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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// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * Copyright (C) 2005 Intel Corporation
4 * Copyright (C) 2009 Hewlett-Packard Development Company, L.P.
5 *
6 * Alex Chiang <achiang@hp.com>
7 * - Unified x86/ia64 implementations
8 *
9 * I/O APIC hotplug support
10 * Yinghai Lu <yinghai@kernel.org>
11 * Jiang Liu <jiang.liu@intel.com>
12 */
13#include <linux/export.h>
14#include <linux/acpi.h>
15#include <acpi/processor.h>
16
17static struct acpi_table_madt *get_madt_table(void)
18{
19 static struct acpi_table_madt *madt;
20 static int read_madt;
21
22 if (!read_madt) {
23 if (ACPI_FAILURE(acpi_get_table(ACPI_SIG_MADT, 0,
24 (struct acpi_table_header **)&madt)))
25 madt = NULL;
26 read_madt++;
27 }
28
29 return madt;
30}
31
32static int map_lapic_id(struct acpi_subtable_header *entry,
33 u32 acpi_id, phys_cpuid_t *apic_id)
34{
35 struct acpi_madt_local_apic *lapic =
36 container_of(entry, struct acpi_madt_local_apic, header);
37
38 if (!(lapic->lapic_flags & ACPI_MADT_ENABLED))
39 return -ENODEV;
40
41 if (lapic->processor_id != acpi_id)
42 return -EINVAL;
43
44 *apic_id = lapic->id;
45 return 0;
46}
47
48static int map_x2apic_id(struct acpi_subtable_header *entry,
49 int device_declaration, u32 acpi_id, phys_cpuid_t *apic_id)
50{
51 struct acpi_madt_local_x2apic *apic =
52 container_of(entry, struct acpi_madt_local_x2apic, header);
53
54 if (!(apic->lapic_flags & ACPI_MADT_ENABLED))
55 return -ENODEV;
56
57 if (device_declaration && (apic->uid == acpi_id)) {
58 *apic_id = apic->local_apic_id;
59 return 0;
60 }
61
62 return -EINVAL;
63}
64
65static int map_lsapic_id(struct acpi_subtable_header *entry,
66 int device_declaration, u32 acpi_id, phys_cpuid_t *apic_id)
67{
68 struct acpi_madt_local_sapic *lsapic =
69 container_of(entry, struct acpi_madt_local_sapic, header);
70
71 if (!(lsapic->lapic_flags & ACPI_MADT_ENABLED))
72 return -ENODEV;
73
74 if (device_declaration) {
75 if ((entry->length < 16) || (lsapic->uid != acpi_id))
76 return -EINVAL;
77 } else if (lsapic->processor_id != acpi_id)
78 return -EINVAL;
79
80 *apic_id = (lsapic->id << 8) | lsapic->eid;
81 return 0;
82}
83
84/*
85 * Retrieve the ARM CPU physical identifier (MPIDR)
86 */
87static int map_gicc_mpidr(struct acpi_subtable_header *entry,
88 int device_declaration, u32 acpi_id, phys_cpuid_t *mpidr)
89{
90 struct acpi_madt_generic_interrupt *gicc =
91 container_of(entry, struct acpi_madt_generic_interrupt, header);
92
93 if (!(gicc->flags &
94 (ACPI_MADT_ENABLED | ACPI_MADT_GICC_ONLINE_CAPABLE)))
95 return -ENODEV;
96
97 /* device_declaration means Device object in DSDT, in the
98 * GIC interrupt model, logical processors are required to
99 * have a Processor Device object in the DSDT, so we should
100 * check device_declaration here
101 */
102 if (device_declaration && (gicc->uid == acpi_id)) {
103 *mpidr = gicc->arm_mpidr;
104 return 0;
105 }
106
