xref: /titanic_41/usr/src/uts/sun4u/io/todmostek.c (revision 6d24d8e5e4f6a2d14992d9392981d8a16d695aec)
1 /*
2  * CDDL HEADER START
3  *
4  * The contents of this file are subject to the terms of the
5  * Common Development and Distribution License (the "License").
6  * You may not use this file except in compliance with the License.
7  *
8  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
9  * or http://www.opensolaris.org/os/licensing.
10  * See the License for the specific language governing permissions
11  * and limitations under the License.
12  *
13  * When distributing Covered Code, include this CDDL HEADER in each
14  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
15  * If applicable, add the following below this CDDL HEADER, with the
16  * fields enclosed by brackets "[]" replaced with your own identifying
17  * information: Portions Copyright [yyyy] [name of copyright owner]
18  *
19  * CDDL HEADER END
20  */
21 /*
22  * Copyright 2009 Sun Microsystems, Inc.  All rights reserved.
23  * Use is subject to license terms.
24  */
25 
26 /*
27  * tod driver module for Mostek M48T59 part
28  */
29 
30 #include <sys/types.h>
31 #include <sys/param.h>
32 #include <sys/sysmacros.h>
33 #include <sys/systm.h>
34 #include <sys/errno.h>
35 #include <sys/modctl.h>
36 #include <sys/autoconf.h>
37 #include <sys/debug.h>
38 #include <sys/clock.h>
39 #include <sys/todmostek.h>
40 #include <sys/reboot.h>
41 #include <sys/cmn_err.h>
42 #include <sys/cpuvar.h>
43 
44 static timestruc_t	todm_get(void);
45 static void		todm_set(timestruc_t);
46 static uint_t		todm_set_watchdog_timer(uint_t);
47 static uint_t		todm_clear_watchdog_timer(void);
48 static void		todm_set_power_alarm(timestruc_t);
49 static void		todm_clear_power_alarm(void);
50 static uint64_t		todm_get_cpufrequency(void);
51 
52 static uchar_t watchdog_bits = 0;
53 static uint_t watchdog_timeout;
54 
55 extern uint64_t find_cpufrequency(volatile uchar_t *);
56 
57 /*
58  * Module linkage information for the kernel.
59  */
60 static struct modlmisc modlmisc = {
61 	&mod_miscops, "tod module for Mostek M48T59"
62 };
63 
64 static struct modlinkage modlinkage = {
65 	MODREV_1, (void *)&modlmisc, NULL
66 };
67 
68 int
69 _init(void)
70 {
71 	if (strcmp(tod_module_name, "todmostek") == 0) {
72 		tod_ops.tod_get = todm_get;
73 		tod_ops.tod_set = todm_set;
74 		tod_ops.tod_set_watchdog_timer = todm_set_watchdog_timer;
75 		tod_ops.tod_clear_watchdog_timer = todm_clear_watchdog_timer;
76 		tod_ops.tod_set_power_alarm = todm_set_power_alarm;
77 		tod_ops.tod_clear_power_alarm = todm_clear_power_alarm;
78 		tod_ops.tod_get_cpufrequency = todm_get_cpufrequency;
79 
80 		/*
81 		 * check if hardware watchdog timer is available and user
82 		 * enabled it.
83 		 */
84 		if (watchdog_enable) {
85 			if (!watchdog_available) {
86 				cmn_err(CE_WARN,
87 				    "Hardware watchdog unavailable");
88 			} else if (boothowto & RB_DEBUG) {
89 				cmn_err(CE_WARN, "Hardware watchdog disabled"
90 				    " [debugger]");
91 			}
92 		}
93 	}
94 
95 	return (mod_install(&modlinkage));
96 }
97 
98 int
99 _fini(void)
100 {
101 	if (strcmp(tod_module_name, "todmostek") == 0)
102 		return (EBUSY);
103 	else
104 		return (mod_remove(&modlinkage));
105 }
106 
107 int
108 _info(struct modinfo *modinfop)
109 {
110 	return (mod_info(&modlinkage, modinfop));
111 }
112 
113 /*
114  * Read the current time from the clock chip and convert to UNIX form.
115  * Assumes that the year in the clock chip is valid.
116  * Must be called with tod_lock held.
117  */
118 static timestruc_t
119 todm_get(void)
120 {
121 	timestruc_t ts;
122 	todinfo_t tod;
123 	int s;
124 
125 	ASSERT(MUTEX_HELD(&tod_lock));
126 
127 	s = splhi();
128 
129 	CLOCK->clk_ctrl |= CLK_CTRL_READ;
130 	tod.tod_year	= BCD_TO_BYTE(CLOCK->clk_year) + YRBASE;
131 	tod.tod_month	= BCD_TO_BYTE(CLOCK->clk_month & 0x1f);
132 	tod.tod_day	= BCD_TO_BYTE(CLOCK->clk_day & 0x3f);
133 	tod.tod_dow	= BCD_TO_BYTE(CLOCK->clk_weekday & 0x7);
134 	tod.tod_hour	= BCD_TO_BYTE(CLOCK->clk_hour & 0x3f);
135 	tod.tod_min	= BCD_TO_BYTE(CLOCK->clk_min & 0x7f);
136 	tod.tod_sec	= BCD_TO_BYTE(CLOCK->clk_sec & 0x7f);
137 	CLOCK->clk_ctrl &= ~CLK_CTRL_READ;
138 
139 	splx(s);
140 
141 	/*
142 	 * Apparently the m48t59 doesn't quite do what the spec sheet says.
