Loading...
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/prom.h>
27#include <asm/smp_plat.h>
28#include <asm/mach/arch.h>
29#include <asm/mach-types.h>
30
31
32#ifdef CONFIG_SMP
33extern struct of_cpu_method __cpu_method_of_table[];
34
35static const struct of_cpu_method __cpu_method_of_table_sentinel
36 __used __section(__cpu_method_of_table_end);
37
38
39static int __init set_smp_ops_by_method(struct device_node *node)
40{
41 const char *method;
42 struct of_cpu_method *m = __cpu_method_of_table;
43
44 if (of_property_read_string(node, "enable-method", &method))
45 return 0;
46
47 for (; m->method; m++)
48 if (!strcmp(m->method, method)) {
49 smp_set_ops(m->ops);
50 return 1;
51 }
52
53 return 0;
54}
55#else
56static inline int set_smp_ops_by_method(struct device_node *node)
57{
58 return 1;
59}
60#endif
61
62
63/*
64 * arm_dt_init_cpu_maps - Function retrieves cpu nodes from the device tree
65 * and builds the cpu logical map array containing MPIDR values related to
66 * logical cpus
67 *
68 * Updates the cpu possible mask with the number of parsed cpu nodes
69 */
70void __init arm_dt_init_cpu_maps(void)
71{
72 /*
73 * Temp logical map is initialized with UINT_MAX values that are
74 * considered invalid logical map entries since the logical map must
75 * contain a list of MPIDR[23:0] values where MPIDR[31:24] must
76 * read as 0.
77 */
78 struct device_node *cpu, *cpus;
79 int found_method = 0;
80 u32 i, j, cpuidx = 1;
81 u32 mpidr = is_smp() ? read_cpuid_mpidr() & MPIDR_HWID_BITMASK : 0;
82
83 u32 tmp_map[NR_CPUS] = { [0 ... NR_CPUS-1] = MPIDR_INVALID };
84 bool bootcpu_valid = false;
85 cpus = of_find_node_by_path("/cpus");
86
87 if (!cpus)
88 return;
89
90 for_each_child_of_node(cpus, cpu) {
91 const __be32 *cell;
92 int prop_bytes;
93 u32 hwid;
94
95 if (of_node_cmp(cpu->type, "cpu"))
96 continue;
97
98 pr_debug(" * %s...\n", cpu->full_name);
99 /*
100 * A device tree containing CPU nodes with missing "reg"
101 * properties is considered invalid to build the
102 * cpu_logical_map.
103 */
104 cell = of_get_property(cpu, "reg", &prop_bytes);
105 if (!cell || prop_bytes < sizeof(*cell)) {
106 pr_debug(" * %s missing reg property\n",
107 cpu->full_name);
108 of_node_put(cpu);
109 return;
110 }
111
112 /*
113 * Bits n:24 must be set to 0 in the DT since the reg property
114 * defines the MPIDR[23:0].
115 */
116 do {
117 hwid = be32_to_cpu(*cell++);
118 prop_bytes -= sizeof(*cell);
119 } while (!hwid && prop_bytes > 0);
120
121 if (prop_bytes || (hwid & ~MPIDR_HWID_BITMASK)) {
122 of_node_put(cpu);
123 return;
124 }
125
126 /*
127 * Duplicate MPIDRs are a recipe for disaster.
128 * Scan all initialized entries and check for
129 * duplicates. If any is found just bail out.
130 * temp values were initialized to UINT_MAX
131 * to avoid matching valid MPIDR[23:0] values.
132 */
133 for (j = 0; j < cpuidx; j++)
134 if (WARN(tmp_map[j] == hwid,
135 "Duplicate /cpu reg properties in the DT\n")) {
136 of_node_put(cpu);
137 return;
138 }
139
140 /*
141 * Build a stashed array of MPIDR values. Numbering scheme
142 * requires that if detected the boot CPU must be assigned
143 * logical id 0. Other CPUs get sequential indexes starting
144 * from 1. If a CPU node with a reg property matching the
145 * boot CPU MPIDR is detected, this is recorded so that the
146 * logical map built from DT is validated and can be used
147 * to override the map created in smp_setup_processor_id().
