processor_core.c revision d67420956b7b1dcffb894b2f1f81b9408fca1b4c 
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
19ACPI_MODULE_NAME("processor_core");
20
21static 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
29static 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
46static struct acpi_table_madt *madt;
47
48static 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
64static 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
81static 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	u32 tmp = (lsapic->id << 8) | lsapic->eid;
87
88	/* Only check enabled APICs*/
89	if (!(lsapic->lapic_flags & ACPI_MADT_ENABLED))
90		return 0;
91
92	/* Device statement declaration type */
93	if (device_declaration) {
94		if (entry->length < 16)
95			printk(KERN_ERR PREFIX
96			    "Invalid LSAPIC with Device type processor (SAPIC ID %#x)\n",
97			    tmp);
98		else if (lsapic->uid == acpi_id)
99			goto found;
100	/* Processor statement declaration type */
101	} else if (lsapic->processor_id == acpi_id)
102		goto found;
103
104	return 0;
105found:
106	*apic_id = tmp;
107	return 1;
108}
109
110static int map_madt_entry(int type, u32 acpi_id)
111{
112	unsigned long madt_end, entry;
113	int apic_id = -1;
114
115	if (!madt)
116		return apic_id;
117
118	entry = (unsigned long)madt;
119	madt_end = entry + madt->header.length;
120
121	/* Parse all entries looking for a match. */
122
123	entry += sizeof(struct acpi_table_madt);
124	while (entry + sizeof(struct acpi_subtable_header) < madt_end) {
125		struct acpi_subtable_header *header =
126			(struct acpi_subtable_header *)entry;
127		if (header->type == ACPI_MADT_TYPE_LOCAL_APIC) {
128			if (map_lapic_id(header, acpi_id, &apic_id))
129				break;
130		} else if (header->type == ACPI_MADT_TYPE_LOCAL_X2APIC) {
131			if (map_x2apic_id(header, type, acpi_id, &apic_id))
132				break;
133		} else if (header->type == ACPI_MADT_TYPE_LOCAL_SAPIC) {
134			if (map_lsapic_id(header, type, acpi_id, &apic_id))
135				break;
136		}
137		entry += header->length;
138	}
139	return apic_id;
140}
141
142static int map_mat_entry(acpi_handle handle, int type, u32 acpi_id)
143{
144	struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
145	union acpi_object *obj;
146	struct acpi_subtable_header *header;
147	int apic_id = -1;
148
149	if (ACPI_FAILURE(acpi_evaluate_object(handle, "_MAT", NULL, &buffer)))
150		goto exit;
151
152	if (!buffer.length || !buffer.pointer)
153		goto exit;
154
155	obj = buffer.pointer;
156	if (obj->type != ACPI_TYPE_BUFFER ||
157	    obj->buffer.length < sizeof(struct acpi_subtable_header)) {
158		goto exit;
159	}
160
161	header = (struct acpi_subtable_header *)obj->buffer.pointer;
162	if (header->type == ACPI_MADT_TYPE_LOCAL_APIC) {
163		map_lapic_id(header, acpi_id, &apic_id);
164	} else if (header->type == ACPI_MADT_TYPE_LOCAL_SAPIC) {
165		map_lsapic_id(header, type, acpi_id, &apic_id);
166	}
167
168exit:
169	if (buffer.pointer)
170		kfree(buffer.pointer);
171	return apic_id;
172}
173
174int acpi_get_cpuid(acpi_handle handle, int type, u32 acpi_id)
175{
176	int i;
177	int apic_id = -1;
178
179	apic_id = map_mat_entry(handle, type, acpi_id);
180	if (apic_id == -1)
181		apic_id = map_madt_entry(type, acpi_id);
182	if (apic_id == -1)
183		return apic_id;
184
185	for_each_possible_cpu(i) {
186		if (cpu_physical_id(i) == apic_id)
187			return i;
188	}
189	return -1;
190}
191EXPORT_SYMBOL_GPL(acpi_get_cpuid);
192#endif
193
194static bool processor_physically_present(acpi_handle handle)
195{
196	int cpuid, type;
197	u32 acpi_id;
198	acpi_status status;
199	acpi_object_type acpi_type;
200	unsigned long long tmp;
201	union acpi_object object = { 0 };
202	struct acpi_buffer buffer = { sizeof(union acpi_object), &object };
203
204	status = acpi_get_type(handle, &acpi_type);
205	if (ACPI_FAILURE(status))
206		return false;
207
208	switch (acpi_type) {
209	case ACPI_TYPE_PROCESSOR:
