freebsd-skq/sys/dev/uart/uart_bus_fdt.c
imp 8c1e434d15 Make clock optional on uart nodes. It is a FreeBSD-specific extention,
and won't be present in vendor supplied dts files.
2014-03-08 03:39:09 +00:00

159 lines
4.9 KiB
C

/*-
* Copyright (c) 2009-2010 The FreeBSD Foundation
* All rights reserved.
*
* This software was developed by Semihalf under sponsorship from
* the FreeBSD Foundation.
*
* 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 AND CONTRIBUTORS ``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 OR CONTRIBUTORS 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 "opt_platform.h"
#include <sys/param.h>
#include <sys/bus.h>
#include <sys/kernel.h>
#include <sys/module.h>
#include <machine/bus.h>
#include <dev/fdt/fdt_common.h>
#include <dev/ofw/ofw_bus.h>
#include <dev/ofw/ofw_bus_subr.h>
#include <dev/uart/uart.h>
#include <dev/uart/uart_bus.h>
#include <dev/uart/uart_cpu.h>
static int uart_fdt_probe(device_t);
static device_method_t uart_fdt_methods[] = {
/* Device interface */
DEVMETHOD(device_probe, uart_fdt_probe),
DEVMETHOD(device_attach, uart_bus_attach),
DEVMETHOD(device_detach, uart_bus_detach),
{ 0, 0 }
};
static driver_t uart_fdt_driver = {
uart_driver_name,
uart_fdt_methods,
sizeof(struct uart_softc),
};
/*
* Compatible devices. Keep this sorted in most- to least-specific order first,
* alphabetical second. That is, "zwie,ns16550" should appear before "ns16550"
* on the theory that the zwie driver knows how to make better use of the
* hardware than the generic driver. Likewise with chips within a family, the
* highest-numbers / most recent models should probably appear earlier.
*/
static struct ofw_compat_data compat_data[] = {
{"arm,pl011", (uintptr_t)&uart_pl011_class},
{"atmel,at91rm9200-usart",(uintptr_t)&at91_usart_class},
{"atmel,at91sam9260-usart",(uintptr_t)&at91_usart_class},
{"cadence,uart", (uintptr_t)&uart_cdnc_class},
{"exynos", (uintptr_t)&uart_s3c2410_class},
{"fsl,imx6q-uart", (uintptr_t)&uart_imx_class},
{"fsl,imx53-uart", (uintptr_t)&uart_imx_class},
{"fsl,imx51-uart", (uintptr_t)&uart_imx_class},
{"fsl,imx31-uart", (uintptr_t)&uart_imx_class},
{"fsl,imx27-uart", (uintptr_t)&uart_imx_class},
{"fsl,imx25-uart", (uintptr_t)&uart_imx_class},
{"fsl,imx21-uart", (uintptr_t)&uart_imx_class},
{"fsl,mvf600-uart", (uintptr_t)&uart_vybrid_class},
{"lpc,uart", (uintptr_t)&uart_lpc_class},
{"ti,ns16550", (uintptr_t)&uart_ti8250_class},
{"ns16550", (uintptr_t)&uart_ns8250_class},
{NULL, (uintptr_t)NULL},
};
/* Export the compat_data table for use by the uart_cpu_fdt.c probe routine. */
const struct ofw_compat_data *uart_fdt_compat_data = compat_data;
static int
uart_fdt_get_clock(phandle_t node, pcell_t *cell)
{
pcell_t clock;
/*
* clock-frequency is a FreeBSD-specific hack. Make its presence optional.
*/
if ((OF_getprop(node, "clock-frequency", &clock,
sizeof(clock))) <= 0)
clock = 0;
if (clock == 0)
/* Try to retrieve parent 'bus-frequency' */
/* XXX this should go to simple-bus fixup or so */
if ((OF_getprop(OF_parent(node), "bus-frequency", &clock,
sizeof(clock))) <= 0)
clock = 0;
*cell = fdt32_to_cpu(clock);
return (0);
}
static int
uart_fdt_get_shift(phandle_t node, pcell_t *cell)
{
pcell_t shift;
if ((OF_getprop(node, "reg-shift", &shift, sizeof(shift))) <= 0)
shift = 0;
*cell = fdt32_to_cpu(shift);
return (0);
}
static int
uart_fdt_probe(device_t dev)
{
struct uart_softc *sc;
phandle_t node;
pcell_t clock, shift;
int err;
const struct ofw_compat_data * cd;
sc = device_get_softc(dev);
if (!ofw_bus_status_okay(dev))
return (ENXIO);
cd = ofw_bus_search_compatible(dev, compat_data);
if (cd->ocd_data == (uintptr_t)NULL)
return (ENXIO);
sc->sc_class = (struct uart_class *)cd->ocd_data;
node = ofw_bus_get_node(dev);
if ((err = uart_fdt_get_clock(node, &clock)) != 0)
return (err);
uart_fdt_get_shift(node, &shift);
return (uart_bus_probe(dev, (int)shift, (int)clock, 0, 0));
}
DRIVER_MODULE(uart, simplebus, uart_fdt_driver, uart_devclass, 0, 0);