148 */
149 if (hwid == mpidr) {
150 i = 0;
151 bootcpu_valid = true;
152 } else {
153 i = cpuidx++;
154 }
155
156 if (WARN(cpuidx > nr_cpu_ids, "DT /cpu %u nodes greater than "
157 "max cores %u, capping them\n",
158 cpuidx, nr_cpu_ids)) {
159 cpuidx = nr_cpu_ids;
160 of_node_put(cpu);
161 break;
162 }
163
164 tmp_map[i] = hwid;
165
166 if (!found_method)
167 found_method = set_smp_ops_by_method(cpu);
168 }
169
170 /*
171 * Fallback to an enable-method in the cpus node if nothing found in
172 * a cpu node.
173 */
174 if (!found_method)
175 set_smp_ops_by_method(cpus);
176
177 if (!bootcpu_valid) {
178 pr_warn("DT missing boot CPU MPIDR[23:0], fall back to default cpu_logical_map\n");
179 return;
180 }
181
182 /*
183 * Since the boot CPU node contains proper data, and all nodes have
184 * a reg property, the DT CPU list can be considered valid and the
185 * logical map created in smp_setup_processor_id() can be overridden
186 */
187 for (i = 0; i < cpuidx; i++) {
188 set_cpu_possible(i, true);
189 cpu_logical_map(i) = tmp_map[i];
190 pr_debug("cpu logical map 0x%x\n", cpu_logical_map(i));
191 }
192}
193
194bool arch_match_cpu_phys_id(int cpu, u64 phys_id)
195{
196 return phys_id == cpu_logical_map(cpu);
197}
198
199static const void * __init arch_get_next_mach(const char *const **match)
200{
201 static const struct machine_desc *mdesc = __arch_info_begin;
202 const struct machine_desc *m = mdesc;
203
204 if (m >= __arch_info_end)
205 return NULL;
206
207 mdesc++;
208 *match = m->dt_compat;
209 return m;
210}
211
212/**
213 * setup_machine_fdt - Machine setup when an dtb was passed to the kernel
214 * @dt_phys: physical address of dt blob
215 *
216 * If a dtb was passed to the kernel in r2, then use it to choose the
217 * correct machine_desc and to setup the system.
218 */
219const struct machine_desc * __init setup_machine_fdt(unsigned int dt_phys)
220{
221 const struct machine_desc *mdesc, *mdesc_best = NULL;
222
223#if defined(CONFIG_ARCH_MULTIPLATFORM) || defined(CONFIG_ARM_SINGLE_ARMV7M)
224 DT_MACHINE_START(GENERIC_DT, "Generic DT based system")
225 .l2c_aux_val = 0x0,
226 .l2c_aux_mask = ~0x0,
227 MACHINE_END
228
229 mdesc_best = &__mach_desc_GENERIC_DT;
230#endif
231
232 if (!dt_phys || !early_init_dt_verify(phys_to_virt(dt_phys)))
233 return NULL;
234
235 mdesc = of_flat_dt_match_machine(mdesc_best, arch_get_next_mach);
236
237 if (!mdesc) {
238 const char *prop;
239 int size;
240 unsigned long dt_root;
241
242 early_print("\nError: unrecognized/unsupported "
243 "device tree compatible list:\n[ ");
244
245 dt_root = of_get_flat_dt_root();
246 prop = of_get_flat_dt_prop(dt_root, "compatible", &size);
247 while (size > 0) {
248 early_print("'%s' ", prop);
249 size -= strlen(prop) + 1;
250 prop += strlen(prop) + 1;
251 }
252 early_print("]\n\n");
253
254 dump_machine_table(); /* does not return */
255 }
256
257 /* We really don't want to do this, but sometimes firmware provides buggy data */
258 if (mdesc->dt_fixup)
259 mdesc->dt_fixup();
260
261 early_init_dt_scan_nodes();
262
263 /* Change machine number to match the mdesc we're using */
264 __machine_arch_type = mdesc->nr;
265
266 return mdesc;
267}
1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * linux/arch/arm/kernel/devtree.c
4 *
5 * Copyright (C) 2009 Canonical Ltd. <jeremy.kerr@canonical.com>
6 */
7
8#include <linux/init.h>
9#include <linux/export.h>
10#include <linux/errno.h>
11#include <linux/types.h>
12#include <linux/memblock.h>
13#include <linux/of.h>
