diff options
Diffstat (limited to 'arch/arm/kernel/devtree.c')
-rw-r--r-- | arch/arm/kernel/devtree.c | 145 |
1 files changed, 145 insertions, 0 deletions
diff --git a/arch/arm/kernel/devtree.c b/arch/arm/kernel/devtree.c new file mode 100644 index 00000000000..a701e4226a6 --- /dev/null +++ b/arch/arm/kernel/devtree.c | |||
@@ -0,0 +1,145 @@ | |||
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 | |||
27 | void __init early_init_dt_add_memory_arch(u64 base, u64 size) | ||
28 | { | ||
29 | arm_add_memory(base, size); | ||
30 | } | ||
31 | |||
32 | void * __init early_init_dt_alloc_memory_arch(u64 size, u64 align) | ||
33 | { | ||
34 | return alloc_bootmem_align(size, align); | ||
35 | } | ||
36 | |||
37 | void __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 | */ | ||
71 | struct 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 | devtree = phys_to_virt(dt_phys); | ||
80 | |||
81 | /* check device tree validity */ | ||
82 | if (be32_to_cpu(devtree->magic) != OF_DT_HEADER) | ||
83 | return NULL; | ||
84 | |||
85 | /* Search the mdescs for the 'best' compatible value match */ | ||
86 | initial_boot_params = devtree; | ||
87 | dt_root = of_get_flat_dt_root(); | ||
88 | for_each_machine_desc(mdesc) { | ||
89 | score = of_flat_dt_match(dt_root, mdesc->dt_compat); | ||
90 | if (score > 0 && score < mdesc_score) { | ||
91 | mdesc_best = mdesc; | ||
92 | mdesc_score = score; | ||
93 | } | ||
94 | } | ||
95 | if (!mdesc_best) { | ||
96 | const char *prop; | ||
97 | long size; | ||
98 | |||
99 | early_print("\nError: unrecognized/unsupported " | ||
100 | "device tree compatible list:\n[ "); | ||
101 | |||
102 | prop = of_get_flat_dt_prop(dt_root, "compatible", &size); | ||
103 | while (size > 0) { | ||
104 | early_print("'%s' ", prop); | ||
105 | size -= strlen(prop) + 1; | ||
106 | prop += strlen(prop) + 1; | ||
107 | } | ||
108 | early_print("]\n\n"); | ||
109 | |||
110 | dump_machine_table(); /* does not return */ | ||
111 | } | ||
112 | |||
113 | model = of_get_flat_dt_prop(dt_root, "model", NULL); | ||
114 | if (!model) | ||
115 | model = of_get_flat_dt_prop(dt_root, "compatible", NULL); | ||
116 | if (!model) | ||
117 | model = "<unknown>"; | ||
118 | pr_info("Machine: %s, model: %s\n", mdesc_best->name, model); | ||
119 | |||
120 | /* Retrieve various information from the /chosen node */ | ||
121 | of_scan_flat_dt(early_init_dt_scan_chosen, boot_command_line); | ||
122 | /* Initialize {size,address}-cells info */ | ||
123 | of_scan_flat_dt(early_init_dt_scan_root, NULL); | ||
124 | /* Setup memory, calling early_init_dt_add_memory_arch */ | ||
125 | of_scan_flat_dt(early_init_dt_scan_memory, NULL); | ||
126 | |||
127 | /* Change machine number to match the mdesc we're using */ | ||
128 | __machine_arch_type = mdesc_best->nr; | ||
129 | |||
130 | return mdesc_best; | ||
131 | } | ||
132 | |||
133 | /** | ||
134 | * irq_create_of_mapping - Hook to resolve OF irq specifier into a Linux irq# | ||
135 | * | ||
136 | * Currently the mapping mechanism is trivial; simple flat hwirq numbers are | ||
137 | * mapped 1:1 onto Linux irq numbers. Cascaded irq controllers are not | ||
138 | * supported. | ||
139 | */ | ||
140 | unsigned int irq_create_of_mapping(struct device_node *controller, | ||
141 | const u32 *intspec, unsigned int intsize) | ||
142 | { | ||
143 | return intspec[0]; | ||
144 | } | ||
145 | EXPORT_SYMBOL_GPL(irq_create_of_mapping); | ||