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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#include <linux/slab.h>
12
13#include <acpi/acpi_drivers.h>
14#include <acpi/processor.h>
15
16#include "internal.h"
17
18#define PREFIX "ACPI: "
19#define _COMPONENT ACPI_PROCESSOR_COMPONENT
20ACPI_MODULE_NAME("processor_core");
21
22static int __init set_no_mwait(const struct dmi_system_id *id)
23{
24 printk(KERN_NOTICE PREFIX "%s detected - "
25 "disabling mwait for CPU C-states\n", id->ident);
26 boot_option_idle_override = IDLE_NOMWAIT;
27 return 0;
28}
29
30static struct dmi_system_id __initdata processor_idle_dmi_table[] = {
31 {
32 set_no_mwait, "Extensa 5220", {
33 DMI_MATCH(DMI_BIOS_VENDOR, "Phoenix Technologies LTD"),
34 DMI_MATCH(DMI_SYS_VENDOR, "Acer"),
35 DMI_MATCH(DMI_PRODUCT_VERSION, "0100"),
36 DMI_MATCH(DMI_BOARD_NAME, "Columbia") }, NULL},
37 {},
38};
39
40static int map_lapic_id(struct acpi_subtable_header *entry,
41 u32 acpi_id, int *apic_id)
42{
43 struct acpi_madt_local_apic *lapic =
44 (struct acpi_madt_local_apic *)entry;
45
46 if (!(lapic->lapic_flags & ACPI_MADT_ENABLED))
47 return 0;
48
49 if (lapic->processor_id != acpi_id)
50 return 0;
51
52 *apic_id = lapic->id;
53 return 1;
54}
55
56static int map_x2apic_id(struct acpi_subtable_header *entry,
57 int device_declaration, u32 acpi_id, int *apic_id)
58{
59 struct acpi_madt_local_x2apic *apic =
60 (struct acpi_madt_local_x2apic *)entry;
61
62 if (!(apic->lapic_flags & ACPI_MADT_ENABLED))
63 return 0;
64
65 if (device_declaration && (apic->uid == acpi_id)) {
66 *apic_id = apic->local_apic_id;
67 return 1;
68 }
69
70 return 0;
71}
72
73static int map_lsapic_id(struct acpi_subtable_header *entry,
74 int device_declaration, u32 acpi_id, int *apic_id)
75{
76 struct acpi_madt_local_sapic *lsapic =
77 (struct acpi_madt_local_sapic *)entry;
78
79 if (!(lsapic->lapic_flags & ACPI_MADT_ENABLED))
80 return 0;
81
82 if (device_declaration) {
83 if ((entry->length < 16) || (lsapic->uid != acpi_id))
84 return 0;
85 } else if (lsapic->processor_id != acpi_id)
86 return 0;
87
88 *apic_id = (lsapic->id << 8) | lsapic->eid;
89 return 1;
90}
91
92static int map_madt_entry(int type, u32 acpi_id)
93{
94 unsigned long madt_end, entry;
95 static struct acpi_table_madt *madt;
96 static int read_madt;
97 int apic_id = -1;
98
99 if (!read_madt) {
100 if (ACPI_FAILURE(acpi_get_table(ACPI_SIG_MADT, 0,
101 (struct acpi_table_header **)&madt)))
102 madt = NULL;
103 read_madt++;
104 }
105
106 if (!madt)
107 return apic_id;
108
109 entry = (unsigned long)madt;
110 madt_end = entry + madt->header.length;
111
112 /* Parse all entries looking for a match. */
113
114 entry += sizeof(struct acpi_table_madt);
115 while (entry + sizeof(struct acpi_subtable_header) < madt_end) {
116 struct acpi_subtable_header *header =
117 (struct acpi_subtable_header *)entry;
118 if (header->type == ACPI_MADT_TYPE_LOCAL_APIC) {
119 if (map_lapic_id(header, acpi_id, &apic_id))
120 break;
121 } else if (header->type == ACPI_MADT_TYPE_LOCAL_X2APIC) {
