1 /*- 2 * SPDX-License-Identifier: BSD-2-Clause 3 * 4 * Copyright (c) 2004 Marcel Moolenaar 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 * 11 * 1. Redistributions of source code must retain the above copyright 12 * notice, this list of conditions and the following disclaimer. 13 * 2. Redistributions in binary form must reproduce the above copyright 14 * notice, this list of conditions and the following disclaimer in the 15 * documentation and/or other materials provided with the distribution. 16 * 17 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 18 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 19 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 20 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, 21 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 22 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 23 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 24 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 25 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 26 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 27 */ 28 29 #include <sys/cdefs.h> 30 #include <sys/param.h> 31 #include <sys/systm.h> 32 #include <sys/bus.h> 33 34 #include <machine/bus.h> 35 #include <machine/vmparam.h> 36 37 #include <dev/uart/uart.h> 38 #include <dev/uart/uart_cpu.h> 39 40 #define UART_TAG_BR 0 41 #define UART_TAG_CH 1 42 #define UART_TAG_DB 2 43 #define UART_TAG_DT 3 44 #define UART_TAG_IO 4 45 #define UART_TAG_MM 5 46 #define UART_TAG_PA 6 47 #define UART_TAG_RS 7 48 #define UART_TAG_SB 8 49 #define UART_TAG_XO 9 50 #define UART_TAG_BD 10 51 52 static struct uart_class *uart_classes[] = { 53 &uart_ns8250_class, 54 &uart_z8530_class, 55 }; 56 57 static bus_addr_t 58 uart_parse_addr(const char **p) 59 { 60 return (strtoul(*p, (char**)(uintptr_t)p, 0)); 61 } 62 63 static struct uart_class * 64 uart_parse_class(struct uart_class *class, const char **p) 65 { 66 struct uart_class *uc; 67 const char *nm; 68 size_t len; 69 u_int i; 70 71 for (i = 0; i < nitems(uart_classes); i++) { 72 uc = uart_classes[i]; 73 nm = uart_getname(uc); 74 if (nm == NULL || *nm == '\0') 75 continue; 76 len = strlen(nm); 77 if (strncmp(nm, *p, len) == 0) { 78 *p += len; 79 return (uc); 80 } 81 } 82 return (class); 83 } 84 85 static long 86 uart_parse_long(const char **p) 87 { 88 return (strtol(*p, (char**)(uintptr_t)p, 0)); 89 } 90 91 static int 92 uart_parse_parity(const char **p) 93 { 94 if (!strncmp(*p, "even", 4)) { 95 *p += 4; 96 return UART_PARITY_EVEN; 97 } 98 if (!strncmp(*p, "mark", 4)) { 99 *p += 4; 100 return UART_PARITY_MARK; 101 } 102 if (!strncmp(*p, "none", 4)) { 103 *p += 4; 104 return UART_PARITY_NONE; 105 } 106 if (!strncmp(*p, "odd", 3)) { 107 *p += 3; 108 return UART_PARITY_ODD; 109 } 110 if (!strncmp(*p, "space", 5)) { 111 *p += 5; 112 return UART_PARITY_SPACE; 113 } 114 return (-1); 115 } 116 117 static int 118 uart_parse_tag(const char **p) 119 { 120 int tag; 121 122 if ((*p)[0] == 'b' && (*p)[1] == 'd') { 123 tag = UART_TAG_BD; 124 goto out; 125 } 126 if ((*p)[0] == 'b' && (*p)[1] == 'r') { 127 tag = UART_TAG_BR; 128 goto out; 129 } 130 if ((*p)[0] == 'c' && (*p)[1] == 'h') { 131 tag = UART_TAG_CH; 132 goto out; 133 } 134 if ((*p)[0] == 'd' && (*p)[1] == 'b') { 135 tag = UART_TAG_DB; 136 goto out; 137 } 138 if ((*p)[0] == 'd' && (*p)[1] == 't') { 139 tag = UART_TAG_DT; 140 goto out; 141 } 142 if ((*p)[0] == 'i' && (*p)[1] == 'o') { 143 tag = UART_TAG_IO; 144 goto out; 145 } 146 if ((*p)[0] == 'm' && (*p)[1] == 'm') { 147 tag = UART_TAG_MM; 148 goto out; 149 } 150 if ((*p)[0] == 'p' && (*p)[1] == 'a') { 151 tag = UART_TAG_PA; 152 goto out; 153 } 154 if ((*p)[0] == 'r' && (*p)[1] == 's') { 155 tag = UART_TAG_RS; 156 goto out; 157 } 158 if ((*p)[0] == 's' && (*p)[1] == 'b') { 159 tag = UART_TAG_SB; 160 goto out; 161 } 162 if ((*p)[0] == 'x' && (*p)[1] == 'o') { 163 tag = UART_TAG_XO; 164 goto out; 165 } 166 return (-1); 167 168 out: 169 *p += 2; 170 if ((*p)[0] != ':' && (*p)[0] != '=') 171 return (-1); 172 (*p)++; 173 return (tag); 174 } 175 176 /* 177 * Parse a device specification. The specification is a list of attributes 178 * separated by commas. Each attribute is a tag-value pair with the tag and 179 * value separated by a colon. Supported tags are: 180 * 181 * bd = Busy Detect 182 * br = Baudrate 183 * ch = Channel 184 * db = Data bits 185 * dt = Device type 186 * io = I/O port address 187 * mm = Memory mapped I/O address 188 * pa = Parity 189 * rs = Register shift 190 * sb = Stopbits 191 * xo = Device clock (xtal oscillator) 192 * 193 * The io and mm tags are mutually exclusive. 194 */ 195 196 int 197 uart_getenv(int devtype, struct uart_devinfo *di, struct uart_class *class) 198 { 199 const char *spec; 200 char *cp; 201 bus_addr_t addr = ~0U; 202 int error; 203 204 /* 205 * All uart_class references are weak. Make sure the default 206 * device class has been compiled-in. 207 */ 208 if (class == NULL) 209 return (ENXIO); 210 211 /* 212 * Check the environment variables "hw.uart.console" and 213 * "hw.uart.dbgport". These variables, when present, specify 214 * which UART port is to be used as serial console or debug 215 * port (resp). 216 */ 217 switch (devtype) { 218 case UART_DEV_CONSOLE: 219 cp = kern_getenv("hw.uart.console"); 220 break; 221 case UART_DEV_DBGPORT: 222 cp = kern_getenv("hw.uart.dbgport"); 223 break; 224 default: 225 cp = NULL; 226 break; 227 } 228 229 if (cp == NULL) 230 return (ENXIO); 231 232 /* Set defaults. */ 233 di->bas.chan = 0; 234 di->bas.regshft = 0; 235 di->bas.rclk = 0; 236 di->baudrate = 0; 237 di->databits = 8; 238 di->stopbits = 1; 239 di->parity = UART_PARITY_NONE; 240 241 /* Parse the attributes. */ 242 spec = cp; 243 for (;;) { 244 switch (uart_parse_tag(&spec)) { 245 case UART_TAG_BD: 246 di->bas.busy_detect = uart_parse_long(&spec); 247 break; 248 case UART_TAG_BR: 249 di->baudrate = uart_parse_long(&spec); 250 break; 251 case UART_TAG_CH: 252 di->bas.chan = uart_parse_long(&spec); 253 break; 254 case UART_TAG_DB: 255 di->databits = uart_parse_long(&spec); 256 break; 257 case UART_TAG_DT: 258 class = uart_parse_class(class, &spec); 259 break; 260 case UART_TAG_IO: 261 di->bas.bst = uart_bus_space_io; 262 addr = uart_parse_addr(&spec); 263 break; 264 case UART_TAG_MM: 265 di->bas.bst = uart_bus_space_mem; 266 addr = uart_parse_addr(&spec); 267 break; 268 case UART_TAG_PA: 269 di->parity = uart_parse_parity(&spec); 270 break; 271 case UART_TAG_RS: 272 di->bas.regshft = uart_parse_long(&spec); 273 break; 274 case UART_TAG_SB: 275 di->stopbits = uart_parse_long(&spec); 276 break; 277 case UART_TAG_XO: 278 di->bas.rclk = uart_parse_long(&spec); 279 break; 280 default: 281 goto inval; 282 } 283 if (*spec == '\0') 284 break; 285 if (*spec != ',') 286 goto inval; 287 spec++; 288 } 289 290 /* 291 * If we still have an invalid address, the specification must be 292 * missing an I/O port or memory address. We don't like that. 293 */ 294 if (addr == ~0U) 295 goto inval; 296 freeenv(cp); 297 298 /* 299 * Accept only the well-known baudrates. Any invalid baudrate 300 * is silently replaced with a 0-valued baudrate. The 0 baudrate 301 * has special meaning. It means that we're not supposed to 302 * program the baudrate and simply communicate with whatever 303 * speed the hardware is currently programmed for. 304 */ 305 if (di->baudrate >= 19200) { 306 if (di->baudrate % 19200) 307 di->baudrate = 0; 308 } else if (di->baudrate >= 1200) { 309 if (di->baudrate % 1200) 310 di->baudrate = 0; 311 } else if (di->baudrate > 0) { 312 if (di->baudrate % 75) 313 di->baudrate = 0; 314 } else 315 di->baudrate = 0; 316 317 /* Set the ops and create a bus space handle. */ 318 di->ops = uart_getops(class); 319 error = bus_space_map(di->bas.bst, addr, uart_getrange(class), 0, 320 &di->bas.bsh); 321 return (error); 322 inval: 323 printf("warning: bad uart specification: %s\n", cp); 324 freeenv(cp); 325 return (EINVAL); 326 } 327