xref: /netbsd-src/sys/arch/mvmeppc/isa/mkclock_isa.c (revision 267197ec1eebfcb9810ea27a89625b6ddf68e3e7)
1 /*	$NetBSD: mkclock_isa.c,v 1.10 2008/01/10 15:31:27 tsutsui Exp $	*/
2 
3 /*-
4  * Copyright (c) 2002 The NetBSD Foundation, Inc.
5  * All rights reserved.
6  *
7  * This code is derived from software contributed to The NetBSD Foundation
8  * by Klaus J. Klein.
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  * 3. All advertising materials mentioning features or use of this software
19  *    must display the following acknowledgement:
20  *	This product includes software developed by the NetBSD
21  *	Foundation, Inc. and its contributors.
22  * 4. Neither the name of The NetBSD Foundation nor the names of its
23  *    contributors may be used to endorse or promote products derived
24  *    from this software without specific prior written permission.
25  *
26  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
27  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
28  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
29  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
30  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
31  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
32  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
33  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
34  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
35  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
36  * POSSIBILITY OF SUCH DAMAGE.
37  */
38 
39 /*
40  * Mostek MK48T18 time-of-day chip attachment to ISA bus, using two
41  * 8-bit ports for address selection and one 8-bit port for data.
42  */
43 
44 #include <sys/cdefs.h>			/* RCS ID & Copyright macro defns */
45 __KERNEL_RCSID(0, "$NetBSD: mkclock_isa.c,v 1.10 2008/01/10 15:31:27 tsutsui Exp $");
46 
47 #include <sys/param.h>
48 #include <sys/kernel.h>
49 #include <sys/systm.h>
50 #include <sys/device.h>
51 
52 #include <machine/bus.h>
53 
54 #include <dev/clock_subr.h>
55 #include <dev/ic/mk48txxreg.h>
56 #include <dev/ic/mk48txxvar.h>
57 
58 #include <dev/isa/isavar.h>
59 
60 
61 /* Offsets of registers into ISA I/O space */
62 #define	MKCLOCK_STB0	0		/* Address low		*/
63 #define	MKCLOCK_STB1	1		/* Address high		*/
64 #define	MKCLOCK_DATA	3		/* Data port		*/
65 
66 #define	MKCLOCK_NPORTS	(MKCLOCK_DATA - MKCLOCK_STB0 + 1)
67 
68 
69 /* Autoconfiguration interface */
70 int	mkclock_isa_match(struct device *, struct cfdata *, void *);
71 void	mkclock_isa_attach(struct device *, struct device *, void *);
72 
73 CFATTACH_DECL(mkclock_isa, sizeof (struct mk48txx_softc),
74     mkclock_isa_match, mkclock_isa_attach, NULL, NULL);
75 
76 
77 /* mk48txx interface */
78 uint8_t	mkclock_isa_nvrd(struct mk48txx_softc *, int);
79 void	mkclock_isa_nvwr(struct mk48txx_softc *, int, uint8_t);
80 
81 
82 int
83 mkclock_isa_match(struct device *parent, struct cfdata *match, void *aux)
84 {
85 	struct isa_attach_args *ia = aux;
86 	struct mk48txx_softc mk48txx, *sc;
87 	uint8_t csr, ocsr;
88 	unsigned int t1, t2;
89 	int found;
90 
91 	found = 0;
92 
93 	if (ia->ia_nio < 1 ||
94 	    (ia->ia_io[0].ir_addr != ISA_UNKNOWN_PORT &&
95 	     ia->ia_io[0].ir_addr != 0x74))
96 		return (0);
97 
98         if (ia->ia_niomem > 0 &&
99 	    (ia->ia_iomem[0].ir_addr != ISA_UNKNOWN_IOMEM))
100 		return (0);
101 
102 	if (ia->ia_nirq > 0 &&
103 	    (ia->ia_irq[0].ir_irq != ISA_UNKNOWN_IRQ))
104 		return (0);
105 
106 	if (ia->ia_ndrq > 0 &&
107 	    (ia->ia_drq[0].ir_drq != ISA_UNKNOWN_DRQ))
108 		return (0);
109 
110 	/*
111 	 * Map I/O space, then try to determine if it's really there.