122 if (map_x2apic_id(header, type, acpi_id, &apic_id))
123 break;
124 } else if (header->type == ACPI_MADT_TYPE_LOCAL_SAPIC) {
125 if (map_lsapic_id(header, type, acpi_id, &apic_id))
126 break;
127 }
128 entry += header->length;
129 }
130 return apic_id;
131}
132
133static int map_mat_entry(acpi_handle handle, int type, u32 acpi_id)
134{
135 struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
136 union acpi_object *obj;
137 struct acpi_subtable_header *header;
138 int apic_id = -1;
139
140 if (ACPI_FAILURE(acpi_evaluate_object(handle, "_MAT", NULL, &buffer)))
141 goto exit;
142
143 if (!buffer.length || !buffer.pointer)
144 goto exit;
145
146 obj = buffer.pointer;
147 if (obj->type != ACPI_TYPE_BUFFER ||
148 obj->buffer.length < sizeof(struct acpi_subtable_header)) {
149 goto exit;
150 }
151
152 header = (struct acpi_subtable_header *)obj->buffer.pointer;
153 if (header->type == ACPI_MADT_TYPE_LOCAL_APIC) {
154 map_lapic_id(header, acpi_id, &apic_id);
155 } else if (header->type == ACPI_MADT_TYPE_LOCAL_SAPIC) {
156 map_lsapic_id(header, type, acpi_id, &apic_id);
157 }
158
159exit:
160 if (buffer.pointer)
161 kfree(buffer.pointer);
162 return apic_id;
163}
164
165int acpi_get_cpuid(acpi_handle handle, int type, u32 acpi_id)
166{
167#ifdef CONFIG_SMP
168 int i;
169#endif
170 int apic_id = -1;
171
172 apic_id = map_mat_entry(handle, type, acpi_id);
173 if (apic_id == -1)
174 apic_id = map_madt_entry(type, acpi_id);
175 if (apic_id == -1)
176 return apic_id;
177
178#ifdef CONFIG_SMP
179 for_each_possible_cpu(i) {
180 if (cpu_physical_id(i) == apic_id)
181 return i;
182 }
183#else
184 /* In UP kernel, only processor 0 is valid */
185 if (apic_id == 0)
186 return apic_id;
187#endif
188 return -1;
189}
190EXPORT_SYMBOL_GPL(acpi_get_cpuid);
191
192static bool __init processor_physically_present(acpi_handle handle)
193{
194 int cpuid, type;
195 u32 acpi_id;
196 acpi_status status;
197 acpi_object_type acpi_type;
198 unsigned long long tmp;
199 union acpi_object object = { 0 };
200 struct acpi_buffer buffer = { sizeof(union acpi_object), &object };
201
202 status = acpi_get_type(handle, &acpi_type);
203 if (ACPI_FAILURE(status))
204 return false;
205
206 switch (acpi_type) {
207 case ACPI_TYPE_PROCESSOR:
208 status = acpi_evaluate_object(handle, NULL, NULL, &buffer);
209 if (ACPI_FAILURE(status))
210 return false;
211 acpi_id = object.processor.proc_id;
212 break;
213 case ACPI_TYPE_DEVICE:
214 status = acpi_evaluate_integer(handle, "_UID", NULL, &tmp);
215 if (ACPI_FAILURE(status))
216 return false;
217 acpi_id = tmp;
218 break;
219 default:
220 return false;
221 }
222
223 type = (acpi_type == ACPI_TYPE_DEVICE) ? 1 : 0;
224 cpuid = acpi_get_cpuid(handle, type, acpi_id);
225
226 if (cpuid == -1)
227 return false;
228
229 return true;
230}
231
232static void __cpuinit acpi_set_pdc_bits(u32 *buf)
233{
234 buf[0] = ACPI_PDC_REVISION_ID;
235 buf[1] = 1;
236
237 /* Enable coordination with firmware's _TSD info */
238 buf[2] = ACPI_PDC_SMP_T_SWCOORD;
239
240 /* Twiddle arch-specific bits needed for _PDC */
