xref: /freebsd/sys/arm/freescale/imx/imx_iomux.c (revision 7447ca0eb235974642312b9555caec00b57d8fc1)
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/fdt/fdt_common.h>
63 #include <dev/fdt/fdt_pinctrl.h>
64 #include <dev/ofw/openfirm.h>
65 #include <dev/ofw/ofw_bus.h>
66 #include <dev/ofw/ofw_bus_subr.h>
67 
68 #include <arm/freescale/imx/imx_iomuxvar.h>
69 #include <arm/freescale/imx/imx_machdep.h>
70 
71 struct iomux_softc {
72 	device_t	dev;
73 	struct resource	*mem_res;
74 	u_int		last_gpreg;
75 };
76 
77 static struct iomux_softc *iomux_sc;
78 
79 static struct ofw_compat_data compat_data[] = {
80 	{"fsl,imx6dl-iomuxc",	true},
81 	{"fsl,imx6q-iomuxc",	true},
82 	{"fsl,imx6sl-iomuxc",	true},
83 	{"fsl,imx6sx-iomuxc",	true},
84 	{"fsl,imx53-iomuxc",	true},
85 	{"fsl,imx51-iomuxc",	true},
86 	{NULL,			false},
87 };
88 
89 /*
90  * Each tuple in an fsl,pins property contains these fields.
91  */
92 struct pincfg {
93 	uint32_t mux_reg;
94 	uint32_t padconf_reg;
95 	uint32_t input_reg;
96 	uint32_t mux_val;
97 	uint32_t input_val;
98 	uint32_t padconf_val;
99 };
100 
101 #define	PADCONF_NONE	(1U << 31)	/* Do not configure pad. */
102 #define	PADCONF_SION	(1U << 30)	/* Force SION bit in mux register. */
103 #define	PADMUX_SION	(1U <<  4)	/* The SION bit in the mux register. */
104 
105 static inline uint32_t
106 RD4(struct iomux_softc *sc, bus_size_t off)
107 {
108 
109 	return (bus_read_4(sc->mem_res, off));
110 }
111 
112 static inline void
113 WR4(struct iomux_softc *sc, bus_size_t off, uint32_t val)
114 {
115 
116 	bus_write_4(sc->mem_res, off, val);
117 }
118 
119 static void
120 iomux_configure_input(struct iomux_softc *sc, uint32_t reg, uint32_t val)
121 {
122 	u_int select, mask, shift, width;
123 
124 	/* If register and value are zero, there is nothing to configure. */
125 	if (reg == 0 && val == 0)
126 		return;
127 
128 	/*
129 	 * If the config value has 0xff in the high byte it is encoded:
130 	 * 	31     23      15      7        0
131 	 *      | 0xff | shift | width | select |
132 	 * We need to mask out the old select value and OR in the new, using a
133 	 * mask of the given width and shifting the values up by shift.
134 	 */
135 	if ((val & 0xff000000) == 0xff000000) {
136 		select = val & 0x000000ff;
137 		width = (val & 0x0000ff00) >> 8;
138 		shift = (val & 0x00ff0000) >> 16;
139 		mask  = ((1u << width) - 1) << shift;
140 		val = (RD4(sc, reg) & ~mask) | (select << shift);
141 	}
142 	WR4(sc, reg, val);
143 }
144 
145 static int
146 iomux_configure_pins(device_t dev, phandle_t cfgxref)
147 {
148 	struct iomux_softc *sc;
149 	struct pincfg *cfgtuples, *cfg;
150 	phandle_t cfgnode;
151 	int i, ntuples;
152 	uint32_t sion;
153 
154 	sc = device_get_softc(dev);
155 	cfgnode = OF_node_from_xref(cfgxref);
156 	ntuples = OF_getencprop_alloc(cfgnode, "fsl,pins", sizeof(*cfgtuples),
157 	    (void **)&cfgtuples);
158 	if (ntuples < 0)
159 		return (ENOENT);
160 	if (ntuples == 0)
161 		return (0); /* Empty property is not an error. */
162 	for (i = 0, cfg = cfgtuples; i < ntuples; i++, cfg++) {
163 		sion = (cfg->padconf_val & PADCONF_SION) ? PADMUX_SION : 0;
164 		WR4(sc, cfg->mux_reg, cfg->mux_val | sion);
165 		iomux_configure_input(sc, cfg->input_reg, cfg->input_val);
166 		if ((cfg->padconf_val & PADCONF_NONE) == 0)
167 			WR4(sc, cfg->padconf_reg, cfg->padconf_val);
168 		if (bootverbose) {
169 			char name[32];
170 			OF_getprop(cfgnode, "name", &name, sizeof(name));
171 			printf("%16s: muxreg 0x%04x muxval 0x%02x "
172 			    "inpreg 0x%04x inpval 0x%02x "
173 			    "padreg 0x%04x padval 0x%08x\n",
174 			    name, cfg->mux_reg, cfg->mux_val | sion,
175 			    cfg->input_reg, cfg->input_val,
176 			    cfg->padconf_reg, cfg->padconf_val);
177 		}
178 	}
179 	OF_prop_free(cfgtuples);
180 	return (0);
181 }
182 
183 static int
184 iomux_probe(device_t dev)
185 {
186 
