1/*
2 *  Ralink SoC specific prom routines
3 *
4 *  Copyright (C) 2010 Joonas Lahtinen <joonas.lahtinen@gmail.com>
5 *  Copyright (C) 2009 Gabor Juhos <juhosg@openwrt.org>
6 *
7 *  This program is free software; you can redistribute it and/or modify it
8 *  under the terms of the GNU General Public License version 2 as published
9 *  by the Free Software Foundation.
10 */
11
12#include <linux/kernel.h>
13#include <linux/init.h>
14#include <linux/string.h>
15
16#include <asm/bootinfo.h>
17#include <asm/addrspace.h>
18
19#include <asm/mach-ralink/common.h>
20#include <asm/mach-ralink/machine.h>
21
22unsigned long ramips_mem_base;
23unsigned long ramips_mem_size_min;
24unsigned long ramips_mem_size_max;
25
26static inline void *to_ram_addr(void *addr)
27{
28	u32 base;
29
30	base = KSEG0ADDR(ramips_mem_base);
31	if (((u32) addr > base) &&
32	    ((u32) addr < (base + ramips_mem_size_max)))
33		return addr;
34
35	base = KSEG1ADDR(ramips_mem_base);
36	if (((u32) addr > base) &&
37	    ((u32) addr < (base + ramips_mem_size_max)))
38		return addr;
39
40	/* some U-Boot variants uses physical addresses */
41	base = ramips_mem_base;
42	if (((u32) addr > base) &&
43	    ((u32) addr < (base + ramips_mem_size_max)))
44		return (void *)KSEG0ADDR(addr);
45
46	return NULL;
47}
48
49static char ramips_cmdline_buf[COMMAND_LINE_SIZE] __initdata;
50static void __init prom_append_cmdline(const char *name,
51				       const char *value)
52{
53	snprintf(ramips_cmdline_buf, sizeof(ramips_cmdline_buf),
54		 " %s=%s", name, value);
55	strlcat(arcs_cmdline, ramips_cmdline_buf, sizeof(arcs_cmdline));
56}
57
58#ifdef CONFIG_IMAGE_CMDLINE_HACK
59extern char __image_cmdline[];
60
61static int __init use_image_cmdline(void)
62{
63	char *p = __image_cmdline;
64	int replace = 0;
65
66	if (*p == '-') {
67		replace = 1;
68		p++;
69	}
70
71	if (*p == '\0')
72		return 0;
73
74	if (replace) {
75		strlcpy(arcs_cmdline, p, sizeof(arcs_cmdline));
76	} else {
77		strlcat(arcs_cmdline, " ", sizeof(arcs_cmdline));
78		strlcat(arcs_cmdline, p, sizeof(arcs_cmdline));
79	}
80
81	return 1;
82}
83#else
84static int inline use_image_cmdline(void) { return 0; }
85#endif
86
87static __init void prom_init_cmdline(int argc, char **argv)
88{
89	int i;
90
91	if (use_image_cmdline())
92		return;
93
94	if (!argv) {
95		printk(KERN_DEBUG "argv=%p is invalid, skipping\n",
96		       argv);
97		return;
98	}
99
100	for (i = 0; i < argc; i++) {
101		char *p = to_ram_addr(argv[i]);
102
103		if (!p) {
104			printk(KERN_DEBUG
105			       "argv[%d]=%p is invalid, skipping\n",
106			       i, argv[i]);
107			continue;
108		}
109
110		printk(KERN_DEBUG "argv[%d]: %s\n", i, p);
111		strlcat(arcs_cmdline, " ", sizeof(arcs_cmdline));
112		strlcat(arcs_cmdline, p, sizeof(arcs_cmdline));
113	}
114}
115
116static __init char *prom_append_env(char **env, const char *envname)
117{
118#define PROM_MAX_ENVS	256
119	int len = strlen(envname);
120	int i;
121
122	if (!env) {
123		printk(KERN_DEBUG "env=%p is not in RAM, skipping\n",
124		       env);
125		return NULL;
126	}
127
128	for (i = 0; i < PROM_MAX_ENVS; i++) {
129		char *p = to_ram_addr(env[i]);
130
131		if (!p)
132			break;
133
134		printk(KERN_DEBUG "env[%d]: %s\n", i, p);
135		if (strncmp(envname, p, len) == 0 && p[len] == '=')
136			prom_append_cmdline(envname, p + len + 1);
137	}
138
139	return NULL;
140#undef PROM_MAX_ENVS
141}
142
143void __init prom_init(void)
144{
145	int argc;
146	char **envp;
147	char **argv;
148
149	ramips_soc_prom_init();
150
151	printk(KERN_DEBUG
152	       "prom: fw_arg0=%08x, fw_arg1=%08x, fw_arg2=%08x, fw_arg3=%08x\n",
153	       (unsigned int)fw_arg0, (unsigned int)fw_arg1,
154	       (unsigned int)fw_arg2, (unsigned int)fw_arg3);
155
156	argc = fw_arg0;
157	argv = to_ram_addr((void *)fw_arg1);
158	prom_init_cmdline(argc, argv);
159
160	envp = to_ram_addr((void *)fw_arg2);
161	prom_append_env(envp, "board");
162	prom_append_env(envp, "ethaddr");
163}
164
165void __init prom_free_prom_memory(void)
166{
167	/* We do not have to prom memory to free */
168}
169