xref: /openbmc/u-boot/drivers/serial/serial_ns16550.c (revision ac63f2a2)

/*
 * (C) Copyright 2000
 * Rob Taylor, Flying Pig Systems. robt@flyingpig.com.
 *
 * See file CREDITS for list of people who contributed to this
 * project.
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License as
 * published by the Free Software Foundation; either version 2 of
 * the License, or (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
 * MA 02111-1307 USA
 */

#include <common.h>
#include <linux/compiler.h>

#include <ns16550.h>
#ifdef CONFIG_NS87308
#include <ns87308.h>
#endif

#include <serial.h>

DECLARE_GLOBAL_DATA_PTR;

#if !defined(CONFIG_CONS_INDEX)
#elif (CONFIG_CONS_INDEX < 1) || (CONFIG_CONS_INDEX > 4)
#error	"Invalid console index value."
#endif

#if CONFIG_CONS_INDEX == 1 && !defined(CONFIG_SYS_NS16550_COM1)
#error	"Console port 1 defined but not configured."
#elif CONFIG_CONS_INDEX == 2 && !defined(CONFIG_SYS_NS16550_COM2)
#error	"Console port 2 defined but not configured."
#elif CONFIG_CONS_INDEX == 3 && !defined(CONFIG_SYS_NS16550_COM3)
#error	"Console port 3 defined but not configured."
#elif CONFIG_CONS_INDEX == 4 && !defined(CONFIG_SYS_NS16550_COM4)
#error	"Console port 4 defined but not configured."
#endif

/* Note: The port number specified in the functions is 1 based.
 *	 the array is 0 based.
 */
static NS16550_t serial_ports[4] = {
#ifdef CONFIG_SYS_NS16550_COM1
	(NS16550_t)CONFIG_SYS_NS16550_COM1,
#else
	NULL,
#endif
#ifdef CONFIG_SYS_NS16550_COM2
	(NS16550_t)CONFIG_SYS_NS16550_COM2,
#else
	NULL,
#endif
#ifdef CONFIG_SYS_NS16550_COM3
	(NS16550_t)CONFIG_SYS_NS16550_COM3,
#else
	NULL,
#endif
#ifdef CONFIG_SYS_NS16550_COM4
	(NS16550_t)CONFIG_SYS_NS16550_COM4
#else
	NULL
#endif
};

#define PORT	serial_ports[port-1]

/* Multi serial device functions */
#define DECLARE_ESERIAL_FUNCTIONS(port) \
	static int  eserial##port##_init(void) \
	{ \
		int clock_divisor; \
		clock_divisor = calc_divisor(serial_ports[port-1]); \
		NS16550_init(serial_ports[port-1], clock_divisor); \
		return 0 ; \
	} \
	static void eserial##port##_setbrg(void) \
	{ \
		serial_setbrg_dev(port); \
	} \
	static int  eserial##port##_getc(void) \
	{ \
		return serial_getc_dev(port); \
	} \
	static int  eserial##port##_tstc(void) \
	{ \
		return serial_tstc_dev(port); \
	} \
	static void eserial##port##_putc(const char c) \
	{ \
		serial_putc_dev(port, c); \
	} \
	static void eserial##port##_puts(const char *s) \
	{ \
		serial_puts_dev(port, s); \
	}

/* Serial device descriptor */
#define INIT_ESERIAL_STRUCTURE(port, __name) {	\
	.name	= __name,			\
	.start	= eserial##port##_init,		\
	.stop	= NULL,				\
	.setbrg	= eserial##port##_setbrg,	\
	.getc	= eserial##port##_getc,		\
	.tstc	= eserial##port##_tstc,		\
	.putc	= eserial##port##_putc,		\
	.puts	= eserial##port##_puts,		\
}

static int calc_divisor (NS16550_t port)
{
#ifdef CONFIG_OMAP1510
	/* If can't cleanly clock 115200 set div to 1 */
	if ((CONFIG_SYS_NS16550_CLK == 12000000) && (gd->baudrate == 115200)) {
		port->osc_12m_sel = OSC_12M_SEL;	/* enable 6.5 * divisor */
		return (1);				/* return 1 for base divisor */
	}
	port->osc_12m_sel = 0;			/* clear if previsouly set */
#endif
#ifdef CONFIG_OMAP1610
	/* If can't cleanly clock 115200 set div to 1 */
	if ((CONFIG_SYS_NS16550_CLK == 48000000) && (gd->baudrate == 115200)) {
		return (26);		/* return 26 for base divisor */
	}
#endif

