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authorLinus Torvalds <torvalds@linux-foundation.org>2016-10-04 01:36:06 +0300
committerLinus Torvalds <torvalds@linux-foundation.org>2016-10-04 01:36:06 +0300
commit110a9e42b68719f584879c5c5c727bbae90d15f9 (patch)
treef5f98042b98347428aa4514f6cba8eec51a21ef3 /drivers/acpi
parentaf79ad2b1f337a00aa150b993635b10bc68dc842 (diff)
parenteb6296dec19f304199ae389e6863ecc1fc74b7c7 (diff)
downloadlinux-110a9e42b68719f584879c5c5c727bbae90d15f9.tar.xz
Merge branch 'x86-apic-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 apic updates from Ingo Molnar: "The main changes are: - Persistent CPU/node numbering across CPU hotplug/unplug events. This is a pretty involved series of changes that first fetches all the information during bootup and then uses it for the various hotplug/unplug methods. (Gu Zheng, Dou Liyang) - IO-APIC hot-add/remove fixes and enhancements. (Rui Wang) - ... various fixes, cleanups and enhancements" * 'x86-apic-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (22 commits) x86/apic: Fix silent & fatal merge conflict in __generic_processor_info() acpi: Fix broken error check in map_processor() acpi: Validate processor id when mapping the processor acpi: Provide mechanism to validate processors in the ACPI tables x86/acpi: Set persistent cpuid <-> nodeid mapping when booting x86/acpi: Enable MADT APIs to return disabled apicids x86/acpi: Introduce persistent storage for cpuid <-> apicid mapping x86/acpi: Enable acpi to register all possible cpus at boot time x86/numa: Online memory-less nodes at boot time x86/apic: Get rid of apic_version[] array x86/apic: Order irq_enter/exit() calls correctly vs. ack_APIC_irq() x86/ioapic: Ignore root bridges without a companion ACPI device x86/apic: Update comment about disabling processor focus x86/smpboot: Check APIC ID before setting up default routing x86/ioapic: Fix IOAPIC failing to request resource x86/ioapic: Fix lost IOAPIC resource after hot-removal and hotadd x86/ioapic: Fix setup_res() failing to get resource x86/ioapic: Support hot-removal of IOAPICs present during boot x86/ioapic: Change prototype of acpi_ioapic_add() x86/apic, ACPI: Fix incorrect assignment when handling apic/x2apic entries ...
Diffstat (limited to 'drivers/acpi')
-rw-r--r--drivers/acpi/acpi_processor.c104
-rw-r--r--drivers/acpi/bus.c1
-rw-r--r--drivers/acpi/internal.h2
-rw-r--r--drivers/acpi/ioapic.c46
-rw-r--r--drivers/acpi/pci_root.c12
-rw-r--r--drivers/acpi/processor_core.c133
6 files changed, 252 insertions, 46 deletions
diff --git a/drivers/acpi/acpi_processor.c b/drivers/acpi/acpi_processor.c
index c7ba948d253c..3de3b6b8f0f1 100644
--- a/drivers/acpi/acpi_processor.c
+++ b/drivers/acpi/acpi_processor.c
@@ -182,6 +182,11 @@ int __weak arch_register_cpu(int cpu)
void __weak arch_unregister_cpu(int cpu) {}
+int __weak acpi_map_cpu2node(acpi_handle handle, int cpu, int physid)
+{
+ return -ENODEV;
+}
+
static int acpi_processor_hotadd_init(struct acpi_processor *pr)
{
unsigned long long sta;
@@ -300,8 +305,11 @@ static int acpi_processor_get_info(struct acpi_device *device)
* Extra Processor objects may be enumerated on MP systems with
* less than the max # of CPUs. They should be ignored _iff
* they are physically not present.
+ *
+ * NOTE: Even if the processor has a cpuid, it may not be present
+ * because cpuid <-> apicid mapping is persistent now.
