xref: /freebsd/sys/arm/ti/am335x/am335x_dmtimer.c (revision c6ec7d31830ab1c80edae95ad5e4b9dba10c47ac)
1 /*-
2  * Copyright (c) 2012 Damjan Marion <dmarion@Freebsd.org>
3  * All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer.
10  * 2. Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in the
12  *    documentation and/or other materials provided with the distribution.
13  *
14  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
15  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
16  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
17  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
18  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
19  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
20  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
21  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
22  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
23  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
24  * SUCH DAMAGE.
25  */
26 
27 #include <sys/cdefs.h>
28 __FBSDID("$FreeBSD$");
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 #include <sys/rman.h>
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/frame.h>
43 #include <machine/intr.h>
44 
45 #include <dev/fdt/fdt_common.h>
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 #include <machine/fdt.h>
52 
53 #include <arm/ti/ti_prcm.h>
54 
55 #define AM335X_NUM_TIMERS	8
56 
57 #define DMTIMER_TIDR		0x00 /* Identification Register */
58 #define DMTIMER_TIOCP_CFG	0x10 /* Timer OCP Configuration Reg */
59 #define DMTIMER_IQR_EOI		0x20 /* Timer IRQ End-Of-Interrupt Reg */
60 #define DMTIMER_IRQSTATUS_RAW	0x24 /* Timer IRQSTATUS Raw Reg */
61 #define DMTIMER_IRQSTATUS	0x28 /* Timer IRQSTATUS Reg */
62 #define DMTIMER_IRQENABLE_SET	0x2c /* Timer IRQSTATUS Set Reg */
63 #define DMTIMER_IRQENABLE_CLR	0x30 /* Timer IRQSTATUS Clear Reg */
64 #define DMTIMER_IRQWAKEEN	0x34 /* Timer IRQ Wakeup Enable Reg */
65 #define DMTIMER_TCLR		0x38 /* Timer Control Register */
66 #define DMTIMER_TCRR		0x3C /* Timer Counter Register */
67 #define DMTIMER_TLDR		0x40 /* Timer Load Reg */
68 #define DMTIMER_TTGR		0x44 /* Timer Trigger Reg */
69 #define DMTIMER_TWPS		0x48 /* Timer Write Posted Status Reg */
70 #define DMTIMER_TMAR		0x4C /* Timer Match Reg */
71 #define DMTIMER_TCAR1		0x50 /* Timer Capture Reg */
72 #define DMTIMER_TSICR		0x54 /* Timer Synchr. Interface Control Reg */
73 #define DMTIMER_TCAR2		0x48 /* Timer Capture Reg */
74 
75 
76 struct am335x_dmtimer_softc {
77 	struct resource *	tmr_mem_res[AM335X_NUM_TIMERS];
78 	struct resource *	tmr_irq_res[AM335X_NUM_TIMERS];
79 	uint32_t		sysclk_freq;
80 	struct am335x_dmtimer {
81 		bus_space_tag_t		bst;
82 		bus_space_handle_t	bsh;
83 		struct eventtimer	et;
84 	} t[AM335X_NUM_TIMERS];
85 };
86 
87 static struct resource_spec am335x_dmtimer_mem_spec[] = {
88 	{ SYS_RES_MEMORY,   0,  RF_ACTIVE },
89 	{ SYS_RES_MEMORY,   1,  RF_ACTIVE },
90 	{ SYS_RES_MEMORY,   2,  RF_ACTIVE },
