1 /* $NetBSD: clock.c,v 1.18 2024/01/19 18:18:55 thorpej Exp $ */
2
3 /*
4 * Copyright (c) 1982, 1990, 1993
5 * The Regents of the University of California. All rights reserved.
6 *
7 * This code is derived from software contributed to Berkeley by
8 * the Systems Programming Group of the University of Utah Computer
9 * Science Department.
10 *
11 * Redistribution and use in source and binary forms, with or without
12 * modification, are permitted provided that the following conditions
13 * are met:
14 * 1. Redistributions of source code must retain the above copyright
15 * notice, this list of conditions and the following disclaimer.
16 * 2. Redistributions in binary form must reproduce the above copyright
17 * notice, this list of conditions and the following disclaimer in the
18 * documentation and/or other materials provided with the distribution.
19 * 3. Neither the name of the University nor the names of its contributors
20 * may be used to endorse or promote products derived from this software
21 * without specific prior written permission.
22 *
23 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
24 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
25 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
26 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
27 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
28 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
29 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
30 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
31 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
32 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
33 * SUCH DAMAGE.
34 *
35 * from: Utah Hdr: clock.c 1.18 91/01/21$
36 * from: @(#)clock.c 8.2 (Berkeley) 1/12/94
37 */
38
39 /*
40 * Copyright (c) 2001 Matthew Fredette
41 * Copyright (c) 1994 Gordon W. Ross
42 * Copyright (c) 1993 Adam Glass
43 * Copyright (c) 1988 University of Utah.
44 *
45 * This code is derived from software contributed to Berkeley by
46 * the Systems Programming Group of the University of Utah Computer
47 * Science Department.
48 *
49 * Redistribution and use in source and binary forms, with or without
50 * modification, are permitted provided that the following conditions
51 * are met:
52 * 1. Redistributions of source code must retain the above copyright
53 * notice, this list of conditions and the following disclaimer.
54 * 2. Redistributions in binary form must reproduce the above copyright
55 * notice, this list of conditions and the following disclaimer in the
56 * documentation and/or other materials provided with the distribution.
57 * 3. All advertising materials mentioning features or use of this software
58 * must display the following acknowledgement:
59 * This product includes software developed by the University of
60 * California, Berkeley and its contributors.
61 * 4. Neither the name of the University nor the names of its contributors
62 * may be used to endorse or promote products derived from this software
63 * without specific prior written permission.
64 *
65 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
66 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
67 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
68 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
69 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
70 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
71 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
72 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
73 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
74 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
75 * SUCH DAMAGE.
76 *
77 * from: Utah Hdr: clock.c 1.18 91/01/21$
78 * from: @(#)clock.c 8.2 (Berkeley) 1/12/94
79 */
80
81 /*
82 * Machine-dependent clock routines for the Am9513
83 * Written by Matthew Fredette, based on the sun3 clock.c by
84 * Adam Glass and Gordon Ross.
85 */
86
87 #include <sys/cdefs.h>
88 __KERNEL_RCSID(0, "$NetBSD: clock.c,v 1.18 2024/01/19 18:18:55 thorpej Exp $");
89
90 #include <sys/param.h>
91 #include <sys/systm.h>
92 #include <sys/time.h>
93 #include <sys/kernel.h>
94 #include <sys/device.h>
95
96 #include <machine/autoconf.h>
97 #include <machine/cpu.h>
98 #include <machine/frame.h>
99 #include <machine/leds.h>
100 #include <machine/vectors.h>
101
102 #include <sun2/sun2/control.h>
103 #include <sun2/sun2/enable.h>
104 #include <sun2/sun2/machdep.h>
105
106 #include <dev/clock_subr.h>
107 #include <dev/ic/am9513reg.h>
108
109 /*
110 * Carefully define the basic CPU clock rate so
111 * that time-of-day calculations don't float
112 *
113 * Note that the CLK_BASIC is divided by 4 before we can count with it,
114 * e.g. F1 ticks CLK_BASIC/4 times a second.
