xref: /openbmc/linux/arch/mips/ar7/prom.c (revision 5d331b7f)
1 /*
2  * Carsten Langgaard, carstenl@mips.com
3  * Copyright (C) 1999,2000 MIPS Technologies, Inc.  All rights reserved.
4  *
5  *  This program is free software; you can distribute it and/or modify it
6  *  under the terms of the GNU General Public License (Version 2) as
7  *  published by the Free Software Foundation.
8  *
9  *  This program is distributed in the hope it will be useful, but WITHOUT
10  *  ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11  *  FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
12  *  for more details.
13  *
14  *  You should have received a copy of the GNU General Public License along
15  *  with this program; if not, write to the Free Software Foundation, Inc.,
16  *  59 Temple Place - Suite 330, Boston MA 02111-1307, USA.
17  *
18  * Putting things on the screen/serial line using YAMONs facilities.
19  */
20 #include <linux/init.h>
21 #include <linux/kernel.h>
22 #include <linux/serial_reg.h>
23 #include <linux/spinlock.h>
24 #include <linux/export.h>
25 #include <linux/string.h>
26 #include <linux/io.h>
27 #include <asm/bootinfo.h>
28 #include <asm/setup.h>
29 
30 #include <asm/mach-ar7/ar7.h>
31 #include <asm/mach-ar7/prom.h>
32 
33 #define MAX_ENTRY 80
34 
35 struct env_var {
36 	char	*name;
37 	char	*value;
38 };
39 
40 static struct env_var adam2_env[MAX_ENTRY];
41 
42 char *prom_getenv(const char *name)
43 {
44 	int i;
45 
46 	for (i = 0; (i < MAX_ENTRY) && adam2_env[i].name; i++)
47 		if (!strcmp(name, adam2_env[i].name))
48 			return adam2_env[i].value;
49 
50 	return NULL;
51 }
52 EXPORT_SYMBOL(prom_getenv);
53 
54 static void  __init ar7_init_cmdline(int argc, char *argv[])
55 {
56 	int i;
57 
58 	for (i = 1; i < argc; i++) {
59 		strlcat(arcs_cmdline, argv[i], COMMAND_LINE_SIZE);
60 		if (i < (argc - 1))
61 			strlcat(arcs_cmdline, " ", COMMAND_LINE_SIZE);
62 	}
63 }
64 
65 struct psbl_rec {
66 	u32	psbl_size;
67 	u32	env_base;
68 	u32	env_size;
69 	u32	ffs_base;
70 	u32	ffs_size;
71 };
72 
73 static const char psp_env_version[] __initconst = "TIENV0.8";
74 
75 struct psp_env_chunk {
76 	u8	num;
77 	u8	ctrl;
78 	u16	csum;
79 	u8	len;
80 	char	data[11];
81 } __packed;
82 
83 struct psp_var_map_entry {
84 	u8	num;
85 	char	*value;
86 };
87 
88 static const struct psp_var_map_entry psp_var_map[] = {
89 	{  1,	"cpufrequency" },
90 	{  2,	"memsize" },
91 	{  3,	"flashsize" },
92 	{  4,	"modetty0" },
93 	{  5,	"modetty1" },
94 	{  8,	"maca" },
95 	{  9,	"macb" },
96 	{ 28,	"sysfrequency" },
97 	{ 38,	"mipsfrequency" },
98 };
99 
100 /*
101 
102 Well-known variable (num is looked up in table above for matching variable name)
103 Example: cpufrequency=211968000
104 +----+----+----+----+----+----+----+----+----+----+----+----+----+----+----+---
105 | 01 |CTRL|CHECKSUM | 01 | _2 | _1 | _1 | _9 | _6 | _8 | _0 | _0 | _0 | \0 | FF
106 +----+----+----+----+----+----+----+----+----+----+----+----+----+----+----+---
107 
108 Name=Value pair in a single chunk
109 Example: NAME=VALUE
110 +----+----+----+----+----+----+----+----+----+----+----+----+----+----+----+---
111 | 00 |CTRL|CHECKSUM | 01 | _N | _A | _M | _E | _0 | _V | _A | _L | _U | _E | \0
112 +----+----+----+----+----+----+----+----+----+----+----+----+----+----+----+---
113 
114 Name=Value pair in 2 chunks (len is the number of chunks)
115 Example: bootloaderVersion=1.3.7.15
116 +----+----+----+----+----+----+----+----+----+----+----+----+----+----+----+---
117 | 00 |CTRL|CHECKSUM | 02 | _b | _o | _o | _t | _l | _o | _a | _d | _e | _r | _V
118 +----+----+----+----+----+----+----+----+----+----+----+----+----+----+----+---
