xref: /freebsd/sys/dev/hwreset/hwreset.c (revision 96190b4fef3b4a0cc3ca0606b0c4e3e69a5e6717)
1 /*-
2  * Copyright 2016 Michal Meloun <mmel@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 #include "opt_platform.h"
27 
28 #include <sys/param.h>
29 #include <sys/kernel.h>
30 #include <sys/kobj.h>
31 #include <sys/malloc.h>
32 #include <sys/systm.h>
33 
34 #ifdef FDT
35 #include <dev/ofw/ofw_bus.h>
36 #include <dev/ofw/ofw_bus_subr.h>
37 #endif
38 
39 #include <dev/hwreset/hwreset.h>
40 
41 #include "hwreset_if.h"
42 
43 struct hwreset {
44 	device_t consumer_dev;		/* consumer device*/
45 	device_t provider_dev;		/* provider device*/
46 	int 	rst_id;			/* reset id */
47 };
48 
49 MALLOC_DEFINE(M_HWRESET, "hwreset", "Reset framework");
50 
51 int
52 hwreset_assert(hwreset_t rst)
53 {
54 
55 	return (HWRESET_ASSERT(rst->provider_dev, rst->rst_id, true));
56 }
57 
58 int
59 hwreset_deassert(hwreset_t rst)
60 {
61 
62 	return (HWRESET_ASSERT(rst->provider_dev, rst->rst_id, false));
63 }
64 
65 int
66 hwreset_is_asserted(hwreset_t rst, bool *value)
67 {
68 
69 	return (HWRESET_IS_ASSERTED(rst->provider_dev, rst->rst_id, value));
70 }
71 
72 void
73 hwreset_release(hwreset_t rst)
74 {
75 	free(rst, M_HWRESET);
76 }
77 
78 int
79 hwreset_get_by_id(device_t consumer_dev, device_t provider_dev, intptr_t id,
80     hwreset_t *rst_out)
81 {
82 	hwreset_t rst;
83 
84 	/* Create handle */
85 	rst = malloc(sizeof(struct hwreset), M_HWRESET,
86 	    M_WAITOK | M_ZERO);
87 	rst->consumer_dev = consumer_dev;
88 	rst->provider_dev = provider_dev;
89 	rst->rst_id = id;
90 	*rst_out = rst;
91 	return (0);
92 }
93 
94 #ifdef FDT
95 int
96 hwreset_default_ofw_map(device_t provider_dev, phandle_t xref, int ncells,
97     pcell_t *cells, intptr_t *id)
98 {
99 	if (ncells == 0)
100 		*id = 1;
101 	else if (ncells == 1)
102 		*id = cells[0];
103 	else
104 		return  (ERANGE);
105 
106 	return (0);
107 }
108 
109 int
110 hwreset_get_by_ofw_idx(device_t consumer_dev, phandle_t cnode, int idx,
111     hwreset_t *rst)
112 {
113 	phandle_t xnode;
114 	pcell_t *cells;
115 	device_t rstdev;
116 	int ncells, rv;
117 	intptr_t id;
118 
119 	if (cnode <= 0)
120 		cnode = ofw_bus_get_node(consumer_dev);
121 	if (cnode <= 0) {
122 		device_printf(consumer_dev,
123 		    "%s called on not ofw based device\n", __func__);
124 		return (ENXIO);
125 	}
126 
127 	rv = ofw_bus_parse_xref_list_alloc(cnode, "resets", "#reset-cells",
128 	    idx, &xnode, &ncells, &cells);
129 	if (rv != 0)
130 		return (rv);
131 
132 	/* Tranlate provider to device */
133 	rstdev = OF_device_from_xref(xnode);
134 	if (rstdev == NULL) {
135 		OF_prop_free(cells);
136 		return (ENODEV);
137 	}
138 	/* Map reset to number */
139 	rv = HWRESET_MAP(rstdev, xnode, ncells, cells, &id);
140 	OF_prop_free(cells);
141 	if (rv != 0)
142 		return (rv);
143 
144 	return (hwreset_get_by_id(consumer_dev, rstdev, id, rst));
145 }
146 
147 int
148 hwreset_get_by_ofw_name(device_t consumer_dev, phandle_t cnode, char *name,
149     hwreset_t *rst)
150 {
151 	int rv, idx;
152 
153 	if (cnode <= 0)
154 		cnode = ofw_bus_get_node(consumer_dev);
155 	if (cnode <= 0) {
156 		device_printf(consumer_dev,
157 		    "%s called on not ofw based device\n",  __func__);
158 		return (ENXIO);
159 	}
160 	rv = ofw_bus_find_string_index(cnode, "reset-names", name, &idx);
161 	if (rv != 0)
162 		return (rv);
163 	return (hwreset_get_by_ofw_idx(consumer_dev, cnode, idx, rst));
164 }
165 
166 void
167 hwreset_register_ofw_provider(device_t provider_dev)
168 {
169 	phandle_t xref, node;
170 
171 	node = ofw_bus_get_node(provider_dev);
172 	if (node <= 0)
173 		panic("%s called on not ofw based device.\n", __func__);
174 
175 	xref = OF_xref_from_node(node);
176 	OF_device_register_xref(xref, provider_dev);
177 }
178 
179 void
180 hwreset_unregister_ofw_provider(device_t provider_dev)
181 {
182 	phandle_t xref;
183 
184 	xref = OF_xref_from_device(provider_dev);
185 	OF_device_register_xref(xref, NULL);
186 }
187 #endif
188