ACPI: processor: refactor internal map_lsapic_id()
[safe/jmp/linux-2.6] / 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/dmi.h>
11
12 #include <acpi/acpi_drivers.h>
13 #include <acpi/processor.h>
14
15 #include "internal.h"
16
17 #define PREFIX                  "ACPI: "
18 #define _COMPONENT              ACPI_PROCESSOR_COMPONENT
19 ACPI_MODULE_NAME("processor_core");
20
21 static int set_no_mwait(const struct dmi_system_id *id)
22 {
23         printk(KERN_NOTICE PREFIX "%s detected - "
24                 "disabling mwait for CPU C-states\n", id->ident);
25         idle_nomwait = 1;
26         return 0;
27 }
28
29 static struct dmi_system_id __cpuinitdata processor_idle_dmi_table[] = {
30         {
31         set_no_mwait, "IFL91 board", {
32         DMI_MATCH(DMI_BIOS_VENDOR, "COMPAL"),
33         DMI_MATCH(DMI_SYS_VENDOR, "ZEPTO"),
34         DMI_MATCH(DMI_PRODUCT_VERSION, "3215W"),
35         DMI_MATCH(DMI_BOARD_NAME, "IFL91") }, NULL},
36         {
37         set_no_mwait, "Extensa 5220", {
38         DMI_MATCH(DMI_BIOS_VENDOR, "Phoenix Technologies LTD"),
39         DMI_MATCH(DMI_SYS_VENDOR, "Acer"),
40         DMI_MATCH(DMI_PRODUCT_VERSION, "0100"),
41         DMI_MATCH(DMI_BOARD_NAME, "Columbia") }, NULL},
42         {},
43 };
44
45 #ifdef CONFIG_SMP
46 static struct acpi_table_madt *madt;
47
48 static int map_lapic_id(struct acpi_subtable_header *entry,
49                  u32 acpi_id, int *apic_id)
50 {
51         struct acpi_madt_local_apic *lapic =
52                 (struct acpi_madt_local_apic *)entry;
53
54         if (!(lapic->lapic_flags & ACPI_MADT_ENABLED))
55                 return 0;
56
57         if (lapic->processor_id != acpi_id)
58                 return 0;
59
60         *apic_id = lapic->id;
61         return 1;
62 }
63
64 static int map_x2apic_id(struct acpi_subtable_header *entry,
65                          int device_declaration, u32 acpi_id, int *apic_id)
66 {
67         struct acpi_madt_local_x2apic *apic =
68                 (struct acpi_madt_local_x2apic *)entry;
69
70         if (!(apic->lapic_flags & ACPI_MADT_ENABLED))
71                 return 0;
72
73         if (device_declaration && (apic->uid == acpi_id)) {
74                 *apic_id = apic->local_apic_id;
75                 return 1;
76         }
77
78         return 0;
79 }
80
81 static int map_lsapic_id(struct acpi_subtable_header *entry,
82                 int device_declaration, u32 acpi_id, int *apic_id)
83 {
84         struct acpi_madt_local_sapic *lsapic =
85                 (struct acpi_madt_local_sapic *)entry;
86
87         if (!(lsapic->lapic_flags & ACPI_MADT_ENABLED))
88                 return 0;
89
90         if (device_declaration) {
91                 if ((entry->length < 16) || (lsapic->uid != acpi_id))
92                         return 0;
93         } else if (lsapic->processor_id != acpi_id)
94                 return 0;
95
96         *apic_id = (lsapic->id << 8) | lsapic->eid;
97         return 1;
98 }
99
100 static int map_madt_entry(int type, u32 acpi_id)
101 {
102         unsigned long madt_end, entry;
103         int apic_id = -1;
104
105         if (!madt)
106                 return apic_id;
107
108         entry = (unsigned long)madt;
109         madt_end = entry + madt->header.length;
110
111         /* Parse all entries looking for a match. */
112
113         entry += sizeof(struct acpi_table_madt);
114         while (entry + sizeof(struct acpi_subtable_header) < madt_end) {
115                 struct acpi_subtable_header *header =
116                         (struct acpi_subtable_header *)entry;
117                 if (header->type == ACPI_MADT_TYPE_LOCAL_APIC) {
118                         if (map_lapic_id(header, acpi_id, &apic_id))
119                                 break;
120                 } else if (header->type == ACPI_MADT_TYPE_LOCAL_X2APIC) {
