/* $NetBSD: zs.c,v 1.25 2014/06/08 10:40:52 he Exp $ */
/*-
* Copyright (c) 1996, 2000 The NetBSD Foundation, Inc.
* All rights reserved.
*
* This code is derived from software contributed to The NetBSD Foundation
* by Gordon W. Ross and Wayne Knowles
*
* 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 NETBSD FOUNDATION, INC. 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 FOUNDATION 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.
*/
/*
* Zilog Z8530 Dual UART driver (machine-dependent part)
*
* Runs two serial lines per chip using slave drivers.
* Plain tty/async lines use the zs_async slave.
*/
#include <sys/cdefs.h>
__KERNEL_RCSID(0, "$NetBSD: zs.c,v 1.25 2014/06/08 10:40:52 he Exp $");
#include "opt_ddb.h"
#include "opt_kgdb.h"
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/conf.h>
#include <sys/device.h>
#include <sys/file.h>
#include <sys/ioctl.h>
#include <sys/kernel.h>
#include <sys/proc.h>
#include <sys/tty.h>
#include <sys/time.h>
#include <sys/syslog.h>
#include <sys/cpu.h>
#include <sys/intr.h>
#include <machine/mainboard.h>
#include <machine/autoconf.h>
#include <machine/prom.h>
#include <machine/z8530var.h>
#include <dev/cons.h>
#include <dev/ic/z8530reg.h>
#include "ioconf.h"
#include "zsc.h" /* NZSC */
#define NZS NZSC
/* Make life easier for the initialized arrays here. */
#if NZS < 2
#undef NZS
#define NZS 2
#endif
/*
* Some warts needed by z8530tty.c -
* The default parity REALLY needs to be the same as the PROM uses,
* or you can not see messages done with printf during boot-up...
*/
int zs_def_cflag = (CREAD | CS8 | HUPCL);
#define PCLK 10000000 /* PCLK pin input clock rate */
#ifndef ZS_DEFSPEED
#define ZS_DEFSPEED 9600
#endif
/*
* Define interrupt levels.
*/
#define ZSHARD_PRI 64
/* Register recovery time is 3.5 to 4 PCLK Cycles */
#define ZS_RECOVERY 1 /* 1us = 10 PCLK Cycles */
#define ZS_DELAY() delay(ZS_RECOVERY)
/* The layout of this is hardware-dependent (padding, order). */
struct zschan {
uint8_t pad1[3];
volatile uint8_t zc_csr; /* ctrl,status, and indirect access */
uint8_t pad2[3];
volatile uint8_t zc_data; /* data */
};
struct zsdevice {
/* Yes, they are backwards. */
struct zschan zs_chan_b;
struct zschan zs_chan_a;
};
/* Return the byte offset of element within a structure */
#define OFFSET(struct_def, el) ((size_t)&((struct_def *)0)->el)
#define ZS_CHAN_A OFFSET(struct zsdevice, zs_chan_a)
#define ZS_CHAN_B OFFSET(struct zsdevice, zs_chan_b)
#define ZS_REG_CSR OFFSET(struct zschan, zc_csr)
#define ZS_REG_DATA OFFSET(struct zschan, zc_data)
static int zs_chan_offset[] = {ZS_CHAN_A, ZS_CHAN_B};
/* Flags from cninit() */
static int zs_hwflags[NZS][2];
/* Default speed for all channels */
static int zs_defspeed = ZS_DEFSPEED;
static volatile int zssoftpending;
static uint8_t zs_init_reg[16] = {
0, /* 0: CMD (reset, etc.) */
0, /* 1: No interrupts yet. */
ZSHARD_PRI, /* 2: IVECT */
ZSWR3_RX_8 | ZSWR3_RX_ENABLE,
ZSWR4_CLK_X16 | ZSWR4_ONESB,
ZSWR5_TX_8 | ZSWR5_TX_ENABLE,
0, /* 6: TXSYNC/SYNCLO */
0, /* 7: RXSYNC/SYNCHI */
0, /* 8: alias for data port */
ZSWR9_MASTER_IE,
0, /*10: Misc. TX/RX control bits */
ZSWR11_TXCLK_BAUD | ZSWR11_RXCLK_BAUD | ZSWR11_TRXC_OUT_ENA,
BPS_TO_TCONST(PCLK/16, ZS_DEFSPEED), /*12: BAUDLO (default=9600) */
0, /*13: BAUDHI (default=9600) */
ZSWR14_BAUD_ENA | ZSWR14_BAUD_FROM_PCLK,
ZSWR15_BREAK_IE,
};
/****************************************************************
* Autoconfig
****************************************************************/
/* Definition of the driver for autoconfig. */
static int zs_match(device_t, cfdata_t, void *);
static void zs_attach(device_t, device_t, void *);
static int zs_print(void *, const char *name);
CFATTACH_DECL_NEW(zsc, sizeof(struct zsc_softc),
zs_match, zs_attach, NULL, NULL);
static int zshard(void *);
void zssoft(void *);
static int zs_get_speed(struct zs_chanstate *);
struct zschan *zs_get_chan_addr(int zs_unit, int channel);
int zs_getc(void *);
void zs_putc(void *, int);
/*
* Is the zs chip present?
