2013-04-06 16:48:33 +02:00

175 lines
4.2 KiB
C

/* $NetBSD: zs.c,v 1.3 2008/05/14 13:29:28 tsutsui Exp $ */
/*-
* Copyright (c) 2008 Izumi Tsutsui. 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.
*/
#ifdef CONS_ZS
/*
* optional Z85C30 serial support for Qube 2700
*/
#include <lib/libsa/stand.h>
#include <lib/libkern/libkern.h>
#include <dev/ic/z8530reg.h>
#include <machine/cpu.h>
#include "boot.h"
#include "zs.h"
#define ZSCLOCK 11059200 /* 19200 * 576 */
#define ZS_DELAY() delay(2)
static uint8_t zs_read(void *, uint8_t);
static void zs_write(void *, uint8_t, uint8_t);
static void zs_write_reg(void *, uint8_t, uint8_t);
static void zs_reset(void *);
static uint8_t
zs_read(void *dev, uint8_t reg)
{
volatile uint8_t *zs = dev;
uint8_t val;
val = *(volatile uint8_t *)(zs + reg);
ZS_DELAY();
return val;
}
static void
zs_write(void *dev, uint8_t reg, uint8_t val)
{
volatile uint8_t *zs = dev;
*(volatile uint8_t *)(zs + reg) = val;
ZS_DELAY();
}
static void
zs_write_reg(void *dev, uint8_t reg, uint8_t val)
{
zs_write(dev, ZS_CSR, reg);
zs_write(dev, ZS_CSR, val);
}
static void
zs_reset(void *dev)
{
/* clear errors */
zs_write_reg(dev, 9, 0);
/* hardware reset */
zs_write_reg(dev, 9, ZSWR9_HARD_RESET);
delay(1000);
/* disable all inerttupts */
zs_write_reg(dev, 1, 0);
/* set TX/RX misc parameters and modes */
zs_write_reg(dev, 4, ZSWR4_CLK_X16 | ZSWR4_ONESB | ZSWR4_EVENP);
zs_write_reg(dev, 10, ZSWR10_NRZ);
zs_write_reg(dev, 3, ZSWR3_RX_8);
zs_write_reg(dev, 5, ZSWR5_TX_8 | ZSWR5_DTR | ZSWR5_RTS);
/* sync registers unused */
zs_write_reg(dev, 6, 0);
zs_write_reg(dev, 7, 0);
/* set baud rate generator mode */
zs_write_reg(dev, 14, ZSWR14_BAUD_FROM_PCLK);
/* set clock mode */
zs_write_reg(dev, 11, ZSWR11_RXCLK_BAUD | ZSWR11_TXCLK_BAUD);
/* set baud rate constant */
zs_write_reg(dev, 12, BPS_TO_TCONST(ZSCLOCK / 16, ZSSPEED));
zs_write_reg(dev, 13, 0);
/* enable baud rate generator */
zs_write_reg(dev, 14, ZSWR14_BAUD_FROM_PCLK | ZSWR14_BAUD_ENA);
/* disable all external interrupts */
zs_write_reg(dev, 15, 0);
/* reset external status twice (see src/sys/dev/ic/z8530sc.c) */
zs_write(dev, ZS_CSR, ZSWR0_RESET_STATUS);
zs_write(dev, ZS_CSR, ZSWR0_RESET_STATUS);
/* enable TX and RX */
zs_write_reg(dev, 3, ZSWR3_RX_8 | ZSWR3_RX_ENABLE);
zs_write_reg(dev, 5,
ZSWR5_TX_8 | ZSWR5_DTR | ZSWR5_RTS | ZSWR5_TX_ENABLE);
}
void *
zs_init(int addr, int speed)
{
void *zs;
zs = (void *)MIPS_PHYS_TO_KSEG1(ZS_BASE + addr);
zs_reset(zs);
return zs;
}
void
zs_putc(void *dev, int c)
{
uint8_t csr;
do {
csr = zs_read(dev, ZS_CSR);
} while ((csr & ZSRR0_TX_READY) == 0);
zs_write(dev, ZS_DATA, c);
}
int
zs_getc(void *dev)
{
uint8_t csr, data;
do {
csr = zs_read(dev, ZS_CSR);
} while ((csr & ZSRR0_RX_READY) == 0);
data = zs_read(dev, ZS_DATA);
return data;
}
int
zs_scan(void *dev)
{
uint8_t csr, data;
csr = zs_read(dev, ZS_CSR);
if ((csr & ZSRR0_RX_READY) == 0)
return -1;
data = zs_read(dev, ZS_DATA);
return data;
}
#endif /* CONS_ZS */