comio_direct.c revision 1.1.2.3
1 1.1.2.2 thorpej /*- 2 1.1.2.2 thorpej * Copyright (c) 1993, 1994, 1995, 1996, 1997 3 1.1.2.2 thorpej * Charles M. Hannum. All rights reserved. 4 1.1.2.2 thorpej * 5 1.1.2.2 thorpej * Taken from sys/dev/isa/com.c and integrated into standalone boot 6 1.1.2.2 thorpej * programs by Martin Husemann. 7 1.1.2.2 thorpej * 8 1.1.2.2 thorpej * Redistribution and use in source and binary forms, with or without 9 1.1.2.2 thorpej * modification, are permitted provided that the following conditions 10 1.1.2.2 thorpej * are met: 11 1.1.2.2 thorpej * 1. Redistributions of source code must retain the above copyright 12 1.1.2.2 thorpej * notice, this list of conditions and the following disclaimer. 13 1.1.2.2 thorpej * 2. Redistributions in binary form must reproduce the above copyright 14 1.1.2.2 thorpej * notice, this list of conditions and the following disclaimer in the 15 1.1.2.2 thorpej * documentation and/or other materials provided with the distribution. 16 1.1.2.2 thorpej * 3. All advertising materials mentioning features or use of this software 17 1.1.2.2 thorpej * must display the following acknowledgement: 18 1.1.2.2 thorpej * This product includes software developed by Charles M. Hannum. 19 1.1.2.2 thorpej * 4. The name of the author may not be used to endorse or promote products 20 1.1.2.2 thorpej * derived from this software without specific prior written permission. 21 1.1.2.2 thorpej * 22 1.1.2.2 thorpej * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 23 1.1.2.2 thorpej * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 24 1.1.2.2 thorpej * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 25 1.1.2.2 thorpej * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, 26 1.1.2.2 thorpej * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 27 1.1.2.2 thorpej * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 28 1.1.2.2 thorpej * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 29 1.1.2.2 thorpej * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 30 1.1.2.2 thorpej * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 31 1.1.2.2 thorpej * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 32 1.1.2.2 thorpej */ 33 1.1.2.2 thorpej 34 1.1.2.2 thorpej /* 35 1.1.2.2 thorpej * Copyright (c) 1991 The Regents of the University of California. 36 1.1.2.2 thorpej * All rights reserved. 37 1.1.2.2 thorpej * 38 1.1.2.2 thorpej * Redistribution and use in source and binary forms, with or without 39 1.1.2.2 thorpej * modification, are permitted provided that the following conditions 40 1.1.2.2 thorpej * are met: 41 1.1.2.2 thorpej * 1. Redistributions of source code must retain the above copyright 42 1.1.2.2 thorpej * notice, this list of conditions and the following disclaimer. 43 1.1.2.2 thorpej * 2. Redistributions in binary form must reproduce the above copyright 44 1.1.2.2 thorpej * notice, this list of conditions and the following disclaimer in the 45 1.1.2.2 thorpej * documentation and/or other materials provided with the distribution. 46 1.1.2.2 thorpej * 3. All advertising materials mentioning features or use of this software 47 1.1.2.2 thorpej * must display the following acknowledgement: 48 1.1.2.2 thorpej * This product includes software developed by the University of 49 1.1.2.2 thorpej * California, Berkeley and its contributors. 50 1.1.2.2 thorpej * 4. Neither the name of the University nor the names of its contributors 51 1.1.2.2 thorpej * may be used to endorse or promote products derived from this software 52 1.1.2.2 thorpej * without specific prior written permission. 