match. */

 	entry += sizeof(struct acpi_table_madt);
 	while (entry + sizeof(struct acpi_subtable_header) < madt_end) {
 		struct acpi_subtable_header *header =
 			(struct acpi_subtable_header *)entry;
 		if (header->type == ACPI_MADT_TYPE_LOCAL_APIC) {
 			if (!map_lapic_id(header, acpi_id, &phys_id))
 				break;
 		} else if (header->type == ACPI_MADT_TYPE_LOCAL_X2APIC) {
 			if (!map_x2apic_id(header, type, acpi_id, &phys_id))
 				break;
 		} else if (header->type == ACPI_MADT_TYPE_LOCAL_SAPIC) {
 			if (!map_lsapic_id(header, type, acpi_id, &phys_id))
 				break;
 		} else if (header->type == ACPI_MADT_TYPE_GENERIC_INTERRUPT) {
 			if (!map_gicc_mpidr(header, type, acpi_id, &phys_id))
 				break;
 		} else if (header->type == ACPI_MADT_TYPE_RINTC) {
 			if (!map_rintc_hartid(header, type, acpi_id, &phys_id))
 				break;
 		} else if (header->type == ACPI_MADT_TYPE_CORE_PIC) {
 			if (!map_core_pic_id(header, type, acpi_id, &phys_id))
 				break;
 		}
 		entry += header->length;
 	}
 	return phys_id;
 }

 phys_cpuid_t __init acpi_map_madt_entry(u32 acpi_id)
 {
 	struct acpi_table_madt *madt = NULL;
 	phys_cpuid_t rv;

 	acpi_get_table(ACPI_SIG_MADT, 0,
 		       (struct acpi_table_header **)&madt);
 	if (!madt)
 		return PHYS_CPUID_INVALID;

 	rv = map_madt_entry(madt, 1, acpi_id);

 	acpi_put_table((struct acpi_table_header *)madt);

 	return rv;
 }

 static phys_cpuid_t map_mat_entry(acpi_handle handle, int type, u32 acpi_id)
 {
 	struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
 	union acpi_object *obj;
 	struct acpi_subtable_header *header;
 	phys_cpuid_t phys_id = PHYS_CPUID_INVALID;

 	if (ACPI_FAILURE(acpi_evaluate_object(handle, "_MAT", NULL, &buffer)))
 		goto exit;

 	if (!buffer.length || !buffer.pointer)
 		goto exit;

 	obj = buffer.pointer;
 	if (obj->type != ACPI_TYPE_BUFFER ||
 	    obj->buffer.length < sizeof(struct acpi_subtable_header)) {
 		goto exit;
 	}

 	header = (struct acpi_subtable_header *)obj->buffer.pointer;
 	if (header->type == ACPI_MADT_TYPE_LOCAL_APIC)
 		map_lapic_id(header, acpi_id, &phys_id);
 	else if (header->type == ACPI_MADT_TYPE_LOCAL_SAPIC)
 		map_lsapic_id(header, type, acpi_id, &phys_id);
 	else if (header->type == ACPI_MADT_TYPE_LOCAL_X2APIC)
 		map_x2apic_id(header, type, acpi_id, &phys_id);
 	else if (header->type == ACPI_MADT_TYPE_GENERIC_INTERRUPT)
 		map_gicc_mpidr(header, type, acpi_id, &phys_id);
 	else if (header->type == ACPI_MADT_TYPE_CORE_PIC)
 		map_core_pic_id(header, type, acpi_id, &phys_id);

 exit:
 	kfree(buffer.pointer);
 	return phys_id;
 }

 phys_cpuid_t acpi_get_phys_id(acpi_handle handle, int type, u32 acpi_id)
 {
 	phys_cpuid_t phys_id;

 	phys_id = map_mat_entry(handle, type, acpi_id);
 	if (invalid_phys_cpuid(phys_id))
 		phys_id = map_madt_entry(get_madt_table(), type, acpi_id);

 	return phys_id;
 }
 EXPORT_SYMBOL_GPL(acpi_get_phys_id);