107 return -EINVAL;
108}
109
110/*
111 * Retrieve the RISC-V hartid for the processor
112 */
113static int map_rintc_hartid(struct acpi_subtable_header *entry,
114 int device_declaration, u32 acpi_id,
115 phys_cpuid_t *hartid)
116{
117 struct acpi_madt_rintc *rintc =
118 container_of(entry, struct acpi_madt_rintc, header);
119
120 if (!(rintc->flags & ACPI_MADT_ENABLED))
121 return -ENODEV;
122
123 /* device_declaration means Device object in DSDT, in the
124 * RISC-V, logical processors are required to
125 * have a Processor Device object in the DSDT, so we should
126 * check device_declaration here
127 */
128 if (device_declaration && rintc->uid == acpi_id) {
129 *hartid = rintc->hart_id;
130 return 0;
131 }
132
133 return -EINVAL;
134}
135
136/*
137 * Retrieve LoongArch CPU physical id
138 */
139static int map_core_pic_id(struct acpi_subtable_header *entry,
140 int device_declaration, u32 acpi_id, phys_cpuid_t *phys_id)
141{
142 struct acpi_madt_core_pic *core_pic =
143 container_of(entry, struct acpi_madt_core_pic, header);
144
145 if (!(core_pic->flags & ACPI_MADT_ENABLED))
146 return -ENODEV;
147
148 /* device_declaration means Device object in DSDT, in LoongArch
149 * system, logical processor acpi_id is required in _UID property
150 * of DSDT table, so we should check device_declaration here
151 */
152 if (device_declaration && (core_pic->processor_id == acpi_id)) {
153 *phys_id = core_pic->core_id;
154 return 0;
155 }
156
157 return -EINVAL;
158}
159
160static phys_cpuid_t map_madt_entry(struct acpi_table_madt *madt,
161 int type, u32 acpi_id)
162{
163 unsigned long madt_end, entry;
164 phys_cpuid_t phys_id = PHYS_CPUID_INVALID; /* CPU hardware ID */
165
166 if (!madt)
167 return phys_id;
168
169 entry = (unsigned long)madt;
170 madt_end = entry + madt->header.length;
171
172 /* Parse all entries looking for a match. */
173
174 entry += sizeof(struct acpi_table_madt);
175 while (entry + sizeof(struct acpi_subtable_header) < madt_end) {
176 struct acpi_subtable_header *header =
177 (struct acpi_subtable_header *)entry;
178 if (header->type == ACPI_MADT_TYPE_LOCAL_APIC) {
179 if (!map_lapic_id(header, acpi_id, &phys_id))
180 break;
181 } else if (header->type == ACPI_MADT_TYPE_LOCAL_X2APIC) {
182 if (!map_x2apic_id(header, type, acpi_id, &phys_id))
183 break;
184 } else if (header->type == ACPI_MADT_TYPE_LOCAL_SAPIC) {
185 if (!map_lsapic_id(header, type, acpi_id, &phys_id))
186 break;
187 } else if (header->type == ACPI_MADT_TYPE_GENERIC_INTERRUPT) {
188 if (!map_gicc_mpidr(header, type, acpi_id, &phys_id))
189 break;
190 } else if (header->type == ACPI_MADT_TYPE_RINTC) {
191 if (!map_rintc_hartid(header, type, acpi_id, &phys_id))
192 break;
193 } else if (header->type == ACPI_MADT_TYPE_CORE_PIC) {
194 if (!map_core_pic_id(header, type, acpi_id, &phys_id))
195 break;
196 }
197 entry += header->length;
198 }
199 return phys_id;
200}
201
202phys_cpuid_t __init acpi_map_madt_entry(u32 acpi_id)
203{
204 struct acpi_table_madt *madt = NULL;
