1 /*- 2 * SPDX-License-Identifier: BSD-2-Clause 3 * 4 * Copyright (c) 2009-2010 The FreeBSD Foundation 5 * 6 * This software was developed by Semihalf under sponsorship from 7 * the FreeBSD Foundation. 8 * 9 * Redistribution and use in source and binary forms, with or without 10 * modification, are permitted provided that the following conditions 11 * are met: 12 * 1. Redistributions of source code must retain the above copyright 13 * notice, this list of conditions and the following disclaimer. 14 * 2. Redistributions in binary form must reproduce the above copyright 15 * notice, this list of conditions and the following disclaimer in the 16 * documentation and/or other materials provided with the distribution. 17 * 18 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 19 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 20 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 21 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 22 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 23 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 24 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 25 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 26 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 27 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 28 * SUCH DAMAGE. 29 */ 30 31 #include <sys/cdefs.h> 32 #include "opt_platform.h" 33 34 #include <sys/param.h> 35 #include <sys/systm.h> 36 #include <sys/bus.h> 37 #include <sys/kernel.h> 38 #include <sys/module.h> 39 40 #include <machine/bus.h> 41 42 #include <dev/fdt/fdt_common.h> 43 #include <dev/ofw/ofw_bus.h> 44 #include <dev/ofw/ofw_bus_subr.h> 45 #include <dev/uart/uart.h> 46 #include <dev/uart/uart_bus.h> 47 #include <dev/uart/uart_cpu.h> 48 #include <dev/uart/uart_cpu_fdt.h> 49 50 static int uart_fdt_probe(device_t); 51 52 static device_method_t uart_fdt_methods[] = { 53 /* Device interface */ 54 DEVMETHOD(device_probe, uart_fdt_probe), 55 DEVMETHOD(device_attach, uart_bus_attach), 56 DEVMETHOD(device_detach, uart_bus_detach), 57 { 0, 0 } 58 }; 59 60 static driver_t uart_fdt_driver = { 61 uart_driver_name, 62 uart_fdt_methods, 63 sizeof(struct uart_softc), 64 }; 65 66 int 67 uart_fdt_get_clock(phandle_t node, pcell_t *cell) 68 { 69 70 /* clock-frequency is a FreeBSD-only extension. */ 71 if ((OF_getencprop(node, "clock-frequency", cell, 72 sizeof(*cell))) <= 0) { 73 /* Try to retrieve parent 'bus-frequency' */ 74 /* XXX this should go to simple-bus fixup or so */ 75 if ((OF_getencprop(OF_parent(node), "bus-frequency", cell, 76 sizeof(*cell))) <= 0) 77 *cell = 0; 78 } 79 80 return (0); 81 } 82 83 int 84 uart_fdt_get_shift(phandle_t node, pcell_t *cell) 85 { 86 87 if ((OF_getencprop(node, "reg-shift", cell, sizeof(*cell))) <= 0) 88 return (-1); 89 return (0); 90 } 91 92 int 93 uart_fdt_get_io_width(phandle_t node, pcell_t *cell) 94 { 95 96 if ((OF_getencprop(node, "reg-io-width", cell, sizeof(*cell))) <= 0) 97 return (-1); 98 return (0); 99 } 100 101 static uintptr_t 102 uart_fdt_find_device(device_t dev) 103 { 104 struct ofw_compat_data **cd; 105 const struct ofw_compat_data *ocd; 106 107 SET_FOREACH(cd, uart_fdt_class_and_device_set) { 108 ocd = ofw_bus_search_compatible(dev, *cd); 109 if (ocd->ocd_data != 0) 110 return (ocd->ocd_data); 111 } 112 return (0); 113 } 114 115 static int 116 phandle_chosen_propdev(phandle_t chosen, const char *name, phandle_t *node) 117 { 118 char buf[64]; 119 char *sep; 120 121 if (OF_getprop(chosen, name, buf, sizeof(buf)) <= 0) 122 return (ENXIO); 123 /* 124 * stdout-path may have a ':' to separate the device from the 125 * connection settings. Split the string so we just pass the former 126 * to OF_finddevice. 