1/*-
2 * Copyright (c) 2014 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 * $FreeBSD$
27 */
28
29#include <sys/cdefs.h>
30#include <sys/param.h>
31#include <sys/kernel.h>
32#include <sys/lock.h>
33#include <sys/mutex.h>
34#include <sys/queue.h>
35#include <sys/systm.h>
36
37#include <dev/ofw/ofw_bus.h>
38#include <dev/ofw/ofw_bus_subr.h>
39
40#include "fdt_clock_if.h"
41#include <dev/fdt/fdt_clock.h>
42
43/*
44 * Loop through all the tuples in the clocks= property for a device, enabling or
45 * disabling each clock.
46 *
47 * Be liberal about errors for now: warn about a failure to enable but keep
48 * trying with any other clocks in the list.  Return ENXIO if any errors were
49 * found, and let the caller decide whether the problem is fatal.
50 */
51static int
52enable_disable_all(device_t consumer, boolean_t enable)
53{
54	phandle_t cnode;
55	device_t clockdev;
56	int clocknum, err, i, ncells;
57	uint32_t *clks;
58	boolean_t anyerrors;
59
60	cnode = ofw_bus_get_node(consumer);
61	ncells = OF_getencprop_alloc_multi(cnode, "clocks", sizeof(*clks),
62	    (void **)&clks);
63	if (enable && ncells < 2) {
64		device_printf(consumer, "Warning: No clocks specified in fdt "
65		    "data; device may not function.");
66		return (ENXIO);
67	}
68	anyerrors = false;
69	for (i = 0; i < ncells; i += 2) {
70		clockdev = OF_device_from_xref(clks[i]);
71		clocknum = clks[i + 1];
72		if (clockdev == NULL) {
73			if (enable)
74				device_printf(consumer, "Warning: can not find "
75				    "driver for clock number %u; device may not "
76				    "function\n", clocknum);
77			anyerrors = true;
78			continue;
79		}
80		if (enable)
81			err = FDT_CLOCK_ENABLE(clockdev, clocknum);
82		else
83			err = FDT_CLOCK_DISABLE(clockdev, clocknum);
84		if (err != 0) {
85			if (enable)
86				device_printf(consumer, "Warning: failed to "
87				    "enable clock number %u; device may not "
88				    "function\n", clocknum);
89			anyerrors = true;
90		}
91	}
92	OF_prop_free(clks);
93	return (anyerrors ? ENXIO : 0);
94}
95
96int
97fdt_clock_get_info(device_t consumer, int n, struct fdt_clock_info *info)
98{
99	phandle_t cnode;
100	device_t clockdev;
101	int clocknum, err, ncells;
102	uint32_t *clks;
103
104	cnode = ofw_bus_get_node(consumer);
105	ncells = OF_getencprop_alloc_multi(cnode, "clocks", sizeof(*clks),
106	    (void **)&clks);
107	if (ncells <= 0)
108		return (ENXIO);
109	n *= 2;
110	if (ncells <= n)
111		err = ENXIO;
112	else {
113		clockdev = OF_device_from_xref(clks[n]);
114		if (clockdev == NULL)
115			err = ENXIO;
116		else  {
117			/*
118			 * Make struct contents minimally valid, then call
119			 * provider to fill in what it knows (provider can
120			 * override anything it wants to).
121			 */
122			clocknum = clks[n + 1];
123			bzero(info, sizeof(*info));
124			info->provider = clockdev;
125			info->index = clocknum;
126			info->name = "";
127			err = FDT_CLOCK_GET_INFO(clockdev, clocknum, info);
128		}
129	}
130	OF_prop_free(clks);
131	return (err);
132}
133
134int
135fdt_clock_enable_all(device_t consumer)
136{
137
138	return (enable_disable_all(consumer, true));
139}
140
141int
142fdt_clock_disable_all(device_t consumer)
143{
144
145	return (enable_disable_all(consumer, false));
146}
147
148void
149fdt_clock_register_provider(device_t provider)
150{
151
152	OF_device_register_xref(
153	    OF_xref_from_node(ofw_bus_get_node(provider)), provider);
154}
155
156void
157fdt_clock_unregister_provider(device_t provider)
158{
159
160	OF_device_register_xref(OF_xref_from_device(provider), NULL);
161}
162
163