freebsd-skq/sys/dev/uart/uart_cpu_amd64.c
Marcel Moolenaar 2ae4f1fd16 Introduce the hw.uart.console and hw.uart.dbgport environment variables
to select a serial console and debug port (resp). On ia64 these replace
the use of hints completely and take precedence over hints on alpha,
amd64 and i386. On sparc64 these variables are not yet recognised.

The reasons for introducing these variables are:
1.  Hints have side-effects. They reserve the unit number for use by
    isa or acpi devices and therefore cannot be used to select a pci
    device. Also, the use of a unit number to select a device prior
    to bus enumeration is nonsense. The new variables have no side-
    effects and are not based on unit numbers.
2.  Hints don't have the expression power to allow the sysadmin to
    select UARTs that are not legacy PC devices and need the support
    of compile-time constants to give the sysadmin some level of
    flexibility.

The hw.uart.console and hw.uart.dbgport variables specify a list of
attributes. An attribute is a tag-value pair, seperated by a colon.
Attributes are seperated by a comma. Where possible, tags are the
same as those in /etc/remote (only br and pa in practice). Details
can be found in the manpage (not part of this commit).

Not tested on: amd64, pc98
2004-03-20 02:14:02 +00:00

102 lines
3.1 KiB
C

/*
* Copyright (c) 2003, 2004 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.
*/
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/bus.h>
#include <machine/bus.h>
#include <dev/uart/uart.h>
#include <dev/uart/uart_cpu.h>
bus_space_tag_t uart_bus_space_io = AMD64_BUS_SPACE_IO;
bus_space_tag_t uart_bus_space_mem = AMD64_BUS_SPACE_MEM;
int
uart_cpu_eqres(struct uart_bas *b1, struct uart_bas *b2)
{
return ((b1->bsh == b2->bsh && b1->bst == b2->bst) ? 1 : 0);
}
int
uart_cpu_getdev(int devtype, struct uart_devinfo *di)
{
unsigned int i, ivar;
/* Check the environment. */
if (uart_getenv(devtype, di) == 0)
return (0);
/*
* Scan the hints. We only try units 0 to 3 (inclusive). This
* covers the ISA legacy where 4 UARTs had their resources
* predefined.
*/
for (i = 0; i < 4; i++) {
if (resource_int_value("uart", i, "flags", &ivar))
continue;
if (devtype == UART_DEV_CONSOLE && !UART_FLAGS_CONSOLE(ivar))
continue;
if (devtype == UART_DEV_DBGPORT && !UART_FLAGS_DBGPORT(ivar))
continue;
/*
* We have a possible device. Make sure it's enabled and
* that we have an I/O port.
*/
if (resource_int_value("uart", i, "disabled", &ivar) == 0 &&
ivar != 0)
continue;
if (resource_int_value("uart", i, "port", &ivar) != 0 ||
ivar == 0)
continue;
/*
* Got it. Fill in the instance and return it. We only have
* ns8250 and successors on i386.
*/
di->ops = uart_ns8250_ops;
di->bas.chan = 0;
di->bas.bst = uart_bus_space_io;
if (bus_space_map(di->bas.bst, ivar, 8, 0, &di->bas.bsh) != 0)
continue;
di->bas.regshft = 0;
di->bas.rclk = 0;
if (resource_int_value("uart", i, "baud", &ivar) != 0)
ivar = 0;
di->baudrate = ivar;
di->databits = 8;
di->stopbits = 1;
di->parity = UART_PARITY_NONE;
return (0);
}
return (ENXIO);
}