xref: /freebsd/sys/arm/freescale/imx/imx_iomux.c (revision efe3b0de1438e7a8473d92f2be57072394559e3c)
1 /*-
2  * Copyright (c) 2014 Ian Lepore
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  * Pin mux and pad control driver for imx5 and imx6.
31  *
32  * This driver implements the fdt_pinctrl interface for configuring the gpio and
33  * peripheral pins based on fdt configuration data.
34  *
35  * When the driver attaches, it walks the entire fdt tree and automatically
36  * configures the pins for each device which has a pinctrl-0 property and whose
37  * status is "okay".  In addition it implements the fdt_pinctrl_configure()
38  * method which any other driver can call at any time to reconfigure its pins.
39  *
40  * The nature of the fsl,pins property in fdt data makes this driver's job very
41  * easy.  Instead of representing each pin and pad configuration using symbolic
42  * properties such as pullup-enable="true" and so on, the data simply contains
43  * the addresses of the registers that control the pins, and the raw values to
44  * store in those registers.
45  *
46  * The imx5 and imx6 SoCs also have a small number of "general purpose
47  * registers" in the iomuxc device which are used to control an assortment
48  * of completely unrelated aspects of SoC behavior.  This driver provides other
49  * drivers with direct access to those registers via simple accessor functions.
50  */
51 
52 #include <sys/param.h>
53 #include <sys/systm.h>
54 #include <sys/bus.h>
55 #include <sys/kernel.h>
56 #include <sys/module.h>
57 #include <sys/malloc.h>
58 #include <sys/rman.h>
59 
60 #include <machine/bus.h>
61 
62 #include <dev/ofw/openfirm.h>
63 #include <dev/ofw/ofw_bus.h>
64 #include <dev/ofw/ofw_bus_subr.h>
65 #include <dev/fdt/fdt_pinctrl.h>
66 
67 #include <arm/freescale/imx/imx_iomuxvar.h>
68 #include <arm/freescale/imx/imx_machdep.h>
69 
70 struct iomux_softc {
71 	device_t	dev;
72 	struct resource	*mem_res;
73 	u_int		last_gpreg;
74 };
75 
76 static struct iomux_softc *iomux_sc;
77 
78 static struct ofw_compat_data compat_data[] = {
79 	{"fsl,imx6dl-iomuxc",	true},
80 	{"fsl,imx6q-iomuxc",	true},
81 	{"fsl,imx6sl-iomuxc",	true},
82 	{"fsl,imx6sx-iomuxc",	true},
83 	{"fsl,imx53-iomuxc",	true},
84 	{"fsl,imx51-iomuxc",	true},
85 	{NULL,			false},
86 };
87 
88 /*
89  * Each tuple in an fsl,pins property contains these fields.
90  */
91 struct pincfg {
92 	uint32_t mux_reg;
93 	uint32_t padconf_reg;
94 	uint32_t input_reg;
95 	uint32_t mux_val;
96 	uint32_t input_val;
97 	uint32_t padconf_val;
98 };
99 
100 #define	PADCONF_NONE	(1U << 31)	/* Do not configure pad. */
101 #define	PADCONF_SION	(1U << 30)	/* Force SION bit in mux register. */
102 #define	PADMUX_SION	(1U <<  4)	/* The SION bit in the mux register. */
103 
104 static inline uint32_t
105 RD4(struct iomux_softc *sc, bus_size_t off)
106 {
107 
108 	return (bus_read_4(sc->mem_res, off));
109 }
110 
111 static inline void
112 WR4(struct iomux_softc *sc, bus_size_t off, uint32_t val)
113 {
114 
115 	bus_write_4(sc->mem_res, off, val);
116 }
117 
118 static void
119 iomux_configure_input(struct iomux_softc *sc, uint32_t reg, uint32_t val)
120 {
121 	u_int select, mask, shift, width;
122 
123 	/* If register and value are zero, there is nothing to configure. */
124 	if (reg == 0 && val == 0)
125 		return;
126 
127 	/*
128 	 * If the config value has 0xff in the high byte it is encoded:
129 	 * 	31     23      15      7        0
130 	 *      | 0xff | shift | width | select |
131 	 * We need to mask out the old select value and OR in the new, using a
132 	 * mask of the given width and shifting the values up by shift.