*/
static int
zs_match(device_t parent, cfdata_t cf, void *aux)
{
struct confargs *ca = aux;
void *va;
if (strcmp(ca->ca_name, "zsc"))
return 0;
va = (void *)cf->cf_addr;
/* This returns -1 on a fault (bus error). */
if (badaddr(va, 1))
return 0;
return 1;
}
/*
* Attach a found zs.
*
* Match slave number to zs unit number, so that misconfiguration will
* not set up the keyboard as ttya, etc.
*/
static void
zs_attach(device_t parent, device_t self, void *aux)
{
struct zsc_softc *zsc = device_private(self);
struct confargs *ca = aux;
struct zsc_attach_args zsc_args;
struct zs_chanstate *cs;
struct zs_channel *ch;
int zs_unit, channel, s;
zsc->zsc_dev = self;
zsc->zsc_bustag = ca->ca_bustag;
if (bus_space_map(ca->ca_bustag, ca->ca_addr,
sizeof(struct zsdevice),
BUS_SPACE_MAP_LINEAR,
&zsc->zsc_base) != 0) {
aprint_error(": cannot map registers\n");
return;
}
zs_unit = device_unit(self);
aprint_normal("\n");
/*
* Initialize software state for each channel.
*/
for (channel = 0; channel < 2; channel++) {
zsc_args.channel = channel;
zsc_args.hwflags = zs_hwflags[zs_unit][channel];
ch = &zsc->zsc_cs_store[channel];
cs = zsc->zsc_cs[channel] = (struct zs_chanstate *)ch;
zs_lock_init(cs);
cs->cs_reg_csr = NULL;
cs->cs_reg_data = NULL;
cs->cs_channel = channel;
cs->cs_private = NULL;
cs->cs_ops = &zsops_null;
cs->cs_brg_clk = PCLK / 16;
if (bus_space_subregion(ca->ca_bustag, zsc->zsc_base,
zs_chan_offset[channel],
sizeof(struct zschan),
&ch->cs_regs) != 0) {
aprint_error_dev(self, ": cannot map regs\n");
return;
}
ch->cs_bustag = ca->ca_bustag;
memcpy(cs->cs_creg, zs_init_reg, 16);
memcpy(cs->cs_preg, zs_init_reg, 16);
if (zsc_args.hwflags & ZS_HWFLAG_CONSOLE)
cs->cs_defspeed = zs_get_speed(cs);
else
cs->cs_defspeed = zs_defspeed;
cs->cs_defcflag = zs_def_cflag;
/* Make these correspond to cs_defcflag (-crtscts) */
cs->cs_rr0_dcd = ZSRR0_DCD;
cs->cs_rr0_cts = 0;
cs->cs_wr5_dtr = ZSWR5_DTR | ZSWR5_RTS;
cs->cs_wr5_rts = 0;
/*
* Clear the master interrupt enable.
* The INTENA is common to both channels,
* so just do it on the A channel.
*/
if (channel == 0) {
zs_write_reg(cs, 9, 0);
}
/*
* Look for a child driver for this channel.
* The child attach will setup the hardware.
*/
if (!config_found(self, (void *)&zsc_args, zs_print)) {
/* No sub-driver. Just reset it. */
uint8_t reset = (channel == 0) ?
ZSWR9_A_RESET : ZSWR9_B_RESET;
s = splhigh();
zs_write_reg(cs, 9, reset);
splx(s);
}
}
zsc->sc_si = softint_establish(SOFTINT_SERIAL, zssoft, zsc);
bus_intr_establish(zsc->zsc_bustag, SYS_INTR_SCC0, 0, 0, zshard, NULL);
evcnt_attach_dynamic(&zsc->zs_intrcnt, EVCNT_TYPE_INTR, NULL,
device_xname(self), "intr");
/*
* Set the master interrupt enable and interrupt vector.
* (common to both channels, do it on A)
*/
cs = zsc->zsc_cs[0];
s = splhigh();
/* interrupt vector */
zs_write_reg(cs, 2, zs_init_reg[2]);
/* master interrupt control (enable) */
zs_write_reg(cs, 9, zs_init_reg[9]);
splx(s);
}
static int
zs_print(void *aux, const char *name)
{
struct zsc_attach_args *args = aux;
if (name != NULL)
aprint_normal("%s: ", name);
if (args->channel != -1)
aprint_normal(" channel %d", args->channel);
return UNCONF;
}
/*
* Our ZS chips all share a common, autovectored interrupt,
* so we have to look at all of them on each interrupt.
