xref: /freebsd/sys/arm/ti/am335x/am335x_ehrpwm.c (revision cdebaff820b2a4915a16cedfd511823d78aab171)
1 /*-
2  * Copyright (c) 2013 Oleksandr Tymoshenko <gonzo@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/limits.h>
35 #include <sys/lock.h>
36 #include <sys/module.h>
37 #include <sys/mutex.h>
38 #include <sys/resource.h>
39 #include <sys/rman.h>
40 #include <sys/sysctl.h>
41 
42 #include <machine/bus.h>
43 
44 #include <dev/ofw/openfirm.h>
45 #include <dev/ofw/ofw_bus.h>
46 #include <dev/ofw/ofw_bus_subr.h>
47 
48 #include "am335x_pwm.h"
49 
50 /* In ticks */
51 #define	DEFAULT_PWM_PERIOD	1000
52 #define	PWM_CLOCK		100000000UL
53 
54 #define	PWM_LOCK(_sc)		mtx_lock(&(_sc)->sc_mtx)
55 #define	PWM_UNLOCK(_sc)		mtx_unlock(&(_sc)->sc_mtx)
56 #define	PWM_LOCK_INIT(_sc)	mtx_init(&(_sc)->sc_mtx, \
57     device_get_nameunit(_sc->sc_dev), "am335x_ehrpwm softc", MTX_DEF)
58 #define	PWM_LOCK_DESTROY(_sc)	mtx_destroy(&(_sc)->sc_mtx)
59 
60 #define	EPWM_READ2(_sc, reg)	bus_read_2((_sc)->sc_mem_res, reg);
61 #define	EPWM_WRITE2(_sc, reg, value)	\
62     bus_write_2((_sc)->sc_mem_res, reg, value);
63 
64 #define	EPWM_TBCTL		0x00
65 #define		TBCTL_FREERUN		(2 << 14)
66 #define		TBCTL_PHDIR_UP		(1 << 13)
67 #define		TBCTL_PHDIR_DOWN	(0 << 13)
68 #define		TBCTL_CLKDIV(x)		((x) << 10)
69 #define		TBCTL_CLKDIV_MASK	(3 << 10)
70 #define		TBCTL_HSPCLKDIV(x)	((x) << 7)
71 #define		TBCTL_HSPCLKDIV_MASK	(3 << 7)
72 #define		TBCTL_SYNCOSEL_DISABLED	(3 << 4)
73 #define		TBCTL_PRDLD_SHADOW	(0 << 3)
74 #define		TBCTL_PRDLD_IMMEDIATE	(0 << 3)
75 #define		TBCTL_PHSEN_ENABLED	(1 << 2)
76 #define		TBCTL_PHSEN_DISABLED	(0 << 2)
77 #define		TBCTL_CTRMODE_MASK	(3)
78 #define		TBCTL_CTRMODE_UP	(0 << 0)
79 #define		TBCTL_CTRMODE_DOWN	(1 << 0)
80 #define		TBCTL_CTRMODE_UPDOWN	(2 << 0)
81 #define		TBCTL_CTRMODE_FREEZE	(3 << 0)
82 
83 #define	EPWM_TBSTS		0x02
84 #define	EPWM_TBPHSHR		0x04
85 #define	EPWM_TBPHS		0x06
86 #define	EPWM_TBCNT		0x08
87 #define	EPWM_TBPRD		0x0a
88 /* Counter-compare */
89 #define	EPWM_CMPCTL		0x0e
90 #define		CMPCTL_SHDWBMODE_SHADOW		(1 << 6)
91 #define		CMPCTL_SHDWBMODE_IMMEDIATE	(0 << 6)
92 #define		CMPCTL_SHDWAMODE_SHADOW		(1 << 4)
93 #define		CMPCTL_SHDWAMODE_IMMEDIATE	(0 << 4)
94 #define		CMPCTL_LOADBMODE_ZERO		(0 << 2)
95 #define		CMPCTL_LOADBMODE_PRD		(1 << 2)
96 #define		CMPCTL_LOADBMODE_EITHER		(2 << 2)
97 #define		CMPCTL_LOADBMODE_FREEZE		(3 << 2)
98 #define		CMPCTL_LOADAMODE_ZERO		(0 << 0)
99 #define		CMPCTL_LOADAMODE_PRD		(1 << 0)
100 #define		CMPCTL_LOADAMODE_EITHER		(2 << 0)
