xref: /openbmc/linux/arch/mips/ar7/prom.c (revision 75bf465f0bc33e9b776a46d6a1b9b990f5fb7c37)
1  // SPDX-License-Identifier: GPL-2.0-only
2  /*
3   * Carsten Langgaard, carstenl@mips.com
4   * Copyright (C) 1999,2000 MIPS Technologies, Inc.  All rights reserved.
5   *
6   * Putting things on the screen/serial line using YAMONs facilities.
7   */
8  #include <linux/init.h>
9  #include <linux/kernel.h>
10  #include <linux/serial_reg.h>
11  #include <linux/spinlock.h>
12  #include <linux/export.h>
13  #include <linux/string.h>
14  #include <linux/io.h>
15  #include <asm/bootinfo.h>
16  #include <asm/setup.h>
17  
18  #include <asm/mach-ar7/ar7.h>
19  #include <asm/mach-ar7/prom.h>
20  
21  #define MAX_ENTRY 80
22  
23  struct env_var {
24  	char	*name;
25  	char	*value;
26  };
27  
28  static struct env_var adam2_env[MAX_ENTRY];
29  
prom_getenv(const char * name)30  char *prom_getenv(const char *name)
31  {
32  	int i;
33  
34  	for (i = 0; (i < MAX_ENTRY) && adam2_env[i].name; i++)
35  		if (!strcmp(name, adam2_env[i].name))
36  			return adam2_env[i].value;
37  
38  	return NULL;
39  }
40  EXPORT_SYMBOL(prom_getenv);
41  
ar7_init_cmdline(int argc,char * argv[])42  static void  __init ar7_init_cmdline(int argc, char *argv[])
43  {
44  	int i;
45  
46  	for (i = 1; i < argc; i++) {
47  		strlcat(arcs_cmdline, argv[i], COMMAND_LINE_SIZE);
48  		if (i < (argc - 1))
49  			strlcat(arcs_cmdline, " ", COMMAND_LINE_SIZE);
50  	}
51  }
52  
53  struct psbl_rec {
54  	u32	psbl_size;
55  	u32	env_base;
56  	u32	env_size;
57  	u32	ffs_base;
58  	u32	ffs_size;
59  };
60  
61  static const char psp_env_version[] __initconst = "TIENV0.8";
62  
63  struct psp_env_chunk {
64  	u8	num;
65  	u8	ctrl;
66  	u16	csum;
67  	u8	len;
68  	char	data[11];
69  } __packed;
70  
71  struct psp_var_map_entry {
72  	u8	num;
73  	char	*value;
74  };
75  
76  static const struct psp_var_map_entry psp_var_map[] = {
77  	{  1,	"cpufrequency" },
78  	{  2,	"memsize" },
79  	{  3,	"flashsize" },
80  	{  4,	"modetty0" },
81  	{  5,	"modetty1" },
82  	{  8,	"maca" },
83  	{  9,	"macb" },
84  	{ 28,	"sysfrequency" },
85  	{ 38,	"mipsfrequency" },
86  };
87  
88  /*
89  
90  Well-known variable (num is looked up in table above for matching variable name)
91  Example: cpufrequency=211968000
92  +----+----+----+----+----+----+----+----+----+----+----+----+----+----+----+---
93  | 01 |CTRL|CHECKSUM | 01 | _2 | _1 | _1 | _9 | _6 | _8 | _0 | _0 | _0 | \0 | FF
94  +----+----+----+----+----+----+----+----+----+----+----+----+----+----+----+---
95  
96  Name=Value pair in a single chunk
97  Example: NAME=VALUE
98  +----+----+----+----+----+----+----+----+----+----+----+----+----+----+----+---
99  | 00 |CTRL|CHECKSUM | 01 | _N | _A | _M | _E | _0 | _V | _A | _L | _U | _E | \0
100  +----+----+----+----+----+----+----+----+----+----+----+----+----+----+----+---
101  
102  Name=Value pair in 2 chunks (len is the number of chunks)
103  Example: bootloaderVersion=1.3.7.15
104  +----+----+----+----+----+----+----+----+----+----+----+----+----+----+----+---
105  | 00 |CTRL|CHECKSUM | 02 | _b | _o | _o | _t | _l | _o | _a | _d | _e | _r | _V
106  +----+----+----+----+----+----+----+----+----+----+----+----+----+----+----+---
107  | _e | _r | _s | _i | _o | _n | \0 | _1 | _. | _3 | _. | _7 | _. | _1 | _5 | \0
108  +----+----+----+----+----+----+----+----+----+----+----+----+----+----+----+---
109  
110  Data is padded with 0xFF
111  
112  */
113  
114  #define PSP_ENV_SIZE  4096
115  
116  static char psp_env_data[PSP_ENV_SIZE] = { 0, };
117  
lookup_psp_var_map(u8 num)118  static char * __init lookup_psp_var_map(u8 num)
119  {
120  	int i;
121  
