imx6_anatop.c revision 266152 
1/*-
2 * Copyright (c) 2013 Ian Lepore <ian@freebsd.org>
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
27#include <sys/cdefs.h>
28__FBSDID("$FreeBSD: stable/10/sys/arm/freescale/imx/imx6_anatop.c 266152 2014-05-15 16:11:06Z ian $");
29
30/*
31 * Analog PLL and power regulator driver for Freescale i.MX6 family of SoCs.
32 *
33 * We don't really do anything with analog PLLs, but the registers for
34 * controlling them belong to the same block as the power regulator registers.
35 * Since the newbus hierarchy makes it hard for anyone other than us to get at
36 * them, we just export a couple public functions to allow the imx6 CCM clock
37 * driver to read and write those registers.
38 *
39 * We also don't do anything about power regulation yet, but when the need
40 * arises, this would be the place for that code to live.
41 *
42 * I have no idea where the "anatop" name comes from.  It's in the standard DTS
43 * source describing i.MX6 SoCs, and in the linux and u-boot code which comes
44 * from Freescale, but it's not in the SoC manual.
45 */
46
47#include <sys/param.h>
48#include <sys/systm.h>
49#include <sys/kernel.h>
50#include <sys/module.h>
51#include <sys/bus.h>
52#include <sys/rman.h>
53
54#include <dev/ofw/ofw_bus.h>
55#include <dev/ofw/ofw_bus_subr.h>
56
57#include <machine/bus.h>
58
59#include <arm/freescale/imx/imx6_anatopreg.h>
60#include <arm/freescale/imx/imx6_anatopvar.h>
61
62struct imx6_anatop_softc {
63	device_t	dev;
64	struct resource	*mem_res;
65};
66
67static struct imx6_anatop_softc *imx6_anatop_sc;
68
69uint32_t
70imx6_anatop_read_4(bus_size_t offset)
71{
72
73	return (bus_read_4(imx6_anatop_sc->mem_res, offset));
74}
75
76void
77imx6_anatop_write_4(bus_size_t offset, uint32_t value)
78{
79
80	bus_write_4(imx6_anatop_sc->mem_res, offset, value);
81}
82
83static int
84imx6_anatop_detach(device_t dev)
85{
86	struct imx6_anatop_softc *sc;
87
88	sc = device_get_softc(dev);
89
90	if (sc->mem_res != NULL)
91		bus_release_resource(dev, SYS_RES_MEMORY, 0, sc->mem_res);
92
93	return (0);
94}
95
96static int
97imx6_anatop_attach(device_t dev)
98{
99	struct imx6_anatop_softc *sc;
100	int err, rid;
101
102	sc = device_get_softc(dev);
103
104	/* Allocate bus_space resources. */
105	rid = 0;
106	sc->mem_res = bus_alloc_resource_any(dev, SYS_RES_MEMORY, &rid,
107	    RF_ACTIVE);
108	if (sc->mem_res == NULL) {
109		device_printf(dev, "Cannot allocate memory resources\n");
110		err = ENXIO;
111		goto out;
112	}
113
114	imx6_anatop_sc = sc;
115	err = 0;
116
117out:
118
119	if (err != 0)
120		imx6_anatop_detach(dev);
121
122	return (err);
123}
124
125static int
126imx6_anatop_probe(device_t dev)
127{
128
129	if (!ofw_bus_status_okay(dev))
130		return (ENXIO);
131
132        if (ofw_bus_is_compatible(dev, "fsl,imx6q-anatop") == 0)
133		return (ENXIO);
134
135	device_set_desc(dev, "Freescale i.MX6 Analog PLLs and Power");
136
137	return (BUS_PROBE_DEFAULT);
138}
139
140static device_method_t imx6_anatop_methods[] = {
141	/* Device interface */
142	DEVMETHOD(device_probe,  imx6_anatop_probe),
143	DEVMETHOD(device_attach, imx6_anatop_attach),
144	DEVMETHOD(device_detach, imx6_anatop_detach),
145
146	DEVMETHOD_END
147};
148
149static driver_t imx6_anatop_driver = {
150	"imx6_anatop",
151	imx6_anatop_methods,
152	sizeof(struct imx6_anatop_softc)
153};
154
155static devclass_t imx6_anatop_devclass;
156
157DRIVER_MODULE(imx6_anatop, simplebus, imx6_anatop_driver, imx6_anatop_devclass, 0, 0);
158
159