xref: /freebsd/sys/arm/arm/sp804.c (revision fdafd315)
1 /*-
2  * SPDX-License-Identifier: BSD-2-Clause
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/param.h>
31 #include <sys/systm.h>
32 #include <sys/bus.h>
33 #include <sys/kernel.h>
34 #include <sys/module.h>
35 #include <sys/malloc.h>
36 
37 #include <sys/timeet.h>
38 #include <sys/timetc.h>
39 #include <sys/watchdog.h>
40 #include <machine/bus.h>
41 #include <machine/cpu.h>
42 #include <machine/intr.h>
43 
44 #include <machine/machdep.h> /* For arm_set_delay */
45 
46 #include <dev/ofw/openfirm.h>
47 #include <dev/ofw/ofw_bus.h>
48 #include <dev/ofw/ofw_bus_subr.h>
49 
50 #include <machine/bus.h>
51 
52 #define	SP804_TIMER1_LOAD	0x00
53 #define	SP804_TIMER1_VALUE	0x04
54 #define	SP804_TIMER1_CONTROL	0x08
55 #define		TIMER_CONTROL_EN	(1 << 7)
56 #define		TIMER_CONTROL_FREERUN	(0 << 6)
57 #define		TIMER_CONTROL_PERIODIC	(1 << 6)
58 #define		TIMER_CONTROL_INTREN	(1 << 5)
59 #define		TIMER_CONTROL_DIV1	(0 << 2)
60 #define		TIMER_CONTROL_DIV16	(1 << 2)
61 #define		TIMER_CONTROL_DIV256	(2 << 2)
62 #define		TIMER_CONTROL_32BIT	(1 << 1)
63 #define		TIMER_CONTROL_ONESHOT	(1 << 0)
64 #define	SP804_TIMER1_INTCLR	0x0C
65 #define	SP804_TIMER1_RIS	0x10
66 #define	SP804_TIMER1_MIS	0x14
67 #define	SP804_TIMER1_BGLOAD	0x18
68 #define	SP804_TIMER2_LOAD	0x20
69 #define	SP804_TIMER2_VALUE	0x24
70 #define	SP804_TIMER2_CONTROL	0x28
71 #define	SP804_TIMER2_INTCLR	0x2C
72 #define	SP804_TIMER2_RIS	0x30
73 #define	SP804_TIMER2_MIS	0x34
74 #define	SP804_TIMER2_BGLOAD	0x38
75 
76 #define	SP804_PERIPH_ID0	0xFE0
77 #define	SP804_PERIPH_ID1	0xFE4
78 #define	SP804_PERIPH_ID2	0xFE8
79 #define	SP804_PERIPH_ID3	0xFEC
80 #define	SP804_PRIMECELL_ID0	0xFF0
81 #define	SP804_PRIMECELL_ID1	0xFF4
82 #define	SP804_PRIMECELL_ID2	0xFF8
83 #define	SP804_PRIMECELL_ID3	0xFFC
84 
85 #define	DEFAULT_FREQUENCY	1000000
86 /*
87  * QEMU seems to have problem with full frequency
88  */
89 #define	DEFAULT_DIVISOR		16
90 #define	DEFAULT_CONTROL_DIV	TIMER_CONTROL_DIV16
91 
92 struct sp804_timer_softc {
93 	struct resource*	mem_res;
94 	struct resource*	irq_res;
95 	void*			intr_hl;
96 	uint32_t		sysclk_freq;
97 	bus_space_tag_t		bst;
98 	bus_space_handle_t	bsh;
99 	struct timecounter	tc;
100 	bool			et_enabled;
101 	struct eventtimer	et;
102 	int			timer_initialized;
103 };
104 
105 /* Read/Write macros for Timer used as timecounter */
106 #define sp804_timer_tc_read_4(reg)		\
107 	bus_space_read_4(sc->bst, sc->bsh, reg)
108 
109 #define sp804_timer_tc_write_4(reg, val)	\
110 	bus_space_write_4(sc->bst, sc->bsh, reg, val)
111 
112 static unsigned sp804_timer_tc_get_timecount(struct timecounter *);
113 static void sp804_timer_delay(int, void *);
114 
115 static unsigned
sp804_timer_tc_get_timecount(struct timecounter * tc)116 sp804_timer_tc_get_timecount(struct timecounter *tc)
117 {
118 	struct sp804_timer_softc *sc = tc->tc_priv;
119 	return 0xffffffff - sp804_timer_tc_read_4(SP804_TIMER1_VALUE);
120 }
121 
122 static int
