1 /* $NetBSD: fdt_mbox.c,v 1.1 2022/03/04 08:19:06 skrll Exp $ */
2
3 /*-
4 * Copyright (c) 2022 The NetBSD Foundation, Inc.
5 * All rights reserved.
6 *
7 * This code is derived from software contributed to The NetBSD Foundation
8 * by Nick Hudson
9 *
10 * Redistribution and use in source and binary forms, with or without
11 * modification, are permitted provided that the following conditions
12 * are met:
13 * 1. Redistributions of source code must retain the above copyright
14 * notice, this list of conditions and the following disclaimer.
15 * 2. Redistributions in binary form must reproduce the above copyright
16 * notice, this list of conditions and the following disclaimer in the
17 * documentation and/or other materials provided with the distribution.
18 *
19 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
20 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
21 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
22 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
23 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
24 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
25 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
26 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
27 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
28 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
29 * POSSIBILITY OF SUCH DAMAGE.
30 */
31
32 #include <sys/cdefs.h>
33 __KERNEL_RCSID(0, "$NetBSD: fdt_mbox.c,v 1.1 2022/03/04 08:19:06 skrll Exp $");
34
35 #include <sys/param.h>
36
37 #include <sys/bus.h>
38 #include <sys/kmem.h>
39 #include <sys/queue.h>
40
41 #include <libfdt.h>
42 #include <dev/fdt/fdtvar.h>
43
44
45 struct fdtbus_mbox_controller {
46 device_t mc_dev;
47 int mc_phandle;
48
49 int mc_cells;
50
51 const struct fdtbus_mbox_controller_func *mc_funcs;
52
53 LIST_ENTRY(fdtbus_mbox_controller) mc_next;
54 };
55
56 static LIST_HEAD(, fdtbus_mbox_controller) fdtbus_mbox_controllers =
57 LIST_HEAD_INITIALIZER(fdtbus_mbox_controllers);
58
59 int
fdtbus_register_mbox_controller(device_t dev,int phandle,const struct fdtbus_mbox_controller_func * funcs)60 fdtbus_register_mbox_controller(device_t dev, int phandle,
61 const struct fdtbus_mbox_controller_func *funcs)
62 {
63 struct fdtbus_mbox_controller *mc;
64
65 uint32_t cells;
66 if (of_getprop_uint32(phandle, "#mbox-cells", &cells) != 0) {
67 aprint_debug_dev(dev, "missing #mbox-cells");
68 return EINVAL;
69 }
70
71 mc = kmem_alloc(sizeof(*mc), KM_SLEEP);
72 mc->mc_dev = dev;
73 mc->mc_phandle = phandle;
74 mc->mc_funcs = funcs;
75 mc->mc_cells = cells;
76
77 LIST_INSERT_HEAD(&fdtbus_mbox_controllers, mc, mc_next);
78
79 return 0;
80 }
81
82 static struct fdtbus_mbox_controller *
fdtbus_mbox_lookup(int phandle)83 fdtbus_mbox_lookup(int phandle)
84 {
85 struct fdtbus_mbox_controller *mc;
86
87 LIST_FOREACH(mc, &fdtbus_mbox_controllers, mc_next) {
88 if (mc->mc_phandle == phandle)
89 return mc;
90 }
91
92 return NULL;
93 }
94
95 struct fdtbus_mbox_channel *
fdtbus_mbox_get_index(int phandle,u_int index,void (* cb)(void *),void * cbarg)96 fdtbus_mbox_get_index(int phandle, u_int index, void (*cb)(void *), void *cbarg)
97 {
98 struct fdtbus_mbox_controller *mc;
99 struct fdtbus_mbox_channel *mbox = NULL;
100 void *mbox_priv = NULL;
101 uint32_t *mboxes = NULL;
102 uint32_t *p;
103 u_int n;
104 int len, resid;
105
106 len = OF_getproplen(phandle, "mboxes");
107 if (len <= 0)
108 return NULL;
109
110 mboxes = kmem_alloc(len, KM_SLEEP);
111 if (OF_getprop(phandle, "mboxes", mboxes, len) != len) {
112 kmem_free(mboxes, len);
113 return NULL;
114 }
115
116 p = mboxes;
117 for (n = 0, resid = len; resid > 0; n++) {
118 const int mc_phandle =
119 fdtbus_get_phandle_from_native(be32toh(p[0]));
120
121 mc = fdtbus_mbox_lookup(mc_phandle);
122 if (mc == NULL)
123 break;
124
125 u_int mbox_cells = mc->mc_cells;
126 if (n == index) {
127 mbox_priv = mc->mc_funcs->mc_acquire(mc->mc_dev,
128 mbox_cells > 0 ? &p[1] : NULL, mbox_cells * 4,
129 cb, cbarg);
130 if (mbox_priv) {
131 mbox = kmem_alloc(sizeof(*mbox), KM_SLEEP);
132 mbox->mb_ctlr = mc;
133 mbox->mb_priv = mbox_priv;
134 }
135 break;
136 }
137 resid -= (mbox_cells + 1) * 4;
138 p += mbox_cells + 1;
139 }
140
141 if (mboxes)
142 kmem_free(mboxes, len);
143
144 return mbox;
145 }
146
147 struct fdtbus_mbox_channel *
fdtbus_mbox_get(int phandle,const char * name,void (* cb)(void *),void * cbarg)148 fdtbus_mbox_get(int phandle, const char *name, void (*cb)(void *), void *cbarg)
149 {
150 u_int index;
151 int err;
152
153 err = fdtbus_get_index(phandle, "mbox-names", name, &index);
154 if (err != 0)
155 return NULL;
156
157 return fdtbus_mbox_get_index(phandle, index, cb, cbarg);
158 }
159
160 void
fdtbus_mbox_put(struct fdtbus_mbox_channel * mbox)161 fdtbus_mbox_put(struct fdtbus_mbox_channel *mbox)
162 {
163 struct fdtbus_mbox_controller *mc = mbox->mb_ctlr;
164
165 mc->mc_funcs->mc_release(mc->mc_dev, mbox->mb_priv);
166 kmem_free(mbox, sizeof(*mbox));
167 }
168
169 int
fdtbus_mbox_send(struct fdtbus_mbox_channel * mbox,const void * data,size_t len)170 fdtbus_mbox_send(struct fdtbus_mbox_channel *mbox, const void *data, size_t len)
171 {
172 struct fdtbus_mbox_controller * const mc = mbox->mb_ctlr;
173
174 return mc->mc_funcs->mc_send(mc->mc_dev, mbox->mb_priv, data, len);
175 }
176
177 int
fdtbus_mbox_recv(struct fdtbus_mbox_channel * mbox,void * data,size_t len)178 fdtbus_mbox_recv(struct fdtbus_mbox_channel *mbox, void *data, size_t len)
179 {
180 struct fdtbus_mbox_controller * const mc = mbox->mb_ctlr;
181
182 return mc->mc_funcs->mc_recv(mc->mc_dev, mbox->mb_priv, data, len);
183 }
184