File: /usr/src/linux/arch/mips/mips-boards/generic/printf.c

1     /*
2      * Carsten Langgaard, carstenl@mips.com
3      * Copyright (C) 1999,2000 MIPS Technologies, Inc.  All rights reserved.
4      *
5      * ########################################################################
6      *
7      *  This program is free software; you can distribute it and/or modify it
8      *  under the terms of the GNU General Public License (Version 2) as
9      *  published by the Free Software Foundation.
10      *
11      *  This program is distributed in the hope it will be useful, but WITHOUT
12      *  ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
13      *  FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
14      *  for more details.
15      *
16      *  You should have received a copy of the GNU General Public License along
17      *  with this program; if not, write to the Free Software Foundation, Inc.,
18      *  59 Temple Place - Suite 330, Boston MA 02111-1307, USA.
19      *
20      * ########################################################################
21      *
22      * Putting things on the screen/serial line using YAMONs facilities.
23      *
24      */
25     #include <linux/config.h>
26     #include <linux/init.h>
27     #include <linux/kernel.h>
28     #include <linux/serialP.h>
29     #include <linux/serial_reg.h>
30     #include <asm/system.h>
31     #include <asm/io.h>
32     #include <asm/serial.h>
33     
34     
35     #ifdef CONFIG_MIPS_ATLAS 
36     /* 
37      * Atlas registers are memory mapped on 64-bit aligned boundaries and 
38      * only word access are allowed.
39      * When reading the UART 8 bit registers only the LSB are valid.
40      */
41     unsigned int atlas_serial_in(struct async_struct *info, int offset)
42     {
43     	return (*(volatile unsigned int *)(info->port + mips_io_port_base + offset*8) & 0xff);
44     }
45     
46     void atlas_serial_out(struct async_struct *info, int offset, int value)
47     {
48     	*(volatile unsigned int *)(info->port + mips_io_port_base + offset*8) = value;
49     }
50     
51     #define serial_in  atlas_serial_in
52     #define serial_out atlas_serial_out
53     
54     #else
55     
56     static unsigned int serial_in(struct async_struct *info, int offset)
57     {
58     	return inb(info->port + offset);
59     }
60     
61     static void serial_out(struct async_struct *info, int offset,
62     				int value)
63     {
64     	outb(value, info->port + offset);
65     }
66     #endif
67     
68     static struct serial_state rs_table[] = {
69     	SERIAL_PORT_DFNS	/* Defined in serial.h */
70     };
71     
72     /*
73      * Hooks to fake "prom" console I/O before devices 
74      * are fully initialized. 
75      */
76     static struct async_struct prom_port_info = {0};
77     
78     void __init setup_prom_printf(int tty_no) {
79     	struct serial_state *ser = &rs_table[tty_no];
80     
81     	prom_port_info.state = ser;
82     	prom_port_info.magic = SERIAL_MAGIC;
83     	prom_port_info.port = ser->port;
84     	prom_port_info.flags = ser->flags;
85     
86     	/* No setup of UART - assume YAMON left in sane state */
87     }
88     
89     int putPromChar(char c)
90     {
91             if (!prom_port_info.state) { 	/* need to init device first */
92     		return 0;
93     	}
94     
95     	while ((serial_in(&prom_port_info, UART_LSR) & UART_LSR_THRE) == 0)
96     		;
97     
98     	serial_out(&prom_port_info, UART_TX, c);
99     
100     	return 1;
101     }
102     
103     char getPromChar(void)
104     {
105     	if (!prom_port_info.state) { 	/* need to init device first */
106     		return 0;
107     	}
108     
109     	while (!(serial_in(&prom_port_info, UART_LSR) & 1))
110     		;
111     
112     	return(serial_in(&prom_port_info, UART_RX));
113     }
114     
115     static char buf[1024];
116     
117     void __init prom_printf(char *fmt, ...)
118     {
119     	va_list args;
120     	int l;
121     	char *p, *buf_end;
122     	long flags;
123     
124     	int putPromChar(char);
125     
126     	/* Low level, brute force, not SMP safe... */
127     	save_and_cli(flags);
128     	va_start(args, fmt);
129     	l = vsprintf(buf, fmt, args); /* hopefully i < sizeof(buf) */
130     	va_end(args);
131     
132     	buf_end = buf + l;
133     
134     	for (p = buf; p < buf_end; p++) {
135     		/* Crude cr/nl handling is better than none */
136     		if(*p == '\n')putPromChar('\r');
137     		putPromChar(*p);
138     	}
139     	restore_flags(flags);
140     }
141