Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
tjh.dev
kernel
os
linux
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#include <linux/export.h>
9#include <linux/acpi.h>
10#include <acpi/processor.h>
11
12#define _COMPONENT ACPI_PROCESSOR_COMPONENT
13ACPI_MODULE_NAME("processor_core");
14
15static int map_lapic_id(struct acpi_subtable_header *entry,
16 u32 acpi_id, int *apic_id)
17{
18 struct acpi_madt_local_apic *lapic =
19 container_of(entry, struct acpi_madt_local_apic, header);
20
21 if (!(lapic->lapic_flags & ACPI_MADT_ENABLED))
22 return -ENODEV;
23
24 if (lapic->processor_id != acpi_id)
25 return -EINVAL;
26
27 *apic_id = lapic->id;
28 return 0;
29}
30
31static int map_x2apic_id(struct acpi_subtable_header *entry,
32 int device_declaration, u32 acpi_id, int *apic_id)
33{
34 struct acpi_madt_local_x2apic *apic =
35 container_of(entry, struct acpi_madt_local_x2apic, header);
36
37 if (!(apic->lapic_flags & ACPI_MADT_ENABLED))
38 return -ENODEV;
39
40 if (device_declaration && (apic->uid == acpi_id)) {
41 *apic_id = apic->local_apic_id;
42 return 0;
43 }
44
45 return -EINVAL;
46}
47
48static int map_lsapic_id(struct acpi_subtable_header *entry,
49 int device_declaration, u32 acpi_id, int *apic_id)
50{
51 struct acpi_madt_local_sapic *lsapic =
52 container_of(entry, struct acpi_madt_local_sapic, header);
53
54 if (!(lsapic->lapic_flags & ACPI_MADT_ENABLED))
55 return -ENODEV;
56
57 if (device_declaration) {
58 if ((entry->length < 16) || (lsapic->uid != acpi_id))
59 return -EINVAL;
60 } else if (lsapic->processor_id != acpi_id)
61 return -EINVAL;
62
63 *apic_id = (lsapic->id << 8) | lsapic->eid;
64 return 0;
65}
66
67static int map_madt_entry(int type, u32 acpi_id)
68{
69 unsigned long madt_end, entry;
70 static struct acpi_table_madt *madt;
71 static int read_madt;
72 int phys_id = -1; /* CPU hardware ID */
73
74 if (!read_madt) {
75 if (ACPI_FAILURE(acpi_get_table(ACPI_SIG_MADT, 0,
76 (struct acpi_table_header **)&madt)))
77 madt = NULL;
78 read_madt++;
79 }
80
81 if (!madt)
82 return phys_id;
83
84 entry = (unsigned long)madt;
85 madt_end = entry + madt->header.length;
86
87 /* Parse all entries looking for a match. */
88
89 entry += sizeof(struct acpi_table_madt);
90 while (entry + sizeof(struct acpi_subtable_header) < madt_end) {
91 struct acpi_subtable_header *header =
92 (struct acpi_subtable_header *)entry;
93 if (header->type == ACPI_MADT_TYPE_LOCAL_APIC) {
94 if (!map_lapic_id(header, acpi_id, &phys_id))
95 break;
96 } else if (header->type == ACPI_MADT_TYPE_LOCAL_X2APIC) {
97 if (!map_x2apic_id(header, type, acpi_id, &phys_id))
98 break;
99 } else if (header->type == ACPI_MADT_TYPE_LOCAL_SAPIC) {
100 if (!map_lsapic_id(header, type, acpi_id, &phys_id))
101 break;
102 }
103 entry += header->length;
104 }
105 return phys_id;
106}
107
108static int map_mat_entry(acpi_handle handle, int type, u32 acpi_id)
109{
110 struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
111 union acpi_object *obj;
112 struct acpi_subtable_header *header;
113 int phys_id = -1;
114
115 if (ACPI_FAILURE(acpi_evaluate_object(handle, "_MAT", NULL, &buffer)))
116 goto exit;
117
118 if (!buffer.length || !buffer.pointer)
119 goto exit;
120
121 obj = buffer.pointer;
122 if (obj->type != ACPI_TYPE_BUFFER ||
123 obj->buffer.length < sizeof(struct acpi_subtable_header)) {
124 goto exit;
125 }
126
127 header = (struct acpi_subtable_header *)obj->buffer.pointer;
128 if (header->type == ACPI_MADT_TYPE_LOCAL_APIC)
129 map_lapic_id(header, acpi_id, &phys_id);
130 else if (header->type == ACPI_MADT_TYPE_LOCAL_SAPIC)
131 map_lsapic_id(header, type, acpi_id, &phys_id);
132 else if (header->type == ACPI_MADT_TYPE_LOCAL_X2APIC)
133 map_x2apic_id(header, type, acpi_id, &phys_id);
134
135exit:
136 kfree(buffer.pointer);
137 return phys_id;
138}
139
140int acpi_get_phys_id(acpi_handle handle, int type, u32 acpi_id)
141{
142 int phys_id;
143
144 phys_id = map_mat_entry(handle, type, acpi_id);
145 if (phys_id == -1)
146 phys_id = map_madt_entry(type, acpi_id);
147
148 return phys_id;
149}
150
151int acpi_map_cpuid(int phys_id, u32 acpi_id)
152{
153#ifdef CONFIG_SMP
154 int i;
155#endif
156
157 if (phys_id == -1) {
158 /*
159 * On UP processor, there is no _MAT or MADT table.
160 * So above phys_id is always set to -1.
161 *
162 * BIOS may define multiple CPU handles even for UP processor.
163 * For example,
164 *
165 * Scope (_PR)
166 * {
167 * Processor (CPU0, 0x00, 0x00000410, 0x06) {}
168 * Processor (CPU1, 0x01, 0x00000410, 0x06) {}
169 * Processor (CPU2, 0x02, 0x00000410, 0x06) {}
170 * Processor (CPU3, 0x03, 0x00000410, 0x06) {}
171 * }
172 *
173 * Ignores phys_id and always returns 0 for the processor
174 * handle with acpi id 0 if nr_cpu_ids is 1.
175 * This should be the case if SMP tables are not found.
176 * Return -1 for other CPU's handle.
177 */
178 if (nr_cpu_ids <= 1 && acpi_id == 0)
179 return acpi_id;
180 else
181 return phys_id;
182 }
183
184#ifdef CONFIG_SMP
185 for_each_possible_cpu(i) {
186 if (cpu_physical_id(i) == phys_id)
187 return i;
188 }
189#else
190 /* In UP kernel, only processor 0 is valid */
191 if (phys_id == 0)
192 return phys_id;
193#endif
194 return -1;
195}
196
197int acpi_get_cpuid(acpi_handle handle, int type, u32 acpi_id)
198{
199 int phys_id;
200
201 phys_id = acpi_get_phys_id(handle, type, acpi_id);
202
203 return acpi_map_cpuid(phys_id, acpi_id);
204}
205EXPORT_SYMBOL_GPL(acpi_get_cpuid);