205 phys_cpuid_t rv;
206
207 acpi_get_table(ACPI_SIG_MADT, 0,
208 (struct acpi_table_header **)&madt);
209 if (!madt)
210 return PHYS_CPUID_INVALID;
211
212 rv = map_madt_entry(madt, 1, acpi_id);
213
214 acpi_put_table((struct acpi_table_header *)madt);
215
216 return rv;
217}
218
219int __init acpi_get_madt_revision(void)
220{
221 struct acpi_table_header *madt = NULL;
222 int revision;
223
224 if (ACPI_FAILURE(acpi_get_table(ACPI_SIG_MADT, 0, &madt)))
225 return -EINVAL;
226
227 revision = madt->revision;
228
229 acpi_put_table(madt);
230
231 return revision;
232}
233
234static phys_cpuid_t map_mat_entry(acpi_handle handle, int type, u32 acpi_id)
235{
236 struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
237 union acpi_object *obj;
238 struct acpi_subtable_header *header;
239 phys_cpuid_t phys_id = PHYS_CPUID_INVALID;
240
241 if (ACPI_FAILURE(acpi_evaluate_object(handle, "_MAT", NULL, &buffer)))
242 goto exit;
243
244 if (!buffer.length || !buffer.pointer)
245 goto exit;
246
247 obj = buffer.pointer;
248 if (obj->type != ACPI_TYPE_BUFFER ||
249 obj->buffer.length < sizeof(struct acpi_subtable_header)) {
250 goto exit;
251 }
252
253 header = (struct acpi_subtable_header *)obj->buffer.pointer;
254 if (header->type == ACPI_MADT_TYPE_LOCAL_APIC)
255 map_lapic_id(header, acpi_id, &phys_id);
256 else if (header->type == ACPI_MADT_TYPE_LOCAL_SAPIC)
257 map_lsapic_id(header, type, acpi_id, &phys_id);
258 else if (header->type == ACPI_MADT_TYPE_LOCAL_X2APIC)
259 map_x2apic_id(header, type, acpi_id, &phys_id);
260 else if (header->type == ACPI_MADT_TYPE_GENERIC_INTERRUPT)
261 map_gicc_mpidr(header, type, acpi_id, &phys_id);
262 else if (header->type == ACPI_MADT_TYPE_CORE_PIC)
263 map_core_pic_id(header, type, acpi_id, &phys_id);
264
265exit:
266 kfree(buffer.pointer);
267 return phys_id;
268}
269
270phys_cpuid_t acpi_get_phys_id(acpi_handle handle, int type, u32 acpi_id)
271{
272 phys_cpuid_t phys_id;
273
274 phys_id = map_mat_entry(handle, type, acpi_id);
275 if (invalid_phys_cpuid(phys_id))
276 phys_id = map_madt_entry(get_madt_table(), type, acpi_id);
277
278 return phys_id;
279}
280EXPORT_SYMBOL_GPL(acpi_get_phys_id);
281
282int acpi_map_cpuid(phys_cpuid_t phys_id, u32 acpi_id)
283{
284#ifdef CONFIG_SMP
285 int i;
286#endif
287
288 if (invalid_phys_cpuid(phys_id)) {
289 /*
290 * On UP processor, there is no _MAT or MADT table.
291 * So above phys_id is always set to PHYS_CPUID_INVALID.
292 *
293 * BIOS may define multiple CPU handles even for UP processor.
294 * For example,
295 *
296 * Scope (_PR)
297 * {
298 * Processor (CPU0, 0x00, 0x00000410, 0x06) {}
299 * Processor (CPU1, 0x01, 0x00000410, 0x06) {}
300 * Processor (CPU2, 0x02, 0x00000410, 0x06) {}
301 * Processor (CPU3, 0x03, 0x00000410, 0x06) {}
302 * }
303 *
304 * Ignores phys_id and always returns 0 for the processor
305 * handle with acpi id 0 if nr_cpu_ids is 1.
306 * This should be the case if SMP tables are not found.
307 * Return -EINVAL for other CPU's handle.
