freebsd-skq/sys/mips/mediatek/uart_dev_mtk_ns8250.c
Stanislav Galabov dc0996af4e Initial import of Ralink/Mediatek MIPS SoC support #4
UART drivers.

- uart_dev_mtk.[ch] are the old-style Mediatek/Ralink-specific UART driver
  as also found in sys/mips/rt305x/uart_dev_rt305x.c, with minor improvements
  and FDT attachment enabled for the appropriate SoCs.
- uart_dev_mtk_ns8250.c is the new-style ns16550a-compatible UART driver
  found in newer Mediatek SoCs. It uses the uart_dev_ns8250.c driver
  indirectly and is basically just a wrapper around it and only overrides its
  probe method.
  The reason I am not using the uart_dev_ns8250.c driver directly is because
  I have some code that does UART clock detection before initializing the
  UART, so that we don't need to hard-code the UART clock frequency in the
  dts files for each board.

Approved by:	adrian (mentor)
Sponsored by:	Smartcom - Bulgaria AD
Differential Revision:	https://reviews.freebsd.org/D5840
2016-04-07 11:16:32 +00:00

114 lines
3.5 KiB
C

/*-
* Copyright (c) 2013 Ian Lepore
* 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 "opt_platform.h"
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/bus.h>
#include <sys/conf.h>
#include <sys/kernel.h>
#include <sys/sysctl.h>
#include <machine/bus.h>
#include <mips/mediatek/mtk_soc.h>
#include <mips/mediatek/mtk_sysctl.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_cpu.h>
#include <dev/uart/uart_cpu_fdt.h>
#include <dev/uart/uart_bus.h>
#include <dev/uart/uart_dev_ns8250.h>
#include "uart_if.h"
/*
* High-level UART interface.
*/
static struct uart_class uart_mtk_ns8250_class;
static int mtk_ns8250_bus_probe(struct uart_softc *);
static kobj_method_t mtk_ns8250_methods[] = {
KOBJMETHOD(uart_probe, mtk_ns8250_bus_probe),
KOBJMETHOD(uart_attach, ns8250_bus_attach),
KOBJMETHOD(uart_detach, ns8250_bus_detach),
KOBJMETHOD(uart_flush, ns8250_bus_flush),
KOBJMETHOD(uart_getsig, ns8250_bus_getsig),
KOBJMETHOD(uart_ioctl, ns8250_bus_ioctl),
KOBJMETHOD(uart_ipend, ns8250_bus_ipend),
KOBJMETHOD(uart_param, ns8250_bus_param),
KOBJMETHOD(uart_receive, ns8250_bus_receive),
KOBJMETHOD(uart_setsig, ns8250_bus_setsig),
KOBJMETHOD(uart_transmit, ns8250_bus_transmit),
KOBJMETHOD_END
};
static struct uart_class uart_mtk_ns8250_class = {
"mtk8250",
mtk_ns8250_methods,
sizeof(struct ns8250_softc),
.uc_ops = &uart_ns8250_ops,
.uc_range = 1, /* use hinted range */
.uc_rclk = 0,
.uc_rshift = 2
};
static struct ofw_compat_data compat_data[] = {
{ "mtk,ns16550a", (uintptr_t)&uart_mtk_ns8250_class },
{ "ns16550a", (uintptr_t)&uart_mtk_ns8250_class },
{ NULL, (uintptr_t)NULL },
};
UART_FDT_CLASS_AND_DEVICE(compat_data);
static int
mtk_ns8250_bus_probe(struct uart_softc *sc)
{
int status;
if (!ofw_bus_status_okay(sc->sc_dev))
return (ENXIO);
if (ofw_bus_search_compatible(sc->sc_dev, compat_data)->ocd_data ==
(uintptr_t)NULL)
return (ENXIO);
sc->sc_bas.rclk = mtk_soc_get_uartclk();
status = ns8250_bus_probe(sc);
if (status == 0)
device_set_desc(sc->sc_dev, "MTK UART Controller (ns16550a)");
return (status);
}