122  	for (i = 0; i < ARRAY_SIZE(psp_var_map); i++)
123  		if (psp_var_map[i].num == num)
124  			return psp_var_map[i].value;
125  
126  	return NULL;
127  }
128  
add_adam2_var(char * name,char * value)129  static void __init add_adam2_var(char *name, char *value)
130  {
131  	int i;
132  
133  	for (i = 0; i < MAX_ENTRY; i++) {
134  		if (!adam2_env[i].name) {
135  			adam2_env[i].name = name;
136  			adam2_env[i].value = value;
137  			return;
138  		} else if (!strcmp(adam2_env[i].name, name)) {
139  			adam2_env[i].value = value;
140  			return;
141  		}
142  	}
143  }
144  
parse_psp_env(void * psp_env_base)145  static int __init parse_psp_env(void *psp_env_base)
146  {
147  	int i, n;
148  	char *name, *value;
149  	struct psp_env_chunk *chunks = (struct psp_env_chunk *)psp_env_data;
150  
151  	memcpy_fromio(chunks, psp_env_base, PSP_ENV_SIZE);
152  
153  	i = 1;
154  	n = PSP_ENV_SIZE / sizeof(struct psp_env_chunk);
155  	while (i < n) {
156  		if ((chunks[i].num == 0xff) || ((i + chunks[i].len) > n))
157  			break;
158  		value = chunks[i].data;
159  		if (chunks[i].num) {
160  			name = lookup_psp_var_map(chunks[i].num);
161  		} else {
162  			name = value;
163  			value += strlen(name) + 1;
164  		}
165  		if (name)
166  			add_adam2_var(name, value);
167  		i += chunks[i].len;
168  	}
169  	return 0;
170  }
171  
ar7_init_env(struct env_var * env)172  static void __init ar7_init_env(struct env_var *env)
173  {
174  	int i;
175  	struct psbl_rec *psbl = (struct psbl_rec *)(KSEG1ADDR(0x14000300));
176  	void *psp_env = (void *)KSEG1ADDR(psbl->env_base);
177  
178  	if (strcmp(psp_env, psp_env_version) == 0) {
179  		parse_psp_env(psp_env);
180  	} else {
181  		for (i = 0; i < MAX_ENTRY; i++, env++)
182  			if (env->name)
183  				add_adam2_var(env->name, env->value);
184  	}
185  }
186  
console_config(void)187  static void __init console_config(void)
188  {
189  #ifdef CONFIG_SERIAL_8250_CONSOLE
190  	char console_string[40];
191  	int baud = 0;
192  	char parity = '\0', bits = '\0', flow = '\0';
193  	char *s, *p;
194  
195  	if (strstr(arcs_cmdline, "console="))
196  		return;
197  
198  	s = prom_getenv("modetty0");
199  	if (s) {
200  		baud = simple_strtoul(s, &p, 10);
201  		s = p;
202  		if (*s == ',')
203  			s++;
204  		if (*s)
205  			parity = *s++;
206  		if (*s == ',')
207  			s++;
208  		if (*s)
209  			bits = *s++;
210  		if (*s == ',')
211  			s++;
212  		if (*s == 'h')
213  			flow = 'r';
214  	}
215  
216  	if (baud == 0)
217  		baud = 38400;
218  	if (parity != 'n' && parity != 'o' && parity != 'e')
219  		parity = 'n';
220  	if (bits != '7' && bits != '8')
221  		bits = '8';
222  
223  	if (flow == 'r')
224  		sprintf(console_string, " console=ttyS0,%d%c%c%c", baud,
225  			parity, bits, flow);
226  	else
227  		sprintf(console_string, " console=ttyS0,%d%c%c", baud, parity,
228  			bits);
229  	strlcat(arcs_cmdline, console_string, COMMAND_LINE_SIZE);
230  #endif
231  }
232  
prom_init(void)233  void __init prom_init(void)
234  {
235  	ar7_init_cmdline(fw_arg0, (char **)fw_arg1);
236  	ar7_init_env((struct env_var *)fw_arg2);
237  	console_config();
238  }
239  
240  #define PORT(offset) (KSEG1ADDR(AR7_REGS_UART0 + (offset * 4)))
serial_in(int offset)241  static inline unsigned int serial_in(int offset)
242  {
243  	return readl((void *)PORT(offset));
244  }
245  
serial_out(int offset,int value)246  static inline void serial_out(int offset, int value)
247  {
248  	writel(value, (void *)PORT(offset));
249  }
250  
prom_putchar(char c)251  void prom_putchar(char c)
252  {
253  	while ((serial_in(UART_LSR) & UART_LSR_TEMT) == 0)
254  		;
255  	serial_out(UART_TX, c);
256  }
257