 int acpi_map_cpuid(phys_cpuid_t phys_id, u32 acpi_id)
 {
 #ifdef CONFIG_SMP
 	int i;
 #endif

 	if (invalid_phys_cpuid(phys_id)) {
 		/*
 		 * On UP processor, there is no _MAT or MADT table.
 		 * So above phys_id is always set to PHYS_CPUID_INVALID.
 		 *
 		 * BIOS may define multiple CPU handles even for UP processor.
 		 * For example,
 		 *
 		 * Scope (_PR)
 		 * {
 		 *     Processor (CPU0, 0x00, 0x00000410, 0x06) {}
 		 *     Processor (CPU1, 0x01, 0x00000410, 0x06) {}
 		 *     Processor (CPU2, 0x02, 0x00000410, 0x06) {}
 		 *     Processor (CPU3, 0x03, 0x00000410, 0x06) {}
 		 * }
 		 *
 		 * Ignores phys_id and always returns 0 for the processor
 		 * handle with acpi id 0 if nr_cpu_ids is 1.
 		 * This should be the case if SMP tables are not found.
 		 * Return -EINVAL for other CPU's handle.
 		 */
 		if (nr_cpu_ids <= 1 && acpi_id == 0)
 			return acpi_id;
 		else
 			return -EINVAL;
 	}

 #ifdef CONFIG_SMP
 	for_each_possible_cpu(i) {
 		if (cpu_physical_id(i) == phys_id)
 			return i;
 	}
 #else
 	/* In UP kernel, only processor 0 is valid */
 	if (phys_id == 0)
 		return phys_id;
 #endif
 	return -ENODEV;
 }

 int acpi_get_cpuid(acpi_handle handle, int type, u32 acpi_id)
 {
 	phys_cpuid_t phys_id;

 	phys_id = acpi_get_phys_id(handle, type, acpi_id);

 	return acpi_map_cpuid(phys_id, acpi_id);
 }
 EXPORT_SYMBOL_GPL(acpi_get_cpuid);

 #ifdef CONFIG_ACPI_HOTPLUG_IOAPIC
 static int get_ioapic_id(struct acpi_subtable_header *entry, u32 gsi_base,
 			 u64 *phys_addr, int *ioapic_id)
 {
 	struct acpi_madt_io_apic *ioapic = (struct acpi_madt_io_apic *)entry;

 	if (ioapic->global_irq_base != gsi_base)
 		return 0;

 	*phys_addr = ioapic->address;
 	*ioapic_id = ioapic->id;
 	return 1;
 }

 static int parse_madt_ioapic_entry(u32 gsi_base, u64 *phys_addr)
 {
 	struct acpi_subtable_header *hdr;
 	unsigned long madt_end, entry;
 	struct acpi_table_madt *madt;
 	int apic_id = -1;

 	madt = get_madt_table();
 	if (!madt)
 		return apic_id;

 	entry = (unsigned long)madt;
 	madt_end = entry + madt->header.length;

 	/* Parse all entries looking for a match. */
 	entry += sizeof(struct acpi_table_madt);
 	while (entry + sizeof(struct acpi_subtable_header) < madt_end) {
 		hdr = (struct acpi_subtable_header *)entry;
 		if (hdr->type == ACPI_MADT_TYPE_IO_APIC &&
 		    get_ioapic_id(hdr, gsi_base, phys_addr, &apic_id))
 			break;
 		else
 			entry += hdr->length;
 	}

 	return apic_id;
 }

 static int parse_mat_ioapic_entry(acpi_handle handle, u32 gsi_base,
 				  u64 *phys_addr)
 {
 	struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
 	struct acpi_subtable_header *header;
 	union acpi_object *obj;
 	int apic_id = -1;

 	if (ACPI_FAILURE(acpi_evaluate_object(handle, "_MAT", NULL, &buffer)))
 		goto exit;

 	if (!buffer.length || !buffer.pointer)
 		goto exit;

