xref: /freebsd/sys/arm/arm/sp804.c (revision 19261079)
1 /*-
2  * SPDX-License-Identifier: BSD-2-Clause-FreeBSD
3  *
4  * Copyright (c) 2012 Oleksandr Tymoshenko <gonzo@freebsd.org>
5  * Copyright (c) 2012 Damjan Marion <dmarion@freebsd.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  *
17  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
18  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
21  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
22  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
23  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
24  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
25  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
26  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
27  * SUCH DAMAGE.
28  */
29 
30 #include <sys/cdefs.h>
31 __FBSDID("$FreeBSD$");
32 
33 #include <sys/param.h>
34 #include <sys/systm.h>
35 #include <sys/bus.h>
36 #include <sys/kernel.h>
37 #include <sys/module.h>
38 #include <sys/malloc.h>
39 
40 #include <sys/timeet.h>
41 #include <sys/timetc.h>
42 #include <sys/watchdog.h>
43 #include <machine/bus.h>
44 #include <machine/cpu.h>
45 #include <machine/intr.h>
46 
47 #include <machine/machdep.h> /* For arm_set_delay */
48 
49 #include <dev/ofw/openfirm.h>
50 #include <dev/ofw/ofw_bus.h>
51 #include <dev/ofw/ofw_bus_subr.h>
52 
53 #include <machine/bus.h>
54 
55 #define	SP804_TIMER1_LOAD	0x00
56 #define	SP804_TIMER1_VALUE	0x04
57 #define	SP804_TIMER1_CONTROL	0x08
58 #define		TIMER_CONTROL_EN	(1 << 7)
59 #define		TIMER_CONTROL_FREERUN	(0 << 6)
60 #define		TIMER_CONTROL_PERIODIC	(1 << 6)
61 #define		TIMER_CONTROL_INTREN	(1 << 5)
62 #define		TIMER_CONTROL_DIV1	(0 << 2)
63 #define		TIMER_CONTROL_DIV16	(1 << 2)
64 #define		TIMER_CONTROL_DIV256	(2 << 2)
65 #define		TIMER_CONTROL_32BIT	(1 << 1)
66 #define		TIMER_CONTROL_ONESHOT	(1 << 0)
67 #define	SP804_TIMER1_INTCLR	0x0C
68 #define	SP804_TIMER1_RIS	0x10
69 #define	SP804_TIMER1_MIS	0x14
70 #define	SP804_TIMER1_BGLOAD	0x18
71 #define	SP804_TIMER2_LOAD	0x20
72 #define	SP804_TIMER2_VALUE	0x24
73 #define	SP804_TIMER2_CONTROL	0x28
74 #define	SP804_TIMER2_INTCLR	0x2C
75 #define	SP804_TIMER2_RIS	0x30
76 #define	SP804_TIMER2_MIS	0x34
77 #define	SP804_TIMER2_BGLOAD	0x38
78 
79 #define	SP804_PERIPH_ID0	0xFE0
80 #define	SP804_PERIPH_ID1	0xFE4
81 #define	SP804_PERIPH_ID2	0xFE8
82 #define	SP804_PERIPH_ID3	0xFEC
83 #define	SP804_PRIMECELL_ID0	0xFF0
84 #define	SP804_PRIMECELL_ID1	0xFF4
85 #define	SP804_PRIMECELL_ID2	0xFF8
86 #define	SP804_PRIMECELL_ID3	0xFFC
87 
88 #define	DEFAULT_FREQUENCY	1000000
89 /*
90  * QEMU seems to have problem with full frequency
91  */
92 #define	DEFAULT_DIVISOR		16
93 #define	DEFAULT_CONTROL_DIV	TIMER_CONTROL_DIV16
94 
95 struct sp804_timer_softc {
96 	struct resource*	mem_res;
97 	struct resource*	irq_res;
98 	void*			intr_hl;
99 	uint32_t		sysclk_freq;
100 	bus_space_tag_t		bst;
101 	bus_space_handle_t	bsh;
102 	struct timecounter	tc;
103 	bool			et_enabled;
104 	struct eventtimer	et;
105 	int			timer_initialized;
106 };
107 
108 /* Read/Write macros for Timer used as timecounter */
109 #define sp804_timer_tc_read_4(reg)		\
110 	bus_space_read_4(sc->bst, sc->bsh, reg)
111 
112 #define sp804_timer_tc_write_4(reg, val)	\
