Commit | Line | Data |
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9eb8f674 GL |
1 | /* |
2 | * linux/arch/arm/kernel/devtree.c | |
3 | * | |
4 | * Copyright (C) 2009 Canonical Ltd. <jeremy.kerr@canonical.com> | |
5 | * | |
6 | * This program is free software; you can redistribute it and/or modify | |
7 | * it under the terms of the GNU General Public License version 2 as | |
8 | * published by the Free Software Foundation. | |
9 | */ | |
10 | ||
11 | #include <linux/init.h> | |
ecea4ab6 | 12 | #include <linux/export.h> |
9eb8f674 GL |
13 | #include <linux/errno.h> |
14 | #include <linux/types.h> | |
15 | #include <linux/bootmem.h> | |
16 | #include <linux/memblock.h> | |
17 | #include <linux/of.h> | |
18 | #include <linux/of_fdt.h> | |
19 | #include <linux/of_irq.h> | |
20 | #include <linux/of_platform.h> | |
6c3ff8b1 | 21 | #include <linux/smp.h> |
9eb8f674 | 22 | |
a0ae0240 | 23 | #include <asm/cputype.h> |
9eb8f674 GL |
24 | #include <asm/setup.h> |
25 | #include <asm/page.h> | |
a0ae0240 | 26 | #include <asm/smp_plat.h> |
93c02ab4 GL |
27 | #include <asm/mach/arch.h> |
28 | #include <asm/mach-types.h> | |
9eb8f674 | 29 | |
9eb8f674 | 30 | |
6c3ff8b1 | 31 | #ifdef CONFIG_SMP |
9a721c41 RH |
32 | extern struct of_cpu_method __cpu_method_of_table[]; |
33 | ||
34 | static const struct of_cpu_method __cpu_method_of_table_sentinel | |
35 | __used __section(__cpu_method_of_table_end); | |
36 | ||
6c3ff8b1 SB |
37 | |
38 | static int __init set_smp_ops_by_method(struct device_node *node) | |
39 | { | |
40 | const char *method; | |
9a721c41 | 41 | struct of_cpu_method *m = __cpu_method_of_table; |
6c3ff8b1 SB |
42 | |
43 | if (of_property_read_string(node, "enable-method", &method)) | |
44 | return 0; | |
45 | ||
9a721c41 | 46 | for (; m->method; m++) |
6c3ff8b1 SB |
47 | if (!strcmp(m->method, method)) { |
48 | smp_set_ops(m->ops); | |
49 | return 1; | |
50 | } | |
51 | ||
52 | return 0; | |
53 | } | |
54 | #else | |
55 | static inline int set_smp_ops_by_method(struct device_node *node) | |
56 | { | |
57 | return 1; | |
58 | } | |
59 | #endif | |
60 | ||
61 | ||
a0ae0240 LP |
62 | /* |
63 | * arm_dt_init_cpu_maps - Function retrieves cpu nodes from the device tree | |
64 | * and builds the cpu logical map array containing MPIDR values related to | |
65 | * logical cpus | |
66 | * | |
67 | * Updates the cpu possible mask with the number of parsed cpu nodes | |
68 | */ | |
69 | void __init arm_dt_init_cpu_maps(void) | |
70 | { | |
71 | /* | |
72 | * Temp logical map is initialized with UINT_MAX values that are | |
73 | * considered invalid logical map entries since the logical map must | |
74 | * contain a list of MPIDR[23:0] values where MPIDR[31:24] must | |
75 | * read as 0. | |
76 | */ | |
77 | struct device_node *cpu, *cpus; | |
6c3ff8b1 | 78 | int found_method = 0; |
a0ae0240 LP |
79 | u32 i, j, cpuidx = 1; |
80 | u32 mpidr = is_smp() ? read_cpuid_mpidr() & MPIDR_HWID_BITMASK : 0; | |
81 | ||
18d7f152 | 82 | u32 tmp_map[NR_CPUS] = { [0 ... NR_CPUS-1] = MPIDR_INVALID }; |
