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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 (!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 */