 	obj = buffer.pointer;
 	if (obj->type != ACPI_TYPE_BUFFER ||
 	    obj->buffer.length < sizeof(struct acpi_subtable_header))
 		goto exit;

 	header = (struct acpi_subtable_header *)obj->buffer.pointer;
 	if (header->type == ACPI_MADT_TYPE_IO_APIC)
 		get_ioapic_id(header, gsi_base, phys_addr, &apic_id);

 exit:
 	kfree(buffer.pointer);
 	return apic_id;
 }

 /**
  * acpi_get_ioapic_id - Get IOAPIC ID and physical address matching @gsi_base
  * @handle:	ACPI object for IOAPIC device
  * @gsi_base:	GSI base to match with
  * @phys_addr:	Pointer to store physical address of matching IOAPIC record
  *
  * Walk resources returned by ACPI_MAT method, then ACPI MADT table, to search
  * for an ACPI IOAPIC record matching @gsi_base.
  * Return IOAPIC id and store physical address in @phys_addr if found a match,
  * otherwise return <0.
  */
 int acpi_get_ioapic_id(acpi_handle handle, u32 gsi_base, u64 *phys_addr)
 {
 	int apic_id;

 	apic_id = parse_mat_ioapic_entry(handle, gsi_base, phys_addr);
 	if (apic_id == -1)
 		apic_id = parse_madt_ioapic_entry(gsi_base, phys_addr);

 	return apic_id;
 }
 #endif /* CONFIG_ACPI_HOTPLUG_IOAPIC */
	// SPDX-License-Identifier: GPL-2.0-only
	/*
	* Copyright (C) 2005 Intel Corporation
	* Copyright (C) 2009 Hewlett-Packard Development Company, L.P.
	*
	* Alex Chiang <achiang@hp.com>
	* - Unified x86/ia64 implementations
	*
	* I/O APIC hotplug support
	* Yinghai Lu <yinghai@kernel.org>
	* Jiang Liu <jiang.liu@intel.com>
	*/
	#include <linux/export.h>
	#include <linux/acpi.h>
	#include <acpi/processor.h>

	static struct acpi_table_madt *get_madt_table(void)
	{
	static struct acpi_table_madt *madt;
	static int read_madt;

	if (!read_madt) {
	if (ACPI_FAILURE(acpi_get_table(ACPI_SIG_MADT, 0,
	(struct acpi_table_header **)&madt)))
	madt = NULL;
	read_madt++;
	}

	return madt;
	}

	static int map_lapic_id(struct acpi_subtable_header *entry,
	u32 acpi_id, phys_cpuid_t *apic_id)
	{
	struct acpi_madt_local_apic *lapic =
	container_of(entry, struct acpi_madt_local_apic, header);

	if (!(lapic->lapic_flags & ACPI_MADT_ENABLED))
	return -ENODEV;

	if (lapic->processor_id != acpi_id)
	return -EINVAL;

	*apic_id = lapic->id;
	return 0;
	}

	static int map_x2apic_id(struct acpi_subtable_header *entry,
	int device_declaration, u32 acpi_id, phys_cpuid_t *apic_id)
	{
	struct acpi_madt_local_x2apic *apic =
	container_of(entry, struct acpi_madt_local_x2apic, header);

	if (!(apic->lapic_flags & ACPI_MADT_ENABLED))
	return -ENODEV;

	if (device_declaration && (apic->uid == acpi_id)) {
	*apic_id = apic->local_apic_id;
	return 0;
	}

	return -EINVAL;
	}

	static int map_lsapic_id(struct acpi_subtable_header *entry,
	int device_declaration, u32 acpi_id, phys_cpuid_t *apic_id)
	{
	struct acpi_madt_local_sapic *lsapic =
	container_of(entry, struct acpi_madt_local_sapic, header);

	if (!(lsapic->lapic_flags & ACPI_MADT_ENABLED))
	return -ENODEV;

	if (device_declaration) {
	if ((entry->length < 16) \|\| (lsapic->uid != acpi_id))
	return -EINVAL;
	} else if (lsapic->processor_id != acpi_id)
	return -EINVAL;