*/
- if (invalid_logical_cpuid(pr->id)) {
+ if (invalid_logical_cpuid(pr->id) || !cpu_present(pr->id)) {
int ret = acpi_processor_hotadd_init(pr);
if (ret)
return ret;
@@ -573,8 +581,102 @@ static struct acpi_scan_handler processor_container_handler = {
.attach = acpi_processor_container_attach,
};
+/* The number of the unique processor IDs */
+static int nr_unique_ids __initdata;
+
+/* The number of the duplicate processor IDs */
+static int nr_duplicate_ids __initdata;
+
+/* Used to store the unique processor IDs */
+static int unique_processor_ids[] __initdata = {
+ [0 ... NR_CPUS - 1] = -1,
+};
+
+/* Used to store the duplicate processor IDs */
+static int duplicate_processor_ids[] __initdata = {
+ [0 ... NR_CPUS - 1] = -1,
+};
+
+static void __init processor_validated_ids_update(int proc_id)
+{
+ int i;
+
+ if (nr_unique_ids == NR_CPUS||nr_duplicate_ids == NR_CPUS)
+ return;
+
+ /*
+ * Firstly, compare the proc_id with duplicate IDs, if the proc_id is
+ * already in the IDs, do nothing.
+ */
+ for (i = 0; i < nr_duplicate_ids; i++) {
+ if (duplicate_processor_ids[i] == proc_id)
+ return;
+ }
+
+ /*
+ * Secondly, compare the proc_id with unique IDs, if the proc_id is in
+ * the IDs, put it in the duplicate IDs.
+ */
+ for (i = 0; i < nr_unique_ids; i++) {
+ if (unique_processor_ids[i] == proc_id) {
+ duplicate_processor_ids[nr_duplicate_ids] = proc_id;
+ nr_duplicate_ids++;
+ return;
+ }
+ }
+
+ /*
+ * Lastly, the proc_id is a unique ID, put it in the unique IDs.
+ */
+ unique_processor_ids[nr_unique_ids] = proc_id;
+ nr_unique_ids++;
+}
+
+static acpi_status __init acpi_processor_ids_walk(acpi_handle handle,
+ u32 lvl,
+ void *context,
+ void **rv)
+{
+ acpi_status status;
+ union acpi_object object = { 0 };
+ struct acpi_buffer buffer = { sizeof(union acpi_object), &object };
+
+ status = acpi_evaluate_object(handle, NULL, NULL, &buffer);
+ if (ACPI_FAILURE(status))
+ acpi_handle_info(handle, "Not get the processor object\n");
+ else
+ processor_validated_ids_update(object.processor.proc_id);
+
+ return AE_OK;
+}
+
+static void __init acpi_processor_check_duplicates(void)
+{
+ /* Search all processor nodes in ACPI namespace */
+ acpi_walk_namespace(ACPI_TYPE_PROCESSOR, ACPI_ROOT_OBJECT,
+ ACPI_UINT32_MAX,
+ acpi_processor_ids_walk,
+ NULL, NULL, NULL);
+}
+
+bool __init acpi_processor_validate_proc_id(int proc_id)
+{
+ int i;
+
+ /*
+ * compare the proc_id with duplicate IDs, if the proc_id is already
+ * in the duplicate IDs, return true, otherwise, return false.
