1 /*        $NetBSD: oclock.c,v 1.21 2021/01/24 07:36:54 mrg 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 Paul Kranenburg.
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  * sun4 intersil time-of-day clock driver. This chip also provides
34  * the system timer.
35  *
36  * Only 4/100's and 4/200's have this old clock device.
37  */
38 
39 #include <sys/cdefs.h>
40 __KERNEL_RCSID(0, "$NetBSD: oclock.c,v 1.21 2021/01/24 07:36:54 mrg Exp $");
41 
42 #include "opt_sparc_arch.h"
43 
44 #include <sys/param.h>
45 #include <sys/kernel.h>
46 #include <sys/device.h>
47 #include <sys/systm.h>
48 #include <sys/bus.h>
49 
50 #include <machine/promlib.h>
51 #include <machine/autoconf.h>
52 
53 #include <sparc/sparc/timervar.h>
54 
55 #include <dev/clock_subr.h>
56 #include <dev/ic/intersil7170reg.h>
57 #include <dev/ic/intersil7170var.h>
58 
59 static int oclockmatch(device_t, cfdata_t, void *);
60 static void oclockattach(device_t, device_t, void *);
61 
62 CFATTACH_DECL_NEW(oclock, sizeof(struct intersil7170_softc),
63     oclockmatch, oclockattach, NULL, NULL);
64 
65 #if defined(SUN4)
66 static bus_space_tag_t i7_bt;
67 static bus_space_handle_t i7_bh;
68 
69 #define intersil_disable()                                                      \
70           bus_space_write_1(i7_bt, i7_bh, INTERSIL_ICMD,                        \
71               INTERSIL_COMMAND(INTERSIL_CMD_RUN, INTERSIL_CMD_IDISABLE));
72 
73 #define intersil_enable()                                                       \
74           bus_space_write_1(i7_bt, i7_bh, INTERSIL_ICMD,                        \
75               INTERSIL_COMMAND(INTERSIL_CMD_RUN, INTERSIL_CMD_IENABLE));
76 
77 #define intersil_clear() bus_space_read_1(i7_bt, i7_bh, INTERSIL_IINTR)
78 
79 int oclockintr(void *);
80 static struct intrhand level10 = { oclockintr };
81 void oclock_init(void);
82 #endif /* SUN4 */
83 
84 /*
85  * old clock match routine
86  */
87 static int
oclockmatch(device_t parent,cfdata_t cf,void * aux)88 oclockmatch(device_t parent, cfdata_t cf, void *aux)
89 {
90           union obio_attach_args *uoba = aux;
91           struct obio4_attach_args *oba;
92 
93           if (uoba->uoba_isobio4 == 0)
94                     return (0);
95 
96           /* Only these sun4s have oclock */
97           if (!CPU_ISSUN4 ||
98               (cpuinfo.cpu_type != CPUTYP_4_100 &&
99                cpuinfo.cpu_type != CPUTYP_4_200))
100                     return (0);
101 
102           /* Make sure there is something there */
103           oba = &uoba->uoba_oba4;
104           return (bus_space_probe(oba->oba_bustag, oba->oba_paddr,
105                                         1,        /* probe size */
106                                         0,        /* offset */
107                                         0,        /* flags */
108                                         NULL, NULL));
109 }
110 
111 /* ARGSUSED */
112 static void
oclockattach(device_t parent,device_t self,void * aux)113 oclockattach(device_t parent, device_t self, void *aux)
114 {
115 #if defined(SUN4)
116           struct intersil7170_softc *sc = device_private(self);
117           union obio_attach_args *uoba = aux;
118           struct obio4_attach_args *oba = &uoba->uoba_oba4;
119 
120           oldclk = 1;  /* we've got an oldie! */
121 
122           sc->sc_dev = self;
123           sc->sc_bst = oba->oba_bustag;
124           if (bus_space_map(sc->sc_bst,
125                                 oba->oba_paddr,
126                                 sizeof(struct intersil7170),
127                                 BUS_SPACE_MAP_LINEAR,       /* flags */
128                                 &sc->sc_bsh) != 0) {
129                     aprint_error(": can't map register\n");
130                     return;
131           }
132           i7_bt = sc->sc_bst;
133           i7_bh = sc->sc_bsh;
134 
135           /*