	*apic_id = (lsapic->id << 8) \| lsapic->eid;
	return 0;
	}

	/*
	* Retrieve the ARM CPU physical identifier (MPIDR)
	*/
	static int map_gicc_mpidr(struct acpi_subtable_header *entry,
	int device_declaration, u32 acpi_id, phys_cpuid_t *mpidr)
	{
	struct acpi_madt_generic_interrupt *gicc =
	container_of(entry, struct acpi_madt_generic_interrupt, header);

	if (!(gicc->flags & ACPI_MADT_ENABLED))
	return -ENODEV;

	/* device_declaration means Device object in DSDT, in the
	* GIC interrupt model, logical processors are required to
	* have a Processor Device object in the DSDT, so we should
	* check device_declaration here
	*/
	if (device_declaration && (gicc->uid == acpi_id)) {
	*mpidr = gicc->arm_mpidr;
	return 0;
	}

	return -EINVAL;
	}

	/*
	* Retrieve the RISC-V hartid for the processor
	*/
	static int map_rintc_hartid(struct acpi_subtable_header *entry,
	int device_declaration, u32 acpi_id,
	phys_cpuid_t *hartid)
	{
	struct acpi_madt_rintc *rintc =
	container_of(entry, struct acpi_madt_rintc, header);

	if (!(rintc->flags & ACPI_MADT_ENABLED))
	return -ENODEV;

	/* device_declaration means Device object in DSDT, in the
	* RISC-V, logical processors are required to
	* have a Processor Device object in the DSDT, so we should
	* check device_declaration here
	*/
	if (device_declaration && rintc->uid == acpi_id) {
	*hartid = rintc->hart_id;
	return 0;
	}

	return -EINVAL;
	}

	/*
	* Retrieve LoongArch CPU physical id
	*/
	static int map_core_pic_id(struct acpi_subtable_header *entry,
	int device_declaration, u32 acpi_id, phys_cpuid_t *phys_id)
	{
	struct acpi_madt_core_pic *core_pic =
	container_of(entry, struct acpi_madt_core_pic, header);

	if (!(core_pic->flags & ACPI_MADT_ENABLED))
	return -ENODEV;

	/* device_declaration means Device object in DSDT, in LoongArch
	* system, logical processor acpi_id is required in _UID property
	* of DSDT table, so we should check device_declaration here
	*/
	if (device_declaration && (core_pic->processor_id == acpi_id)) {
	*phys_id = core_pic->core_id;
	return 0;
	}

	return -EINVAL;
	}

	static phys_cpuid_t map_madt_entry(struct acpi_table_madt *madt,
	int type, u32 acpi_id)
	{
	unsigned long madt_end, entry;
	phys_cpuid_t phys_id = PHYS_CPUID_INVALID; /* CPU hardware ID */

	if (!madt)
	return phys_id;

	entry = (unsigned long)madt;
	madt_end = entry + madt->header.length;

	/* Parse all entries looking for a match. */

	entry += sizeof(struct acpi_table_madt);
	while (entry + sizeof(struct acpi_subtable_header) < madt_end) {
	struct acpi_subtable_header *header =
	(struct acpi_subtable_header *)entry;
	if (header->type == ACPI_MADT_TYPE_LOCAL_APIC) {
	if (!map_lapic_id(header, acpi_id, &phys_id))
	break;
	} else if (header->type == ACPI_MADT_TYPE_LOCAL_X2APIC) {
	if (!map_x2apic_id(header, type, acpi_id, &phys_id))
	break;
	} else if (header->type == ACPI_MADT_TYPE_LOCAL_SAPIC) {
	if (!map_lsapic_id(header, type, acpi_id, &phys_id))
	break;
	} else if (header->type == ACPI_MADT_TYPE_GENERIC_INTERRUPT) {
	if (!map_gicc_mpidr(header, type, acpi_id, &phys_id))
	break;
	} else if (header->type == ACPI_MADT_TYPE_RINTC) {
	if (!map_rintc_hartid(header, type, acpi_id, &phys_id))
	break;
	} else if (header->type == ACPI_MADT_TYPE_CORE_PIC) {
	if (!map_core_pic_id(header, type, acpi_id, &phys_id))
	break;
	}
	entry += header->length;
	}
	return phys_id;
	}

