imx23_rtc.c revision 1.1.18.2 1 1.1.18.2 jdolecek /* $Id: imx23_rtc.c,v 1.1.18.2 2017/12/03 11:35:53 jdolecek Exp $ */
2 1.1.18.2 jdolecek
3 1.1.18.2 jdolecek /*
4 1.1.18.2 jdolecek * Copyright (c) 2014 The NetBSD Foundation, Inc.
5 1.1.18.2 jdolecek * All rights reserved.
6 1.1.18.2 jdolecek *
7 1.1.18.2 jdolecek * This code is derived from software contributed to The NetBSD Foundation
8 1.1.18.2 jdolecek * by Petri Laakso.
9 1.1.18.2 jdolecek *
10 1.1.18.2 jdolecek * Redistribution and use in source and binary forms, with or without
11 1.1.18.2 jdolecek * modification, are permitted provided that the following conditions
12 1.1.18.2 jdolecek * are met:
13 1.1.18.2 jdolecek * 1. Redistributions of source code must retain the above copyright
14 1.1.18.2 jdolecek * notice, this list of conditions and the following disclaimer.
15 1.1.18.2 jdolecek * 2. Redistributions in binary form must reproduce the above copyright
16 1.1.18.2 jdolecek * notice, this list of conditions and the following disclaimer in the
17 1.1.18.2 jdolecek * documentation and/or other materials provided with the distribution.
18 1.1.18.2 jdolecek *
19 1.1.18.2 jdolecek * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
20 1.1.18.2 jdolecek * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
21 1.1.18.2 jdolecek * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
22 1.1.18.2 jdolecek * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
23 1.1.18.2 jdolecek * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
24 1.1.18.2 jdolecek * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
25 1.1.18.2 jdolecek * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
26 1.1.18.2 jdolecek * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
27 1.1.18.2 jdolecek * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
28 1.1.18.2 jdolecek * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
29 1.1.18.2 jdolecek * POSSIBILITY OF SUCH DAMAGE.
30 1.1.18.2 jdolecek */
31 1.1.18.2 jdolecek
32 1.1.18.2 jdolecek #include <sys/param.h>
33 1.1.18.2 jdolecek #include <sys/types.h>
34 1.1.18.2 jdolecek #include <sys/bus.h>
35 1.1.18.2 jdolecek #include <sys/cdefs.h>
36 1.1.18.2 jdolecek #include <sys/device.h>
37 1.1.18.2 jdolecek #include <sys/errno.h>
38 1.1.18.2 jdolecek
39 1.1.18.2 jdolecek #include <arm/imx/imx23_rtcreg.h>
40 1.1.18.2 jdolecek #include <arm/imx/imx23_rtcvar.h>
41 1.1.18.2 jdolecek #include <arm/imx/imx23var.h>
42 1.1.18.2 jdolecek
43 1.1.18.2 jdolecek typedef struct rtc_softc {
44 1.1.18.2 jdolecek device_t sc_dev;
45 1.1.18.2 jdolecek bus_space_tag_t sc_iot;
46 1.1.18.2 jdolecek bus_space_handle_t sc_hdl;
47 1.1.18.2 jdolecek } *rtc_softc_t;
48 1.1.18.2 jdolecek
49 1.1.18.2 jdolecek static int rtc_match(device_t, cfdata_t, void *);
50 1.1.18.2 jdolecek static void rtc_attach(device_t, device_t, void *);
51 1.1.18.2 jdolecek static int rtc_activate(device_t, enum devact);
52 1.1.18.2 jdolecek
53 1.1.18.2 jdolecek static void rtc_init(struct rtc_softc *);
54 1.1.18.2 jdolecek static void rtc_reset(struct rtc_softc *);
