xref: /openbmc/linux/arch/mips/kernel/prom.c (revision 95e9fd10)
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 int __init early_init_dt_scan_memory_arch(unsigned long node,
27 					  const char *uname, int depth,
28 					  void *data)
29 {
30 	return early_init_dt_scan_memory(node, uname, depth, data);
31 }
32 
33 void __init early_init_dt_add_memory_arch(u64 base, u64 size)
34 {
35 	return add_memory_region(base, size, BOOT_MEM_RAM);
36 }
37 
38 void * __init early_init_dt_alloc_memory_arch(u64 size, u64 align)
39 {
40 	return __alloc_bootmem(size, align, __pa(MAX_DMA_ADDRESS));
41 }
42 
43 #ifdef CONFIG_BLK_DEV_INITRD
44 void __init early_init_dt_setup_initrd_arch(unsigned long start,
45 					    unsigned long end)
46 {
47 	initrd_start = (unsigned long)__va(start);
48 	initrd_end = (unsigned long)__va(end);
49 	initrd_below_start_ok = 1;
50 }
51 #endif
52 
53 void __init early_init_devtree(void *params)
54 {
55 	/* Setup flat device-tree pointer */
56 	initial_boot_params = params;
57 
58 	/* Retrieve various informations from the /chosen node of the
59 	 * device-tree, including the platform type, initrd location and
60 	 * size, and more ...
61 	 */
62 	of_scan_flat_dt(early_init_dt_scan_chosen, arcs_cmdline);
63 
64 
65 	/* Scan memory nodes */
66 	of_scan_flat_dt(early_init_dt_scan_root, NULL);
67 	of_scan_flat_dt(early_init_dt_scan_memory_arch, NULL);
68 }
69 
70 void __init __dt_setup_arch(struct boot_param_header *bph)
71 {
72 	if (be32_to_cpu(bph->magic) != OF_DT_HEADER) {
73 		pr_err("DTB has bad magic, ignoring builtin OF DTB\n");
74 
75 		return;
76 	}
77 
78 	initial_boot_params = bph;
79 
80 	early_init_devtree(initial_boot_params);
81 }
82