	phys_cpuid_t __init acpi_map_madt_entry(u32 acpi_id)
	{
	struct acpi_table_madt *madt = NULL;
	phys_cpuid_t rv;

	acpi_get_table(ACPI_SIG_MADT, 0,
	(struct acpi_table_header **)&madt);
	if (!madt)
	return PHYS_CPUID_INVALID;

	rv = map_madt_entry(madt, 1, acpi_id);

	acpi_put_table((struct acpi_table_header *)madt);

	return rv;
	}

	static phys_cpuid_t map_mat_entry(acpi_handle handle, int type, u32 acpi_id)
	{
	struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
	union acpi_object *obj;
	struct acpi_subtable_header *header;
	phys_cpuid_t phys_id = PHYS_CPUID_INVALID;

	if (ACPI_FAILURE(acpi_evaluate_object(handle, "_MAT", NULL, &buffer)))
	goto exit;

	if (!buffer.length \|\| !buffer.pointer)
	goto exit;

	obj = buffer.pointer;
	if (obj->type != ACPI_TYPE_BUFFER \|\|
	obj->buffer.length < sizeof(struct acpi_subtable_header)) {
	goto exit;
	}

	header = (struct acpi_subtable_header *)obj->buffer.pointer;
	if (header->type == ACPI_MADT_TYPE_LOCAL_APIC)
	map_lapic_id(header, acpi_id, &phys_id);
	else if (header->type == ACPI_MADT_TYPE_LOCAL_SAPIC)
	map_lsapic_id(header, type, acpi_id, &phys_id);
	else if (header->type == ACPI_MADT_TYPE_LOCAL_X2APIC)
	map_x2apic_id(header, type, acpi_id, &phys_id);
	else if (header->type == ACPI_MADT_TYPE_GENERIC_INTERRUPT)
	map_gicc_mpidr(header, type, acpi_id, &phys_id);
	else if (header->type == ACPI_MADT_TYPE_CORE_PIC)
	map_core_pic_id(header, type, acpi_id, &phys_id);

	exit:
	kfree(buffer.pointer);
	return phys_id;
	}

	phys_cpuid_t acpi_get_phys_id(acpi_handle handle, int type, u32 acpi_id)
	{
	phys_cpuid_t phys_id;

	phys_id = map_mat_entry(handle, type, acpi_id);
	if (invalid_phys_cpuid(phys_id))
	phys_id = map_madt_entry(get_madt_table(), type, acpi_id);

	return phys_id;
	}
	EXPORT_SYMBOL_GPL(acpi_get_phys_id);

	int acpi_map_cpuid(phys_cpuid_t phys_id, u32 acpi_id)
	{
	#ifdef CONFIG_SMP
	int i;
	#endif

	if (invalid_phys_cpuid(phys_id)) {
	/*
	* On UP processor, there is no _MAT or MADT table.
	* So above phys_id is always set to PHYS_CPUID_INVALID.
	*
	* BIOS may define multiple CPU handles even for UP processor.
	* For example,
	*
	* Scope (_PR)
	* {
	* Processor (CPU0, 0x00, 0x00000410, 0x06) {}
	* Processor (CPU1, 0x01, 0x00000410, 0x06) {}
	* Processor (CPU2, 0x02, 0x00000410, 0x06) {}
	* Processor (CPU3, 0x03, 0x00000410, 0x06) {}
	* }
	*
	* Ignores phys_id and always returns 0 for the processor
	* handle with acpi id 0 if nr_cpu_ids is 1.
	* This should be the case if SMP tables are not found.
	* Return -EINVAL for other CPU's handle.
	*/
	if (nr_cpu_ids <= 1 && acpi_id == 0)
	return acpi_id;
	else
	return -EINVAL;
	}