133 	 */
134 	if ((val & 0xff000000) == 0xff000000) {
135 		select = val & 0x000000ff;
136 		width = (val & 0x0000ff00) >> 8;
137 		shift = (val & 0x00ff0000) >> 16;
138 		mask  = ((1u << width) - 1) << shift;
139 		val = (RD4(sc, reg) & ~mask) | (select << shift);
140 	}
141 	WR4(sc, reg, val);
142 }
143 
144 static int
145 iomux_configure_pins(device_t dev, phandle_t cfgxref)
146 {
147 	struct iomux_softc *sc;
148 	struct pincfg *cfgtuples, *cfg;
149 	phandle_t cfgnode;
150 	int i, ntuples;
151 	uint32_t sion;
152 
153 	sc = device_get_softc(dev);
154 	cfgnode = OF_node_from_xref(cfgxref);
155 	ntuples = OF_getencprop_alloc(cfgnode, "fsl,pins", sizeof(*cfgtuples),
156 	    (void **)&cfgtuples);
157 	if (ntuples < 0)
158 		return (ENOENT);
159 	if (ntuples == 0)
160 		return (0); /* Empty property is not an error. */
161 	for (i = 0, cfg = cfgtuples; i < ntuples; i++, cfg++) {
162 		sion = (cfg->padconf_val & PADCONF_SION) ? PADMUX_SION : 0;
163 		WR4(sc, cfg->mux_reg, cfg->mux_val | sion);
164 		iomux_configure_input(sc, cfg->input_reg, cfg->input_val);
165 		if ((cfg->padconf_val & PADCONF_NONE) == 0)
166 			WR4(sc, cfg->padconf_reg, cfg->padconf_val);
167 		if (bootverbose) {
168 			char name[32];
169 			OF_getprop(cfgnode, "name", &name, sizeof(name));
170 			printf("%16s: muxreg 0x%04x muxval 0x%02x "
171 			    "inpreg 0x%04x inpval 0x%02x "
172 			    "padreg 0x%04x padval 0x%08x\n",
173 			    name, cfg->mux_reg, cfg->mux_val | sion,
174 			    cfg->input_reg, cfg->input_val,
175 			    cfg->padconf_reg, cfg->padconf_val);
176 		}
177 	}
178 	OF_prop_free(cfgtuples);
179 	return (0);
180 }
181 
182 static int
183 iomux_probe(device_t dev)
184 {
185 
186 	if (!ofw_bus_status_okay(dev))
187 		return (ENXIO);
188 
189 	if (!ofw_bus_search_compatible(dev, compat_data)->ocd_data)
190 		return (ENXIO);
191 
192 	device_set_desc(dev, "Freescale i.MX pin configuration");
193 	return (BUS_PROBE_DEFAULT);
194 }
195 
196 static int
197 iomux_detach(device_t dev)
198 {
199 
200         /* This device is always present. */
201 	return (EBUSY);
202 }
203 
204 static int
205 iomux_attach(device_t dev)
206 {
207 	struct iomux_softc * sc;
208 	int rid;
209 
210 	sc = device_get_softc(dev);
211 	sc->dev = dev;
212 
213 	switch (imx_soc_type()) {
214 	case IMXSOC_51:
215 		sc->last_gpreg = 1;
216 		break;
217 	case IMXSOC_53:
218 		sc->last_gpreg = 2;
219 		break;
220 	case IMXSOC_6DL:
221 	case IMXSOC_6S:
222 	case IMXSOC_6SL:
223 	case IMXSOC_6Q:
224 		sc->last_gpreg = 13;
225 		break;
226 	default:
227 		device_printf(dev, "Unknown SoC type\n");
228 		return (ENXIO);
229 	}
230 
231 	rid = 0;
232 	sc->mem_res = bus_alloc_resource_any(dev, SYS_RES_MEMORY, &rid,
233 	    RF_ACTIVE);
234 	if (sc->mem_res == NULL) {
235 		device_printf(dev, "Cannot allocate memory resources\n");
236 		return (ENXIO);
237 	}
238 
239 	iomux_sc = sc;
240 
241 	/*
242 	 * Register as a pinctrl device, and call the convenience function that
243 	 * walks the entire device tree invoking FDT_PINCTRL_CONFIGURE() on any
244 	 * pinctrl-0 property cells whose xref phandle refers to a configuration
245 	 * that is a child node of our node in the tree.
