xref: /openbmc/linux/arch/mips/ar7/prom.c (revision 174cd4b1)
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 
29 #include <asm/mach-ar7/ar7.h>
30 #include <asm/mach-ar7/prom.h>
31 
32 #define MAX_ENTRY 80
33 
34 struct env_var {
35 	char	*name;
36 	char	*value;
37 };
38 
39 static struct env_var adam2_env[MAX_ENTRY];
40 
41 char *prom_getenv(const char *name)
42 {
43 	int i;
44 
45 	for (i = 0; (i < MAX_ENTRY) && adam2_env[i].name; i++)
46 		if (!strcmp(name, adam2_env[i].name))
47 			return adam2_env[i].value;
48 
49 	return NULL;
50 }
51 EXPORT_SYMBOL(prom_getenv);
52 
53 static void  __init ar7_init_cmdline(int argc, char *argv[])
54 {
55 	int i;
56 
57 	for (i = 1; i < argc; i++) {
58 		strlcat(arcs_cmdline, argv[i], COMMAND_LINE_SIZE);
59 		if (i < (argc - 1))
60 			strlcat(arcs_cmdline, " ", COMMAND_LINE_SIZE);
61 	}
62 }
63 
64 struct psbl_rec {
65 	u32	psbl_size;
66 	u32	env_base;
67 	u32	env_size;
68 	u32	ffs_base;
69 	u32	ffs_size;
70 };
71 
72 static const char psp_env_version[] __initconst = "TIENV0.8";
73 
74 struct psp_env_chunk {
75 	u8	num;
76 	u8	ctrl;
77 	u16	csum;
78 	u8	len;
79 	char	data[11];
80 } __packed;
81 
82 struct psp_var_map_entry {
83 	u8	num;
84 	char	*value;
85 };
86 
87 static const struct psp_var_map_entry psp_var_map[] = {
88 	{  1,	"cpufrequency" },
89 	{  2,	"memsize" },
90 	{  3,	"flashsize" },
91 	{  4,	"modetty0" },
92 	{  5,	"modetty1" },
93 	{  8,	"maca" },
94 	{  9,	"macb" },
95 	{ 28,	"sysfrequency" },
96 	{ 38,	"mipsfrequency" },
97 };
98 
99 /*
100 
101 Well-known variable (num is looked up in table above for matching variable name)
102 Example: cpufrequency=211968000
103 +----+----+----+----+----+----+----+----+----+----+----+----+----+----+----+---
104 | 01 |CTRL|CHECKSUM | 01 | _2 | _1 | _1 | _9 | _6 | _8 | _0 | _0 | _0 | \0 | FF
105 +----+----+----+----+----+----+----+----+----+----+----+----+----+----+----+---
106 
107 Name=Value pair in a single chunk
108 Example: NAME=VALUE
109 +----+----+----+----+----+----+----+----+----+----+----+----+----+----+----+---
110 | 00 |CTRL|CHECKSUM | 01 | _N | _A | _M | _E | _0 | _V | _A | _L | _U | _E | \0
111 +----+----+----+----+----+----+----+----+----+----+----+----+----+----+----+---
112 
113 Name=Value pair in 2 chunks (len is the number of chunks)
114 Example: bootloaderVersion=1.3.7.15
115 +----+----+----+----+----+----+----+----+----+----+----+----+----+----+----+---
116 | 00 |CTRL|CHECKSUM | 02 | _b | _o | _o | _t | _l | _o | _a | _d | _e | _r | _V
117 +----+----+----+----+----+----+----+----+----+----+----+----+----+----+----+---
118 | _e | _r | _s | _i | _o | _n | \0 | _1 | _. | _3 | _. | _7 | _. | _1 | _5 | \0
119 +----+----+----+----+----+----+----+----+----+----+----+----+----+----+----+---
120 
121 Data is padded with 0xFF
122 
123 */
124 
125 #define PSP_ENV_SIZE  4096
126 
127 static char psp_env_data[PSP_ENV_SIZE] = { 0, };
128 
129 static char * __init lookup_psp_var_map(u8 num)
130 {
131 	int i;
132 
133 	for (i = 0; i < ARRAY_SIZE(psp_var_map); i++)
134 		if (psp_var_map[i].num == num)
135 			return psp_var_map[i].value;
136 
137 	return NULL;
138 }
139 
140 static void __init add_adam2_var(char *name, char *value)
