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