55 1.1.18.2 jdolecek
56 1.1.18.2 jdolecek static rtc_softc_t _sc = NULL;
57 1.1.18.2 jdolecek
58 1.1.18.2 jdolecek CFATTACH_DECL3_NEW(rtc,
59 1.1.18.2 jdolecek sizeof(struct rtc_softc),
60 1.1.18.2 jdolecek rtc_match,
61 1.1.18.2 jdolecek rtc_attach,
62 1.1.18.2 jdolecek NULL,
63 1.1.18.2 jdolecek rtc_activate,
64 1.1.18.2 jdolecek NULL,
65 1.1.18.2 jdolecek NULL,
66 1.1.18.2 jdolecek 0
67 1.1.18.2 jdolecek );
68 1.1.18.2 jdolecek
69 1.1.18.2 jdolecek #define RTC_RD(sc, reg) \
70 1.1.18.2 jdolecek bus_space_read_4(sc->sc_iot, sc->sc_hdl, (reg))
71 1.1.18.2 jdolecek #define RTC_WR(sc, reg, val) \
72 1.1.18.2 jdolecek bus_space_write_4(sc->sc_iot, sc->sc_hdl, (reg), (val))
73 1.1.18.2 jdolecek
74 1.1.18.2 jdolecek #define RTC_SOFT_RST_LOOP 455 /* At least 1 us ... */
75 1.1.18.2 jdolecek
76 1.1.18.2 jdolecek static int
77 1.1.18.2 jdolecek rtc_match(device_t parent, cfdata_t match, void *aux)
78 1.1.18.2 jdolecek {
79 1.1.18.2 jdolecek struct apb_attach_args *aa = aux;
80 1.1.18.2 jdolecek
81 1.1.18.2 jdolecek if ((aa->aa_addr == HW_RTC_BASE) &&
82 1.1.18.2 jdolecek (aa->aa_size == HW_RTC_BASE_SIZE))
83 1.1.18.2 jdolecek return 1;
84 1.1.18.2 jdolecek
85 1.1.18.2 jdolecek return 0;
86 1.1.18.2 jdolecek }
87 1.1.18.2 jdolecek
88 1.1.18.2 jdolecek static void
89 1.1.18.2 jdolecek rtc_attach(device_t parent, device_t self, void *aux)
90 1.1.18.2 jdolecek {
91 1.1.18.2 jdolecek struct rtc_softc *sc = device_private(self);
92 1.1.18.2 jdolecek struct apb_attach_args *aa = aux;
93 1.1.18.2 jdolecek static int rtc_attached = 0;
94 1.1.18.2 jdolecek
95 1.1.18.2 jdolecek sc->sc_dev = self;
96 1.1.18.2 jdolecek sc->sc_iot = aa->aa_iot;
97 1.1.18.2 jdolecek
98 1.1.18.2 jdolecek if (rtc_attached) {
99 1.1.18.2 jdolecek aprint_error_dev(sc->sc_dev, "rtc is already attached\n");
100 1.1.18.2 jdolecek return;
101 1.1.18.2 jdolecek }
102 1.1.18.2 jdolecek
103 1.1.18.2 jdolecek if (bus_space_map(sc->sc_iot, aa->aa_addr, aa->aa_size, 0,
104 1.1.18.2 jdolecek &sc->sc_hdl))
105 1.1.18.2 jdolecek {
106 1.1.18.2 jdolecek aprint_error_dev(sc->sc_dev, "Unable to map bus space\n");
107 1.1.18.2 jdolecek return;
108 1.1.18.2 jdolecek }
109 1.1.18.2 jdolecek
110 1.1.18.2 jdolecek
111 1.1.18.2 jdolecek rtc_init(sc);
112 1.1.18.2 jdolecek rtc_reset(sc);
113 1.1.18.2 jdolecek
114 1.1.18.2 jdolecek aprint_normal("\n");
115 1.1.18.2 jdolecek
116 1.1.18.2 jdolecek rtc_attached = 1;
117 1.1.18.2 jdolecek
118 1.1.18.2 jdolecek return;
119 1.1.18.2 jdolecek }
120 1.1.18.2 jdolecek
121 1.1.18.2 jdolecek static int
122 1.1.18.2 jdolecek rtc_activate(device_t self, enum devact act)
123 1.1.18.2 jdolecek {
124 1.1.18.2 jdolecek
125 1.1.18.2 jdolecek return EOPNOTSUPP;
126 1.1.18.2 jdolecek }
127 1.1.18.2 jdolecek
128 1.1.18.2 jdolecek static void
129 1.1.18.2 jdolecek rtc_init(struct rtc_softc *sc)
130 1.1.18.2 jdolecek {
131 1.1.18.2 jdolecek _sc = sc;
132 1.1.18.2 jdolecek return;
133 1.1.18.2 jdolecek }
134 1.1.18.2 jdolecek
135 1.1.18.2 jdolecek /*
136 1.1.18.2 jdolecek * Remove pulldown resistors on the headphone outputs.
