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/param.h> 30 #include <sys/systm.h> 31 #include <sys/bus.h> 32 33 #include <machine/bus.h> 34 #include <machine/vmparam.h> 35 36 #include <dev/uart/uart.h> 37 #include <dev/uart/uart_cpu.h> 38 39 #define UART_TAG_BR 0 40 #define UART_TAG_CH 1 41 #define UART_TAG_DB 2 42 #define UART_TAG_DT 3 43 #define UART_TAG_IO 4 44 #define UART_TAG_MM 5 45 #define UART_TAG_PA 6 46 #define UART_TAG_RS 7 47 #define UART_TAG_SB 8 48 #define UART_TAG_XO 9 49 #define UART_TAG_BD 10 50 51 static struct uart_class *uart_classes[] = { 52 &uart_ns8250_class, 53 &uart_z8530_class, 54 }; 55 56 static bus_addr_t 57 uart_parse_addr(const char **p) 58 { 59 return (strtoul(*p, (char**)(uintptr_t)p, 0)); 60 } 61 62 static struct uart_class * 63 uart_parse_class(struct uart_class *class, const char **p) 64 { 65 struct uart_class *uc; 66 const char *nm; 67 size_t len; 68 u_int i; 69 70 for (i = 0; i < nitems(uart_classes); i++) { 71 uc = uart_classes[i]; 72 nm = uart_getname(uc); 73 if (nm == NULL || *nm == '\0') 74 continue; 75 len = strlen(nm); 76 if (strncmp(nm, *p, len) == 0) { 77 *p += len; 78 return (uc); 79 } 80 } 81 return (class); 82 } 83 84 static long 85 uart_parse_long(const char **p) 86 { 87 return (strtol(*p, (char**)(uintptr_t)p, 0)); 88 } 89 90 static int 91 uart_parse_parity(const char **p) 92 { 93 if (!strncmp(*p, "even", 4)) { 94 *p += 4; 95 return UART_PARITY_EVEN; 96 } 97 if (!strncmp(*p, "mark", 4)) { 98 *p += 4; 99 return UART_PARITY_MARK; 100 } 101 if (!strncmp(*p, "none", 4)) { 102 *p += 4; 103 return UART_PARITY_NONE; 104 } 105 if (!strncmp(*p, "odd", 3)) { 106 *p += 3; 107 return UART_PARITY_ODD; 108 } 109 if (!strncmp(*p, "space", 5)) { 110 *p += 5; 111 return UART_PARITY_SPACE; 112 } 113 return (-1); 114 } 115 116 static int 117 uart_parse_tag(const char **p) 118 { 119 int tag; 120 121 if ((*p)[0] == 'b' && (*p)[1] == 'd') { 122 tag = UART_TAG_BD; 123 goto out; 124 } 125 if ((*p)[0] == 'b' && (*p)[1] == 'r') { 126 tag = UART_TAG_BR; 127 goto out; 128 } 129 if ((*p)[0] == 'c' && (*p)[1] == 'h') { 130 tag = UART_TAG_CH; 131 goto out; 132 } 133 if ((*p)[0] == 'd' && (*p)[1] == 'b') { 134 tag = UART_TAG_DB; 135 goto out; 136 } 137 if ((*p)[0] == 'd' && (*p)[1] == 't') { 138 tag = UART_TAG_DT; 139 goto out; 140 } 141 if ((*p)[0] == 'i' && (*p)[1] == 'o') { 142 tag = UART_TAG_IO; 143 goto out; 144 } 145 if ((*p)[0] == 'm' && (*p)[1] == 'm') { 146 tag = UART_TAG_MM; 147 goto out; 148 } 149 if ((*p)[0] == 'p' && (*p)[1] == 'a') { 150 tag = UART_TAG_PA; 151 goto out; 152 } 153 if ((*p)[0] == 'r' && (*p)[1] == 's') { 154 tag = UART_TAG_RS; 155 goto out; 156 } 157 if ((*p)[0] == 's' && (*p)[1] == 'b') { 158 tag = UART_TAG_SB; 159 goto out; 160 } 161 if ((*p)[0] == 'x' && (*p)[1] == 'o') { 162 tag = UART_TAG_XO; 163 goto out; 164 } 165 return (-1); 166 167 out: 168 *p += 2; 169 if ((*p)[0] != ':' && (*p)[0] != '=') 170 return (-1); 171 (*p)++; 172 return (tag); 173 } 174 175 /* 176 * Parse a device specification. The specification is a list of attributes 177 * separated by commas. Each attribute is a tag-value pair with the tag and 178 * value separated by a colon. Supported tags are: 179 * 180 * bd = Busy Detect 181 * br = Baudrate 182 * ch = Channel 183 * db = Data bits 184 * dt = Device type 185 * io = I/O port address 186 * mm = Memory mapped I/O address 187 * pa = Parity 188 * rs = Register shift 189 * sb = Stopbits 190 * xo = Device clock (xtal oscillator) 191 * 192 * The io and mm tags are mutually exclusive. 