121                         if (map_x2apic_id(header, type, acpi_id, &apic_id))
122                                 break;
123                 } else if (header->type == ACPI_MADT_TYPE_LOCAL_SAPIC) {
124                         if (map_lsapic_id(header, type, acpi_id, &apic_id))
125                                 break;
126                 }
127                 entry += header->length;
128         }
129         return apic_id;
130 }
131
132 static int map_mat_entry(acpi_handle handle, int type, u32 acpi_id)
133 {
134         struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
135         union acpi_object *obj;
136         struct acpi_subtable_header *header;
137         int apic_id = -1;
138
139         if (ACPI_FAILURE(acpi_evaluate_object(handle, "_MAT", NULL, &buffer)))
140                 goto exit;
141
142         if (!buffer.length || !buffer.pointer)
143                 goto exit;
144
145         obj = buffer.pointer;
146         if (obj->type != ACPI_TYPE_BUFFER ||
147             obj->buffer.length < sizeof(struct acpi_subtable_header)) {
148                 goto exit;
149         }
150
151         header = (struct acpi_subtable_header *)obj->buffer.pointer;
152         if (header->type == ACPI_MADT_TYPE_LOCAL_APIC) {
153                 map_lapic_id(header, acpi_id, &apic_id);
154         } else if (header->type == ACPI_MADT_TYPE_LOCAL_SAPIC) {
155                 map_lsapic_id(header, type, acpi_id, &apic_id);
156         }
157
158 exit:
159         if (buffer.pointer)
160                 kfree(buffer.pointer);
161         return apic_id;
162 }
163
164 int acpi_get_cpuid(acpi_handle handle, int type, u32 acpi_id)
165 {
166         int i;
167         int apic_id = -1;
168
169         apic_id = map_mat_entry(handle, type, acpi_id);
170         if (apic_id == -1)
171                 apic_id = map_madt_entry(type, acpi_id);
172         if (apic_id == -1)
173                 return apic_id;
174
175         for_each_possible_cpu(i) {
176                 if (cpu_physical_id(i) == apic_id)
177                         return i;
178         }
179         return -1;
180 }
181 EXPORT_SYMBOL_GPL(acpi_get_cpuid);
182 #endif
183
184 static bool processor_physically_present(acpi_handle handle)
185 {
186         int cpuid, type;
187         u32 acpi_id;
188         acpi_status status;
189         acpi_object_type acpi_type;
190         unsigned long long tmp;
191         union acpi_object object = { 0 };
192         struct acpi_buffer buffer = { sizeof(union acpi_object), &object };
193
194         status = acpi_get_type(handle, &acpi_type);
195         if (ACPI_FAILURE(status))
196                 return false;
197
198         switch (acpi_type) {
199         case ACPI_TYPE_PROCESSOR:
200                 status = acpi_evaluate_object(handle, NULL, NULL, &buffer);
201                 if (ACPI_FAILURE(status))
202                         return false;
203                 acpi_id = object.processor.proc_id;
204                 break;
205         case ACPI_TYPE_DEVICE:
206                 status = acpi_evaluate_integer(handle, "_UID", NULL, &tmp);
207                 if (ACPI_FAILURE(status))
208                         return false;
209                 acpi_id = tmp;
210                 break;
211         default:
212                 return false;
213         }
214
215         type = (acpi_type == ACPI_TYPE_DEVICE) ? 1 : 0;
216         cpuid = acpi_get_cpuid(handle, type, acpi_id);
217
218         if (cpuid == -1)
219                 return false;
220
221         return true;
222 }
223
224 static void acpi_set_pdc_bits(u32 *buf)
225 {
226         buf[0] = ACPI_PDC_REVISION_ID;
227         buf[1] = 1;
228
229         /* Enable coordination with firmware's _TSD info */
230         buf[2] = ACPI_PDC_SMP_T_SWCOORD;
231
232         /* Twiddle arch-specific bits needed for _PDC */
233         arch_acpi_set_pdc_bits(buf);
234 }
235
