xref: /freebsd/sys/arm/freescale/imx/imx_iomux.c (revision 7431dfd4580e850375fe5478d92ec770344db098)
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 #include <machine/fdt.h>
62 
63 #include <dev/fdt/fdt_common.h>
64 #include <dev/fdt/fdt_pinctrl.h>
65 #include <dev/ofw/openfirm.h>
66 #include <dev/ofw/ofw_bus.h>
67 #include <dev/ofw/ofw_bus_subr.h>
68 
69 #include <arm/freescale/imx/imx_iomuxvar.h>
70 #include <arm/freescale/imx/imx_machdep.h>
71 
72 struct iomux_softc {
73 	device_t	dev;
74 	struct resource	*mem_res;
75 	u_int		last_gpreg;
76 };
77 
78 static struct iomux_softc *iomux_sc;
79 
80 static struct ofw_compat_data compat_data[] = {
81 	{"fsl,imx6dl-iomuxc",	true},
82 	{"fsl,imx6q-iomuxc",	true},
83 	{"fsl,imx6sl-iomuxc",	true},
84 	{"fsl,imx6sx-iomuxc",	true},
85 	{"fsl,imx53-iomuxc",	true},
86 	{"fsl,imx51-iomuxc",	true},
87 	{NULL,			false},
88 };
89 
90 /*
91  * Each tuple in an fsl,pins property contains these fields.
92  */
93 struct pincfg {
94 	uint32_t mux_reg;
95 	uint32_t padconf_reg;
96 	uint32_t input_reg;
97 	uint32_t mux_val;
98 	uint32_t input_val;
99 	uint32_t padconf_val;
100 };
101 
102 static inline uint32_t
103 RD4(struct iomux_softc *sc, bus_size_t off)
104 {
105 
106 	return (bus_read_4(sc->mem_res, off));
107 }
108 
109 static inline void
110 WR4(struct iomux_softc *sc, bus_size_t off, uint32_t val)
111 {
112 
113 	bus_write_4(sc->mem_res, off, val);
114 }
115 
116 static int
117 iomux_configure_pins(device_t dev, phandle_t cfgxref)
118 {
119 	struct iomux_softc * sc;
120 	struct pincfg *cfgtuples, *cfg;
121 	phandle_t cfgnode;
122 	int i, ntuples;
123 
124 	sc = device_get_softc(dev);
125 	cfgnode = OF_node_from_xref(cfgxref);
126 	ntuples = OF_getencprop_alloc(cfgnode, "fsl,pins", sizeof(*cfgtuples),
127 	    (void **)&cfgtuples);
128 	if (ntuples < 0)
129 		return (ENOENT);
130 	if (ntuples == 0)
131 		return (0); /* Empty property is not an error. */
132 	for (i = 0, cfg = cfgtuples; i < ntuples; i++, cfg++) {
133 		WR4(sc, cfg->mux_reg, cfg->mux_val);
134 		WR4(sc, cfg->input_reg, cfg->input_val);
135 		WR4(sc, cfg->padconf_reg, cfg->padconf_val);
136 	}
137 	free(cfgtuples, M_OFWPROP);
138 	return (0);
139 }
140 
141 static int
142 iomux_probe(device_t dev)
143 {
144 
145 	if (!ofw_bus_status_okay(dev))
146 		return (ENXIO);
147 
148 	if (!ofw_bus_search_compatible(dev, compat_data)->ocd_data)
149 		return (ENXIO);
150 
151 	device_set_desc(dev, "Freescale i.MX pin configuration");
152 	return (BUS_PROBE_DEFAULT);
153 }
154 
155 static int
156 iomux_detach(device_t dev)
157 {
158 
159         /* This device is always present. */
160 	return (EBUSY);
161 }
162 
163 static int
164 iomux_attach(device_t dev)
165 {
166 	struct iomux_softc * sc;
167 	int rid;
168 
169 	sc = device_get_softc(dev);
170 	sc->dev = dev;
171 
172 	switch (imx_soc_type()) {
173 	case IMXSOC_51:
174 		sc->last_gpreg = 1;
175 		break;
176 	case IMXSOC_53:
177 		sc->last_gpreg = 2;
178 		break;
179 	case IMXSOC_6DL:
180 	case IMXSOC_6S:
181 	case IMXSOC_6SL:
182 	case IMXSOC_6Q:
183 		sc->last_gpreg = 13;
184 		break;
185 	default:
186 		device_printf(dev, "Unknown SoC type\n");
187 		return (ENXIO);
188 	}
189 
190 	rid = 0;
191 	sc->mem_res = bus_alloc_resource_any(dev, SYS_RES_MEMORY, &rid,
192 	    RF_ACTIVE);
193 	if (sc->mem_res == NULL) {
194 		device_printf(dev, "Cannot allocate memory resources\n");
195 		return (ENXIO);
196 	}
197 
198 	iomux_sc = sc;
199 
200 	/*
201 	 * Register as a pinctrl device, and call the convenience function that
202 	 * walks the entire device tree invoking FDT_PINCTRL_CONFIGURE() on any
203 	 * pinctrl-0 property cells whose xref phandle refers to a configuration
204 	 * that is a child node of our node in the tree.