210		status = acpi_evaluate_object(handle, NULL, NULL, &buffer);
211		if (ACPI_FAILURE(status))
212			return false;
213		acpi_id = object.processor.proc_id;
214		break;
215	case ACPI_TYPE_DEVICE:
216		status = acpi_evaluate_integer(handle, "_UID", NULL, &tmp);
217		if (ACPI_FAILURE(status))
218			return false;
219		acpi_id = tmp;
220		break;
221	default:
222		return false;
223	}
224
225	type = (acpi_type == ACPI_TYPE_DEVICE) ? 1 : 0;
226	cpuid = acpi_get_cpuid(handle, type, acpi_id);
227
228	if (cpuid == -1)
229		return false;
230
231	return true;
232}
233
234static void acpi_set_pdc_bits(u32 *buf)
235{
236	buf[0] = ACPI_PDC_REVISION_ID;
237	buf[1] = 1;
238
239	/* Enable coordination with firmware's _TSD info */
240	buf[2] = ACPI_PDC_SMP_T_SWCOORD;
241
242	/* Twiddle arch-specific bits needed for _PDC */
243	arch_acpi_set_pdc_bits(buf);
244}
245
246static struct acpi_object_list *acpi_processor_alloc_pdc(void)
247{
248	struct acpi_object_list *obj_list;
249	union acpi_object *obj;
250	u32 *buf;
251
252	/* allocate and initialize pdc. It will be used later. */
253	obj_list = kmalloc(sizeof(struct acpi_object_list), GFP_KERNEL);
254	if (!obj_list) {
255		printk(KERN_ERR "Memory allocation error\n");
256		return NULL;
257	}
258
259	obj = kmalloc(sizeof(union acpi_object), GFP_KERNEL);
260	if (!obj) {
261		printk(KERN_ERR "Memory allocation error\n");
262		kfree(obj_list);
263		return NULL;
264	}
265
266	buf = kmalloc(12, GFP_KERNEL);
267	if (!buf) {
268		printk(KERN_ERR "Memory allocation error\n");
269		kfree(obj);
270		kfree(obj_list);
271		return NULL;
272	}
273
274	acpi_set_pdc_bits(buf);
275
276	obj->type = ACPI_TYPE_BUFFER;
277	obj->buffer.length = 12;
278	obj->buffer.pointer = (u8 *) buf;
279	obj_list->count = 1;
280	obj_list->pointer = obj;
281
282	return obj_list;
283}
284
285/*
286 * _PDC is required for a BIOS-OS handshake for most of the newer
287 * ACPI processor features.
288 */
289static int
290acpi_processor_eval_pdc(acpi_handle handle, struct acpi_object_list *pdc_in)
291{
292	acpi_status status = AE_OK;
293
294	if (idle_nomwait) {
295		/*
296		 * If mwait is disabled for CPU C-states, the C2C3_FFH access
297		 * mode will be disabled in the parameter of _PDC object.
298		 * Of course C1_FFH access mode will also be disabled.
299		 */
300		union acpi_object *obj;
301		u32 *buffer = NULL;
302
303		obj = pdc_in->pointer;
304		buffer = (u32 *)(obj->buffer.pointer);
305		buffer[2] &= ~(ACPI_PDC_C_C2C3_FFH | ACPI_PDC_C_C1_FFH);
306
307	}
308	status = acpi_evaluate_object(handle, "_PDC", pdc_in, NULL);
309
310	if (ACPI_FAILURE(status))
311		ACPI_DEBUG_PRINT((ACPI_DB_INFO,
312		    "Could not evaluate _PDC, using legacy perf. control.\n"));
313
314	return status;
315}
316
317void acpi_processor_set_pdc(acpi_handle handle)
318{
319	struct acpi_object_list *obj_list;
320
321	if (arch_has_acpi_pdc() == false)
322		return;
323
324	obj_list = acpi_processor_alloc_pdc();
325	if (!obj_list)
326		return;
327
328	acpi_processor_eval_pdc(handle, obj_list);
329
330	kfree(obj_list->pointer->buffer.pointer);
331	kfree(obj_list->pointer);
332	kfree(obj_list);
333}
334EXPORT_SYMBOL_GPL(acpi_processor_set_pdc);
335
336static acpi_status
337early_init_pdc(acpi_handle handle, u32 lvl, void *context, void **rv)
338{
339	if (processor_physically_present(handle) == false)
340		return AE_OK;
341
342	acpi_processor_set_pdc(handle);
343	return AE_OK;
344}
345
346void __init acpi_early_processor_set_pdc(void)
347{
348
349#ifdef CONFIG_SMP
350	if (ACPI_FAILURE(acpi_get_table(ACPI_SIG_MADT, 0,
351				(struct acpi_table_header **)&madt)))
352		madt = NULL;
353#endif
354
355	/*
356	 * Check whether the system is DMI table. If yes, OSPM
357	 * should not use mwait for CPU-states.
358	 */
359	dmi_check_system(processor_idle_dmi_table);
360
361	acpi_walk_namespace(ACPI_TYPE_PROCESSOR, ACPI_ROOT_OBJECT,
362			    ACPI_UINT32_MAX,
363			    early_init_pdc, NULL, NULL, NULL);
364}
365