236 static struct acpi_object_list *acpi_processor_alloc_pdc(void)
237 {
238         struct acpi_object_list *obj_list;
239         union acpi_object *obj;
240         u32 *buf;
241
242         /* allocate and initialize pdc. It will be used later. */
243         obj_list = kmalloc(sizeof(struct acpi_object_list), GFP_KERNEL);
244         if (!obj_list) {
245                 printk(KERN_ERR "Memory allocation error\n");
246                 return NULL;
247         }
248
249         obj = kmalloc(sizeof(union acpi_object), GFP_KERNEL);
250         if (!obj) {
251                 printk(KERN_ERR "Memory allocation error\n");
252                 kfree(obj_list);
253                 return NULL;
254         }
255
256         buf = kmalloc(12, GFP_KERNEL);
257         if (!buf) {
258                 printk(KERN_ERR "Memory allocation error\n");
259                 kfree(obj);
260                 kfree(obj_list);
261                 return NULL;
262         }
263
264         acpi_set_pdc_bits(buf);
265
266         obj->type = ACPI_TYPE_BUFFER;
267         obj->buffer.length = 12;
268         obj->buffer.pointer = (u8 *) buf;
269         obj_list->count = 1;
270         obj_list->pointer = obj;
271
272         return obj_list;
273 }
274
275 /*
276  * _PDC is required for a BIOS-OS handshake for most of the newer
277  * ACPI processor features.
278  */
279 static int
280 acpi_processor_eval_pdc(acpi_handle handle, struct acpi_object_list *pdc_in)
281 {
282         acpi_status status = AE_OK;
283
284         if (idle_nomwait) {
285                 /*
286                  * If mwait is disabled for CPU C-states, the C2C3_FFH access
287                  * mode will be disabled in the parameter of _PDC object.
288                  * Of course C1_FFH access mode will also be disabled.
289                  */
290                 union acpi_object *obj;
291                 u32 *buffer = NULL;
292
293                 obj = pdc_in->pointer;
294                 buffer = (u32 *)(obj->buffer.pointer);
295                 buffer[2] &= ~(ACPI_PDC_C_C2C3_FFH | ACPI_PDC_C_C1_FFH);
296
297         }
298         status = acpi_evaluate_object(handle, "_PDC", pdc_in, NULL);
299
300         if (ACPI_FAILURE(status))
301                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
302                     "Could not evaluate _PDC, using legacy perf. control.\n"));
303
304         return status;
305 }
306
307 void acpi_processor_set_pdc(acpi_handle handle)
308 {
309         struct acpi_object_list *obj_list;
310
311         if (arch_has_acpi_pdc() == false)
312                 return;
313
314         obj_list = acpi_processor_alloc_pdc();
315         if (!obj_list)
316                 return;
317
318         acpi_processor_eval_pdc(handle, obj_list);
319
320         kfree(obj_list->pointer->buffer.pointer);
321         kfree(obj_list->pointer);
322         kfree(obj_list);
323 }
324 EXPORT_SYMBOL_GPL(acpi_processor_set_pdc);
325
326 static acpi_status
327 early_init_pdc(acpi_handle handle, u32 lvl, void *context, void **rv)
328 {
329         if (processor_physically_present(handle) == false)
330                 return AE_OK;
331
332         acpi_processor_set_pdc(handle);
333         return AE_OK;
334 }
335
336 void __init acpi_early_processor_set_pdc(void)
337 {
338
339 #ifdef CONFIG_SMP
340         if (ACPI_FAILURE(acpi_get_table(ACPI_SIG_MADT, 0,
341                                 (struct acpi_table_header **)&madt)))
342                 madt = NULL;
343 #endif
344
345         /*
346          * Check whether the system is DMI table. If yes, OSPM
347          * should not use mwait for CPU-states.
348          */
349         dmi_check_system(processor_idle_dmi_table);
350
351         acpi_walk_namespace(ACPI_TYPE_PROCESSOR, ACPI_ROOT_OBJECT,
352                             ACPI_UINT32_MAX,
353                             early_init_pdc, NULL, NULL, NULL);
354 }