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(struct acpi_table_madt *madt,
112 int type, u32 acpi_id)
113{
114 unsigned long madt_end, entry;
115 phys_cpuid_t phys_id = PHYS_CPUID_INVALID; /* CPU hardware ID */
116
117 if (!madt)
118 return phys_id;
119
120 entry = (unsigned long)madt;
121 madt_end = entry + madt->header.length;
122
123 /* Parse all entries looking for a match. */
124
125 entry += sizeof(struct acpi_table_madt);
126 while (entry + sizeof(struct acpi_subtable_header) < madt_end) {
127 struct acpi_subtable_header *header =
128 (struct acpi_subtable_header *)entry;
129 if (header->type == ACPI_MADT_TYPE_LOCAL_APIC) {
130 if (!map_lapic_id(header, acpi_id, &phys_id))
131 break;
132 } else if (header->type == ACPI_MADT_TYPE_LOCAL_X2APIC) {
133 if (!map_x2apic_id(header, type, acpi_id, &phys_id))
134 break;
135 } else if (header->type == ACPI_MADT_TYPE_LOCAL_SAPIC) {
136 if (!map_lsapic_id(header, type, acpi_id, &phys_id))
137 break;
138 } else if (header->type == ACPI_MADT_TYPE_GENERIC_INTERRUPT) {
139 if (!map_gicc_mpidr(header, type, acpi_id, &phys_id))
140 break;
141 }
142 entry += header->length;
143 }
144 return phys_id;
145}
146
147phys_cpuid_t __init acpi_map_madt_entry(u32 acpi_id)
148{
149 struct acpi_table_madt *madt = NULL;
150 phys_cpuid_t rv;
151
152 acpi_get_table(ACPI_SIG_MADT, 0,
153 (struct acpi_table_header **)&madt);
154 if (!madt)
155 return PHYS_CPUID_INVALID;
156
157 rv = map_madt_entry(madt, 1, acpi_id);
158
159 acpi_put_table((struct acpi_table_header *)madt);
160
161 return rv;
162}
163
164static phys_cpuid_t map_mat_entry(acpi_handle handle, int type, u32 acpi_id)
165{
166 struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
167 union acpi_object *obj;
168 struct acpi_subtable_header *header;
169 phys_cpuid_t phys_id = PHYS_CPUID_INVALID;
170
171 if (ACPI_FAILURE(acpi_evaluate_object(handle, "_MAT", NULL, &buffer)))
172 goto exit;
173
174 if (!buffer.length || !buffer.pointer)
175 goto exit;
176
177 obj = buffer.pointer;
178 if (obj->type != ACPI_TYPE_BUFFER ||
179 obj->buffer.length < sizeof(struct acpi_subtable_header)) {
180 goto exit;
181 }
182
183 header = (struct acpi_subtable_header *)obj->buffer.pointer;
184 if (header->type == ACPI_MADT_TYPE_LOCAL_APIC)
185 map_lapic_id(header, acpi_id, &phys_id);
186 else if (header->type == ACPI_MADT_TYPE_LOCAL_SAPIC)
187 map_lsapic_id(header, type, acpi_id, &phys_id);
188 else if (header->type == ACPI_MADT_TYPE_LOCAL_X2APIC)
189 map_x2apic_id(header, type, acpi_id, &phys_id);
190 else if (header->type == ACPI_MADT_TYPE_GENERIC_INTERRUPT)
191 map_gicc_mpidr(header, type, acpi_id, &phys_id);
192
193exit:
194 kfree(buffer.pointer);
195 return phys_id;
196}
197
198phys_cpuid_t acpi_get_phys_id(acpi_handle handle, int type, u32 acpi_id)
199{
200 phys_cpuid_t phys_id;
201
202 phys_id = map_mat_entry(handle, type, acpi_id);
203 if (invalid_phys_cpuid(phys_id))
204 phys_id = map_madt_entry(get_madt_table(), type, acpi_id);
205
206 return phys_id;
207}
208EXPORT_SYMBOL_GPL(acpi_get_phys_id);
209
210int acpi_map_cpuid(phys_cpuid_t phys_id, u32 acpi_id)
211{
212#ifdef CONFIG_SMP
213 int i;
214#endif
215
216 if (invalid_phys_cpuid(phys_id)) {
217 /*
218 * On UP processor, there is no _MAT or MADT table.
219 * So above phys_id is always set to PHYS_CPUID_INVALID.
220 *
221 * BIOS may define multiple CPU handles even for UP processor.
222 * For example,
223 *
224 * Scope (_PR)
225 * {
226 * Processor (CPU0, 0x00, 0x00000410, 0x06) {}
227 * Processor (CPU1, 0x01, 0x00000410, 0x06) {}
228 * Processor (CPU2, 0x02, 0x00000410, 0x06) {}
229 * Processor (CPU3, 0x03, 0x00000410, 0x06) {}
230 * }
231 *
232 * Ignores phys_id and always returns 0 for the processor
233 * handle with acpi id 0 if nr_cpu_ids is 1.
