1/* $NetBSD: iris_zs.c,v 1.2 2024/05/03 21:38:15 andvar Exp $ */ 2 3/* 4 * Copyright (c) 2018 Naruaki Etomi 5 * All rights reserved. 6 * 7 * Redistribution and use in source and binary forms, with or without 8 * modification, are permitted provided that the following conditions 9 * are met: 10 * 1. Redistributions of source code must retain the above copyright 11 * notice, this list of conditions and the following disclaimer. 12 * 2. Redistributions in binary form must reproduce the above copyright 13 * notice, this list of conditions and the following disclaimer in the 14 * documentation and/or other materials provided with the distribution. 15 * 16 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 17 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 18 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 19 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, 20 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 21 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 22 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 23 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 24 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 25 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 26 */ 27 28/*- 29 * Copyright (c) 1996, 2000 The NetBSD Foundation, Inc. 30 * All rights reserved. 31 * 32 * This code is derived from software contributed to The NetBSD Foundation 33 * by Gordon W. Ross and Wayne Knowles 34 * 35 * Redistribution and use in source and binary forms, with or without 36 * modification, are permitted provided that the following conditions 37 * are met: 38 * 1. Redistributions of source code must retain the above copyright 39 * notice, this list of conditions and the following disclaimer. 40 * 2. Redistributions in binary form must reproduce the above copyright 41 * notice, this list of conditions and the following disclaimer in the 42 * documentation and/or other materials provided with the distribution. 43 * 44 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS 45 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED 46 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 47 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS 48 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 49 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 50 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 51 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 52 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 53 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 54 * POSSIBILITY OF SUCH DAMAGE. 55 */ 56 57/* 58 * Silicon Graphics "IRIS" series MIPS processors machine bootloader. 59 * Zilog Z8530 Dual UART driver. 60 * Most of the following was adapted from /sys/arch/sgimips/dev/zs.c. 61 * NetBSD: zs.c,v 1.39 2015/02/18 16:47:58 macallan Exp 62 */ 63 64#include <lib/libsa/stand.h> 65#include <lib/libkern/libkern.h> 66 67#include <dev/ic/z8530reg.h> 68 69#include <mips/cpuregs.h> 70#include <machine/cpu.h> 71 72#include "iris_machdep.h" 73#include "iris_zs.h" 74 75#define ZSCLOCK 3672000 /* PCLK pin input clock rate */ 76#define ZS_DELAY() DELAY(3) 77#define ZS_DEFSPEED 9600 78 79static void zs_write(void *, uint8_t); 80static void zs_write_reg(void *, uint8_t, uint8_t); 81static void zs_reset(void *); 82static struct zschan *zs_get_chan_addr(int zs_unit, int channel); 83int zs_getc(void *); 84void zs_putc(void *, int); 85int zs_scan(void *); 86 87static int cons_port; 88 89static void 90zs_write(void *dev, uint8_t val) 91{ 92 struct zschan *zc = dev; 93 94 zc->zc_csr = val; 95 ZS_DELAY(); 96} 97 98static void 99zs_write_reg(void *dev, uint8_t reg, uint8_t val) 100{ 101 102 zs_write(dev, reg); 103 zs_write(dev, val); 104} 105 106static void 107zs_reset(void *dev) 108{ 109 110 /* clear errors */ 111 zs_write_reg(dev, 9, 0); 112 /* hardware reset */ 113 zs_write_reg(dev, 9, ZSWR9_HARD_RESET); 114 DELAY(1000); 115 116 /* disable all interrupts */ 117 zs_write_reg(dev, 1, 0); 118 119 /* set TX/RX misc parameters and modes */ 120 zs_write_reg(dev, 4, ZSWR4_CLK_X16 | ZSWR4_ONESB | ZSWR4_EVENP); 121 zs_write_reg(dev, 10, ZSWR10_NRZ); 122 zs_write_reg(dev, 3, ZSWR3_RX_8); 123 zs_write_reg(dev, 5, ZSWR5_TX_8 | ZSWR5_DTR | ZSWR5_RTS); 124 125 /* sync registers unused */ 126 zs_write_reg(dev, 6, 0); 127 zs_write_reg(dev, 7, 0); 128 129 /* set clock mode */ 130 zs_write_reg(dev, 11, 131 ZSWR11_RXCLK_BAUD | ZSWR11_TXCLK_BAUD | ZSWR11_TRXC_OUT_ENA); 132 133 /* set baud rate constant */ 134 zs_write_reg(dev, 12, BPS_TO_TCONST(ZSCLOCK / 16, ZS_DEFSPEED)); 135 zs_write_reg(dev, 13, 0); 136 137 /* enable baud rate generator */ 138 zs_write_reg(dev, 14, ZSWR14_BAUD_ENA); 139 140 /* disable all external interrupts */ 141 zs_write_reg(dev, 15, 0); 142 143 /* reset external status twice (see src/sys/dev/ic/z8530sc.c) */ 144 zs_write(dev, ZSWR0_RESET_STATUS); 145 zs_write(dev, ZSWR0_RESET_STATUS); 146 147 /* enable TX and RX */ 148 zs_write_reg(dev, 3, ZSWR3_RX_8 | ZSWR3_RX_ENABLE); 149 zs_write_reg(dev, 5, 150 ZSWR5_TX_8 | ZSWR5_DTR | ZSWR5_RTS | ZSWR5_TX_ENABLE); 151} 152 153static struct zschan * 154zs_get_chan_addr(int zs_unit, int channel) 155{ 156 struct zsdevice *addr; 157 struct zschan *zc; 158 159 addr = (struct zsdevice *)MIPS_PHYS_TO_KSEG1(ZS_ADDR); 160 161 zc = &addr->zs_chan_b; 162 163 return zc; 164} 165 166void * 167zs_init(int addr, int speed) 168{ 169 struct zschan *zs; 170 cons_port = 0; 171 172 zs = zs_get_chan_addr(1, cons_port); 173 174 zs_reset(zs); 175 176 return zs; 177} 178 179void 180zscnputc(void *dev, int c) 181{ 182 struct zschan *zs; 183 184 zs = zs_get_chan_addr(1, cons_port); 185 186 zs_putc(zs, c); 187} 188 189void 190zs_putc(void *arg, int c) 191{ 192 register volatile struct zschan *zc = arg; 193 register int rr0; 194 195 /* Wait for transmitter to become ready. */ 196 do { 197 rr0 = zc->zc_csr; 198 ZS_DELAY(); 199 } while ((rr0 & ZSRR0_TX_READY) == 0); 200 201 zc->zc_data = c; 202 ZS_DELAY(); 203} 204 205int 206zscngetc(void *dev) 207{ 208 struct zschan *zs; 209 210 zs = zs_get_chan_addr(1, cons_port); 211 212 return zs_getc(zs); 213} 214 215int 216zs_getc(void *arg) 217{ 218 struct zschan *zc = arg; 219 int c, rr0; 220 221 /* Wait for a character to arrive. */ 222 do { 223 rr0 = zc->zc_csr; 224 ZS_DELAY(); 225 } while ((rr0 & ZSRR0_RX_READY) == 0); 226 227 c = zc->zc_data; 228 ZS_DELAY(); 229 230 return c; 231} 232 233int 234zscnscanc(void *dev) 235{ 236 struct zschan *zs; 237 238 zs = zs_get_chan_addr(1, cons_port); 239 240 return zs_scan(zs); 241} 242 243int 244zs_scan(void *arg) 245{ 246 struct zschan *zc = arg; 247 int c, rr0; 248 249 /* Wait for a character to arrive. */ 250 rr0 = zc->zc_csr; 251 ZS_DELAY(); 252 253 if ((rr0 & ZSRR0_RX_READY) == 0) { 254 return -1; 255 } 256 257 c = zc->zc_data; 258 ZS_DELAY(); 259 260 return c; 261} 262