113 	bus_space_write_4(sc->bst, sc->bsh, reg, val)
114 
115 static unsigned sp804_timer_tc_get_timecount(struct timecounter *);
116 static void sp804_timer_delay(int, void *);
117 
118 static unsigned
119 sp804_timer_tc_get_timecount(struct timecounter *tc)
120 {
121 	struct sp804_timer_softc *sc = tc->tc_priv;
122 	return 0xffffffff - sp804_timer_tc_read_4(SP804_TIMER1_VALUE);
123 }
124 
125 static int
126 sp804_timer_start(struct eventtimer *et, sbintime_t first, sbintime_t period)
127 {
128 	struct sp804_timer_softc *sc = et->et_priv;
129 	uint32_t count, reg;
130 
131 	if (first != 0) {
132 		sc->et_enabled = 1;
133 
134 		count = ((uint32_t)et->et_frequency * first) >> 32;
135 
136 		sp804_timer_tc_write_4(SP804_TIMER2_LOAD, count);
137 		reg = TIMER_CONTROL_32BIT | TIMER_CONTROL_INTREN |
138 		    TIMER_CONTROL_PERIODIC | DEFAULT_CONTROL_DIV |
139 		    TIMER_CONTROL_EN;
140 		sp804_timer_tc_write_4(SP804_TIMER2_CONTROL, reg);
141 
142 		return (0);
143 	}
144 
145 	if (period != 0) {
146 		panic("period");
147 	}
148 
149 	return (EINVAL);
150 }
151 
152 static int
153 sp804_timer_stop(struct eventtimer *et)
154 {
155 	struct sp804_timer_softc *sc = et->et_priv;
156 	uint32_t reg;
157 
158 	sc->et_enabled = 0;
159 	reg = sp804_timer_tc_read_4(SP804_TIMER2_CONTROL);
160 	reg &= ~(TIMER_CONTROL_EN);
161 	sp804_timer_tc_write_4(SP804_TIMER2_CONTROL, reg);
162 
163 	return (0);
164 }
165 
166 static int
167 sp804_timer_intr(void *arg)
168 {
169 	struct sp804_timer_softc *sc = arg;
170 	static uint32_t prev = 0;
171 	uint32_t x = 0;
172 
173 	x = sp804_timer_tc_read_4(SP804_TIMER1_VALUE);
174 
175 	prev =x ;
176 	sp804_timer_tc_write_4(SP804_TIMER2_INTCLR, 1);
177 	if (sc->et_enabled) {
178 		if (sc->et.et_active) {
179 			sc->et.et_event_cb(&sc->et, sc->et.et_arg);
180 		}
181 	}
182 
183 	return (FILTER_HANDLED);
184 }
185 
186 static int
187 sp804_timer_probe(device_t dev)
188 {
189 
190 	if (!ofw_bus_status_okay(dev))
191 		return (ENXIO);
192 
193 	if (ofw_bus_is_compatible(dev, "arm,sp804")) {
194 		device_set_desc(dev, "SP804 System Timer");
195 		return (BUS_PROBE_DEFAULT);
196 	}
197 
198 	return (ENXIO);
199 }
200 
201 static int
202 sp804_timer_attach(device_t dev)
203 {
204 	struct sp804_timer_softc *sc = device_get_softc(dev);
205 	int rid = 0;
206 	int i;
207 	uint32_t id, reg;
208 	phandle_t node;
209 	pcell_t clock;
210 
211 	sc->mem_res = bus_alloc_resource_any(dev, SYS_RES_MEMORY, &rid, RF_ACTIVE);
212 	if (sc->mem_res == NULL) {
213 		device_printf(dev, "could not allocate memory resource\n");
214 		return (ENXIO);
215 	}
216 
217 	sc->bst = rman_get_bustag(sc->mem_res);
218 	sc->bsh = rman_get_bushandle(sc->mem_res);
219 
220 	/* Request the IRQ resources */
221 	sc->irq_res =  bus_alloc_resource_any(dev, SYS_RES_IRQ, &rid, RF_ACTIVE);
222 	if (sc->irq_res == NULL) {
223 		device_printf(dev, "Error: could not allocate irq resources\n");
224 		return (ENXIO);
225 	}
226 
227 	sc->sysclk_freq = DEFAULT_FREQUENCY;
228 	/* Get the base clock frequency */
229 	node = ofw_bus_get_node(dev);
230 	if ((OF_getencprop(node, "clock-frequency", &clock, sizeof(clock))) > 0) {
231 		sc->sysclk_freq = clock;
232 	}
233 
234 	/* Setup and enable the timer */