	#ifdef CONFIG_SMP
	for_each_possible_cpu(i) {
	if (cpu_physical_id(i) == phys_id)
	return i;
	}
	#else
	/* In UP kernel, only processor 0 is valid */
	if (phys_id == 0)
	return phys_id;
	#endif
	return -ENODEV;
	}

	int acpi_get_cpuid(acpi_handle handle, int type, u32 acpi_id)
	{
	phys_cpuid_t phys_id;

	phys_id = acpi_get_phys_id(handle, type, acpi_id);

	return acpi_map_cpuid(phys_id, acpi_id);
	}
	EXPORT_SYMBOL_GPL(acpi_get_cpuid);

	#ifdef CONFIG_ACPI_HOTPLUG_IOAPIC
	static int get_ioapic_id(struct acpi_subtable_header *entry, u32 gsi_base,
	u64 phys_addr, int ioapic_id)
	{
	struct acpi_madt_io_apic ioapic = (struct acpi_madt_io_apic )entry;

	if (ioapic->global_irq_base != gsi_base)
	return 0;

	*phys_addr = ioapic->address;
	*ioapic_id = ioapic->id;
	return 1;
	}

	static int parse_madt_ioapic_entry(u32 gsi_base, u64 *phys_addr)
	{
	struct acpi_subtable_header *hdr;
	unsigned long madt_end, entry;
	struct acpi_table_madt *madt;
	int apic_id = -1;

	madt = get_madt_table();
	if (!madt)
	return apic_id;

	entry = (unsigned long)madt;
	madt_end = entry + madt->header.length;

	/* Parse all entries looking for a match. */
	entry += sizeof(struct acpi_table_madt);
	while (entry + sizeof(struct acpi_subtable_header) < madt_end) {
	hdr = (struct acpi_subtable_header *)entry;
	if (hdr->type == ACPI_MADT_TYPE_IO_APIC &&
	get_ioapic_id(hdr, gsi_base, phys_addr, &apic_id))
	break;
	else
	entry += hdr->length;
	}

	return apic_id;
	}

	static int parse_mat_ioapic_entry(acpi_handle handle, u32 gsi_base,
	u64 *phys_addr)
	{
	struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
	struct acpi_subtable_header *header;
	union acpi_object *obj;
	int apic_id = -1;

	if (ACPI_FAILURE(acpi_evaluate_object(handle, "_MAT", NULL, &buffer)))
	goto exit;

	if (!buffer.length \|\| !buffer.pointer)
	goto exit;

	obj = buffer.pointer;
	if (obj->type != ACPI_TYPE_BUFFER \|\|
	obj->buffer.length < sizeof(struct acpi_subtable_header))
	goto exit;

	header = (struct acpi_subtable_header *)obj->buffer.pointer;
	if (header->type == ACPI_MADT_TYPE_IO_APIC)
	get_ioapic_id(header, gsi_base, phys_addr, &apic_id);

	exit:
	kfree(buffer.pointer);
	return apic_id;
	}

	/**
	* acpi_get_ioapic_id - Get IOAPIC ID and physical address matching @gsi_base
	* @handle: ACPI object for IOAPIC device
	* @gsi_base: GSI base to match with
	* @phys_addr: Pointer to store physical address of matching IOAPIC record
	*
	* Walk resources returned by ACPI_MAT method, then ACPI MADT table, to search
	* for an ACPI IOAPIC record matching @gsi_base.
	* Return IOAPIC id and store physical address in @phys_addr if found a match,
	* otherwise return <0.
	*/
	int acpi_get_ioapic_id(acpi_handle handle, u32 gsi_base, u64 *phys_addr)
	{
	int apic_id;

	apic_id = parse_mat_ioapic_entry(handle, gsi_base, phys_addr);
	if (apic_id == -1)
	apic_id = parse_madt_ioapic_entry(gsi_base, phys_addr);

	return apic_id;
	}
	#endif /* CONFIG_ACPI_HOTPLUG_IOAPIC */