*/
static int
zshard(void *arg)
{
struct zsc_softc *zsc;
int unit, rval, softreq;
rval = 0;
for (unit = 0; unit < zsc_cd.cd_ndevs; unit++) {
zsc = device_lookup_private(&zsc_cd, unit);
if (zsc == NULL)
continue;
rval |= zsc_intr_hard(zsc);
softreq = zsc->zsc_cs[0]->cs_softreq;
softreq |= zsc->zsc_cs[1]->cs_softreq;
if (softreq && (zssoftpending == 0)) {
zssoftpending = 1;
softint_schedule(zsc->sc_si);
}
zsc->zs_intrcnt.ev_count++;
}
return rval;
}
/*
* Similar scheme as for zshard (look at all of them)
*/
void
zssoft(void *arg)
{
struct zsc_softc *zsc;
int s, unit;
/* This is not the only ISR on this IPL. */
if (zssoftpending == 0)
return;
/*
* The soft intr. bit will be set by zshard only if
* the variable zssoftpending is zero. The order of
* these next two statements prevents our clearing
* the soft intr bit just after zshard has set it.
*/
/*isr_soft_clear(ZSSOFT_PRI);*/
zssoftpending = 0;
/* Make sure we call the tty layer at spltty. */
s = spltty();
for (unit = 0; unit < zsc_cd.cd_ndevs; unit++) {
zsc = device_lookup_private(&zsc_cd, unit);
if (zsc == NULL)
continue;
(void)zsc_intr_soft(zsc);
}
splx(s);
return;
}
/*
* Compute the current baud rate given a ZS channel.
*/
static int
zs_get_speed(struct zs_chanstate *cs)
{
int tconst;
tconst = zs_read_reg(cs, 12);
tconst |= zs_read_reg(cs, 13) << 8;
return (TCONST_TO_BPS(cs->cs_brg_clk, tconst));
}
/*
* MD functions for setting the baud rate and control modes.
*/
int
zs_set_speed(struct zs_chanstate *cs, int bps)
{
int tconst;
#if 0
int real_bps;
#endif
#if 0
while (!(zs_read_csr(cs) & ZSRR0_TX_READY))
{/*nop*/}
#endif
/* Wait for transmit buffer to empty */
if (bps == 0) {
return (0);
}
#ifdef DIAGNOSTIC
if (cs->cs_brg_clk == 0)
panic("zs_set_speed");
#endif
tconst = BPS_TO_TCONST(cs->cs_brg_clk, bps);
if (tconst < 0)
return (EINVAL);
#if 0
/* Convert back to make sure we can do it. */
real_bps = TCONST_TO_BPS(cs->cs_brg_clk, tconst);
/* XXX - Allow some tolerance here? */
if (real_bps != bps)
return (EINVAL);
#endif
cs->cs_preg[12] = tconst;
cs->cs_preg[13] = tconst >> 8;
/* Caller will stuff the pending registers. */
return (0);
}
int
zs_set_modes(struct zs_chanstate *cs, int cflag)
{
int s;
/*
* Output hardware flow control on the chip is horrendous:
* if carrier detect drops, the receiver is disabled, and if
* CTS drops, the transmitter is stoped IN MID CHARACTER!
* Therefore, NEVER set the HFC bit, and instead use the
* status interrupt to detect CTS changes.
*/
s = splzs();
cs->cs_rr0_pps = 0;
if ((cflag & (CLOCAL | MDMBUF)) != 0) {
cs->cs_rr0_dcd = 0;
if ((cflag & MDMBUF) == 0)
cs->cs_rr0_pps = ZSRR0_DCD;
} else
cs->cs_rr0_dcd = ZSRR0_DCD;
if ((cflag & CRTSCTS) != 0) {
cs->cs_wr5_dtr = ZSWR5_DTR;
cs->cs_wr5_rts = ZSWR5_RTS;
cs->cs_rr0_cts = ZSRR0_CTS;
} else if ((cflag & MDMBUF) != 0) {
cs->cs_wr5_dtr = 0;
cs->cs_wr5_rts = ZSWR5_DTR;
cs->cs_rr0_cts = ZSRR0_DCD;
} else {
cs->cs_wr5_dtr = ZSWR5_DTR | ZSWR5_RTS;
cs->cs_wr5_rts = 0;
cs->cs_rr0_cts = 0;
}
splx(s);
/* Caller will stuff the pending registers. */
return (0);
}
/*
* Read or write the chip with suitable delays.
