xref: /freebsd/sys/arm/xilinx/zy7_gpio.c (revision ba3c1f5972d7b90feb6e6da47905ff2757e0fe57)
1 /*-
2  * SPDX-License-Identifier: BSD-2-Clause
3  *
4  * Copyright (c) 2013 Thomas Skibo
5  * All rights reserved.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  * 1. Redistributions of source code must retain the above copyright
11  *    notice, this list of conditions and the following disclaimer.
12  * 2. Redistributions in binary form must reproduce the above copyright
13  *    notice, this list of conditions and the following disclaimer in the
14  *    documentation and/or other materials provided with the distribution.
15  *
16  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
17  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
18  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
19  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
20  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
21  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
22  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
23  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
24  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
25  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
26  * SUCH DAMAGE.
27  *
28  * $FreeBSD$
29  */
30 
31 /*
32  * A GPIO driver for Xilinx Zynq-7000.
33  *
34  * The GPIO peripheral on Zynq allows controlling 114 general purpose I/Os.
35  *
36  * Pins 53-0 are sent to the MIO.  Any MIO pins not used by a PS peripheral are
37  * available as a GPIO pin.  Pins 64-127 are sent to the PL (FPGA) section of
38  * Zynq as EMIO signals.
39  *
40  * The hardware provides a way to use IOs as interrupt sources but the
41  * gpio framework doesn't seem to have hooks for this.
42  *
43  * Reference: Zynq-7000 All Programmable SoC Technical Reference Manual.
44  * (v1.4) November 16, 2012.  Xilinx doc UG585.  GPIO is covered in
45  * chater 14.  Register definitions are in appendix B.19.
46  */
47 
48 #include <sys/cdefs.h>
49 __FBSDID("$FreeBSD$");
50 
51 #include <sys/param.h>
52 #include <sys/systm.h>
53 #include <sys/conf.h>
54 #include <sys/bus.h>
55 #include <sys/kernel.h>
56 #include <sys/module.h>
57 #include <sys/lock.h>
58 #include <sys/mutex.h>
59 #include <sys/resource.h>
60 #include <sys/rman.h>
61 #include <sys/gpio.h>
62 
63 #include <machine/bus.h>
64 #include <machine/resource.h>
65 #include <machine/stdarg.h>
66 
67 #include <dev/gpio/gpiobusvar.h>
68 #include <dev/ofw/ofw_bus.h>
69 #include <dev/ofw/ofw_bus_subr.h>
70 
71 #include "gpio_if.h"
72 
73 #define NUMBANKS	4
74 #define MAXPIN		(32*NUMBANKS)
75 
76 #define MIO_PIN		0	/* pins 0-53 go to MIO */
77 #define NUM_MIO_PINS	54
78 #define EMIO_PIN	64	/* pins 64-127 go to PL */
79 #define NUM_EMIO_PINS	64
