linux/arch/sh/kernel/early_printk.c

138 lines
2.9 KiB
C

/*
* arch/sh/kernel/early_printk.c
*
* Copyright (C) 1999, 2000 Niibe Yutaka
* Copyright (C) 2002 M. R. Brown
* Copyright (C) 2004 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 <asm/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 early_console = {
.name = "bios",
.write = sh_console_write,
.setup = sh_console_setup,
.flags = CON_PRINTBUFFER,
.index = -1,
};
#endif
#ifdef CONFIG_EARLY_SCIF_CONSOLE
#define SCIF_REG 0xffe80000
static void scif_sercon_putc(int c)
{
while (!(ctrl_inw(SCIF_REG + 0x10) & 0x20)) ;
ctrl_outb(c, SCIF_REG + 12);
ctrl_outw((ctrl_inw(SCIF_REG + 0x10) & 0x9f), SCIF_REG + 0x10);
if (c == '\n')
scif_sercon_putc('\r');
}
static void scif_sercon_flush(void)
{
ctrl_outw((ctrl_inw(SCIF_REG + 0x10) & 0xbf), SCIF_REG + 0x10);
while (!(ctrl_inw(SCIF_REG + 0x10) & 0x40)) ;
ctrl_outw((ctrl_inw(SCIF_REG + 0x10) & 0xbf), SCIF_REG + 0x10);
}
static void scif_sercon_write(struct console *con, const char *s, unsigned count)
{
while (count-- > 0)
scif_sercon_putc(*s++);
scif_sercon_flush();
}
static int __init scif_sercon_setup(struct console *con, char *options)
{
con->cflag = CREAD | HUPCL | CLOCAL | B115200 | CS8;
return 0;
}
static struct console early_console = {
.name = "sercon",
.write = scif_sercon_write,
.setup = scif_sercon_setup,
.flags = CON_PRINTBUFFER,
.index = -1,
};
void scif_sercon_init(int baud)
{
ctrl_outw(0, SCIF_REG + 8);
ctrl_outw(0, SCIF_REG);
/* Set baud rate */
ctrl_outb((CONFIG_SH_PCLK_FREQ + 16 * baud) /
(32 * baud) - 1, SCIF_REG + 4);
ctrl_outw(12, SCIF_REG + 24);
ctrl_outw(8, SCIF_REG + 24);
ctrl_outw(0, SCIF_REG + 32);
ctrl_outw(0x60, SCIF_REG + 16);
ctrl_outw(0, SCIF_REG + 36);
ctrl_outw(0x30, SCIF_REG + 8);
}
#endif
void __init enable_early_printk(void)
{
#ifdef CONFIG_EARLY_SCIF_CONSOLE
scif_sercon_init(115200);
#endif
register_console(&early_console);
}
void disable_early_printk(void)
{
unregister_console(&early_console);
}