1 /* $NetBSD: ixp425_timer.c,v 1.11 2006/04/10 03:36:03 simonb Exp $ */
2
3 /*
4 * Copyright (c) 2003
5 * Ichiro FUKUHARA <ichiro@ichiro.org>.
6 * All rights reserved.
7 *
8 * Redistribution and use in source and binary forms, with or without
9 * modification, are permitted provided that the following conditions
10 * are met:
11 * 1. Redistributions of source code must retain the above copyright
12 * notice, this list of conditions and the following disclaimer.
13 * 2. Redistributions in binary form must reproduce the above copyright
14 * notice, this list of conditions and the following disclaimer in the
15 * documentation and/or other materials provided with the distribution.
16 * 3. All advertising materials mentioning features or use of this software
17 * must display the following acknowledgement:
18 * This product includes software developed by Ichiro FUKUHARA.
19 * 4. The name of the company nor the name of the author may be used to
20 * endorse or promote products derived from this software without specific
21 * prior written permission.
22 *
23 * THIS SOFTWARE IS PROVIDED BY ICHIRO FUKUHARA ``AS IS'' AND ANY EXPRESS OR
24 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
25 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
26 * IN NO EVENT SHALL ICHIRO FUKUHARA OR THE VOICES IN HIS HEAD BE LIABLE FOR
27 * 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
36 #include <sys/cdefs.h>
37 __FBSDID("$FreeBSD$");
38
39 #include <sys/param.h>
40 #include <sys/systm.h>
41 #include <sys/kernel.h>
42 #include <sys/module.h>
43 #include <sys/time.h>
44 #include <sys/bus.h>
45 #include <sys/resource.h>
46 #include <sys/rman.h>
47 #include <sys/timetc.h>
48
49 #include <machine/armreg.h>
50 #include <machine/bus.h>
51 #include <machine/cpu.h>
52 #include <machine/cpufunc.h>
53 #include <machine/frame.h>
54 #include <machine/resource.h>
55 #include <machine/intr.h>
56 #include <arm/xscale/ixp425/ixp425reg.h>
57 #include <arm/xscale/ixp425/ixp425var.h>
58
59 static uint32_t counts_per_hz;
60
61 /* callback functions for intr_functions */
62 int ixpclk_intr(void *);
63
64 struct ixpclk_softc {
65 device_t sc_dev;
66 bus_addr_t sc_baseaddr;
67 bus_space_tag_t sc_iot;
68 bus_space_handle_t sc_ioh;
69 };
70
71 static unsigned ixp425_timer_get_timecount(struct timecounter *tc);
72
73 #ifndef IXP425_CLOCK_FREQ
74 #define COUNTS_PER_SEC 66666600 /* 66MHz */
75 #else
76 #define COUNTS_PER_SEC IXP425_CLOCK_FREQ
77 #endif
78 #define COUNTS_PER_USEC ((COUNTS_PER_SEC / 1000000) + 1)
79
80 static struct ixpclk_softc *ixpclk_sc = NULL;
81
82 #define GET_TS_VALUE(sc) (*(volatile u_int32_t *) \
83 (IXP425_TIMER_VBASE + IXP425_OST_TS))
84
85 static struct timecounter ixp425_timer_timecounter = {
86 ixp425_timer_get_timecount, /* get_timecount */
87 NULL, /* no poll_pps */
88 ~0u, /* counter_mask */
89 COUNTS_PER_SEC, /* frequency */
90 "IXP4XX Timer", /* name */
91 1000, /* quality */
92 };
93
94 static int
ixpclk_probe(device_t dev)95 ixpclk_probe(device_t dev)
96 {
97 device_set_desc(dev, "IXP4XX Timer");
98 return (0);
99 }
100
101 static int
ixpclk_attach(device_t dev)102 ixpclk_attach(device_t dev)
103 {
104 struct ixpclk_softc *sc = device_get_softc(dev);
105 struct ixp425_softc *sa = device_get_softc(device_get_parent(dev));
106
107 ixpclk_sc = sc;
108
109 sc->sc_dev = dev;
110 sc->sc_iot = sa->sc_iot;
111 sc->sc_baseaddr = IXP425_TIMER_HWBASE;
112
113 if (bus_space_map(sc->sc_iot, sc->sc_baseaddr, 8, 0,
114 &sc->sc_ioh))
115 panic("%s: Cannot map registers", device_get_name(dev));
116
117 return (0);
118 }
119
120 static device_method_t ixpclk_methods[] = {
121 DEVMETHOD(device_probe, ixpclk_probe),
122 DEVMETHOD(device_attach, ixpclk_attach),
123 {0, 0},
124 };
125
126 static driver_t ixpclk_driver = {
127 "ixpclk",
128 ixpclk_methods,
129 sizeof(struct ixpclk_softc),
130 };
131 static devclass_t ixpclk_devclass;
132
133 DRIVER_MODULE(ixpclk, ixp, ixpclk_driver, ixpclk_devclass, 0, 0);
134 static unsigned
ixp425_timer_get_timecount(struct timecounter * tc)135 ixp425_timer_get_timecount(struct timecounter *tc)
136 {
137 uint32_t ret;
138
139 ret = GET_TS_VALUE(sc);
140 return (ret);
141 }
142
143 /*
144 * cpu_initclocks:
145 *
146 * Initialize the clock and get them going.
