summaryrefslogtreecommitdiffstats
path: root/drivers/acpi/processor_core.c
blob: a5e9f4a5b2816a9473942b229bc4632ec640bf5c (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
/*
 * Copyright (C) 2005 Intel Corporation
 * Copyright (C) 2009 Hewlett-Packard Development Company, L.P.
 *
 *	Alex Chiang <achiang@hp.com>
 *	- Unified x86/ia64 implementations
 *	Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
 *	- Added _PDC for platforms with Intel CPUs
 */
#include <linux/export.h>
#include <linux/dmi.h>
#include <linux/slab.h>

#include <acpi/acpi_drivers.h>
#include <acpi/processor.h>

#include "internal.h"

#define PREFIX			"ACPI: "
#define _COMPONENT		ACPI_PROCESSOR_COMPONENT
ACPI_MODULE_NAME("processor_core");

static int __init set_no_mwait(const struct dmi_system_id *id)
{
	printk(KERN_NOTICE PREFIX "%s detected - "
		"disabling mwait for CPU C-states\n", id->ident);
	boot_option_idle_override = IDLE_NOMWAIT;
	return 0;
}

static struct dmi_system_id __initdata processor_idle_dmi_table[] = {
	{
	set_no_mwait, "Extensa 5220", {
	DMI_MATCH(DMI_BIOS_VENDOR, "Phoenix Technologies LTD"),
	DMI_MATCH(DMI_SYS_VENDOR, "Acer"),
	DMI_MATCH(DMI_PRODUCT_VERSION, "0100"),
	DMI_MATCH(DMI_BOARD_NAME, "Columbia") }, NULL},
	{},
};

static int map_lapic_id(struct acpi_subtable_header *entry,
		 u32 acpi_id, int *apic_id)
{
	struct acpi_madt_local_apic *lapic =
		(struct acpi_madt_local_apic *)entry;

	if (!(lapic->lapic_flags & ACPI_MADT_ENABLED))
		return 0;

	if (lapic->processor_id != acpi_id)
		return 0;

	*apic_id = lapic->id;
	return 1;
}

static int map_x2apic_id(struct acpi_subtable_header *entry,
			 int device_declaration, u32 acpi_id, int *apic_id)
{
	struct acpi_madt_local_x2apic *apic =
		(struct acpi_madt_local_x2apic *)entry;

	if (!(apic->lapic_flags & ACPI_MADT_ENABLED))
		return 0;

	if (device_declaration && (apic->uid == acpi_id)) {
		*apic_id = apic->local_apic_id;
		return 1;
	}

	return 0;
}

static int map_lsapic_id(struct acpi_subtable_header *entry,
		int device_declaration, u32 acpi_id, int *apic_id)
{
	struct acpi_madt_local_sapic *lsapic =
		(struct acpi_madt_local_sapic *)entry;

	if (!(lsapic->lapic_flags & ACPI_MADT_ENABLED))
		return 0;

	if (device_declaration) {
		if ((entry->length < 16) || (lsapic->uid != acpi_id))
			return 0;
	} else if (lsapic->processor_id != acpi_id)
		return 0;

	*apic_id = (lsapic->id << 8) | lsapic->eid;
	return 1;
}

static int map_madt_entry(int type, u32 acpi_id)
{
	unsigned long madt_end, entry;
	static struct acpi_table_madt *madt;
	static int read_madt;
	int apic_id = -1;

	if (!read_madt) {
		if (ACPI_FAILURE(acpi_get_table(ACPI_SIG_MADT, 0,
					(struct acpi_table_header **)&madt)))
			madt = NULL;
		read_madt++;
	}

	if (!madt)
		return apic_id;

	entry = (unsigned long)madt;
	madt_end = entry + madt->header.length;