115 */
116 #define SUN2_CLK_BASIC (19660800)
117 #define SUN2_CLK_TICKS(func, hz) \
118 (((SUN2_CLK_BASIC / 4) / AM9513_CM_SOURCE_Fn_DIV(func)) / (hz))
119
120 /* These define which counters are used for what. */
121 #define SUN2_CLK_NMI AM9513_TIMER1 /* Non Maskable Interrupts */
122 #define SUN2_CLK_TIMER AM9513_TIMER2 /* Timer 2 */
123 #define SUN2_CLK_UNUSED AM9513_TIMER3 /* Unused timer */
124 #define SUN2_CLK_FAST_LO AM9513_TIMER4 /* Timer 4 for realtime, low order */
125 #define SUN2_CLK_FAST_HI AM9513_TIMER5 /* Timer 5 for realtime, high order */
126
127 #define CLOCK_PRI 5
128 #define IREG_CLK_BITS (IREG_CLOCK_ENAB_7 | IREG_CLOCK_ENAB_5)
129
130 void _isr_clock(void); /* in locore.s */
131 void clock_intr(struct clockframe);
132
133 static bus_space_tag_t am9513_bt;
134 static bus_space_handle_t am9513_bh;
135 #define am9513_write_clk_cmd(val) \
136 bus_space_write_2(am9513_bt, am9513_bh, AM9513_CLK_CMD, val)
137 #define am9513_write_clk_data(val) \
138 bus_space_write_2(am9513_bt, am9513_bh, AM9513_CLK_DATA, val)
139
140 static int clock_match(device_t, cfdata_t, void *args);
141 static void clock_attach(device_t, device_t, void *);
142
143 CFATTACH_DECL_NEW(clock, 0,
144 clock_match, clock_attach, NULL, NULL);
145
146 static int clock_attached;
147
148 static int
clock_match(device_t parent,cfdata_t cf,void * args)149 clock_match(device_t parent, cfdata_t cf, void *args)
150 {
151 struct obio_attach_args *oba = args;
152 bus_space_handle_t bh;
153 bool matched;
154
155 /* This driver only supports one unit. */
156 if (clock_attached)
157 return 0;
158
159 /* Make sure there is something there... */
160 if (bus_space_map(oba->oba_bustag, oba->oba_paddr,
161 sizeof(struct am9513), 0, &bh))
162 return 0;
163 matched = (bus_space_peek_2(oba->oba_bustag, bh, 0, NULL) == 0);
164 bus_space_unmap(oba->oba_bustag, bh, sizeof(struct am9513));
165 if (!matched)
166 return 0;
167
168 /* Default interrupt priority. */
169 if (oba->oba_pri == -1)
170 oba->oba_pri = CLOCK_PRI;
171
172 return 1;
173 }
174
175 static void
clock_attach(device_t parent,device_t self,void * args)176 clock_attach(device_t parent, device_t self, void *args)
177 {
178 struct obio_attach_args *oba = args;
179 bus_space_handle_t bh;
180
181 clock_attached = 1;
182
183 aprint_normal("\n");
184
185 /* Get a mapping for it. */
186 if (bus_space_map(oba->oba_bustag, oba->oba_paddr,
187 sizeof(struct am9513), 0, &bh))
188 panic("%s: can't map clock", __func__);
189 am9513_bt = oba->oba_bustag;
190 am9513_bh = bh;
191
192 /*
193 * Set the clock to the correct interrupt rate, but
194 * do not enable the interrupt until cpu_initclocks.
195 */
196
197 /* Disarm the timer and NMI. */
198 am9513_write_clk_cmd(AM9513_CMD_DISARM(SUN2_CLK_TIMER | SUN2_CLK_NMI));
199 am9513_write_clk_cmd(AM9513_CMD_CLEAR_OUTPUT(SUN2_CLK_TIMER));
200 am9513_write_clk_cmd(AM9513_CMD_CLEAR_OUTPUT(SUN2_CLK_NMI));
201
202 /* Set the clock to 100 Hz, but do not enable it yet. */
203 am9513_write_clk_cmd(AM9513_CMD_LOAD_MODE(SUN2_CLK_TIMER));
204 am9513_write_clk_data((AM9513_CM_MODE_D | AM9513_CM_SOURCE_F2 |
205 AM9513_CM_OUTPUT_TC_TOGGLED));
206 am9513_write_clk_cmd(AM9513_CMD_LOAD_LOAD(SUN2_CLK_TIMER));
207 am9513_write_clk_data(SUN2_CLK_TICKS(AM9513_CM_SOURCE_F2, 100));
208
209 /*
210 * Can not hook up the ISR until cpu_initclocks()
211 * because hardclock is not ready until then.
