x86/efi: Enforce CONFIG_RELOCATABLE for EFI boot stub
[linux/fpc-iii.git] / arch / arm / kernel / devtree.c
blob41960fb0daff2b207d14417894b3b0efac6491f1
1 /*
2 * linux/arch/arm/kernel/devtree.c
4 * Copyright (C) 2009 Canonical Ltd. <jeremy.kerr@canonical.com>
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 */
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>
22 #include <asm/cputype.h>
23 #include <asm/setup.h>
24 #include <asm/page.h>
25 #include <asm/smp_plat.h>
26 #include <asm/mach/arch.h>
27 #include <asm/mach-types.h>
29 void __init early_init_dt_add_memory_arch(u64 base, u64 size)
31 arm_add_memory(base, size);
34 void * __init early_init_dt_alloc_memory_arch(u64 size, u64 align)
36 return alloc_bootmem_align(size, align);
39 void __init arm_dt_memblock_reserve(void)
41 u64 *reserve_map, base, size;
43 if (!initial_boot_params)
44 return;
46 /* Reserve the dtb region */
47 memblock_reserve(virt_to_phys(initial_boot_params),
48 be32_to_cpu(initial_boot_params->totalsize));
51 * Process the reserve map. This will probably overlap the initrd
52 * and dtb locations which are already reserved, but overlaping
53 * doesn't hurt anything
55 reserve_map = ((void*)initial_boot_params) +
56 be32_to_cpu(initial_boot_params->off_mem_rsvmap);
57 while (1) {
58 base = be64_to_cpup(reserve_map++);
59 size = be64_to_cpup(reserve_map++);
60 if (!size)
61 break;
62 memblock_reserve(base, size);
67 * arm_dt_init_cpu_maps - Function retrieves cpu nodes from the device tree
68 * and builds the cpu logical map array containing MPIDR values related to
69 * logical cpus
71 * Updates the cpu possible mask with the number of parsed cpu nodes
73 void __init arm_dt_init_cpu_maps(void)
76 * Temp logical map is initialized with UINT_MAX values that are
77 * considered invalid logical map entries since the logical map must
78 * contain a list of MPIDR[23:0] values where MPIDR[31:24] must
79 * read as 0.
81 struct device_node *cpu, *cpus;
82 u32 i, j, cpuidx = 1;
83 u32 mpidr = is_smp() ? read_cpuid_mpidr() & MPIDR_HWID_BITMASK : 0;
85 u32 tmp_map[NR_CPUS] = { [0 ... NR_CPUS-1] = MPIDR_INVALID };
86 bool bootcpu_valid = false;
87 cpus = of_find_node_by_path("/cpus");
89 if (!cpus)
90 return;
92 for_each_child_of_node(cpus, cpu) {
93 u32 hwid;
95 if (of_node_cmp(cpu->type, "cpu"))
96 continue;
98 pr_debug(" * %s...\n", cpu->full_name);
100 * A device tree containing CPU nodes with missing "reg"
101 * properties is considered invalid to build the
102 * cpu_logical_map.
104 if (of_property_read_u32(cpu, "reg", &hwid)) {
105 pr_debug(" * %s missing reg property\n",
106 cpu->full_name);
107 return;
111 * 8 MSBs must be set to 0 in the DT since the reg property
112 * defines the MPIDR[23:0].
114 if (hwid & ~MPIDR_HWID_BITMASK)
115 return;
118 * Duplicate MPIDRs are a recipe for disaster.
119 * Scan all initialized entries and check for
120 * duplicates. If any is found just bail out.
121 * temp values were initialized to UINT_MAX
122 * to avoid matching valid MPIDR[23:0] values.
124 for (j = 0; j < cpuidx; j++)
125 if (WARN(tmp_map[j] == hwid, "Duplicate /cpu reg "
126 "properties in the DT\n"))
127 return;
130 * Build a stashed array of MPIDR values. Numbering scheme
131 * requires that if detected the boot CPU must be assigned
132 * logical id 0. Other CPUs get sequential indexes starting
133 * from 1. If a CPU node with a reg property matching the
134 * boot CPU MPIDR is detected, this is recorded so that the
135 * logical map built from DT is validated and can be used
136 * to override the map created in smp_setup_processor_id().
