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 __FBSDID("$FreeBSD$"); 31 32 #include <sys/param.h> 33 #include <sys/systm.h> 34 #include <sys/bus.h> 35 36 #include <machine/bus.h> 37 #include <machine/vmparam.h> 38 39 #include <dev/uart/uart.h> 40 #include <dev/uart/uart_cpu.h> 41 42 #define UART_TAG_BR 0 43 #define UART_TAG_CH 1 44 #define UART_TAG_DB 2 45 #define UART_TAG_DT 3 46 #define UART_TAG_IO 4 47 #define UART_TAG_MM 5 48 #define UART_TAG_PA 6 49 #define UART_TAG_RS 7 50 #define UART_TAG_SB 8 51 #define UART_TAG_XO 9 52 #define UART_TAG_BD 10 53 54 static struct uart_class *uart_classes[] = { 55 &uart_ns8250_class, 56 &uart_z8530_class, 57 }; 58 59 static bus_addr_t 60 uart_parse_addr(const char **p) 61 { 62 return (strtoul(*p, (char**)(uintptr_t)p, 0)); 63 } 64 65 static struct uart_class * 66 uart_parse_class(struct uart_class *class, const char **p) 67 { 68 struct uart_class *uc; 69 const char *nm; 70 size_t len; 71 u_int i; 72 73 for (i = 0; i < nitems(uart_classes); i++) { 74 uc = uart_classes[i]; 75 nm = uart_getname(uc); 76 if (nm == NULL || *nm == '\0') 77 continue; 78 len = strlen(nm); 79 if (strncmp(nm, *p, len) == 0) { 80 *p += len; 81 return (uc); 82 } 83 } 84 return (class); 85 } 86 87 static long 88 uart_parse_long(const char **p) 89 { 90 return (strtol(*p, (char**)(uintptr_t)p, 0)); 91 } 92 93 static int 94 uart_parse_parity(const char **p) 95 { 96 if (!strncmp(*p, "even", 4)) { 97 *p += 4; 98 return UART_PARITY_EVEN; 99 } 100 if (!strncmp(*p, "mark", 4)) { 101 *p += 4; 102 return UART_PARITY_MARK; 103 } 104 if (!strncmp(*p, "none", 4)) { 105 *p += 4; 106 return UART_PARITY_NONE; 107 } 108 if (!strncmp(*p, "odd", 3)) { 109 *p += 3; 110 return UART_PARITY_ODD; 111 } 112 if (!strncmp(*p, "space", 5)) { 113 *p += 5; 114 return UART_PARITY_SPACE; 115 } 116 return (-1); 117 } 118 119 static int 120 uart_parse_tag(const char **p) 121 { 122 int tag; 123 124 if ((*p)[0] == 'b' && (*p)[1] == 'd') { 125 tag = UART_TAG_BD; 126 goto out; 127 } 128 if ((*p)[0] == 'b' && (*p)[1] == 'r') { 129 tag = UART_TAG_BR; 130 goto out; 131 } 132 if ((*p)[0] == 'c' && (*p)[1] == 'h') { 133 tag = UART_TAG_CH; 134 goto out; 135 } 136 if ((*p)[0] == 'd' && (*p)[1] == 'b') { 137 tag = UART_TAG_DB; 138 goto out; 139 } 140 if ((*p)[0] == 'd' && (*p)[1] == 't') { 141 tag = UART_TAG_DT; 142 goto out; 143 } 144 if ((*p)[0] == 'i' && (*p)[1] == 'o') { 145 tag = UART_TAG_IO; 146 goto out; 147 } 148 if ((*p)[0] == 'm' && (*p)[1] == 'm') { 149 tag = UART_TAG_MM; 150 goto out; 151 } 152 if ((*p)[0] == 'p' && (*p)[1] == 'a') { 153 tag = UART_TAG_PA; 154 goto out; 155 } 156 if ((*p)[0] == 'r' && (*p)[1] == 's') { 157 tag = UART_TAG_RS; 158 goto out; 159 } 160 if ((*p)[0] == 's' && (*p)[1] == 'b') { 161 tag = UART_TAG_SB; 162 goto out; 163 } 164 if ((*p)[0] == 'x' && (*p)[1] == 'o') { 165 tag = UART_TAG_XO; 166 goto out; 167 } 168 return (-1); 169 170 out: 171 *p += 2; 172 if ((*p)[0] != ':' && (*p)[0] != '=') 173 return (-1); 174 (*p)++; 175 return (tag); 176 } 177 178 /* 179 * Parse a device specification. The specification is a list of attributes 180 * separated by commas. Each attribute is a tag-value pair with the tag and 181 * value separated by a colon. Supported tags are: 182 * 183 * bd = Busy Detect 184 * br = Baudrate 185 * ch = Channel 186 * db = Data bits 187 * dt = Device type 188 * io = I/O port address 189 * mm = Memory mapped I/O address 190 * pa = Parity 191 * rs = Register shift 192 * sb = Stopbits 193 * xo = Device clock (xtal oscillator) 194 * 195 * The io and mm tags are mutually exclusive. 