a0ae0240 LP |
83 | bool bootcpu_valid = false; |
84 | cpus = of_find_node_by_path("/cpus"); | |
85 | ||
86 | if (!cpus) | |
87 | return; | |
88 | ||
89 | for_each_child_of_node(cpus, cpu) { | |
90 | u32 hwid; | |
91 | ||
1ba9bf0a LP |
92 | if (of_node_cmp(cpu->type, "cpu")) |
93 | continue; | |
94 | ||
a0ae0240 LP |
95 | pr_debug(" * %s...\n", cpu->full_name); |
96 | /* | |
97 | * A device tree containing CPU nodes with missing "reg" | |
98 | * properties is considered invalid to build the | |
99 | * cpu_logical_map. | |
100 | */ | |
101 | if (of_property_read_u32(cpu, "reg", &hwid)) { | |
102 | pr_debug(" * %s missing reg property\n", | |
103 | cpu->full_name); | |
104 | return; | |
105 | } | |
106 | ||
107 | /* | |
108 | * 8 MSBs must be set to 0 in the DT since the reg property | |
109 | * defines the MPIDR[23:0]. | |
110 | */ | |
111 | if (hwid & ~MPIDR_HWID_BITMASK) | |
112 | return; | |
113 | ||
114 | /* | |
115 | * Duplicate MPIDRs are a recipe for disaster. | |
116 | * Scan all initialized entries and check for | |
117 | * duplicates. If any is found just bail out. | |
118 | * temp values were initialized to UINT_MAX | |
119 | * to avoid matching valid MPIDR[23:0] values. | |
120 | */ | |
121 | for (j = 0; j < cpuidx; j++) | |
122 | if (WARN(tmp_map[j] == hwid, "Duplicate /cpu reg " | |
123 | "properties in the DT\n")) | |
124 | return; | |
125 | ||
126 | /* | |
127 | * Build a stashed array of MPIDR values. Numbering scheme | |
128 | * requires that if detected the boot CPU must be assigned | |
129 | * logical id 0. Other CPUs get sequential indexes starting | |
130 | * from 1. If a CPU node with a reg property matching the | |
131 | * boot CPU MPIDR is detected, this is recorded so that the | |
132 | * logical map built from DT is validated and can be used | |
133 | * to override the map created in smp_setup_processor_id(). | |
134 | */ | |
135 | if (hwid == mpidr) { | |
136 | i = 0; | |
137 | bootcpu_valid = true; | |
138 | } else { | |
139 | i = cpuidx++; | |
140 | } | |
141 | ||
ce7b1756 LP |
142 | if (WARN(cpuidx > nr_cpu_ids, "DT /cpu %u nodes greater than " |
143 | "max cores %u, capping them\n", | |
144 | cpuidx, nr_cpu_ids)) { | |
145 | cpuidx = nr_cpu_ids; | |
a0ae0240 | 146 | break; |
ce7b1756 LP |
147 | } |
148 | ||
149 | tmp_map[i] = hwid; | |
6c3ff8b1 SB |
150 | |
151 | if (!found_method) | |
152 | found_method = set_smp_ops_by_method(cpu); | |
a0ae0240 LP |
153 | } |
154 | ||
6c3ff8b1 SB |
155 | /* |
156 | * Fallback to an enable-method in the cpus node if nothing found in | |
157 | * a cpu node. | |
158 | */ | |
159 | if (!found_method) | |
160 | set_smp_ops_by_method(cpus); | |
161 | ||
8d5bc1a6 OJ |
162 | if (!bootcpu_valid) { |
163 | pr_warn("DT missing boot CPU MPIDR[23:0], fall back to default cpu_logical_map\n"); | |
a0ae0240 | 164 | return; |
8d5bc1a6 | 165 | } |
a0ae0240 LP |
166 | |
167 | /* | |
168 | * Since the boot CPU node contains proper data, and all nodes have | |
169 | * a reg property, the DT CPU list can be considered valid and the | |
