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 2010 Sun Microsystems, Inc.  All rights reserved.
23 * Use is subject to license terms.
24 */
25
26#include <sys/param.h>
27#include <sys/time.h>
28#include <sys/systm.h>
29#include <sys/cmn_err.h>
30#include <sys/debug.h>
31#include <sys/clock.h>
32#include <sys/intreg.h>
33#include <sys/x_call.h>
34#include <sys/cpuvar.h>
35#include <sys/promif.h>
36#include <sys/mman.h>
37#include <sys/sysmacros.h>
38#include <sys/lockstat.h>
39#include <vm/as.h>
40#include <vm/hat.h>
41#include <sys/intr.h>
42#include <sys/ivintr.h>
43#include <sys/machsystm.h>
44#include <sys/reboot.h>
45#include <sys/membar.h>
46#include <sys/atomic.h>
47#include <sys/cpu_module.h>
48#include <sys/hypervisor_api.h>
49#include <sys/wdt.h>
50
51uint_t sys_clock_mhz = 0;
52uint64_t sys_tick_freq = 0;
53uint_t cpu_tick_freq = 0;	/* deprecated, tune sys_tick_freq instead */
54uint_t scaled_clock_mhz = 0;
55uint_t nsec_per_sys_tick;
56uint_t sticks_per_usec;
57char clock_started = 0;
58
59void
60clkstart(void)
61{
62	/*
63	 * Now is a good time to activate hardware watchdog.
64	 */
65	watchdog_init();
66}
67
68/*
69 * preset the delay constant for drv_usecwait(). This is done for early
70 * use of the le or scsi drivers in the kernel. The default contant
71 * might be too high early on. We can get a pretty good approximation
72 * of this by setting it as:
73 *
74 * 	sys_clock_mhz = (sys_tick_freq + 500000) / 1000000
75 *
76 * setcpudelay is called twice during the boot process. The first time
77 * is before the TOD driver is loaded so cpu_init_tick_freq cannot
78 * calibrate sys_tick_freq but can only set it to the prom value. The
79 * first call is also before /etc/system is read.
80 *
81 * Only call cpu_init_tick_freq the second time around if sys_tick_freq
82 * has not been tuned via /etc/system.
83 */
84void
85setcpudelay(void)
86{
87	static uint64_t sys_tick_freq_save = 0;
88	/*
89	 * We want to allow cpu_tick_freq to be tunable; we'll only set it
90	 * if it hasn't been explicitly tuned.
91	 */
92	if (cpu_tick_freq != 0) {
93		cmn_err(CE_WARN, "cpu_tick_freq is no longer a kernel "
94		    "tunable, use sys_tick_freq instead");
95		sys_tick_freq = cpu_tick_freq;
96	}
97	if (sys_tick_freq == sys_tick_freq_save) {
98		cpu_init_tick_freq();
99		sys_tick_freq_save = sys_tick_freq;
100	}
101	ASSERT(sys_tick_freq != 0);
102
103	/*
104	 * See the comments in clock.h for a full description of
105	 * nsec_scale.  The "& ~1" operation below ensures that
106	 * nsec_scale is always even, so that for *any* value of
107	 * %tick, multiplying by nsec_scale clears NPT for free.
108	 */
109	nsec_scale = (uint_t)(((u_longlong_t)NANOSEC << (32 - nsec_shift)) /
110	    sys_tick_freq) & ~1;
111
112	/*
113	 * scaled_clock_mhz is a more accurated (ie not rounded-off)
114	 * version of sys_clock_mhz that we used to program the tick
115	 * compare register. Just in case sys_tick_freq is like 142.5 Mhz
116	 * instead of some whole number like 143
117	 */
118
119	scaled_clock_mhz = (sys_tick_freq) / 1000;
120	sys_clock_mhz = (sys_tick_freq + 500000) / 1000000;
121
122	nsec_per_sys_tick = NANOSEC / sys_tick_freq;
123
124	/*
125	 * Pre-calculate number of sticks per usec for drv_usecwait.