#ifdef CONFIG_APTIX
#define MODE_X_DIV 13
#else
#define MODE_X_DIV 16
#endif

	/* Compute divisor value. Normally, we should simply return:
	 *   CONFIG_SYS_NS16550_CLK) / MODE_X_DIV / gd->baudrate
	 * but we need to round that value by adding 0.5.
	 * Rounding is especially important at high baud rates.
	 */
	return (CONFIG_SYS_NS16550_CLK + (gd->baudrate * (MODE_X_DIV / 2))) /
		(MODE_X_DIV * gd->baudrate);
}

void
_serial_putc(const char c,const int port)
{
	if (c == '\n')
		NS16550_putc(PORT, '\r');

	NS16550_putc(PORT, c);
}

void
_serial_putc_raw(const char c,const int port)
{
	NS16550_putc(PORT, c);
}

void
_serial_puts (const char *s,const int port)
{
	while (*s) {
		_serial_putc (*s++,port);
	}
}


int
_serial_getc(const int port)
{
	return NS16550_getc(PORT);
}

int
_serial_tstc(const int port)
{
	return NS16550_tstc(PORT);
}

void
_serial_setbrg (const int port)
{
	int clock_divisor;

	clock_divisor = calc_divisor(PORT);
	NS16550_reinit(PORT, clock_divisor);
}

static inline void
serial_putc_dev(unsigned int dev_index,const char c)
{
	_serial_putc(c,dev_index);
}

static inline void
serial_putc_raw_dev(unsigned int dev_index,const char c)
{
	_serial_putc_raw(c,dev_index);
}

static inline void
serial_puts_dev(unsigned int dev_index,const char *s)
{
	_serial_puts(s,dev_index);
}

static inline int
serial_getc_dev(unsigned int dev_index)
{
	return _serial_getc(dev_index);
}

static inline int
serial_tstc_dev(unsigned int dev_index)
{
	return _serial_tstc(dev_index);
}

static inline void
serial_setbrg_dev(unsigned int dev_index)
{
	_serial_setbrg(dev_index);
}

DECLARE_ESERIAL_FUNCTIONS(1);
struct serial_device eserial1_device =
	INIT_ESERIAL_STRUCTURE(1, "eserial0");
DECLARE_ESERIAL_FUNCTIONS(2);
struct serial_device eserial2_device =
	INIT_ESERIAL_STRUCTURE(2, "eserial1");
DECLARE_ESERIAL_FUNCTIONS(3);
struct serial_device eserial3_device =
	INIT_ESERIAL_STRUCTURE(3, "eserial2");
DECLARE_ESERIAL_FUNCTIONS(4);
struct serial_device eserial4_device =
	INIT_ESERIAL_STRUCTURE(4, "eserial3");

__weak struct serial_device *default_serial_console(void)
{
#if CONFIG_CONS_INDEX == 1
	return &eserial1_device;
#elif CONFIG_CONS_INDEX == 2
	return &eserial2_device;
#elif CONFIG_CONS_INDEX == 3
	return &eserial3_device;
#elif CONFIG_CONS_INDEX == 4
	return &eserial4_device;
#else
#error "Bad CONFIG_CONS_INDEX."
#endif
}

void ns16550_serial_initialize(void)
{
#if defined(CONFIG_SYS_NS16550_COM1)
	serial_register(&eserial1_device);
#endif
#if defined(CONFIG_SYS_NS16550_COM2)
	serial_register(&eserial2_device);
#endif
#if defined(CONFIG_SYS_NS16550_COM3)
	serial_register(&eserial3_device);
#endif
#if defined(CONFIG_SYS_NS16550_COM4)
	serial_register(&eserial4_device);
#endif
}