205 	 *
206 	 * The pinctrl bindings documentation specifically mentions that the
207 	 * pinctrl device itself may have a pinctrl-0 property which contains
208 	 * static configuration to be applied at device init time.  The tree
209 	 * walk will automatically handle this for us when it passes through our
210 	 * node in the tree.
211 	 */
212 	fdt_pinctrl_register(dev, "fsl,pins");
213 	fdt_pinctrl_configure_tree(dev);
214 
215 	return (0);
216 }
217 
218 uint32_t
219 imx_iomux_gpr_get(u_int regnum)
220 {
221 	struct iomux_softc * sc;
222 
223 	sc = iomux_sc;
224 	KASSERT(sc != NULL, ("%s called before attach", __FUNCTION__));
225 	KASSERT(regnum >= 0 && regnum <= sc->last_gpreg,
226 	    ("%s bad regnum %u, max %u", __FUNCTION__, regnum, sc->last_gpreg));
227 
228 	return (RD4(iomux_sc, regnum * 4));
229 }
230 
231 void
232 imx_iomux_gpr_set(u_int regnum, uint32_t val)
233 {
234 	struct iomux_softc * sc;
235 
236 	sc = iomux_sc;
237 	KASSERT(sc != NULL, ("%s called before attach", __FUNCTION__));
238 	KASSERT(regnum >= 0 && regnum <= sc->last_gpreg,
239 	    ("%s bad regnum %u, max %u", __FUNCTION__, regnum, sc->last_gpreg));
240 
241 	WR4(iomux_sc, regnum * 4, val);
242 }
243 
244 void
245 imx_iomux_gpr_set_masked(u_int regnum, uint32_t clrbits, uint32_t setbits)
246 {
247 	struct iomux_softc * sc;
248 	uint32_t val;
249 
250 	sc = iomux_sc;
251 	KASSERT(sc != NULL, ("%s called before attach", __FUNCTION__));
252 	KASSERT(regnum >= 0 && regnum <= sc->last_gpreg,
253 	    ("%s bad regnum %u, max %u", __FUNCTION__, regnum, sc->last_gpreg));
254 
255 	val = RD4(iomux_sc, regnum * 4);
256 	val = (val & ~clrbits) | setbits;
257 	WR4(iomux_sc, regnum * 4, val);
258 }
259 
260 static device_method_t imx_iomux_methods[] = {
261 	/* Device interface */
262 	DEVMETHOD(device_probe,         iomux_probe),
263 	DEVMETHOD(device_attach,        iomux_attach),
264 	DEVMETHOD(device_detach,        iomux_detach),
265 
266         /* fdt_pinctrl interface */
267 	DEVMETHOD(fdt_pinctrl_configure,iomux_configure_pins),
268 
269 	DEVMETHOD_END
270 };
271 
272 static driver_t imx_iomux_driver = {
273 	"imx_iomux",
274 	imx_iomux_methods,
275 	sizeof(struct iomux_softc),
276 };
277 
278 static devclass_t imx_iomux_devclass;
279 
280 EARLY_DRIVER_MODULE(imx_iomux, simplebus, imx_iomux_driver,
281     imx_iomux_devclass, 0, 0, BUS_PASS_CPU + BUS_PASS_ORDER_LATE);
282 
283