freebsd-nq/sys/dev/uart/uart_dev_z8530.c
Marcel Moolenaar a24d2e121e In z8530_divisor() return 0 if the calculated divisor is less than 0.
This happens when the baudrate is too high for the given RCLK.
2006-04-04 01:16:16 +00:00

604 lines
13 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.
*/
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/bus.h>
#include <sys/conf.h>
#include <machine/bus.h>
#include <dev/uart/uart.h>
#include <dev/uart/uart_cpu.h>
#include <dev/uart/uart_bus.h>
#include <dev/ic/z8530.h>
#include "uart_if.h"
#define DEFAULT_RCLK 307200
/* Multiplexed I/O. */
static __inline void
uart_setmreg(struct uart_bas *bas, int reg, int val)
{
uart_setreg(bas, REG_CTRL, reg);
uart_barrier(bas);
uart_setreg(bas, REG_CTRL, val);
}
static __inline uint8_t
uart_getmreg(struct uart_bas *bas, int reg)
{
uart_setreg(bas, REG_CTRL, reg);
uart_barrier(bas);
return (uart_getreg(bas, REG_CTRL));
}
static int
z8530_divisor(int rclk, int baudrate)
{
int act_baud, divisor, error;
if (baudrate == 0)
return (0);
divisor = (rclk + baudrate) / (baudrate << 1) - 2;
if (divisor < 0 || divisor >= 65536)
return (0);
act_baud = rclk / 2 / (divisor + 2);
/* 10 times error in percent: */
error = ((act_baud - baudrate) * 2000 / baudrate + 1) >> 1;
/* 3.0% maximum error tolerance: */
if (error < -30 || error > 30)
return (0);
return (divisor);
}
static int
z8530_param(struct uart_bas *bas, int baudrate, int databits, int stopbits,
int parity, uint8_t *tpcp)
{
int divisor;
uint8_t mpm, rpc, tpc;
rpc = RPC_RXE;
mpm = MPM_CM16;
tpc = TPC_TXE | (*tpcp & (TPC_DTR | TPC_RTS));
if (databits >= 8) {
rpc |= RPC_RB8;
tpc |= TPC_TB8;
} else if (databits == 7) {
rpc |= RPC_RB7;
tpc |= TPC_TB7;
} else if (databits == 6) {
rpc |= RPC_RB6;
tpc |= TPC_TB6;
} else {
rpc |= RPC_RB5;
tpc |= TPC_TB5;
}
mpm |= (stopbits > 1) ? MPM_SB2 : MPM_SB1;
switch (parity) {
case UART_PARITY_EVEN: mpm |= MPM_PE | MPM_EVEN; break;
case UART_PARITY_NONE: break;
case UART_PARITY_ODD: mpm |= MPM_PE; break;
default: return (EINVAL);
}
/* Set baudrate. */
if (baudrate > 0) {
divisor = z8530_divisor(bas->rclk, baudrate);
if (divisor == 0)
return (EINVAL);
uart_setmreg(bas, WR_TCL, divisor & 0xff);
uart_barrier(bas);
uart_setmreg(bas, WR_TCH, (divisor >> 8) & 0xff);
uart_barrier(bas);
}
uart_setmreg(bas, WR_RPC, rpc);
uart_barrier(bas);
uart_setmreg(bas, WR_MPM, mpm);
uart_barrier(bas);
uart_setmreg(bas, WR_TPC, tpc);
uart_barrier(bas);
*tpcp = tpc;
return (0);
}
static int
z8530_setup(struct uart_bas *bas, int baudrate, int databits, int stopbits,
int parity)
{
uint8_t tpc;
if (bas->rclk == 0)
bas->rclk = DEFAULT_RCLK;
/* Assume we don't need to perform a full hardware reset. */
switch (bas->chan) {
case 1:
uart_setmreg(bas, WR_MIC, MIC_NV | MIC_CRA);
break;
case 2:
uart_setmreg(bas, WR_MIC, MIC_NV | MIC_CRB);
break;
}
uart_barrier(bas);
/* Set clock sources and enable BRG. */
uart_setmreg(bas, WR_CMC, CMC_RC_BRG | CMC_TC_BRG);
uart_setmreg(bas, WR_MCB2, MCB2_PCLK | MCB2_BRGE);
uart_barrier(bas);
/* Set data encoding. */
uart_setmreg(bas, WR_MCB1, MCB1_NRZ);
uart_barrier(bas);
tpc = TPC_DTR | TPC_RTS;
z8530_param(bas, baudrate, databits, stopbits, parity, &tpc);
return (int)tpc;
}
/*
* Low-level UART interface.
