hwmon: (coretemp) Fix TjMax detection for older CPUs
[linux-2.6/linux-acpi-2.6/ibm-acpi-2.6.git] / drivers / acpi / processor_core.c
blob02d2a4c9084df510c7f6929d08a7082f1ecba5d8
1 /*
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
9 */
10 #include <linux/dmi.h>
11 #include <linux/slab.h>
13 #include <acpi/acpi_drivers.h>
14 #include <acpi/processor.h>
16 #include "internal.h"
18 #define PREFIX "ACPI: "
19 #define _COMPONENT ACPI_PROCESSOR_COMPONENT
20 ACPI_MODULE_NAME("processor_core");
22 static int __init set_no_mwait(const struct dmi_system_id *id)
24 printk(KERN_NOTICE PREFIX "%s detected - "
25 "disabling mwait for CPU C-states\n", id->ident);
26 boot_option_idle_override = IDLE_NOMWAIT;
27 return 0;
30 static struct dmi_system_id __initdata processor_idle_dmi_table[] = {
32 set_no_mwait, "Extensa 5220", {
33 DMI_MATCH(DMI_BIOS_VENDOR, "Phoenix Technologies LTD"),
34 DMI_MATCH(DMI_SYS_VENDOR, "Acer"),
35 DMI_MATCH(DMI_PRODUCT_VERSION, "0100"),
36 DMI_MATCH(DMI_BOARD_NAME, "Columbia") }, NULL},
37 {},
40 static int map_lapic_id(struct acpi_subtable_header *entry,
41 u32 acpi_id, int *apic_id)
43 struct acpi_madt_local_apic *lapic =
44 (struct acpi_madt_local_apic *)entry;
46 if (!(lapic->lapic_flags & ACPI_MADT_ENABLED))
47 return 0;
49 if (lapic->processor_id != acpi_id)
50 return 0;
52 *apic_id = lapic->id;
53 return 1;
56 static int map_x2apic_id(struct acpi_subtable_header *entry,
57 int device_declaration, u32 acpi_id, int *apic_id)
59 struct acpi_madt_local_x2apic *apic =
60 (struct acpi_madt_local_x2apic *)entry;
62 if (!(apic->lapic_flags & ACPI_MADT_ENABLED))
63 return 0;
65 if (device_declaration && (apic->uid == acpi_id)) {
66 *apic_id = apic->local_apic_id;
67 return 1;
70 return 0;
73 static int map_lsapic_id(struct acpi_subtable_header *entry,
74 int device_declaration, u32 acpi_id, int *apic_id)
76 struct acpi_madt_local_sapic *lsapic =
77 (struct acpi_madt_local_sapic *)entry;
79 if (!(lsapic->lapic_flags & ACPI_MADT_ENABLED))
80 return 0;
82 if (device_declaration) {
83 if ((entry->length < 16) || (lsapic->uid != acpi_id))
84 return 0;
85 } else if (lsapic->processor_id != acpi_id)
86 return 0;
88 *apic_id = (lsapic->id << 8) | lsapic->eid;
89 return 1;
92 static int map_madt_entry(int type, u32 acpi_id)
94 unsigned long madt_end, entry;
95 static struct acpi_table_madt *madt;
96 static int read_madt;
97 int apic_id = -1;
99 if (!read_madt) {
100 if (ACPI_FAILURE(acpi_get_table(ACPI_SIG_MADT, 0,
101 (struct acpi_table_header **)&madt)))
102 madt = NULL;
103 read_madt++;
106 if (!madt)
107 return apic_id;
109 entry = (unsigned long)madt;
110 madt_end = entry + madt->header.length;
112 /* Parse all entries looking for a match. */
114 entry += sizeof(struct acpi_table_madt);
115 while (entry + sizeof(struct acpi_subtable_header) < madt_end) {
116 struct acpi_subtable_header *header =
117 (struct acpi_subtable_header *)entry;
118 if (header->type == ACPI_MADT_TYPE_LOCAL_APIC) {