14#include <linux/of_fdt.h>
15#include <linux/of_irq.h>
16#include <linux/of_platform.h>
17#include <linux/smp.h>
18
19#include <asm/cputype.h>
20#include <asm/setup.h>
21#include <asm/page.h>
22#include <asm/prom.h>
23#include <asm/smp_plat.h>
24#include <asm/mach/arch.h>
25#include <asm/mach-types.h>
26
27
28#ifdef CONFIG_SMP
29extern struct of_cpu_method __cpu_method_of_table[];
30
31static const struct of_cpu_method __cpu_method_of_table_sentinel
32 __used __section(__cpu_method_of_table_end);
33
34
35static int __init set_smp_ops_by_method(struct device_node *node)
36{
37 const char *method;
38 struct of_cpu_method *m = __cpu_method_of_table;
39
40 if (of_property_read_string(node, "enable-method", &method))
41 return 0;
42
43 for (; m->method; m++)
44 if (!strcmp(m->method, method)) {
45 smp_set_ops(m->ops);
46 return 1;
47 }
48
49 return 0;
50}
51#else
52static inline int set_smp_ops_by_method(struct device_node *node)
53{
54 return 1;
55}
56#endif
57
58
59/*
60 * arm_dt_init_cpu_maps - Function retrieves cpu nodes from the device tree
61 * and builds the cpu logical map array containing MPIDR values related to
62 * logical cpus
63 *
64 * Updates the cpu possible mask with the number of parsed cpu nodes
65 */
66void __init arm_dt_init_cpu_maps(void)
67{
68 /*
69 * Temp logical map is initialized with UINT_MAX values that are
70 * considered invalid logical map entries since the logical map must
71 * contain a list of MPIDR[23:0] values where MPIDR[31:24] must
72 * read as 0.
73 */
74 struct device_node *cpu, *cpus;
75 int found_method = 0;
76 u32 i, j, cpuidx = 1;
77 u32 mpidr = is_smp() ? read_cpuid_mpidr() & MPIDR_HWID_BITMASK : 0;
78
79 u32 tmp_map[NR_CPUS] = { [0 ... NR_CPUS-1] = MPIDR_INVALID };
80 bool bootcpu_valid = false;
81 cpus = of_find_node_by_path("/cpus");
82
83 if (!cpus)
84 return;
85
86 for_each_of_cpu_node(cpu) {
87 const __be32 *cell;
88 int prop_bytes;
89 u32 hwid;
90
91 pr_debug(" * %pOF...\n", cpu);
92 /*
93 * A device tree containing CPU nodes with missing "reg"
94 * properties is considered invalid to build the
95 * cpu_logical_map.
96 */
97 cell = of_get_property(cpu, "reg", &prop_bytes);
98 if (!cell || prop_bytes < sizeof(*cell)) {
99 pr_debug(" * %pOF missing reg property\n", cpu);
100 of_node_put(cpu);
101 return;
102 }
103
104 /*
105 * Bits n:24 must be set to 0 in the DT since the reg property
106 * defines the MPIDR[23:0].
107 */
108 do {
109 hwid = be32_to_cpu(*cell++);
110 prop_bytes -= sizeof(*cell);
111 } while (!hwid && prop_bytes > 0);
112
113 if (prop_bytes || (hwid & ~MPIDR_HWID_BITMASK)) {
114 of_node_put(cpu);
115 return;
116 }
117
118 /*
119 * Duplicate MPIDRs are a recipe for disaster.
120 * Scan all initialized entries and check for
121 * duplicates. If any is found just bail out.
122 * temp values were initialized to UINT_MAX
123 * to avoid matching valid MPIDR[23:0] values.
124 */
125 for (j = 0; j < cpuidx; j++)
126 if (WARN(tmp_map[j] == hwid,
127 "Duplicate /cpu reg properties in the DT\n")) {
128 of_node_put(cpu);
129 return;
130 }
131
132 /*
133 * Build a stashed array of MPIDR values. Numbering scheme
134 * requires that if detected the boot CPU must be assigned
135 * logical id 0. Other CPUs get sequential indexes starting
136 * from 1. If a CPU node with a reg property matching the
137 * boot CPU MPIDR is detected, this is recorded so that the
138 * logical map built from DT is validated and can be used
139 * to override the map created in smp_setup_processor_id().