141 {
142 	int i;
143 
144 	for (i = 0; i < MAX_ENTRY; i++) {
145 		if (!adam2_env[i].name) {
146 			adam2_env[i].name = name;
147 			adam2_env[i].value = value;
148 			return;
149 		} else if (!strcmp(adam2_env[i].name, name)) {
150 			adam2_env[i].value = value;
151 			return;
152 		}
153 	}
154 }
155 
156 static int __init parse_psp_env(void *psp_env_base)
157 {
158 	int i, n;
159 	char *name, *value;
160 	struct psp_env_chunk *chunks = (struct psp_env_chunk *)psp_env_data;
161 
162 	memcpy_fromio(chunks, psp_env_base, PSP_ENV_SIZE);
163 
164 	i = 1;
165 	n = PSP_ENV_SIZE / sizeof(struct psp_env_chunk);
166 	while (i < n) {
167 		if ((chunks[i].num == 0xff) || ((i + chunks[i].len) > n))
168 			break;
169 		value = chunks[i].data;
170 		if (chunks[i].num) {
171 			name = lookup_psp_var_map(chunks[i].num);
172 		} else {
173 			name = value;
174 			value += strlen(name) + 1;
175 		}
176 		if (name)
177 			add_adam2_var(name, value);
178 		i += chunks[i].len;
179 	}
180 	return 0;
181 }
182 
183 static void __init ar7_init_env(struct env_var *env)
184 {
185 	int i;
186 	struct psbl_rec *psbl = (struct psbl_rec *)(KSEG1ADDR(0x14000300));
187 	void *psp_env = (void *)KSEG1ADDR(psbl->env_base);
188 
189 	if (strcmp(psp_env, psp_env_version) == 0) {
190 		parse_psp_env(psp_env);
191 	} else {
192 		for (i = 0; i < MAX_ENTRY; i++, env++)
193 			if (env->name)
194 				add_adam2_var(env->name, env->value);
195 	}
196 }
197 
198 static void __init console_config(void)
199 {
200 #ifdef CONFIG_SERIAL_8250_CONSOLE
201 	char console_string[40];
202 	int baud = 0;
203 	char parity = '\0', bits = '\0', flow = '\0';
204 	char *s, *p;
205 
206 	if (strstr(arcs_cmdline, "console="))
207 		return;
208 
209 	s = prom_getenv("modetty0");
210 	if (s) {
211 		baud = simple_strtoul(s, &p, 10);
212 		s = p;
213 		if (*s == ',')
214 			s++;
215 		if (*s)
216 			parity = *s++;
217 		if (*s == ',')
218 			s++;
219 		if (*s)
220 			bits = *s++;
221 		if (*s == ',')
222 			s++;
223 		if (*s == 'h')
224 			flow = 'r';
225 	}
226 
227 	if (baud == 0)
228 		baud = 38400;
229 	if (parity != 'n' && parity != 'o' && parity != 'e')
230 		parity = 'n';
231 	if (bits != '7' && bits != '8')
232 		bits = '8';
233 
234 	if (flow == 'r')
235 		sprintf(console_string, " console=ttyS0,%d%c%c%c", baud,
236 			parity, bits, flow);
237 	else
238 		sprintf(console_string, " console=ttyS0,%d%c%c", baud, parity,
239 			bits);
240 	strlcat(arcs_cmdline, console_string, COMMAND_LINE_SIZE);
241 #endif
242 }
243 
244 void __init prom_init(void)
245 {
246 	ar7_init_cmdline(fw_arg0, (char **)fw_arg1);
247 	ar7_init_env((struct env_var *)fw_arg2);
248 	console_config();
249 
250 	ar7_gpio_init();
251 }
252 
253 #define PORT(offset) (KSEG1ADDR(AR7_REGS_UART0 + (offset * 4)))
254 static inline unsigned int serial_in(int offset)
255 {
256 	return readl((void *)PORT(offset));
257 }
258 
259 static inline void serial_out(int offset, int value)
260 {
261 	writel(value, (void *)PORT(offset));
262 }
263 
264 int prom_putchar(char c)
265 {
266 	while ((serial_in(UART_LSR) & UART_LSR_TEMT) == 0)
267 		;
268 	serial_out(UART_TX, c);
269 	return 1;
270 }
271