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
get_madt_table(void)17 static 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
map_lapic_id(struct acpi_subtable_header * entry,u32 acpi_id,phys_cpuid_t * apic_id)32 static 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
map_x2apic_id(struct acpi_subtable_header * entry,int device_declaration,u32 acpi_id,phys_cpuid_t * apic_id)48 static 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
map_lsapic_id(struct acpi_subtable_header * entry,int device_declaration,u32 acpi_id,phys_cpuid_t * apic_id)65 static 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 */
map_gicc_mpidr(struct acpi_subtable_header * entry,int device_declaration,u32 acpi_id,phys_cpuid_t * mpidr)87 static 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 & ACPI_MADT_ENABLED))
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
map_madt_entry(struct acpi_table_madt * madt,int type,u32 acpi_id)109 static phys_cpuid_t map_madt_entry(struct acpi_table_madt *madt,
110 int type, u32 acpi_id)
111 {
112 unsigned long madt_end, entry;
113 phys_cpuid_t phys_id = PHYS_CPUID_INVALID; /* CPU hardware ID */
114
115 if (!madt)
116 return phys_id;
117
118 entry = (unsigned long)madt;
119 madt_end = entry + madt->header.length;
120
121 /* Parse all entries looking for a match. */
122
123 entry += sizeof(struct acpi_table_madt);
124 while (entry + sizeof(struct acpi_subtable_header) < madt_end) {
125 struct acpi_subtable_header *header =
126 (struct acpi_subtable_header *)entry;
127 if (header->type == ACPI_MADT_TYPE_LOCAL_APIC) {
128 if (!map_lapic_id(header, acpi_id, &phys_id))
129 break;
130 } else if (header->type == ACPI_MADT_TYPE_LOCAL_X2APIC) {
131 if (!map_x2apic_id(header, type, acpi_id, &phys_id))
132 break;
133 } else if (header->type == ACPI_MADT_TYPE_LOCAL_SAPIC) {
134 if (!map_lsapic_id(header, type, acpi_id, &phys_id))
135 break;
136 } else if (header->type == ACPI_MADT_TYPE_GENERIC_INTERRUPT) {
137 if (!map_gicc_mpidr(header, type, acpi_id, &phys_id))
138 break;
139 }
140 entry += header->length;
141 }
142 return phys_id;
143 }
144
acpi_map_madt_entry(u32 acpi_id)145 phys_cpuid_t __init acpi_map_madt_entry(u32 acpi_id)
146 {
147 struct acpi_table_madt *madt = NULL;
148 phys_cpuid_t rv;
149
150 acpi_get_table(ACPI_SIG_MADT, 0,
151 (struct acpi_table_header **)&madt);
152 if (!madt)
153 return PHYS_CPUID_INVALID;
154
155 rv = map_madt_entry(madt, 1, acpi_id);
156
157 acpi_put_table((struct acpi_table_header *)madt);
158
159 return rv;
160 }
161
map_mat_entry(acpi_handle handle,int type,u32 acpi_id)162 static phys_cpuid_t map_mat_entry(acpi_handle handle, int type, u32 acpi_id)
163 {
164 struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
165 union acpi_object *obj;
166 struct acpi_subtable_header *header;
167 phys_cpuid_t phys_id = PHYS_CPUID_INVALID;
168
169 if (ACPI_FAILURE(acpi_evaluate_object(handle, "_MAT", NULL, &buffer)))
170 goto exit;
171
172 if (!buffer.length || !buffer.pointer)
173 goto exit;
174
175 obj = buffer.pointer;
176 if (obj->type != ACPI_TYPE_BUFFER ||
177 obj->buffer.length < sizeof(struct acpi_subtable_header)) {
178 goto exit;
179 }
180
181 header = (struct acpi_subtable_header *)obj->buffer.pointer;
182 if (header->type == ACPI_MADT_TYPE_LOCAL_APIC)
183 map_lapic_id(header, acpi_id, &phys_id);
184 else if (header->type == ACPI_MADT_TYPE_LOCAL_SAPIC)
185 map_lsapic_id(header, type, acpi_id, &phys_id);
186 else if (header->type == ACPI_MADT_TYPE_LOCAL_X2APIC)
187 map_x2apic_id(header, type, acpi_id, &phys_id);
188 else if (header->type == ACPI_MADT_TYPE_GENERIC_INTERRUPT)
189 map_gicc_mpidr(header, type, acpi_id, &phys_id);
190
191 exit:
192 kfree(buffer.pointer);
193 return phys_id;
194 }
195
acpi_get_phys_id(acpi_handle handle,int type,u32 acpi_id)196 phys_cpuid_t acpi_get_phys_id(acpi_handle handle, int type, u32 acpi_id)
197 {
198 phys_cpuid_t phys_id;
199
200 phys_id = map_mat_entry(handle, type, acpi_id);
201 if (invalid_phys_cpuid(phys_id))
202 phys_id = map_madt_entry(get_madt_table(), type, acpi_id);
203
204 return phys_id;
205 }
206 EXPORT_SYMBOL_GPL(acpi_get_phys_id);
207
acpi_map_cpuid(phys_cpuid_t phys_id,u32 acpi_id)208 int acpi_map_cpuid(phys_cpuid_t phys_id, u32 acpi_id)
209 {
210 #ifdef CONFIG_SMP
211 int i;
212 #endif
213
214 if (invalid_phys_cpuid(phys_id)) {
215 /*
216 * On UP processor, there is no _MAT or MADT table.
217 * So above phys_id is always set to PHYS_CPUID_INVALID.
218 *
219 * BIOS may define multiple CPU handles even for UP processor.