+ */
+ for (i = 0; i < nr_duplicate_ids; i++) {
+ if (duplicate_processor_ids[i] == proc_id)
+ return true;
+ }
+ return false;
+}
+
void __init acpi_processor_init(void)
{
+ acpi_processor_check_duplicates();
acpi_scan_add_handler_with_hotplug(&processor_handler, "processor");
acpi_scan_add_handler(&processor_container_handler);
}
diff --git a/drivers/acpi/bus.c b/drivers/acpi/bus.c
index 658b4c4f169f..8df0afad35a9 100644
--- a/drivers/acpi/bus.c
+++ b/drivers/acpi/bus.c
@@ -1195,6 +1195,7 @@ static int __init acpi_init(void)
acpi_wakeup_device_init();
acpi_debugger_init();
acpi_setup_sb_notify_handler();
+ acpi_set_processor_mapping();
return 0;
}
diff --git a/drivers/acpi/internal.h b/drivers/acpi/internal.h
index 4bf8bf16d096..1b41a2739dac 100644
--- a/drivers/acpi/internal.h
+++ b/drivers/acpi/internal.h
@@ -40,10 +40,8 @@ int acpi_sysfs_init(void);
void acpi_container_init(void);
void acpi_memory_hotplug_init(void);
#ifdef CONFIG_ACPI_HOTPLUG_IOAPIC
-int acpi_ioapic_add(struct acpi_pci_root *root);
int acpi_ioapic_remove(struct acpi_pci_root *root);
#else
-static inline int acpi_ioapic_add(struct acpi_pci_root *root) { return 0; }
static inline int acpi_ioapic_remove(struct acpi_pci_root *root) { return 0; }
#endif
#ifdef CONFIG_ACPI_DOCK
diff --git a/drivers/acpi/ioapic.c b/drivers/acpi/ioapic.c
index ccdc8db16bb8..6d7ce6e12aaa 100644
--- a/drivers/acpi/ioapic.c
+++ b/drivers/acpi/ioapic.c
@@ -46,7 +46,7 @@ static acpi_status setup_res(struct acpi_resource *acpi_res, void *data)
struct resource_win win;
res->flags = 0;
- if (acpi_dev_filter_resource_type(acpi_res, IORESOURCE_MEM) == 0)
+ if (acpi_dev_filter_resource_type(acpi_res, IORESOURCE_MEM))
return AE_OK;
if (!acpi_dev_resource_memory(acpi_res, res)) {
@@ -97,7 +97,7 @@ static acpi_status handle_ioapic_add(acpi_handle handle, u32 lvl,
unsigned long long gsi_base;
struct acpi_pci_ioapic *ioapic;
struct pci_dev *dev = NULL;
- struct resource *res = NULL;
+ struct resource *res = NULL, *pci_res = NULL, *crs_res;
char *type = NULL;
if (!acpi_is_ioapic(handle, &type))
@@ -137,23 +137,30 @@ static acpi_status handle_ioapic_add(acpi_handle handle, u32 lvl,
pci_set_master(dev);
if (pci_request_region(dev, 0, type))
goto exit_disable;
- res = &dev->resource[0];
+ pci_res = &dev->resource[0];
ioapic->pdev = dev;
} else {
pci_dev_put(dev);
dev = NULL;
+ }
- res = &ioapic->res;
- acpi_walk_resources(handle, METHOD_NAME__CRS, setup_res, res);
- if (res->flags == 0) {
- acpi_handle_warn(handle, "failed to get resource\n");
- goto exit_free;
- } else if (request_resource(&iomem_resource, res)) {
- acpi_handle_warn(handle, "failed to insert resource\n");
- goto exit_free;
- }
+ crs_res = &ioapic->res;
+ acpi_walk_resources(handle, METHOD_NAME__CRS, setup_res, crs_res);
+ crs_res->name = type;
+ crs_res->flags |= IORESOURCE_BUSY;
+ if (crs_res->flags == 0) {
+ acpi_handle_warn(handle, "failed to get resource\n");
+ goto exit_release;
+ } else if (insert_resource(&iomem_resource, crs_res)) {
+ acpi_handle_warn(handle, "failed to insert resource\n");
+ goto exit_release;
}
+ /* try pci resource first, then "_CRS" resource */
+ res = pci_res;
+ if (!res || !res->flags)
+ res = crs_res;
+
if (acpi_register_ioapic(handle, res->start, (u32)gsi_base)) {
