xref: /netbsd-src/sys/arch/hp300/dev/rtc.c (revision 23e63c4b5cecc703250c97faac1ad970f4954821)
1 /*	$NetBSD: rtc.c,v 1.23 2023/12/20 00:40:43 thorpej Exp $	*/
2 
3 /*
4  * Copyright (c) 1988 University of Utah.
5  * Copyright (c) 1982, 1990, 1993
6  *	The Regents of the University of California.  All rights reserved.
7  *
8  * This code is derived from software contributed to Berkeley by
9  * the Systems Programming Group of the University of Utah Computer
10  * Science Department.
11  *
12  * Redistribution and use in source and binary forms, with or without
13  * modification, are permitted provided that the following conditions
14  * are met:
15  * 1. Redistributions of source code must retain the above copyright
16  *    notice, this list of conditions and the following disclaimer.
17  * 2. Redistributions in binary form must reproduce the above copyright
18  *    notice, this list of conditions and the following disclaimer in the
19  *    documentation and/or other materials provided with the distribution.
20  * 3. Neither the name of the University nor the names of its contributors
21  *    may be used to endorse or promote products derived from this software
22  *    without specific prior written permission.
23  *
24  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
25  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
26  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
27  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
28  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
29  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
30  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
31  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
32  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
33  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
34  * SUCH DAMAGE.
35  *
36  * from: Utah $Hdr: clock.c 1.18 91/01/21$
37  *
38  *	@(#)clock.c	8.2 (Berkeley) 1/12/94
39  */
40 
41 /*
42  * attachment for HP300 real-time clock (RTC)
43  */
44 
45 #include <sys/cdefs.h>
46 __KERNEL_RCSID(0, "$NetBSD: rtc.c,v 1.23 2023/12/20 00:40:43 thorpej Exp $");
47 
48 #include <sys/param.h>
49 #include <sys/systm.h>
50 #include <sys/device.h>
51 
52 #include <hp300/dev/intiovar.h>
53 #include <hp300/dev/rtcreg.h>
54 
55 #include <dev/clock_subr.h>
56 
57 struct rtc_softc {
58 	device_t sc_dev;
59 	bus_space_tag_t sc_bst;
60 	bus_space_handle_t sc_bsh;
61 	struct todr_chip_handle sc_handle;
62 };
63 
64 static int	rtcmatch(device_t, cfdata_t, void *);
65 static void	rtcattach(device_t, device_t, void *aux);
66 
67 CFATTACH_DECL_NEW(rtc, sizeof(struct rtc_softc),
68     rtcmatch, rtcattach, NULL, NULL);
69 
70 static int	rtc_gettime_ymdhms(todr_chip_handle_t, struct clock_ymdhms *);
71 static int	rtc_settime_ymdhms(todr_chip_handle_t, struct clock_ymdhms *);
72 static uint8_t	rtc_readreg(struct rtc_softc *, int);
73 static uint8_t	rtc_writereg(struct rtc_softc *, int, uint8_t);
74 
75 
76 static int
rtcmatch(device_t parent,cfdata_t cf,void * aux)77 rtcmatch(device_t parent, cfdata_t cf, void *aux)
78 {
79 	struct intio_attach_args *ia = aux;
80 
81 	/* 425e doesn't have the traditional RTC at intio */
82 	if (machineid == HP_425 && mmuid == MMUID_425_E)
83 		return 0;
84 
85 	if (strcmp("rtc", ia->ia_modname) != 0)
86 		return 0;
87 
88 	return 1;
89 }
90 
91 static void
rtcattach(device_t parent,device_t self,void * aux)92 rtcattach(device_t parent, device_t self, void *aux)
93 {
94 	struct rtc_softc *sc = device_private(self);
95 	struct intio_attach_args *ia = aux;
96 	struct todr_chip_handle *todr_handle;
97 	bus_space_tag_t bst = ia->ia_bst;
98 
99 	sc->sc_dev = self;
100 	if (bus_space_map(bst, ia->ia_iobase, INTIO_DEVSIZE, 0,