147 */
148 void
cpu_initclocks(void)149 cpu_initclocks(void)
150 {
151 struct ixpclk_softc* sc = ixpclk_sc;
152 struct resource *irq;
153 device_t dev = sc->sc_dev;
154 u_int oldirqstate;
155 int rid = 0;
156 void *ihl;
157
158 if (hz < 50 || COUNTS_PER_SEC % hz) {
159 printf("Cannot get %d Hz clock; using 100 Hz\n", hz);
160 hz = 100;
161 }
162 tick = 1000000 / hz; /* number of microseconds between interrupts */
163
164 /*
165 * We only have one timer available; stathz and profhz are
166 * always left as 0 (the upper-layer clock code deals with
167 * this situation).
168 */
169 if (stathz != 0)
170 printf("Cannot get %d Hz statclock\n", stathz);
171 stathz = 0;
172
173 if (profhz != 0)
174 printf("Cannot get %d Hz profclock\n", profhz);
175 profhz = 0;
176
177 /* Report the clock frequency. */
178
179 oldirqstate = disable_interrupts(PSR_I);
180
181 irq = bus_alloc_resource(dev, SYS_RES_IRQ, &rid, IXP425_INT_TMR0,
182 IXP425_INT_TMR0, 1, RF_ACTIVE);
183 if (!irq)
184 panic("Unable to setup the clock irq handler.\n");
185 else
186 bus_setup_intr(dev, irq, INTR_TYPE_CLK, ixpclk_intr, NULL,
187 NULL, &ihl);
188
189 /* Set up the new clock parameters. */
190
191 /* clear interrupt */
192 bus_space_write_4(sc->sc_iot, sc->sc_ioh, IXP425_OST_STATUS,
193 OST_WARM_RESET | OST_WDOG_INT | OST_TS_INT |
194 OST_TIM1_INT | OST_TIM0_INT);
195
196 counts_per_hz = COUNTS_PER_SEC / hz;
197
198 /* reload value & Timer enable */
199 bus_space_write_4(sc->sc_iot, sc->sc_ioh, IXP425_OST_TIM0_RELOAD,
200 (counts_per_hz & TIMERRELOAD_MASK) | OST_TIMER_EN);
201
202 tc_init(&ixp425_timer_timecounter);
203 restore_interrupts(oldirqstate);
204 rid = 0;
205 }
206
207
208 /*
209 * DELAY:
210 *
211 * Delay for at least N microseconds.
212 */
213 void
DELAY(int n)214 DELAY(int n)
215 {
216 u_int32_t first, last;
217 int usecs;
218
219 if (n == 0)
220 return;
221
222 /*
223 * Clamp the timeout at a maximum value (about 32 seconds with
224 * a 66MHz clock). *Nobody* should be delay()ing for anywhere
225 * near that length of time and if they are, they should be hung
226 * out to dry.
227 */
228 if (n >= (0x80000000U / COUNTS_PER_USEC))
229 usecs = (0x80000000U / COUNTS_PER_USEC) - 1;
230 else
231 usecs = n * COUNTS_PER_USEC;
232
233 /* Note: Timestamp timer counts *up*, unlike the other timers */
234 first = GET_TS_VALUE();
235
236 while (usecs > 0) {
237 last = GET_TS_VALUE();
238 usecs -= (int)(last - first);
239 first = last;
240 }
241 }
242
243 /*
244 * ixpclk_intr:
245 *
246 * Handle the hardclock interrupt.
247 */
248 int
ixpclk_intr(void * arg)249 ixpclk_intr(void *arg)
250 {
251 struct ixpclk_softc* sc = ixpclk_sc;
252 struct trapframe *frame = arg;
253
254 bus_space_write_4(sc->sc_iot, sc->sc_ioh, IXP425_OST_STATUS,
255 OST_TIM0_INT);
256
257 hardclock(TRAPF_USERMODE(frame), TRAPF_PC(frame));
258 return (FILTER_HANDLED);
259 }
260
261 void
cpu_startprofclock(void)262 cpu_startprofclock(void)
263 {
264 }
265
266 void
cpu_stopprofclock(void)267 cpu_stopprofclock(void)
268 {
269 }
270