235 	if (bus_setup_intr(dev, sc->irq_res, INTR_TYPE_CLK,
236 			sp804_timer_intr, NULL, sc,
237 			&sc->intr_hl) != 0) {
238 		bus_release_resource(dev, SYS_RES_IRQ, rid,
239 			sc->irq_res);
240 		device_printf(dev, "Unable to setup the clock irq handler.\n");
241 		return (ENXIO);
242 	}
243 
244 	sp804_timer_tc_write_4(SP804_TIMER1_CONTROL, 0);
245 	sp804_timer_tc_write_4(SP804_TIMER2_CONTROL, 0);
246 
247 	/*
248 	 * Timer 1, timecounter
249 	 */
250 	sc->tc.tc_frequency = sc->sysclk_freq;
251 	sc->tc.tc_name = "SP804-1";
252 	sc->tc.tc_get_timecount = sp804_timer_tc_get_timecount;
253 	sc->tc.tc_poll_pps = NULL;
254 	sc->tc.tc_counter_mask = ~0u;
255 	sc->tc.tc_quality = 1000;
256 	sc->tc.tc_priv = sc;
257 
258 	sp804_timer_tc_write_4(SP804_TIMER1_VALUE, 0xffffffff);
259 	sp804_timer_tc_write_4(SP804_TIMER1_LOAD, 0xffffffff);
260 	reg = TIMER_CONTROL_PERIODIC | TIMER_CONTROL_32BIT;
261 	sp804_timer_tc_write_4(SP804_TIMER1_CONTROL, reg);
262 	reg |= TIMER_CONTROL_EN;
263 	sp804_timer_tc_write_4(SP804_TIMER1_CONTROL, reg);
264 	tc_init(&sc->tc);
265 
266 	/*
267 	 * Timer 2, event timer
268 	 */
269 	sc->et_enabled = 0;
270 	sc->et.et_name = "SP804-2";
271 	sc->et.et_flags = ET_FLAGS_PERIODIC | ET_FLAGS_ONESHOT;
272 	sc->et.et_quality = 1000;
273 	sc->et.et_frequency = sc->sysclk_freq / DEFAULT_DIVISOR;
274 	sc->et.et_min_period = (0x00000002LLU << 32) / sc->et.et_frequency;
275 	sc->et.et_max_period = (0xfffffffeLLU << 32) / sc->et.et_frequency;
276 	sc->et.et_start = sp804_timer_start;
277 	sc->et.et_stop = sp804_timer_stop;
278 	sc->et.et_priv = sc;
279 	et_register(&sc->et);
280 
281 	id = 0;
282 	for (i = 3; i >= 0; i--) {
283 		id = (id << 8) |
284 		     (sp804_timer_tc_read_4(SP804_PERIPH_ID0 + i*4) & 0xff);
285 	}
286 
287 	device_printf(dev, "peripheral ID: %08x\n", id);
288 
289 	id = 0;
290 	for (i = 3; i >= 0; i--) {
291 		id = (id << 8) |
292 		     (sp804_timer_tc_read_4(SP804_PRIMECELL_ID0 + i*4) & 0xff);
293 	}
294 
295 	arm_set_delay(sp804_timer_delay, sc);
296 
297 	device_printf(dev, "PrimeCell ID: %08x\n", id);
298 
299 	sc->timer_initialized = 1;
300 
301 	return (0);
302 }
303 
304 static device_method_t sp804_timer_methods[] = {
305 	DEVMETHOD(device_probe,		sp804_timer_probe),
306 	DEVMETHOD(device_attach,	sp804_timer_attach),
307 	{ 0, 0 }
308 };
309 
310 static driver_t sp804_timer_driver = {
311 	"timer",
312 	sp804_timer_methods,
313 	sizeof(struct sp804_timer_softc),
314 };
315 
316 static devclass_t sp804_timer_devclass;
317 
318 DRIVER_MODULE(sp804_timer, simplebus, sp804_timer_driver, sp804_timer_devclass, 0, 0);
319 
320 static void
321 sp804_timer_delay(int usec, void *arg)
322 {
323 	struct sp804_timer_softc *sc = arg;
324 	int32_t counts;
325 	uint32_t first, last;
326 
327 	/* Get the number of times to count */
328 	counts = usec * ((sc->tc.tc_frequency / 1000000) + 1);
329 
330 	first = sp804_timer_tc_get_timecount(&sc->tc);
331 
332 	while (counts > 0) {
333 		last = sp804_timer_tc_get_timecount(&sc->tc);
334 		if (last == first)
335 			continue;
336 		if (last > first) {
337 			counts -= (int32_t)(last - first);
338 		} else {
339 			counts -= (int32_t)((0xFFFFFFFF - first) + last);
340 		}
341 		first = last;
342 	}
343 }
344