143 	 * The spec says reading WRD will reset the timer but that doesn't work.
144 	 * So we need to reload timeout each time we want to reset the timer.
145 	 */
146 	CLOCK->clk_watchdog = watchdog_bits;
147 
148 	ts.tv_sec = tod_to_utc(tod);
149 	ts.tv_nsec = 0;
150 	return (ts);
151 }
152 
153 /*
154  * Write the specified time into the clock chip.
155  * Must be called with tod_lock held.
156  */
157 /* ARGSUSED */
158 static void
159 todm_set(timestruc_t ts)
160 {
161 	todinfo_t tod = utc_to_tod(ts.tv_sec);
162 
163 	ASSERT(MUTEX_HELD(&tod_lock));
164 
165 	CLOCK->clk_ctrl |= CLK_CTRL_WRITE;	/* allow writes */
166 	CLOCK->clk_year		= BYTE_TO_BCD(tod.tod_year - YRBASE);
167 	CLOCK->clk_month	= BYTE_TO_BCD(tod.tod_month);
168 	CLOCK->clk_day		= BYTE_TO_BCD(tod.tod_day);
169 	CLOCK->clk_weekday	= BYTE_TO_BCD(tod.tod_dow);
170 	CLOCK->clk_hour		= BYTE_TO_BCD(tod.tod_hour);
171 	CLOCK->clk_min		= BYTE_TO_BCD(tod.tod_min);
172 	CLOCK->clk_sec		= BYTE_TO_BCD(tod.tod_sec);
173 	CLOCK->clk_ctrl &= ~CLK_CTRL_WRITE;	/* load values */
174 }
175 
176 
177 /*
178  * Program the watchdog timer shadow register with the specified value.
179  * Setting the timer to zero value means no watchdog timeout.
180  */
181 static uint_t
182 todm_set_watchdog_timer(uint_t timeoutval)
183 {
184 	ASSERT(MUTEX_HELD(&tod_lock));
185 
186 	if (watchdog_enable == 0 || watchdog_available == 0 ||
187 	    (boothowto & RB_DEBUG))
188 		return (0);
189 
190 	watchdog_timeout = timeoutval;
191 	watchdog_bits = CLK_WATCHDOG_BITS(timeoutval);
192 	watchdog_activated = 1;
193 
194 	return (timeoutval);
195 }
196 
197 /*
198  * Clear the hardware timer register. Also zero out the watchdog timer
199  * shadow register.
200  */
201 static uint_t
202 todm_clear_watchdog_timer(void)
203 {
204 	ASSERT(MUTEX_HELD(&tod_lock));
205 
206 	if (watchdog_activated == 0)
207 		return (0);
208 
209 	CLOCK->clk_watchdog = 0;
210 
211 	watchdog_bits = 0;
212 	watchdog_activated = 0;
213 	return (watchdog_timeout);
214 }
215 
216 /*
217  * program the tod registers for alarm to go off at the specified time
218  */
219 static void
220 todm_set_power_alarm(timestruc_t ts)
221 {
222 	todinfo_t	tod;
223 	uchar_t	c;
224 
225 	ASSERT(MUTEX_HELD(&tod_lock));
226 	tod = utc_to_tod(ts.tv_sec);
227 
228 	c = CLOCK->clk_flags; /* clear alarm intr flag by reading the reg */
229 #ifdef lint
230 	CLOCK->clk_flags = c;
231 #endif
232 	CLOCK->clk_interrupts &= ~CLK_ALARM_ENABLE; /* disable alarm intr */
233 
234 	CLOCK->clk_day &= ~CLK_FREQT; /* keep Freqency Test bit cleared */
235 
236 	CLOCK->clk_alm_day = BYTE_TO_BCD(tod.tod_day);
237 	CLOCK->clk_alm_hours = BYTE_TO_BCD(tod.tod_hour);
238 	CLOCK->clk_alm_mins = BYTE_TO_BCD(tod.tod_min);
239 	CLOCK->clk_alm_secs = BYTE_TO_BCD(tod.tod_sec);
240 
241 	CLOCK->clk_interrupts |= CLK_ALARM_ENABLE; /* enable alarm intr */
242 }
243 
244 /*
245  * clear alarm interrupt
246  */
247 static void
248 todm_clear_power_alarm()
249 {
250 	uchar_t	c;
251 
252 	ASSERT(MUTEX_HELD(&tod_lock));
253 
254 	c = CLOCK->clk_flags; /* clear alarm intr flag by reading the reg */
255 
256 #ifdef lint
257 	CLOCK->clk_flags = c;
258 #endif
259 
260 	CLOCK->clk_interrupts &= ~CLK_ALARM_ENABLE; /* disable alarm intr */
261 }
262 
263 /*
264  * Determine the cpu frequency by watching the TOD chip rollover twice.
265  * Cpu clock rate is determined by computing the ticks added (in tick register)
266  * during one second interval on TOD.
267  */
268 uint64_t
269 todm_get_cpufrequency(void)
270 {
271 	ASSERT(MUTEX_HELD(&tod_lock));
272 
273 	return (find_cpufrequency(&(TIMECHECK_CLOCK->clk_sec)));
274 }
275