119 | _e | _r | _s | _i | _o | _n | \0 | _1 | _. | _3 | _. | _7 | _. | _1 | _5 | \0
120 +----+----+----+----+----+----+----+----+----+----+----+----+----+----+----+---
121 
122 Data is padded with 0xFF
123 
124 */
125 
126 #define PSP_ENV_SIZE  4096
127 
128 static char psp_env_data[PSP_ENV_SIZE] = { 0, };
129 
130 static char * __init lookup_psp_var_map(u8 num)
131 {
132 	int i;
133 
134 	for (i = 0; i < ARRAY_SIZE(psp_var_map); i++)
135 		if (psp_var_map[i].num == num)
136 			return psp_var_map[i].value;
137 
138 	return NULL;
139 }
140 
141 static void __init add_adam2_var(char *name, char *value)
142 {
143 	int i;
144 
145 	for (i = 0; i < MAX_ENTRY; i++) {
146 		if (!adam2_env[i].name) {
147 			adam2_env[i].name = name;
148 			adam2_env[i].value = value;
149 			return;
150 		} else if (!strcmp(adam2_env[i].name, name)) {
151 			adam2_env[i].value = value;
152 			return;
153 		}
154 	}
155 }
156 
157 static int __init parse_psp_env(void *psp_env_base)
158 {
159 	int i, n;
160 	char *name, *value;
161 	struct psp_env_chunk *chunks = (struct psp_env_chunk *)psp_env_data;
162 
163 	memcpy_fromio(chunks, psp_env_base, PSP_ENV_SIZE);
164 
165 	i = 1;
166 	n = PSP_ENV_SIZE / sizeof(struct psp_env_chunk);
167 	while (i < n) {
168 		if ((chunks[i].num == 0xff) || ((i + chunks[i].len) > n))
169 			break;
170 		value = chunks[i].data;
171 		if (chunks[i].num) {
172 			name = lookup_psp_var_map(chunks[i].num);
173 		} else {
174 			name = value;
175 			value += strlen(name) + 1;
176 		}
177 		if (name)
178 			add_adam2_var(name, value);
179 		i += chunks[i].len;
180 	}
181 	return 0;
182 }
183 
184 static void __init ar7_init_env(struct env_var *env)
185 {
186 	int i;
187 	struct psbl_rec *psbl = (struct psbl_rec *)(KSEG1ADDR(0x14000300));
188 	void *psp_env = (void *)KSEG1ADDR(psbl->env_base);
189 
190 	if (strcmp(psp_env, psp_env_version) == 0) {
191 		parse_psp_env(psp_env);
192 	} else {
193 		for (i = 0; i < MAX_ENTRY; i++, env++)
194 			if (env->name)
195 				add_adam2_var(env->name, env->value);
196 	}
197 }
198 
199 static void __init console_config(void)
200 {
201 #ifdef CONFIG_SERIAL_8250_CONSOLE
202 	char console_string[40];
203 	int baud = 0;
204 	char parity = '\0', bits = '\0', flow = '\0';
205 	char *s, *p;
206 
207 	if (strstr(arcs_cmdline, "console="))
208 		return;
209 
210 	s = prom_getenv("modetty0");
211 	if (s) {
212 		baud = simple_strtoul(s, &p, 10);
213 		s = p;
214 		if (*s == ',')
215 			s++;
216 		if (*s)
217 			parity = *s++;
218 		if (*s == ',')
219 			s++;
220 		if (*s)
221 			bits = *s++;
222 		if (*s == ',')
223 			s++;
224 		if (*s == 'h')
225 			flow = 'r';
226 	}
227 
228 	if (baud == 0)
229 		baud = 38400;
230 	if (parity != 'n' && parity != 'o' && parity != 'e')
231 		parity = 'n';
232 	if (bits != '7' && bits != '8')
233 		bits = '8';
234 
235 	if (flow == 'r')
236 		sprintf(console_string, " console=ttyS0,%d%c%c%c", baud,
237 			parity, bits, flow);
238 	else
239 		sprintf(console_string, " console=ttyS0,%d%c%c", baud, parity,
240 			bits);
241 	strlcat(arcs_cmdline, console_string, COMMAND_LINE_SIZE);
242 #endif
243 }
244 
245 void __init prom_init(void)
246 {
247 	ar7_init_cmdline(fw_arg0, (char **)fw_arg1);
248 	ar7_init_env((struct env_var *)fw_arg2);
249 	console_config();
250 }
251 
252 #define PORT(offset) (KSEG1ADDR(AR7_REGS_UART0 + (offset * 4)))
253 static inline unsigned int serial_in(int offset)
254 {
255 	return readl((void *)PORT(offset));
256 }
257 
258 static inline void serial_out(int offset, int value)
259 {
260 	writel(value, (void *)PORT(offset));
261 }
262 
263 void prom_putchar(char c)
264 {
265 	while ((serial_in(UART_LSR) & UART_LSR_TEMT) == 0)
266 		;
267 	serial_out(UART_TX, c);
268 }
269