170 | * logical map created in smp_setup_processor_id() can be overridden | |
171 | */ | |
172 | for (i = 0; i < cpuidx; i++) { | |
173 | set_cpu_possible(i, true); | |
174 | cpu_logical_map(i) = tmp_map[i]; | |
175 | pr_debug("cpu logical map 0x%x\n", cpu_logical_map(i)); | |
176 | } | |
177 | } | |
178 | ||
973e02c1 SK |
179 | bool arch_match_cpu_phys_id(int cpu, u64 phys_id) |
180 | { | |
e44ef891 | 181 | return phys_id == cpu_logical_map(cpu); |
973e02c1 SK |
182 | } |
183 | ||
6d67a9f6 RH |
184 | static const void * __init arch_get_next_mach(const char *const **match) |
185 | { | |
186 | static const struct machine_desc *mdesc = __arch_info_begin; | |
187 | const struct machine_desc *m = mdesc; | |
188 | ||
189 | if (m >= __arch_info_end) | |
190 | return NULL; | |
191 | ||
192 | mdesc++; | |
193 | *match = m->dt_compat; | |
194 | return m; | |
195 | } | |
196 | ||
93c02ab4 GL |
197 | /** |
198 | * setup_machine_fdt - Machine setup when an dtb was passed to the kernel | |
199 | * @dt_phys: physical address of dt blob | |
200 | * | |
201 | * If a dtb was passed to the kernel in r2, then use it to choose the | |
202 | * correct machine_desc and to setup the system. | |
203 | */ | |
ff69a4c8 | 204 | const struct machine_desc * __init setup_machine_fdt(unsigned int dt_phys) |
93c02ab4 | 205 | { |
ff69a4c8 | 206 | const struct machine_desc *mdesc, *mdesc_best = NULL; |
93c02ab4 | 207 | |
883a106b AB |
208 | #ifdef CONFIG_ARCH_MULTIPLATFORM |
209 | DT_MACHINE_START(GENERIC_DT, "Generic DT based system") | |
210 | MACHINE_END | |
211 | ||
ff69a4c8 | 212 | mdesc_best = &__mach_desc_GENERIC_DT; |
883a106b AB |
213 | #endif |
214 | ||
5a12a597 | 215 | if (!dt_phys || !early_init_dt_verify(phys_to_virt(dt_phys))) |
f506cd48 NP |
216 | return NULL; |
217 | ||
6d67a9f6 | 218 | mdesc = of_flat_dt_match_machine(mdesc_best, arch_get_next_mach); |
93c02ab4 | 219 | |
6d67a9f6 | 220 | if (!mdesc) { |
93c02ab4 | 221 | const char *prop; |
9d0c4dfe | 222 | int size; |
6d67a9f6 | 223 | unsigned long dt_root; |
93c02ab4 GL |
224 | |
225 | early_print("\nError: unrecognized/unsupported " | |
226 | "device tree compatible list:\n[ "); | |
227 | ||
6d67a9f6 | 228 | dt_root = of_get_flat_dt_root(); |
93c02ab4 GL |
229 | prop = of_get_flat_dt_prop(dt_root, "compatible", &size); |
230 | while (size > 0) { | |
231 | early_print("'%s' ", prop); | |
232 | size -= strlen(prop) + 1; | |
233 | prop += strlen(prop) + 1; | |
234 | } | |
235 | early_print("]\n\n"); | |
236 | ||
237 | dump_machine_table(); /* does not return */ | |
238 | } | |
239 | ||
5a12a597 LA |
240 | /* We really don't want to do this, but sometimes firmware provides buggy data */ |
241 | if (mdesc->dt_fixup) | |
242 | mdesc->dt_fixup(); | |
243 | ||
244 | early_init_dt_scan_nodes(); | |
245 | ||
93c02ab4 | 246 | /* Change machine number to match the mdesc we're using */ |
6d67a9f6 | 247 | __machine_arch_type = mdesc->nr; |
93c02ab4 | 248 | |
6d67a9f6 | 249 | return mdesc; |
93c02ab4 | 250 | } |