136            * calibrate delay()
137            */
138           ienab_bic(IE_L14 | IE_L10);   /* disable all clock intrs */
139           for (timerblurb = 1; ; timerblurb++) {
140                     int ival;
141 
142                     /* Set to 1/100 second interval */
143                     bus_space_write_1(sc->sc_bst, sc->sc_bsh, INTERSIL_IINTR,
144                         INTERSIL_INTER_CSECONDS);
145 
146                     /* enable clock */
147                     intersil_enable();
148 
149                     while ((intersil_clear() & INTERSIL_INTER_PENDING) == 0)
150                               /* sync with interrupt */;
151                     while ((intersil_clear() & INTERSIL_INTER_PENDING) == 0)
152                               /* XXX: do it again, seems to need it */;
153 
154                     /* Probe 1/100 sec delay */
155                     delay(10000);
156 
157                     /* clear, save value */
158                     ival = intersil_clear();
159 
160                     /* disable clock */
161                     intersil_disable();
162 
163                     if ((ival & INTERSIL_INTER_PENDING) != 0) {
164                               aprint_normal(" delay constant %d%s\n", timerblurb,
165                                         (timerblurb == 1) ? " [TOO SMALL?]" : "");
166                               break;
167                     }
168                     if (timerblurb > 10) {
169                               aprint_normal("\n");
170                               aprint_error_dev(self, "calibration failing; "
171                                   "clamped at %d\n", timerblurb);
172                               break;
173                     }
174           }
175 
176           timer_init = oclock_init;
177 
178           /* link interrupt handler */
179           intr_establish(10, 0, &level10, NULL, false);
180 
181           /* Our TOD clock year 0 represents 1968 */
182           sc->sc_year0 = 1968;
183           intersil7170_attach(sc);
184 
185           aprint_normal("\n");
186 #endif /* SUN4 */
187 }
188 
189 #if defined(SUN4)
190 /*
191  * Set up the real-time and statistics clocks.
192  * Leave stathz 0 only if no alternative timer is available.
193  *
194  * The frequencies of these clocks must be an even number of microseconds.
195  */
196 void
oclock_init(void)197 oclock_init(void)
198 {
199 
200           profhz = hz = 100;
201           tick = 1000000 / hz;
202 
203           /* Select 1/100 second interval */
204           bus_space_write_1(i7_bt, i7_bh, INTERSIL_IINTR,
205                                 INTERSIL_INTER_CSECONDS);
206 
207           ienab_bic(IE_L14 | IE_L10);   /* disable all clock intrs */
208           intersil_disable();           /* disable clock */
209           (void)intersil_clear();                 /* clear interrupts */
210           ienab_bis(IE_L10);            /* enable l10 interrupt */
211           intersil_enable();            /* enable clock */
212 }
213 
214 /*
215  * Level 10 (clock) interrupts from system counter.
216  * If we are using the FORTH PROM for console input, we need to check
217  * for that here as well, and generate a software interrupt to read it.
218  */
219 int
oclockintr(void * cap)220 oclockintr(void *cap)
221 {
222           int s;
223 
224           /*
225            * Protect the clearing of the clock interrupt.  If we don't
226            * do this, and we're interrupted (by the zs, for example),
227            * the clock stops!
228            * XXX WHY DOES THIS HAPPEN?
229            */
230           s = splhigh();
231 
232           (void)intersil_clear();
233           ienab_bic(IE_L10);  /* clear interrupt */
234           ienab_bis(IE_L10);  /* enable interrupt */
235           splx(s);
236 
237           hardclock((struct clockframe *)cap);
238           return (1);
239 }
240 #endif /* SUN4 */
241