241 arch_acpi_set_pdc_bits(buf);
242}
243
244static struct acpi_object_list *__cpuinit acpi_processor_alloc_pdc(void)
245{
246 struct acpi_object_list *obj_list;
247 union acpi_object *obj;
248 u32 *buf;
249
250 /* allocate and initialize pdc. It will be used later. */
251 obj_list = kmalloc(sizeof(struct acpi_object_list), GFP_KERNEL);
252 if (!obj_list) {
253 printk(KERN_ERR "Memory allocation error\n");
254 return NULL;
255 }
256
257 obj = kmalloc(sizeof(union acpi_object), GFP_KERNEL);
258 if (!obj) {
259 printk(KERN_ERR "Memory allocation error\n");
260 kfree(obj_list);
261 return NULL;
262 }
263
264 buf = kmalloc(12, GFP_KERNEL);
265 if (!buf) {
266 printk(KERN_ERR "Memory allocation error\n");
267 kfree(obj);
268 kfree(obj_list);
269 return NULL;
270 }
271
272 acpi_set_pdc_bits(buf);
273
274 obj->type = ACPI_TYPE_BUFFER;
275 obj->buffer.length = 12;
276 obj->buffer.pointer = (u8 *) buf;
277 obj_list->count = 1;
278 obj_list->pointer = obj;
279
280 return obj_list;
281}
282
283/*
284 * _PDC is required for a BIOS-OS handshake for most of the newer
285 * ACPI processor features.
286 */
287static int __cpuinit
288acpi_processor_eval_pdc(acpi_handle handle, struct acpi_object_list *pdc_in)
289{
290 acpi_status status = AE_OK;
291
292 if (boot_option_idle_override == IDLE_NOMWAIT) {
293 /*
294 * If mwait is disabled for CPU C-states, the C2C3_FFH access
295 * mode will be disabled in the parameter of _PDC object.
296 * Of course C1_FFH access mode will also be disabled.
297 */
298 union acpi_object *obj;
299 u32 *buffer = NULL;
300
301 obj = pdc_in->pointer;
302 buffer = (u32 *)(obj->buffer.pointer);
303 buffer[2] &= ~(ACPI_PDC_C_C2C3_FFH | ACPI_PDC_C_C1_FFH);
304
305 }
306 status = acpi_evaluate_object(handle, "_PDC", pdc_in, NULL);
307
308 if (ACPI_FAILURE(status))
309 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
310 "Could not evaluate _PDC, using legacy perf. control.\n"));
311
312 return status;
313}
314
315void __cpuinit acpi_processor_set_pdc(acpi_handle handle)
316{
317 struct acpi_object_list *obj_list;
318
319 if (arch_has_acpi_pdc() == false)
320 return;
321
322 obj_list = acpi_processor_alloc_pdc();
323 if (!obj_list)
324 return;
325
326 acpi_processor_eval_pdc(handle, obj_list);
327
328 kfree(obj_list->pointer->buffer.pointer);
329 kfree(obj_list->pointer);
330 kfree(obj_list);
331}
332
333static acpi_status __init
334early_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
343void __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 acpi_get_devices("ACPI0007", early_init_pdc, NULL, NULL);
355}
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 *
8 * I/O APIC hotplug support
9 * Yinghai Lu <yinghai@kernel.org>
10 * Jiang Liu <jiang.liu@intel.com>
11 */
12#include <linux/export.h>
13#include <linux/acpi.h>
14#include <acpi/processor.h>
15
16#define _COMPONENT ACPI_PROCESSOR_COMPONENT
17ACPI_MODULE_NAME("processor_core");
18
19static struct acpi_table_madt *get_madt_table(void)
20{
21 static struct acpi_table_madt *madt;
22 static int read_madt;
23
24 if (!read_madt) {
