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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>
12#include <linux/module.h>
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>
21
22#include <asm/setup.h>
23#include <asm/page.h>
24#include <asm/mach/arch.h>
25#include <asm/mach-types.h>
26
27void __init early_init_dt_add_memory_arch(u64 base, u64 size)
28{
29 arm_add_memory(base, size);
30}
31
32void * __init early_init_dt_alloc_memory_arch(u64 size, u64 align)
33{
34 return alloc_bootmem_align(size, align);
35}
36
37void __init arm_dt_memblock_reserve(void)
38{
39 u64 *reserve_map, base, size;
40
41 if (!initial_boot_params)
42 return;
43
44 /* Reserve the dtb region */
45 memblock_reserve(virt_to_phys(initial_boot_params),
46 be32_to_cpu(initial_boot_params->totalsize));
47
48 /*
49 * Process the reserve map. This will probably overlap the initrd
50 * and dtb locations which are already reserved, but overlaping
51 * doesn't hurt anything
52 */
53 reserve_map = ((void*)initial_boot_params) +
54 be32_to_cpu(initial_boot_params->off_mem_rsvmap);
55 while (1) {
56 base = be64_to_cpup(reserve_map++);
57 size = be64_to_cpup(reserve_map++);
58 if (!size)
59 break;
60 memblock_reserve(base, size);
61 }
62}
63
64/**
65 * setup_machine_fdt - Machine setup when an dtb was passed to the kernel
66 * @dt_phys: physical address of dt blob
67 *
68 * If a dtb was passed to the kernel in r2, then use it to choose the
69 * correct machine_desc and to setup the system.
70 */
71struct machine_desc * __init setup_machine_fdt(unsigned int dt_phys)
72{
73 struct boot_param_header *devtree;
74 struct machine_desc *mdesc, *mdesc_best = NULL;
75 unsigned int score, mdesc_score = ~1;
76 unsigned long dt_root;
77 const char *model;
78
79 if (!dt_phys)
80 return NULL;
81
82 devtree = phys_to_virt(dt_phys);
83
84 /* check device tree validity */
85 if (be32_to_cpu(devtree->magic) != OF_DT_HEADER)
86 return NULL;
87
88 /* Search the mdescs for the 'best' compatible value match */
89 initial_boot_params = devtree;
90 dt_root = of_get_flat_dt_root();
91 for_each_machine_desc(mdesc) {
92 score = of_flat_dt_match(dt_root, mdesc->dt_compat);
93 if (score > 0 && score < mdesc_score) {
94 mdesc_best = mdesc;
95 mdesc_score = score;
96 }
97 }
98 if (!mdesc_best) {
99 const char *prop;
100 long size;
101
102 early_print("\nError: unrecognized/unsupported "
103 "device tree compatible list:\n[ ");
104
105 prop = of_get_flat_dt_prop(dt_root, "compatible", &size);
106 while (size > 0) {
107 early_print("'%s' ", prop);
108 size -= strlen(prop) + 1;
109 prop += strlen(prop) + 1;
110 }
111 early_print("]\n\n");
112
113 dump_machine_table(); /* does not return */
114 }
115
116 model = of_get_flat_dt_prop(dt_root, "model", NULL);
117 if (!model)
118 model = of_get_flat_dt_prop(dt_root, "compatible", NULL);
119 if (!model)
120 model = "<unknown>";
121 pr_info("Machine: %s, model: %s\n", mdesc_best->name, model);
122
123 /* Retrieve various information from the /chosen node */
124 of_scan_flat_dt(early_init_dt_scan_chosen, boot_command_line);
125 /* Initialize {size,address}-cells info */
126 of_scan_flat_dt(early_init_dt_scan_root, NULL);
127 /* Setup memory, calling early_init_dt_add_memory_arch */
128 of_scan_flat_dt(early_init_dt_scan_memory, NULL);
129
130 /* Change machine number to match the mdesc we're using */
131 __machine_arch_type = mdesc_best->nr;
132
133 return mdesc_best;
134}
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>
12#include <linux/export.h>
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>
