xref: /linux/arch/openrisc/kernel/prom.c (revision 0d456bad36d42d16022be045c8a53ddbb59ee478)
1 /*
2  * OpenRISC prom.c
3  *
4  * Linux architectural port borrowing liberally from similar works of
5  * others.  All original copyrights apply as per the original source
6  * declaration.
7  *
8  * Modifications for the OpenRISC architecture:
9  * Copyright (C) 2010-2011 Jonas Bonn <jonas@southpole.se>
10  *
11  *      This program is free software; you can redistribute it and/or
12  *      modify it under the terms of the GNU General Public License
13  *      as published by the Free Software Foundation; either version
14  *      2 of the License, or (at your option) any later version.
15  *
16  * Architecture specific procedures for creating, accessing and
17  * interpreting the device tree.
18  *
19  */
20 
21 #include <stdarg.h>
22 #include <linux/kernel.h>
23 #include <linux/string.h>
24 #include <linux/init.h>
25 #include <linux/threads.h>
26 #include <linux/spinlock.h>
27 #include <linux/types.h>
28 #include <linux/pci.h>
29 #include <linux/stringify.h>
30 #include <linux/delay.h>
31 #include <linux/initrd.h>
32 #include <linux/bitops.h>
33 #include <linux/module.h>
34 #include <linux/kexec.h>
35 #include <linux/debugfs.h>
36 #include <linux/irq.h>
37 #include <linux/memblock.h>
38 #include <linux/of_fdt.h>
39 
40 #include <asm/prom.h>
41 #include <asm/page.h>
42 #include <asm/processor.h>
43 #include <asm/irq.h>
44 #include <linux/io.h>
45 #include <asm/mmu.h>
46 #include <asm/pgtable.h>
47 #include <asm/sections.h>
48 #include <asm/setup.h>
49 
50 extern char cmd_line[COMMAND_LINE_SIZE];
51 
52 void __init early_init_dt_add_memory_arch(u64 base, u64 size)
53 {
54 	size &= PAGE_MASK;
55 	memblock_add(base, size);
56 }
57 
58 void * __init early_init_dt_alloc_memory_arch(u64 size, u64 align)
59 {
60 	return __va(memblock_alloc(size, align));
61 }
62 
63 void __init early_init_devtree(void *params)
64 {
65 	void *alloc;
66 
67 	/* Setup flat device-tree pointer */
68 	initial_boot_params = params;
69 
70 
71 	/* Retrieve various informations from the /chosen node of the
72 	 * device-tree, including the platform type, initrd location and
73 	 * size, TCE reserve, and more ...
74 	 */
75 	of_scan_flat_dt(early_init_dt_scan_chosen, cmd_line);
76 
77 	/* Scan memory nodes and rebuild MEMBLOCKs */
78 	of_scan_flat_dt(early_init_dt_scan_root, NULL);
79 	of_scan_flat_dt(early_init_dt_scan_memory, NULL);
80 
81 	/* Save command line for /proc/cmdline and then parse parameters */
82 	strlcpy(boot_command_line, cmd_line, COMMAND_LINE_SIZE);
83 
84 	memblock_allow_resize();
85 
86 	/* We must copy the flattend device tree from init memory to regular
87 	 * memory because the device tree references the strings in it
88 	 * directly.
89 	 */
90 
91 	alloc = __va(memblock_alloc(initial_boot_params->totalsize, PAGE_SIZE));
92 
93 	memcpy(alloc, initial_boot_params, initial_boot_params->totalsize);
94 
95 	initial_boot_params = alloc;
96 }
97 
98 #ifdef CONFIG_BLK_DEV_INITRD
99 void __init early_init_dt_setup_initrd_arch(unsigned long start,
100 		unsigned long end)
101 {
102 	initrd_start = (unsigned long)__va(start);
103 	initrd_end = (unsigned long)__va(end);
104 	initrd_below_start_ok = 1;
105 }
106 #endif
107