xref: /openbmc/linux/arch/mips/loongson32/common/prom.c (revision 9cfc5c90)
1 /*
2  * Copyright (c) 2011 Zhang, Keguang <keguang.zhang@gmail.com>
3  *
4  * Modified from arch/mips/pnx833x/common/prom.c.
5  *
6  * This program is free software; you can redistribute	it and/or modify it
7  * under  the terms of	the GNU General	 Public License as published by the
8  * Free Software Foundation;  either version 2 of the  License, or (at your
9  * option) any later version.
10  */
11 
12 #include <linux/serial_reg.h>
13 #include <asm/bootinfo.h>
14 
15 #include <loongson1.h>
16 #include <prom.h>
17 
18 int prom_argc;
19 char **prom_argv, **prom_envp;
20 unsigned long memsize, highmemsize;
21 
22 char *prom_getenv(char *envname)
23 {
24 	char **env = prom_envp;
25 	int i;
26 
27 	i = strlen(envname);
28 
29 	while (*env) {
30 		if (strncmp(envname, *env, i) == 0 && *(*env + i) == '=')
31 			return *env + i + 1;
32 		env++;
33 	}
34 
35 	return 0;
36 }
37 
38 static inline unsigned long env_or_default(char *env, unsigned long dfl)
39 {
40 	char *str = prom_getenv(env);
41 	return str ? simple_strtol(str, 0, 0) : dfl;
42 }
43 
44 void __init prom_init_cmdline(void)
45 {
46 	char *c = &(arcs_cmdline[0]);
47 	int i;
48 
49 	for (i = 1; i < prom_argc; i++) {
50 		strcpy(c, prom_argv[i]);
51 		c += strlen(prom_argv[i]);
52 		if (i < prom_argc - 1)
53 			*c++ = ' ';
54 	}
55 	*c = 0;
56 }
57 
58 void __init prom_init(void)
59 {
60 	void __iomem *uart_base;
61 	prom_argc = fw_arg0;
62 	prom_argv = (char **)fw_arg1;
63 	prom_envp = (char **)fw_arg2;
64 
65 	prom_init_cmdline();
66 
67 	memsize = env_or_default("memsize", DEFAULT_MEMSIZE);
68 	highmemsize = env_or_default("highmemsize", 0x0);
69 
70 	if (strstr(arcs_cmdline, "console=ttyS3"))
71 		uart_base = ioremap_nocache(LS1X_UART3_BASE, 0x0f);
72 	else if (strstr(arcs_cmdline, "console=ttyS2"))
73 		uart_base = ioremap_nocache(LS1X_UART2_BASE, 0x0f);
74 	else if (strstr(arcs_cmdline, "console=ttyS1"))
75 		uart_base = ioremap_nocache(LS1X_UART1_BASE, 0x0f);
76 	else
77 		uart_base = ioremap_nocache(LS1X_UART0_BASE, 0x0f);
78 	setup_8250_early_printk_port((unsigned long)uart_base, 0, 0);
79 }
80 
81 void __init prom_free_prom_memory(void)
82 {
83 }
84