	/* Parse all entries looking for a match. */

	entry += sizeof(struct acpi_table_madt);
	while (entry + sizeof(struct acpi_subtable_header) < madt_end) {
		struct acpi_subtable_header *header =
			(struct acpi_subtable_header *)entry;
		if (header->type == ACPI_MADT_TYPE_LOCAL_APIC) {
			if (map_lapic_id(header, acpi_id, &apic_id))
				break;
		} else if (header->type == ACPI_MADT_TYPE_LOCAL_X2APIC) {
			if (map_x2apic_id(header, type, acpi_id, &apic_id))
				break;
		} else if (header->type == ACPI_MADT_TYPE_LOCAL_SAPIC) {
			if (map_lsapic_id(header, type, acpi_id, &apic_id))
				break;
		}
		entry += header->length;
	}
	return apic_id;
}

static int map_mat_entry(acpi_handle handle, int type, u32 acpi_id)
{
	struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
	union acpi_object *obj;
	struct acpi_subtable_header *header;
	int apic_id = -1;

	if (ACPI_FAILURE(acpi_evaluate_object(handle, "_MAT", NULL, &buffer)))
		goto exit;

	if (!buffer.length || !buffer.pointer)
		goto exit;

	obj = buffer.pointer;
	if (obj->type != ACPI_TYPE_BUFFER ||
	    obj->buffer.length < sizeof(struct acpi_subtable_header)) {
		goto exit;
	}

	header = (struct acpi_subtable_header *)obj->buffer.pointer;
	if (header->type == ACPI_MADT_TYPE_LOCAL_APIC) {
		map_lapic_id(header, acpi_id, &apic_id);
	} else if (header->type == ACPI_MADT_TYPE_LOCAL_SAPIC) {
		map_lsapic_id(header, type, acpi_id, &apic_id);
	}

exit:
	kfree(buffer.pointer);
	return apic_id;
}

int acpi_get_cpuid(acpi_handle handle, int type, u32 acpi_id)
{
#ifdef CONFIG_SMP
	int i;
#endif
	int apic_id = -1;

	apic_id = map_mat_entry(handle, type, acpi_id);
	if (apic_id == -1)
		apic_id = map_madt_entry(type, acpi_id);
	if (apic_id == -1) {
		/*
		 * On UP processor, there is no _MAT or MADT table.
		 * So above apic_id is always set to -1.
		 *
		 * BIOS may define multiple CPU handles even for UP processor.
		 * For example,
		 *
		 * Scope (_PR)
                 * {
		 *     Processor (CPU0, 0x00, 0x00000410, 0x06) {}
		 *     Processor (CPU1, 0x01, 0x00000410, 0x06) {}
		 *     Processor (CPU2, 0x02, 0x00000410, 0x06) {}
		 *     Processor (CPU3, 0x03, 0x00000410, 0x06) {}
		 * }
		 *
		 * Ignores apic_id and always returns 0 for the processor
		 * handle with acpi id 0 if nr_cpu_ids is 1.
		 * This should be the case if SMP tables are not found.
		 * Return -1 for other CPU's handle.
		 */
		if (nr_cpu_ids <= 1 && acpi_id == 0)
			return acpi_id;
		else
			return apic_id;
	}

#ifdef CONFIG_SMP
	for_each_possible_cpu(i) {
		if (cpu_physical_id(i) == apic_id)
			return i;
	}
#else
	/* In UP kernel, only processor 0 is valid */
	if (apic_id == 0)
		return apic_id;
#endif
	return -1;
}
EXPORT_SYMBOL_GPL(acpi_get_cpuid);

static bool __init processor_physically_present(acpi_handle handle)
{
	int cpuid, type;
	u32 acpi_id;
	acpi_status status;
	acpi_object_type acpi_type;
	unsigned long long tmp;
	union acpi_object object = { 0 };
	struct acpi_buffer buffer = { sizeof(union acpi_object), &object };

	status = acpi_get_type(handle, &acpi_type);
	if (ACPI_FAILURE(status))
		return false;

	switch (acpi_type) {
	case ACPI_TYPE_PROCESSOR:
		status = acpi_evaluate_object(handle, NULL, NULL, &buffer);
		if (ACPI_FAILURE(status))
			return false;
		acpi_id = object.processor.proc_id;
		break;
	case ACPI_TYPE_DEVICE:
		status = acpi_evaluate_integer(handle, "_UID", NULL, &tmp);
		if (ACPI_FAILURE(status))
			return false;
		acpi_id = tmp;
		break;
	default:
		return false;
	}

	type = (acpi_type == ACPI_TYPE_DEVICE) ? 1 : 0;
	cpuid = acpi_get_cpuid(handle, type, acpi_id);

	if (cpuid == -1)
		return false;

	return true;
}

static void acpi_set_pdc_bits(u32 *buf)
{
	buf[0] = ACPI_PDC_REVISION_ID;
	buf[1] = 1;