101 #define		CMPCTL_LOADAMODE_FREEZE		(3 << 0)
102 #define	EPWM_CMPAHR		0x10
103 #define	EPWM_CMPA		0x12
104 #define	EPWM_CMPB		0x14
105 /* CMPCTL_LOADAMODE_ZERO */
106 #define	EPWM_AQCTLA		0x16
107 #define	EPWM_AQCTLB		0x18
108 #define		AQCTL_CBU_NONE		(0 << 8)
109 #define		AQCTL_CBU_CLEAR		(1 << 8)
110 #define		AQCTL_CBU_SET		(2 << 8)
111 #define		AQCTL_CBU_TOGGLE	(3 << 8)
112 #define		AQCTL_CAU_NONE		(0 << 4)
113 #define		AQCTL_CAU_CLEAR		(1 << 4)
114 #define		AQCTL_CAU_SET		(2 << 4)
115 #define		AQCTL_CAU_TOGGLE	(3 << 4)
116 #define		AQCTL_ZRO_NONE		(0 << 0)
117 #define		AQCTL_ZRO_CLEAR		(1 << 0)
118 #define		AQCTL_ZRO_SET		(2 << 0)
119 #define		AQCTL_ZRO_TOGGLE	(3 << 0)
120 #define	EPWM_AQSFRC		0x1a
121 #define	EPWM_AQCSFRC		0x1c
122 
123 /* Trip-Zone module */
124 #define	EPWM_TZCTL		0x28
125 #define	EPWM_TZFLG		0x2C
126 /* High-Resolution PWM */
127 #define	EPWM_HRCTL		0x40
128 #define		HRCTL_DELMODE_BOTH	3
129 #define		HRCTL_DELMODE_FALL	2
130 #define		HRCTL_DELMODE_RISE	1
131 
132 static device_probe_t am335x_ehrpwm_probe;
133 static device_attach_t am335x_ehrpwm_attach;
134 static device_detach_t am335x_ehrpwm_detach;
135 
136 static int am335x_ehrpwm_clkdiv[8] = { 1, 2, 4, 8, 16, 32, 64, 128 };
137 
138 struct am335x_ehrpwm_softc {
139 	device_t		sc_dev;
140 	struct mtx		sc_mtx;
141 	struct resource		*sc_mem_res;
142 	int			sc_mem_rid;
143 	/* sysctl for configuration */
144 	int			sc_pwm_clkdiv;
145 	int			sc_pwm_freq;
146 	struct sysctl_oid	*sc_clkdiv_oid;
147 	struct sysctl_oid	*sc_freq_oid;
148 	struct sysctl_oid	*sc_period_oid;
149 	struct sysctl_oid	*sc_chanA_oid;
150 	struct sysctl_oid	*sc_chanB_oid;
151 	uint32_t		sc_pwm_period;
152 	uint32_t		sc_pwm_dutyA;
153 	uint32_t		sc_pwm_dutyB;
154 };
155 
156 static device_method_t am335x_ehrpwm_methods[] = {
157 	DEVMETHOD(device_probe,		am335x_ehrpwm_probe),
158 	DEVMETHOD(device_attach,	am335x_ehrpwm_attach),
159 	DEVMETHOD(device_detach,	am335x_ehrpwm_detach),
160 
161 	DEVMETHOD_END
162 };
163 
164 static driver_t am335x_ehrpwm_driver = {
165 	"am335x_ehrpwm",
166 	am335x_ehrpwm_methods,
167 	sizeof(struct am335x_ehrpwm_softc),
168 };
169 
170 static devclass_t am335x_ehrpwm_devclass;
171 
172 static void
173 am335x_ehrpwm_freq(struct am335x_ehrpwm_softc *sc)
174 {
175 	int clkdiv;
176 
177 	clkdiv = am335x_ehrpwm_clkdiv[sc->sc_pwm_clkdiv];
178 	sc->sc_pwm_freq = PWM_CLOCK / (1 * clkdiv) / sc->sc_pwm_period;
179 }
180 
181 static int
182 am335x_ehrpwm_sysctl_freq(SYSCTL_HANDLER_ARGS)
183 {
