2 * Copyright (C) 2005 Intel Corporation
3 * Copyright (C) 2009 Hewlett-Packard Development Company, L.P.
5 * Alex Chiang <achiang@hp.com>
6 * - Unified x86/ia64 implementations
7 * Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
8 * - Added _PDC for platforms with Intel CPUs
10 #include <linux/export.h>
11 #include <linux/dmi.h>
12 #include <linux/slab.h>
14 #include <acpi/acpi_drivers.h>
15 #include <acpi/processor.h>
19 #define PREFIX "ACPI: "
20 #define _COMPONENT ACPI_PROCESSOR_COMPONENT
21 ACPI_MODULE_NAME("processor_core");
23 static int __init set_no_mwait(const struct dmi_system_id *id)
25 printk(KERN_NOTICE PREFIX "%s detected - "
26 "disabling mwait for CPU C-states\n", id->ident);
27 boot_option_idle_override = IDLE_NOMWAIT;
31 static struct dmi_system_id __initdata processor_idle_dmi_table[] = {
33 set_no_mwait, "Extensa 5220", {
34 DMI_MATCH(DMI_BIOS_VENDOR, "Phoenix Technologies LTD"),
35 DMI_MATCH(DMI_SYS_VENDOR, "Acer"),
36 DMI_MATCH(DMI_PRODUCT_VERSION, "0100"),
37 DMI_MATCH(DMI_BOARD_NAME, "Columbia") }, NULL},
41 static int map_lapic_id(struct acpi_subtable_header *entry,
42 u32 acpi_id, int *apic_id)
44 struct acpi_madt_local_apic *lapic =
45 (struct acpi_madt_local_apic *)entry;
47 if (!(lapic->lapic_flags & ACPI_MADT_ENABLED))
50 if (lapic->processor_id != acpi_id)
57 static int map_x2apic_id(struct acpi_subtable_header *entry,
58 int device_declaration, u32 acpi_id, int *apic_id)
60 struct acpi_madt_local_x2apic *apic =
61 (struct acpi_madt_local_x2apic *)entry;
63 if (!(apic->lapic_flags & ACPI_MADT_ENABLED))
66 if (device_declaration && (apic->uid == acpi_id)) {
67 *apic_id = apic->local_apic_id;
74 static int map_lsapic_id(struct acpi_subtable_header *entry,
75 int device_declaration, u32 acpi_id, int *apic_id)
77 struct acpi_madt_local_sapic *lsapic =
78 (struct acpi_madt_local_sapic *)entry;
80 if (!(lsapic->lapic_flags & ACPI_MADT_ENABLED))
83 if (device_declaration) {
84 if ((entry->length < 16) || (lsapic->uid != acpi_id))
86 } else if (lsapic->processor_id != acpi_id)
89 *apic_id = (lsapic->id << 8) | lsapic->eid;
93 static int map_madt_entry(int type, u32 acpi_id)
95 unsigned long madt_end, entry;
96 static struct acpi_table_madt *madt;
101 if (ACPI_FAILURE(acpi_get_table(ACPI_SIG_MADT, 0,
102 (struct acpi_table_header **)&madt)))
110 entry = (unsigned long)madt;
111 madt_end = entry + madt->header.length;
113 /* Parse all entries looking for a match. */
115 entry += sizeof(struct acpi_table_madt);
116 while (entry + sizeof(struct acpi_subtable_header) < madt_end) {
117 struct acpi_subtable_header *header =
118 (struct acpi_subtable_header *)entry;
119 if (header->type == ACPI_MADT_TYPE_LOCAL_APIC) {
120 if (map_lapic_id(header, acpi_id, &apic_id))
122 } else if (header->type == ACPI_MADT_TYPE_LOCAL_X2APIC) {
123 if (map_x2apic_id(header, type, acpi_id, &apic_id))
125 } else if (header->type == ACPI_MADT_TYPE_LOCAL_SAPIC) {
126 if (map_lsapic_id(header, type, acpi_id, &apic_id))
129 entry += header->length;
134 static int map_mat_entry(acpi_handle handle, int type, u32 acpi_id)
136 struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
137 union acpi_object *obj;
138 struct acpi_subtable_header *header;
141 if (ACPI_FAILURE(acpi_evaluate_object(handle, "_MAT", NULL, &buffer)))
144 if (!buffer.length || !buffer.pointer)
147 obj = buffer.pointer;
148 if (obj->type != ACPI_TYPE_BUFFER ||
149 obj->buffer.length < sizeof(struct acpi_subtable_header)) {
153 header = (struct acpi_subtable_header *)obj->buffer.pointer;
154 if (header->type == ACPI_MADT_TYPE_LOCAL_APIC) {
155 map_lapic_id(header, acpi_id, &apic_id);
156 } else if (header->type == ACPI_MADT_TYPE_LOCAL_SAPIC) {
157 map_lsapic_id(header, type, acpi_id, &apic_id);
162 kfree(buffer.pointer);
166 int acpi_get_cpuid(acpi_handle handle, int type, u32 acpi_id)
173 apic_id = map_mat_entry(handle, type, acpi_id);
175 apic_id = map_madt_entry(type, acpi_id);
178 * On UP processor, there is no _MAT or MADT table.