80 
81 #define VALID_PIN(u)	(((u) >= MIO_PIN && (u) < MIO_PIN + NUM_MIO_PINS) || \
82 			 ((u) >= EMIO_PIN && (u) < EMIO_PIN + NUM_EMIO_PINS))
83 
84 #define ZGPIO_LOCK(sc)			mtx_lock(&(sc)->sc_mtx)
85 #define	ZGPIO_UNLOCK(sc)		mtx_unlock(&(sc)->sc_mtx)
86 #define ZGPIO_LOCK_INIT(sc) \
87 	mtx_init(&(sc)->sc_mtx, device_get_nameunit((sc)->dev),	\
88 	    "gpio", MTX_DEF)
89 #define ZGPIO_LOCK_DESTROY(_sc)	mtx_destroy(&_sc->sc_mtx);
90 
91 struct zy7_gpio_softc {
92 	device_t	dev;
93 	device_t	busdev;
94 	struct mtx	sc_mtx;
95 	struct resource *mem_res;	/* Memory resource */
96 };
97 
98 #define WR4(sc, off, val)	bus_write_4((sc)->mem_res, (off), (val))
99 #define RD4(sc, off)		bus_read_4((sc)->mem_res, (off))
100 
101 /* Xilinx Zynq-7000 GPIO register definitions:
102  */
103 #define ZY7_GPIO_MASK_DATA_LSW(b)	(0x0000+8*(b))	/* maskable wr lo */
104 #define ZY7_GPIO_MASK_DATA_MSW(b)	(0x0004+8*(b))	/* maskable wr hi */
105 #define ZY7_GPIO_DATA(b)		(0x0040+4*(b))	/* in/out data */
106 #define ZY7_GPIO_DATA_RO(b)		(0x0060+4*(b))	/* input data */
107 
108 #define ZY7_GPIO_DIRM(b)		(0x0204+0x40*(b)) /* direction mode */
109 #define ZY7_GPIO_OEN(b)			(0x0208+0x40*(b)) /* output enable */
110 #define ZY7_GPIO_INT_MASK(b)		(0x020c+0x40*(b)) /* int mask */
111 #define ZY7_GPIO_INT_EN(b)		(0x0210+0x40*(b)) /* int enable */
112 #define ZY7_GPIO_INT_DIS(b)		(0x0214+0x40*(b)) /* int disable */
113 #define ZY7_GPIO_INT_STAT(b)		(0x0218+0x40*(b)) /* int status */
114 #define ZY7_GPIO_INT_TYPE(b)		(0x021c+0x40*(b)) /* int type */
115 #define ZY7_GPIO_INT_POLARITY(b)	(0x0220+0x40*(b)) /* int polarity */
116 #define ZY7_GPIO_INT_ANY(b)		(0x0224+0x40*(b)) /* any edge */
117 
118 static device_t
119 zy7_gpio_get_bus(device_t dev)
120 {
121 	struct zy7_gpio_softc *sc;
122 
123 	sc = device_get_softc(dev);
124 
125 	return (sc->busdev);
126 }
127 
128 static int
129 zy7_gpio_pin_max(device_t dev, int *maxpin)
130 {
131 
132 	*maxpin = MAXPIN;
133 	return (0);
134 }
135 
136 /* Get a specific pin's capabilities. */
137 static int
138 zy7_gpio_pin_getcaps(device_t dev, uint32_t pin, uint32_t *caps)
139 {
140 
141 	if (!VALID_PIN(pin))
142 		return (EINVAL);
143 
144 	*caps = (GPIO_PIN_INPUT | GPIO_PIN_OUTPUT | GPIO_PIN_TRISTATE);
145 
146 	return (0);
147 }
148 
149 /* Get a specific pin's name. */
150 static int
151 zy7_gpio_pin_getname(device_t dev, uint32_t pin, char *name)
152 {
153 
154 	if (!VALID_PIN(pin))
155 		return (EINVAL);
156 
157 	if (pin < NUM_MIO_PINS) {
158 		snprintf(name, GPIOMAXNAME, "MIO_%d", pin);
159 		name[GPIOMAXNAME - 1] = '\0';
160 	} else {
161 		snprintf(name, GPIOMAXNAME, "EMIO_%d", pin - EMIO_PIN);
162 		name[GPIOMAXNAME - 1] = '\0';
163 	}
164 
165 	return (0);
166 }
167 