acpi_handle_warn(handle, "failed to register IOAPIC\n");
goto exit_release;
@@ -174,14 +181,13 @@ done:
exit_release:
if (dev)
pci_release_region(dev, 0);
- else
- release_resource(res);
+ if (ioapic->res.flags && ioapic->res.parent)
+ release_resource(&ioapic->res);
exit_disable:
if (dev)
pci_disable_device(dev);
exit_put:
pci_dev_put(dev);
-exit_free:
kfree(ioapic);
exit:
mutex_unlock(&ioapic_list_lock);
@@ -189,13 +195,13 @@ exit:
return AE_OK;
}
-int acpi_ioapic_add(struct acpi_pci_root *root)
+int acpi_ioapic_add(acpi_handle root_handle)
{
acpi_status status, retval = AE_OK;
- status = acpi_walk_namespace(ACPI_TYPE_DEVICE, root->device->handle,
+ status = acpi_walk_namespace(ACPI_TYPE_DEVICE, root_handle,
UINT_MAX, handle_ioapic_add, NULL,
- root->device->handle, (void **)&retval);
+ root_handle, (void **)&retval);
return ACPI_SUCCESS(status) && ACPI_SUCCESS(retval) ? 0 : -ENODEV;
}
@@ -217,9 +223,9 @@ int acpi_ioapic_remove(struct acpi_pci_root *root)
pci_release_region(ioapic->pdev, 0);
pci_disable_device(ioapic->pdev);
pci_dev_put(ioapic->pdev);
- } else if (ioapic->res.flags && ioapic->res.parent) {
- release_resource(&ioapic->res);
}
+ if (ioapic->res.flags && ioapic->res.parent)
+ release_resource(&ioapic->res);
list_del(&ioapic->list);
kfree(ioapic);
}
diff --git a/drivers/acpi/pci_root.c b/drivers/acpi/pci_root.c
index d144168d4ef9..bf601d4df8cf 100644
--- a/drivers/acpi/pci_root.c
+++ b/drivers/acpi/pci_root.c
@@ -614,7 +614,17 @@ static int acpi_pci_root_add(struct acpi_device *device,
if (hotadd) {
pcibios_resource_survey_bus(root->bus);
pci_assign_unassigned_root_bus_resources(root->bus);
- acpi_ioapic_add(root);
+ /*
+ * This is only called for the hotadd case. For the boot-time
+ * case, we need to wait until after PCI initialization in
+ * order to deal with IOAPICs mapped in on a PCI BAR.
+ *
+ * This is currently x86-specific, because acpi_ioapic_add()
+ * is an empty function without CONFIG_ACPI_HOTPLUG_IOAPIC.
+ * And CONFIG_ACPI_HOTPLUG_IOAPIC depends on CONFIG_X86_IO_APIC
+ * (see drivers/acpi/Kconfig).
+ */
+ acpi_ioapic_add(root->device->handle);
}
pci_lock_rescan_remove();
diff --git a/drivers/acpi/processor_core.c b/drivers/acpi/processor_core.c
index 9125d7d96372..5c78ee1860b0 100644
--- a/drivers/acpi/processor_core.c
+++ b/drivers/acpi/processor_core.c
@@ -32,12 +32,12 @@ static struct acpi_table_madt *get_madt_table(void)
}
static int map_lapic_id(struct acpi_subtable_header *entry,
- u32 acpi_id, phys_cpuid_t *apic_id)
+ u32 acpi_id, phys_cpuid_t *apic_id, bool ignore_disabled)
{
struct acpi_madt_local_apic *lapic =
container_of(entry, struct acpi_madt_local_apic, header);
- if (!(lapic->lapic_flags & ACPI_MADT_ENABLED))
+ if (ignore_disabled && !(lapic->lapic_flags & ACPI_MADT_ENABLED))
return -ENODEV;
if (lapic->processor_id != acpi_id)
@@ -48,12 +48,13 @@ static int map_lapic_id(struct acpi_subtable_header *entry,
}
static int map_x2apic_id(struct acpi_subtable_header *entry,
- int device_declaration, u32 acpi_id, phys_cpuid_t *apic_id)
+ int device_declaration, u32 acpi_id, phys_cpuid_t *apic_id,
+ bool ignore_disabled)
{
struct acpi_madt_local_x2apic *apic =
container_of(entry, struct acpi_madt_local_x2apic, header);
- if (!(apic->lapic_flags & ACPI_MADT_ENABLED))