212 * For now, the handler is _isr_autovec(), which
213 * will complain if it gets clock interrupts.
214 */
215 }
216
217 /*
218 * Set or clear the desired clock bits in the interrupt
219 * register. We have to be extremely careful that we do it
220 * in such a manner that we don't get ourselves lost.
221 * XXX: Watch out! It's really easy to break this!
222 */
223 void
set_clk_mode(int prom_clock,int on)224 set_clk_mode(int prom_clock, int on)
225 {
226 int timer;
227
228 #ifdef DIAGNOSTIC
229 /* Assertion: were are at splhigh! */
230 if ((getsr() & PSL_IPL) < PSL_IPL7)
231 panic("%s: bad ipl", __func__);
232 #endif
233
234 /* Get the timer we're talking about. */
235 timer = (prom_clock ? SUN2_CLK_NMI : SUN2_CLK_TIMER);
236
237 /* First, turn off the "master" enable bit. */
238 enable_reg_and(~ENA_INTS);
239
240 /*
241 * Arm the timer we're supposed to turn on.
242 */
243 if (on) {
244 am9513_write_clk_cmd(AM9513_CMD_ARM(timer));
245 }
246
247 /*
248 * Disarm and clear the timers we're supposed to turn off.
249 */
250 else {
251 am9513_write_clk_cmd(AM9513_CMD_DISARM(timer));
252 am9513_write_clk_cmd(AM9513_CMD_CLEAR_OUTPUT(timer));
253 }
254
255 /* Finally, turn the "master" enable back on. */
256 enable_reg_or(ENA_INTS);
257 }
258
259 /*
260 * Set up the real-time clock (enable clock interrupts).
261 * Leave stathz 0 since there is no secondary clock available.
262 * Note that clock interrupts MUST STAY DISABLED until here.
263 */
264 void
cpu_initclocks(void)265 cpu_initclocks(void)
266 {
267 int s;
268
269 s = splhigh();
270
271 /* Install isr (in locore.s) that calls clock_intr(). */
272 vec_set_entry(VECI_INTRAV0 + 5, _isr_clock);
273
274 /* Now enable the clock at level 5 in the interrupt reg. */
275 set_clk_mode(0, 1);
276
277 splx(s);
278 }
279
280 /*
281 * This doesn't need to do anything, as we have only one timer and
282 * profhz==stathz==hz.
283 */
284 void
setstatclockrate(int newhz)285 setstatclockrate(int newhz)
286 {
287
288 /* nothing */
289 }
290
291 /*
292 * This is called by the "custom" interrupt handler.
293 * Note that we can get ZS interrupts while this runs,
294 * and zshard may touch the interrupt_reg, so we must
295 * be careful to use the single_inst_* macros to modify
296 * the interrupt register atomically.
297 */
298 void
clock_intr(struct clockframe cf)299 clock_intr(struct clockframe cf)
300 {
301
302 intr_depth++;
303
304 /* Read the clock interrupt register. */
305 am9513_write_clk_cmd(AM9513_CMD_CLEAR_OUTPUT(SUN2_CLK_TIMER));
306
307 { /* Entertainment! */
308 #ifdef LED_IDLE_CHECK
309 /* With this option, LEDs move only when CPU is idle. */
310 extern char _Idle[]; /* locore.s */
311 if (cf.cf_pc == (long)_Idle)
312 #endif
313 leds_intr();
314 }
315
316 /* Call common clock interrupt handler. */
317 hardclock(&cf);
318
319 intr_depth--;
320
321 ATOMIC_CAS_CHECK(&cf);
322 }
323