sp804_timer_start(struct eventtimer * et,sbintime_t first,sbintime_t period)123 sp804_timer_start(struct eventtimer *et, sbintime_t first, sbintime_t period)
124 {
125 	struct sp804_timer_softc *sc = et->et_priv;
126 	uint32_t count, reg;
127 
128 	if (first != 0) {
129 		sc->et_enabled = 1;
130 
131 		count = ((uint32_t)et->et_frequency * first) >> 32;
132 
133 		sp804_timer_tc_write_4(SP804_TIMER2_LOAD, count);
134 		reg = TIMER_CONTROL_32BIT | TIMER_CONTROL_INTREN |
135 		    TIMER_CONTROL_PERIODIC | DEFAULT_CONTROL_DIV |
136 		    TIMER_CONTROL_EN;
137 		sp804_timer_tc_write_4(SP804_TIMER2_CONTROL, reg);
138 
139 		return (0);
140 	}
141 
142 	if (period != 0) {
143 		panic("period");
144 	}
145 
146 	return (EINVAL);
147 }
148 
149 static int
sp804_timer_stop(struct eventtimer * et)150 sp804_timer_stop(struct eventtimer *et)
151 {
152 	struct sp804_timer_softc *sc = et->et_priv;
153 	uint32_t reg;
154 
155 	sc->et_enabled = 0;
156 	reg = sp804_timer_tc_read_4(SP804_TIMER2_CONTROL);
157 	reg &= ~(TIMER_CONTROL_EN);
158 	sp804_timer_tc_write_4(SP804_TIMER2_CONTROL, reg);
159 
160 	return (0);
161 }
162 
163 static int
sp804_timer_intr(void * arg)164 sp804_timer_intr(void *arg)
165 {
166 	struct sp804_timer_softc *sc = arg;
167 
168 	(void)sp804_timer_tc_read_4(SP804_TIMER1_VALUE);
169 
170 	sp804_timer_tc_write_4(SP804_TIMER2_INTCLR, 1);
171 	if (sc->et_enabled) {
172 		if (sc->et.et_active) {
173 			sc->et.et_event_cb(&sc->et, sc->et.et_arg);
174 		}
175 	}
176 
177 	return (FILTER_HANDLED);
178 }
179 
180 static int
sp804_timer_probe(device_t dev)181 sp804_timer_probe(device_t dev)
182 {
183 
184 	if (!ofw_bus_status_okay(dev))
185 		return (ENXIO);
186 
187 	if (ofw_bus_is_compatible(dev, "arm,sp804")) {
188 		device_set_desc(dev, "SP804 System Timer");
189 		return (BUS_PROBE_DEFAULT);
190 	}
191 
192 	return (ENXIO);
193 }
194 
195 static int
sp804_timer_attach(device_t dev)196 sp804_timer_attach(device_t dev)
197 {
198 	struct sp804_timer_softc *sc = device_get_softc(dev);
199 	int rid = 0;
200 	int i;
201 	uint32_t id, reg;
202 	phandle_t node;
203 	pcell_t clock;
204 
205 	sc->mem_res = bus_alloc_resource_any(dev, SYS_RES_MEMORY, &rid, RF_ACTIVE);
206 	if (sc->mem_res == NULL) {
207 		device_printf(dev, "could not allocate memory resource\n");
208 		return (ENXIO);
209 	}
210 
211 	sc->bst = rman_get_bustag(sc->mem_res);
212 	sc->bsh = rman_get_bushandle(sc->mem_res);
213 
214 	/* Request the IRQ resources */
215 	sc->irq_res =  bus_alloc_resource_any(dev, SYS_RES_IRQ, &rid, RF_ACTIVE);
216 	if (sc->irq_res == NULL) {
217 		device_printf(dev, "Error: could not allocate irq resources\n");
218 		return (ENXIO);
219 	}
220 
221 	sc->sysclk_freq = DEFAULT_FREQUENCY;
222 	/* Get the base clock frequency */
223 	node = ofw_bus_get_node(dev);
224 	if ((OF_getencprop(node, "clock-frequency", &clock, sizeof(clock))) > 0) {
225 		sc->sysclk_freq = clock;
226 	}
227 
228 	/* Setup and enable the timer */
229 	if (bus_setup_intr(dev, sc->irq_res, INTR_TYPE_CLK,
230 			sp804_timer_intr, NULL, sc,
231 			&sc->intr_hl) != 0) {
232 		bus_release_resource(dev, SYS_RES_IRQ, rid,