+ if (ignore_disabled && !(apic->lapic_flags & ACPI_MADT_ENABLED))
return -ENODEV;
if (device_declaration && (apic->uid == acpi_id)) {
@@ -65,12 +66,13 @@ static int map_x2apic_id(struct acpi_subtable_header *entry,
}
static int map_lsapic_id(struct acpi_subtable_header *entry,
- int device_declaration, u32 acpi_id, phys_cpuid_t *apic_id)
+ int device_declaration, u32 acpi_id, phys_cpuid_t *apic_id,
+ bool ignore_disabled)
{
struct acpi_madt_local_sapic *lsapic =
container_of(entry, struct acpi_madt_local_sapic, header);
- if (!(lsapic->lapic_flags & ACPI_MADT_ENABLED))
+ if (ignore_disabled && !(lsapic->lapic_flags & ACPI_MADT_ENABLED))
return -ENODEV;
if (device_declaration) {
@@ -87,12 +89,13 @@ static int map_lsapic_id(struct acpi_subtable_header *entry,
* 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)
+ int device_declaration, u32 acpi_id, phys_cpuid_t *mpidr,
+ bool ignore_disabled)
{
struct acpi_madt_generic_interrupt *gicc =
container_of(entry, struct acpi_madt_generic_interrupt, header);
- if (!(gicc->flags & ACPI_MADT_ENABLED))
+ if (ignore_disabled && !(gicc->flags & ACPI_MADT_ENABLED))
return -ENODEV;
/* device_declaration means Device object in DSDT, in the
@@ -109,7 +112,7 @@ static int map_gicc_mpidr(struct acpi_subtable_header *entry,
}
static phys_cpuid_t map_madt_entry(struct acpi_table_madt *madt,
- int type, u32 acpi_id)
+ int type, u32 acpi_id, bool ignore_disabled)
{
unsigned long madt_end, entry;
phys_cpuid_t phys_id = PHYS_CPUID_INVALID; /* CPU hardware ID */
@@ -127,16 +130,20 @@ static phys_cpuid_t map_madt_entry(struct acpi_table_madt *madt,
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))
+ if (!map_lapic_id(header, acpi_id, &phys_id,
+ ignore_disabled))
break;
} else if (header->type == ACPI_MADT_TYPE_LOCAL_X2APIC) {
- if (!map_x2apic_id(header, type, acpi_id, &phys_id))
+ if (!map_x2apic_id(header, type, acpi_id, &phys_id,
+ ignore_disabled))
break;
} else if (header->type == ACPI_MADT_TYPE_LOCAL_SAPIC) {
- if (!map_lsapic_id(header, type, acpi_id, &phys_id))
+ if (!map_lsapic_id(header, type, acpi_id, &phys_id,
+ ignore_disabled))
break;
} else if (header->type == ACPI_MADT_TYPE_GENERIC_INTERRUPT) {
- if (!map_gicc_mpidr(header, type, acpi_id, &phys_id))
+ if (!map_gicc_mpidr(header, type, acpi_id, &phys_id,
+ ignore_disabled))
break;
}
entry += header->length;
@@ -156,14 +163,15 @@ phys_cpuid_t __init acpi_map_madt_entry(u32 acpi_id)
if (!madt)
return PHYS_CPUID_INVALID;
- rv = map_madt_entry(madt, 1, acpi_id);
+ rv = map_madt_entry(madt, 1, acpi_id, true);
early_acpi_os_unmap_memory(madt, tbl_size);
return rv;
}
-static phys_cpuid_t map_mat_entry(acpi_handle handle, int type, u32 acpi_id)
+static phys_cpuid_t map_mat_entry(acpi_handle handle, int type, u32 acpi_id,
+ bool ignore_disabled)
{
struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
union acpi_object *obj;
@@ -184,30 +192,38 @@ static phys_cpuid_t map_mat_entry(acpi_handle handle, int type, u32 acpi_id)
header = (struct acpi_subtable_header *)obj->buffer.pointer;
if (header->type == ACPI_MADT_TYPE_LOCAL_APIC)
- map_lapic_id(header, acpi_id, &phys_id);
+ map_lapic_id(header, acpi_id, &phys_id, ignore_disabled);
else if (header->type == ACPI_MADT_TYPE_LOCAL_SAPIC)