168 /* Get a specific pin's current in/out/tri state. */
169 static int
170 zy7_gpio_pin_getflags(device_t dev, uint32_t pin, uint32_t *flags)
171 {
172 	struct zy7_gpio_softc *sc = device_get_softc(dev);
173 
174 	if (!VALID_PIN(pin))
175 		return (EINVAL);
176 
177 	ZGPIO_LOCK(sc);
178 
179 	if ((RD4(sc, ZY7_GPIO_DIRM(pin >> 5)) & (1 << (pin & 31))) != 0) {
180 		/* output */
181 		if ((RD4(sc, ZY7_GPIO_OEN(pin >> 5)) & (1 << (pin & 31))) == 0)
182 			*flags = (GPIO_PIN_OUTPUT | GPIO_PIN_TRISTATE);
183 		else
184 			*flags = GPIO_PIN_OUTPUT;
185 	} else
186 		/* input */
187 		*flags = GPIO_PIN_INPUT;
188 
189 	ZGPIO_UNLOCK(sc);
190 
191 	return (0);
192 }
193 
194 /* Set a specific pin's in/out/tri state. */
195 static int
196 zy7_gpio_pin_setflags(device_t dev, uint32_t pin, uint32_t flags)
197 {
198 	struct zy7_gpio_softc *sc = device_get_softc(dev);
199 
200 	if (!VALID_PIN(pin))
201 		return (EINVAL);
202 
203 	ZGPIO_LOCK(sc);
204 
205 	if ((flags & GPIO_PIN_OUTPUT) != 0) {
206 		/* Output.  Set or reset OEN too. */
207 		WR4(sc, ZY7_GPIO_DIRM(pin >> 5),
208 		    RD4(sc, ZY7_GPIO_DIRM(pin >> 5)) | (1 << (pin & 31)));
209 
210 		if ((flags & GPIO_PIN_TRISTATE) != 0)
211 			WR4(sc, ZY7_GPIO_OEN(pin >> 5),
212 			    RD4(sc, ZY7_GPIO_OEN(pin >> 5)) &
213 			    ~(1 << (pin & 31)));
214 		else
215 			WR4(sc, ZY7_GPIO_OEN(pin >> 5),
216 			    RD4(sc, ZY7_GPIO_OEN(pin >> 5)) |
217 			    (1 << (pin & 31)));
218 	} else {
219 		/* Input.  Turn off OEN. */
220 		WR4(sc, ZY7_GPIO_DIRM(pin >> 5),
221 		    RD4(sc, ZY7_GPIO_DIRM(pin >> 5)) & ~(1 << (pin & 31)));
222 		WR4(sc, ZY7_GPIO_OEN(pin >> 5),
223 		    RD4(sc, ZY7_GPIO_OEN(pin >> 5)) & ~(1 << (pin & 31)));
224 	}
225 
226 	ZGPIO_UNLOCK(sc);
227 
228 	return (0);
229 }
230 
231 /* Set a specific output pin's value. */
232 static int
233 zy7_gpio_pin_set(device_t dev, uint32_t pin, unsigned int value)
234 {
235 	struct zy7_gpio_softc *sc = device_get_softc(dev);
236 
237 	if (!VALID_PIN(pin) || value > 1)
238 		return (EINVAL);
239 
240 	/* Fancy register tricks allow atomic set or reset. */
241 	if ((pin & 16) != 0)
242 		WR4(sc, ZY7_GPIO_MASK_DATA_MSW(pin >> 5),
243 		    (0xffff0000 ^ (0x10000 << (pin & 15))) |
244 		    (value << (pin & 15)));
245 	else
246 		WR4(sc, ZY7_GPIO_MASK_DATA_LSW(pin >> 5),
247 		    (0xffff0000 ^ (0x10000 << (pin & 15))) |
248 		    (value << (pin & 15)));
249 
250 	return (0);
251 }
252 
253 /* Get a specific pin's input value. */
254 static int
255 zy7_gpio_pin_get(device_t dev, uint32_t pin, unsigned int *value)
256 {
257 	struct zy7_gpio_softc *sc = device_get_softc(dev);
258 
259 	if (!VALID_PIN(pin))
260 		return (EINVAL);
261 
262 	*value = (RD4(sc, ZY7_GPIO_DATA_RO(pin >> 5)) >> (pin & 31)) & 1;
263 
264 	return (0);
265 }
266 