138 if (hwid == mpidr) {
139 i = 0;
140 bootcpu_valid = true;
141 } else {
142 i = cpuidx++;
145 if (WARN(cpuidx > nr_cpu_ids, "DT /cpu %u nodes greater than "
146 "max cores %u, capping them\n",
147 cpuidx, nr_cpu_ids)) {
148 cpuidx = nr_cpu_ids;
149 break;
152 tmp_map[i] = hwid;
155 if (!bootcpu_valid) {
156 pr_warn("DT missing boot CPU MPIDR[23:0], fall back to default cpu_logical_map\n");
157 return;
161 * Since the boot CPU node contains proper data, and all nodes have
162 * a reg property, the DT CPU list can be considered valid and the
163 * logical map created in smp_setup_processor_id() can be overridden
165 for (i = 0; i < cpuidx; i++) {
166 set_cpu_possible(i, true);
167 cpu_logical_map(i) = tmp_map[i];
168 pr_debug("cpu logical map 0x%x\n", cpu_logical_map(i));
172 bool arch_match_cpu_phys_id(int cpu, u64 phys_id)
174 return phys_id == cpu_logical_map(cpu);
178 * setup_machine_fdt - Machine setup when an dtb was passed to the kernel
179 * @dt_phys: physical address of dt blob
181 * If a dtb was passed to the kernel in r2, then use it to choose the
182 * correct machine_desc and to setup the system.
184 const struct machine_desc * __init setup_machine_fdt(unsigned int dt_phys)
186 struct boot_param_header *devtree;
187 const struct machine_desc *mdesc, *mdesc_best = NULL;
188 unsigned int score, mdesc_score = ~1;
189 unsigned long dt_root;
190 const char *model;
192 #ifdef CONFIG_ARCH_MULTIPLATFORM
193 DT_MACHINE_START(GENERIC_DT, "Generic DT based system")
194 MACHINE_END
196 mdesc_best = &__mach_desc_GENERIC_DT;
197 #endif
199 if (!dt_phys)
200 return NULL;
202 devtree = phys_to_virt(dt_phys);
204 /* check device tree validity */
205 if (be32_to_cpu(devtree->magic) != OF_DT_HEADER)
206 return NULL;
208 /* Search the mdescs for the 'best' compatible value match */
209 initial_boot_params = devtree;
210 dt_root = of_get_flat_dt_root();
211 for_each_machine_desc(mdesc) {
212 score = of_flat_dt_match(dt_root, mdesc->dt_compat);
213 if (score > 0 && score < mdesc_score) {
214 mdesc_best = mdesc;
215 mdesc_score = score;
218 if (!mdesc_best) {
219 const char *prop;
220 long size;
222 early_print("\nError: unrecognized/unsupported "
223 "device tree compatible list:\n[ ");
225 prop = of_get_flat_dt_prop(dt_root, "compatible", &size);
226 while (size > 0) {
227 early_print("'%s' ", prop);
228 size -= strlen(prop) + 1;
229 prop += strlen(prop) + 1;
231 early_print("]\n\n");
233 dump_machine_table(); /* does not return */
236 model = of_get_flat_dt_prop(dt_root, "model", NULL);
237 if (!model)
238 model = of_get_flat_dt_prop(dt_root, "compatible", NULL);
239 if (!model)
240 model = "<unknown>";
241 pr_info("Machine: %s, model: %s\n", mdesc_best->name, model);
243 /* Retrieve various information from the /chosen node */
244 of_scan_flat_dt(early_init_dt_scan_chosen, boot_command_line);
245 /* Initialize {size,address}-cells info */
246 of_scan_flat_dt(early_init_dt_scan_root, NULL);
247 /* Setup memory, calling early_init_dt_add_memory_arch */
248 of_scan_flat_dt(early_init_dt_scan_memory, NULL);
250 /* Change machine number to match the mdesc we're using */
251 __machine_arch_type = mdesc_best->nr;
253 return mdesc_best;