summaryrefslogtreecommitdiffstats
path: root/arch/sh/kernel/early_printk.c
blob: 60340823798ab99f19d13ab31af5e3eb1ff45369 (plain) (blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
/*
 * arch/sh/kernel/early_printk.c
 *
 *  Copyright (C) 1999, 2000  Niibe Yutaka
 *  Copyright (C) 2002  M. R. Brown
 *  Copyright (C) 2004 - 2006  Paul Mundt
 *
 * This file is subject to the terms and conditions of the GNU General Public
 * License.  See the file "COPYING" in the main directory of this archive
 * for more details.
 */
#include <linux/console.h>
#include <linux/tty.h>
#include <linux/init.h>
#include <linux/io.h>

#ifdef CONFIG_SH_STANDARD_BIOS
#include <asm/sh_bios.h>

/*
 *	Print a string through the BIOS
 */
static void sh_console_write(struct console *co, const char *s,
				 unsigned count)
{
	sh_bios_console_write(s, count);
}

/*
 *	Setup initial baud/bits/parity. We do two things here:
 *	- construct a cflag setting for the first rs_open()
 *	- initialize the serial port
 *	Return non-zero if we didn't find a serial port.
 */
static int __init sh_console_setup(struct console *co, char *options)
{
	int	cflag = CREAD | HUPCL | CLOCAL;

	/*
	 *	Now construct a cflag setting.
	 *	TODO: this is a totally bogus cflag, as we have
	 *	no idea what serial settings the BIOS is using, or
	 *	even if its using the serial port at all.
	 */
	cflag |= B115200 | CS8 | /*no parity*/0;

	co->cflag = cflag;

	return 0;
}

static struct console bios_console = {
	.name		= "bios",
	.write		= sh_console_write,
	.setup		= sh_console_setup,
	.flags		= CON_PRINTBUFFER,
	.index		= -1,
};
#endif

#ifdef CONFIG_EARLY_SCIF_CONSOLE
#include <linux/serial_core.h>
#include "../../../drivers/serial/sh-sci.h"

static struct uart_port scif_port = {
	.mapbase	= CONFIG_EARLY_SCIF_CONSOLE_PORT,
	.membase	= (char __iomem *)CONFIG_EARLY_SCIF_CONSOLE_PORT,
};

static void scif_sercon_putc(int c)
{
	while (((sci_in(&scif_port, SCFDR) & 0x1f00 >> 8) == 16))
		;

	sci_out(&scif_port, SCxTDR, c);
	sci_in(&scif_port, SCxSR);
	sci_out(&scif_port, SCxSR, 0xf3 & ~(0x20 | 0x40));

	while ((sci_in(&scif_port, SCxSR) & 0x40) == 0);
		;

	if (c == '\n')
		scif_sercon_putc('\r');
}

static void scif_sercon_write(struct console *con, const char *s,
			      unsigned count)
{
	while (count-- > 0)
		scif_sercon_putc(*s++);
}

static int __init scif_sercon_setup(struct console *con, char *options)
{
	con->cflag = CREAD | HUPCL | CLOCAL | B115200 | CS8;

	return 0;
}

static struct console scif_console = {
	.name		= "sercon",
	.write		= scif_sercon_write,
	.setup		= scif_sercon_setup,
	.flags		= CON_PRINTBUFFER,
	.index		= -1,
};

#if defined(CONFIG_CPU_SH4) && !defined(CONFIG_SH_STANDARD_BIOS)
/*
 * Simple SCIF init, primarily aimed at SH7750 and other similar SH-4
 * devices that aren't using sh-ipl+g.
 */
static void scif_sercon_init(int baud)
{
	ctrl_outw(0, scif_port.mapbase + 8);
	ctrl_outw(0, scif_port.mapbase);

	/* Set baud rate */
	ctrl_outb((CONFIG_SH_PCLK_FREQ + 16 * baud) /
		  (32 * baud) - 1, scif_port.mapbase + 4);

	ctrl_outw(12, scif_port.mapbase + 24);
	ctrl_outw(8, scif_port.mapbase + 24);
	ctrl_outw(0, scif_port.mapbase + 32);
	ctrl_outw(0x60, scif_port.mapbase + 16);
	ctrl_outw(0, scif_port.mapbase + 36);
	ctrl_outw(0x30, scif_port.mapbase + 8);
}
#endif /* CONFIG_CPU_SH4 && !CONFIG_SH_STANDARD_BIOS */
#endif /* CONFIG_EARLY_SCIF_CONSOLE */

/*
 * Setup a default console, if more than one is compiled in, rely on the
 * earlyprintk= parsing to give priority.
 */
static struct console *early_console =
#ifdef CONFIG_SH_STANDARD_BIOS
	&bios_console
#elif defined(CONFIG_EARLY_SCIF_CONSOLE)
	&scif_console
#else
	NULL
#endif
	;

static int __initdata keep_early;

int __init setup_early_printk(char *opt)
{
	char *space;
	char buf[256];

	strlcpy(buf, opt, sizeof(buf));
	space = strchr(buf, ' ');
	if (space)
		*space = 0;

	if (strstr(buf, "keep"))
		keep_early = 1;

#ifdef CONFIG_SH_STANDARD_BIOS
	if (!strncmp(buf, "bios", 4))
		early_console = &bios_console;
#endif
#if defined(CONFIG_EARLY_SCIF_CONSOLE)
	if (!strncmp(buf, "serial", 6)) {
		early_console = &scif_console;

#if defined(CONFIG_CPU_SH4) && !defined(CONFIG_SH_STANDARD_BIOS)
		scif_sercon_init(115200);
#endif
	}
#endif

	if (likely(early_console))
		register_console(early_console);

	return 1;
}
__setup("earlyprintk=", setup_early_printk);

void __init disable_early_printk(void)
{
	if (!keep_early) {
		printk("disabling early console\n");
		unregister_console(early_console);
	} else
		printk("keeping early console\n");
}