todstarcat.c revision 4135:69588295f961 
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 2004 Sun Microsystems, Inc.  All rights reserved.
23 * Use is subject to license terms.
24 */
25
26#pragma ident	"%Z%%M%	%I%	%E% SMI"
27
28/*
29 * tod driver module for Starcat
30 * This module implements a soft tod since
31 * starcat has no tod part.
32 */
33
34#include <sys/types.h>
35#include <sys/param.h>
36#include <sys/sysmacros.h>
37#include <sys/systm.h>
38#include <sys/errno.h>
39#include <sys/modctl.h>
40#include <sys/autoconf.h>
41#include <sys/debug.h>
42#include <sys/clock.h>
43#include <sys/cmn_err.h>
44#include <sys/promif.h>
45#include <sys/cpuvar.h>
46#include <sys/sunddi.h>
47#include <sys/iosramio.h>
48#include <sys/domaind.h>
49
50#define	abs(x)	((x) < 0 ? -(x) : (x))
51
52#define	TODSC_SET_THRESHOLD	30
53
54static timestruc_t	todsc_get(void);
55static void		todsc_set(timestruc_t);
56static uint_t		todsc_set_watchdog_timer(uint_t);
57static uint_t		todsc_clear_watchdog_timer(void);
58static void		todsc_set_power_alarm(timestruc_t);
59static void		todsc_clear_power_alarm(void);
60static uint64_t		todsc_get_cpufrequency(void);
61
62/*
63 * Module linkage information for the kernel.
64 */
65static struct modlmisc modlmisc = {
66	&mod_miscops, "Soft tod module for Sun Fire 15000"
67};
68
69static struct modlinkage modlinkage = {
70	MODREV_1, (void *)&modlmisc, NULL
71};
72
73static uint32_t heartbeat = 0;
74
75int
76_init(void)
77{
78	if (strcmp(tod_module_name, "todstarcat") == 0) {
79		uint32_t ssc_time32 = 0;
80		char obp_string[40];
81
82		/*
83		 * To obtain the initial start of day time, we use an
84		 * OBP callback; this is because the iosram is not yet
85		 * accessible from the OS at this early stage of startup.
86		 */
87
88		/*
89		 * Set the string to pass to OBP
90		 * for now, we assume we always get a 32bit value
91		 */
92		(void) sprintf(obp_string, "h# %p unix-gettod",
93			(void *) &ssc_time32);
94
95		prom_interpret(obp_string, 0, 0, 0, 0, 0);
96
97		hrestime.tv_sec = (time_t)ssc_time32;
98
99		/*
100		 * A date of zero causes the root filesystem driver
101		 * to try to set the date from the last shutdown.
102		 */
103
104		/*
105		 * Check for a zero date.
106		 */
107		if (ssc_time32 == 0) {
108			cmn_err(CE_WARN, "Initial date is invalid.");
109			cmn_err(CE_CONT, "Attempting to set the date and time "
110				"based on the last shutdown.\n");
111			cmn_err(CE_CONT, "Please inspect the date and time and "
112				"correct if necessary.\n");
113		}
114
115		/*
116		 * Check that the date has not overflowed a 32-bit integer.