196 */ 197 198 int 199 uart_getenv(int devtype, struct uart_devinfo *di, struct uart_class *class) 200 { 201 const char *spec; 202 char *cp; 203 bus_addr_t addr = ~0U; 204 int error; 205 206 /* 207 * All uart_class references are weak. Make sure the default 208 * device class has been compiled-in. 209 */ 210 if (class == NULL) 211 return (ENXIO); 212 213 /* 214 * Check the environment variables "hw.uart.console" and 215 * "hw.uart.dbgport". These variables, when present, specify 216 * which UART port is to be used as serial console or debug 217 * port (resp). 218 */ 219 switch (devtype) { 220 case UART_DEV_CONSOLE: 221 cp = kern_getenv("hw.uart.console"); 222 break; 223 case UART_DEV_DBGPORT: 224 cp = kern_getenv("hw.uart.dbgport"); 225 break; 226 default: 227 cp = NULL; 228 break; 229 } 230 231 if (cp == NULL) 232 return (ENXIO); 233 234 /* Set defaults. */ 235 di->bas.chan = 0; 236 di->bas.regshft = 0; 237 di->bas.rclk = 0; 238 di->baudrate = 0; 239 di->databits = 8; 240 di->stopbits = 1; 241 di->parity = UART_PARITY_NONE; 242 243 /* Parse the attributes. */ 244 spec = cp; 245 for (;;) { 246 switch (uart_parse_tag(&spec)) { 247 case UART_TAG_BD: 248 di->bas.busy_detect = uart_parse_long(&spec); 249 break; 250 case UART_TAG_BR: 251 di->baudrate = uart_parse_long(&spec); 252 break; 253 case UART_TAG_CH: 254 di->bas.chan = uart_parse_long(&spec); 255 break; 256 case UART_TAG_DB: 257 di->databits = uart_parse_long(&spec); 258 break; 259 case UART_TAG_DT: 260 class = uart_parse_class(class, &spec); 261 break; 262 case UART_TAG_IO: 263 di->bas.bst = uart_bus_space_io; 264 addr = uart_parse_addr(&spec); 265 break; 266 case UART_TAG_MM: 267 di->bas.bst = uart_bus_space_mem; 268 addr = uart_parse_addr(&spec); 269 break; 270 case UART_TAG_PA: 271 di->parity = uart_parse_parity(&spec); 272 break; 273 case UART_TAG_RS: 274 di->bas.regshft = uart_parse_long(&spec); 275 break; 276 case UART_TAG_SB: 277 di->stopbits = uart_parse_long(&spec); 278 break; 279 case UART_TAG_XO: 280 di->bas.rclk = uart_parse_long(&spec); 281 break; 282 default: 283 goto inval; 284 } 285 if (*spec == '\0') 286 break; 287 if (*spec != ',') 288 goto inval; 289 spec++; 290 } 291 292 /* 293 * If we still have an invalid address, the specification must be 294 * missing an I/O port or memory address. We don't like that. 295 */ 296 if (addr == ~0U) 297 goto inval; 298 freeenv(cp); 299 300 /* 301 * Accept only the well-known baudrates. Any invalid baudrate 302 * is silently replaced with a 0-valued baudrate. The 0 baudrate 303 * has special meaning. It means that we're not supposed to 304 * program the baudrate and simply communicate with whatever 305 * speed the hardware is currently programmed for. 306 */ 307 if (di->baudrate >= 19200) { 308 if (di->baudrate % 19200) 309 di->baudrate = 0; 310 } else if (di->baudrate >= 1200) { 311 if (di->baudrate % 1200) 312 di->baudrate = 0; 313 } else if (di->baudrate > 0) { 314 if (di->baudrate % 75) 315 di->baudrate = 0; 316 } else 317 di->baudrate = 0; 318 319 /* Set the ops and create a bus space handle. */ 320 di->ops = uart_getops(class); 321 error = bus_space_map(di->bas.bst, addr, uart_getrange(class), 0, 322 &di->bas.bsh); 323 return (error); 324 inval: 325 printf("warning: bad uart specification: %s\n", cp); 326 freeenv(cp); 327 return (EINVAL); 328 } 329