25 if (ACPI_FAILURE(acpi_get_table(ACPI_SIG_MADT, 0,
26 (struct acpi_table_header **)&madt)))
27 madt = NULL;
28 read_madt++;
29 }
30
31 return madt;
32}
33
34static int map_lapic_id(struct acpi_subtable_header *entry,
35 u32 acpi_id, phys_cpuid_t *apic_id, bool ignore_disabled)
36{
37 struct acpi_madt_local_apic *lapic =
38 container_of(entry, struct acpi_madt_local_apic, header);
39
40 if (ignore_disabled && !(lapic->lapic_flags & ACPI_MADT_ENABLED))
41 return -ENODEV;
42
43 if (lapic->processor_id != acpi_id)
44 return -EINVAL;
45
46 *apic_id = lapic->id;
47 return 0;
48}
49
50static int map_x2apic_id(struct acpi_subtable_header *entry,
51 int device_declaration, u32 acpi_id, phys_cpuid_t *apic_id,
52 bool ignore_disabled)
53{
54 struct acpi_madt_local_x2apic *apic =
55 container_of(entry, struct acpi_madt_local_x2apic, header);
56
57 if (ignore_disabled && !(apic->lapic_flags & ACPI_MADT_ENABLED))
58 return -ENODEV;
59
60 if (device_declaration && (apic->uid == acpi_id)) {
61 *apic_id = apic->local_apic_id;
62 return 0;
63 }
64
65 return -EINVAL;
66}
67
68static int map_lsapic_id(struct acpi_subtable_header *entry,
69 int device_declaration, u32 acpi_id, phys_cpuid_t *apic_id,
70 bool ignore_disabled)
71{
72 struct acpi_madt_local_sapic *lsapic =
73 container_of(entry, struct acpi_madt_local_sapic, header);
74
75 if (ignore_disabled && !(lsapic->lapic_flags & ACPI_MADT_ENABLED))
76 return -ENODEV;
77
78 if (device_declaration) {
79 if ((entry->length < 16) || (lsapic->uid != acpi_id))
80 return -EINVAL;
81 } else if (lsapic->processor_id != acpi_id)
82 return -EINVAL;
83
84 *apic_id = (lsapic->id << 8) | lsapic->eid;
85 return 0;
86}
87
88/*
89 * Retrieve the ARM CPU physical identifier (MPIDR)
90 */
91static int map_gicc_mpidr(struct acpi_subtable_header *entry,
92 int device_declaration, u32 acpi_id, phys_cpuid_t *mpidr,
93 bool ignore_disabled)
94{
95 struct acpi_madt_generic_interrupt *gicc =
96 container_of(entry, struct acpi_madt_generic_interrupt, header);
97
98 if (ignore_disabled && !(gicc->flags & ACPI_MADT_ENABLED))
99 return -ENODEV;
100
101 /* device_declaration means Device object in DSDT, in the
102 * GIC interrupt model, logical processors are required to
103 * have a Processor Device object in the DSDT, so we should
104 * check device_declaration here
105 */
106 if (device_declaration && (gicc->uid == acpi_id)) {
107 *mpidr = gicc->arm_mpidr;
108 return 0;
109 }
110
111 return -EINVAL;
112}
113
114static phys_cpuid_t map_madt_entry(struct acpi_table_madt *madt,
115 int type, u32 acpi_id, bool ignore_disabled)
116{
117 unsigned long madt_end, entry;
118 phys_cpuid_t phys_id = PHYS_CPUID_INVALID; /* CPU hardware ID */
119
120 if (!madt)
121 return phys_id;
122
123 entry = (unsigned long)madt;
124 madt_end = entry + madt->header.length;
125
126 /* Parse all entries looking for a match. */
127
128 entry += sizeof(struct acpi_table_madt);
129 while (entry + sizeof(struct acpi_subtable_header) < madt_end) {
130 struct acpi_subtable_header *header =
