imx23_rtc.c revision 1.1.2.2
1 1.1.2.2 skrll /* $Id: imx23_rtc.c,v 1.1.2.2 2015/04/06 15:17:52 skrll Exp $ */ 2 1.1.2.2 skrll 3 1.1.2.2 skrll /* 4 1.1.2.2 skrll * Copyright (c) 2014 The NetBSD Foundation, Inc. 5 1.1.2.2 skrll * All rights reserved. 6 1.1.2.2 skrll * 7 1.1.2.2 skrll * This code is derived from software contributed to The NetBSD Foundation 8 1.1.2.2 skrll * by Petri Laakso. 9 1.1.2.2 skrll * 10 1.1.2.2 skrll * Redistribution and use in source and binary forms, with or without 11 1.1.2.2 skrll * modification, are permitted provided that the following conditions 12 1.1.2.2 skrll * are met: 13 1.1.2.2 skrll * 1. Redistributions of source code must retain the above copyright 14 1.1.2.2 skrll * notice, this list of conditions and the following disclaimer. 15 1.1.2.2 skrll * 2. Redistributions in binary form must reproduce the above copyright 16 1.1.2.2 skrll * notice, this list of conditions and the following disclaimer in the 17 1.1.2.2 skrll * documentation and/or other materials provided with the distribution. 18 1.1.2.2 skrll * 19 1.1.2.2 skrll * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS 20 1.1.2.2 skrll * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED 21 1.1.2.2 skrll * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 22 1.1.2.2 skrll * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS 23 1.1.2.2 skrll * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 24 1.1.2.2 skrll * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 25 1.1.2.2 skrll * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 26 1.1.2.2 skrll * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 27 1.1.2.2 skrll * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 28 1.1.2.2 skrll * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 29 1.1.2.2 skrll * POSSIBILITY OF SUCH DAMAGE. 30 1.1.2.2 skrll */ 31 1.1.2.2 skrll 32 1.1.2.2 skrll #include <sys/param.h> 33 1.1.2.2 skrll #include <sys/types.h> 34 1.1.2.2 skrll #include <sys/bus.h> 35 1.1.2.2 skrll #include <sys/cdefs.h> 36 1.1.2.2 skrll #include <sys/device.h> 37 1.1.2.2 skrll #include <sys/errno.h> 38 1.1.2.2 skrll 39 1.1.2.2 skrll #include <arm/imx/imx23_rtcreg.h> 40 1.1.2.2 skrll #include <arm/imx/imx23_rtcvar.h> 41 1.1.2.2 skrll #include <arm/imx/imx23var.h> 42 1.1.2.2 skrll 43 1.1.2.2 skrll typedef struct rtc_softc { 44 1.1.2.2 skrll device_t sc_dev; 45 1.1.2.2 skrll bus_space_tag_t sc_iot; 46 1.1.2.2 skrll bus_space_handle_t sc_hdl; 47 1.1.2.2 skrll } *rtc_softc_t; 48 1.1.2.2 skrll 49 1.1.2.2 skrll static int rtc_match(device_t, cfdata_t, void *); 50 1.1.2.2 skrll static void rtc_attach(device_t, device_t, void *); 51 1.1.2.2 skrll static int rtc_activate(device_t, enum devact); 52 1.1.2.2 