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 static uintptr_t 94 uart_fdt_find_device(device_t dev) 95 { 96 struct ofw_compat_data **cd; 97 const struct ofw_compat_data *ocd; 98 99 SET_FOREACH(cd, uart_fdt_class_and_device_set) { 100 ocd = ofw_bus_search_compatible(dev, *cd); 101 if (ocd->ocd_data != 0) 102 return (ocd->ocd_data); 103 } 104 return (0); 105 } 106 107 static int 108 phandle_chosen_propdev(phandle_t chosen, const char *name, phandle_t *node) 109 { 110 char buf[64]; 111 112 if (OF_getprop(chosen, name, buf, sizeof(buf)) <= 0) 113 return (ENXIO); 114 if ((*node = OF_finddevice(buf)) == -1) 115 return (ENXIO); 116 117 return (0); 118 } 119 120 static const struct ofw_compat_data * 121 uart_fdt_find_compatible(phandle_t node, const struct ofw_compat_data *cd) 122 { 123 const struct ofw_compat_data *ocd; 124 125 for (ocd = cd; ocd->ocd_str != NULL; ocd++) { 126 if (fdt_is_compatible(node, ocd->ocd_str)) 127 return (ocd); 128 } 129 return (NULL); 130 } 131 132 static uintptr_t 133 uart_fdt_find_by_node(phandle_t node, int class_list) 134 { 135 struct ofw_compat_data **cd; 136 const struct ofw_compat_data *ocd; 137 138 if (class_list) { 139 SET_FOREACH(cd, uart_fdt_class_set) { 140 ocd = uart_fdt_find_compatible(node, *cd); 141 if ((ocd != NULL) && (ocd->ocd_data != 0)) 142 return (ocd->ocd_data); 143 } 144 } else { 145 SET_FOREACH(cd, uart_fdt_class_and_device_set) { 146 ocd = uart_fdt_find_compatible(node, *cd); 147 if ((ocd != NULL) && (ocd->ocd_data != 0)) 148 return (ocd->ocd_data); 149 } 150 } 151 152 return (0); 153 } 154 155 int 156 uart_cpu_fdt_probe(struct uart_class **classp, bus_space_tag_t *bst, 157 bus_space_handle_t *bsh, int *baud, u_int *rclk, u_int *shiftp) 158 { 159 const char *propnames[] = {"stdout-path", "linux,stdout-path", "stdout", 160 "stdin-path", "stdin", NULL}; 161 const char **name; 162 struct uart_class *class; 163 phandle_t node, chosen; 164 pcell_t br, clk, shift; 165 char *cp; 166 int err; 167 168 /* Has the user forced a specific device node? */ 169 cp = kern_getenv("hw.fdt.console"); 170 if (cp == NULL) { 171 /* 172 * Retrieve /chosen/std{in,out}. 173 */ 174 node = -1; 175 if ((chosen = OF_finddevice("/chosen")) != -1) { 176 for (name = propnames; *name != NULL; name++) { 177 if (phandle_chosen_propdev(chosen, *name, 178 &node) == 0) 179 break; 180 } 181 } 182 if (chosen == -1 || *name == NULL) 183 node = OF_finddevice("serial0"); /* Last ditch */ 184 } else { 185 node = OF_finddevice(cp); 186 } 187 188 if (node == -1) 189 return (ENXIO); 190 191 /* 192 * Check old style of UART definition first. Unfortunately, the common 193 * FDT processing is not possible if we have clock, power domains and 194 * pinmux stuff. 195 */ 196 class = (struct uart_class *)uart_fdt_find_by_node(node, 0); 197 if (class != NULL) { 198 if ((err = uart_fdt_get_clock(node, &clk)) != 0) 199 return (err); 200 } else { 201 /* Check class only linker set */ 202 class = 203 (struct uart_class *)uart_fdt_find_by_node(node, 1); 204 if (class == NULL) 205 return (ENXIO); 206 clk = 0; 207 } 208 209 /* 210 * Retrieve serial attributes. 211 */ 212 if (uart_fdt_get_shift(node, &shift) != 0) 213 shift = uart_getregshift(class); 214 215 if (OF_getencprop(node, "current-speed", &br, sizeof(br)) <= 0) 216 br = 0; 217 218 err = OF_decode_addr(node, 0, bst, bsh, NULL); 219 if (err != 0) 220 return (err); 221 222 *classp = class; 223 *baud = br; 224 *rclk = clk; 225 *shiftp = shift; 226 227 return (0); 228 } 229 230 static int 231 uart_fdt_probe(device_t dev) 232 { 233 struct uart_softc *sc; 234 phandle_t node; 235 pcell_t clock, shift; 236 int err; 237 238 sc = device_get_softc(dev); 239 240 if (!ofw_bus_status_okay(dev)) 241 return (ENXIO); 242 243 sc->sc_class = (struct uart_class *)uart_fdt_find_device(dev); 244 if (sc->sc_class == NULL) 245 return (ENXIO); 246 247 node = ofw_bus_get_node(dev); 248 249 if ((err = uart_fdt_get_clock(node, &clock)) != 0) 250 return (err); 251 if (uart_fdt_get_shift(node, &shift) != 0) 252 shift = uart_getregshift(sc->sc_class); 253 254 return (uart_bus_probe(dev, (int)shift, (int)clock, 0, 0)); 255 } 256 257 DRIVER_MODULE(uart, simplebus, uart_fdt_driver, uart_devclass, 0, 0); 258 DRIVER_MODULE(uart, ofwbus, uart_fdt_driver, uart_devclass, 0, 0); 259