127 */ 128 sep = strchr(buf, ':'); 129 if (sep != NULL) 130 *sep = '\0'; 131 if ((*node = OF_finddevice(buf)) == -1) 132 return (ENXIO); 133 134 return (0); 135 } 136 137 static const struct ofw_compat_data * 138 uart_fdt_find_compatible(phandle_t node, const struct ofw_compat_data *cd) 139 { 140 const struct ofw_compat_data *ocd; 141 142 for (ocd = cd; ocd->ocd_str != NULL; ocd++) { 143 if (ofw_bus_node_is_compatible(node, ocd->ocd_str)) 144 return (ocd); 145 } 146 return (NULL); 147 } 148 149 static uintptr_t 150 uart_fdt_find_by_node(phandle_t node, int class_list) 151 { 152 struct ofw_compat_data **cd; 153 const struct ofw_compat_data *ocd; 154 155 if (class_list) { 156 SET_FOREACH(cd, uart_fdt_class_set) { 157 ocd = uart_fdt_find_compatible(node, *cd); 158 if ((ocd != NULL) && (ocd->ocd_data != 0)) 159 return (ocd->ocd_data); 160 } 161 } else { 162 SET_FOREACH(cd, uart_fdt_class_and_device_set) { 163 ocd = uart_fdt_find_compatible(node, *cd); 164 if ((ocd != NULL) && (ocd->ocd_data != 0)) 165 return (ocd->ocd_data); 166 } 167 } 168 169 return (0); 170 } 171 172 int 173 uart_cpu_fdt_probe(struct uart_class **classp, bus_space_tag_t *bst, 174 bus_space_handle_t *bsh, int *baud, u_int *rclk, u_int *shiftp, 175 u_int *iowidthp, const int devtype) 176 { 177 const char *propnames[] = {"stdout-path", "linux,stdout-path", "stdout", 178 "stdin-path", "stdin", NULL}; 179 const char *propnames_dbgport[] = {"freebsd,debug-path", NULL}; 180 const char **name; 181 struct uart_class *class; 182 phandle_t node, chosen; 183 pcell_t br, clk, shift, iowidth; 184 char *cp = NULL; 185 int err; 186 187 /* Has the user forced a specific device node? */ 188 switch (devtype) { 189 case UART_DEV_DBGPORT: 190 cp = kern_getenv("hw.fdt.dbgport"); 191 name = propnames_dbgport; 192 break; 193 case UART_DEV_CONSOLE: 194 cp = kern_getenv("hw.fdt.console"); 195 name = propnames; 196 break; 197 default: 198 return (ENXIO); 199 } 200 201 if (cp == NULL) { 202 /* 203 * Retrieve a node from /chosen. 204 */ 205 node = -1; 206 if ((chosen = OF_finddevice("/chosen")) != -1) { 207 for (; *name != NULL; name++) { 208 if (phandle_chosen_propdev(chosen, *name, 209 &node) == 0) 210 break; 211 } 212 } 213 if (chosen == -1 || *name == NULL) 214 node = OF_finddevice("serial0"); /* Last ditch */ 215 } else { 216 node = OF_finddevice(cp); 217 } 218 219 if (node == -1) 220 return (ENXIO); 221 222 /* 223 * Check old style of UART definition first. Unfortunately, the common 224 * FDT processing is not possible if we have clock, power domains and 225 * pinmux stuff. 226 */ 227 class = (struct uart_class *)uart_fdt_find_by_node(node, 0); 228 if (class != NULL) { 229 if ((err = uart_fdt_get_clock(node, &clk)) != 0) 230 return (err); 231 } else { 232 /* Check class only linker set */ 233 class = 234 (struct uart_class *)uart_fdt_find_by_node(node, 1); 235 if (class == NULL) 236 return (ENXIO); 237 clk = 0; 238 } 239 240 /* 241 * Retrieve serial attributes. 242 */ 243 if (uart_fdt_get_shift(node, &shift) != 0) 244 shift = uart_getregshift(class); 245 246 if (uart_fdt_get_io_width(node, &iowidth) != 0) 247 iowidth = uart_getregiowidth(class); 248 249 if (OF_getencprop(node, "current-speed", &br, sizeof(br)) <= 0) 250 br = 0; 251 252 err = OF_decode_addr(node, 0, bst, bsh, NULL); 253 if (err != 0) 254 return (err); 255 256 *classp = class; 257 *baud = br; 258 *rclk = clk; 259 *shiftp = shift; 260 *iowidthp = iowidth; 261 262 return (0); 263 } 264 265 static int 266 uart_fdt_probe(device_t dev) 267 { 268 struct uart_softc *sc; 269 phandle_t node; 270 pcell_t clock, shift, iowidth; 271 int err; 272 273 sc = device_get_softc(dev); 274 275 if (!ofw_bus_status_okay(dev)) 276 return (ENXIO); 277 278 sc->sc_class = (struct uart_class *)uart_fdt_find_device(dev); 279 if (sc->sc_class == NULL) 280 return (ENXIO); 281 282 node = ofw_bus_get_node(dev); 283 284 if ((err = uart_fdt_get_clock(node, &clock)) != 0) 285 return (err); 286 if (uart_fdt_get_shift(node, &shift) != 0) 287 shift = uart_getregshift(sc->sc_class); 288 if (uart_fdt_get_io_width(node, &iowidth) != 0) 289 iowidth = uart_getregiowidth(sc->sc_class); 290 291 return (uart_bus_probe(dev, (int)shift, (int)iowidth, (int)clock, 0, 0, 0)); 292 } 293 294 DRIVER_MODULE(uart, simplebus, uart_fdt_driver, 0, 0); 295 DRIVER_MODULE(uart, ofwbus, uart_fdt_driver, 0, 0); 296