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