xref: /freebsd/sys/arm/freescale/imx/imx_iomux.c (revision ff0ba87247820afbdfdc1b307c803f7923d0e4d3)
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 #define	PADCONF_NONE	(1U << 31)	/* Do not configure pad. */
103 #define	PADCONF_SION	(1U << 30)	/* Force SION bit in mux register. */
104 #define	PADMUX_SION	(1U <<  4)	/* The SION bit in the mux register. */
105 
106 static inline uint32_t
107 RD4(struct iomux_softc *sc, bus_size_t off)
108 {
109 
110 	return (bus_read_4(sc->mem_res, off));
111 }
112 
113 static inline void
114 WR4(struct iomux_softc *sc, bus_size_t off, uint32_t val)
115 {
116 
117 	bus_write_4(sc->mem_res, off, val);
118 }
119 
120 static int
121 iomux_configure_pins(device_t dev, phandle_t cfgxref)
122 {
123 	struct iomux_softc * sc;
124 	struct pincfg *cfgtuples, *cfg;
125 	phandle_t cfgnode;
126 	int i, ntuples;
127 	uint32_t sion;
128 
129 	sc = device_get_softc(dev);
130 	cfgnode = OF_node_from_xref(cfgxref);
131 	ntuples = OF_getencprop_alloc(cfgnode, "fsl,pins", sizeof(*cfgtuples),
132 	    (void **)&cfgtuples);
133 	if (ntuples < 0)
134 		return (ENOENT);
135 	if (ntuples == 0)
136 		return (0); /* Empty property is not an error. */
137 	for (i = 0, cfg = cfgtuples; i < ntuples; i++, cfg++) {
138 		sion = (cfg->padconf_val & PADCONF_SION) ? PADMUX_SION : 0;
139 		WR4(sc, cfg->mux_reg, cfg->mux_val | sion);
140 		if (cfg->input_reg != 0)
141 			WR4(sc, cfg->input_reg, cfg->input_val);
142 		if ((cfg->padconf_val & PADCONF_NONE) == 0)
143 			WR4(sc, cfg->padconf_reg, cfg->padconf_val);
144 		if (bootverbose) {
145 			char name[32];
146 			OF_getprop(cfgnode, "name", &name, sizeof(name));
147 			printf("%16s: muxreg 0x%04x muxval 0x%02x "
148 			    "inpreg 0x%04x inpval 0x%02x "
149 			    "padreg 0x%04x padval 0x%08x\n",
150 			    name, cfg->mux_reg, cfg->mux_val | sion,
151 			    cfg->input_reg, cfg->input_val,
152 			    cfg->padconf_reg, cfg->padconf_val);
153 		}
154 	}
155 	free(cfgtuples, M_OFWPROP);
156 	return (0);
157 }
158 
159 static int
160 iomux_probe(device_t dev)
161 {
162 
163 	if (!ofw_bus_status_okay(dev))
164 		return (ENXIO);
165 
166 	if (!ofw_bus_search_compatible(dev, compat_data)->ocd_data)
167 		return (ENXIO);
168 
169 	device_set_desc(dev, "Freescale i.MX pin configuration");
170 	return (BUS_PROBE_DEFAULT);
171 }
172 
173 static int
174 iomux_detach(device_t dev)
175 {
176 
177         /* This device is always present. */
178 	return (EBUSY);
179 }
180 
181 static int
182 iomux_attach(device_t dev)
183 {
184 	struct iomux_softc * sc;
185 	int rid;
186 
187 	sc = device_get_softc(dev);
188 	sc->dev = dev;
189 
190 	switch (imx_soc_type()) {
191 	case IMXSOC_51:
192 		sc->last_gpreg = 1;
193 		break;
194 	case IMXSOC_53:
195 		sc->last_gpreg = 2;
196 		break;
197 	case IMXSOC_6DL:
198 	case IMXSOC_6S:
199 	case IMXSOC_6SL:
200 	case IMXSOC_6Q:
201 		sc->last_gpreg = 13;
202 		break;
203 	default:
204 		device_printf(dev, "Unknown SoC type\n");
205 		return (ENXIO);
206 	}
207 
208 	rid = 0;
209 	sc->mem_res = bus_alloc_resource_any(dev, SYS_RES_MEMORY, &rid,
210 	    RF_ACTIVE);
211 	if (sc->mem_res == NULL) {
212 		device_printf(dev, "Cannot allocate memory resources\n");
213 		return (ENXIO);
214 	}
215 
216 	iomux_sc = sc;
217 
218 	/*
219 	 * Register as a pinctrl device, and call the convenience function that
220 	 * walks the entire device tree invoking FDT_PINCTRL_CONFIGURE() on any
221 	 * pinctrl-0 property cells whose xref phandle refers to a configuration
222 	 * that is a child node of our node in the tree.