137 1.1.18.2 jdolecek */
138 1.1.18.2 jdolecek void
139 1.1.18.2 jdolecek rtc_release_gnd(int val)
140 1.1.18.2 jdolecek {
141 1.1.18.2 jdolecek struct rtc_softc *sc = _sc;
142 1.1.18.2 jdolecek
143 1.1.18.2 jdolecek if (sc == NULL) {
144 1.1.18.2 jdolecek aprint_error("rtc is not initalized");
145 1.1.18.2 jdolecek return;
146 1.1.18.2 jdolecek }
147 1.1.18.2 jdolecek if(val)
148 1.1.18.2 jdolecek RTC_WR(sc, HW_RTC_PERSISTENT0_SET, (1<<19));
149 1.1.18.2 jdolecek else
150 1.1.18.2 jdolecek RTC_WR(sc, HW_RTC_PERSISTENT0_CLR, (1<<19));
151 1.1.18.2 jdolecek
152 1.1.18.2 jdolecek return;
153 1.1.18.2 jdolecek }
154 1.1.18.2 jdolecek
155 1.1.18.2 jdolecek /*
156 1.1.18.2 jdolecek * Reset the RTC block.
157 1.1.18.2 jdolecek *
158 1.1.18.2 jdolecek * Inspired by i.MX23 RM "39.3.10 Correct Way to Soft Reset a Block"
159 1.1.18.2 jdolecek */
160 1.1.18.2 jdolecek static void
161 1.1.18.2 jdolecek rtc_reset(struct rtc_softc *sc)
162 1.1.18.2 jdolecek {
163 1.1.18.2 jdolecek unsigned int loop;
164 1.1.18.2 jdolecek
165 1.1.18.2 jdolecek /* Prepare for soft-reset by making sure that SFTRST is not currently
166 1.1.18.2 jdolecek * asserted. Also clear CLKGATE so we can wait for its assertion below.
167 1.1.18.2 jdolecek */
168 1.1.18.2 jdolecek RTC_WR(sc, HW_RTC_CTRL_CLR, HW_RTC_CTRL_SFTRST);
169 1.1.18.2 jdolecek
170 1.1.18.2 jdolecek /* Wait at least a microsecond for SFTRST to deassert. */
171 1.1.18.2 jdolecek loop = 0;
172 1.1.18.2 jdolecek while ((RTC_RD(sc, HW_RTC_CTRL) & HW_RTC_CTRL_SFTRST) ||
173 1.1.18.2 jdolecek (loop < RTC_SOFT_RST_LOOP))
174 1.1.18.2 jdolecek loop++;
175 1.1.18.2 jdolecek
176 1.1.18.2 jdolecek /* Clear CLKGATE so we can wait for its assertion below. */
177 1.1.18.2 jdolecek RTC_WR(sc, HW_RTC_CTRL_CLR, HW_RTC_CTRL_CLKGATE);
178 1.1.18.2 jdolecek
179 1.1.18.2 jdolecek /* Soft-reset the block. */
180 1.1.18.2 jdolecek RTC_WR(sc, HW_RTC_CTRL_SET, HW_RTC_CTRL_SFTRST);
181 1.1.18.2 jdolecek
182 1.1.18.2 jdolecek /* Wait until clock is in the gated state. */
183 1.1.18.2 jdolecek while (!(RTC_RD(sc, HW_RTC_CTRL) & HW_RTC_CTRL_CLKGATE));
184 1.1.18.2 jdolecek
185 1.1.18.2 jdolecek /* Bring block out of reset. */
186 1.1.18.2 jdolecek RTC_WR(sc, HW_RTC_CTRL_CLR, HW_RTC_CTRL_SFTRST);
187 1.1.18.2 jdolecek
188 1.1.18.2 jdolecek loop = 0;
189 1.1.18.2 jdolecek while ((RTC_RD(sc, HW_RTC_CTRL) & HW_RTC_CTRL_SFTRST) ||
190 1.1.18.2 jdolecek (loop < RTC_SOFT_RST_LOOP))
191 1.1.18.2 jdolecek loop++;
192 1.1.18.2 jdolecek
193 1.1.18.2 jdolecek RTC_WR(sc, HW_RTC_CTRL_CLR, HW_RTC_CTRL_CLKGATE);
194 1.1.18.2 jdolecek
195 1.1.18.2 jdolecek /* Wait until clock is in the NON-gated state. */
196 1.1.18.2 jdolecek while (RTC_RD(sc, HW_RTC_CTRL) & HW_RTC_CTRL_CLKGATE);
197 1.1.18.2 jdolecek
198 1.1.18.2 jdolecek return;
199 1.1.18.2 jdolecek }
200