53 1.1.2.2 thorpej * 54 1.1.2.2 thorpej * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 55 1.1.2.2 thorpej * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 56 1.1.2.2 thorpej * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 57 1.1.2.2 thorpej * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 58 1.1.2.2 thorpej * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 59 1.1.2.2 thorpej * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 60 1.1.2.2 thorpej * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 61 1.1.2.2 thorpej * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 62 1.1.2.2 thorpej * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 63 1.1.2.2 thorpej * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 64 1.1.2.2 thorpej * SUCH DAMAGE. 65 1.1.2.2 thorpej * 66 1.1.2.2 thorpej * @(#)com.c 7.5 (Berkeley) 5/16/91 67 1.1.2.2 thorpej */ 68 1.1.2.2 thorpej 69 1.1.2.2 thorpej #include <sys/types.h> 70 1.1.2.2 thorpej #include <lib/libsa/stand.h> 71 1.1.2.2 thorpej #include <machine/pio.h> 72 1.1.2.3 thorpej #include <dev/ic/comreg.h> 73 1.1.2.2 thorpej #include "comio_direct.h" 74 1.1.2.2 thorpej 75 1.1.2.2 thorpej static int comspeed __P((long speed)); 76 1.1.2.2 thorpej 77 1.1.2.2 thorpej /* preread buffer for xon/xoff handling */ 78 1.1.2.2 thorpej #define XON 0x11 79 1.1.2.2 thorpej #define XOFF 0x13 80 1.1.2.2 thorpej #define SERBUFSIZE 16 81 1.1.2.2 thorpej static u_char serbuf[SERBUFSIZE]; 82 1.1.2.2 thorpej static int serbuf_read = 0; 83 1.1.2.2 thorpej static int serbuf_write = 0; 84 1.1.2.2 thorpej static int stopped = 0; 85 1.1.2.2 thorpej 86 1.1.2.2 thorpej #define ISSET(t,f) ((t) & (f)) 87 1.1.2.2 thorpej 88 1.1.2.2 thorpej /* 89 1.1.2.2 thorpej * calculate divisor for a given speed 90 1.1.2.2 thorpej */ 91 1.1.2.2 thorpej static int 92 1.1.2.2 thorpej comspeed(speed) 93 1.1.2.2 thorpej long speed; 94 1.1.2.2 thorpej { 95 1.1.2.2 thorpej #define divrnd(n, q) (((n)*2/(q)+1)/2) /* divide and round off */ 96 1.1.2.2 thorpej 97 1.1.2.2 thorpej int x, err; 98 1.1.2.2 thorpej 99 1.1.2.2 thorpej #if 0 100 1.1.2.2 thorpej if (speed == 0) 101 1.1.2.2 thorpej return (0); 102 1.1.2.2 thorpej #endif 103 1.1.2.2 thorpej if (speed <= 0) 104 1.1.2.2 thorpej return (-1); 105 1.1.2.2 thorpej x = divrnd((COM_FREQ / 16), speed); 106 1.1.2.2 thorpej if (x <= 0) 107 1.1.2.2 thorpej return (-1); 108 1.1.2.2 thorpej err = divrnd((COM_FREQ / 16) * 1000, speed * x) - 1000; 109 1.1.2.2 thorpej if (err < 0) 110 1.1.2.2 thorpej err = -err; 111 1.1.2.2 thorpej if (err > COM_TOLERANCE) 112 1.1.2.2 thorpej return (-1); 113 1.1.2.2 thorpej return (x); 114 1.1.2.2 thorpej 115 1.1.2.2 thorpej #undef divrnd(n, q) 116 1.1.2.2 thorpej } 117 1.1.2.2 thorpej 118 1.1.2.2 thorpej /* 119 1.1.2.2 thorpej * get a character 120 1.1.2.2 thorpej */ 121 1.1.2.2 thorpej int 122 1.1.2.2 thorpej comgetc_d(combase) 123 1.1.2.2 thorpej int combase; 124 1.1.2.2 thorpej { 125 1.1.2.2 thorpej u_char stat, c; 126 1.1.2.2 thorpej 127 1.1.2.2 thorpej if (serbuf_read != serbuf_write) { 128 1.1.2.2 thorpej c = serbuf[serbuf_read++]; 129 1.1.2.2 thorpej if (serbuf_read >= SERBUFSIZE) 130 1.1.2.2 thorpej serbuf_read = 0; 131 1.1.2.2 thorpej return c; 132 1.1.2.2 thorpej } 133 1.1.2.2 thorpej 134 1.1.2.2 thorpej for (;;) { 135 1.1.2.2 thorpej while (!ISSET(stat = inb(combase + com_lsr), LSR_RXRDY)) 136 1.1.2.2 thorpej ; 137 1.1.2.2 thorpej c = inb(combase + com_data); 138 1.1.2.2 thorpej inb(combase + com_iir); 139 1.1.2.2 thorpej if (c != XOFF) { 140 1.1.2.2 thorpej stopped = 0; 141 1.1.2.2 thorpej break; /* got a real char, deliver it... */ 142 1.1.2.2 thorpej } 143 1.1.2.2 thorpej stopped = 1; 144 1.1.2.2 thorpej } 145 1.1.2.2 thorpej return (c); 146 1.1.2.2 thorpej } 147 1.1.2.2 thorpej 148 1.1.2.2 thorpej /* 149 1.1.2.2 thorpej * output a character, return nonzero on success 150 1.1.2.2 thorpej */ 151 1.1.2.2 thorpej int 152 1.1.2.2 thorpej computc_d(c, combase) 153 1.1.2.2 thorpej int c; 154 1.1.2.2 thorpej int combase; 155 1.1.2.2 