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: stable/9/sys/arm/xscale/ixp425/ixp425_timer.c 186352 2008-12-20 03:26:09Z sam $");
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/bus.h>
50 #include <machine/cpu.h>
51 #include <machine/cpufunc.h>
52 #include <machine/frame.h>
53 #include <machine/resource.h>
54 #include <machine/intr.h>
55 #include <arm/xscale/ixp425/ixp425reg.h>
56 #include <arm/xscale/ixp425/ixp425var.h>
57
58 static uint32_t counts_per_hz;
59
60 /* callback functions for intr_functions */
61 int ixpclk_intr(void *);
62
63 struct ixpclk_softc {
64 device_t sc_dev;
65 bus_addr_t sc_baseaddr;
66 bus_space_tag_t sc_iot;
67 bus_space_handle_t sc_ioh;
68 };
69
70 static unsigned ixp425_timer_get_timecount(struct timecounter *tc);
71
72 #ifndef IXP425_CLOCK_FREQ
73 #define COUNTS_PER_SEC 66666600 /* 66MHz */
74 #else
75 #define COUNTS_PER_SEC IXP425_CLOCK_FREQ
76 #endif
77 #define COUNTS_PER_USEC ((COUNTS_PER_SEC / 1000000) + 1)
78
79 static struct ixpclk_softc *ixpclk_sc = NULL;
80
81 #define GET_TS_VALUE(sc) (*(volatile u_int32_t *) \
82 (IXP425_TIMER_VBASE + IXP425_OST_TS))
83
84 static struct timecounter ixp425_timer_timecounter = {
85 ixp425_timer_get_timecount, /* get_timecount */
86 NULL, /* no poll_pps */
87 ~0u, /* counter_mask */
88 COUNTS_PER_SEC, /* frequency */
89 "IXP4XX Timer", /* name */
90 1000, /* quality */
91 };
92
93 static int
ixpclk_probe(device_t dev)94 ixpclk_probe(device_t dev)
95 {
96 device_set_desc(dev, "IXP4XX Timer");
97 return (0);
98 }
99
100 static int
ixpclk_attach(device_t dev)101 ixpclk_attach(device_t dev)
102 {
103 struct ixpclk_softc *sc = device_get_softc(dev);
104 struct ixp425_softc *sa = device_get_softc(device_get_parent(dev));
105
106 ixpclk_sc = sc;
107
108 sc->sc_dev = dev;
109 sc->sc_iot = sa->sc_iot;
110 sc->sc_baseaddr = IXP425_TIMER_HWBASE;
111
112 if (bus_space_map(sc->sc_iot, sc->sc_baseaddr, 8, 0,
113 &sc->sc_ioh))
114 panic("%s: Cannot map registers", device_get_name(dev));
115
116 return (0);
117 }
118
119 static device_method_t ixpclk_methods[] = {
120 DEVMETHOD(device_probe, ixpclk_probe),
121 DEVMETHOD(device_attach, ixpclk_attach),
122 {0, 0},
123 };
124
125 static driver_t ixpclk_driver = {
126 "ixpclk",
127 ixpclk_methods,
128 sizeof(struct ixpclk_softc),
129 };
130 static devclass_t ixpclk_devclass;
131
132 DRIVER_MODULE(ixpclk, ixp, ixpclk_driver, ixpclk_devclass, 0, 0);
133 static unsigned
ixp425_timer_get_timecount(struct timecounter * tc)134 ixp425_timer_get_timecount(struct timecounter *tc)
135 {
136 uint32_t ret;
137
138 ret = GET_TS_VALUE(sc);
139 return (ret);
140 }
141
142 /*
143 * cpu_initclocks:
144 *
145 * Initialize the clock and get them going.
