xref: /linux-6.15/drivers/acpi/processor_core.c (revision edc7616c) 
1 /*
2  * Copyright (C) 2005 Intel Corporation
3  * Copyright (C) 2009 Hewlett-Packard Development Company, L.P.
4  *
5  *	Alex Chiang <[email protected]>
6  *	- Unified x86/ia64 implementations
7  *	Venkatesh Pallipadi <[email protected]>
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 int map_lapic_id(struct acpi_subtable_header *entry,
47 		 u32 acpi_id, int *apic_id)
48 {
49 	struct acpi_madt_local_apic *lapic =
50 		(struct acpi_madt_local_apic *)entry;
51 
52 	if (!(lapic->lapic_flags & ACPI_MADT_ENABLED))
53 		return 0;
54 
55 	if (lapic->processor_id != acpi_id)
56 		return 0;
57 
58 	*apic_id = lapic->id;
59 	return 1;
60 }
61 
62 static int map_x2apic_id(struct acpi_subtable_header *entry,
63 			 int device_declaration, u32 acpi_id, int *apic_id)
64 {
65 	struct acpi_madt_local_x2apic *apic =
66 		(struct acpi_madt_local_x2apic *)entry;
67 
68 	if (!(apic->lapic_flags & ACPI_MADT_ENABLED))
69 		return 0;
70 
71 	if (device_declaration && (apic->uid == acpi_id)) {
72 		*apic_id = apic->local_apic_id;
73 		return 1;
74 	}
75 
76 	return 0;
77 }
78 
79 static int map_lsapic_id(struct acpi_subtable_header *entry,
80 		int device_declaration, u32 acpi_id, int *apic_id)
81 {
82 	struct acpi_madt_local_sapic *lsapic =
83 		(struct acpi_madt_local_sapic *)entry;
84 
85 	if (!(lsapic->lapic_flags & ACPI_MADT_ENABLED))
86 		return 0;
87 
88 	if (device_declaration) {
89 		if ((entry->length < 16) || (lsapic->uid != acpi_id))
90 			return 0;
91 	} else if (lsapic->processor_id != acpi_id)
92 		return 0;
93 
94 	*apic_id = (lsapic->id << 8) | lsapic->eid;
95 	return 1;
96 }
97 
98 static int map_madt_entry(int type, u32 acpi_id)
99 {
100 	unsigned long madt_end, entry;
101 	static struct acpi_table_madt *madt;
102 	static int read_madt;
103 	int apic_id = -1;
104 
105 	if (!read_madt) {
106 		if (ACPI_FAILURE(acpi_get_table(ACPI_SIG_MADT, 0,
107 					(struct acpi_table_header **)&madt)))
108 			madt = NULL;
109 		read_madt++;
110 	}
111 
112 	if (!madt)
113 		return apic_id;
114 
115 	entry = (unsigned long)madt;
116 	madt_end = entry + madt->header.length;
117 
118 	/* Parse all entries looking for a match. */
119 
120 	entry += sizeof(struct acpi_table_madt);
121 	while (entry + sizeof(struct acpi_subtable_header) < madt_end) {
122 		struct acpi_subtable_header *header =
123 			(struct acpi_subtable_header *)entry;
124 		if (header->type == ACPI_MADT_TYPE_LOCAL_APIC) {
125 			if (map_lapic_id(header, acpi_id, &apic_id))
126 				break;
127 		} else if (header->type == ACPI_MADT_TYPE_LOCAL_X2APIC) {
128 			if (map_x2apic_id(header, type, acpi_id, &apic_id))
129 				break;
130 		} else if (header->type == ACPI_MADT_TYPE_LOCAL_SAPIC) {
131 			if (map_lsapic_id(header, type, acpi_id, &apic_id))
132 				break;
133 		}
134 		entry += header->length;
135 	}
136 	return apic_id;
137 }
138 
139 static int map_mat_entry(acpi_handle handle, int type, u32 acpi_id)
140 {
141 	struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
142 	union acpi_object *obj;
143 	struct acpi_subtable_header *header;
144 	int apic_id = -1;
145 
146 	if (ACPI_FAILURE(acpi_evaluate_object(handle, "_MAT", NULL, &buffer)))
147 		goto exit;
148 
149 	if (!buffer.length || !buffer.pointer)
150 		goto exit;
151 
152 	obj = buffer.pointer;
153 	if (obj->type != ACPI_TYPE_BUFFER ||
154 	    obj->buffer.length < sizeof(struct acpi_subtable_header)) {
155 		goto exit;
156 	}
157 
158 	header = (struct acpi_subtable_header *)obj->buffer.pointer;
159 	if (header->type == ACPI_MADT_TYPE_LOCAL_APIC) {
160 		map_lapic_id(header, acpi_id, &apic_id);
161 	} else if (header->type == ACPI_MADT_TYPE_LOCAL_SAPIC) {
162 		map_lsapic_id(header, type, acpi_id, &apic_id);
163 	}
164 
165 exit:
166 	if (buffer.pointer)
167 		kfree(buffer.pointer);
168 	return apic_id;
169 }
170 
171 int acpi_get_cpuid(acpi_handle handle, int type, u32 acpi_id)
172 {
173 	int i;
174 	int apic_id = -1;
175 
176 	apic_id = map_mat_entry(handle, type, acpi_id);
177 	if (apic_id == -1)
178 		apic_id = map_madt_entry(type, acpi_id);
179 	if (apic_id == -1)
180 		return apic_id;
181 
182 	for_each_possible_cpu(i) {
183 		if (cpu_physical_id(i) == apic_id)