skrll 53 1.1.2.2 skrll static void rtc_init(struct rtc_softc *); 54 1.1.2.2 skrll static void rtc_reset(struct rtc_softc *); 55 1.1.2.2 skrll 56 1.1.2.2 skrll static rtc_softc_t _sc = NULL; 57 1.1.2.2 skrll 58 1.1.2.2 skrll CFATTACH_DECL3_NEW(rtc, 59 1.1.2.2 skrll sizeof(struct rtc_softc), 60 1.1.2.2 skrll rtc_match, 61 1.1.2.2 skrll rtc_attach, 62 1.1.2.2 skrll NULL, 63 1.1.2.2 skrll rtc_activate, 64 1.1.2.2 skrll NULL, 65 1.1.2.2 skrll NULL, 66 1.1.2.2 skrll 0 67 1.1.2.2 skrll ); 68 1.1.2.2 skrll 69 1.1.2.2 skrll #define RTC_RD(sc, reg) \ 70 1.1.2.2 skrll bus_space_read_4(sc->sc_iot, sc->sc_hdl, (reg)) 71 1.1.2.2 skrll #define RTC_WR(sc, reg, val) \ 72 1.1.2.2 skrll bus_space_write_4(sc->sc_iot, sc->sc_hdl, (reg), (val)) 73 1.1.2.2 skrll 74 1.1.2.2 skrll #define RTC_SOFT_RST_LOOP 455 /* At least 1 us ... */ 75 1.1.2.2 skrll 76 1.1.2.2 skrll static int 77 1.1.2.2 skrll rtc_match(device_t parent, cfdata_t match, void *aux) 78 1.1.2.2 skrll { 79 1.1.2.2 skrll struct apb_attach_args *aa = aux; 80 1.1.2.2 skrll 81 1.1.2.2 skrll if ((aa->aa_addr == HW_RTC_BASE) && 82 1.1.2.2 skrll (aa->aa_size == HW_RTC_BASE_SIZE)) 83 1.1.2.2 skrll return 1; 84 1.1.2.2 skrll 85 1.1.2.2 skrll return 0; 86 1.1.2.2 skrll } 87 1.1.2.2 skrll 88 1.1.2.2 skrll static void 89 1.1.2.2 skrll rtc_attach(device_t parent, device_t self, void *aux) 90 1.1.2.2 skrll { 91 1.1.2.2 skrll struct rtc_softc *sc = device_private(self); 92 1.1.2.2 skrll struct apb_attach_args *aa = aux; 93 1.1.2.2 skrll static int rtc_attached = 0; 94 1.1.2.2 skrll 95 1.1.2.2 skrll sc->sc_dev = self; 96 1.1.2.2 skrll sc->sc_iot = aa->aa_iot; 97 1.1.2.2 skrll 98 1.1.2.2 skrll if (rtc_attached) { 99 1.1.2.2 skrll aprint_error_dev(sc->sc_dev, "rtc is already attached\n"); 100 1.1.2.2 skrll return; 101 1.1.2.2 skrll } 102 1.1.2.2 skrll 103 1.1.2.2 skrll if (bus_space_map(sc->sc_iot, aa->aa_addr, aa->aa_size, 0, 104 1.1.2.2 skrll &sc->sc_hdl)) 105 1.1.2.2 skrll { 106 1.1.2.2 skrll aprint_error_dev(sc->sc_dev, "Unable to map bus space\n"); 107 1.1.2.2 skrll return; 108 1.1.2.2 skrll } 109 1.1.2.2 skrll 110 1.1.2.2 skrll 111 1.1.2.2 skrll rtc_init(sc); 112 1.1.2.2 skrll rtc_reset(sc); 113 1.1.2.2 skrll 114 1.1.2.2 skrll aprint_normal("\n"); 115 1.1.2.2 skrll 116 1.1.2.2 skrll rtc_attached = 1; 117 1.1.2.2 skrll 118 1.1.2.2 skrll return; 119 1.1.2.2 skrll } 120 1.1.2.2 skrll 121 1.1.2.2 skrll static int 122 1.1.2.2 skrll rtc_activate(device_t self, enum devact act) 123 1.1.2.2 skrll { 124 1.1.2.2 skrll 125 1.1.2.2 skrll return EOPNOTSUPP; 126 1.1.2.2 skrll } 127 1.1.2.2 skrll 128 1.1.2.2 skrll static void 129 1.1.2.2 skrll rtc_init(struct rtc_softc *sc) 130 1.1.2.2 skrll { 131 1.1.2.2 skrll _sc = sc; 132 1.1.2.2 skrll return; 133 1.1.2.2 skrll } 134 1.1.2.2 skrll 135 1.1.2.2 skrll /* 136 1.1.2.2 skrll * Remove pulldown resistors on the headphone outputs. 