thorpej { 156 1.1.2.2 thorpej u_char stat; 157 1.1.2.2 thorpej register int timo; 158 1.1.2.2 thorpej 159 1.1.2.2 thorpej /* check for old XOFF */ 160 1.1.2.2 thorpej while (stopped) 161 1.1.2.2 thorpej comgetc_d(combase); /* wait for XON */ 162 1.1.2.2 thorpej 163 1.1.2.2 thorpej /* check for new XOFF */ 164 1.1.2.2 thorpej if (comstatus_d(combase)) { 165 1.1.2.2 thorpej int c = comgetc_d(combase); /* XOFF handled in comgetc_d */ 166 1.1.2.2 thorpej /* stuff char into preread buffer */ 167 1.1.2.2 thorpej serbuf[serbuf_write++] = c; 168 1.1.2.2 thorpej if (serbuf_write >= SERBUFSIZE) 169 1.1.2.2 thorpej serbuf_write = 0; 170 1.1.2.2 thorpej } 171 1.1.2.2 thorpej 172 1.1.2.2 thorpej /* wait for any pending transmission to finish */ 173 1.1.2.2 thorpej timo = 50000; 174 1.1.2.2 thorpej while (!ISSET(stat = inb(combase + com_lsr), LSR_TXRDY) 175 1.1.2.2 thorpej && --timo) 176 1.1.2.2 thorpej ; 177 1.1.2.2 thorpej if (timo == 0) return 0; 178 1.1.2.2 thorpej outb(combase + com_data, c); 179 1.1.2.2 thorpej /* wait for this transmission to complete */ 180 1.1.2.2 thorpej timo = 1500000; 181 1.1.2.2 thorpej while (!ISSET(stat = inb(combase + com_lsr), LSR_TXRDY) 182 1.1.2.2 thorpej && --timo) 183 1.1.2.2 thorpej ; 184 1.1.2.2 thorpej if (timo == 0) return 0; 185 1.1.2.2 thorpej /* clear any interrupts generated by this transmission */ 186 1.1.2.2 thorpej inb(combase + com_iir); 187 1.1.2.2 thorpej 188 1.1.2.2 thorpej return 1; 189 1.1.2.2 thorpej } 190 1.1.2.2 thorpej 191 1.1.2.2 thorpej /* 192 1.1.2.2 thorpej * Initialize UART to known state. 193 1.1.2.2 thorpej */ 194 1.1.2.2 thorpej void 195 1.1.2.2 thorpej cominit_d(combase) 196 1.1.2.2 thorpej int combase; 197 1.1.2.2 thorpej { 198 1.1.2.2 thorpej int rate; 199 1.1.2.2 thorpej 200 1.1.2.2 thorpej serbuf_read = 0; 201 1.1.2.2 thorpej serbuf_write = 0; 202 1.1.2.2 thorpej 203 1.1.2.2 thorpej outb(combase + com_cfcr, LCR_DLAB); 204 1.1.2.2 thorpej #ifdef CONSPEED 205 1.1.2.2 thorpej rate = comspeed(CONSPEED); 206 1.1.2.2 thorpej #else 207 1.1.2.2 thorpej rate = comspeed(9600); 208 1.1.2.2 thorpej #endif 209 1.1.2.2 thorpej outb(combase + com_dlbl, rate); 210 1.1.2.2 thorpej outb(combase + com_dlbh, rate >> 8); 211 1.1.2.2 thorpej outb(combase + com_cfcr, LCR_8BITS); 212 1.1.2.2 thorpej outb(combase + com_mcr, 0); 213 1.1.2.2 thorpej outb(combase + com_fifo, 214 1.1.2.2 thorpej FIFO_ENABLE | FIFO_RCV_RST | FIFO_XMT_RST | FIFO_TRIGGER_1); 215 1.1.2.2 thorpej outb(combase + com_ier, 0); 216 1.1.2.2 thorpej } 217 1.1.2.2 thorpej 218 1.1.2.2 thorpej /* 219 1.1.2.2 thorpej * return nonzero if input char available, do XON/XOFF handling 220 1.1.2.2 thorpej */ 221 1.1.2.2 thorpej int 222 1.1.2.2 thorpej comstatus_d(combase) 223 1.1.2.2 thorpej int combase; 224 1.1.2.2 thorpej { 225 1.1.2.2 thorpej /* check if any preread input is already there */ 226 1.1.2.2 thorpej if (serbuf_read != serbuf_write) return 1; 227 1.1.2.2 thorpej 228 1.1.2.2 thorpej /* check for new stuff on the port */ 229 1.1.2.2 thorpej if (ISSET(inb(combase + com_lsr), LSR_RXRDY)) { 230 1.1.2.2 thorpej /* this could be XOFF, which we would swallow, so we can't 231 1.1.2.2 thorpej claim there is input available... */ 232 1.1.2.2 thorpej int c = inb(combase + com_data); 233 1.1.2.2 thorpej inb(combase + com_iir); 234 1.1.2.2 thorpej if (c == XOFF) { 235 1.1.2.2 thorpej stopped = 1; 236 1.1.2.2 thorpej } else { 237 1.1.2.2 thorpej /* stuff char into preread buffer */ 238 1.1.2.2 thorpej serbuf[serbuf_write++] = c; 239 1.1.2.2 thorpej if (serbuf_write >= SERBUFSIZE) 240 1.1.2.2 thorpej serbuf_write = 0; 241 1.1.2.2 thorpej return 1; 242 1.1.2.2 thorpej } 243 1.1.2.2 thorpej } 244 1.1.2.2 thorpej 245 1.1.2.2 thorpej return 0; /* nothing out there... */ 246 1.1.2.2 thorpej } 247
Indexes created Fri Oct 03 02:09:57 GMT 2025