184 			return i;
185 	}
186 	return -1;
187 }
188 EXPORT_SYMBOL_GPL(acpi_get_cpuid);
189 #endif
190 
191 static bool processor_physically_present(acpi_handle handle)
192 {
193 	int cpuid, type;
194 	u32 acpi_id;
195 	acpi_status status;
196 	acpi_object_type acpi_type;
197 	unsigned long long tmp;
198 	union acpi_object object = { 0 };
199 	struct acpi_buffer buffer = { sizeof(union acpi_object), &object };
200 
201 	status = acpi_get_type(handle, &acpi_type);
202 	if (ACPI_FAILURE(status))
203 		return false;
204 
205 	switch (acpi_type) {
206 	case ACPI_TYPE_PROCESSOR:
207 		status = acpi_evaluate_object(handle, NULL, NULL, &buffer);
208 		if (ACPI_FAILURE(status))
209 			return false;
210 		acpi_id = object.processor.proc_id;
211 		break;
212 	case ACPI_TYPE_DEVICE:
213 		status = acpi_evaluate_integer(handle, "_UID", NULL, &tmp);
214 		if (ACPI_FAILURE(status))
215 			return false;
216 		acpi_id = tmp;
217 		break;
218 	default:
219 		return false;
220 	}
221 
222 	type = (acpi_type == ACPI_TYPE_DEVICE) ? 1 : 0;
223 	cpuid = acpi_get_cpuid(handle, type, acpi_id);
224 
225 	if (cpuid == -1)
226 		return false;
227 
228 	return true;
229 }
230 
231 static void acpi_set_pdc_bits(u32 *buf)
232 {
233 	buf[0] = ACPI_PDC_REVISION_ID;
234 	buf[1] = 1;
235 
236 	/* Enable coordination with firmware's _TSD info */
237 	buf[2] = ACPI_PDC_SMP_T_SWCOORD;
238 
239 	/* Twiddle arch-specific bits needed for _PDC */
240 	arch_acpi_set_pdc_bits(buf);
241 }
242 
243 static struct acpi_object_list *acpi_processor_alloc_pdc(void)
244 {
245 	struct acpi_object_list *obj_list;
246 	union acpi_object *obj;
247 	u32 *buf;
248 
249 	/* allocate and initialize pdc. It will be used later. */
250 	obj_list = kmalloc(sizeof(struct acpi_object_list), GFP_KERNEL);
251 	if (!obj_list) {
252 		printk(KERN_ERR "Memory allocation error\n");
253 		return NULL;
254 	}
255 
256 	obj = kmalloc(sizeof(union acpi_object), GFP_KERNEL);
257 	if (!obj) {
258 		printk(KERN_ERR "Memory allocation error\n");
259 		kfree(obj_list);
260 		return NULL;
261 	}
262 
263 	buf = kmalloc(12, GFP_KERNEL);
264 	if (!buf) {
265 		printk(KERN_ERR "Memory allocation error\n");
266 		kfree(obj);
267 		kfree(obj_list);
268 		return NULL;
269 	}
270 
271 	acpi_set_pdc_bits(buf);
272 
273 	obj->type = ACPI_TYPE_BUFFER;
274 	obj->buffer.length = 12;
275 	obj->buffer.pointer = (u8 *) buf;
276 	obj_list->count = 1;
277 	obj_list->pointer = obj;
278 
279 	return obj_list;
280 }
281 
282 /*
283  * _PDC is required for a BIOS-OS handshake for most of the newer
284  * ACPI processor features.
285  */
286 static int
287 acpi_processor_eval_pdc(acpi_handle handle, struct acpi_object_list *pdc_in)
288 {
289 	acpi_status status = AE_OK;
290 
291 	if (idle_nomwait) {
292 		/*
293 		 * If mwait is disabled for CPU C-states, the C2C3_FFH access
294 		 * mode will be disabled in the parameter of _PDC object.
295 		 * Of course C1_FFH access mode will also be disabled.
296 		 */
297 		union acpi_object *obj;
298 		u32 *buffer = NULL;
299 
300 		obj = pdc_in->pointer;
301 		buffer = (u32 *)(obj->buffer.pointer);
302 		buffer[2] &= ~(ACPI_PDC_C_C2C3_FFH | ACPI_PDC_C_C1_FFH);
303 
304 	}
305 	status = acpi_evaluate_object(handle, "_PDC", pdc_in, NULL);
306 
307 	if (ACPI_FAILURE(status))
308 		ACPI_DEBUG_PRINT((ACPI_DB_INFO,
309 		    "Could not evaluate _PDC, using legacy perf. control.\n"));
310 
311 	return status;
312 }
313 
314 void acpi_processor_set_pdc(acpi_handle handle)
315 {
316 	struct acpi_object_list *obj_list;
317 
318 	if (arch_has_acpi_pdc() == false)
319 		return;
320 
321 	obj_list = acpi_processor_alloc_pdc();
322 	if (!obj_list)
323 		return;
324 
325 	acpi_processor_eval_pdc(handle, obj_list);
326 
327 	kfree(obj_list->pointer->buffer.pointer);
328 	kfree(obj_list->pointer);
329 	kfree(obj_list);
330 }
331 EXPORT_SYMBOL_GPL(acpi_processor_set_pdc);
332 
333 static acpi_status
334 early_init_pdc(acpi_handle handle, u32 lvl, void *context, void **rv)
335 {
336 	if (processor_physically_present(handle) == false)
337 		return AE_OK;
338 
339 	acpi_processor_set_pdc(handle);
340 	return AE_OK;
341 }
342 
343 void __init acpi_early_processor_set_pdc(void)
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 }
355