1 /* $NetBSD: mcclock_ofisa.c,v 1.1 2021/04/27 21:39:39 thorpej Exp $ */
2
3 /*-
4 * Copyright (c) 2021 The NetBSD Foundation, Inc.
5 * All rights reserved.
6 *
7 * This code is derived from software contributed to The NetBSD Foundation
8 * by Jason R. Thorpe.
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 /*
33 * OFW ISA attachment for the mc146818 real time clock.
34 */
35
36 #include <sys/cdefs.h>
37 __KERNEL_RCSID(0, "$NetBSD: mcclock_ofisa.c,v 1.1 2021/04/27 21:39:39 thorpej Exp $");
38
39 #include <sys/param.h>
40 #include <sys/systm.h>
41 #include <sys/kernel.h>
42 #include <sys/device.h>
43
44 #include <sys/bus.h>
45
46 #include <dev/clock_subr.h>
47 #include <dev/ic/mc146818var.h>
48
49 #include <dev/ofw/openfirm.h>
50 #include <dev/isa/isavar.h>
51 #include <dev/ofisa/ofisavar.h>
52
53 struct mcclock_ofisa_platform_data {
54 int year0;
55 int flags;
56 };
57
58 static const struct device_compatible_entry compat_data[] = {
59 { .compat = "pnpPNP,b00" },
60 DEVICE_COMPAT_EOL
61 };
62
63 static const struct mcclock_ofisa_platform_data dec_dnard_data = {
64 .year0 = 1900,
65 .flags = MC146818_BCD,
66 };
67
68 static const struct device_compatible_entry platform_data[] = {
69 { .compat = "DEC,DNARD", .data = &dec_dnard_data, },
70 DEVICE_COMPAT_EOL
71 };
72
73 static const struct mcclock_ofisa_platform_data *
lookup_platform_data(char * model,size_t const size)74 lookup_platform_data(char *model, size_t const size)
75 {
76 const struct device_compatible_entry *dce;
77
78 if (OF_getprop(OF_finddevice("/"), "model", model, size) <= 0) {
79 return NULL;
80 }
81
82 /* should be plenty big enough, but never hurts... */
83 model[size - 1] = '\0';
84 const char *cmodel = model;
85
86 dce = device_compatible_lookup(&cmodel, 1, platform_data);
87 if (dce != NULL) {
88 return dce->data;
89 }
90 return NULL;
91 }
92
93 static u_int
mcclock_ofisa_read(struct mc146818_softc * sc,u_int reg)94 mcclock_ofisa_read(struct mc146818_softc *sc, u_int reg)
95 {
96 bus_space_write_1(sc->sc_bst, sc->sc_bsh, 0, reg);
97 return bus_space_read_1(sc->sc_bst, sc->sc_bsh, 1);
98 }
99
100 static void
mcclock_ofisa_write(struct mc146818_softc * sc,u_int reg,u_int datum)101 mcclock_ofisa_write(struct mc146818_softc *sc, u_int reg, u_int datum)
102 {
103 bus_space_write_1(sc->sc_bst, sc->sc_bsh, 0, reg);
104 bus_space_write_1(sc->sc_bst, sc->sc_bsh, 1, (uint8_t)datum);
105 }
106
107 static int
mcclock_ofisa_match(device_t parent,cfdata_t cf,void * aux)108 mcclock_ofisa_match(device_t parent, cfdata_t cf, void *aux)
109 {
110 struct ofisa_attach_args *aa = aux;
111 int rv;
112
113 rv = of_compatible_match(aa->oba.oba_phandle, compat_data) ? 5 : 0;
114 #ifdef _MCCLOCK_OFISA_MD_MATCH
115 if (!rv)
116 rv = mcclock_ofisa_md_match(parent, cf, aux);
117 #endif
118 return rv;
119 }
120
121 static void
mcclock_ofisa_attach(device_t parent,device_t self,void * aux)122 mcclock_ofisa_attach(device_t parent, device_t self, void *aux)
123 {
124 struct mc146818_softc *sc = device_private(self);
125 struct ofisa_attach_args *aa = aux;
126 const struct mcclock_ofisa_platform_data *pd;
127 struct ofisa_reg_desc reg;
128 char model[64];
129 int n;
130
131 sc->sc_dev = self;
132
133 n = ofisa_reg_get(aa->oba.oba_phandle, ®, 1);
134 #ifdef _MCCLOCK_OFISA_MD_REG_FIXUP
135 n = mcclock_ofisa_md_reg_fixup(parent, self, aux, ®, 1, n);
136 #endif
137 if (n != 1) {
138 aprint_error(": error getting register data\n");
139 return;
140 }
141 if (reg.len != 2) {
142 aprint_error(": weird register size (%lu, expected 2)\n",
143 (unsigned long)reg.len);
144 return;
145 }
146
147 /*
148 * We don't configure interrupts here; we're only using this
149 * for the TODR.
150 */
151
152 pd = lookup_platform_data(model, sizeof(model));
153
154 sc->sc_bst = (reg.type == OFISA_REG_TYPE_IO) ? aa->iot : aa->memt;
155 if (bus_space_map(sc->sc_bst, reg.addr, reg.len, 0, &sc->sc_bsh) != 0) {
156 aprint_error(": can't map register space\n");
157 return;
158 }
159
160 /*
161 * These default to 0. We'll warn after attaching if we didn't
162 * find any platform data.
163 */
164 if (pd != NULL) {
165 sc->sc_year0 = pd->year0;
166 sc->sc_flag = pd->flags;
167 }
168 sc->sc_mcread = mcclock_ofisa_read;
169 sc->sc_mcwrite = mcclock_ofisa_write;
170
171 mc146818_attach(sc);
172
173 aprint_normal("\n");
174
175 if (pd == NULL) {
176 /*
177 * We could dynamically compute at least BCD-ness and
178 * base year by comparing against the OFW get-time
179 * call, but it hardly seems worth it right now.
180 */
181 aprint_error_dev(self,
182 "WARNING: no platform data for '%s', using defaults.\n",
183 model);
184 }
185 }
186
187 CFATTACH_DECL_NEW(mcclock_ofisa, sizeof(struct mc146818_softc),
188 mcclock_ofisa_match, mcclock_ofisa_attach, NULL, NULL);
189