184 	int clkdiv, error, freq, i, period;
185 	struct am335x_ehrpwm_softc *sc;
186 	uint32_t reg;
187 
188 	sc = (struct am335x_ehrpwm_softc *)arg1;
189 
190 	PWM_LOCK(sc);
191 	freq = sc->sc_pwm_freq;
192 	PWM_UNLOCK(sc);
193 
194 	error = sysctl_handle_int(oidp, &freq, sizeof(freq), req);
195 	if (error != 0 || req->newptr == NULL)
196 		return (error);
197 
198 	if (freq > PWM_CLOCK)
199 		freq = PWM_CLOCK;
200 
201 	PWM_LOCK(sc);
202 	if (freq != sc->sc_pwm_freq) {
203 		for (i = nitems(am335x_ehrpwm_clkdiv) - 1; i >= 0; i--) {
204 			clkdiv = am335x_ehrpwm_clkdiv[i];
205 			period = PWM_CLOCK / clkdiv / freq;
206 			if (period > USHRT_MAX)
207 				break;
208 			sc->sc_pwm_clkdiv = i;
209 			sc->sc_pwm_period = period;
210 		}
211 		/* Reset the duty cycle settings. */
212 		sc->sc_pwm_dutyA = 0;
213 		sc->sc_pwm_dutyB = 0;
214 		EPWM_WRITE2(sc, EPWM_CMPA, sc->sc_pwm_dutyA);
215 		EPWM_WRITE2(sc, EPWM_CMPB, sc->sc_pwm_dutyB);
216 		/* Update the clkdiv settings. */
217 		reg = EPWM_READ2(sc, EPWM_TBCTL);
218 		reg &= ~TBCTL_CLKDIV_MASK;
219 		reg |= TBCTL_CLKDIV(sc->sc_pwm_clkdiv);
220 		EPWM_WRITE2(sc, EPWM_TBCTL, reg);
221 		/* Update the period settings. */
222 		EPWM_WRITE2(sc, EPWM_TBPRD, sc->sc_pwm_period - 1);
223 		am335x_ehrpwm_freq(sc);
224 	}
225 	PWM_UNLOCK(sc);
226 
227 	return (0);
228 }
229 
230 static int
231 am335x_ehrpwm_sysctl_clkdiv(SYSCTL_HANDLER_ARGS)
232 {
233 	int error, i, clkdiv;
234 	struct am335x_ehrpwm_softc *sc;
235 	uint32_t reg;
236 
237 	sc = (struct am335x_ehrpwm_softc *)arg1;
238 
239 	PWM_LOCK(sc);
240 	clkdiv = am335x_ehrpwm_clkdiv[sc->sc_pwm_clkdiv];
241 	PWM_UNLOCK(sc);
242 
243 	error = sysctl_handle_int(oidp, &clkdiv, sizeof(clkdiv), req);
244 	if (error != 0 || req->newptr == NULL)
245 		return (error);
246 
247 	PWM_LOCK(sc);
248 	if (clkdiv != am335x_ehrpwm_clkdiv[sc->sc_pwm_clkdiv]) {
249 		for (i = 0; i < nitems(am335x_ehrpwm_clkdiv); i++)
250 			if (clkdiv >= am335x_ehrpwm_clkdiv[i])
251 				sc->sc_pwm_clkdiv = i;
252 
253 		reg = EPWM_READ2(sc, EPWM_TBCTL);
254 		reg &= ~TBCTL_CLKDIV_MASK;
255 		reg |= TBCTL_CLKDIV(sc->sc_pwm_clkdiv);
256 		EPWM_WRITE2(sc, EPWM_TBCTL, reg);
257 		am335x_ehrpwm_freq(sc);
258 	}
259 	PWM_UNLOCK(sc);
260 
261 	return (0);
262 }
263 
264 static int
265 am335x_ehrpwm_sysctl_duty(SYSCTL_HANDLER_ARGS)
266 {
267 	struct am335x_ehrpwm_softc *sc = (struct am335x_ehrpwm_softc*)arg1;
268 	int error;
269 	uint32_t duty;
270 
271 	if (oidp == sc->sc_chanA_oid)
272 		duty = sc->sc_pwm_dutyA;
273 	else