	/* Enable coordination with firmware's _TSD info */
	buf[2] = ACPI_PDC_SMP_T_SWCOORD;

	/* Twiddle arch-specific bits needed for _PDC */
	arch_acpi_set_pdc_bits(buf);
}

static struct acpi_object_list *acpi_processor_alloc_pdc(void)
{
	struct acpi_object_list *obj_list;
	union acpi_object *obj;
	u32 *buf;

	/* allocate and initialize pdc. It will be used later. */
	obj_list = kmalloc(sizeof(struct acpi_object_list), GFP_KERNEL);
	if (!obj_list) {
		printk(KERN_ERR "Memory allocation error\n");
		return NULL;
	}

	obj = kmalloc(sizeof(union acpi_object), GFP_KERNEL);
	if (!obj) {
		printk(KERN_ERR "Memory allocation error\n");
		kfree(obj_list);
		return NULL;
	}

	buf = kmalloc(12, GFP_KERNEL);
	if (!buf) {
		printk(KERN_ERR "Memory allocation error\n");
		kfree(obj);
		kfree(obj_list);
		return NULL;
	}

	acpi_set_pdc_bits(buf);

	obj->type = ACPI_TYPE_BUFFER;
	obj->buffer.length = 12;
	obj->buffer.pointer = (u8 *) buf;
	obj_list->count = 1;
	obj_list->pointer = obj;

	return obj_list;
}

/*
 * _PDC is required for a BIOS-OS handshake for most of the newer
 * ACPI processor features.
 */
static int
acpi_processor_eval_pdc(acpi_handle handle, struct acpi_object_list *pdc_in)
{
	acpi_status status = AE_OK;

	if (boot_option_idle_override == IDLE_NOMWAIT) {
		/*
		 * If mwait is disabled for CPU C-states, the C2C3_FFH access
		 * mode will be disabled in the parameter of _PDC object.
		 * Of course C1_FFH access mode will also be disabled.
		 */
		union acpi_object *obj;
		u32 *buffer = NULL;

		obj = pdc_in->pointer;
		buffer = (u32 *)(obj->buffer.pointer);
		buffer[2] &= ~(ACPI_PDC_C_C2C3_FFH | ACPI_PDC_C_C1_FFH);

	}
	status = acpi_evaluate_object(handle, "_PDC", pdc_in, NULL);

	if (ACPI_FAILURE(status))
		ACPI_DEBUG_PRINT((ACPI_DB_INFO,
		    "Could not evaluate _PDC, using legacy perf. control.\n"));

	return status;
}

void acpi_processor_set_pdc(acpi_handle handle)
{
	struct acpi_object_list *obj_list;

	if (arch_has_acpi_pdc() == false)
		return;

	obj_list = acpi_processor_alloc_pdc();
	if (!obj_list)
		return;

	acpi_processor_eval_pdc(handle, obj_list);

	kfree(obj_list->pointer->buffer.pointer);
	kfree(obj_list->pointer);
	kfree(obj_list);
}

static acpi_status __init
early_init_pdc(acpi_handle handle, u32 lvl, void *context, void **rv)
{
	if (processor_physically_present(handle) == false)
		return AE_OK;

	acpi_processor_set_pdc(handle);
	return AE_OK;
}

void __init acpi_early_processor_set_pdc(void)
{
	/*
	 * Check whether the system is DMI table. If yes, OSPM
	 * should not use mwait for CPU-states.
	 */
	dmi_check_system(processor_idle_dmi_table);

	acpi_walk_namespace(ACPI_TYPE_PROCESSOR, ACPI_ROOT_OBJECT,
			    ACPI_UINT32_MAX,
			    early_init_pdc, NULL, NULL, NULL);
	acpi_get_devices("ACPI0007", early_init_pdc, NULL, NULL);
}