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/export.h>
18#include <linux/kernel.h>
19#include <linux/string.h>
20#include <linux/init.h>
21#include <linux/threads.h>
22#include <linux/spinlock.h>
23#include <linux/types.h>
24#include <linux/pci.h>
25#include <linux/stringify.h>
26#include <linux/delay.h>
27#include <linux/initrd.h>
28#include <linux/bitops.h>
29#include <linux/kexec.h>
30#include <linux/debugfs.h>
31#include <linux/irq.h>
32#include <linux/memblock.h>
33#include <linux/of_fdt.h>
34
35#include <asm/prom.h>
36#include <asm/page.h>
37#include <asm/processor.h>
38#include <asm/irq.h>
39#include <linux/io.h>
40#include <asm/mmu.h>
41#include <asm/pgtable.h>
42#include <asm/sections.h>
43#include <asm/pci-bridge.h>
44
45#ifdef CONFIG_EARLY_PRINTK
46static const char *stdout;
47
48static int __init early_init_dt_scan_chosen_serial(unsigned long node,
49				const char *uname, int depth, void *data)
50{
51	int l;
52	const char *p;
53
54	pr_debug("%s: depth: %d, uname: %s\n", __func__, depth, uname);
55
56	if (depth == 1 && (strcmp(uname, "chosen") == 0 ||
57				strcmp(uname, "chosen@0") == 0)) {
58		p = of_get_flat_dt_prop(node, "linux,stdout-path", &l);
59		if (p != NULL && l > 0)
60			stdout = p; /* store pointer to stdout-path */
61	}
62
63	if (stdout && strstr(stdout, uname)) {
64		p = of_get_flat_dt_prop(node, "compatible", &l);
65		pr_debug("Compatible string: %s\n", p);
66
67		if ((strncmp(p, "xlnx,xps-uart16550", 18) == 0) ||
68			(strncmp(p, "xlnx,axi-uart16550", 18) == 0)) {
69			unsigned int addr;
70
71			*(u32 *)data = UART16550;
72
73			addr = *(u32 *)of_get_flat_dt_prop(node, "reg", &l);
74			addr += *(u32 *)of_get_flat_dt_prop(node,
75							"reg-offset", &l);
76			/* clear register offset */
77			return be32_to_cpu(addr) & ~3;
78		}
79		if ((strncmp(p, "xlnx,xps-uartlite", 17) == 0) ||
80				(strncmp(p, "xlnx,opb-uartlite", 17) == 0) ||
81				(strncmp(p, "xlnx,axi-uartlite", 17) == 0) ||
82				(strncmp(p, "xlnx,mdm", 8) == 0)) {
83			const unsigned int *addrp;
84
85			*(u32 *)data = UARTLITE;
86
87			addrp = of_get_flat_dt_prop(node, "reg", &l);
88			return be32_to_cpup(addrp); /* return address */
89		}
90	}
91	return 0;
92}
93
94/* this function is looking for early console - Microblaze specific */
95int __init of_early_console(void *version)
96{
97	return of_scan_flat_dt(early_init_dt_scan_chosen_serial, version);
98}
99#endif
100
101void __init early_init_devtree(void *params)
102{
103	pr_debug(" -> early_init_devtree(%p)\n", params);
104
105	early_init_dt_scan(params);
106	if (!strlen(boot_command_line))
107		strlcpy(boot_command_line, cmd_line, COMMAND_LINE_SIZE);
108
109	parse_early_param();
110
111	memblock_allow_resize();
112
113	pr_debug("Phys. mem: %lx\n", (unsigned long) memblock_phys_mem_size());
114
115	pr_debug(" <- early_init_devtree()\n");
116}
117