91 	{ SYS_RES_MEMORY,   3,  RF_ACTIVE },
92 	{ SYS_RES_MEMORY,   4,  RF_ACTIVE },
93 	{ SYS_RES_MEMORY,   5,  RF_ACTIVE },
94 	{ SYS_RES_MEMORY,   6,  RF_ACTIVE },
95 	{ SYS_RES_MEMORY,   7,  RF_ACTIVE },
96 	{ -1,               0,  0 }
97 };
98 static struct resource_spec am335x_dmtimer_irq_spec[] = {
99 	{ SYS_RES_IRQ,      0,  RF_ACTIVE },
100 	{ SYS_RES_IRQ,      1,  RF_ACTIVE },
101 	{ SYS_RES_IRQ,      2,  RF_ACTIVE },
102 	{ SYS_RES_IRQ,      3,  RF_ACTIVE },
103 	{ SYS_RES_IRQ,      4,  RF_ACTIVE },
104 	{ SYS_RES_IRQ,      5,  RF_ACTIVE },
105 	{ SYS_RES_IRQ,      6,  RF_ACTIVE },
106 	{ SYS_RES_IRQ,      7,  RF_ACTIVE },
107 	{ -1,               0,  0 }
108 };
109 
110 static struct am335x_dmtimer *am335x_dmtimer_tc_tmr = NULL;
111 
112 /* Read/Write macros for Timer used as timecounter */
113 #define am335x_dmtimer_tc_read_4(reg)		\
114 	bus_space_read_4(am335x_dmtimer_tc_tmr->bst, \
115 		am335x_dmtimer_tc_tmr->bsh, reg)
116 
117 #define am335x_dmtimer_tc_write_4(reg, val)	\
118 	bus_space_write_4(am335x_dmtimer_tc_tmr->bst, \
119 		am335x_dmtimer_tc_tmr->bsh, reg, val)
120 
121 /* Read/Write macros for Timer used as eventtimer */
122 #define am335x_dmtimer_et_read_4(reg)		\
123 	bus_space_read_4(tmr->bst, tmr->bsh, reg)
124 
125 #define am335x_dmtimer_et_write_4(reg, val)	\
126 	bus_space_write_4(tmr->bst, tmr->bsh, reg, val)
127 
128 static unsigned am335x_dmtimer_tc_get_timecount(struct timecounter *);
129 
130 static struct timecounter am335x_dmtimer_tc = {
131 	.tc_name           = "AM335x Timecounter",
132 	.tc_get_timecount  = am335x_dmtimer_tc_get_timecount,
133 	.tc_poll_pps       = NULL,
134 	.tc_counter_mask   = ~0u,
135 	.tc_frequency      = 0,
136 	.tc_quality        = 1000,
137 };
138 
139 static unsigned
140 am335x_dmtimer_tc_get_timecount(struct timecounter *tc)
141 {
142 	return am335x_dmtimer_tc_read_4(DMTIMER_TCRR);
143 }
144 
145 static int
146 am335x_dmtimer_start(struct eventtimer *et, struct bintime *first,
147               struct bintime *period)
148 {
149 	struct am335x_dmtimer *tmr = (struct am335x_dmtimer *)et->et_priv;
150 	uint32_t load, count;
151 	uint32_t tclr = 0;
152 
153 	if (period != NULL) {
154 		load = (et->et_frequency * (period->frac >> 32)) >> 32;
155 		if (period->sec > 0)
156 			load += et->et_frequency * period->sec;
157 		tclr |= 2; /* autoreload bit */
158 		panic("periodic timer not implemented\n");
159 	} else {
160 		load = 0;
161 	}
162 
163 	if (first != NULL) {
164 		count = (tmr->et.et_frequency * (first->frac >> 32)) >> 32;
165 		if (first->sec != 0)
166 			count += tmr->et.et_frequency * first->sec;
167 	} else {
168 		count = load;
169 	}
170 
171 	/* Reset Timer */
172 	am335x_dmtimer_et_write_4(DMTIMER_TSICR, 2);
173 
174 	/* Wait for reset to complete */
175 	while (am335x_dmtimer_et_read_4(DMTIMER_TIOCP_CFG) & 1);
176 
177 	/* set load value */
178 	am335x_dmtimer_et_write_4(DMTIMER_TLDR, 0xFFFFFFFE - load);
179 
180 	/* set counter value */
