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