119 if (map_lapic_id(header, acpi_id, &apic_id))
120 break;
121 } else if (header->type == ACPI_MADT_TYPE_LOCAL_X2APIC) {
122 if (map_x2apic_id(header, type, acpi_id, &apic_id))
123 break;
124 } else if (header->type == ACPI_MADT_TYPE_LOCAL_SAPIC) {
125 if (map_lsapic_id(header, type, acpi_id, &apic_id))
126 break;
128 entry += header->length;
130 return apic_id;
133 static int map_mat_entry(acpi_handle handle, int type, u32 acpi_id)
135 struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
136 union acpi_object *obj;
137 struct acpi_subtable_header *header;
138 int apic_id = -1;
140 if (ACPI_FAILURE(acpi_evaluate_object(handle, "_MAT", NULL, &buffer)))
141 goto exit;
143 if (!buffer.length || !buffer.pointer)
144 goto exit;
146 obj = buffer.pointer;
147 if (obj->type != ACPI_TYPE_BUFFER ||
148 obj->buffer.length < sizeof(struct acpi_subtable_header)) {
149 goto exit;
152 header = (struct acpi_subtable_header *)obj->buffer.pointer;
153 if (header->type == ACPI_MADT_TYPE_LOCAL_APIC) {
154 map_lapic_id(header, acpi_id, &apic_id);
155 } else if (header->type == ACPI_MADT_TYPE_LOCAL_SAPIC) {
156 map_lsapic_id(header, type, acpi_id, &apic_id);
159 exit:
160 if (buffer.pointer)
161 kfree(buffer.pointer);
162 return apic_id;
165 int acpi_get_cpuid(acpi_handle handle, int type, u32 acpi_id)
167 #ifdef CONFIG_SMP
168 int i;
169 #endif
170 int apic_id = -1;
172 apic_id = map_mat_entry(handle, type, acpi_id);
173 if (apic_id == -1)
174 apic_id = map_madt_entry(type, acpi_id);
175 if (apic_id == -1)
176 return apic_id;
178 #ifdef CONFIG_SMP
179 for_each_possible_cpu(i) {
180 if (cpu_physical_id(i) == apic_id)
181 return i;
183 #else
184 /* In UP kernel, only processor 0 is valid */
185 if (apic_id == 0)
186 return apic_id;
187 #endif
188 return -1;
190 EXPORT_SYMBOL_GPL(acpi_get_cpuid);
192 static bool __init processor_physically_present(acpi_handle handle)
194 int cpuid, type;
195 u32 acpi_id;
196 acpi_status status;
197 acpi_object_type acpi_type;
198 unsigned long long tmp;
199 union acpi_object object = { 0 };
200 struct acpi_buffer buffer = { sizeof(union acpi_object), &object };
202 status = acpi_get_type(handle, &acpi_type);
203 if (ACPI_FAILURE(status))
204 return false;
206 switch (acpi_type) {
207 case ACPI_TYPE_PROCESSOR:
208 status = acpi_evaluate_object(handle, NULL, NULL, &buffer);
209 if (ACPI_FAILURE(status))
210 return false;
211 acpi_id = object.processor.proc_id;
212 break;
213 case ACPI_TYPE_DEVICE:
214 status = acpi_evaluate_integer(handle, "_UID", NULL, &tmp);
215 if (ACPI_FAILURE(status))
216 return false;
217 acpi_id = tmp;
218 break;
219 default:
220 return false;
223 type = (acpi_type == ACPI_TYPE_DEVICE) ? 1 : 0;
224 cpuid = acpi_get_cpuid(handle, type, acpi_id);
226 if (cpuid == -1)
227 return false;
229 return true;
232 static void __cpuinit acpi_set_pdc_bits(u32 *buf)
234 buf[0] = ACPI_PDC_REVISION_ID;
235 buf[1] = 1;
