1
0
mirror of https://git.FreeBSD.org/src.git synced 2024-12-20 11:11:24 +00:00
freebsd/sys/dev/uart/uart.h
Marcel Moolenaar 875f70dba4 Revert the introduction of iobase in struct uart_bas. Both the SAB82532
and the Z8530 drivers used the I/O address as a quick and dirty way to
determine which channel they operated on, but formalizing this by
introducing iobase is not a solution. How for example would a driver
know which channel it controls for a multi-channel UART that only has a
single I/O range?

Instead, add an explicit field, called chan, to struct uart_bas that
holds the channel within a device, or 0 otherwise. The chan field is
initialized both by the system device probing (i.e. a system console)
or it is passed down to uart_bus_probe() by any of the bus front-ends.
As such, it impacts all platforms and bus drivers and makes it a rather
large commit.

Remove the use of iobase in uart_cpu_eqres() for pc98. It is expected
that platforms have the capability to compare tag and handle pairs for
equality; as to determine whether two pairs access the same device or
not. The use of iobase for pc98 makes it impossible to formalize this
and turn it into a real newbus function later. This commit reverts
uart_cpu_eqres() for pc98 to an unimplemented function. It has to be
reimplemented using only the tag and handle fields in struct uart_bas.

Rewrite the SAB82532 and Z8530 drivers to use the chan field in struct
uart_bas. Remove the IS_CHANNEL_A and IS_CHANNEL_B macros. We don't
need to abstract anything anymore.

Discussed with: nyan
Tested on: i386, ia64, sparc64
2003-09-26 05:14:56 +00:00

84 lines
2.9 KiB
C

/*
* 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_ */