xref: /openbmc/linux/arch/microblaze/kernel/prom.c (revision baa7eb025ab14f3cba2e35c0a8648f9c9f01d24f)
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_add_memory_arch(u64 base, u64 size)
46 {
47 	memblock_add(base, size);
48 }
49 
50 u64 __init early_init_dt_alloc_memory_arch(u64 size, u64 align)
51 {
52 	return memblock_alloc(size, align);
53 }
54 
55 #ifdef CONFIG_EARLY_PRINTK
56 /* MS this is Microblaze specifig function */
57 static int __init early_init_dt_scan_serial(unsigned long node,
58 				const char *uname, int depth, void *data)
59 {
60 	unsigned long l;
61 	char *p;
62 	int *addr;
63 
64 	pr_debug("search \"chosen\", depth: %d, uname: %s\n", depth, uname);
65 
66 /* find all serial nodes */
67 	if (strncmp(uname, "serial", 6) != 0)
68 		return 0;
69 
70 	early_init_dt_check_for_initrd(node);
71 
72 /* find compatible node with uartlite */
73 	p = of_get_flat_dt_prop(node, "compatible", &l);
74 	if ((strncmp(p, "xlnx,xps-uartlite", 17) != 0) &&
75 			(strncmp(p, "xlnx,opb-uartlite", 17) != 0) &&
76 			(strncmp(p, "xlnx,axi-uartlite", 17) != 0))
77 		return 0;
78 
79 	addr = of_get_flat_dt_prop(node, "reg", &l);
80 	return be32_to_cpup(addr); /* return address */
81 }
82 
83 /* this function is looking for early uartlite console - Microblaze specific */
84 int __init early_uartlite_console(void)
85 {
86 	return of_scan_flat_dt(early_init_dt_scan_serial, NULL);
87 }
88 
89 /* MS this is Microblaze specifig function */
90 static int __init early_init_dt_scan_serial_full(unsigned long node,
91 				const char *uname, int depth, void *data)
92 {
93 	unsigned long l;
94 	char *p;
95 	unsigned int addr;
96 
97 	pr_debug("search \"chosen\", depth: %d, uname: %s\n", depth, uname);
98 
99 /* find all serial nodes */
100 	if (strncmp(uname, "serial", 6) != 0)
101 		return 0;
102 
103 	early_init_dt_check_for_initrd(node);
104 
105 /* find compatible node with uartlite */
106 	p = of_get_flat_dt_prop(node, "compatible", &l);
107 
108 	if ((strncmp(p, "xlnx,xps-uart16550", 18) != 0) &&
109 		(strncmp(p, "xlnx,axi-uart16550", 18) != 0))
110 		return 0;
111 
112 	addr = *(u32 *)of_get_flat_dt_prop(node, "reg", &l);
113 	addr += *(u32 *)of_get_flat_dt_prop(node, "reg-offset", &l);
114 	return be32_to_cpu(addr); /* return address */
115 }
116 
117 /* this function is looking for early uartlite console - Microblaze specific */
118 int __init early_uart16550_console(void)
119 {
120 	return of_scan_flat_dt(early_init_dt_scan_serial_full, NULL);
121 }
122 #endif
123 
124 void __init early_init_devtree(void *params)
125 {
126 	pr_debug(" -> early_init_devtree(%p)\n", params);
127 
128 	/* Setup flat device-tree pointer */
129 	initial_boot_params = params;
130 
131 	/* Retrieve various informations from the /chosen node of the
132 	 * device-tree, including the platform type, initrd location and
133 	 * size, TCE reserve, and more ...
134 	 */
135 	of_scan_flat_dt(early_init_dt_scan_chosen, NULL);
136 
137 	/* Scan memory nodes and rebuild MEMBLOCKs */
138 	memblock_init();
139 	of_scan_flat_dt(early_init_dt_scan_root, NULL);
140 	of_scan_flat_dt(early_init_dt_scan_memory, NULL);
141 
142 	/* Save command line for /proc/cmdline and then parse parameters */
143 	strlcpy(boot_command_line, cmd_line, COMMAND_LINE_SIZE);
144 	parse_early_param();
145 
146 	memblock_analyze();
147 
148 	pr_debug("Phys. mem: %lx\n", (unsigned long) memblock_phys_mem_size());
149 
150 	pr_debug(" <- early_init_devtree()\n");
151 }
152 
153 #ifdef CONFIG_BLK_DEV_INITRD
154 void __init early_init_dt_setup_initrd_arch(unsigned long start,
155 		unsigned long end)
156 {
157 	initrd_start = (unsigned long)__va(start);
158 	initrd_end = (unsigned long)__va(end);
159 	initrd_below_start_ok = 1;
160 }
161 #endif
162 
163 /*******
164  *
165  * New implementation of the OF "find" APIs, return a refcounted
166  * object, call of_node_put() when done.  The device tree and list
167  * are protected by a rw_lock.
168  *
169  * Note that property management will need some locking as well,
170  * this isn't dealt with yet.
171  *
172  *******/
173 
174 #if defined(CONFIG_DEBUG_FS) && defined(DEBUG)
175 static struct debugfs_blob_wrapper flat_dt_blob;
176 
177 static int __init export_flat_device_tree(void)
178 {
179 	struct dentry *d;
180 
181 	flat_dt_blob.data = initial_boot_params;
182 	flat_dt_blob.size = initial_boot_params->totalsize;
183 
184 	d = debugfs_create_blob("flat-device-tree", S_IFREG | S_IRUSR,
185 				of_debugfs_root, &flat_dt_blob);
186 	if (!d)
187 		return 1;
188 
189 	return 0;
190 }
191 device_initcall(export_flat_device_tree);
192 #endif
193