193 */ 194 195 int 196 uart_getenv(int devtype, struct uart_devinfo *di, struct uart_class *class) 197 { 198 const char *spec; 199 char *cp; 200 bus_addr_t addr = ~0U; 201 int error; 202 203 /* 204 * All uart_class references are weak. Make sure the default 205 * device class has been compiled-in. 206 */ 207 if (class == NULL) 208 return (ENXIO); 209 210 /* 211 * Check the environment variables "hw.uart.console" and 212 * "hw.uart.dbgport". These variables, when present, specify 213 * which UART port is to be used as serial console or debug 214 * port (resp). 215 */ 216 switch (devtype) { 217 case UART_DEV_CONSOLE: 218 cp = kern_getenv("hw.uart.console"); 219 break; 220 case UART_DEV_DBGPORT: 221 cp = kern_getenv("hw.uart.dbgport"); 222 break; 223 default: 224 cp = NULL; 225 break; 226 } 227 228 if (cp == NULL) 229 return (ENXIO); 230 231 /* Set defaults. */ 232 di->bas.chan = 0; 233 di->bas.regshft = 0; 234 di->bas.rclk = 0; 235 di->baudrate = 0; 236 di->databits = 8; 237 di->stopbits = 1; 238 di->parity = UART_PARITY_NONE; 239 240 /* Parse the attributes. */ 241 spec = cp; 242 for (;;) { 243 switch (uart_parse_tag(&spec)) { 244 case UART_TAG_BD: 245 di->bas.busy_detect = uart_parse_long(&spec); 246 break; 247 case UART_TAG_BR: 248 di->baudrate = uart_parse_long(&spec); 249 break; 250 case UART_TAG_CH: 251 di->bas.chan = uart_parse_long(&spec); 252 break; 253 case UART_TAG_DB: 254 di->databits = uart_parse_long(&spec); 255 break; 256 case UART_TAG_DT: 257 class = uart_parse_class(class, &spec); 258 break; 259 case UART_TAG_IO: 260 di->bas.bst = uart_bus_space_io; 261 addr = uart_parse_addr(&spec); 262 break; 263 case UART_TAG_MM: 264 di->bas.bst = uart_bus_space_mem; 265 addr = uart_parse_addr(&spec); 266 break; 267 case UART_TAG_PA: 268 di->parity = uart_parse_parity(&spec); 269 break; 270 case UART_TAG_RS: 271 di->bas.regshft = uart_parse_long(&spec); 272 break; 273 case UART_TAG_SB: 274 di->stopbits = uart_parse_long(&spec); 275 break; 276 case UART_TAG_XO: 277 di->bas.rclk = uart_parse_long(&spec); 278 break; 279 default: 280 goto inval; 281 } 282 if (*spec == '\0') 283 break; 284 if (*spec != ',') 285 goto inval; 286 spec++; 287 } 288 289 /* 290 * If we still have an invalid address, the specification must be 291 * missing an I/O port or memory address. We don't like that. 292 */ 293 if (addr == ~0U) 294 goto inval; 295 freeenv(cp); 296 297 /* 298 * Accept only the well-known baudrates. Any invalid baudrate 299 * is silently replaced with a 0-valued baudrate. The 0 baudrate 300 * has special meaning. It means that we're not supposed to 301 * program the baudrate and simply communicate with whatever 302 * speed the hardware is currently programmed for. 303 */ 304 if (di->baudrate >= 19200) { 305 if (di->baudrate % 19200) 306 di->baudrate = 0; 307 } else if (di->baudrate >= 1200) { 308 if (di->baudrate % 1200) 309 di->baudrate = 0; 310 } else if (di->baudrate > 0) { 311 if (di->baudrate % 75) 312 di->baudrate = 0; 313 } else 314 di->baudrate = 0; 315 316 /* Set the ops and create a bus space handle. */ 317 di->ops = uart_getops(class); 318 error = bus_space_map(di->bas.bst, addr, uart_getrange(class), 0, 319 &di->bas.bsh); 320 return (error); 321 inval: 322 printf("warning: bad uart specification: %s\n", cp); 323 freeenv(cp); 324 return (EINVAL); 325 } 326