*/
static int z8530_probe(struct uart_bas *bas);
static void z8530_init(struct uart_bas *bas, int, int, int, int);
static void z8530_term(struct uart_bas *bas);
static void z8530_putc(struct uart_bas *bas, int);
static int z8530_poll(struct uart_bas *bas);
static int z8530_getc(struct uart_bas *bas, struct mtx *);
struct uart_ops uart_z8530_ops = {
.probe = z8530_probe,
.init = z8530_init,
.term = z8530_term,
.putc = z8530_putc,
.poll = z8530_poll,
.getc = z8530_getc,
};
static int
z8530_probe(struct uart_bas *bas)
{
return (0);
}
static void
z8530_init(struct uart_bas *bas, int baudrate, int databits, int stopbits,
int parity)
{
z8530_setup(bas, baudrate, databits, stopbits, parity);
}
static void
z8530_term(struct uart_bas *bas)
{
}
static void
z8530_putc(struct uart_bas *bas, int c)
{
while (!(uart_getreg(bas, REG_CTRL) & BES_TXE))
;
uart_setreg(bas, REG_DATA, c);
uart_barrier(bas);
}
static int
z8530_poll(struct uart_bas *bas)
{
if (!(uart_getreg(bas, REG_CTRL) & BES_RXA))
return (-1);
return (uart_getreg(bas, REG_DATA));
}
static int
z8530_getc(struct uart_bas *bas, struct mtx *hwmtx)
{
int c;
uart_lock(hwmtx);
while (!(uart_getreg(bas, REG_CTRL) & BES_RXA)) {
uart_unlock(hwmtx);
DELAY(10);
uart_lock(hwmtx);
}
c = uart_getreg(bas, REG_DATA);
uart_unlock(hwmtx);
return (c);
}
/*
* High-level UART interface.
*/
struct z8530_softc {
struct uart_softc base;
uint8_t tpc;
uint8_t txidle;
};
static int z8530_bus_attach(struct uart_softc *);
static int z8530_bus_detach(struct uart_softc *);
static int z8530_bus_flush(struct uart_softc *, int);
static int z8530_bus_getsig(struct uart_softc *);
static int z8530_bus_ioctl(struct uart_softc *, int, intptr_t);
static int z8530_bus_ipend(struct uart_softc *);
static int z8530_bus_param(struct uart_softc *, int, int, int, int);
static int z8530_bus_probe(struct uart_softc *);
static int z8530_bus_receive(struct uart_softc *);
static int z8530_bus_setsig(struct uart_softc *, int);
static int z8530_bus_transmit(struct uart_softc *);
static kobj_method_t z8530_methods[] = {
KOBJMETHOD(uart_attach, z8530_bus_attach),
KOBJMETHOD(uart_detach, z8530_bus_detach),
KOBJMETHOD(uart_flush, z8530_bus_flush),
KOBJMETHOD(uart_getsig, z8530_bus_getsig),
KOBJMETHOD(uart_ioctl, z8530_bus_ioctl),
KOBJMETHOD(uart_ipend, z8530_bus_ipend),
KOBJMETHOD(uart_param, z8530_bus_param),
KOBJMETHOD(uart_probe, z8530_bus_probe),
KOBJMETHOD(uart_receive, z8530_bus_receive),
KOBJMETHOD(uart_setsig, z8530_bus_setsig),
KOBJMETHOD(uart_transmit, z8530_bus_transmit),
{ 0, 0 }
};
struct uart_class uart_z8530_class = {
"z8530 class",
z8530_methods,
sizeof(struct z8530_softc),
.uc_range = 2,
.uc_rclk = DEFAULT_RCLK
};
#define SIGCHG(c, i, s, d) \
if (c) { \
i |= (i & s) ? s : s | d; \
} else { \
i = (i & s) ? (i & ~s) | d : i; \
}
static int
z8530_bus_attach(struct uart_softc *sc)
{
struct z8530_softc *z8530 = (struct z8530_softc*)sc;
struct uart_bas *bas;
struct uart_devinfo *di;
