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