267 /* Toggle a pin's output value. */
268 static int
269 zy7_gpio_pin_toggle(device_t dev, uint32_t pin)
270 {
271 	struct zy7_gpio_softc *sc = device_get_softc(dev);
272 
273 	if (!VALID_PIN(pin))
274 		return (EINVAL);
275 
276 	ZGPIO_LOCK(sc);
277 
278 	WR4(sc, ZY7_GPIO_DATA(pin >> 5),
279 	    RD4(sc, ZY7_GPIO_DATA(pin >> 5)) ^ (1 << (pin & 31)));
280 
281 	ZGPIO_UNLOCK(sc);
282 
283 	return (0);
284 }
285 
286 static int
287 zy7_gpio_probe(device_t dev)
288 {
289 
290 	if (!ofw_bus_status_okay(dev))
291 		return (ENXIO);
292 
293 	if (!ofw_bus_is_compatible(dev, "xlnx,zy7_gpio"))
294 		return (ENXIO);
295 
296 	device_set_desc(dev, "Zynq-7000 GPIO driver");
297 	return (0);
298 }
299 
300 static int zy7_gpio_detach(device_t dev);
301 
302 static int
303 zy7_gpio_attach(device_t dev)
304 {
305 	struct zy7_gpio_softc *sc = device_get_softc(dev);
306 	int rid;
307 
308 	sc->dev = dev;
309 
310 	ZGPIO_LOCK_INIT(sc);
311 
312 	/* Allocate memory. */
313 	rid = 0;
314 	sc->mem_res = bus_alloc_resource_any(dev,
315 		     SYS_RES_MEMORY, &rid, RF_ACTIVE);
316 	if (sc->mem_res == NULL) {
317 		device_printf(dev, "Can't allocate memory for device");
318 		zy7_gpio_detach(dev);
319 		return (ENOMEM);
320 	}
321 
322 	sc->busdev = gpiobus_attach_bus(dev);
323 	if (sc->busdev == NULL) {
324 		zy7_gpio_detach(dev);
325 		return (ENOMEM);
326 	}
327 
328 	return (0);
329 }
330 
331 static int
332 zy7_gpio_detach(device_t dev)
333 {
334 	struct zy7_gpio_softc *sc = device_get_softc(dev);
335 
336 	gpiobus_detach_bus(dev);
337 
338 	if (sc->mem_res != NULL) {
339 		/* Release memory resource. */
340 		bus_release_resource(dev, SYS_RES_MEMORY,
341 				     rman_get_rid(sc->mem_res), sc->mem_res);
342 	}
343 
344 	ZGPIO_LOCK_DESTROY(sc);
345 
346 	return (0);
347 }
348 
349 static device_method_t zy7_gpio_methods[] = {
350 	/* device_if */
351 	DEVMETHOD(device_probe, 	zy7_gpio_probe),
352 	DEVMETHOD(device_attach, 	zy7_gpio_attach),
353 	DEVMETHOD(device_detach, 	zy7_gpio_detach),
354 
355 	/* GPIO protocol */
356 	DEVMETHOD(gpio_get_bus, 	zy7_gpio_get_bus),
357 	DEVMETHOD(gpio_pin_max, 	zy7_gpio_pin_max),
358 	DEVMETHOD(gpio_pin_getname, 	zy7_gpio_pin_getname),
359 	DEVMETHOD(gpio_pin_getflags, 	zy7_gpio_pin_getflags),
360 	DEVMETHOD(gpio_pin_getcaps, 	zy7_gpio_pin_getcaps),
361 	DEVMETHOD(gpio_pin_setflags, 	zy7_gpio_pin_setflags),
362 	DEVMETHOD(gpio_pin_get, 	zy7_gpio_pin_get),
363 	DEVMETHOD(gpio_pin_set, 	zy7_gpio_pin_set),
364 	DEVMETHOD(gpio_pin_toggle, 	zy7_gpio_pin_toggle),
365 
366 	DEVMETHOD_END
367 };
368 
369 static driver_t zy7_gpio_driver = {
370 	"gpio",
371 	zy7_gpio_methods,
372 	sizeof(struct zy7_gpio_softc),
373 };
374 
375 DRIVER_MODULE(zy7_gpio, simplebus, zy7_gpio_driver, NULL, NULL);
376