1 /* 2 * Copyright (c) 2010 3 * Ben Gray <ben.r.gray@gmail.com>. 4 * All rights reserved. 5 * 6 * Redistribution and use in source and binary forms, with or without 7 * modification, are permitted provided that the following conditions 8 * are met: 9 * 1. Redistributions of source code must retain the above copyright 10 * notice, this list of conditions and the following disclaimer. 11 * 2. Redistributions in binary form must reproduce the above copyright 12 * notice, this list of conditions and the following disclaimer in the 13 * documentation and/or other materials provided with the distribution. 14 * 3. All advertising materials mentioning features or use of this software 15 * must display the following acknowledgement: 16 * This product includes software developed by Ben Gray. 17 * 4. The name of the company nor the name of the author may be used to 18 * endorse or promote products derived from this software without specific 19 * prior written permission. 20 * 21 * THIS SOFTWARE IS PROVIDED BY BEN GRAY ``AS IS'' AND ANY EXPRESS OR 22 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 23 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 24 * IN NO EVENT SHALL BEN GRAY BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, 25 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, 26 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; 27 * OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, 28 * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR 29 * OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF 30 * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 31 */ 32 33 /** 34 * SCM - System Control Module 35 * 36 * Hopefully in the end this module will contain a bunch of utility functions 37 * for configuring and querying the general system control registers, but for 38 * now it only does pin(pad) multiplexing. 39 * 40 * This is different from the GPIO module in that it is used to configure the 41 * pins between modules not just GPIO input/output. 42 * 43 * This file contains the generic top level driver, however it relies on chip 44 * specific settings and therefore expects an array of ti_scm_padconf structs 45 * call ti_padconf_devmap to be located somewhere in the kernel. 46 * 47 */ 48 #include <sys/cdefs.h> 49 __FBSDID("$FreeBSD$"); 50 51 #include <sys/param.h> 52 #include <sys/systm.h> 53 #include <sys/kernel.h> 54 #include <sys/module.h> 55 #include <sys/bus.h> 56 #include <sys/resource.h> 57 #include <sys/rman.h> 58 #include <sys/lock.h> 59 #include <sys/mutex.h> 60 61 #include <machine/bus.h> 62 #include <machine/resource.h> 63 64 #include <dev/ofw/openfirm.h> 65 #include <dev/ofw/ofw_bus.h> 66 #include <dev/ofw/ofw_bus_subr.h> 67 #include <dev/fdt/fdt_pinctrl.h> 68 69 #include "ti_scm.h" 70 71 static struct resource_spec ti_scm_res_spec[] = { 72 { SYS_RES_MEMORY, 0, RF_ACTIVE }, /* Control memory window */ 73 { -1, 0 } 74 }; 75 76 static struct ti_scm_softc *ti_scm_sc; 77 78 #define ti_scm_read_4(sc, reg) \ 79 bus_space_read_4((sc)->sc_bst, (sc)->sc_bsh, (reg)) 80 #define ti_scm_write_4(sc, reg, val) \ 81 bus_space_write_4((sc)->sc_bst, (sc)->sc_bsh, (reg), (val)) 82 83 /* 84 * Device part of OMAP SCM driver 85 */ 86 static int 87 ti_scm_probe(device_t dev) 88 { 89 if (!ofw_bus_status_okay(dev)) 90 return (ENXIO); 91 92 if (!ofw_bus_is_compatible(dev, "syscon")) 93 return (ENXIO); 94 95 if (ti_scm_sc) { 96 return (EEXIST); 97 } 98 99 device_set_desc(dev, "TI Control Module"); 100 return (BUS_PROBE_DEFAULT); 101 } 102 103 /** 104 * ti_scm_attach - attaches the timer to the simplebus 105 * @dev: new device 106 * 107 * Reserves memory and interrupt resources, stores the softc structure 108 * globally and registers both the timecount and eventtimer objects. 109 * 110 * RETURNS 111 * Zero on success or ENXIO if an error occuried. 112 */ 113 static int 114 ti_scm_attach(device_t dev) 115 { 116 struct ti_scm_softc *sc = device_get_softc(dev); 117 118 sc->sc_dev = dev; 119 120 if (bus_alloc_resources(dev, ti_scm_res_spec, sc->sc_res)) { 121 device_printf(dev, "could not allocate resources\n"); 122 return (ENXIO); 123 } 124 125 /* Global timer interface */ 126 sc->sc_bst = rman_get_bustag(sc->sc_res[0]); 127 sc->sc_bsh = rman_get_bushandle(sc->sc_res[0]); 128 129 ti_scm_sc = sc; 130 131 /* Attach platform extensions, if any. */ 132 bus_generic_probe(dev); 133 134 return (bus_generic_attach(dev)); 135 } 136 137 int 138 ti_scm_reg_read_4(uint32_t reg, uint32_t *val) 139 { 140 if (!ti_scm_sc) 141 return (ENXIO); 142 143 *val = ti_scm_read_4(ti_scm_sc, reg); 144 return (0); 145 } 146 147 int 148 ti_scm_reg_write_4(uint32_t reg, uint32_t val) 149 { 150 if (!ti_scm_sc) 151 return (ENXIO); 152 153 ti_scm_write_4(ti_scm_sc, reg, val); 154 return (0); 155 } 156 157 158 static device_method_t ti_scm_methods[] = { 159 DEVMETHOD(device_probe, ti_scm_probe), 160 DEVMETHOD(device_attach, ti_scm_attach), 161 162 { 0, 0 } 163 }; 164 165 static driver_t ti_scm_driver = { 166 "ti_scm", 167 ti_scm_methods, 168 sizeof(struct ti_scm_softc), 169 }; 170 171 static devclass_t ti_scm_devclass; 172 173 EARLY_DRIVER_MODULE(ti_scm, simplebus, ti_scm_driver, ti_scm_devclass, 0, 0, 174 BUS_PASS_BUS + BUS_PASS_ORDER_MIDDLE); 175