bas = &sc->sc_bas;
if (sc->sc_sysdev != NULL) {
di = sc->sc_sysdev;
z8530->tpc = TPC_DTR|TPC_RTS;
z8530_param(bas, di->baudrate, di->databits, di->stopbits,
di->parity, &z8530->tpc);
} else {
z8530->tpc = z8530_setup(bas, 9600, 8, 1, UART_PARITY_NONE);
z8530->tpc &= ~(TPC_DTR|TPC_RTS);
}
z8530->txidle = 1; /* Report SER_INT_TXIDLE. */
sc->sc_rxfifosz = 3;
sc->sc_txfifosz = 1;
(void)z8530_bus_getsig(sc);
uart_setmreg(bas, WR_IC, IC_BRK | IC_CTS | IC_DCD);
uart_barrier(bas);
uart_setmreg(bas, WR_IDT, IDT_XIE | IDT_TIE | IDT_RIA);
uart_barrier(bas);
uart_setmreg(bas, WR_IV, 0);
uart_barrier(bas);
uart_setmreg(bas, WR_TPC, z8530->tpc);
uart_barrier(bas);
uart_setmreg(bas, WR_MIC, MIC_NV | MIC_MIE);
uart_barrier(bas);
return (0);
}
static int
z8530_bus_detach(struct uart_softc *sc)
{
return (0);
}
static int
z8530_bus_flush(struct uart_softc *sc, int what)
{
return (0);
}
static int
z8530_bus_getsig(struct uart_softc *sc)
{
uint32_t new, old, sig;
uint8_t bes;
do {
old = sc->sc_hwsig;
sig = old;
uart_lock(sc->sc_hwmtx);
bes = uart_getmreg(&sc->sc_bas, RR_BES);
uart_unlock(sc->sc_hwmtx);
SIGCHG(bes & BES_CTS, sig, SER_CTS, SER_DCTS);
SIGCHG(bes & BES_DCD, sig, SER_DCD, SER_DDCD);
SIGCHG(bes & BES_SYNC, sig, SER_DSR, SER_DDSR);
new = sig & ~SER_MASK_DELTA;
} while (!atomic_cmpset_32(&sc->sc_hwsig, old, new));
return (sig);
}
static int
z8530_bus_ioctl(struct uart_softc *sc, int request, intptr_t data)
{
struct z8530_softc *z8530 = (struct z8530_softc*)sc;
struct uart_bas *bas;
int error;
bas = &sc->sc_bas;
error = 0;
uart_lock(sc->sc_hwmtx);
switch (request) {
case UART_IOCTL_BREAK:
if (data)
z8530->tpc |= TPC_BRK;
else
z8530->tpc &= ~TPC_BRK;
uart_setmreg(bas, WR_TPC, z8530->tpc);
uart_barrier(bas);
break;
default:
error = EINVAL;
break;
}
uart_unlock(sc->sc_hwmtx);
return (error);
}
static int
z8530_bus_ipend(struct uart_softc *sc)
{
struct z8530_softc *z8530 = (struct z8530_softc*)sc;
struct uart_bas *bas;
int ipend;
uint32_t sig;
uint8_t bes, ip, iv, src;
bas = &sc->sc_bas;
ipend = 0;
uart_lock(sc->sc_hwmtx);
switch (bas->chan) {
case 1:
ip = uart_getmreg(bas, RR_IP);
break;
case 2: /* XXX hack!!! */
iv = uart_getmreg(bas, RR_IV) & 0x0E;
switch (iv) {
case IV_TEB: ip = IP_TIA; break;
case IV_XSB: ip = IP_SIA; break;
case IV_RAB: ip = IP_RIA; break;
default: ip = 0; break;
}
break;
default:
ip = 0;
break;
}
if (ip & IP_RIA)
ipend |= SER_INT_RXREADY;
if (ip & IP_TIA) {
uart_setreg(bas, REG_CTRL, CR_RSTTXI);
uart_barrier(bas);
if (z8530->txidle) {
ipend |= SER_INT_TXIDLE;
z8530->txidle = 0; /* Mask SER_INT_TXIDLE. */
}
}
if (ip & IP_SIA) {
uart_setreg(bas, REG_CTRL, CR_RSTXSI);
uart_barrier(bas);
bes = uart_getmreg(bas, RR_BES);
if (bes & BES_BRK)
ipend |= SER_INT_BREAK;
sig = sc->sc_hwsig;
SIGCHG(bes & BES_CTS, sig, SER_CTS, SER_DCTS);
SIGCHG(bes & BES_DCD, sig, SER_DCD, SER_DDCD);
SIGCHG(bes & BES_SYNC, sig, SER_DSR, SER_DDSR);
if (sig & SER_MASK_DELTA)
ipend |= SER_INT_SIGCHG;