179 * So above apic_id is always set to -1.
181 * BIOS may define multiple CPU handles even for UP processor.
186 * Processor (CPU0, 0x00, 0x00000410, 0x06) {}
187 * Processor (CPU1, 0x01, 0x00000410, 0x06) {}
188 * Processor (CPU2, 0x02, 0x00000410, 0x06) {}
189 * Processor (CPU3, 0x03, 0x00000410, 0x06) {}
192 * Ignores apic_id and always returns 0 for the processor
193 * handle with acpi id 0 if nr_cpu_ids is 1.
194 * This should be the case if SMP tables are not found.
195 * Return -1 for other CPU's handle.
197 if (nr_cpu_ids <= 1 && acpi_id == 0)
204 for_each_possible_cpu(i) {
205 if (cpu_physical_id(i) == apic_id)
209 /* In UP kernel, only processor 0 is valid */
215 EXPORT_SYMBOL_GPL(acpi_get_cpuid);
217 static bool __init processor_physically_present(acpi_handle handle)
222 acpi_object_type acpi_type;
223 unsigned long long tmp;
224 union acpi_object object = { 0 };
225 struct acpi_buffer buffer = { sizeof(union acpi_object), &object };
227 status = acpi_get_type(handle, &acpi_type);
228 if (ACPI_FAILURE(status))
232 case ACPI_TYPE_PROCESSOR:
233 status = acpi_evaluate_object(handle, NULL, NULL, &buffer);
234 if (ACPI_FAILURE(status))
236 acpi_id = object.processor.proc_id;
238 case ACPI_TYPE_DEVICE:
239 status = acpi_evaluate_integer(handle, "_UID", NULL, &tmp);
240 if (ACPI_FAILURE(status))
248 type = (acpi_type == ACPI_TYPE_DEVICE) ? 1 : 0;
249 cpuid = acpi_get_cpuid(handle, type, acpi_id);
257 static void __cpuinit acpi_set_pdc_bits(u32 *buf)
259 buf[0] = ACPI_PDC_REVISION_ID;
262 /* Enable coordination with firmware's _TSD info */
263 buf[2] = ACPI_PDC_SMP_T_SWCOORD;
265 /* Twiddle arch-specific bits needed for _PDC */
266 arch_acpi_set_pdc_bits(buf);
269 static struct acpi_object_list *__cpuinit acpi_processor_alloc_pdc(void)
271 struct acpi_object_list *obj_list;
272 union acpi_object *obj;
275 /* allocate and initialize pdc. It will be used later. */
276 obj_list = kmalloc(sizeof(struct acpi_object_list), GFP_KERNEL);
278 printk(KERN_ERR "Memory allocation error\n");
282 obj = kmalloc(sizeof(union acpi_object), GFP_KERNEL);
284 printk(KERN_ERR "Memory allocation error\n");
289 buf = kmalloc(12, GFP_KERNEL);
291 printk(KERN_ERR "Memory allocation error\n");
297 acpi_set_pdc_bits(buf);
299 obj->type = ACPI_TYPE_BUFFER;
300 obj->buffer.length = 12;
301 obj->buffer.pointer = (u8 *) buf;
303 obj_list->pointer = obj;
309 * _PDC is required for a BIOS-OS handshake for most of the newer
310 * ACPI processor features.
313 acpi_processor_eval_pdc(acpi_handle handle, struct acpi_object_list *pdc_in)
315 acpi_status status = AE_OK;
317 if (boot_option_idle_override == IDLE_NOMWAIT) {
319 * If mwait is disabled for CPU C-states, the C2C3_FFH access
320 * mode will be disabled in the parameter of _PDC object.
321 * Of course C1_FFH access mode will also be disabled.
323 union acpi_object *obj;
326 obj = pdc_in->pointer;
327 buffer = (u32 *)(obj->buffer.pointer);
328 buffer[2] &= ~(ACPI_PDC_C_C2C3_FFH | ACPI_PDC_C_C1_FFH);
331 status = acpi_evaluate_object(handle, "_PDC", pdc_in, NULL);
333 if (ACPI_FAILURE(status))
334 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
335 "Could not evaluate _PDC, using legacy perf. control.\n"));
340 void __cpuinit acpi_processor_set_pdc(acpi_handle handle)
342 struct acpi_object_list *obj_list;
344 if (arch_has_acpi_pdc() == false)
347 obj_list = acpi_processor_alloc_pdc();
351 acpi_processor_eval_pdc(handle, obj_list);
353 kfree(obj_list->pointer->buffer.pointer);
354 kfree(obj_list->pointer);
358 static acpi_status __init
359 early_init_pdc(acpi_handle handle, u32 lvl, void *context, void **rv)
361 if (processor_physically_present(handle) == false)
364 acpi_processor_set_pdc(handle);
368 void __init acpi_early_processor_set_pdc(void)
371 * Check whether the system is DMI table. If yes, OSPM
372 * should not use mwait for CPU-states.
374 dmi_check_system(processor_idle_dmi_table);
376 acpi_walk_namespace(ACPI_TYPE_PROCESSOR, ACPI_ROOT_OBJECT,
378 early_init_pdc, NULL, NULL, NULL);
379 acpi_get_devices("ACPI0007", early_init_pdc, NULL, NULL);