xref: /openbmc/linux/arch/microblaze/kernel/prom.c (revision 4ef7b373df330bc0ff037dc4792d373c9346375f)
1 /*
2  * Procedures for creating, accessing and interpreting the device tree.
3  *
4  * Paul Mackerras	August 1996.
5  * Copyright (C) 1996-2005 Paul Mackerras.
6  *
7  *  Adapted for 64bit PowerPC by Dave Engebretsen and Peter Bergner.
8  *    {engebret|bergner}@us.ibm.com
9  *
10  *      This program is free software; you can redistribute it and/or
11  *      modify it under the terms of the GNU General Public License
12  *      as published by the Free Software Foundation; either version
13  *      2 of the License, or (at your option) any later version.
14  */
15 
16 #include <stdarg.h>
17 #include <linux/kernel.h>
18 #include <linux/string.h>
19 #include <linux/init.h>
20 #include <linux/threads.h>
21 #include <linux/spinlock.h>
22 #include <linux/types.h>
23 #include <linux/pci.h>
24 #include <linux/stringify.h>
25 #include <linux/delay.h>
26 #include <linux/initrd.h>
27 #include <linux/bitops.h>
28 #include <linux/module.h>
29 #include <linux/kexec.h>
30 #include <linux/debugfs.h>
31 #include <linux/irq.h>
32 #include <linux/lmb.h>
33 
34 #include <asm/prom.h>
35 #include <asm/page.h>
36 #include <asm/processor.h>
37 #include <asm/irq.h>
38 #include <linux/io.h>
39 #include <asm/system.h>
40 #include <asm/mmu.h>
41 #include <asm/pgtable.h>
42 #include <asm/sections.h>
43 #include <asm/pci-bridge.h>
44 
45 /* export that to outside world */
46 struct device_node *of_chosen;
47 
48 void __init early_init_dt_scan_chosen_arch(unsigned long node)
49 {
50 	/* No Microblaze specific code here */
51 }
52 
53 void __init early_init_dt_add_memory_arch(u64 base, u64 size)
54 {
55 	lmb_add(base, size);
56 }
57 
58 u64 __init early_init_dt_alloc_memory_arch(u64 size, u64 align)
59 {
60 	return lmb_alloc(size, align);
61 }
62 
63 #ifdef CONFIG_EARLY_PRINTK
64 /* MS this is Microblaze specifig function */
65 static int __init early_init_dt_scan_serial(unsigned long node,
66 				const char *uname, int depth, void *data)
67 {
68 	unsigned long l;
69 	char *p;
70 	int *addr;
71 
72 	pr_debug("search \"chosen\", depth: %d, uname: %s\n", depth, uname);
73 
74 /* find all serial nodes */
75 	if (strncmp(uname, "serial", 6) != 0)
76 		return 0;
77 
78 	early_init_dt_check_for_initrd(node);
79 
80 /* find compatible node with uartlite */
81 	p = of_get_flat_dt_prop(node, "compatible", &l);
82 	if ((strncmp(p, "xlnx,xps-uartlite", 17) != 0) &&
83 			(strncmp(p, "xlnx,opb-uartlite", 17) != 0))
84 		return 0;
85 
86 	addr = of_get_flat_dt_prop(node, "reg", &l);
87 	return *addr; /* return address */
88 }
89 
90 /* this function is looking for early uartlite console - Microblaze specific */
91 int __init early_uartlite_console(void)
92 {
93 	return of_scan_flat_dt(early_init_dt_scan_serial, NULL);
94 }
95 #endif
96 
97 void __init early_init_devtree(void *params)
98 {
99 	pr_debug(" -> early_init_devtree(%p)\n", params);
100 
101 	/* Setup flat device-tree pointer */
102 	initial_boot_params = params;
103 
104 	/* Retrieve various informations from the /chosen node of the
105 	 * device-tree, including the platform type, initrd location and
106 	 * size, TCE reserve, and more ...
107 	 */
108 	of_scan_flat_dt(early_init_dt_scan_chosen, NULL);
109 
110 	/* Scan memory nodes and rebuild LMBs */
111 	lmb_init();
112 	of_scan_flat_dt(early_init_dt_scan_root, NULL);
113 	of_scan_flat_dt(early_init_dt_scan_memory, NULL);
114 
115 	/* Save command line for /proc/cmdline and then parse parameters */
116 	strlcpy(boot_command_line, cmd_line, COMMAND_LINE_SIZE);
117 	parse_early_param();
118 
119 	lmb_analyze();
120 
121 	pr_debug("Phys. mem: %lx\n", (unsigned long) lmb_phys_mem_size());
122 
123 	pr_debug(" <- early_init_devtree()\n");
124 }
125 
126 #ifdef CONFIG_BLK_DEV_INITRD
127 void __init early_init_dt_setup_initrd_arch(unsigned long start,
128 		unsigned long end)
129 {
130 	initrd_start = (unsigned long)__va(start);
131 	initrd_end = (unsigned long)__va(end);
132 	initrd_below_start_ok = 1;
133 }
134 #endif
135 
136 /*******
137  *
138  * New implementation of the OF "find" APIs, return a refcounted
139  * object, call of_node_put() when done.  The device tree and list
140  * are protected by a rw_lock.
141  *
142  * Note that property management will need some locking as well,
143  * this isn't dealt with yet.
144  *
145  *******/
146 
147 #if defined(CONFIG_DEBUG_FS) && defined(DEBUG)
148 static struct debugfs_blob_wrapper flat_dt_blob;
149 
150 static int __init export_flat_device_tree(void)
151 {
152 	struct dentry *d;
153 
154 	flat_dt_blob.data = initial_boot_params;
155 	flat_dt_blob.size = initial_boot_params->totalsize;
156 
157 	d = debugfs_create_blob("flat-device-tree", S_IFREG | S_IRUSR,
158 				of_debugfs_root, &flat_dt_blob);
159 	if (!d)
160 		return 1;
161 
162 	return 0;
163 }
164 device_initcall(export_flat_device_tree);
165 #endif
166