freebsd-dev/sys/arm/samsung/exynos/exynos_uart.c
Andrew Turner 405ada37fb Add support for the uart classes to set their default register shift value.
This is needed with the pl011 driver. Before this change it would default
to a shift of 0, however the hardware places the registers at 4-byte
addresses meaning the value should be 2.

This patch fixes this for the pl011 when configured using the fdt. The
other drivers have a default value of 0 to keep this a no-op.

MFC after:	1 week
2015-04-11 17:16:23 +00:00

391 lines
8.9 KiB
C

/*
* Copyright (c) 2003 Marcel Moolenaar
* Copyright (c) 2007-2009 Andrew Turner
* Copyright (c) 2013 Ruslan Bukin <br@bsdpad.com>
* 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 <sys/conf.h>
#include <sys/cons.h>
#include <sys/tty.h>
#include <sys/rman.h>
#include <machine/bus.h>
#include <machine/intr.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 <arm/samsung/exynos/exynos_uart.h>
#include "uart_if.h"
#define DEF_CLK 100000000
static int sscomspeed(long, long);
static int exynos4210_uart_param(struct uart_bas *, int, int, int, int);
/*
* Low-level UART interface.
*/
static int exynos4210_probe(struct uart_bas *bas);
static void exynos4210_init(struct uart_bas *bas, int, int, int, int);
static void exynos4210_term(struct uart_bas *bas);
static void exynos4210_putc(struct uart_bas *bas, int);
static int exynos4210_rxready(struct uart_bas *bas);
static int exynos4210_getc(struct uart_bas *bas, struct mtx *mtx);
extern SLIST_HEAD(uart_devinfo_list, uart_devinfo) uart_sysdevs;
static int
sscomspeed(long speed, long frequency)
{
int x;
if (speed <= 0 || frequency <= 0)
return (-1);
x = (frequency / 16) / speed;
return (x-1);
}
static int
exynos4210_uart_param(struct uart_bas *bas, int baudrate, int databits,
int stopbits, int parity)
{
int brd, ulcon;
ulcon = 0;
switch(databits) {
case 5:
ulcon |= ULCON_LENGTH_5;
break;
case 6:
ulcon |= ULCON_LENGTH_6;
break;
case 7:
ulcon |= ULCON_LENGTH_7;
break;
case 8:
ulcon |= ULCON_LENGTH_8;
break;
default:
return (EINVAL);
}
switch (parity) {
case UART_PARITY_NONE:
ulcon |= ULCON_PARITY_NONE;
break;
case UART_PARITY_ODD:
ulcon |= ULCON_PARITY_ODD;
break;
case UART_PARITY_EVEN:
ulcon |= ULCON_PARITY_EVEN;
break;
case UART_PARITY_MARK:
case UART_PARITY_SPACE:
default:
return (EINVAL);
}
if (stopbits == 2)
ulcon |= ULCON_STOP;
uart_setreg(bas, SSCOM_ULCON, ulcon);
brd = sscomspeed(baudrate, bas->rclk);
uart_setreg(bas, SSCOM_UBRDIV, brd);
return (0);
}
struct uart_ops uart_exynos4210_ops = {
.probe = exynos4210_probe,
.init = exynos4210_init,
.term = exynos4210_term,
.putc = exynos4210_putc,
.rxready = exynos4210_rxready,
.getc = exynos4210_getc,
};
static int
exynos4210_probe(struct uart_bas *bas)
{
return (0);
}
static void
exynos4210_init(struct uart_bas *bas, int baudrate, int databits, int stopbits,
int parity)
{
if (bas->rclk == 0)
bas->rclk = DEF_CLK;
KASSERT(bas->rclk != 0, ("exynos4210_init: Invalid rclk"));
uart_setreg(bas, SSCOM_UCON, 0);
uart_setreg(bas, SSCOM_UFCON,
UFCON_TXTRIGGER_8 | UFCON_RXTRIGGER_8 |
UFCON_TXFIFO_RESET | UFCON_RXFIFO_RESET |
UFCON_FIFO_ENABLE);
exynos4210_uart_param(bas, baudrate, databits, stopbits, parity);
/* Enable UART. */
uart_setreg(bas, SSCOM_UCON, UCON_TXMODE_INT | UCON_RXMODE_INT |
UCON_TOINT);
uart_setreg(bas, SSCOM_UMCON, UMCON_RTS);
}
static void
exynos4210_term(struct uart_bas *bas)
{
/* XXX */
}
static void
exynos4210_putc(struct uart_bas *bas, int c)
{
while ((bus_space_read_4(bas->bst, bas->bsh, SSCOM_UFSTAT) &
UFSTAT_TXFULL) == UFSTAT_TXFULL)
continue;
uart_setreg(bas, SSCOM_UTXH, c);
}
static int
exynos4210_rxready(struct uart_bas *bas)
{
return ((uart_getreg(bas, SSCOM_UTRSTAT) & UTRSTAT_RXREADY) ==
UTRSTAT_RXREADY);
}
static int
exynos4210_getc(struct uart_bas *bas, struct mtx *mtx)
{
int utrstat;
utrstat = bus_space_read_1(bas->bst, bas->bsh, SSCOM_UTRSTAT);
while (!(utrstat & UTRSTAT_RXREADY)) {