126	 */
127	sticks_per_usec = MAX((sys_tick_freq + (MICROSEC - 1)) / MICROSEC, 1);
128
129	if (sys_clock_mhz <= 0) {
130		cmn_err(CE_WARN, "invalid system frequency");
131	}
132}
133
134/*
135 * Hypervisor can return one of two error conditions
136 * for the TOD_GET API call. 1) H_ENOTSUPPORTED 2) H_EWOULDBLOCK
137 *
138 * To handle the H_ENOTSUPPORTED we return 0 seconds and let clkset
139 * set tod_broken.
140 * To handle the H_EWOULDBLOCK we retry for about 500usec and
141 * return hrestime if we can't successfully get a value.
142 */
143timestruc_t
144tod_get(void)
145{
146	timestruc_t ts;
147	uint64_t seconds;
148	int i;
149	unsigned int spl_old;
150	uint64_t ret;
151
152	/*
153	 * Make sure we don't get preempted
154	 * while getting the tod value.
155	 * getting preempted could mean we always
156	 * hit the hypervisor during an update
157	 * and always get EWOULDBLOCK.
158	 */
159
160	spl_old = ddi_enter_critical();
161	for (i = 0; i <= HV_TOD_RETRY_THRESH; i++) {
162		ret = hv_tod_get(&seconds);
163
164		if (ret != H_EWOULDBLOCK)
165			break;
166		drv_usecwait(HV_TOD_WAIT_USEC);
167	}
168	ddi_exit_critical(spl_old);
169
170	ts.tv_nsec = 0;
171	if (ret != H_EOK) {
172
173		switch (ret) {
174		default:
175			cmn_err(CE_WARN,
176			    "tod_get: unknown error from hv_tod_get, %lx\n",
177			    ret);
178			/*FALLTHRU*/
179		case H_EWOULDBLOCK:
180			/*
181			 * We timed out
182			 */
183			tod_status_set(TOD_GET_FAILED);
184			ts.tv_sec = tod_validate(hrestime.tv_sec);
185			break;
186
187		case H_ENOTSUPPORTED:
188			ts.tv_sec = 0;
189			break;
190		};
191	} else {
192		ts.tv_sec = tod_validate(seconds);
193	}
194
195	return (ts);
196}
197
198extern void tod_set_prev(timestruc_t);
199
200/*ARGSUSED*/
201void
202tod_set(timestruc_t ts)
203{
204	int i;
205	uint64_t ret;
206
207	/* for tod_validate() */
208	tod_set_prev(ts);
209
210	for (i = 0; i <= HV_TOD_RETRY_THRESH; i++) {
211		ret = hv_tod_set(ts.tv_sec);
212		if (ret != H_EWOULDBLOCK)
213			break;
214		drv_usecwait(HV_TOD_WAIT_USEC);
215	}
216
217	if (ret != H_EOK && ret != H_ENOTSUPPORTED && ret != H_EWOULDBLOCK)
218		cmn_err(CE_WARN,
219		    "tod_set: Unknown error from hv_tod_set, err %lx", ret);
220	else
221		/* TOD was modified */
222		tod_status_set(TOD_SET_DONE);
223}
224
225/*
226 * The following wrappers have been added so that locking
227 * can be exported to platform-independent clock routines
228 * (ie adjtime(), clock_setttime()), via a functional interface.
229 */
230int
231hr_clock_lock(void)
232{
233	ushort_t s;
234
235	CLOCK_LOCK(&s);
236	return (s);
237}
238
239void
240hr_clock_unlock(int s)
241{
242	CLOCK_UNLOCK(s);
243}
244
245/*
246 * We don't share the trap table with the prom, so we don't need
247 * to enable/disable its clock.
248 */
249void
250mon_clock_init(void)
251{}
252
253void
254mon_clock_start(void)
255{}
256
257void
258mon_clock_stop(void)
259{}
260
261void
262mon_clock_share(void)
263{}
264
265void
266mon_clock_unshare(void)
267{}
268