223 	 *
224 	 * The pinctrl bindings documentation specifically mentions that the
225 	 * pinctrl device itself may have a pinctrl-0 property which contains
226 	 * static configuration to be applied at device init time.  The tree
227 	 * walk will automatically handle this for us when it passes through our
228 	 * node in the tree.
229 	 */
230 	fdt_pinctrl_register(dev, "fsl,pins");
231 	fdt_pinctrl_configure_tree(dev);
232 
233 	return (0);
234 }
235 
236 uint32_t
237 imx_iomux_gpr_get(u_int regnum)
238 {
239 	struct iomux_softc * sc;
240 
241 	sc = iomux_sc;
242 	KASSERT(sc != NULL, ("%s called before attach", __FUNCTION__));
243 	KASSERT(regnum >= 0 && regnum <= sc->last_gpreg,
244 	    ("%s bad regnum %u, max %u", __FUNCTION__, regnum, sc->last_gpreg));
245 
246 	return (RD4(iomux_sc, regnum * 4));
247 }
248 
249 void
250 imx_iomux_gpr_set(u_int regnum, uint32_t val)
251 {
252 	struct iomux_softc * sc;
253 
254 	sc = iomux_sc;
255 	KASSERT(sc != NULL, ("%s called before attach", __FUNCTION__));
256 	KASSERT(regnum >= 0 && regnum <= sc->last_gpreg,
257 	    ("%s bad regnum %u, max %u", __FUNCTION__, regnum, sc->last_gpreg));
258 
259 	WR4(iomux_sc, regnum * 4, val);
260 }
261 
262 void
263 imx_iomux_gpr_set_masked(u_int regnum, uint32_t clrbits, uint32_t setbits)
264 {
265 	struct iomux_softc * sc;
266 	uint32_t val;
267 
268 	sc = iomux_sc;
269 	KASSERT(sc != NULL, ("%s called before attach", __FUNCTION__));
270 	KASSERT(regnum >= 0 && regnum <= sc->last_gpreg,
271 	    ("%s bad regnum %u, max %u", __FUNCTION__, regnum, sc->last_gpreg));
272 
273 	val = RD4(iomux_sc, regnum * 4);
274 	val = (val & ~clrbits) | setbits;
275 	WR4(iomux_sc, regnum * 4, val);
276 }
277 
278 static device_method_t imx_iomux_methods[] = {
279 	/* Device interface */
280 	DEVMETHOD(device_probe,         iomux_probe),
281 	DEVMETHOD(device_attach,        iomux_attach),
282 	DEVMETHOD(device_detach,        iomux_detach),
283 
284         /* fdt_pinctrl interface */
285 	DEVMETHOD(fdt_pinctrl_configure,iomux_configure_pins),
286 
287 	DEVMETHOD_END
288 };
289 
290 static driver_t imx_iomux_driver = {
291 	"imx_iomux",
292 	imx_iomux_methods,
293 	sizeof(struct iomux_softc),
294 };
295 
296 static devclass_t imx_iomux_devclass;
297 
298 EARLY_DRIVER_MODULE(imx_iomux, simplebus, imx_iomux_driver,
299     imx_iomux_devclass, 0, 0, BUS_PASS_CPU + BUS_PASS_ORDER_LATE);
300 
301