xref: /freebsd/sys/dev/uart/uart.h (revision 875f70dba4ac5331af98ce31da9e3f02bdf2af21)

/*
 * Copyright (c) 2003 Marcel Moolenaar
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 *
 * $FreeBSD$
 */

#ifndef _DEV_UART_H_
#define _DEV_UART_H_

/*
 * Bus access structure. This structure holds the minimum information needed
 * to access the UART. The rclk field, although not important to actually
 * access the UART, is important for baudrate programming, delay loops and
 * other timing related computations.
 */
struct uart_bas {
	bus_space_tag_t bst;
	bus_space_handle_t bsh;
	u_int	chan;
	u_int	rclk;
	u_int	regshft;
};

#define	uart_regofs(bas, reg)		((reg) << (bas)->regshft)

#define	uart_getreg(bas, reg)		\
	bus_space_read_1((bas)->bst, (bas)->bsh, uart_regofs(bas, reg))
#define	uart_setreg(bas, reg, value)	\
	bus_space_write_1((bas)->bst, (bas)->bsh, uart_regofs(bas, reg), value)

/* 16-bit I/O (e.g. to divisor latch) */
#define	uart_getdreg(bas, reg)		\
	bus_space_read_2((bas)->bst, (bas)->bsh, uart_regofs(bas, reg))
#define	uart_setdreg(bas, reg, value)	\
	bus_space_write_2((bas)->bst, (bas)->bsh, uart_regofs(bas, reg), value)

/*
 * XXX we don't know the length of the bus space address range in use by
 * the UART. Since barriers don't use the length field currently, we put
 * a zero there for now.
 */
#define uart_barrier(bas)		\
	bus_space_barrier((bas)->bst, (bas)->bsh, 0, 0,		\
	    BUS_SPACE_BARRIER_READ|BUS_SPACE_BARRIER_WRITE)

/*
 * Device flags.
 */
#define	UART_FLAGS_CONSOLE(f)		((f) & 0x10)
#define	UART_FLAGS_DBGPORT(f)		((f) & 0x80)

/*
 * Data parity values (magical numbers related to ns8250).
 */
#define	UART_PARITY_NONE		0
#define	UART_PARITY_ODD			1
#define	UART_PARITY_EVEN		3
#define	UART_PARITY_MARK		5
#define	UART_PARITY_SPACE		7

#endif /* _DEV_UART_H_ */