181 	am335x_dmtimer_et_write_4(DMTIMER_TCRR, 0xFFFFFFFE - count);
182 
183 	/* enable overflow interrupt */
184 	am335x_dmtimer_et_write_4(DMTIMER_IRQENABLE_SET, 2);
185 
186 	/* start timer(ST) */
187 	tclr |= 1;
188 	am335x_dmtimer_et_write_4(DMTIMER_TCLR, tclr);
189 
190 	return (0);
191 }
192 
193 static int
194 am335x_dmtimer_stop(struct eventtimer *et)
195 {
196 	struct am335x_dmtimer *tmr = (struct am335x_dmtimer *)et->et_priv;
197 
198 	/* Disable all interrupts */
199 	am335x_dmtimer_et_write_4(DMTIMER_IRQENABLE_CLR, 7);
200 
201 	/* Stop Timer */
202 	am335x_dmtimer_et_write_4(DMTIMER_TCLR, 0);
203 
204 	return (0);
205 }
206 
207 static int
208 am335x_dmtimer_intr(void *arg)
209 {
210 	struct am335x_dmtimer *tmr = (struct am335x_dmtimer *)arg;
211 
212 	/* Ack interrupt */
213 	am335x_dmtimer_et_write_4(DMTIMER_IRQSTATUS, 7);
214 	if (tmr->et.et_active)
215 		tmr->et.et_event_cb(&tmr->et, tmr->et.et_arg);
216 
217 	return (FILTER_HANDLED);
218 }
219 
220 static int
221 am335x_dmtimer_probe(device_t dev)
222 {
223 	struct	am335x_dmtimer_softc *sc;
224 	sc = (struct am335x_dmtimer_softc *)device_get_softc(dev);
225 
226 	if (ofw_bus_is_compatible(dev, "ti,am335x-dmtimer")) {
227 		device_set_desc(dev, "AM335x DMTimer");
228 		return(BUS_PROBE_DEFAULT);
229 	}
230 
231 	return (ENXIO);
232 }
233 
234 static int
235 am335x_dmtimer_attach(device_t dev)
236 {
237 	struct am335x_dmtimer_softc *sc = device_get_softc(dev);
238 	void *ihl;
239 	int err;
240 	int i;
241 
242 	if (am335x_dmtimer_tc_tmr != NULL)
243 		return (EINVAL);
244 
245 	/* Get the base clock frequency */
246 	err = ti_prcm_clk_get_source_freq(SYS_CLK, &sc->sysclk_freq);
247 	if (err) {
248 		device_printf(dev, "Error: could not get sysclk frequency\n");
249 		return (ENXIO);
250 	}
251 
252 	/* Request the memory resources */
253 	err = bus_alloc_resources(dev, am335x_dmtimer_mem_spec,
254 		sc->tmr_mem_res);
255 	if (err) {
256 		device_printf(dev, "Error: could not allocate mem resources\n");
257 		return (ENXIO);
258 	}
259 
260 	/* Request the IRQ resources */
261 	err = bus_alloc_resources(dev, am335x_dmtimer_irq_spec,
262 		sc->tmr_irq_res);
263 	if (err) {
264 		device_printf(dev, "Error: could not allocate irq resources\n");
265 		return (ENXIO);
266 	}
267 
268 	for(i=0;i<AM335X_NUM_TIMERS;i++) {
269 		sc->t[i].bst = rman_get_bustag(sc->tmr_mem_res[i]);
270 		sc->t[i].bsh = rman_get_bushandle(sc->tmr_mem_res[i]);
271 	}
272 
273 	/* Configure DMTimer2 and DMTimer3 source and enable them */
274 	err  = ti_prcm_clk_set_source(DMTIMER2_CLK, SYSCLK_CLK);
275 	err |= ti_prcm_clk_enable(DMTIMER2_CLK);
276 	err |= ti_prcm_clk_set_source(DMTIMER3_CLK, SYSCLK_CLK);
277 	err |= ti_prcm_clk_enable(DMTIMER3_CLK);
278 	if (err) {
279 		device_printf(dev, "Error: could not setup timer clock\n");
280 		return (ENXIO);
281 	}
282 
283 	/* Take DMTimer2 for TC */
284 	am335x_dmtimer_tc_tmr = &sc->t[2];
285 
286 	/* Reset Timer */
287 	am335x_dmtimer_tc_write_4(DMTIMER_TSICR, 2);
288 
