Revert "ARM: tegra: tegratab: dummy change"
[linux-2.6.git] / drivers / acpi / processor_core.c
1 /*
2  * Copyright (C) 2005 Intel Corporation
3  * Copyright (C) 2009 Hewlett-Packard Development Company, L.P.
4  *
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/export.h>
11 #include <linux/dmi.h>
12 #include <linux/slab.h>
13
14 #include <acpi/acpi_drivers.h>
15 #include <acpi/processor.h>
16
17 #include "internal.h"
18
19 #define PREFIX                  "ACPI: "
20 #define _COMPONENT              ACPI_PROCESSOR_COMPONENT
21 ACPI_MODULE_NAME("processor_core");
22
23 static int __init set_no_mwait(const struct dmi_system_id *id)
24 {
25         printk(KERN_NOTICE PREFIX "%s detected - "
26                 "disabling mwait for CPU C-states\n", id->ident);
27         boot_option_idle_override = IDLE_NOMWAIT;
28         return 0;
29 }
30
31 static struct dmi_system_id __initdata processor_idle_dmi_table[] = {
32         {
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},
38         {},
39 };
40
41 static int map_lapic_id(struct acpi_subtable_header *entry,
42                  u32 acpi_id, int *apic_id)
43 {
44         struct acpi_madt_local_apic *lapic =
45                 (struct acpi_madt_local_apic *)entry;
46
47         if (!(lapic->lapic_flags & ACPI_MADT_ENABLED))
48                 return 0;
49
50         if (lapic->processor_id != acpi_id)
51                 return 0;
52
53         *apic_id = lapic->id;
54         return 1;
55 }
56
57 static int map_x2apic_id(struct acpi_subtable_header *entry,
58                          int device_declaration, u32 acpi_id, int *apic_id)
59 {
60         struct acpi_madt_local_x2apic *apic =
61                 (struct acpi_madt_local_x2apic *)entry;
62
63         if (!(apic->lapic_flags & ACPI_MADT_ENABLED))
64                 return 0;
65
66         if (device_declaration && (apic->uid == acpi_id)) {
67                 *apic_id = apic->local_apic_id;
68                 return 1;
69         }
70
71         return 0;
72 }
73
74 static int map_lsapic_id(struct acpi_subtable_header *entry,
75                 int device_declaration, u32 acpi_id, int *apic_id)
76 {
77         struct acpi_madt_local_sapic *lsapic =
78                 (struct acpi_madt_local_sapic *)entry;
79
80         if (!(lsapic->lapic_flags & ACPI_MADT_ENABLED))
81                 return 0;
82
83         if (device_declaration) {
84                 if ((entry->length < 16) || (lsapic->uid != acpi_id))
85                         return 0;
86         } else if (lsapic->processor_id != acpi_id)
87                 return 0;
88
89         *apic_id = (lsapic->id << 8) | lsapic->eid;
90         return 1;
91 }
92
93 static int map_madt_entry(int type, u32 acpi_id)
94 {
95         unsigned long madt_end, entry;
96         static struct acpi_table_madt *madt;
97         static int read_madt;
98         int apic_id = -1;
99
100         if (!read_madt) {
101                 if (ACPI_FAILURE(acpi_get_table(ACPI_SIG_MADT, 0,
102                                         (struct acpi_table_header **)&madt)))
103                         madt = NULL;
104                 read_madt++;
105         }
106
107         if (!madt)
108                 return apic_id;
109
110         entry = (unsigned long)madt;
111         madt_end = entry + madt->header.length;
112
113         /* Parse all entries looking for a match. */
114
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))
121                                 break;
122                 } else if (header->type == ACPI_MADT_TYPE_LOCAL_X2APIC) {
123                         if (map_x2apic_id(header, type, acpi_id, &apic_id))
124                                 break;
125                 } else if (header->type == ACPI_MADT_TYPE_LOCAL_SAPIC) {
126                         if (map_lsapic_id(header, type, acpi_id, &apic_id))
127                                 break;
128                 }
129                 entry += header->length;