274 		duty = sc->sc_pwm_dutyB;
275 	error = sysctl_handle_int(oidp, &duty, 0, req);
276 
277 	if (error != 0 || req->newptr == NULL)
278 		return (error);
279 
280 	if (duty > sc->sc_pwm_period) {
281 		device_printf(sc->sc_dev, "Duty cycle can't be greater then period\n");
282 		return (EINVAL);
283 	}
284 
285 	PWM_LOCK(sc);
286 	if (oidp == sc->sc_chanA_oid) {
287 		sc->sc_pwm_dutyA = duty;
288 		EPWM_WRITE2(sc, EPWM_CMPA, sc->sc_pwm_dutyA);
289 	}
290 	else {
291 		sc->sc_pwm_dutyB = duty;
292 		EPWM_WRITE2(sc, EPWM_CMPB, sc->sc_pwm_dutyB);
293 	}
294 	PWM_UNLOCK(sc);
295 
296 	return (error);
297 }
298 
299 static int
300 am335x_ehrpwm_sysctl_period(SYSCTL_HANDLER_ARGS)
301 {
302 	struct am335x_ehrpwm_softc *sc = (struct am335x_ehrpwm_softc*)arg1;
303 	int error;
304 	uint32_t period;
305 
306 	period = sc->sc_pwm_period;
307 	error = sysctl_handle_int(oidp, &period, 0, req);
308 
309 	if (error != 0 || req->newptr == NULL)
310 		return (error);
311 
312 	if (period < 1)
313 		return (EINVAL);
314 
315 	if (period > USHRT_MAX)
316 		period = USHRT_MAX;
317 
318 	PWM_LOCK(sc);
319 	/* Reset the duty cycle settings. */
320 	sc->sc_pwm_dutyA = 0;
321 	sc->sc_pwm_dutyB = 0;
322 	EPWM_WRITE2(sc, EPWM_CMPA, sc->sc_pwm_dutyA);
323 	EPWM_WRITE2(sc, EPWM_CMPB, sc->sc_pwm_dutyB);
324 	/* Update the period settings. */
325 	sc->sc_pwm_period = period;
326 	EPWM_WRITE2(sc, EPWM_TBPRD, period - 1);
327 	am335x_ehrpwm_freq(sc);
328 	PWM_UNLOCK(sc);
329 
330 	return (error);
331 }
332 
333 static int
334 am335x_ehrpwm_probe(device_t dev)
335 {
336 
337 	if (!ofw_bus_status_okay(dev))
338 		return (ENXIO);
339 
340 	if (!ofw_bus_is_compatible(dev, "ti,am33xx-ehrpwm"))
341 		return (ENXIO);
342 
343 	device_set_desc(dev, "AM335x EHRPWM");
344 
345 	return (BUS_PROBE_DEFAULT);
346 }
347 
348 static int
349 am335x_ehrpwm_attach(device_t dev)
350 {
351 	struct am335x_ehrpwm_softc *sc;
352 	uint32_t reg;
353 	struct sysctl_ctx_list *ctx;
354 	struct sysctl_oid *tree;
355 
356 	sc = device_get_softc(dev);
357 	sc->sc_dev = dev;
358 
359 	PWM_LOCK_INIT(sc);
360 
361 	sc->sc_mem_res = bus_alloc_resource_any(dev, SYS_RES_MEMORY,
362 	    &sc->sc_mem_rid, RF_ACTIVE);
363 	if (sc->sc_mem_res == NULL) {
364 		device_printf(dev, "cannot allocate memory resources\n");
365 		goto fail;
366 	}
367 
368 	/* Init backlight interface */
369 	ctx = device_get_sysctl_ctx(sc->sc_dev);
370 	tree = device_get_sysctl_tree(sc->sc_dev);
371 
372 	sc->sc_clkdiv_oid = SYSCTL_ADD_PROC(ctx, SYSCTL_CHILDREN(tree), OID_AUTO,