308 */
309 if (nr_cpu_ids <= 1 && acpi_id == 0)
310 return acpi_id;
311 else
312 return -EINVAL;
313 }
314
315#ifdef CONFIG_SMP
316 for_each_possible_cpu(i) {
317 if (cpu_physical_id(i) == phys_id)
318 return i;
319 }
320#else
321 /* In UP kernel, only processor 0 is valid */
322 if (phys_id == 0)
323 return phys_id;
324#endif
325 return -ENODEV;
326}
327
328int acpi_get_cpuid(acpi_handle handle, int type, u32 acpi_id)
329{
330 phys_cpuid_t phys_id;
331
332 phys_id = acpi_get_phys_id(handle, type, acpi_id);
333
334 return acpi_map_cpuid(phys_id, acpi_id);
335}
336EXPORT_SYMBOL_GPL(acpi_get_cpuid);
337
338#ifdef CONFIG_ACPI_HOTPLUG_IOAPIC
339static int get_ioapic_id(struct acpi_subtable_header *entry, u32 gsi_base,
340 u64 *phys_addr, int *ioapic_id)
341{
342 struct acpi_madt_io_apic *ioapic = (struct acpi_madt_io_apic *)entry;
343
344 if (ioapic->global_irq_base != gsi_base)
345 return 0;
346
347 *phys_addr = ioapic->address;
348 *ioapic_id = ioapic->id;
349 return 1;
350}
351
352static int parse_madt_ioapic_entry(u32 gsi_base, u64 *phys_addr)
353{
354 struct acpi_subtable_header *hdr;
355 unsigned long madt_end, entry;
356 struct acpi_table_madt *madt;
357 int apic_id = -1;
358
359 madt = get_madt_table();
360 if (!madt)
361 return apic_id;
362
363 entry = (unsigned long)madt;
364 madt_end = entry + madt->header.length;
365
366 /* Parse all entries looking for a match. */
367 entry += sizeof(struct acpi_table_madt);
368 while (entry + sizeof(struct acpi_subtable_header) < madt_end) {
369 hdr = (struct acpi_subtable_header *)entry;
370 if (hdr->type == ACPI_MADT_TYPE_IO_APIC &&
371 get_ioapic_id(hdr, gsi_base, phys_addr, &apic_id))
372 break;
373 else
374 entry += hdr->length;
375 }
376
377 return apic_id;
378}
379
380static int parse_mat_ioapic_entry(acpi_handle handle, u32 gsi_base,
381 u64 *phys_addr)
382{
383 struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
384 struct acpi_subtable_header *header;
385 union acpi_object *obj;
386 int apic_id = -1;
387
388 if (ACPI_FAILURE(acpi_evaluate_object(handle, "_MAT", NULL, &buffer)))
389 goto exit;
390
391 if (!buffer.length || !buffer.pointer)
392 goto exit;
393
394 obj = buffer.pointer;
395 if (obj->type != ACPI_TYPE_BUFFER ||
396 obj->buffer.length < sizeof(struct acpi_subtable_header))
397 goto exit;
398
399 header = (struct acpi_subtable_header *)obj->buffer.pointer;
400 if (header->type == ACPI_MADT_TYPE_IO_APIC)
401 get_ioapic_id(header, gsi_base, phys_addr, &apic_id);
402
403exit:
404 kfree(buffer.pointer);
405 return apic_id;
406}
407
408/**
409 * acpi_get_ioapic_id - Get IOAPIC ID and physical address matching @gsi_base
410 * @handle: ACPI object for IOAPIC device
411 * @gsi_base: GSI base to match with
412 * @phys_addr: Pointer to store physical address of matching IOAPIC record
413 *
414 * Walk resources returned by ACPI_MAT method, then ACPI MADT table, to search
415 * for an ACPI IOAPIC record matching @gsi_base.
416 * Return IOAPIC id and store physical address in @phys_addr if found a match,
417 * otherwise return <0.
418 */
419int acpi_get_ioapic_id(acpi_handle handle, u32 gsi_base, u64 *phys_addr)
420{
421 int apic_id;
422
423 apic_id = parse_mat_ioapic_entry(handle, gsi_base, phys_addr);
424 if (apic_id == -1)
425 apic_id = parse_madt_ioapic_entry(gsi_base, phys_addr);
426
427 return apic_id;
428}
429#endif /* CONFIG_ACPI_HOTPLUG_IOAPIC */