234 * This should be the case if SMP tables are not found.
235 * Return -EINVAL for other CPU's handle.
236 */
237 if (nr_cpu_ids <= 1 && acpi_id == 0)
238 return acpi_id;
239 else
240 return -EINVAL;
241 }
242
243#ifdef CONFIG_SMP
244 for_each_possible_cpu(i) {
245 if (cpu_physical_id(i) == phys_id)
246 return i;
247 }
248#else
249 /* In UP kernel, only processor 0 is valid */
250 if (phys_id == 0)
251 return phys_id;
252#endif
253 return -ENODEV;
254}
255
256int acpi_get_cpuid(acpi_handle handle, int type, u32 acpi_id)
257{
258 phys_cpuid_t phys_id;
259
260 phys_id = acpi_get_phys_id(handle, type, acpi_id);
261
262 return acpi_map_cpuid(phys_id, acpi_id);
263}
264EXPORT_SYMBOL_GPL(acpi_get_cpuid);
265
266#ifdef CONFIG_ACPI_HOTPLUG_IOAPIC
267static int get_ioapic_id(struct acpi_subtable_header *entry, u32 gsi_base,
268 u64 *phys_addr, int *ioapic_id)
269{
270 struct acpi_madt_io_apic *ioapic = (struct acpi_madt_io_apic *)entry;
271
272 if (ioapic->global_irq_base != gsi_base)
273 return 0;
274
275 *phys_addr = ioapic->address;
276 *ioapic_id = ioapic->id;
277 return 1;
278}
279
280static int parse_madt_ioapic_entry(u32 gsi_base, u64 *phys_addr)
281{
282 struct acpi_subtable_header *hdr;
283 unsigned long madt_end, entry;
284 struct acpi_table_madt *madt;
285 int apic_id = -1;
286
287 madt = get_madt_table();
288 if (!madt)
289 return apic_id;
290
291 entry = (unsigned long)madt;
292 madt_end = entry + madt->header.length;
293
294 /* Parse all entries looking for a match. */
295 entry += sizeof(struct acpi_table_madt);
296 while (entry + sizeof(struct acpi_subtable_header) < madt_end) {
297 hdr = (struct acpi_subtable_header *)entry;
298 if (hdr->type == ACPI_MADT_TYPE_IO_APIC &&
299 get_ioapic_id(hdr, gsi_base, phys_addr, &apic_id))
300 break;
301 else
302 entry += hdr->length;
303 }
304
305 return apic_id;
306}
307
308static int parse_mat_ioapic_entry(acpi_handle handle, u32 gsi_base,
309 u64 *phys_addr)
310{
311 struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
312 struct acpi_subtable_header *header;
313 union acpi_object *obj;
314 int apic_id = -1;
315
316 if (ACPI_FAILURE(acpi_evaluate_object(handle, "_MAT", NULL, &buffer)))
317 goto exit;
318
319 if (!buffer.length || !buffer.pointer)
320 goto exit;
321
322 obj = buffer.pointer;
323 if (obj->type != ACPI_TYPE_BUFFER ||
324 obj->buffer.length < sizeof(struct acpi_subtable_header))
325 goto exit;
326
327 header = (struct acpi_subtable_header *)obj->buffer.pointer;
328 if (header->type == ACPI_MADT_TYPE_IO_APIC)
329 get_ioapic_id(header, gsi_base, phys_addr, &apic_id);
330
331exit:
332 kfree(buffer.pointer);
333 return apic_id;
334}
335
336/**
337 * acpi_get_ioapic_id - Get IOAPIC ID and physical address matching @gsi_base
338 * @handle: ACPI object for IOAPIC device
339 * @gsi_base: GSI base to match with
340 * @phys_addr: Pointer to store physical address of matching IOAPIC record
341 *
342 * Walk resources returned by ACPI_MAT method, then ACPI MADT table, to search
343 * for an ACPI IOAPIC record matching @gsi_base.
344 * Return IOAPIC id and store physical address in @phys_addr if found a match,
345 * otherwise return <0.
346 */
347int acpi_get_ioapic_id(acpi_handle handle, u32 gsi_base, u64 *phys_addr)
348{
349 int apic_id;
350
351 apic_id = parse_mat_ioapic_entry(handle, gsi_base, phys_addr);
352 if (apic_id == -1)
353 apic_id = parse_madt_ioapic_entry(gsi_base, phys_addr);
354
355 return apic_id;
356}
357#endif /* CONFIG_ACPI_HOTPLUG_IOAPIC */
358