130         }
131         return apic_id;
132 }
133
134 static int map_mat_entry(acpi_handle handle, int type, u32 acpi_id)
135 {
136         struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
137         union acpi_object *obj;
138         struct acpi_subtable_header *header;
139         int apic_id = -1;
140
141         if (ACPI_FAILURE(acpi_evaluate_object(handle, "_MAT", NULL, &buffer)))
142                 goto exit;
143
144         if (!buffer.length || !buffer.pointer)
145                 goto exit;
146
147         obj = buffer.pointer;
148         if (obj->type != ACPI_TYPE_BUFFER ||
149             obj->buffer.length < sizeof(struct acpi_subtable_header)) {
150                 goto exit;
151         }
152
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);
158         }
159
160 exit:
161         if (buffer.pointer)
162                 kfree(buffer.pointer);
163         return apic_id;
164 }
165
166 int acpi_get_cpuid(acpi_handle handle, int type, u32 acpi_id)
167 {
168 #ifdef CONFIG_SMP
169         int i;
170 #endif
171         int apic_id = -1;
172
173         apic_id = map_mat_entry(handle, type, acpi_id);
174         if (apic_id == -1)
175                 apic_id = map_madt_entry(type, acpi_id);
176         if (apic_id == -1) {
177                 /*
178                  * On UP processor, there is no _MAT or MADT table.
179                  * So above apic_id is always set to -1.
180                  *
181                  * BIOS may define multiple CPU handles even for UP processor.
182                  * For example,
183                  *
184                  * Scope (_PR)
185                  * {
186                  *     Processor (CPU0, 0x00, 0x00000410, 0x06) {}
187                  *     Processor (CPU1, 0x01, 0x00000410, 0x06) {}
188                  *     Processor (CPU2, 0x02, 0x00000410, 0x06) {}
189                  *     Processor (CPU3, 0x03, 0x00000410, 0x06) {}
190                  * }
191                  *
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.
196                  */
197                 if (nr_cpu_ids <= 1 && acpi_id == 0)
198                         return acpi_id;
199                 else
200                         return apic_id;
201         }
202
203 #ifdef CONFIG_SMP
204         for_each_possible_cpu(i) {
205                 if (cpu_physical_id(i) == apic_id)
206                         return i;
207         }
208 #else
209         /* In UP kernel, only processor 0 is valid */
210         if (apic_id == 0)
211                 return apic_id;
212 #endif
213         return -1;
214 }
215 EXPORT_SYMBOL_GPL(acpi_get_cpuid);
216
217 static bool __init processor_physically_present(acpi_handle handle)
218 {
219         int cpuid, type;
220         u32 acpi_id;
221         acpi_status status;
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 };
226
227         status = acpi_get_type(handle, &acpi_type);
228         if (ACPI_FAILURE(status))
229                 return false;
230
231         switch (acpi_type) {
232         case ACPI_TYPE_PROCESSOR:
233                 status = acpi_evaluate_object(handle, NULL, NULL, &buffer);
234                 if (ACPI_FAILURE(status))
235                         return false;
236                 acpi_id = object.processor.proc_id;
237                 break;
238         case ACPI_TYPE_DEVICE:
239                 status = acpi_evaluate_integer(handle, "_UID", NULL, &tmp);
240                 if (ACPI_FAILURE(status))
241                         return false;
242                 acpi_id = tmp;
243                 break;
244         default:
245                 return false;
246         }
247
248         type = (acpi_type == ACPI_TYPE_DEVICE) ? 1 : 0;
249         cpuid = acpi_get_cpuid(handle, type, acpi_id);
250
251         if (cpuid == -1)
252                 return false;
253
254         return true;
255 }
256
257 static void __cpuinit acpi_set_pdc_bits(u32 *buf)
