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
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}
135