xref: /freebsd/sys/arm/xilinx/zy7_gpio.c (revision ff0ba87247820afbdfdc1b307c803f7923d0e4d3)
1 /*-
2  * Copyright (c) 2013 Thomas Skibo
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  * $FreeBSD$
27  */
28 
29 /*
30  * A GPIO driver for Xilinx Zynq-7000.
31  *
32  * The GPIO peripheral on Zynq allows controlling 114 general purpose I/Os.
33  *
34  * Pins 53-0 are sent to the MIO.  Any MIO pins not used by a PS peripheral are
35  * available as a GPIO pin.  Pins 64-127 are sent to the PL (FPGA) section of
36  * Zynq as EMIO signals.
37  *
38  * The hardware provides a way to use IOs as interrupt sources but the
39  * gpio framework doesn't seem to have hooks for this.
40  *
41  * Reference: Zynq-7000 All Programmable SoC Technical Reference Manual.
42  * (v1.4) November 16, 2012.  Xilinx doc UG585.  GPIO is covered in
43  * chater 14.  Register definitions are in appendix B.19.
44  */
45 
46 #include <sys/cdefs.h>
47 __FBSDID("$FreeBSD$");
48 
49 #include <sys/param.h>
50 #include <sys/systm.h>
51 #include <sys/conf.h>
52 #include <sys/bus.h>
53 #include <sys/kernel.h>
54 #include <sys/module.h>
55 #include <sys/lock.h>
56 #include <sys/mutex.h>
57 #include <sys/resource.h>
58 #include <sys/rman.h>
59 #include <sys/gpio.h>
60 
61 #include <machine/bus.h>
62 #include <machine/resource.h>
63 #include <machine/stdarg.h>
64 
65 #include <dev/fdt/fdt_common.h>
66 #include <dev/ofw/ofw_bus.h>
67 #include <dev/ofw/ofw_bus_subr.h>
68 
69 #include "gpio_if.h"
70 
71 #define NUMBANKS	4
72 #define MAXPIN		(32*NUMBANKS)
73 
74 #define MIO_PIN		0	/* pins 0-53 go to MIO */
75 #define NUM_MIO_PINS	54
76 #define EMIO_PIN	64	/* pins 64-127 go to PL */
77 #define NUM_EMIO_PINS	64
78 
79 #define VALID_PIN(u)	(((u) >= MIO_PIN && (u) < MIO_PIN + NUM_MIO_PINS) || \
80 			 ((u) >= EMIO_PIN && (u) < EMIO_PIN + NUM_EMIO_PINS))
81 
82 #define ZGPIO_LOCK(sc)			mtx_lock(&(sc)->sc_mtx)
83 #define	ZGPIO_UNLOCK(sc)		mtx_unlock(&(sc)->sc_mtx)
84 #define ZGPIO_LOCK_INIT(sc) \
85 	mtx_init(&(sc)->sc_mtx, device_get_nameunit((sc)->dev),	\
86 	    "gpio", MTX_DEF)
87 #define ZGPIO_LOCK_DESTROY(_sc)	mtx_destroy(&_sc->sc_mtx);
88 
89 struct zy7_gpio_softc {
90 	device_t	dev;
91 	struct mtx	sc_mtx;
92 	struct resource *mem_res;	/* Memory resource */
93 };
94 
95 #define WR4(sc, off, val)	bus_write_4((sc)->mem_res, (off), (val))
96 #define RD4(sc, off)		bus_read_4((sc)->mem_res, (off))
97 
98 
99 /* Xilinx Zynq-7000 GPIO register definitions:
100  */
101 #define ZY7_GPIO_MASK_DATA_LSW(b)	(0x0000+8*(b))	/* maskable wr lo */
102 #define ZY7_GPIO_MASK_DATA_MSW(b)	(0x0004+8*(b))	/* maskable wr hi */
103 #define ZY7_GPIO_DATA(b)		(0x0040+4*(b))	/* in/out data */
