diff options
Diffstat (limited to 'arch/sh/kernel/early_printk.c')
-rw-r--r-- | arch/sh/kernel/early_printk.c | 137 |
1 files changed, 137 insertions, 0 deletions
diff --git a/arch/sh/kernel/early_printk.c b/arch/sh/kernel/early_printk.c new file mode 100644 index 0000000..1378db3 --- /dev/null +++ b/arch/sh/kernel/early_printk.c @@ -0,0 +1,137 @@ +/* + * 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); +} + |