21#include <linux/smp.h>
22
23#include <asm/cputype.h>
24#include <asm/setup.h>
25#include <asm/page.h>
26#include <asm/smp_plat.h>
27#include <asm/mach/arch.h>
28#include <asm/mach-types.h>
29
30void __init early_init_dt_add_memory_arch(u64 base, u64 size)
31{
32 arm_add_memory(base, size);
33}
34
35void * __init early_init_dt_alloc_memory_arch(u64 size, u64 align)
36{
37 return memblock_virt_alloc(size, align);
38}
39
40void __init arm_dt_memblock_reserve(void)
41{
42 u64 *reserve_map, base, size;
43
44 if (!initial_boot_params)
45 return;
46
47 /* Reserve the dtb region */
48 memblock_reserve(virt_to_phys(initial_boot_params),
49 be32_to_cpu(initial_boot_params->totalsize));
50
51 /*
52 * Process the reserve map. This will probably overlap the initrd
53 * and dtb locations which are already reserved, but overlaping
54 * doesn't hurt anything
55 */
56 reserve_map = ((void*)initial_boot_params) +
57 be32_to_cpu(initial_boot_params->off_mem_rsvmap);
58 while (1) {
59 base = be64_to_cpup(reserve_map++);
60 size = be64_to_cpup(reserve_map++);
61 if (!size)
62 break;
63 memblock_reserve(base, size);
64 }
65}
66
67#ifdef CONFIG_SMP
68extern struct of_cpu_method __cpu_method_of_table_begin[];
69extern struct of_cpu_method __cpu_method_of_table_end[];
70
71static int __init set_smp_ops_by_method(struct device_node *node)
72{
73 const char *method;
74 struct of_cpu_method *m = __cpu_method_of_table_begin;
75
76 if (of_property_read_string(node, "enable-method", &method))
77 return 0;
78
79 for (; m < __cpu_method_of_table_end; m++)
80 if (!strcmp(m->method, method)) {
81 smp_set_ops(m->ops);
82 return 1;
83 }
84
85 return 0;
86}
87#else
88static inline int set_smp_ops_by_method(struct device_node *node)
89{
90 return 1;
91}
92#endif
93
94
95/*
96 * arm_dt_init_cpu_maps - Function retrieves cpu nodes from the device tree
97 * and builds the cpu logical map array containing MPIDR values related to
98 * logical cpus
99 *
100 * Updates the cpu possible mask with the number of parsed cpu nodes
101 */
102void __init arm_dt_init_cpu_maps(void)
103{
104 /*
105 * Temp logical map is initialized with UINT_MAX values that are
106 * considered invalid logical map entries since the logical map must
107 * contain a list of MPIDR[23:0] values where MPIDR[31:24] must
108 * read as 0.
109 */
110 struct device_node *cpu, *cpus;
111 int found_method = 0;
112 u32 i, j, cpuidx = 1;
113 u32 mpidr = is_smp() ? read_cpuid_mpidr() & MPIDR_HWID_BITMASK : 0;
114
115 u32 tmp_map[NR_CPUS] = { [0 ... NR_CPUS-1] = MPIDR_INVALID };
116 bool bootcpu_valid = false;
117 cpus = of_find_node_by_path("/cpus");
118
119 if (!cpus)
120 return;
121
122 for_each_child_of_node(cpus, cpu) {
123 u32 hwid;
124
125 if (of_node_cmp(cpu->type, "cpu"))
126 continue;
127
128 pr_debug(" * %s...\n", cpu->full_name);
129 /*
130 * A device tree containing CPU nodes with missing "reg"
131 * properties is considered invalid to build the
132 * cpu_logical_map.
133 */
134 if (of_property_read_u32(cpu, "reg", &hwid)) {
135 pr_debug(" * %s missing reg property\n",
136 cpu->full_name);
137 return;
138 }
139
140 /*
141 * 8 MSBs must be set to 0 in the DT since the reg property
142 * defines the MPIDR[23:0].
143 */
144 if (hwid & ~MPIDR_HWID_BITMASK)
145 return;
146
147 /*
148 * Duplicate MPIDRs are a recipe for disaster.
149 * Scan all initialized entries and check for
150 * duplicates. If any is found just bail out.
151 * temp values were initialized to UINT_MAX
152 * to avoid matching valid MPIDR[23:0] values.