*/
uint8_t
zs_read_reg(struct zs_chanstate *cs, uint8_t reg)
{
uint8_t val;
struct zs_channel *zsc = (struct zs_channel *)cs;
bus_space_write_1(zsc->cs_bustag, zsc->cs_regs, ZS_REG_CSR, reg);
ZS_DELAY();
val = bus_space_read_1(zsc->cs_bustag, zsc->cs_regs, ZS_REG_CSR);
ZS_DELAY();
return val;
}
void
zs_write_reg(struct zs_chanstate *cs, uint8_t reg, uint8_t val)
{
struct zs_channel *zsc = (struct zs_channel *)cs;
bus_space_write_1(zsc->cs_bustag, zsc->cs_regs, ZS_REG_CSR, reg);
ZS_DELAY();
bus_space_write_1(zsc->cs_bustag, zsc->cs_regs, ZS_REG_CSR, val);
ZS_DELAY();
}
uint8_t
zs_read_csr(struct zs_chanstate *cs)
{
struct zs_channel *zsc = (struct zs_channel *)cs;
uint8_t val;
val = bus_space_read_1(zsc->cs_bustag, zsc->cs_regs, ZS_REG_CSR);
ZS_DELAY();
return val;
}
void
zs_write_csr(struct zs_chanstate *cs, uint8_t val)
{
struct zs_channel *zsc = (struct zs_channel *)cs;
bus_space_write_1(zsc->cs_bustag, zsc->cs_regs, ZS_REG_CSR, val);
ZS_DELAY();
}
uint8_t
zs_read_data(struct zs_chanstate *cs)
{
struct zs_channel *zsc = (struct zs_channel *)cs;
uint8_t val;
val = bus_space_read_1(zsc->cs_bustag, zsc->cs_regs, ZS_REG_DATA);
ZS_DELAY();
return val;
}
void
zs_write_data(struct zs_chanstate *cs, uint8_t val)
{
struct zs_channel *zsc = (struct zs_channel *)cs;
bus_space_write_1(zsc->cs_bustag, zsc->cs_regs, ZS_REG_DATA, val);
ZS_DELAY();
}
void
zs_abort(struct zs_chanstate *cs)
{
#if defined(KGDB)
zskgdb(cs);
#elif defined(DDB)
Debugger();
#endif
}
/*********************************************************/
/* Polled character I/O functions for console and KGDB */
/*********************************************************/
struct zschan *
zs_get_chan_addr(int zs_unit, int channel)
{
struct zsdevice *addr;
struct zschan *zc;
if (zs_unit >= NZS)
return NULL;
addr = (struct zsdevice *) ZS0_ADDR;
if (channel == 0) {
zc = &addr->zs_chan_a;
} else {
zc = &addr->zs_chan_b;
}
return (zc);
}
int
zs_getc(void *arg)
{
volatile struct zschan *zc = arg;
int s, c;
uint8_t rr0;
s = splhigh();
/* Wait for a character to arrive. */
do {
rr0 = zc->zc_csr;
ZS_DELAY();
} while ((rr0 & ZSRR0_RX_READY) == 0);
c = zc->zc_data;
ZS_DELAY();
splx(s);
return (c);
}
/*
* Polled output char.
*/
void
zs_putc(void *arg, int c)
{
volatile struct zschan *zc = arg;
int s;
uint8_t rr0;
s = splhigh();
/* Wait for transmitter to become ready. */
do {
rr0 = zc->zc_csr;
ZS_DELAY();
} while ((rr0 & ZSRR0_TX_READY) == 0);
zc->zc_data = c;
wbflush();
ZS_DELAY();
splx(s);
}
/***************************************************************/
static void zscnprobe(struct consdev *);
static void zscninit(struct consdev *);
static int zscngetc(dev_t);
static void zscnputc(dev_t, int);
static void zscnpollc(dev_t, int);
static int cons_port;
struct consdev consdev_zs = {
zscnprobe,
zscninit,
zscngetc,
zscnputc,
zscnpollc
};
void
zscnprobe(struct consdev *cn)
{
}
void
zscninit(struct consdev *cn)
{
extern const struct cdevsw zstty_cdevsw;
cons_port = prom_getconsole();
cn->cn_dev = makedev(cdevsw_lookup_major(&zstty_cdevsw), cons_port);
cn->cn_pri = CN_REMOTE;
zs_hwflags[0][cons_port] = ZS_HWFLAG_CONSOLE;
}
int
zscngetc(dev_t dev)
{
struct zschan *zs;
zs = zs_get_chan_addr(0, cons_port);
return zs_getc(zs);
}
void
zscnputc(dev_t dev, int c)
{
struct zschan *zs;
zs = zs_get_chan_addr(0, cons_port);
zs_putc(zs, c);
}
void
zscnpollc(dev_t dev, int on)
{
}