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-rw-r--r--arch/sh/kernel/early_printk.c137
1 files changed, 137 insertions, 0 deletions
diff --git a/arch/sh/kernel/early_printk.c b/arch/sh/kernel/early_printk.c
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1/*
2 * arch/sh/kernel/early_printk.c
3 *
4 * Copyright (C) 1999, 2000 Niibe Yutaka
5 * Copyright (C) 2002 M. R. Brown
6 * Copyright (C) 2004 Paul Mundt
7 *
8 * This file is subject to the terms and conditions of the GNU General Public
9 * License. See the file "COPYING" in the main directory of this archive
10 * for more details.
11 */
12#include <linux/console.h>
13#include <linux/tty.h>
14#include <linux/init.h>
15#include <asm/io.h>
16
17#ifdef CONFIG_SH_STANDARD_BIOS
18#include <asm/sh_bios.h>
19
20/*
21 * Print a string through the BIOS
22 */
23static void sh_console_write(struct console *co, const char *s,
24 unsigned count)
25{
26 sh_bios_console_write(s, count);
27}
28
29/*
30 * Setup initial baud/bits/parity. We do two things here:
31 * - construct a cflag setting for the first rs_open()
32 * - initialize the serial port
33 * Return non-zero if we didn't find a serial port.
34 */
35static int __init sh_console_setup(struct console *co, char *options)
36{
37 int cflag = CREAD | HUPCL | CLOCAL;
38
39 /*
40 * Now construct a cflag setting.
41 * TODO: this is a totally bogus cflag, as we have
42 * no idea what serial settings the BIOS is using, or
43 * even if its using the serial port at all.
44 */
45 cflag |= B115200 | CS8 | /*no parity*/0;
46
47 co->cflag = cflag;
48
49 return 0;
50}
51
52static struct console early_console = {
53 .name = "bios",
54 .write = sh_console_write,
55 .setup = sh_console_setup,
56 .flags = CON_PRINTBUFFER,
57 .index = -1,
58};
59#endif
60
61#ifdef CONFIG_EARLY_SCIF_CONSOLE
62#define SCIF_REG 0xffe80000
63
64static void scif_sercon_putc(int c)
65{
66 while (!(ctrl_inw(SCIF_REG + 0x10) & 0x20)) ;
67
68 ctrl_outb(c, SCIF_REG + 12);
69 ctrl_outw((ctrl_inw(SCIF_REG + 0x10) & 0x9f), SCIF_REG + 0x10);
70
71 if (c == '\n')
72 scif_sercon_putc('\r');
73}
74
75static void scif_sercon_flush(void)
76{
77 ctrl_outw((ctrl_inw(SCIF_REG + 0x10) & 0xbf), SCIF_REG + 0x10);
78
79 while (!(ctrl_inw(SCIF_REG + 0x10) & 0x40)) ;
80
81 ctrl_outw((ctrl_inw(SCIF_REG + 0x10) & 0xbf), SCIF_REG + 0x10);
82}
83
84static void scif_sercon_write(struct console *con, const char *s, unsigned count)
85{
86 while (count-- > 0)
87 scif_sercon_putc(*s++);
88
89 scif_sercon_flush();
90}
91
92static int __init scif_sercon_setup(struct console *con, char *options)
93{
94 con->cflag = CREAD | HUPCL | CLOCAL | B115200 | CS8;
95
96 return 0;
97}
98
99static struct console early_console = {
100 .name = "sercon",
101 .write = scif_sercon_write,
102 .setup = scif_sercon_setup,
103 .flags = CON_PRINTBUFFER,
104 .index = -1,
105};
106
107void scif_sercon_init(int baud)
108{
109 ctrl_outw(0, SCIF_REG + 8);
110 ctrl_outw(0, SCIF_REG);
111
112 /* Set baud rate */
113 ctrl_outb((CONFIG_SH_PCLK_FREQ + 16 * baud) /
114 (32 * baud) - 1, SCIF_REG + 4);
115
116 ctrl_outw(12, SCIF_REG + 24);
117 ctrl_outw(8, SCIF_REG + 24);
118 ctrl_outw(0, SCIF_REG + 32);
119 ctrl_outw(0x60, SCIF_REG + 16);
120 ctrl_outw(0, SCIF_REG + 36);
121 ctrl_outw(0x30, SCIF_REG + 8);
122}
123#endif
124
125void __init enable_early_printk(void)
126{
127#ifdef CONFIG_EARLY_SCIF_CONSOLE
128 scif_sercon_init(115200);
129#endif
130 register_console(&early_console);
131}
132
133void disable_early_printk(void)
134{
135 unregister_console(&early_console);
136}
137