xref: /openbmc/linux/arch/microblaze/kernel/prom.c (revision 95f72d1ed41a66f1c1c29c24d479de81a0bea36f)
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/memblock.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 void __init early_init_dt_scan_chosen_arch(unsigned long node)
46 {
47 	/* No Microblaze specific code here */
48 }
49 
50 void __init early_init_dt_add_memory_arch(u64 base, u64 size)
51 {
52 	memblock_add(base, size);
53 }
54 
55 u64 __init early_init_dt_alloc_memory_arch(u64 size, u64 align)
56 {
57 	return memblock_alloc(size, align);
58 }
59 
60 #ifdef CONFIG_EARLY_PRINTK
61 /* MS this is Microblaze specifig function */
62 static int __init early_init_dt_scan_serial(unsigned long node,
63 				const char *uname, int depth, void *data)
64 {
65 	unsigned long l;
66 	char *p;
67 	int *addr;
68 
69 	pr_debug("search \"chosen\", depth: %d, uname: %s\n", depth, uname);
70 
71 /* find all serial nodes */
72 	if (strncmp(uname, "serial", 6) != 0)
73 		return 0;
74 
75 	early_init_dt_check_for_initrd(node);
76 
77 /* find compatible node with uartlite */
78 	p = of_get_flat_dt_prop(node, "compatible", &l);
79 	if ((strncmp(p, "xlnx,xps-uartlite", 17) != 0) &&
80 			(strncmp(p, "xlnx,opb-uartlite", 17) != 0))
81 		return 0;
82 
83 	addr = of_get_flat_dt_prop(node, "reg", &l);
84 	return *addr; /* return address */
85 }
86 
87 /* this function is looking for early uartlite console - Microblaze specific */
88 int __init early_uartlite_console(void)
89 {
90 	return of_scan_flat_dt(early_init_dt_scan_serial, NULL);
91 }
92 #endif
93 
94 void __init early_init_devtree(void *params)
95 {
96 	pr_debug(" -> early_init_devtree(%p)\n", params);
97 
98 	/* Setup flat device-tree pointer */
99 	initial_boot_params = params;
100 
101 	/* Retrieve various informations from the /chosen node of the
102 	 * device-tree, including the platform type, initrd location and
103 	 * size, TCE reserve, and more ...
104 	 */
105 	of_scan_flat_dt(early_init_dt_scan_chosen, NULL);
106 
107 	/* Scan memory nodes and rebuild MEMBLOCKs */
108 	memblock_init();
109 	of_scan_flat_dt(early_init_dt_scan_root, NULL);
110 	of_scan_flat_dt(early_init_dt_scan_memory, NULL);
111 
112 	/* Save command line for /proc/cmdline and then parse parameters */
113 	strlcpy(boot_command_line, cmd_line, COMMAND_LINE_SIZE);
114 	parse_early_param();
115 
116 	memblock_analyze();
117 
118 	pr_debug("Phys. mem: %lx\n", (unsigned long) memblock_phys_mem_size());
119 
120 	pr_debug(" <- early_init_devtree()\n");
121 }
122 
123 #ifdef CONFIG_BLK_DEV_INITRD
124 void __init early_init_dt_setup_initrd_arch(unsigned long start,
125 		unsigned long end)
126 {
127 	initrd_start = (unsigned long)__va(start);
128 	initrd_end = (unsigned long)__va(end);
129 	initrd_below_start_ok = 1;
130 }
131 #endif
132 
133 /*******
134  *
135  * New implementation of the OF "find" APIs, return a refcounted
136  * object, call of_node_put() when done.  The device tree and list
137  * are protected by a rw_lock.
138  *
139  * Note that property management will need some locking as well,
140  * this isn't dealt with yet.
141  *
142  *******/
143 
144 #if defined(CONFIG_DEBUG_FS) && defined(DEBUG)
145 static struct debugfs_blob_wrapper flat_dt_blob;
146 
147 static int __init export_flat_device_tree(void)
148 {
149 	struct dentry *d;
150 
151 	flat_dt_blob.data = initial_boot_params;
152 	flat_dt_blob.size = initial_boot_params->totalsize;
153 
154 	d = debugfs_create_blob("flat-device-tree", S_IFREG | S_IRUSR,
155 				of_debugfs_root, &flat_dt_blob);
156 	if (!d)
157 		return 1;
158 
159 	return 0;
160 }
161 device_initcall(export_flat_device_tree);
162 #endif
163