104 #define ZY7_GPIO_DATA_RO(b)		(0x0060+4*(b))	/* input data */
105 
106 #define ZY7_GPIO_DIRM(b)		(0x0204+0x40*(b)) /* direction mode */
107 #define ZY7_GPIO_OEN(b)			(0x0208+0x40*(b)) /* output enable */
108 #define ZY7_GPIO_INT_MASK(b)		(0x020c+0x40*(b)) /* int mask */
109 #define ZY7_GPIO_INT_EN(b)		(0x0210+0x40*(b)) /* int enable */
110 #define ZY7_GPIO_INT_DIS(b)		(0x0214+0x40*(b)) /* int disable */
111 #define ZY7_GPIO_INT_STAT(b)		(0x0218+0x40*(b)) /* int status */
112 #define ZY7_GPIO_INT_TYPE(b)		(0x021c+0x40*(b)) /* int type */
113 #define ZY7_GPIO_INT_POLARITY(b)	(0x0220+0x40*(b)) /* int polarity */
114 #define ZY7_GPIO_INT_ANY(b)		(0x0224+0x40*(b)) /* any edge */
115 
116 
117 static int
118 zy7_gpio_pin_max(device_t dev, int *maxpin)
119 {
120 
121 	*maxpin = MAXPIN;
122 	return (0);
123 }
124 
125 /* Get a specific pin's capabilities. */
126 static int
127 zy7_gpio_pin_getcaps(device_t dev, uint32_t pin, uint32_t *caps)
128 {
129 
130 	if (!VALID_PIN(pin))
131 		return (EINVAL);
132 
133 	*caps = (GPIO_PIN_INPUT | GPIO_PIN_OUTPUT | GPIO_PIN_TRISTATE);
134 
135 	return (0);
136 }
137 
138 /* Get a specific pin's name. */
139 static int
140 zy7_gpio_pin_getname(device_t dev, uint32_t pin, char *name)
141 {
142 
143 	if (!VALID_PIN(pin))
144 		return (EINVAL);
145 
146 	if (pin < NUM_MIO_PINS) {
147 		snprintf(name, GPIOMAXNAME, "MIO_%d", pin);
148 		name[GPIOMAXNAME - 1] = '\0';
149 	} else {
150 		snprintf(name, GPIOMAXNAME, "EMIO_%d", pin - EMIO_PIN);
151 		name[GPIOMAXNAME - 1] = '\0';
152 	}
153 
154 	return (0);
155 }
156 
157 /* Get a specific pin's current in/out/tri state. */
158 static int
159 zy7_gpio_pin_getflags(device_t dev, uint32_t pin, uint32_t *flags)
160 {
161 	struct zy7_gpio_softc *sc = device_get_softc(dev);
162 
163 	if (!VALID_PIN(pin))
164 		return (EINVAL);
165 
166 	ZGPIO_LOCK(sc);
167 
168 	if ((RD4(sc, ZY7_GPIO_DIRM(pin >> 5)) & (1 << (pin & 31))) != 0) {
169 		/* output */
170 		if ((RD4(sc, ZY7_GPIO_OEN(pin >> 5)) & (1 << (pin & 31))) == 0)
171 			*flags = (GPIO_PIN_OUTPUT | GPIO_PIN_TRISTATE);
172 		else
173 			*flags = GPIO_PIN_OUTPUT;
174 	} else
175 		/* input */
176 		*flags = GPIO_PIN_INPUT;
177 
178 	ZGPIO_UNLOCK(sc);
179 
180 	return (0);
181 }
182 
183 /* Set a specific pin's in/out/tri state. */
184 static int
185 zy7_gpio_pin_setflags(device_t dev, uint32_t pin, uint32_t flags)
186 {
187 	struct zy7_gpio_softc *sc = device_get_softc(dev);
188 
189 	if (!VALID_PIN(pin))
190 		return (EINVAL);
191 
192 	ZGPIO_LOCK(sc);
193 
194 	if ((flags & GPIO_PIN_OUTPUT) != 0) {
195 		/* Output.  Set or reset OEN too. */