258 {
259         buf[0] = ACPI_PDC_REVISION_ID;
260         buf[1] = 1;
261
262         /* Enable coordination with firmware's _TSD info */
263         buf[2] = ACPI_PDC_SMP_T_SWCOORD;
264
265         /* Twiddle arch-specific bits needed for _PDC */
266         arch_acpi_set_pdc_bits(buf);
267 }
268
269 static struct acpi_object_list *__cpuinit acpi_processor_alloc_pdc(void)
270 {
271         struct acpi_object_list *obj_list;
272         union acpi_object *obj;
273         u32 *buf;
274
275         /* allocate and initialize pdc. It will be used later. */
276         obj_list = kmalloc(sizeof(struct acpi_object_list), GFP_KERNEL);
277         if (!obj_list) {
278                 printk(KERN_ERR "Memory allocation error\n");
279                 return NULL;
280         }
281
282         obj = kmalloc(sizeof(union acpi_object), GFP_KERNEL);
283         if (!obj) {
284                 printk(KERN_ERR "Memory allocation error\n");
285                 kfree(obj_list);
286                 return NULL;
287         }
288
289         buf = kmalloc(12, GFP_KERNEL);
290         if (!buf) {
291                 printk(KERN_ERR "Memory allocation error\n");
292                 kfree(obj);
293                 kfree(obj_list);
294                 return NULL;
295         }
296
297         acpi_set_pdc_bits(buf);
298
299         obj->type = ACPI_TYPE_BUFFER;
300         obj->buffer.length = 12;
301         obj->buffer.pointer = (u8 *) buf;
302         obj_list->count = 1;
303         obj_list->pointer = obj;
304
305         return obj_list;
306 }
307
308 /*
309  * _PDC is required for a BIOS-OS handshake for most of the newer
310  * ACPI processor features.
311  */
312 static int __cpuinit
313 acpi_processor_eval_pdc(acpi_handle handle, struct acpi_object_list *pdc_in)
314 {
315         acpi_status status = AE_OK;
316
317         if (boot_option_idle_override == IDLE_NOMWAIT) {
318                 /*
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.
322                  */
323                 union acpi_object *obj;
324                 u32 *buffer = NULL;
325
326                 obj = pdc_in->pointer;
327                 buffer = (u32 *)(obj->buffer.pointer);
328                 buffer[2] &= ~(ACPI_PDC_C_C2C3_FFH | ACPI_PDC_C_C1_FFH);
329
330         }
331         status = acpi_evaluate_object(handle, "_PDC", pdc_in, NULL);
332
333         if (ACPI_FAILURE(status))
334                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
335                     "Could not evaluate _PDC, using legacy perf. control.\n"));
336
337         return status;
338 }
339
340 void __cpuinit acpi_processor_set_pdc(acpi_handle handle)
341 {
342         struct acpi_object_list *obj_list;
343
344         if (arch_has_acpi_pdc() == false)
345                 return;
346
347         obj_list = acpi_processor_alloc_pdc();
348         if (!obj_list)
349                 return;
350
351         acpi_processor_eval_pdc(handle, obj_list);
352
353         kfree(obj_list->pointer->buffer.pointer);
354         kfree(obj_list->pointer);
355         kfree(obj_list);
356 }
357
358 static acpi_status __init
359 early_init_pdc(acpi_handle handle, u32 lvl, void *context, void **rv)
360 {
361         if (processor_physically_present(handle) == false)
362                 return AE_OK;
363
364         acpi_processor_set_pdc(handle);
365         return AE_OK;
366 }
367
368 void __init acpi_early_processor_set_pdc(void)
369 {
370         /*
371          * Check whether the system is DMI table. If yes, OSPM
372          * should not use mwait for CPU-states.
373          */
374         dmi_check_system(processor_idle_dmi_table);
375
376         acpi_walk_namespace(ACPI_TYPE_PROCESSOR, ACPI_ROOT_OBJECT,
377                             ACPI_UINT32_MAX,
378                             early_init_pdc, NULL, NULL, NULL);
379         acpi_get_devices("ACPI0007", early_init_pdc, NULL, NULL);
380 }