131 (struct acpi_subtable_header *)entry;
132 if (header->type == ACPI_MADT_TYPE_LOCAL_APIC) {
133 if (!map_lapic_id(header, acpi_id, &phys_id,
134 ignore_disabled))
135 break;
136 } else if (header->type == ACPI_MADT_TYPE_LOCAL_X2APIC) {
137 if (!map_x2apic_id(header, type, acpi_id, &phys_id,
138 ignore_disabled))
139 break;
140 } else if (header->type == ACPI_MADT_TYPE_LOCAL_SAPIC) {
141 if (!map_lsapic_id(header, type, acpi_id, &phys_id,
142 ignore_disabled))
143 break;
144 } else if (header->type == ACPI_MADT_TYPE_GENERIC_INTERRUPT) {
145 if (!map_gicc_mpidr(header, type, acpi_id, &phys_id,
146 ignore_disabled))
147 break;
148 }
149 entry += header->length;
150 }
151 return phys_id;
152}
153
154phys_cpuid_t __init acpi_map_madt_entry(u32 acpi_id)
155{
156 struct acpi_table_madt *madt = NULL;
157 phys_cpuid_t rv;
158
159 acpi_get_table(ACPI_SIG_MADT, 0,
160 (struct acpi_table_header **)&madt);
161 if (!madt)
162 return PHYS_CPUID_INVALID;
163
164 rv = map_madt_entry(madt, 1, acpi_id, true);
165
166 acpi_put_table((struct acpi_table_header *)madt);
167
168 return rv;
169}
170
171static phys_cpuid_t map_mat_entry(acpi_handle handle, int type, u32 acpi_id,
172 bool ignore_disabled)
173{
174 struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
175 union acpi_object *obj;
176 struct acpi_subtable_header *header;
177 phys_cpuid_t phys_id = PHYS_CPUID_INVALID;
178
179 if (ACPI_FAILURE(acpi_evaluate_object(handle, "_MAT", NULL, &buffer)))
180 goto exit;
181
182 if (!buffer.length || !buffer.pointer)
183 goto exit;
184
185 obj = buffer.pointer;
186 if (obj->type != ACPI_TYPE_BUFFER ||
187 obj->buffer.length < sizeof(struct acpi_subtable_header)) {
188 goto exit;
189 }
190
191 header = (struct acpi_subtable_header *)obj->buffer.pointer;
192 if (header->type == ACPI_MADT_TYPE_LOCAL_APIC)
193 map_lapic_id(header, acpi_id, &phys_id, ignore_disabled);
194 else if (header->type == ACPI_MADT_TYPE_LOCAL_SAPIC)
195 map_lsapic_id(header, type, acpi_id, &phys_id, ignore_disabled);
196 else if (header->type == ACPI_MADT_TYPE_LOCAL_X2APIC)
197 map_x2apic_id(header, type, acpi_id, &phys_id, ignore_disabled);
198 else if (header->type == ACPI_MADT_TYPE_GENERIC_INTERRUPT)
199 map_gicc_mpidr(header, type, acpi_id, &phys_id,
200 ignore_disabled);
201
202exit:
203 kfree(buffer.pointer);
204 return phys_id;
205}
206
207static phys_cpuid_t __acpi_get_phys_id(acpi_handle handle, int type,
208 u32 acpi_id, bool ignore_disabled)
209{
210 phys_cpuid_t phys_id;
211
212 phys_id = map_mat_entry(handle, type, acpi_id, ignore_disabled);
213 if (invalid_phys_cpuid(phys_id))
214 phys_id = map_madt_entry(get_madt_table(), type, acpi_id,
215 ignore_disabled);
216
217 return phys_id;
218}
219
220phys_cpuid_t acpi_get_phys_id(acpi_handle handle, int type, u32 acpi_id)
221{
222 return __acpi_get_phys_id(handle, type, acpi_id, true);
223}
224
225int acpi_map_cpuid(phys_cpuid_t phys_id, u32 acpi_id)
226{
227#ifdef CONFIG_SMP
228 int i;
229#endif
230
231 if (invalid_phys_cpuid(phys_id)) {
232 /*
233 * On UP processor, there is no _MAT or MADT table.