146 */
147 void
cpu_initclocks(void)148 cpu_initclocks(void)
149 {
150 struct ixpclk_softc* sc = ixpclk_sc;
151 struct resource *irq;
152 device_t dev = sc->sc_dev;
153 u_int oldirqstate;
154 int rid = 0;
155 void *ihl;
156
157 if (hz < 50 || COUNTS_PER_SEC % hz) {
158 printf("Cannot get %d Hz clock; using 100 Hz\n", hz);
159 hz = 100;
160 }
161 tick = 1000000 / hz; /* number of microseconds between interrupts */
162
163 /*
164 * We only have one timer available; stathz and profhz are
165 * always left as 0 (the upper-layer clock code deals with
166 * this situation).
167 */
168 if (stathz != 0)
169 printf("Cannot get %d Hz statclock\n", stathz);
170 stathz = 0;
171
172 if (profhz != 0)
173 printf("Cannot get %d Hz profclock\n", profhz);
174 profhz = 0;
175
176 /* Report the clock frequency. */
177
178 oldirqstate = disable_interrupts(I32_bit);
179
180 irq = bus_alloc_resource(dev, SYS_RES_IRQ, &rid, IXP425_INT_TMR0,
181 IXP425_INT_TMR0, 1, RF_ACTIVE);
182 if (!irq)
183 panic("Unable to setup the clock irq handler.\n");
184 else
185 bus_setup_intr(dev, irq, INTR_TYPE_CLK, ixpclk_intr, NULL,
186 NULL, &ihl);
187
188 /* Set up the new clock parameters. */
189
190 /* clear interrupt */
191 bus_space_write_4(sc->sc_iot, sc->sc_ioh, IXP425_OST_STATUS,
192 OST_WARM_RESET | OST_WDOG_INT | OST_TS_INT |
193 OST_TIM1_INT | OST_TIM0_INT);
194
195 counts_per_hz = COUNTS_PER_SEC / hz;
196
197 /* reload value & Timer enable */
198 bus_space_write_4(sc->sc_iot, sc->sc_ioh, IXP425_OST_TIM0_RELOAD,
199 (counts_per_hz & TIMERRELOAD_MASK) | OST_TIMER_EN);
200
201 tc_init(&ixp425_timer_timecounter);
202 restore_interrupts(oldirqstate);
203 rid = 0;
204 }
205
206
207 /*
208 * DELAY:
209 *
210 * Delay for at least N microseconds.
211 */
212 void
DELAY(int n)213 DELAY(int n)
214 {
215 u_int32_t first, last;
216 int usecs;
217
218 if (n == 0)
219 return;
220
221 /*
222 * Clamp the timeout at a maximum value (about 32 seconds with
223 * a 66MHz clock). *Nobody* should be delay()ing for anywhere
224 * near that length of time and if they are, they should be hung
225 * out to dry.
226 */
227 if (n >= (0x80000000U / COUNTS_PER_USEC))
228 usecs = (0x80000000U / COUNTS_PER_USEC) - 1;
229 else
230 usecs = n * COUNTS_PER_USEC;
231
232 /* Note: Timestamp timer counts *up*, unlike the other timers */
233 first = GET_TS_VALUE();
234
235 while (usecs > 0) {
236 last = GET_TS_VALUE();
237 usecs -= (int)(last - first);
238 first = last;
239 }
240 }
241
242 /*
243 * ixpclk_intr:
244 *
245 * Handle the hardclock interrupt.
246 */
247 int
ixpclk_intr(void * arg)248 ixpclk_intr(void *arg)
249 {
250 struct ixpclk_softc* sc = ixpclk_sc;
251 struct trapframe *frame = arg;
252
253 bus_space_write_4(sc->sc_iot, sc->sc_ioh, IXP425_OST_STATUS,
254 OST_TIM0_INT);
255
256 hardclock(TRAPF_USERMODE(frame), TRAPF_PC(frame));
257 return (FILTER_HANDLED);
258 }
259
260 void
cpu_startprofclock(void)261 cpu_startprofclock(void)
262 {
263 }
264
265 void
cpu_stopprofclock(void)266 cpu_stopprofclock(void)
267 {
268 }
269