289 	/* Wait for reset to complete */
290 	while (am335x_dmtimer_tc_read_4(DMTIMER_TIOCP_CFG) & 1);
291 
292 	/* set load value */
293 	am335x_dmtimer_tc_write_4(DMTIMER_TLDR, 0);
294 
295 	/* set counter value */
296 	am335x_dmtimer_tc_write_4(DMTIMER_TCRR, 0);
297 
298 	/* Set Timer autoreload(AR) and start timer(ST) */
299 	am335x_dmtimer_tc_write_4(DMTIMER_TCLR, 3);
300 
301 	am335x_dmtimer_tc.tc_frequency = sc->sysclk_freq;
302 	tc_init(&am335x_dmtimer_tc);
303 
304 	/* Register DMTimer3 as ET */
305 
306 	/* Setup and enable the timer */
307 	if (bus_setup_intr(dev, sc->tmr_irq_res[3], INTR_TYPE_CLK,
308 			am335x_dmtimer_intr, NULL, &sc->t[3], &ihl) != 0) {
309 		bus_release_resources(dev, am335x_dmtimer_irq_spec,
310 			sc->tmr_irq_res);
311 		device_printf(dev, "Unable to setup the clock irq handler.\n");
312 		return (ENXIO);
313 	}
314 
315 	sc->t[3].et.et_name = "AM335x Eventtimer0";
316 	sc->t[3].et.et_flags = ET_FLAGS_PERIODIC | ET_FLAGS_ONESHOT;
317 	sc->t[3].et.et_quality = 1000;
318 	sc->t[3].et.et_frequency = sc->sysclk_freq;
319 	sc->t[3].et.et_min_period.sec = 0;
320 	sc->t[3].et.et_min_period.frac =
321 	    ((0x00000002LLU << 32) / sc->t[3].et.et_frequency) << 32;
322 	sc->t[3].et.et_max_period.sec = 0xfffffff0U / sc->t[3].et.et_frequency;
323 	sc->t[3].et.et_max_period.frac =
324 	    ((0xfffffffeLLU << 32) / sc->t[3].et.et_frequency) << 32;
325 	sc->t[3].et.et_start = am335x_dmtimer_start;
326 	sc->t[3].et.et_stop = am335x_dmtimer_stop;
327 	sc->t[3].et.et_priv = &sc->t[3];
328 	et_register(&sc->t[3].et);
329 
330 	return (0);
331 }
332 
333 static device_method_t am335x_dmtimer_methods[] = {
334 	DEVMETHOD(device_probe,		am335x_dmtimer_probe),
335 	DEVMETHOD(device_attach,	am335x_dmtimer_attach),
336 	{ 0, 0 }
337 };
338 
339 static driver_t am335x_dmtimer_driver = {
340 	"am335x_dmtimer",
341 	am335x_dmtimer_methods,
342 	sizeof(struct am335x_dmtimer_softc),
343 };
344 
345 static devclass_t am335x_dmtimer_devclass;
346 
347 DRIVER_MODULE(am335x_dmtimer, simplebus, am335x_dmtimer_driver, am335x_dmtimer_devclass, 0, 0);
348 MODULE_DEPEND(am335x_dmtimer, am335x_prcm, 1, 1, 1);
349 
350 void
351 cpu_initclocks(void)
352 {
353 	cpu_initclocks_bsp();
354 }
355 
356 void
357 DELAY(int usec)
358 {
359 		int32_t counts;
360 	uint32_t first, last;
361 
362 	if (am335x_dmtimer_tc_tmr == NULL) {
363 		for (; usec > 0; usec--)
364 			for (counts = 200; counts > 0; counts--)
365 				/* Prevent gcc from optimizing  out the loop */
366 				cpufunc_nullop();
367 		return;
368 	}
369 
370 	/* Get the number of times to count */
371 	counts = usec * ((am335x_dmtimer_tc.tc_frequency / 1000000) + 1);
372 
373 	first = am335x_dmtimer_tc_read_4(DMTIMER_TCRR);
374 
375 	while (counts > 0) {
376 		last = am335x_dmtimer_tc_read_4(DMTIMER_TCRR);
377 		if (last>first) {
378 			counts -= (int32_t)(last - first);
379 		} else {
380 			counts -= (int32_t)((0xFFFFFFFF - first) + last);
381 		}
382 		first = last;
383 	}
384 }
385 
386