1/*	$NetBSD: clock_pcc.c,v 1.18 2008/01/12 09:54:21 tsutsui Exp $	*/
2
3/*-
4 * Copyright (c) 1996 The NetBSD Foundation, Inc.
5 * All rights reserved.
6 *
7 * This code is derived from software contributed to The NetBSD Foundation
8 * by Jason R. Thorpe.
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 * Glue for the Peripheral Channel Controller timers and the
34 * Mostek clock chip found on the MVME-147.
35 */
36
37#include <sys/cdefs.h>
38__KERNEL_RCSID(0, "$NetBSD: clock_pcc.c,v 1.18 2008/01/12 09:54:21 tsutsui Exp $");
39
40#include <sys/param.h>
41#include <sys/kernel.h>
42#include <sys/systm.h>
43#include <sys/device.h>
44#include <sys/timetc.h>
45
46#include <machine/psl.h>
47#include <machine/bus.h>
48
49#include <dev/mvme/clockvar.h>
50
51#include <mvme68k/dev/pccreg.h>
52#include <mvme68k/dev/pccvar.h>
53
54#include "ioconf.h"
55
56int clock_pcc_match(struct device *, struct cfdata *, void *);
57void clock_pcc_attach(struct device *, struct device *, void *);
58
59struct clock_pcc_softc {
60	struct device sc_dev;
61	struct clock_attach_args sc_clock_args;
62	u_char sc_clock_lvl;
63	struct timecounter sc_tc;
64};
65
66CFATTACH_DECL(clock_pcc, sizeof(struct clock_pcc_softc),
67    clock_pcc_match, clock_pcc_attach, NULL, NULL);
68
69
70static int clock_pcc_profintr(void *);
71static int clock_pcc_statintr(void *);
72static void clock_pcc_initclocks(void *, int, int);
73static u_int clock_pcc_getcount(struct timecounter *);
74static void clock_pcc_shutdown(void *);
75
76static struct clock_pcc_softc *clock_pcc_sc;
77static uint32_t clock_pcc_count;
78static uint16_t clock_pcc_reload;
79
80/* ARGSUSED */
81int
82clock_pcc_match(struct device *parent, struct cfdata *cf, void *aux)
83{
84	struct pcc_attach_args *pa;
85
86	pa = aux;
87
88	/* Only one clock, please. */
89	if (clock_pcc_sc)
90		return 0;
91
92	if (strcmp(pa->pa_name, clock_cd.cd_name))
93		return 0;
94
95	pa->pa_ipl = cf->pcccf_ipl;
96
97	return 1;
98}
99
100/* ARGSUSED */
101void
102clock_pcc_attach(struct device *parent, struct device *self, void *aux)
103{
104	struct pcc_attach_args *pa;
105	struct clock_pcc_softc *sc;
106
107	sc = (struct clock_pcc_softc *)self;
108	pa = aux;
109
110	if (pa->pa_ipl != CLOCK_LEVEL)
111		panic("clock_pcc_attach: wrong interrupt level");
112
113	clock_pcc_sc = sc;
114	sc->sc_clock_args.ca_arg = sc;
115	sc->sc_clock_args.ca_initfunc = clock_pcc_initclocks;
116
117	/* Do common portions of clock config. */
118	clock_config(self, &sc->sc_clock_args, pccintr_evcnt(pa->pa_ipl));
119
120	/* Ensure our interrupts get disabled at shutdown time. */
121	(void)shutdownhook_establish(clock_pcc_shutdown, NULL);
122
123	/* Attach the interrupt handlers. */
124	pccintr_establish(PCCV_TIMER1, clock_pcc_profintr, pa->pa_ipl,
125	    NULL, &clock_profcnt);
126	pccintr_establish(PCCV_TIMER2, clock_pcc_statintr, pa->pa_ipl,
127	    NULL, &clock_statcnt);
128	sc->sc_clock_lvl = pa->pa_ipl | PCC_IENABLE | PCC_TIMERACK;
129}
130
131void
132clock_pcc_initclocks(void *arg, int prof_us, int stat_us)
133{
134	struct clock_pcc_softc *sc = arg;
135
136	clock_pcc_reload = pcc_timer_us2lim(prof_us);
137	pcc_reg_write16(sys_pcc, PCCREG_TMR1_PRELOAD, clock_pcc_reload);
138	pcc_reg_write(sys_pcc, PCCREG_TMR1_CONTROL, PCC_TIMERCLEAR);
139	pcc_reg_write(sys_pcc, PCCREG_TMR1_CONTROL, PCC_TIMERSTART);
140	pcc_reg_write(sys_pcc, PCCREG_TMR1_INTR_CTRL, sc->sc_clock_lvl);
141
142	pcc_reg_write16(sys_pcc, PCCREG_TMR2_PRELOAD,
143	    pcc_timer_us2lim(stat_us));
144	pcc_reg_write(sys_pcc, PCCREG_TMR2_CONTROL, PCC_TIMERCLEAR);
145	pcc_reg_write(sys_pcc, PCCREG_TMR2_CONTROL, PCC_TIMERSTART);
146	pcc_reg_write(sys_pcc, PCCREG_TMR2_INTR_CTRL, sc->sc_clock_lvl);
147
148	sc->sc_tc.tc_get_timecount = clock_pcc_getcount;
149	sc->sc_tc.tc_name = "pcc_count";
150	sc->sc_tc.tc_frequency = PCC_TIMERFREQ;
151	sc->sc_tc.tc_quality = 100;
152	sc->sc_tc.tc_counter_mask = ~0;
153	tc_init(&sc->sc_tc);
154}
155
156/* ARGSUSED */
157u_int
158clock_pcc_getcount(struct timecounter *tc)
159{
160	u_int cnt;
161	uint16_t tc1, tc2;
162	uint8_t cr;
163	int s;
164
165	s = splhigh();
166
167	/*
168	 * There's no way to latch the counter and overflow registers
169	 * without pausing the clock, so compensate for the possible
170	 * race by checking for counter wrap-around and re-reading the
171	 * overflow counter if necessary.
