xref: /openbmc/linux/arch/mips/kernel/prom.c (revision f7777dcc)
1 /*
2  * MIPS support for CONFIG_OF device tree support
3  *
4  * Copyright (C) 2010 Cisco Systems Inc. <dediao@cisco.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/initrd.h>
17 #include <linux/debugfs.h>
18 #include <linux/of.h>
19 #include <linux/of_fdt.h>
20 #include <linux/of_irq.h>
21 #include <linux/of_platform.h>
22 
23 #include <asm/page.h>
24 #include <asm/prom.h>
25 
26 static char mips_machine_name[64] = "Unknown";
27 
28 __init void mips_set_machine_name(const char *name)
29 {
30 	if (name == NULL)
31 		return;
32 
33 	strlcpy(mips_machine_name, name, sizeof(mips_machine_name));
34 	pr_info("MIPS: machine is %s\n", mips_get_machine_name());
35 }
36 
37 char *mips_get_machine_name(void)
38 {
39 	return mips_machine_name;
40 }
41 
42 #ifdef CONFIG_OF
43 int __init early_init_dt_scan_memory_arch(unsigned long node,
44 					  const char *uname, int depth,
45 					  void *data)
46 {
47 	return early_init_dt_scan_memory(node, uname, depth, data);
48 }
49 
50 void __init early_init_dt_add_memory_arch(u64 base, u64 size)
51 {
52 	return add_memory_region(base, size, BOOT_MEM_RAM);
53 }
54 
55 void * __init early_init_dt_alloc_memory_arch(u64 size, u64 align)
56 {
57 	return __alloc_bootmem(size, align, __pa(MAX_DMA_ADDRESS));
58 }
59 
60 #ifdef CONFIG_BLK_DEV_INITRD
61 void __init early_init_dt_setup_initrd_arch(u64 start, u64 end)
62 {
63 	initrd_start = (unsigned long)__va(start);
64 	initrd_end = (unsigned long)__va(end);
65 	initrd_below_start_ok = 1;
66 }
67 #endif
68 
69 int __init early_init_dt_scan_model(unsigned long node,	const char *uname,
70 				    int depth, void *data)
71 {
72 	if (!depth) {
73 		char *model = of_get_flat_dt_prop(node, "model", NULL);
74 
75 		if (model)
76 			mips_set_machine_name(model);
77 	}
78 	return 0;
79 }
80 
81 void __init early_init_devtree(void *params)
82 {
83 	/* Setup flat device-tree pointer */
84 	initial_boot_params = params;
85 
86 	/* Retrieve various informations from the /chosen node of the
87 	 * device-tree, including the platform type, initrd location and
88 	 * size, and more ...
89 	 */
90 	of_scan_flat_dt(early_init_dt_scan_chosen, arcs_cmdline);
91 
92 
93 	/* Scan memory nodes */
94 	of_scan_flat_dt(early_init_dt_scan_root, NULL);
95 	of_scan_flat_dt(early_init_dt_scan_memory_arch, NULL);
96 
97 	/* try to load the mips machine name */
98 	of_scan_flat_dt(early_init_dt_scan_model, NULL);
99 }
100 
101 void __init __dt_setup_arch(struct boot_param_header *bph)
102 {
103 	if (be32_to_cpu(bph->magic) != OF_DT_HEADER) {
104 		pr_err("DTB has bad magic, ignoring builtin OF DTB\n");
105 
106 		return;
107 	}
108 
109 	initial_boot_params = bph;
110 
111 	early_init_devtree(initial_boot_params);
112 }
113 #endif
114