234 * So above phys_id is always set to PHYS_CPUID_INVALID.
235 *
236 * BIOS may define multiple CPU handles even for UP processor.
237 * For example,
238 *
239 * Scope (_PR)
240 * {
241 * Processor (CPU0, 0x00, 0x00000410, 0x06) {}
242 * Processor (CPU1, 0x01, 0x00000410, 0x06) {}
243 * Processor (CPU2, 0x02, 0x00000410, 0x06) {}
244 * Processor (CPU3, 0x03, 0x00000410, 0x06) {}
245 * }
246 *
247 * Ignores phys_id and always returns 0 for the processor
248 * handle with acpi id 0 if nr_cpu_ids is 1.
249 * This should be the case if SMP tables are not found.
250 * Return -EINVAL for other CPU's handle.
251 */
252 if (nr_cpu_ids <= 1 && acpi_id == 0)
253 return acpi_id;
254 else
255 return -EINVAL;
256 }
257
258#ifdef CONFIG_SMP
259 for_each_possible_cpu(i) {
260 if (cpu_physical_id(i) == phys_id)
261 return i;
262 }
263#else
264 /* In UP kernel, only processor 0 is valid */
265 if (phys_id == 0)
266 return phys_id;
267#endif
268 return -ENODEV;
269}
270
271int acpi_get_cpuid(acpi_handle handle, int type, u32 acpi_id)
272{
273 phys_cpuid_t phys_id;
274
275 phys_id = acpi_get_phys_id(handle, type, acpi_id);
276
277 return acpi_map_cpuid(phys_id, acpi_id);
278}
279EXPORT_SYMBOL_GPL(acpi_get_cpuid);
280
281#ifdef CONFIG_ACPI_HOTPLUG_CPU
282static bool __init
283map_processor(acpi_handle handle, phys_cpuid_t *phys_id, int *cpuid)
284{
285 int type, id;
286 u32 acpi_id;
287 acpi_status status;
288 acpi_object_type acpi_type;
289 unsigned long long tmp;
290 union acpi_object object = { 0 };
291 struct acpi_buffer buffer = { sizeof(union acpi_object), &object };
292
293 status = acpi_get_type(handle, &acpi_type);
294 if (ACPI_FAILURE(status))
295 return false;
296
297 switch (acpi_type) {
298 case ACPI_TYPE_PROCESSOR:
299 status = acpi_evaluate_object(handle, NULL, NULL, &buffer);
300 if (ACPI_FAILURE(status))
301 return false;
302 acpi_id = object.processor.proc_id;
303
304 /* validate the acpi_id */
305 if(acpi_processor_validate_proc_id(acpi_id))
306 return false;
307 break;
308 case ACPI_TYPE_DEVICE:
309 status = acpi_evaluate_integer(handle, "_UID", NULL, &tmp);
310 if (ACPI_FAILURE(status))
311 return false;
312 acpi_id = tmp;
313 break;
314 default:
315 return false;
316 }
317
318 type = (acpi_type == ACPI_TYPE_DEVICE) ? 1 : 0;
319
320 *phys_id = __acpi_get_phys_id(handle, type, acpi_id, false);
321 id = acpi_map_cpuid(*phys_id, acpi_id);
322
323 if (id < 0)
324 return false;
325 *cpuid = id;
326 return true;
327}
328
329static acpi_status __init
330set_processor_node_mapping(acpi_handle handle, u32 lvl, void *context,
331 void **rv)
332{
333 phys_cpuid_t phys_id;
334 int cpu_id;
335
336 if (!map_processor(handle, &phys_id, &cpu_id))
337 return AE_ERROR;
338
339 acpi_map_cpu2node(handle, cpu_id, phys_id);
340 return AE_OK;
341}
342
343void __init acpi_set_processor_mapping(void)
344{
345 /* Set persistent cpu <-> node mapping for all processors. */
346 acpi_walk_namespace(ACPI_TYPE_PROCESSOR, ACPI_ROOT_OBJECT,