117		 */
118		if (TIMESPEC_OVERFLOW(&hrestime)) {
119			cmn_err(CE_WARN, "Date overflow detected.");
120			cmn_err(CE_CONT, "Attempting to set the date and time "
121				"based on the last shutdown.\n");
122			cmn_err(CE_CONT, "Please inspect the date and time and "
123				"correct if necessary.\n");
124
125			hrestime.tv_sec = (time_t)0;
126		}
127
128		tod_ops.tod_get = todsc_get;
129		tod_ops.tod_set = todsc_set;
130		tod_ops.tod_set_watchdog_timer = todsc_set_watchdog_timer;
131		tod_ops.tod_clear_watchdog_timer = todsc_clear_watchdog_timer;
132		tod_ops.tod_set_power_alarm = todsc_set_power_alarm;
133		tod_ops.tod_clear_power_alarm = todsc_clear_power_alarm;
134		tod_ops.tod_get_cpufrequency = todsc_get_cpufrequency;
135
136		/*
137		 * Flag warning if user tried to use hardware watchdog
138		 */
139		if (watchdog_enable) {
140			cmn_err(CE_WARN, "Hardware watchdog unavailable");
141		}
142	}
143
144	return (mod_install(&modlinkage));
145}
146
147int
148_fini(void)
149{
150	if (strcmp(tod_module_name, "todstarcat") == 0)
151		return (EBUSY);
152	else
153		return (mod_remove(&modlinkage));
154}
155
156int
157_info(struct modinfo *modinfop)
158{
159	return (mod_info(&modlinkage, modinfop));
160}
161
162
163/*
164 * Starcat tod_get is simplified to return hrestime and to
165 * update the domain heartbeat.
166 * Must be called with tod_lock held.
167 */
168static timestruc_t
169todsc_get(void)
170{
171	ASSERT(MUTEX_HELD(&tod_lock));
172
173	heartbeat++;
174	(void) iosram_wr(DOMD_MAGIC, DOMD_HEARTBEAT_OFFSET,
175		sizeof (uint32_t), (caddr_t)&heartbeat);
176	return (hrestime);
177}
178
179/*
180 * Must be called with tod_lock held.
181 *
182 * When running NTP, tod_set is called at least once per second in order
183 * to update the hardware clock - for Starcat, we don't want to sync
184 * the non-existent hardware clock, and only want to record significant
185 * time changes on the SC (i.e. when date(1M) is run).  So, we have a
186 * threshold requirement before recording the time change.
187 */
188/* ARGSUSED */
189static void
190todsc_set(timestruc_t ts)
191{
192	char obp_string[40];
193
194	ASSERT(MUTEX_HELD(&tod_lock));
195
196	heartbeat++;
197	(void) iosram_wr(DOMD_MAGIC, DOMD_HEARTBEAT_OFFSET,
198		sizeof (uint32_t), (caddr_t)&heartbeat);
199
200	if (abs(hrestime.tv_sec - ts.tv_sec) > TODSC_SET_THRESHOLD) {
201		/*
202		 * Update the SSC with the new UTC domain time
203		 */
204		(void) sprintf(obp_string, "h# %x unix-settod",
205			(int)ts.tv_sec);
206
207		prom_interpret(obp_string, 0, 0, 0, 0, 0);
208#ifdef DEBUG
209		cmn_err(CE_NOTE, "todsc_set: new domain time 0x%lx\n",
210			ts.tv_sec);
211#endif
212	}
213}
214
215/*
216 * No watchdog function.
217 */
218/* ARGSUSED */
219static uint_t
220todsc_set_watchdog_timer(uint_t timeoutval)
221{
222	ASSERT(MUTEX_HELD(&tod_lock));
223	return (0);
224}
225
226/*
227 * No watchdog function
228 */
229static uint_t
230todsc_clear_watchdog_timer(void)
231{
232	ASSERT(MUTEX_HELD(&tod_lock));
233	return (0);
234}
235
236/*
237 * Null function.
238 */
239/* ARGSUSED */
240static void
241todsc_set_power_alarm(timestruc_t ts)
242{
243	ASSERT(MUTEX_HELD(&tod_lock));
244}
245
246/*
247 * Null function
248 */
249static void
250todsc_clear_power_alarm()
251{
252	ASSERT(MUTEX_HELD(&tod_lock));
253}
254
255/*
256 * Get clock freq from the cpunode.  This function is only called
257 * when use_stick = 0, otherwise, system_clock_freq gets used instead.
258 */
259uint64_t
260todsc_get_cpufrequency(void)
261{
262	return (cpunodes[CPU->cpu_id].clock_freq);
263}
264