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 <sys/param.h> 34 #include <sys/bus.h> 35 #include <sys/kernel.h> 36 #include <sys/module.h> 37 38 #include <machine/bus.h> 39 #include <machine/fdt.h> 40 41 #include <dev/fdt/fdt_common.h> 42 #include <dev/ofw/ofw_bus.h> 43 #include <dev/ofw/ofw_bus_subr.h> 44 #include <dev/uart/uart.h> 45 #include <dev/uart/uart_bus.h> 46 #include <dev/uart/uart_cpu.h> 47 48 static int uart_fdt_probe(device_t); 49 50 static device_method_t uart_fdt_methods[] = { 51 /* Device interface */ 52 DEVMETHOD(device_probe, uart_fdt_probe), 53 DEVMETHOD(device_attach, uart_bus_attach), 54 DEVMETHOD(device_detach, uart_bus_detach), 55 { 0, 0 } 56 }; 57 58 static driver_t uart_fdt_driver = { 59 uart_driver_name, 60 uart_fdt_methods, 61 sizeof(struct uart_softc), 62 }; 63 64 static int 65 uart_fdt_get_clock(phandle_t node, pcell_t *cell) 66 { 67 pcell_t clock; 68 69 if ((OF_getprop(node, "clock-frequency", &clock, 70 sizeof(clock))) <= 0) 71 return (ENXIO); 72 73 if (clock == 0) 74 /* Try to retrieve parent 'bus-frequency' */ 75 /* XXX this should go to simple-bus fixup or so */ 76 if ((OF_getprop(OF_parent(node), "bus-frequency", &clock, 77 sizeof(clock))) <= 0) 78 clock = 0; 79 80 *cell = fdt32_to_cpu(clock); 81 return (0); 82 } 83 84 static int 85 uart_fdt_get_shift(phandle_t node, pcell_t *cell) 86 { 87 pcell_t shift; 88 89 if ((OF_getprop(node, "reg-shift", &shift, sizeof(shift))) <= 0) 90 shift = 0; 91 *cell = fdt32_to_cpu(shift); 92 return (0); 93 } 94 95 static int 96 uart_fdt_probe(device_t dev) 97 { 98 struct uart_softc *sc; 99 phandle_t node; 100 pcell_t clock, shift; 101 int err; 102 103 if (!ofw_bus_is_compatible(dev, "ns16550")) 104 return (ENXIO); 105 106 sc = device_get_softc(dev); 107 sc->sc_class = &uart_ns8250_class; 108 109 node = ofw_bus_get_node(dev); 110 111 if ((err = uart_fdt_get_clock(node, &clock)) != 0) 112 return (err); 113 uart_fdt_get_shift(node, &shift); 114 115 return (uart_bus_probe(dev, (int)shift, (int)clock, 0, 0)); 116 } 117 118 DRIVER_MODULE(uart, simplebus, uart_fdt_driver, uart_devclass, 0, 0); 119 120 /* 121 * UART console routines. 122 */ 123 bus_space_tag_t uart_bus_space_io; 124 bus_space_tag_t uart_bus_space_mem; 125 126 int 127 uart_cpu_eqres(struct uart_bas *b1, struct uart_bas *b2) 128 { 129 130 return ((b1->bsh == b2->bsh && b1->bst == b2->bst) ? 1 : 0); 131 } 132 133 int 134 uart_cpu_getdev(int devtype, struct uart_devinfo *di) 135 { 136 char buf[64]; 137 struct uart_class *class; 138 phandle_t node, chosen; 139 pcell_t shift, br, rclk; 140 u_long start, size; 141 int err; 142 143 if (devtype != UART_DEV_CONSOLE) 144 return (ENXIO); 145 146 /* 147 * Retrieve /chosen/std{in,out}. 148 */ 149 if ((chosen = OF_finddevice("/chosen")) == 0) 150 return (ENXIO); 151 if (OF_getprop(chosen, "stdin", buf, sizeof(buf)) <= 0) 152 return (ENXIO); 153 if ((node = OF_finddevice(buf)) == 0) 154 return (ENXIO); 155 if (OF_getprop(chosen, "stdout", buf, sizeof(buf)) <= 0) 156 return (ENXIO); 157 if (OF_finddevice(buf) != node) 158 /* Only stdin == stdout is supported. */ 159 return (ENXIO); 160 /* 161 * Retrieve serial attributes. 162 */ 163 uart_fdt_get_shift(node, &shift); 164 165 if (OF_getprop(node, "current-speed", &br, sizeof(br)) <= 0) 166 br = 0; 167 br = fdt32_to_cpu(br); 168 169 if ((err = uart_fdt_get_clock(node, &rclk)) != 0) 170 return (err); 171 /* 172 * Finalize configuration. 173 */ 174 class = &uart_quicc_class; 175 if (fdt_is_compatible(node, "ns16550")) 176 class = &uart_ns8250_class; 177 178 di->bas.chan = 0; 179 di->bas.regshft = (u_int)shift; 180 di->baudrate = 0; 181 di->bas.rclk = (u_int)rclk; 182 di->ops = uart_getops(class); 183 di->databits = 8; 184 di->stopbits = 1; 185 di->parity = UART_PARITY_NONE; 186 di->bas.bst = fdtbus_bs_tag; 187 188 err = fdt_regsize(node, &start, &size); 189 if (err) 190 return (ENXIO); 191 start += fdt_immr_va; 192 193 uart_bus_space_mem = fdtbus_bs_tag; 194 uart_bus_space_io = NULL; 195 196 if (bus_space_map(di->bas.bst, start, size, 0, &di->bas.bsh) != 0) 197 return (ENXIO); 198 199 return (0); 200 } 201