172	 *
173	 * Note: This only works because we're at splhigh().
174	 */
175	tc1 = pcc_reg_read16(sys_pcc, PCCREG_TMR1_COUNT);
176	cr = pcc_reg_read(sys_pcc, PCCREG_TMR1_CONTROL);
177	tc2 = pcc_reg_read16(sys_pcc, PCCREG_TMR1_COUNT);
178	if (tc1 > tc2) {
179		cr = pcc_reg_read(sys_pcc, PCCREG_TMR1_CONTROL);
180		tc1 = tc2;
181	}
182	cnt = clock_pcc_count;
183	splx(s);
184	/* XXX assume HZ == 100 */
185	cnt += (tc1 - clock_pcc_reload) +
186	    (PCC_TIMERFREQ / 100) * (cr >> PCC_TIMEROVFLSHIFT);
187
188	return cnt;
189}
190
191int
192clock_pcc_profintr(void *frame)
193{
194	uint8_t cr;
195	uint16_t tc;
196	int s;
197
198	s = splhigh();
199	tc = pcc_reg_read16(sys_pcc, PCCREG_TMR1_COUNT);
200	cr = pcc_reg_read(sys_pcc, PCCREG_TMR1_CONTROL);
201	if (tc > pcc_reg_read16(sys_pcc, PCCREG_TMR1_COUNT))
202		cr = pcc_reg_read(sys_pcc, PCCREG_TMR1_CONTROL);
203	pcc_reg_write(sys_pcc, PCCREG_TMR1_CONTROL, PCC_TIMERSTART);
204	pcc_reg_write(sys_pcc, PCCREG_TMR1_INTR_CTRL,
205	    clock_pcc_sc->sc_clock_lvl);
206	splx(s);
207
208	for (cr >>= PCC_TIMEROVFLSHIFT; cr; cr--) {
209		/* XXX assume HZ == 100 */
210		clock_pcc_count += PCC_TIMERFREQ / 100;
211		hardclock(frame);
212	}
213
214	return 1;
215}
216
217int
218clock_pcc_statintr(void *frame)
219{
220
221	/* Disable the timer interrupt while we handle it. */
222	pcc_reg_write(sys_pcc, PCCREG_TMR2_INTR_CTRL, 0);
223
224	statclock((struct clockframe *) frame);
225
226	pcc_reg_write16(sys_pcc, PCCREG_TMR2_PRELOAD,
227	    pcc_timer_us2lim(CLOCK_NEWINT(clock_statvar, clock_statmin)));
228	pcc_reg_write(sys_pcc, PCCREG_TMR2_CONTROL, PCC_TIMERCLEAR);
229	pcc_reg_write(sys_pcc, PCCREG_TMR2_CONTROL, PCC_TIMERSTART);
230
231	pcc_reg_write(sys_pcc, PCCREG_TMR2_INTR_CTRL,
232	    clock_pcc_sc->sc_clock_lvl);
233
234	return 1;
235}
236
237/* ARGSUSED */
238void
239clock_pcc_shutdown(void *arg)
240{
241
242	/* Make sure the timer interrupts are turned off. */
243	pcc_reg_write(sys_pcc, PCCREG_TMR1_CONTROL, PCC_TIMERCLEAR);
244	pcc_reg_write(sys_pcc, PCCREG_TMR1_INTR_CTRL, 0);
245	pcc_reg_write(sys_pcc, PCCREG_TMR2_CONTROL, PCC_TIMERCLEAR);
246	pcc_reg_write(sys_pcc, PCCREG_TMR2_INTR_CTRL, 0);
247}
248