246 	 *
247 	 * The pinctrl bindings documentation specifically mentions that the
248 	 * pinctrl device itself may have a pinctrl-0 property which contains
249 	 * static configuration to be applied at device init time.  The tree
250 	 * walk will automatically handle this for us when it passes through our
251 	 * node in the tree.
252 	 */
253 	fdt_pinctrl_register(dev, "fsl,pins");
254 	fdt_pinctrl_configure_tree(dev);
255 
256 	return (0);
257 }
258 
259 uint32_t
260 imx_iomux_gpr_get(u_int regnum)
261 {
262 	struct iomux_softc * sc;
263 
264 	sc = iomux_sc;
265 	KASSERT(sc != NULL, ("%s called before attach", __FUNCTION__));
266 	KASSERT(regnum >= 0 && regnum <= sc->last_gpreg,
267 	    ("%s bad regnum %u, max %u", __FUNCTION__, regnum, sc->last_gpreg));
268 
269 	return (RD4(iomux_sc, regnum * 4));
270 }
271 
272 void
273 imx_iomux_gpr_set(u_int regnum, uint32_t val)
274 {
275 	struct iomux_softc * sc;
276 
277 	sc = iomux_sc;
278 	KASSERT(sc != NULL, ("%s called before attach", __FUNCTION__));
279 	KASSERT(regnum >= 0 && regnum <= sc->last_gpreg,
280 	    ("%s bad regnum %u, max %u", __FUNCTION__, regnum, sc->last_gpreg));
281 
282 	WR4(iomux_sc, regnum * 4, val);
283 }
284 
285 void
286 imx_iomux_gpr_set_masked(u_int regnum, uint32_t clrbits, uint32_t setbits)
287 {
288 	struct iomux_softc * sc;
289 	uint32_t val;
290 
291 	sc = iomux_sc;
292 	KASSERT(sc != NULL, ("%s called before attach", __FUNCTION__));
293 	KASSERT(regnum >= 0 && regnum <= sc->last_gpreg,
294 	    ("%s bad regnum %u, max %u", __FUNCTION__, regnum, sc->last_gpreg));
295 
296 	val = RD4(iomux_sc, regnum * 4);
297 	val = (val & ~clrbits) | setbits;
298 	WR4(iomux_sc, regnum * 4, val);
299 }
300 
301 static device_method_t imx_iomux_methods[] = {
302 	/* Device interface */
303 	DEVMETHOD(device_probe,         iomux_probe),
304 	DEVMETHOD(device_attach,        iomux_attach),
305 	DEVMETHOD(device_detach,        iomux_detach),
306 
307         /* fdt_pinctrl interface */
308 	DEVMETHOD(fdt_pinctrl_configure,iomux_configure_pins),
309 
310 	DEVMETHOD_END
311 };
312 
313 static driver_t imx_iomux_driver = {
314 	"imx_iomux",
315 	imx_iomux_methods,
316 	sizeof(struct iomux_softc),
317 };
318 
319 static devclass_t imx_iomux_devclass;
320 
321 EARLY_DRIVER_MODULE(imx_iomux, simplebus, imx_iomux_driver,
322     imx_iomux_devclass, 0, 0, BUS_PASS_CPU + BUS_PASS_ORDER_LATE);
323 
324