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: stable/11/sys/dev/uart/uart_bus_fdt.c 340145 2018-11-04 23:28:56Z mmacy $"); 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 51static int uart_fdt_probe(device_t); 52 53static 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 61static driver_t uart_fdt_driver = { 62 uart_driver_name, 63 uart_fdt_methods, 64 sizeof(struct uart_softc), 65}; 66 67int 68uart_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 84int 85uart_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 93int 94uart_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 102static uintptr_t 103uart_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 116static int 117phandle_chosen_propdev(phandle_t chosen, const char *name, phandle_t *node) 118{ 119 char buf[64]; 120 121 if (OF_getprop(chosen, name, buf, sizeof(buf)) <= 0) 122 return (ENXIO); 123 if ((*node = OF_finddevice(buf)) == -1) 124 return (ENXIO); 125 126 return (0); 127} 128 129static const struct ofw_compat_data * 130uart_fdt_find_compatible(phandle_t node, const struct ofw_compat_data *cd) 131{ 132 const struct ofw_compat_data *ocd; 133 134 for (ocd = cd; ocd->ocd_str != NULL; ocd++) { 135 if (ofw_bus_node_is_compatible(node, ocd->ocd_str)) 136 return (ocd); 137 } 138 return (NULL); 139} 140 141static uintptr_t 142uart_fdt_find_by_node(phandle_t node, int class_list) 143{ 144 struct ofw_compat_data **cd; 145 const struct ofw_compat_data *ocd; 146 147 if (class_list) { 148 SET_FOREACH(cd, uart_fdt_class_set) { 149 ocd = uart_fdt_find_compatible(node, *cd); 150 if ((ocd != NULL) && (ocd->ocd_data != 0)) 151 return (ocd->ocd_data); 152 } 153 } else { 154 SET_FOREACH(cd, uart_fdt_class_and_device_set) { 155 ocd = uart_fdt_find_compatible(node, *cd); 156 if ((ocd != NULL) && (ocd->ocd_data != 0)) 157 return (ocd->ocd_data); 158 } 159 } 160 161 return (0); 162} 163 164int 165uart_cpu_fdt_probe(struct uart_class **classp, bus_space_tag_t *bst, 166 bus_space_handle_t *bsh, int *baud, u_int *rclk, u_int *shiftp) 167{ 168 const char *propnames[] = {"stdout-path", "linux,stdout-path", "stdout", 169 "stdin-path", "stdin", NULL}; 170 const char **name; 171 struct uart_class *class; 172 phandle_t node, chosen; 173 pcell_t br, clk, shift, iowidth; 174 char *cp; 175 int err; 176 177 /* Has the user forced a specific device node? */ 178 cp = kern_getenv("hw.fdt.console"); 179 if (cp == NULL) { 180 /* 181 * Retrieve /chosen/std{in,out}. 182 */ 183 node = -1; 184 if ((chosen = OF_finddevice("/chosen")) != -1) { 185 for (name = propnames; *name != NULL; name++) { 186 if (phandle_chosen_propdev(chosen, *name, 187 &node) == 0) 188 break; 189 } 190 } 191 if (chosen == -1 || *name == NULL) 192 node = OF_finddevice("serial0"); /* Last ditch */ 193 } else { 194 node = OF_finddevice(cp); 195 } 196 197 if (node == -1) 198 return (ENXIO); 199 200 /* 201 * Check old style of UART definition first. Unfortunately, the common 202 * FDT processing is not possible if we have clock, power domains and 203 * pinmux stuff. 204 */ 205 class = (struct uart_class *)uart_fdt_find_by_node(node, 0); 206 if (class != NULL) { 207 if ((err = uart_fdt_get_clock(node, &clk)) != 0) 208 return (err); 209 } else { 210 /* Check class only linker set */ 211 class = 212 (struct uart_class *)uart_fdt_find_by_node(node, 1); 213 if (class == NULL) 214 return (ENXIO); 215 clk = 0; 216 } 217 218 /* 219 * Retrieve serial attributes. 220 */ 221 if (uart_fdt_get_shift(node, &shift) != 0) 222 shift = uart_getregshift(class); 223 224 if (uart_fdt_get_io_width(node, &iowidth) != 0) 225 iowidth = uart_getregiowidth(class); 226 227 if (OF_getencprop(node, "current-speed", &br, sizeof(br)) <= 0) 228 br = 0; 229 230 err = OF_decode_addr(node, 0, bst, bsh, NULL); 231 if (err != 0) 232 return (err); 233 234 *classp = class; 235 *baud = br; 236 *rclk = clk; 237 *shiftp = shift; 238 239 return (0); 240} 241 242static int 243uart_fdt_probe(device_t dev) 244{ 245 struct uart_softc *sc; 246 phandle_t node; 247 pcell_t clock, shift, iowidth; 248 int err; 249 250 sc = device_get_softc(dev); 251 252 if (!ofw_bus_status_okay(dev)) 253 return (ENXIO); 254 255 sc->sc_class = (struct uart_class *)uart_fdt_find_device(dev); 256 if (sc->sc_class == NULL) 257 return (ENXIO); 258 259 node = ofw_bus_get_node(dev); 260 261 if ((err = uart_fdt_get_clock(node, &clock)) != 0) 262 return (err); 263 if (uart_fdt_get_shift(node, &shift) != 0) 264 shift = uart_getregshift(sc->sc_class); 265 if (uart_fdt_get_io_width(node, &iowidth) != 0) 266 iowidth = uart_getregiowidth(sc->sc_class); 267 268 return (uart_bus_probe(dev, (int)shift, (int)iowidth, (int)clock, 0, 0, 0)); 269} 270 271DRIVER_MODULE(uart, simplebus, uart_fdt_driver, uart_devclass, 0, 0); 272DRIVER_MODULE(uart, ofwbus, uart_fdt_driver, uart_devclass, 0, 0); 273