196 		WR4(sc, ZY7_GPIO_DIRM(pin >> 5),
197 		    RD4(sc, ZY7_GPIO_DIRM(pin >> 5)) | (1 << (pin & 31)));
198 
199 		if ((flags & GPIO_PIN_TRISTATE) != 0)
200 			WR4(sc, ZY7_GPIO_OEN(pin >> 5),
201 			    RD4(sc, ZY7_GPIO_OEN(pin >> 5)) &
202 			    ~(1 << (pin & 31)));
203 		else
204 			WR4(sc, ZY7_GPIO_OEN(pin >> 5),
205 			    RD4(sc, ZY7_GPIO_OEN(pin >> 5)) |
206 			    (1 << (pin & 31)));
207 	} else {
208 		/* Input.  Turn off OEN. */
209 		WR4(sc, ZY7_GPIO_DIRM(pin >> 5),
210 		    RD4(sc, ZY7_GPIO_DIRM(pin >> 5)) & ~(1 << (pin & 31)));
211 		WR4(sc, ZY7_GPIO_OEN(pin >> 5),
212 		    RD4(sc, ZY7_GPIO_OEN(pin >> 5)) & ~(1 << (pin & 31)));
213 	}
214 
215 	ZGPIO_UNLOCK(sc);
216 
217 	return (0);
218 }
219 
220 /* Set a specific output pin's value. */
221 static int
222 zy7_gpio_pin_set(device_t dev, uint32_t pin, unsigned int value)
223 {
224 	struct zy7_gpio_softc *sc = device_get_softc(dev);
225 
226 	if (!VALID_PIN(pin) || value > 1)
227 		return (EINVAL);
228 
229 	/* Fancy register tricks allow atomic set or reset. */
230 	if ((pin & 16) != 0)
231 		WR4(sc, ZY7_GPIO_MASK_DATA_MSW(pin >> 5),
232 		    (0xffff0000 ^ (0x10000 << (pin & 15))) |
233 		    (value << (pin & 15)));
234 	else
235 		WR4(sc, ZY7_GPIO_MASK_DATA_LSW(pin >> 5),
236 		    (0xffff0000 ^ (0x10000 << (pin & 15))) |
237 		    (value << (pin & 15)));
238 
239 	return (0);
240 }
241 
242 /* Get a specific pin's input value. */
243 static int
244 zy7_gpio_pin_get(device_t dev, uint32_t pin, unsigned int *value)
245 {
246 	struct zy7_gpio_softc *sc = device_get_softc(dev);
247 
248 	if (!VALID_PIN(pin))
249 		return (EINVAL);
250 
251 	*value = (RD4(sc, ZY7_GPIO_DATA_RO(pin >> 5)) >> (pin & 31)) & 1;
252 
253 	return (0);
254 }
255 
256 /* Toggle a pin's output value. */
257 static int
258 zy7_gpio_pin_toggle(device_t dev, uint32_t pin)
259 {
260 	struct zy7_gpio_softc *sc = device_get_softc(dev);
261 
262 	if (!VALID_PIN(pin))
263 		return (EINVAL);
264 
265 	ZGPIO_LOCK(sc);
266 
267 	WR4(sc, ZY7_GPIO_DATA(pin >> 5),
268 	    RD4(sc, ZY7_GPIO_DATA(pin >> 5)) ^ (1 << (pin & 31)));
269 
270 	ZGPIO_UNLOCK(sc);
271 
272 	return (0);
273 }
274 
275 static int
276 zy7_gpio_probe(device_t dev)
277 {
278 
279 	if (!ofw_bus_status_okay(dev))
280 		return (ENXIO);
281 
282 	if (!ofw_bus_is_compatible(dev, "xlnx,zy7_gpio"))
283 		return (ENXIO);
284 
285 	device_set_desc(dev, "Zynq-7000 GPIO driver");
286 	return (0);
287 }
288 
289 static void
290 zy7_gpio_hw_reset(struct zy7_gpio_softc *sc)
291 {
292 	int i;
293 
294 	for (i = 0; i < NUMBANKS; i++) {
295 		WR4(sc, ZY7_GPIO_DATA(i), 0);
296 		WR4(sc, ZY7_GPIO_DIRM(i), 0);
297 		WR4(sc, ZY7_GPIO_OEN(i), 0);