137 1.1.2.2 skrll */ 138 1.1.2.2 skrll void 139 1.1.2.2 skrll rtc_release_gnd(int val) 140 1.1.2.2 skrll { 141 1.1.2.2 skrll struct rtc_softc *sc = _sc; 142 1.1.2.2 skrll 143 1.1.2.2 skrll if (sc == NULL) { 144 1.1.2.2 skrll aprint_error("rtc is not initalized"); 145 1.1.2.2 skrll return; 146 1.1.2.2 skrll } 147 1.1.2.2 skrll if(val) 148 1.1.2.2 skrll RTC_WR(sc, HW_RTC_PERSISTENT0_SET, (1<<19)); 149 1.1.2.2 skrll else 150 1.1.2.2 skrll RTC_WR(sc, HW_RTC_PERSISTENT0_CLR, (1<<19)); 151 1.1.2.2 skrll 152 1.1.2.2 skrll return; 153 1.1.2.2 skrll } 154 1.1.2.2 skrll 155 1.1.2.2 skrll /* 156 1.1.2.2 skrll * Reset the RTC block. 157 1.1.2.2 skrll * 158 1.1.2.2 skrll * Inspired by i.MX23 RM "39.3.10 Correct Way to Soft Reset a Block" 159 1.1.2.2 skrll */ 160 1.1.2.2 skrll static void 161 1.1.2.2 skrll rtc_reset(struct rtc_softc *sc) 162 1.1.2.2 skrll { 163 1.1.2.2 skrll unsigned int loop; 164 1.1.2.2 skrll 165 1.1.2.2 skrll /* Prepare for soft-reset by making sure that SFTRST is not currently 166 1.1.2.2 skrll * asserted. Also clear CLKGATE so we can wait for its assertion below. 167 1.1.2.2 skrll */ 168 1.1.2.2 skrll RTC_WR(sc, HW_RTC_CTRL_CLR, HW_RTC_CTRL_SFTRST); 169 1.1.2.2 skrll 170 1.1.2.2 skrll /* Wait at least a microsecond for SFTRST to deassert. */ 171 1.1.2.2 skrll loop = 0; 172 1.1.2.2 skrll while ((RTC_RD(sc, HW_RTC_CTRL) & HW_RTC_CTRL_SFTRST) || 173 1.1.2.2 skrll (loop < RTC_SOFT_RST_LOOP)) 174 1.1.2.2 skrll loop++; 175 1.1.2.2 skrll 176 1.1.2.2 skrll /* Clear CLKGATE so we can wait for its assertion below. */ 177 1.1.2.2 skrll RTC_WR(sc, HW_RTC_CTRL_CLR, HW_RTC_CTRL_CLKGATE); 178 1.1.2.2 skrll 179 1.1.2.2 skrll /* Soft-reset the block. */ 180 1.1.2.2 skrll RTC_WR(sc, HW_RTC_CTRL_SET, HW_RTC_CTRL_SFTRST); 181 1.1.2.2 skrll 182 1.1.2.2 skrll /* Wait until clock is in the gated state. */ 183 1.1.2.2 skrll while (!(RTC_RD(sc, HW_RTC_CTRL) & HW_RTC_CTRL_CLKGATE)); 184 1.1.2.2 skrll 185 1.1.2.2 skrll /* Bring block out of reset. */ 186 1.1.2.2 skrll RTC_WR(sc, HW_RTC_CTRL_CLR, HW_RTC_CTRL_SFTRST); 187 1.1.2.2 skrll 188 1.1.2.2 skrll loop = 0; 189 1.1.2.2 skrll while ((RTC_RD(sc, HW_RTC_CTRL) & HW_RTC_CTRL_SFTRST) || 190 1.1.2.2 skrll (loop < RTC_SOFT_RST_LOOP)) 191 1.1.2.2 skrll loop++; 192 1.1.2.2 skrll 193 1.1.2.2 skrll RTC_WR(sc, HW_RTC_CTRL_CLR, HW_RTC_CTRL_CLKGATE); 194 1.1.2.2 skrll 195 1.1.2.2 skrll /* Wait until clock is in the NON-gated state. */ 196 1.1.2.2 skrll while (RTC_RD(sc, HW_RTC_CTRL) & HW_RTC_CTRL_CLKGATE); 197 1.1.2.2 skrll 198 1.1.2.2 skrll return; 199 1.1.2.2 skrll } 200
Indexes created Tue Sep 30 17:09:57 GMT 2025