101 	    &sc->sc_bsh)) {
102 		aprint_error(": can't map registers\n");
103 		return;
104 	}
105 
106 	aprint_normal("\n");
107 
108 	sc->sc_bst = bst;
109 
110 	todr_handle = &sc->sc_handle;
111 	todr_handle->cookie = sc;
112 	todr_handle->todr_gettime = NULL;
113 	todr_handle->todr_settime = NULL;
114 	todr_handle->todr_gettime_ymdhms = rtc_gettime_ymdhms;
115 	todr_handle->todr_settime_ymdhms = rtc_settime_ymdhms;
116 	todr_handle->todr_setwen = NULL;
117 
118 	todr_attach(todr_handle);
119 }
120 
121 static int
rtc_gettime_ymdhms(todr_chip_handle_t handle,struct clock_ymdhms * dt)122 rtc_gettime_ymdhms(todr_chip_handle_t handle, struct clock_ymdhms *dt)
123 {
124 	struct rtc_softc *sc;
125 	int i, year;
126 	bool read_okay;
127 	uint8_t rtc_registers[NUM_RTC_REGS];
128 
129 	sc = handle->cookie;
130 
131 	/* read rtc registers */
132 	read_okay = false;
133 	while (!read_okay) {
134 		read_okay = true;
135 		for (i = 0; i < NUM_RTC_REGS; i++)
136 			rtc_registers[i] = rtc_readreg(sc, i);
137 		for (i = 0; i < NUM_RTC_REGS; i++)
138 			if (rtc_registers[i] != rtc_readreg(sc, i))
139 				read_okay = false;
140 	}
141 
142 #define	rtc_to_decimal(a,b)	(rtc_registers[a] * 10 + rtc_registers[b])
143 
144 	dt->dt_sec  = rtc_to_decimal(1, 0);
145 	dt->dt_min  = rtc_to_decimal(3, 2);
146 	dt->dt_hour = (rtc_registers[5] & RTC_REG5_HOUR) * 10 +
147 	    rtc_registers[4];
148 	dt->dt_day  = rtc_to_decimal(8, 7);
149 	dt->dt_mon  = rtc_to_decimal(10, 9);
150 
151 	year = rtc_to_decimal(12, 11) + RTC_BASE_YEAR;
152 	if (year < POSIX_BASE_YEAR)
153 		year += 100;
154 	dt->dt_year = year;
155 
156 #undef	rtc_to_decimal
157 
158 	return 0;
159 }
160 
161 static int
rtc_settime_ymdhms(todr_chip_handle_t handle,struct clock_ymdhms * dt)162 rtc_settime_ymdhms(todr_chip_handle_t handle, struct clock_ymdhms *dt)
163 {
164 	struct rtc_softc *sc;
165 	int i, year;
166 	uint8_t rtc_registers[NUM_RTC_REGS];
167 
168 	sc = handle->cookie;
169 	year = dt->dt_year - RTC_BASE_YEAR;
170 	if (year > 99)
171 		year -= 100;
172 
173 #define	decimal_to_rtc(a,b,n)		\
174 	rtc_registers[a] = (n) % 10;	\
175 	rtc_registers[b] = (n) / 10;
176 
177 	decimal_to_rtc(0, 1, dt->dt_sec);
178 	decimal_to_rtc(2, 3, dt->dt_min);
179 	decimal_to_rtc(7, 8, dt->dt_day);
180 	decimal_to_rtc(9, 10, dt->dt_mon);
181 	decimal_to_rtc(11, 12, year);
182 
183 	rtc_registers[4] = dt->dt_hour % 10;
184 	rtc_registers[5] = ((dt->dt_hour / 10) & RTC_REG5_HOUR) | RTC_REG5_24HR;
185 
186 	rtc_registers[6] = 0;
187 
188 #undef	decimal_to_rtc
189 
190 	/* write rtc registers */
191 	rtc_writereg(sc, 15, 13);	/* reset prescalar */
192 	for (i = 0; i < NUM_RTC_REGS; i++)
193 		if (rtc_registers[i] !=
194 		    rtc_writereg(sc, i, rtc_registers[i]))
195 			return 1;
196 	return 0;
197 }
198 
199 static uint8_t
rtc_readreg(struct rtc_softc * sc,int reg)200 rtc_readreg(struct rtc_softc *sc, int reg)
201 {
202 	bus_space_tag_t bst = sc->sc_bst;
203 	bus_space_handle_t bsh = sc->sc_bsh;
204 	uint8_t data;
205 	int s = splvm();
206 
207 	data = reg;
208 	intio_device_writecmd(bst, bsh, RTC_SET_REG, &data, 1);
209 	intio_device_readcmd(bst, bsh, RTC_READ_REG, &data);
210 
211 	splx(s);
212 	return data;
213 }
214 
215 static uint8_t
rtc_writereg(struct rtc_softc * sc,int reg,uint8_t data)216 rtc_writereg(struct rtc_softc *sc, int reg, uint8_t data)
217 {
218 	bus_space_tag_t bst = sc->sc_bst;
219 	bus_space_handle_t bsh = sc->sc_bsh;
220 	uint8_t tmp;
221 	int s = splvm();
222 
223 	tmp = (data << 4) | reg;
224 	intio_device_writecmd(bst, bsh, RTC_SET_REG, &tmp, 1);
225 	intio_device_writecmd(bst, bsh, RTC_WRITE_REG, NULL, 0);
226 	intio_device_readcmd(bst, bsh, RTC_READ_REG, &tmp);
227 
228 	splx(s);
229 	return tmp;
230 }
231