298 		WR4(sc, ZY7_GPIO_INT_DIS(i), 0xffffffff);
299 		WR4(sc, ZY7_GPIO_INT_POLARITY(i), 0);
300 		WR4(sc, ZY7_GPIO_INT_TYPE(i),
301 		    i == 1 ? 0x003fffff : 0xffffffff);
302 		WR4(sc, ZY7_GPIO_INT_ANY(i), 0);
303 		WR4(sc, ZY7_GPIO_INT_STAT(i), 0xffffffff);
304 	}
305 }
306 
307 static int zy7_gpio_detach(device_t dev);
308 
309 static int
310 zy7_gpio_attach(device_t dev)
311 {
312 	struct zy7_gpio_softc *sc = device_get_softc(dev);
313 	int rid;
314 
315 	sc->dev = dev;
316 
317 	ZGPIO_LOCK_INIT(sc);
318 
319 	/* Allocate memory. */
320 	rid = 0;
321 	sc->mem_res = bus_alloc_resource_any(dev,
322 		     SYS_RES_MEMORY, &rid, RF_ACTIVE);
323 	if (sc->mem_res == NULL) {
324 		device_printf(dev, "Can't allocate memory for device");
325 		zy7_gpio_detach(dev);
326 		return (ENOMEM);
327 	}
328 
329 	/* Completely reset. */
330 	zy7_gpio_hw_reset(sc);
331 
332 	device_add_child(dev, "gpioc", -1);
333 	device_add_child(dev, "gpiobus", -1);
334 
335 	return (bus_generic_attach(dev));
336 }
337 
338 static int
339 zy7_gpio_detach(device_t dev)
340 {
341 	struct zy7_gpio_softc *sc = device_get_softc(dev);
342 
343 	bus_generic_detach(dev);
344 
345 	if (sc->mem_res != NULL) {
346 		/* Release memory resource. */
347 		bus_release_resource(dev, SYS_RES_MEMORY,
348 				     rman_get_rid(sc->mem_res), sc->mem_res);
349 	}
350 
351 	ZGPIO_LOCK_DESTROY(sc);
352 
353 	return (0);
354 }
355 
356 static device_method_t zy7_gpio_methods[] = {
357 	/* device_if */
358 	DEVMETHOD(device_probe, 	zy7_gpio_probe),
359 	DEVMETHOD(device_attach, 	zy7_gpio_attach),
360 	DEVMETHOD(device_detach, 	zy7_gpio_detach),
361 
362 	/* GPIO protocol */
363 	DEVMETHOD(gpio_pin_max, 	zy7_gpio_pin_max),
364 	DEVMETHOD(gpio_pin_getname, 	zy7_gpio_pin_getname),
365 	DEVMETHOD(gpio_pin_getflags, 	zy7_gpio_pin_getflags),
366 	DEVMETHOD(gpio_pin_getcaps, 	zy7_gpio_pin_getcaps),
367 	DEVMETHOD(gpio_pin_setflags, 	zy7_gpio_pin_setflags),
368 	DEVMETHOD(gpio_pin_get, 	zy7_gpio_pin_get),
369 	DEVMETHOD(gpio_pin_set, 	zy7_gpio_pin_set),
370 	DEVMETHOD(gpio_pin_toggle, 	zy7_gpio_pin_toggle),
371 
372 	DEVMETHOD_END
373 };
374 
375 static driver_t zy7_gpio_driver = {
376 	"zy7_gpio",
377 	zy7_gpio_methods,
378 	sizeof(struct zy7_gpio_softc),
379 };
380 static devclass_t zy7_gpio_devclass;
381 
382 extern devclass_t gpiobus_devclass, gpioc_devclass;
383 extern driver_t gpiobus_driver, gpioc_driver;
384 
385 DRIVER_MODULE(zy7_gpio, simplebus, zy7_gpio_driver, zy7_gpio_devclass, \
386 	      NULL, NULL);
387 DRIVER_MODULE(gpiobus, zy7_gpio, gpiobus_driver, gpiobus_devclass, 0, 0);
388 DRIVER_MODULE(gpioc, zy7_gpio, gpioc_driver, gpioc_devclass, 0, 0);
389