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
set_no_mwait(const struct dmi_system_id * id)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
map_lapic_id(struct acpi_subtable_header * entry,u32 acpi_id,int * apic_id)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
map_x2apic_id(struct acpi_subtable_header * entry,int device_declaration,u32 acpi_id,int * apic_id)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
map_lsapic_id(struct acpi_subtable_header * entry,int device_declaration,u32 acpi_id,int * apic_id)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
map_madt_entry(int type,u32 acpi_id)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
map_mat_entry(acpi_handle handle,int type,u32 acpi_id)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
acpi_get_cpuid(acpi_handle handle,int type,u32 acpi_id)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
processor_physically_present(acpi_handle handle)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
acpi_set_pdc_bits(u32 * buf)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
acpi_processor_alloc_pdc(void)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
acpi_processor_eval_pdc(acpi_handle handle,struct acpi_object_list * pdc_in)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
acpi_processor_set_pdc(acpi_handle handle)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
early_init_pdc(acpi_handle handle,u32 lvl,void * context,void ** rv)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
acpi_early_processor_set_pdc(void)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 }
381