220 * For example,
221 *
222 * Scope (_PR)
223 * {
224 * Processor (CPU0, 0x00, 0x00000410, 0x06) {}
225 * Processor (CPU1, 0x01, 0x00000410, 0x06) {}
226 * Processor (CPU2, 0x02, 0x00000410, 0x06) {}
227 * Processor (CPU3, 0x03, 0x00000410, 0x06) {}
228 * }
229 *
230 * Ignores phys_id and always returns 0 for the processor
231 * handle with acpi id 0 if nr_cpu_ids is 1.
232 * This should be the case if SMP tables are not found.
233 * Return -EINVAL for other CPU's handle.
234 */
235 if (nr_cpu_ids <= 1 && acpi_id == 0)
236 return acpi_id;
237 else
238 return -EINVAL;
239 }
240
241 #ifdef CONFIG_SMP
242 for_each_possible_cpu(i) {
243 if (cpu_physical_id(i) == phys_id)
244 return i;
245 }
246 #else
247 /* In UP kernel, only processor 0 is valid */
248 if (phys_id == 0)
249 return phys_id;
250 #endif
251 return -ENODEV;
252 }
253
acpi_get_cpuid(acpi_handle handle,int type,u32 acpi_id)254 int acpi_get_cpuid(acpi_handle handle, int type, u32 acpi_id)
255 {
256 phys_cpuid_t phys_id;
257
258 phys_id = acpi_get_phys_id(handle, type, acpi_id);
259
260 return acpi_map_cpuid(phys_id, acpi_id);
261 }
262 EXPORT_SYMBOL_GPL(acpi_get_cpuid);
263
264 #ifdef CONFIG_ACPI_HOTPLUG_IOAPIC
get_ioapic_id(struct acpi_subtable_header * entry,u32 gsi_base,u64 * phys_addr,int * ioapic_id)265 static int get_ioapic_id(struct acpi_subtable_header *entry, u32 gsi_base,
266 u64 *phys_addr, int *ioapic_id)
267 {
268 struct acpi_madt_io_apic *ioapic = (struct acpi_madt_io_apic *)entry;
269
270 if (ioapic->global_irq_base != gsi_base)
271 return 0;
272
273 *phys_addr = ioapic->address;
274 *ioapic_id = ioapic->id;
275 return 1;
276 }
277
parse_madt_ioapic_entry(u32 gsi_base,u64 * phys_addr)278 static int parse_madt_ioapic_entry(u32 gsi_base, u64 *phys_addr)
279 {
280 struct acpi_subtable_header *hdr;
281 unsigned long madt_end, entry;
282 struct acpi_table_madt *madt;
283 int apic_id = -1;
284
285 madt = get_madt_table();
286 if (!madt)
287 return apic_id;
288
289 entry = (unsigned long)madt;
290 madt_end = entry + madt->header.length;
291
292 /* Parse all entries looking for a match. */
293 entry += sizeof(struct acpi_table_madt);
294 while (entry + sizeof(struct acpi_subtable_header) < madt_end) {
295 hdr = (struct acpi_subtable_header *)entry;
296 if (hdr->type == ACPI_MADT_TYPE_IO_APIC &&
297 get_ioapic_id(hdr, gsi_base, phys_addr, &apic_id))
298 break;
299 else
300 entry += hdr->length;
301 }
302
303 return apic_id;
304 }
305
parse_mat_ioapic_entry(acpi_handle handle,u32 gsi_base,u64 * phys_addr)306 static int parse_mat_ioapic_entry(acpi_handle handle, u32 gsi_base,
307 u64 *phys_addr)
308 {
309 struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
310 struct acpi_subtable_header *header;
311 union acpi_object *obj;
312 int apic_id = -1;
313
314 if (ACPI_FAILURE(acpi_evaluate_object(handle, "_MAT", NULL, &buffer)))
315 goto exit;
316
317 if (!buffer.length || !buffer.pointer)
318 goto exit;
319
320 obj = buffer.pointer;
321 if (obj->type != ACPI_TYPE_BUFFER ||
322 obj->buffer.length < sizeof(struct acpi_subtable_header))
323 goto exit;
324
325 header = (struct acpi_subtable_header *)obj->buffer.pointer;
326 if (header->type == ACPI_MADT_TYPE_IO_APIC)
327 get_ioapic_id(header, gsi_base, phys_addr, &apic_id);
328
329 exit:
330 kfree(buffer.pointer);
331 return apic_id;
332 }
333
334 /**
335 * acpi_get_ioapic_id - Get IOAPIC ID and physical address matching @gsi_base
336 * @handle: ACPI object for IOAPIC device
337 * @gsi_base: GSI base to match with
338 * @phys_addr: Pointer to store physical address of matching IOAPIC record
339 *
340 * Walk resources returned by ACPI_MAT method, then ACPI MADT table, to search
341 * for an ACPI IOAPIC record matching @gsi_base.
342 * Return IOAPIC id and store physical address in @phys_addr if found a match,
343 * otherwise return <0.
344 */
acpi_get_ioapic_id(acpi_handle handle,u32 gsi_base,u64 * phys_addr)345 int acpi_get_ioapic_id(acpi_handle handle, u32 gsi_base, u64 *phys_addr)
346 {
347 int apic_id;
348
349 apic_id = parse_mat_ioapic_entry(handle, gsi_base, phys_addr);
350 if (apic_id == -1)
351 apic_id = parse_madt_ioapic_entry(gsi_base, phys_addr);
352
353 return apic_id;
354 }
355 #endif /* CONFIG_ACPI_HOTPLUG_IOAPIC */
356