237 /* Enable coordination with firmware's _TSD info */
238 buf[2] = ACPI_PDC_SMP_T_SWCOORD;
240 /* Twiddle arch-specific bits needed for _PDC */
241 arch_acpi_set_pdc_bits(buf);
244 static struct acpi_object_list *__cpuinit acpi_processor_alloc_pdc(void)
246 struct acpi_object_list *obj_list;
247 union acpi_object *obj;
248 u32 *buf;
250 /* allocate and initialize pdc. It will be used later. */
251 obj_list = kmalloc(sizeof(struct acpi_object_list), GFP_KERNEL);
252 if (!obj_list) {
253 printk(KERN_ERR "Memory allocation error\n");
254 return NULL;
257 obj = kmalloc(sizeof(union acpi_object), GFP_KERNEL);
258 if (!obj) {
259 printk(KERN_ERR "Memory allocation error\n");
260 kfree(obj_list);
261 return NULL;
264 buf = kmalloc(12, GFP_KERNEL);
265 if (!buf) {
266 printk(KERN_ERR "Memory allocation error\n");
267 kfree(obj);
268 kfree(obj_list);
269 return NULL;
272 acpi_set_pdc_bits(buf);
274 obj->type = ACPI_TYPE_BUFFER;
275 obj->buffer.length = 12;
276 obj->buffer.pointer = (u8 *) buf;
277 obj_list->count = 1;
278 obj_list->pointer = obj;
280 return obj_list;
284 * _PDC is required for a BIOS-OS handshake for most of the newer
285 * ACPI processor features.
287 static int __cpuinit
288 acpi_processor_eval_pdc(acpi_handle handle, struct acpi_object_list *pdc_in)
290 acpi_status status = AE_OK;
292 if (boot_option_idle_override == IDLE_NOMWAIT) {
294 * If mwait is disabled for CPU C-states, the C2C3_FFH access
295 * mode will be disabled in the parameter of _PDC object.
296 * Of course C1_FFH access mode will also be disabled.
298 union acpi_object *obj;
299 u32 *buffer = NULL;
301 obj = pdc_in->pointer;
302 buffer = (u32 *)(obj->buffer.pointer);
303 buffer[2] &= ~(ACPI_PDC_C_C2C3_FFH | ACPI_PDC_C_C1_FFH);
306 status = acpi_evaluate_object(handle, "_PDC", pdc_in, NULL);
308 if (ACPI_FAILURE(status))
309 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
310 "Could not evaluate _PDC, using legacy perf. control.\n"));
312 return status;
315 void __cpuinit acpi_processor_set_pdc(acpi_handle handle)
317 struct acpi_object_list *obj_list;
319 if (arch_has_acpi_pdc() == false)
320 return;
322 obj_list = acpi_processor_alloc_pdc();
323 if (!obj_list)
324 return;
326 acpi_processor_eval_pdc(handle, obj_list);
328 kfree(obj_list->pointer->buffer.pointer);
329 kfree(obj_list->pointer);
330 kfree(obj_list);
333 static acpi_status __init
334 early_init_pdc(acpi_handle handle, u32 lvl, void *context, void **rv)
336 if (processor_physically_present(handle) == false)
337 return AE_OK;
339 acpi_processor_set_pdc(handle);
340 return AE_OK;
343 void __init acpi_early_processor_set_pdc(void)
346 * Check whether the system is DMI table. If yes, OSPM
347 * should not use mwait for CPU-states.
349 dmi_check_system(processor_idle_dmi_table);
351 acpi_walk_namespace(ACPI_TYPE_PROCESSOR, ACPI_ROOT_OBJECT,
352 ACPI_UINT32_MAX,
353 early_init_pdc, NULL, NULL, NULL);
354 acpi_get_devices("ACPI0007", early_init_pdc, NULL, NULL);