153 */
154 for (j = 0; j < cpuidx; j++)
155 if (WARN(tmp_map[j] == hwid, "Duplicate /cpu reg "
156 "properties in the DT\n"))
157 return;
158
159 /*
160 * Build a stashed array of MPIDR values. Numbering scheme
161 * requires that if detected the boot CPU must be assigned
162 * logical id 0. Other CPUs get sequential indexes starting
163 * from 1. If a CPU node with a reg property matching the
164 * boot CPU MPIDR is detected, this is recorded so that the
165 * logical map built from DT is validated and can be used
166 * to override the map created in smp_setup_processor_id().
167 */
168 if (hwid == mpidr) {
169 i = 0;
170 bootcpu_valid = true;
171 } else {
172 i = cpuidx++;
173 }
174
175 if (WARN(cpuidx > nr_cpu_ids, "DT /cpu %u nodes greater than "
176 "max cores %u, capping them\n",
177 cpuidx, nr_cpu_ids)) {
178 cpuidx = nr_cpu_ids;
179 break;
180 }
181
182 tmp_map[i] = hwid;
183
184 if (!found_method)
185 found_method = set_smp_ops_by_method(cpu);
186 }
187
188 /*
189 * Fallback to an enable-method in the cpus node if nothing found in
190 * a cpu node.
191 */
192 if (!found_method)
193 set_smp_ops_by_method(cpus);
194
195 if (!bootcpu_valid) {
196 pr_warn("DT missing boot CPU MPIDR[23:0], fall back to default cpu_logical_map\n");
197 return;
198 }
199
200 /*
201 * Since the boot CPU node contains proper data, and all nodes have
202 * a reg property, the DT CPU list can be considered valid and the
203 * logical map created in smp_setup_processor_id() can be overridden
204 */
205 for (i = 0; i < cpuidx; i++) {
206 set_cpu_possible(i, true);
207 cpu_logical_map(i) = tmp_map[i];
208 pr_debug("cpu logical map 0x%x\n", cpu_logical_map(i));
209 }
210}
211
212bool arch_match_cpu_phys_id(int cpu, u64 phys_id)
213{
214 return phys_id == cpu_logical_map(cpu);
215}
216
217static const void * __init arch_get_next_mach(const char *const **match)
218{
219 static const struct machine_desc *mdesc = __arch_info_begin;
220 const struct machine_desc *m = mdesc;
221
222 if (m >= __arch_info_end)
223 return NULL;
224
225 mdesc++;
226 *match = m->dt_compat;
227 return m;
228}
229
230/**
231 * setup_machine_fdt - Machine setup when an dtb was passed to the kernel
232 * @dt_phys: physical address of dt blob
233 *
234 * If a dtb was passed to the kernel in r2, then use it to choose the
235 * correct machine_desc and to setup the system.
236 */
237const struct machine_desc * __init setup_machine_fdt(unsigned int dt_phys)
238{
239 const struct machine_desc *mdesc, *mdesc_best = NULL;
240
241#ifdef CONFIG_ARCH_MULTIPLATFORM
242 DT_MACHINE_START(GENERIC_DT, "Generic DT based system")
243 MACHINE_END
244
245 mdesc_best = &__mach_desc_GENERIC_DT;
246#endif
247
248 if (!dt_phys || !early_init_dt_scan(phys_to_virt(dt_phys)))
249 return NULL;
250
251 mdesc = of_flat_dt_match_machine(mdesc_best, arch_get_next_mach);
252
253 if (!mdesc) {
254 const char *prop;
255 long size;
256 unsigned long dt_root;
257
258 early_print("\nError: unrecognized/unsupported "
259 "device tree compatible list:\n[ ");
260
261 dt_root = of_get_flat_dt_root();
262 prop = of_get_flat_dt_prop(dt_root, "compatible", &size);
263 while (size > 0) {
264 early_print("'%s' ", prop);
265 size -= strlen(prop) + 1;
266 prop += strlen(prop) + 1;
267 }
268 early_print("]\n\n");
269
270 dump_machine_table(); /* does not return */
271 }
272
273 /* Change machine number to match the mdesc we're using */
274 __machine_arch_type = mdesc->nr;
275
276 return mdesc;
277}