233 			sc->irq_res);
234 		device_printf(dev, "Unable to setup the clock irq handler.\n");
235 		return (ENXIO);
236 	}
237 
238 	sp804_timer_tc_write_4(SP804_TIMER1_CONTROL, 0);
239 	sp804_timer_tc_write_4(SP804_TIMER2_CONTROL, 0);
240 
241 	/*
242 	 * Timer 1, timecounter
243 	 */
244 	sc->tc.tc_frequency = sc->sysclk_freq;
245 	sc->tc.tc_name = "SP804-1";
246 	sc->tc.tc_get_timecount = sp804_timer_tc_get_timecount;
247 	sc->tc.tc_poll_pps = NULL;
248 	sc->tc.tc_counter_mask = ~0u;
249 	sc->tc.tc_quality = 1000;
250 	sc->tc.tc_priv = sc;
251 
252 	sp804_timer_tc_write_4(SP804_TIMER1_VALUE, 0xffffffff);
253 	sp804_timer_tc_write_4(SP804_TIMER1_LOAD, 0xffffffff);
254 	reg = TIMER_CONTROL_PERIODIC | TIMER_CONTROL_32BIT;
255 	sp804_timer_tc_write_4(SP804_TIMER1_CONTROL, reg);
256 	reg |= TIMER_CONTROL_EN;
257 	sp804_timer_tc_write_4(SP804_TIMER1_CONTROL, reg);
258 	tc_init(&sc->tc);
259 
260 	/*
261 	 * Timer 2, event timer
262 	 */
263 	sc->et_enabled = 0;
264 	sc->et.et_name = "SP804-2";
265 	sc->et.et_flags = ET_FLAGS_PERIODIC | ET_FLAGS_ONESHOT;
266 	sc->et.et_quality = 1000;
267 	sc->et.et_frequency = sc->sysclk_freq / DEFAULT_DIVISOR;
268 	sc->et.et_min_period = (0x00000002LLU << 32) / sc->et.et_frequency;
269 	sc->et.et_max_period = (0xfffffffeLLU << 32) / sc->et.et_frequency;
270 	sc->et.et_start = sp804_timer_start;
271 	sc->et.et_stop = sp804_timer_stop;
272 	sc->et.et_priv = sc;
273 	et_register(&sc->et);
274 
275 	id = 0;
276 	for (i = 3; i >= 0; i--) {
277 		id = (id << 8) |
278 		     (sp804_timer_tc_read_4(SP804_PERIPH_ID0 + i*4) & 0xff);
279 	}
280 
281 	device_printf(dev, "peripheral ID: %08x\n", id);
282 
283 	id = 0;
284 	for (i = 3; i >= 0; i--) {
285 		id = (id << 8) |
286 		     (sp804_timer_tc_read_4(SP804_PRIMECELL_ID0 + i*4) & 0xff);
287 	}
288 
289 	arm_set_delay(sp804_timer_delay, sc);
290 
291 	device_printf(dev, "PrimeCell ID: %08x\n", id);
292 
293 	sc->timer_initialized = 1;
294 
295 	return (0);
296 }
297 
298 static device_method_t sp804_timer_methods[] = {
299 	DEVMETHOD(device_probe,		sp804_timer_probe),
300 	DEVMETHOD(device_attach,	sp804_timer_attach),
301 	{ 0, 0 }
302 };
303 
304 static driver_t sp804_timer_driver = {
305 	"timer",
306 	sp804_timer_methods,
307 	sizeof(struct sp804_timer_softc),
308 };
309 
310 DRIVER_MODULE(sp804_timer, simplebus, sp804_timer_driver, 0, 0);
311 
312 static void
sp804_timer_delay(int usec,void * arg)313 sp804_timer_delay(int usec, void *arg)
314 {
315 	struct sp804_timer_softc *sc = arg;
316 	int32_t counts;
317 	uint32_t first, last;
318 
319 	/* Get the number of times to count */
320 	counts = usec * ((sc->tc.tc_frequency / 1000000) + 1);
321 
322 	first = sp804_timer_tc_get_timecount(&sc->tc);
323 
324 	while (counts > 0) {
325 		last = sp804_timer_tc_get_timecount(&sc->tc);
326 		if (last == first)
327 			continue;
328 		if (last > first) {
329 			counts -= (int32_t)(last - first);
330 		} else {
331 			counts -= (int32_t)((0xFFFFFFFF - first) + last);
332 		}
333 		first = last;
334 	}
335 }
336