- map_lsapic_id(header, type, acpi_id, &phys_id);
+ map_lsapic_id(header, type, acpi_id, &phys_id, ignore_disabled);
else if (header->type == ACPI_MADT_TYPE_LOCAL_X2APIC)
- map_x2apic_id(header, type, acpi_id, &phys_id);
+ map_x2apic_id(header, type, acpi_id, &phys_id, ignore_disabled);
else if (header->type == ACPI_MADT_TYPE_GENERIC_INTERRUPT)
- map_gicc_mpidr(header, type, acpi_id, &phys_id);
+ map_gicc_mpidr(header, type, acpi_id, &phys_id,
+ ignore_disabled);
exit:
kfree(buffer.pointer);
return phys_id;
}
-phys_cpuid_t acpi_get_phys_id(acpi_handle handle, int type, u32 acpi_id)
+static phys_cpuid_t __acpi_get_phys_id(acpi_handle handle, int type,
+ u32 acpi_id, bool ignore_disabled)
{
phys_cpuid_t phys_id;
- phys_id = map_mat_entry(handle, type, acpi_id);
+ phys_id = map_mat_entry(handle, type, acpi_id, ignore_disabled);
if (invalid_phys_cpuid(phys_id))
- phys_id = map_madt_entry(get_madt_table(), type, acpi_id);
+ phys_id = map_madt_entry(get_madt_table(), type, acpi_id,
+ ignore_disabled);
return phys_id;
}
+phys_cpuid_t acpi_get_phys_id(acpi_handle handle, int type, u32 acpi_id)
+{
+ return __acpi_get_phys_id(handle, type, acpi_id, true);
+}
+
int acpi_map_cpuid(phys_cpuid_t phys_id, u32 acpi_id)
{
#ifdef CONFIG_SMP
@@ -264,6 +280,79 @@ int acpi_get_cpuid(acpi_handle handle, int type, u32 acpi_id)
}
EXPORT_SYMBOL_GPL(acpi_get_cpuid);
+#ifdef CONFIG_ACPI_HOTPLUG_CPU
+static bool __init
+map_processor(acpi_handle handle, phys_cpuid_t *phys_id, int *cpuid)
+{
+ int type, id;
+ u32 acpi_id;
+ acpi_status status;
+ acpi_object_type acpi_type;
+ unsigned long long tmp;
+ union acpi_object object = { 0 };
+ struct acpi_buffer buffer = { sizeof(union acpi_object), &object };
+
+ status = acpi_get_type(handle, &acpi_type);
+ if (ACPI_FAILURE(status))
+ return false;
+
+ switch (acpi_type) {
+ case ACPI_TYPE_PROCESSOR:
+ status = acpi_evaluate_object(handle, NULL, NULL, &buffer);
+ if (ACPI_FAILURE(status))
+ return false;
+ acpi_id = object.processor.proc_id;
+
+ /* validate the acpi_id */
+ if(acpi_processor_validate_proc_id(acpi_id))
+ return false;
+ break;
+ case ACPI_TYPE_DEVICE:
+ status = acpi_evaluate_integer(handle, "_UID", NULL, &tmp);
+ if (ACPI_FAILURE(status))
+ return false;
+ acpi_id = tmp;
+ break;
+ default:
+ return false;
+ }
+
+ type = (acpi_type == ACPI_TYPE_DEVICE) ? 1 : 0;
+
+ *phys_id = __acpi_get_phys_id(handle, type, acpi_id, false);
+ id = acpi_map_cpuid(*phys_id, acpi_id);
+
+ if (id < 0)
+ return false;
+ *cpuid = id;
+ return true;
+}
+
+static acpi_status __init
+set_processor_node_mapping(acpi_handle handle, u32 lvl, void *context,
+ void **rv)
+{
+ phys_cpuid_t phys_id;
+ int cpu_id;
+
+ if (!map_processor(handle, &phys_id, &cpu_id))
+ return AE_ERROR;
+
+ acpi_map_cpu2node(handle, cpu_id, phys_id);
+ return AE_OK;
+}
+
+void __init acpi_set_processor_mapping(void)
+{
+ /* Set persistent cpu <-> node mapping for all processors. */
+ acpi_walk_namespace(ACPI_TYPE_PROCESSOR, ACPI_ROOT_OBJECT,
+ ACPI_UINT32_MAX, set_processor_node_mapping,
+ NULL, NULL, NULL);
+}
+#else
+void __init acpi_set_processor_mapping(void) {}
+#endif /* CONFIG_ACPI_HOTPLUG_CPU */
+
#ifdef CONFIG_ACPI_HOTPLUG_IOAPIC
static int get_ioapic_id(struct acpi_subtable_header *entry, u32 gsi_base,
u64 *phys_addr, int *ioapic_id)