140 */
141 if (hwid == mpidr) {
142 i = 0;
143 bootcpu_valid = true;
144 } else {
145 i = cpuidx++;
146 }
147
148 if (WARN(cpuidx > nr_cpu_ids, "DT /cpu %u nodes greater than "
149 "max cores %u, capping them\n",
150 cpuidx, nr_cpu_ids)) {
151 cpuidx = nr_cpu_ids;
152 of_node_put(cpu);
153 break;
154 }
155
156 tmp_map[i] = hwid;
157
158 if (!found_method)
159 found_method = set_smp_ops_by_method(cpu);
160 }
161
162 /*
163 * Fallback to an enable-method in the cpus node if nothing found in
164 * a cpu node.
165 */
166 if (!found_method)
167 set_smp_ops_by_method(cpus);
168
169 if (!bootcpu_valid) {
170 pr_warn("DT missing boot CPU MPIDR[23:0], fall back to default cpu_logical_map\n");
171 return;
172 }
173
174 /*
175 * Since the boot CPU node contains proper data, and all nodes have
176 * a reg property, the DT CPU list can be considered valid and the
177 * logical map created in smp_setup_processor_id() can be overridden
178 */
179 for (i = 0; i < cpuidx; i++) {
180 set_cpu_possible(i, true);
181 cpu_logical_map(i) = tmp_map[i];
182 pr_debug("cpu logical map 0x%x\n", cpu_logical_map(i));
183 }
184}
185
186bool arch_match_cpu_phys_id(int cpu, u64 phys_id)
187{
188 return phys_id == cpu_logical_map(cpu);
189}
190
191static const void * __init arch_get_next_mach(const char *const **match)
192{
193 static const struct machine_desc *mdesc = __arch_info_begin;
194 const struct machine_desc *m = mdesc;
195
196 if (m >= __arch_info_end)
197 return NULL;
198
199 mdesc++;
200 *match = m->dt_compat;
201 return m;
202}
203
204/**
205 * setup_machine_fdt - Machine setup when an dtb was passed to the kernel
206 * @dt_phys: physical address of dt blob
207 *
208 * If a dtb was passed to the kernel in r2, then use it to choose the
209 * correct machine_desc and to setup the system.
210 */
211const struct machine_desc * __init setup_machine_fdt(unsigned int dt_phys)
212{
213 const struct machine_desc *mdesc, *mdesc_best = NULL;
214
215#if defined(CONFIG_ARCH_MULTIPLATFORM) || defined(CONFIG_ARM_SINGLE_ARMV7M)
216 DT_MACHINE_START(GENERIC_DT, "Generic DT based system")
217 .l2c_aux_val = 0x0,
218 .l2c_aux_mask = ~0x0,
219 MACHINE_END
220
221 mdesc_best = &__mach_desc_GENERIC_DT;
222#endif
223
224 if (!dt_phys || !early_init_dt_verify(phys_to_virt(dt_phys)))
225 return NULL;
226
227 mdesc = of_flat_dt_match_machine(mdesc_best, arch_get_next_mach);
228
229 if (!mdesc) {
230 const char *prop;
231 int size;
232 unsigned long dt_root;
233
234 early_print("\nError: unrecognized/unsupported "
235 "device tree compatible list:\n[ ");
236
237 dt_root = of_get_flat_dt_root();
238 prop = of_get_flat_dt_prop(dt_root, "compatible", &size);
239 while (size > 0) {
240 early_print("'%s' ", prop);
241 size -= strlen(prop) + 1;
242 prop += strlen(prop) + 1;
243 }
244 early_print("]\n\n");
245
246 dump_machine_table(); /* does not return */
247 }
248
249 /* We really don't want to do this, but sometimes firmware provides buggy data */
250 if (mdesc->dt_fixup)
251 mdesc->dt_fixup();
252
253 early_init_dt_scan_nodes();
254
255 /* Change machine number to match the mdesc we're using */
256 __machine_arch_type = mdesc->nr;
257
258 return mdesc;
259}