373 	    "clkdiv", CTLTYPE_INT | CTLFLAG_RW, sc, 0,
374 	    am335x_ehrpwm_sysctl_clkdiv, "I", "PWM clock prescaler");
375 
376 	sc->sc_freq_oid = SYSCTL_ADD_PROC(ctx, SYSCTL_CHILDREN(tree), OID_AUTO,
377 	    "freq", CTLTYPE_INT | CTLFLAG_RW, sc, 0,
378 	    am335x_ehrpwm_sysctl_freq, "I", "PWM frequency");
379 
380 	sc->sc_period_oid = SYSCTL_ADD_PROC(ctx, SYSCTL_CHILDREN(tree), OID_AUTO,
381 	    "period", CTLTYPE_INT | CTLFLAG_RW, sc, 0,
382 	    am335x_ehrpwm_sysctl_period, "I", "PWM period");
383 
384 	sc->sc_chanA_oid = SYSCTL_ADD_PROC(ctx, SYSCTL_CHILDREN(tree), OID_AUTO,
385 	    "dutyA", CTLTYPE_INT | CTLFLAG_RW, sc, 0,
386 	    am335x_ehrpwm_sysctl_duty, "I", "Channel A duty cycles");
387 
388 	sc->sc_chanB_oid = SYSCTL_ADD_PROC(ctx, SYSCTL_CHILDREN(tree), OID_AUTO,
389 	    "dutyB", CTLTYPE_INT | CTLFLAG_RW, sc, 0,
390 	    am335x_ehrpwm_sysctl_duty, "I", "Channel B duty cycles");
391 
392 	/* CONFIGURE EPWM1 */
393 	reg = EPWM_READ2(sc, EPWM_TBCTL);
394 	reg &= ~(TBCTL_CLKDIV_MASK | TBCTL_HSPCLKDIV_MASK);
395 	EPWM_WRITE2(sc, EPWM_TBCTL, reg);
396 
397 	sc->sc_pwm_period = DEFAULT_PWM_PERIOD;
398 	sc->sc_pwm_dutyA = 0;
399 	sc->sc_pwm_dutyB = 0;
400 	am335x_ehrpwm_freq(sc);
401 
402 	EPWM_WRITE2(sc, EPWM_TBPRD, sc->sc_pwm_period - 1);
403 	EPWM_WRITE2(sc, EPWM_CMPA, sc->sc_pwm_dutyA);
404 	EPWM_WRITE2(sc, EPWM_CMPB, sc->sc_pwm_dutyB);
405 
406 	EPWM_WRITE2(sc, EPWM_AQCTLA, (AQCTL_ZRO_SET | AQCTL_CAU_CLEAR));
407 	EPWM_WRITE2(sc, EPWM_AQCTLB, (AQCTL_ZRO_SET | AQCTL_CBU_CLEAR));
408 
409 	/* START EPWM */
410 	reg &= ~TBCTL_CTRMODE_MASK;
411 	reg |= TBCTL_CTRMODE_UP | TBCTL_FREERUN;
412 	EPWM_WRITE2(sc, EPWM_TBCTL, reg);
413 
414 	EPWM_WRITE2(sc, EPWM_TZCTL, 0xf);
415 	reg = EPWM_READ2(sc, EPWM_TZFLG);
416 
417 	return (0);
418 fail:
419 	PWM_LOCK_DESTROY(sc);
420 	if (sc->sc_mem_res)
421 		bus_release_resource(dev, SYS_RES_MEMORY,
422 		    sc->sc_mem_rid, sc->sc_mem_res);
423 
424 	return(ENXIO);
425 }
426 
427 static int
428 am335x_ehrpwm_detach(device_t dev)
429 {
430 	struct am335x_ehrpwm_softc *sc;
431 
432 	sc = device_get_softc(dev);
433 
434 	PWM_LOCK(sc);
435 	if (sc->sc_mem_res)
436 		bus_release_resource(dev, SYS_RES_MEMORY,
437 		    sc->sc_mem_rid, sc->sc_mem_res);
438 	PWM_UNLOCK(sc);
439 
440 	PWM_LOCK_DESTROY(sc);
441 
442 	return (0);
443 }
444 
445 DRIVER_MODULE(am335x_ehrpwm, am335x_pwmss, am335x_ehrpwm_driver, am335x_ehrpwm_devclass, 0, 0);
446 MODULE_VERSION(am335x_ehrpwm, 1);
447 MODULE_DEPEND(am335x_ehrpwm, am335x_pwmss, 1, 1, 1);
448