347 ACPI_UINT32_MAX, set_processor_node_mapping,
348 NULL, NULL, NULL);
349}
350#else
351void __init acpi_set_processor_mapping(void) {}
352#endif /* CONFIG_ACPI_HOTPLUG_CPU */
353
354#ifdef CONFIG_ACPI_HOTPLUG_IOAPIC
355static int get_ioapic_id(struct acpi_subtable_header *entry, u32 gsi_base,
356 u64 *phys_addr, int *ioapic_id)
357{
358 struct acpi_madt_io_apic *ioapic = (struct acpi_madt_io_apic *)entry;
359
360 if (ioapic->global_irq_base != gsi_base)
361 return 0;
362
363 *phys_addr = ioapic->address;
364 *ioapic_id = ioapic->id;
365 return 1;
366}
367
368static int parse_madt_ioapic_entry(u32 gsi_base, u64 *phys_addr)
369{
370 struct acpi_subtable_header *hdr;
371 unsigned long madt_end, entry;
372 struct acpi_table_madt *madt;
373 int apic_id = -1;
374
375 madt = get_madt_table();
376 if (!madt)
377 return apic_id;
378
379 entry = (unsigned long)madt;
380 madt_end = entry + madt->header.length;
381
382 /* Parse all entries looking for a match. */
383 entry += sizeof(struct acpi_table_madt);
384 while (entry + sizeof(struct acpi_subtable_header) < madt_end) {
385 hdr = (struct acpi_subtable_header *)entry;
386 if (hdr->type == ACPI_MADT_TYPE_IO_APIC &&
387 get_ioapic_id(hdr, gsi_base, phys_addr, &apic_id))
388 break;
389 else
390 entry += hdr->length;
391 }
392
393 return apic_id;
394}
395
396static int parse_mat_ioapic_entry(acpi_handle handle, u32 gsi_base,
397 u64 *phys_addr)
398{
399 struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
400 struct acpi_subtable_header *header;
401 union acpi_object *obj;
402 int apic_id = -1;
403
404 if (ACPI_FAILURE(acpi_evaluate_object(handle, "_MAT", NULL, &buffer)))
405 goto exit;
406
407 if (!buffer.length || !buffer.pointer)
408 goto exit;
409
410 obj = buffer.pointer;
411 if (obj->type != ACPI_TYPE_BUFFER ||
412 obj->buffer.length < sizeof(struct acpi_subtable_header))
413 goto exit;
414
415 header = (struct acpi_subtable_header *)obj->buffer.pointer;
416 if (header->type == ACPI_MADT_TYPE_IO_APIC)
417 get_ioapic_id(header, gsi_base, phys_addr, &apic_id);
418
419exit:
420 kfree(buffer.pointer);
421 return apic_id;
422}
423
424/**
425 * acpi_get_ioapic_id - Get IOAPIC ID and physical address matching @gsi_base
426 * @handle: ACPI object for IOAPIC device
427 * @gsi_base: GSI base to match with
428 * @phys_addr: Pointer to store physical address of matching IOAPIC record
429 *
430 * Walk resources returned by ACPI_MAT method, then ACPI MADT table, to search
431 * for an ACPI IOAPIC record matching @gsi_base.
432 * Return IOAPIC id and store physical address in @phys_addr if found a match,
433 * otherwise return <0.
434 */
435int acpi_get_ioapic_id(acpi_handle handle, u32 gsi_base, u64 *phys_addr)
436{
437 int apic_id;
438
439 apic_id = parse_mat_ioapic_entry(handle, gsi_base, phys_addr);
440 if (apic_id == -1)
441 apic_id = parse_madt_ioapic_entry(gsi_base, phys_addr);
442
443 return apic_id;
444}
445#endif /* CONFIG_ACPI_HOTPLUG_IOAPIC */