src = uart_getmreg(bas, RR_SRC);
if (src & SRC_OVR) {
uart_setreg(bas, REG_CTRL, CR_RSTERR);
uart_barrier(bas);
ipend |= SER_INT_OVERRUN;
}
}
if (ipend) {
uart_setreg(bas, REG_CTRL, CR_RSTIUS);
uart_barrier(bas);
}
uart_unlock(sc->sc_hwmtx);
return (ipend);
}
static int
z8530_bus_param(struct uart_softc *sc, int baudrate, int databits,
int stopbits, int parity)
{
struct z8530_softc *z8530 = (struct z8530_softc*)sc;
int error;
uart_lock(sc->sc_hwmtx);
error = z8530_param(&sc->sc_bas, baudrate, databits, stopbits, parity,
&z8530->tpc);
uart_unlock(sc->sc_hwmtx);
return (error);
}
static int
z8530_bus_probe(struct uart_softc *sc)
{
char buf[80];
int error;
char ch;
error = z8530_probe(&sc->sc_bas);
if (error)
return (error);
ch = sc->sc_bas.chan - 1 + 'A';
snprintf(buf, sizeof(buf), "z8530, channel %c", ch);
device_set_desc_copy(sc->sc_dev, buf);
return (0);
}
static int
z8530_bus_receive(struct uart_softc *sc)
{
struct uart_bas *bas;
int xc;
uint8_t bes, src;
bas = &sc->sc_bas;
uart_lock(sc->sc_hwmtx);
bes = uart_getmreg(bas, RR_BES);
while (bes & BES_RXA) {
if (uart_rx_full(sc)) {
sc->sc_rxbuf[sc->sc_rxput] = UART_STAT_OVERRUN;
break;
}
xc = uart_getreg(bas, REG_DATA);
uart_barrier(bas);
src = uart_getmreg(bas, RR_SRC);
if (src & SRC_FE)
xc |= UART_STAT_FRAMERR;
if (src & SRC_PE)
xc |= UART_STAT_PARERR;
if (src & SRC_OVR)
xc |= UART_STAT_OVERRUN;
uart_rx_put(sc, xc);
if (src & (SRC_FE | SRC_PE | SRC_OVR)) {
uart_setreg(bas, REG_CTRL, CR_RSTERR);
uart_barrier(bas);
}
bes = uart_getmreg(bas, RR_BES);
}
/* Discard everything left in the Rx FIFO. */
while (bes & BES_RXA) {
(void)uart_getreg(bas, REG_DATA);
uart_barrier(bas);
src = uart_getmreg(bas, RR_SRC);
if (src & (SRC_FE | SRC_PE | SRC_OVR)) {
uart_setreg(bas, REG_CTRL, CR_RSTERR);
uart_barrier(bas);
}
bes = uart_getmreg(bas, RR_BES);
}
uart_unlock(sc->sc_hwmtx);
return (0);
}
static int
z8530_bus_setsig(struct uart_softc *sc, int sig)
{
struct z8530_softc *z8530 = (struct z8530_softc*)sc;
struct uart_bas *bas;
uint32_t new, old;
bas = &sc->sc_bas;
do {
old = sc->sc_hwsig;
new = old;
if (sig & SER_DDTR) {
SIGCHG(sig & SER_DTR, new, SER_DTR,
SER_DDTR);
}
if (sig & SER_DRTS) {
SIGCHG(sig & SER_RTS, new, SER_RTS,
SER_DRTS);
}
} while (!atomic_cmpset_32(&sc->sc_hwsig, old, new));
uart_lock(sc->sc_hwmtx);
if (new & SER_DTR)
z8530->tpc |= TPC_DTR;
else
z8530->tpc &= ~TPC_DTR;
if (new & SER_RTS)
z8530->tpc |= TPC_RTS;
else
z8530->tpc &= ~TPC_RTS;
uart_setmreg(bas, WR_TPC, z8530->tpc);
uart_barrier(bas);
uart_unlock(sc->sc_hwmtx);
return (0);
}
static int
z8530_bus_transmit(struct uart_softc *sc)
{
struct z8530_softc *z8530 = (struct z8530_softc*)sc;
struct uart_bas *bas;
bas = &sc->sc_bas;
uart_lock(sc->sc_hwmtx);
while (!(uart_getmreg(bas, RR_BES) & BES_TXE))
;
uart_setreg(bas, REG_DATA, sc->sc_txbuf[0]);
uart_barrier(bas);
sc->sc_txbusy = 1;
z8530->txidle = 1; /* Report SER_INT_TXIDLE again. */
uart_unlock(sc->sc_hwmtx);
return (0);
}