utrstat = bus_space_read_1(bas->bst, bas->bsh, SSCOM_UTRSTAT);
continue;
}
return (bus_space_read_1(bas->bst, bas->bsh, SSCOM_URXH));
}
static int exynos4210_bus_probe(struct uart_softc *sc);
static int exynos4210_bus_attach(struct uart_softc *sc);
static int exynos4210_bus_flush(struct uart_softc *, int);
static int exynos4210_bus_getsig(struct uart_softc *);
static int exynos4210_bus_ioctl(struct uart_softc *, int, intptr_t);
static int exynos4210_bus_ipend(struct uart_softc *);
static int exynos4210_bus_param(struct uart_softc *, int, int, int, int);
static int exynos4210_bus_receive(struct uart_softc *);
static int exynos4210_bus_setsig(struct uart_softc *, int);
static int exynos4210_bus_transmit(struct uart_softc *);
static kobj_method_t exynos4210_methods[] = {
KOBJMETHOD(uart_probe, exynos4210_bus_probe),
KOBJMETHOD(uart_attach, exynos4210_bus_attach),
KOBJMETHOD(uart_flush, exynos4210_bus_flush),
KOBJMETHOD(uart_getsig, exynos4210_bus_getsig),
KOBJMETHOD(uart_ioctl, exynos4210_bus_ioctl),
KOBJMETHOD(uart_ipend, exynos4210_bus_ipend),
KOBJMETHOD(uart_param, exynos4210_bus_param),
KOBJMETHOD(uart_receive, exynos4210_bus_receive),
KOBJMETHOD(uart_setsig, exynos4210_bus_setsig),
KOBJMETHOD(uart_transmit, exynos4210_bus_transmit),
{0, 0 }
};
int
exynos4210_bus_probe(struct uart_softc *sc)
{
sc->sc_txfifosz = 16;
sc->sc_rxfifosz = 16;
return (0);
}
static int
exynos4210_bus_attach(struct uart_softc *sc)
{
sc->sc_hwiflow = 0;
sc->sc_hwoflow = 0;
return (0);
}
static int
exynos4210_bus_transmit(struct uart_softc *sc)
{
int i;
int reg;
uart_lock(sc->sc_hwmtx);
for (i = 0; i < sc->sc_txdatasz; i++) {
exynos4210_putc(&sc->sc_bas, sc->sc_txbuf[i]);
uart_barrier(&sc->sc_bas);
}
sc->sc_txbusy = 1;
uart_unlock(sc->sc_hwmtx);
/* unmask TX interrupt */
reg = bus_space_read_4(sc->sc_bas.bst, sc->sc_bas.bsh, SSCOM_UINTM);
reg &= ~(1 << 2);
bus_space_write_4(sc->sc_bas.bst, sc->sc_bas.bsh, SSCOM_UINTM, reg);
return (0);
}
static int
exynos4210_bus_setsig(struct uart_softc *sc, int sig)
{
return (0);
}
static int
exynos4210_bus_receive(struct uart_softc *sc)
{
struct uart_bas *bas;
bas = &sc->sc_bas;
while (bus_space_read_4(bas->bst, bas->bsh,
SSCOM_UFSTAT) & UFSTAT_RXCOUNT)
uart_rx_put(sc, uart_getreg(&sc->sc_bas, SSCOM_URXH));
return (0);
}
static int
exynos4210_bus_param(struct uart_softc *sc, int baudrate, int databits,
int stopbits, int parity)
{
int error;
if (sc->sc_bas.rclk == 0)
sc->sc_bas.rclk = DEF_CLK;
KASSERT(sc->sc_bas.rclk != 0, ("exynos4210_init: Invalid rclk"));
uart_lock(sc->sc_hwmtx);
error = exynos4210_uart_param(&sc->sc_bas, baudrate, databits, stopbits,
parity);
uart_unlock(sc->sc_hwmtx);
return (error);
}
static int
exynos4210_bus_ipend(struct uart_softc *sc)
{
uint32_t ints;
uint32_t txempty, rxready;
int reg;
int ipend;
uart_lock(sc->sc_hwmtx);
ints = bus_space_read_4(sc->sc_bas.bst, sc->sc_bas.bsh, SSCOM_UINTP);
bus_space_write_4(sc->sc_bas.bst, sc->sc_bas.bsh, SSCOM_UINTP, ints);
txempty = (1 << 2);
rxready = (1 << 0);
ipend = 0;
if ((ints & txempty) > 0) {
if (sc->sc_txbusy != 0)
ipend |= SER_INT_TXIDLE;
/* mask TX interrupt */
reg = bus_space_read_4(sc->sc_bas.bst, sc->sc_bas.bsh,
SSCOM_UINTM);
reg |= (1 << 2);
bus_space_write_4(sc->sc_bas.bst, sc->sc_bas.bsh,
SSCOM_UINTM, reg);
}
if ((ints & rxready) > 0) {
ipend |= SER_INT_RXREADY;
}
uart_unlock(sc->sc_hwmtx);
return (ipend);
}
static int
exynos4210_bus_flush(struct uart_softc *sc, int what)
{
return (0);
}
static int
exynos4210_bus_getsig(struct uart_softc *sc)
{
return (0);
}
static int
exynos4210_bus_ioctl(struct uart_softc *sc, int request, intptr_t data)
{
return (EINVAL);
}
static struct uart_class uart_exynos4210_class = {
"exynos4210 class",
exynos4210_methods,
1,
.uc_ops = &uart_exynos4210_ops,
.uc_range = 8,
.uc_rclk = 0,
.uc_rshift = 0
};
static struct ofw_compat_data compat_data[] = {
{"exynos", (uintptr_t)&uart_exynos4210_class},
{NULL, (uintptr_t)NULL},
};
UART_FDT_CLASS_AND_DEVICE(compat_data);