1 /* $NetBSD: syscon.c,v 1.5 2021/01/27 03:10:21 thorpej Exp $ */ 2 3 /*- 4 * Copyright (c) 2018 Jared McNeill <jmcneill@invisible.ca> 5 * All rights reserved. 6 * 7 * Redistribution and use in source and binary forms, with or without 8 * modification, are permitted provided that the following conditions 9 * are met: 10 * 1. Redistributions of source code must retain the above copyright 11 * notice, this list of conditions and the following disclaimer. 12 * 2. Redistributions in binary form must reproduce the above copyright 13 * notice, this list of conditions and the following disclaimer in the 14 * documentation and/or other materials provided with the distribution. 15 * 16 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 17 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 18 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 19 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, 20 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, 21 * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; 22 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED 23 * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, 24 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 25 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 26 * SUCH DAMAGE. 27 */ 28 29 #include <sys/cdefs.h> 30 __KERNEL_RCSID(0, "$NetBSD: syscon.c,v 1.5 2021/01/27 03:10:21 thorpej Exp $"); 31 32 #include <sys/param.h> 33 #include <sys/bus.h> 34 #include <sys/device.h> 35 #include <sys/systm.h> 36 #include <sys/sysctl.h> 37 #include <sys/kmem.h> 38 #include <sys/gpio.h> 39 40 #include <dev/fdt/fdtvar.h> 41 #include <dev/fdt/syscon.h> 42 43 struct syscon_softc { 44 device_t sc_dev; 45 bus_space_tag_t sc_bst; 46 bus_space_handle_t sc_bsh; 47 kmutex_t sc_lock; 48 49 struct syscon sc_syscon; 50 }; 51 52 static int syscon_match(device_t, cfdata_t, void *); 53 static void syscon_attach(device_t, device_t, void *); 54 55 static const struct device_compatible_entry compat_data[] = { 56 { .compat = "syscon" }, 57 { .compat = "simple-mfd" }, 58 DEVICE_COMPAT_EOL 59 }; 60 61 CFATTACH_DECL_NEW(syscon, sizeof(struct syscon_softc), 62 syscon_match, syscon_attach, NULL, NULL); 63 64 static void 65 syscon_generic_lock(void *priv) 66 { 67 struct syscon_softc * const sc = priv; 68 69 mutex_enter(&sc->sc_lock); 70 } 71 72 static void 73 syscon_generic_unlock(void *priv) 74 { 75 struct syscon_softc * const sc = priv; 76 77 mutex_exit(&sc->sc_lock); 78 } 79 80 static uint32_t 81 syscon_generic_read_4(void *priv, bus_size_t reg) 82 { 83 struct syscon_softc * const sc = priv; 84 85 KASSERT(mutex_owned(&sc->sc_lock)); 86 87 return bus_space_read_4(sc->sc_bst, sc->sc_bsh, reg); 88 } 89 90 static void 91 syscon_generic_write_4(void *priv, bus_size_t reg, uint32_t val) 92 { 93 struct syscon_softc * const sc = priv; 94 95 KASSERT(mutex_owned(&sc->sc_lock)); 96 97 bus_space_write_4(sc->sc_bst, sc->sc_bsh, reg, val); 98 } 99 100 static int 101 syscon_match(device_t parent, cfdata_t cf, void *aux) 102 { 103 struct fdt_attach_args * const faa = aux; 104 105 return of_compatible_match(faa->faa_phandle, compat_data); 106 } 107 108 static void 109 syscon_attach(device_t parent, device_t self, void *aux) 110 { 111 struct syscon_softc * const sc = device_private(self); 112 struct fdt_attach_args * const faa = aux; 113 const int phandle = faa->faa_phandle; 114 bus_addr_t addr; 115 bus_size_t size; 116 int child; 117 118 if (fdtbus_get_reg(phandle, 0, &addr, &size) != 0) { 119 aprint_error(": couldn't get registers\n"); 120 return; 121 } 122 123 sc->sc_dev = self; 124 sc->sc_bst = faa->faa_bst; 125 if (bus_space_map(sc->sc_bst, addr, size, 0, &sc->sc_bsh) != 0) { 126 aprint_error(": couldn't map registers\n"); 127 return; 128 } 129 mutex_init(&sc->sc_lock, MUTEX_DEFAULT, IPL_VM); 130 sc->sc_syscon.priv = sc; 131 sc->sc_syscon.lock = syscon_generic_lock; 132 sc->sc_syscon.unlock = syscon_generic_unlock; 133 sc->sc_syscon.read_4 = syscon_generic_read_4; 134 sc->sc_syscon.write_4 = syscon_generic_write_4; 135 136 aprint_naive("\n"); 137 aprint_normal(": System Controller Registers\n"); 138 139 fdtbus_register_syscon(self, phandle, &sc->sc_syscon); 140 141 fdt_add_bus(self, phandle, faa); 142 143 child = of_find_firstchild_byname(phandle, "clocks"); 144 if (child > 0) 145 fdt_add_bus(self, child, faa); 146 } 147