1 /* $NetBSD: exynos_rtc.c,v 1.2 2015/12/21 04:58:50 marty Exp $ */ 2 3 /*- 4 * Copyright (c) 2015 The NetBSD Foundation, Inc. 5 * All rights reserved. 6 * 7 * This code is derived from software contributed to The NetBSD Foundation 8 * by Marty Fouts 9 * 10 * Redistribution and use in source and binary forms, with or without 11 * modification, are permitted provided that the following conditions 12 * are met: 13 * 1. Redistributions of source code must retain the above copyright 14 * notice, this list of conditions and the following disclaimer. 15 * 2. Redistributions in binary form must reproduce the above copyright 16 * notice, this list of conditions and the following disclaimer in the 17 * documentation and/or other materials provided with the distribution. 18 * 19 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS 20 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED 21 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 22 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS 23 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 24 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 25 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 26 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 27 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 28 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 29 * POSSIBILITY OF SUCH DAMAGE. 30 */ 31 32 #include "opt_exynos.h" 33 #include "opt_arm_debug.h" 34 #include "gpio.h" 35 36 #include <sys/cdefs.h> 37 __KERNEL_RCSID(1, "$NetBSD: exynos_rtc.c,v 1.2 2015/12/21 04:58:50 marty Exp $"); 38 39 #include <sys/param.h> 40 #include <sys/bus.h> 41 #include <sys/device.h> 42 #include <sys/intr.h> 43 #include <sys/systm.h> 44 #include <sys/kernel.h> 45 #include <sys/kmem.h> 46 47 #include <dev/clock_subr.h> 48 49 #include <arm/samsung/exynos_reg.h> 50 #include <arm/samsung/exynos_intr.h> 51 52 #include <dev/fdt/fdtvar.h> 53 54 struct exynos_rtc_softc { 55 device_t sc_dev; 56 bus_space_tag_t sc_bst; 57 bus_space_handle_t sc_bsh; 58 59 struct todr_chip_handle sc_todr; 60 }; 61 62 static int exynos_rtc_match(device_t, cfdata_t, void *); 63 static void exynos_rtc_attach(device_t, device_t, void *); 64 65 static int exynos_rtc_gettime(todr_chip_handle_t, struct timeval *); 66 static int exynos_rtc_settime(todr_chip_handle_t, struct timeval *); 67 68 CFATTACH_DECL_NEW(exynos_rtc, sizeof(struct exynos_rtc_softc), 69 exynos_rtc_match, exynos_rtc_attach, NULL, NULL); 70 71 #define RTC_READ(sc, reg) \ 72 bus_space_read_4((sc)->sc_bst, (sc)->sc_bsh, (reg)) 73 #define RTC_WRITE(sc, reg, val) \ 74 bus_space_write_4((sc)->sc_bst, (sc)->sc_bsh, (reg), (val)) 75 76 static int 77 exynos_rtc_match(device_t parent, cfdata_t cf, void *aux) 78 { 79 const char * const compatible[] = { "samsung,s3c6410-rtc", 80 NULL }; 81 struct fdt_attach_args * const faa = aux; 82 return of_match_compatible(faa->faa_phandle, compatible); 83 } 84 85 static void 86 exynos_rtc_attach(device_t parent, device_t self, void *aux) 87 { 88 struct exynos_rtc_softc * const sc 89 = kmem_zalloc(sizeof(*sc), KM_SLEEP); 90 struct fdt_attach_args * const faa = aux; 91 bus_addr_t addr; 92 bus_size_t size; 93 int error; 94 95 if (fdtbus_get_reg(faa->faa_phandle, 0, &addr, &size) != 0) { 96 aprint_error(": couldn't get registers\n"); 97 return; 98 } 99 100 aprint_normal(" @ 0x%08x", (uint)addr); 101 sc->sc_dev = self; 102 sc->sc_bst = faa->faa_bst; 103 error = bus_space_map(sc->sc_bst, addr, size, 0, &sc->sc_bsh); 104 if (error) { 105 aprint_error(": couldn't map %#llx: %d", 106 (uint64_t)addr, error); 107 return; 108 } 109 110 aprint_naive("\n"); 111 aprint_normal(": RTC\n"); 112 113 sc->sc_todr.todr_gettime = exynos_rtc_gettime; 114 sc->sc_todr.todr_settime = exynos_rtc_settime; 115 sc->sc_todr.cookie = sc; 116 todr_attach(&sc->sc_todr); 117 118 } 119 120 static int 121 exynos_rtc_gettime(todr_chip_handle_t tch, struct timeval *tv) 122 { 123 struct exynos_rtc_softc * const sc = tch->cookie; 124 125 tv->tv_sec = RTC_READ(sc, EXYNOS5_RTC_OFFSET); 126 tv->tv_usec = 0; 127 128 return 0; 129 } 130 131 static int 132 exynos_rtc_settime(todr_chip_handle_t tch, struct timeval *tv) 133 { 134 struct exynos_rtc_softc * const sc = tch->cookie; 135 int retry = 500; 136 137 while (--retry > 0) { 138 if (!RTC_READ(sc, EXYNOS5_RTC_OFFSET)) 139 break; 140 delay(1); 141 } 142 if (retry == 0) { 143 device_printf(sc->sc_dev, "RTC write failed (BUSY)\n"); 144 return ETIMEDOUT; 145 } 146 147 RTC_WRITE(sc, EXYNOS5_RTC_OFFSET, tv->tv_sec); 148 149 return 0; 150 } 151