187 	if (!ofw_bus_status_okay(dev))
188 		return (ENXIO);
189 
190 	if (!ofw_bus_search_compatible(dev, compat_data)->ocd_data)
191 		return (ENXIO);
192 
193 	device_set_desc(dev, "Freescale i.MX pin configuration");
194 	return (BUS_PROBE_DEFAULT);
195 }
196 
197 static int
198 iomux_detach(device_t dev)
199 {
200 
201         /* This device is always present. */
202 	return (EBUSY);
203 }
204 
205 static int
206 iomux_attach(device_t dev)
207 {
208 	struct iomux_softc * sc;
209 	int rid;
210 
211 	sc = device_get_softc(dev);
212 	sc->dev = dev;
213 
214 	switch (imx_soc_type()) {
215 	case IMXSOC_51:
216 		sc->last_gpreg = 1;
217 		break;
218 	case IMXSOC_53:
219 		sc->last_gpreg = 2;
220 		break;
221 	case IMXSOC_6DL:
222 	case IMXSOC_6S:
223 	case IMXSOC_6SL:
224 	case IMXSOC_6Q:
225 		sc->last_gpreg = 13;
226 		break;
227 	default:
228 		device_printf(dev, "Unknown SoC type\n");
229 		return (ENXIO);
230 	}
231 
232 	rid = 0;
233 	sc->mem_res = bus_alloc_resource_any(dev, SYS_RES_MEMORY, &rid,
234 	    RF_ACTIVE);
235 	if (sc->mem_res == NULL) {
236 		device_printf(dev, "Cannot allocate memory resources\n");
237 		return (ENXIO);
238 	}
239 
240 	iomux_sc = sc;
241 
242 	/*
243 	 * Register as a pinctrl device, and call the convenience function that
244 	 * walks the entire device tree invoking FDT_PINCTRL_CONFIGURE() on any
245 	 * pinctrl-0 property cells whose xref phandle refers to a configuration
246 	 * that is a child node of our node in the tree.
247 	 *
248 	 * The pinctrl bindings documentation specifically mentions that the
249 	 * pinctrl device itself may have a pinctrl-0 property which contains
250 	 * static configuration to be applied at device init time.  The tree
251 	 * walk will automatically handle this for us when it passes through our
252 	 * node in the tree.
253 	 */
254 	fdt_pinctrl_register(dev, "fsl,pins");
255 	fdt_pinctrl_configure_tree(dev);
256 
257 	return (0);
258 }
259 
260 uint32_t
261 imx_iomux_gpr_get(u_int regnum)
262 {
263 	struct iomux_softc * sc;
264 
265 	sc = iomux_sc;
266 	KASSERT(sc != NULL, ("%s called before attach", __FUNCTION__));
267 	KASSERT(regnum >= 0 && regnum <= sc->last_gpreg,
268 	    ("%s bad regnum %u, max %u", __FUNCTION__, regnum, sc->last_gpreg));
269 
270 	return (RD4(iomux_sc, regnum * 4));
271 }
272 
273 void
274 imx_iomux_gpr_set(u_int regnum, uint32_t val)
275 {
276 	struct iomux_softc * sc;
277 
278 	sc = iomux_sc;
279 	KASSERT(sc != NULL, ("%s called before attach", __FUNCTION__));
280 	KASSERT(regnum >= 0 && regnum <= sc->last_gpreg,
281 	    ("%s bad regnum %u, max %u", __FUNCTION__, regnum, sc->last_gpreg));
282 
283 	WR4(iomux_sc, regnum * 4, val);
284 }
285 
286 void
287 imx_iomux_gpr_set_masked(u_int regnum, uint32_t clrbits, uint32_t setbits)
288 {
289 	struct iomux_softc * sc;
290 	uint32_t val;
291 
292 	sc = iomux_sc;
293 	KASSERT(sc != NULL, ("%s called before attach", __FUNCTION__));
294 	KASSERT(regnum >= 0 && regnum <= sc->last_gpreg,
295 	    ("%s bad regnum %u, max %u", __FUNCTION__, regnum, sc->last_gpreg));
296 
297 	val = RD4(iomux_sc, regnum * 4);
298 	val = (val & ~clrbits) | setbits;
299 	WR4(iomux_sc, regnum * 4, val);
300 }
301 
302 static device_method_t imx_iomux_methods[] = {
303 	/* Device interface */
304 	DEVMETHOD(device_probe,         iomux_probe),
305 	DEVMETHOD(device_attach,        iomux_attach),
306 	DEVMETHOD(device_detach,        iomux_detach),
307 
308         /* fdt_pinctrl interface */
309 	DEVMETHOD(fdt_pinctrl_configure,iomux_configure_pins),
310 
311 	DEVMETHOD_END
312 };
313 
314 static driver_t imx_iomux_driver = {
315 	"imx_iomux",
316 	imx_iomux_methods,
317 	sizeof(struct iomux_softc),
318 };
319 
320 static devclass_t imx_iomux_devclass;
321 
322 EARLY_DRIVER_MODULE(imx_iomux, simplebus, imx_iomux_driver,
323     imx_iomux_devclass, 0, 0, BUS_PASS_CPU + BUS_PASS_ORDER_LATE);
324 
325