112 	 */
113 	sc = &mk48txx;
114 	sc->sc_bst = ia->ia_iot;
115 	if (bus_space_map(sc->sc_bst, 0x74, MKCLOCK_NPORTS, 0, &sc->sc_bsh))
116 		return (0);
117 
118 	/* Supposedly no control bits are set after POST; check for this. */
119 	ocsr = mkclock_isa_nvrd(sc, MK48T18_CLKOFF + MK48TXX_ICSR);
120 	if (ocsr != 0)
121 		goto unmap;
122 
123 	/* Set clock data to read mode, prohibiting updates from clock. */
124 	csr = ocsr | MK48TXX_CSR_READ;
125 	mkclock_isa_nvwr(sc, MK48T18_CLKOFF + MK48TXX_ICSR, csr);
126 	/* Compare. */
127 	if (mkclock_isa_nvrd(sc, MK48T18_CLKOFF + MK48TXX_ICSR) != csr)
128 		goto restore;
129 
130 	/* Read from the seconds counter. */
131 	t1 = FROMBCD(mkclock_isa_nvrd(sc, MK48T18_CLKOFF + MK48TXX_ISEC));
132 	if (t1 > 59)
133 		goto restore;
134 
135 	/* Make it tick again, wait, then look again. */
136 	mkclock_isa_nvwr(sc, MK48T18_CLKOFF + MK48TXX_ICSR, ocsr);
137 	DELAY(1100000);
138 	mkclock_isa_nvwr(sc, MK48T18_CLKOFF + MK48TXX_ICSR, csr);
139 	t2 = FROMBCD(mkclock_isa_nvrd(sc, MK48T18_CLKOFF + MK48TXX_ISEC));
140 	if (t2 > 59)
141 		goto restore;
142 
143 	/* If [1,2) seconds have passed since, call it a clock. */
144 	if ((t1 + 1) % 60 == t2 || (t1 + 2) % 60 == t2)
145 		found = 1;
146 
147  restore:
148 	mkclock_isa_nvwr(sc, MK48T18_CLKOFF + MK48TXX_ICSR, ocsr);
149  unmap:
150 	bus_space_unmap(sc->sc_bst, sc->sc_bsh, MKCLOCK_NPORTS);
151 
152 	if (found) {
153 		ia->ia_nio = 1;
154 		ia->ia_io[0].ir_addr = 0x74;
155 		ia->ia_io[0].ir_size = MKCLOCK_NPORTS;
156 
157 		ia->ia_niomem = 0;
158 		ia->ia_nirq = 0;
159 		ia->ia_ndrq = 0;
160 	}
161 
162 	return (found);
163 }
164 
165 void
166 mkclock_isa_attach(struct device *parent, struct device *self, void *aux)
167 {
168 	struct isa_attach_args *ia = aux;
169 	struct mk48txx_softc *sc = (void *)self;
170 
171 	/* Map I/O space. */
172 	sc->sc_bst = ia->ia_iot;
173 	if (bus_space_map(sc->sc_bst, ia->ia_io[0].ir_addr,
174 	    ia->ia_io[0].ir_size, 0, &sc->sc_bsh))
175 		panic("mkclock_isa_attach: couldn't map clock I/O space");
176 
177 	/* Attach to MI mk48txx driver. */
178 	sc->sc_model = "mk48t18";
179 	sc->sc_year0 = 1968;
180 	sc->sc_nvrd = mkclock_isa_nvrd;
181 	sc->sc_nvwr = mkclock_isa_nvwr;
182 
183 	mk48txx_attach(sc);
184 
185 	printf(" Timekeeper NVRAM/RTC\n");
186 }
187 
188 /*
189  * Bus access methods for MI mk48txx driver.
190  */
191 uint8_t
192 mkclock_isa_nvrd(struct mk48txx_softc *sc, int off)
193 {
194 	bus_space_tag_t iot;
195 	bus_space_handle_t ioh;
196 	uint8_t datum;
197 	int s;
198 
199 	iot = sc->sc_bst;
200 	ioh = sc->sc_bsh;
201 
202 	s = splclock();
203 	bus_space_write_1(iot, ioh, MKCLOCK_STB0, off & 0xff);
204 	bus_space_write_1(iot, ioh, MKCLOCK_STB1, off >> 8);
205 	datum = bus_space_read_1(iot, ioh, MKCLOCK_DATA);
206 	splx(s);
207 
208 	return (datum);
209 }
210 
211 void
212 mkclock_isa_nvwr(struct mk48txx_softc *sc, int off, uint8_t datum)
213 {
214 	bus_space_tag_t iot;
215 	bus_space_handle_t ioh;
216 	int s;
217 
218 	iot = sc->sc_bst;
219 	ioh = sc->sc_bsh;
220 
221 	s = splclock();
222 	bus_space_write_1(iot, ioh, MKCLOCK_STB0, off & 0xff);
223 	bus_space_write_1(iot, ioh, MKCLOCK_STB1, off >> 8);
224 	bus_space_write_1(iot, ioh, MKCLOCK_DATA, datum);
225 	splx(s);
226 }
227