1 /*-
2 * SPDX-License-Identifier: BSD-2-Clause
3 *
4 * Copyright (c) 2017 Kyle Evans <kevans@FreeBSD.org>
5 *
6 * Redistribution and use in source and binary forms, with or without
7 * modification, are permitted provided that the following conditions
8 * are met:
9 * 1. Redistributions of source code must retain the above copyright
10 * notice, this list of conditions and the following disclaimer.
11 * 2. Redistributions in binary form must reproduce the above copyright
12 * notice, this list of conditions and the following disclaimer in the
13 * documentation and/or other materials provided with the distribution.
14 *
15 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
16 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
17 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
18 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
19 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
20 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
21 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
22 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
23 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
24 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
25 * SUCH DAMAGE.
26 */
27
28 /*
29 * This is a generic syscon driver, whose purpose is to provide access to
30 * various unrelated bits packed in a single register space. It is usually used
31 * as a fallback to more specific driver, but works well enough for simple
32 * access.
33 */
34
35 #include <sys/cdefs.h>
36 #include "opt_platform.h"
37
38 #include <sys/param.h>
39 #include <sys/systm.h>
40 #include <sys/bus.h>
41 #include <sys/kernel.h>
42 #include <sys/kobj.h>
43 #include <sys/lock.h>
44 #include <sys/malloc.h>
45 #include <sys/module.h>
46 #include <sys/rman.h>
47 #include <sys/sx.h>
48 #include <sys/queue.h>
49
50 #include <machine/bus.h>
51
52 #ifdef FDT
53 #include <dev/ofw/ofw_bus.h>
54 #include <dev/ofw/ofw_bus_subr.h>
55 #endif
56
57 #include "syscon_if.h"
58 #include "syscon.h"
59
60 /*
61 * Syscon interface details
62 */
63 typedef TAILQ_HEAD(syscon_list, syscon) syscon_list_t;
64
65 /*
66 * Declarations
67 */
68 static int syscon_method_init(struct syscon *syscon);
69 static int syscon_method_uninit(struct syscon *syscon);
70 static uint32_t syscon_method_read_4(struct syscon *syscon, bus_size_t offset);
71 static int syscon_method_write_4(struct syscon *syscon, bus_size_t offset,
72 uint32_t val);
73 static int syscon_method_modify_4(struct syscon *syscon, bus_size_t offset,
74 uint32_t clear_bits, uint32_t set_bits);
75
76
77 MALLOC_DEFINE(M_SYSCON, "syscon", "Syscon driver");
78
79 static syscon_list_t syscon_list = TAILQ_HEAD_INITIALIZER(syscon_list);
80 static struct sx syscon_topo_lock;
81 SX_SYSINIT(syscon_topology, &syscon_topo_lock, "Syscon topology lock");
82
83 /*
84 * Syscon methods.
85 */
86 static syscon_method_t syscon_methods[] = {
87 SYSCONMETHOD(syscon_init, syscon_method_init),
88 SYSCONMETHOD(syscon_uninit, syscon_method_uninit),
89 SYSCONMETHOD(syscon_read_4, syscon_method_read_4),
90 SYSCONMETHOD(syscon_write_4, syscon_method_write_4),
91 SYSCONMETHOD(syscon_modify_4, syscon_method_modify_4),
92
93 SYSCONMETHOD_END
94 };
95 DEFINE_CLASS_0(syscon, syscon_class, syscon_methods, 0);
96
97 #define SYSCON_TOPO_SLOCK() sx_slock(&syscon_topo_lock)
98 #define SYSCON_TOPO_XLOCK() sx_xlock(&syscon_topo_lock)
99 #define SYSCON_TOPO_UNLOCK() sx_unlock(&syscon_topo_lock)
100 #define SYSCON_TOPO_ASSERT() sx_assert(&syscon_topo_lock, SA_LOCKED)
101 #define SYSCON_TOPO_XASSERT() sx_assert(&syscon_topo_lock, SA_XLOCKED)
102
103 /*
104 * Default syscon methods for base class.
105 */
106 static int
syscon_method_init(struct syscon * syscon)107 syscon_method_init(struct syscon *syscon)
108 {
109
110 return (0);
111 };
112
113 static int
syscon_method_uninit(struct syscon * syscon)114 syscon_method_uninit(struct syscon *syscon)
115 {
116
117 return (0);
118 };
119
120 void *
syscon_get_softc(struct syscon * syscon)121 syscon_get_softc(struct syscon *syscon)
122 {
123
124 return (syscon->softc);
125 };
126
127 static uint32_t
syscon_method_read_4(struct syscon * syscon,bus_size_t offset)128 syscon_method_read_4(struct syscon *syscon, bus_size_t offset)
129 {
130 uint32_t val;
131
132 SYSCON_DEVICE_LOCK(syscon->pdev);
133 val = SYSCON_UNLOCKED_READ_4(syscon, offset);
134 SYSCON_DEVICE_UNLOCK(syscon->pdev);
135 return(val);
136 }
137
138 static int
syscon_method_write_4(struct syscon * syscon,bus_size_t offset,uint32_t val)139 syscon_method_write_4(struct syscon *syscon, bus_size_t offset, uint32_t val)
140 {
141 int rv;
142
143 SYSCON_DEVICE_LOCK(syscon->pdev);
144 rv = SYSCON_UNLOCKED_WRITE_4(syscon, offset, val);
145 SYSCON_DEVICE_UNLOCK(syscon->pdev);
146 return(rv);
147 }
148
149 static int
syscon_method_modify_4(struct syscon * syscon,bus_size_t offset,uint32_t clear_bits,uint32_t set_bits)150 syscon_method_modify_4(struct syscon *syscon, bus_size_t offset,
151 uint32_t clear_bits, uint32_t set_bits)
152 {
153 int rv;
154
155 SYSCON_DEVICE_LOCK(syscon->pdev);
156 rv = SYSCON_UNLOCKED_MODIFY_4(syscon, offset, clear_bits, set_bits);
157 SYSCON_DEVICE_UNLOCK(syscon->pdev);
158 return(rv);
159 }
160 /*
161 * Create and initialize syscon object, but do not register it.
162 */
163 struct syscon *
syscon_create(device_t pdev,syscon_class_t syscon_class)164 syscon_create(device_t pdev, syscon_class_t syscon_class)
165 {
166 struct syscon *syscon;
167
168 /* Create object and initialize it. */
169 syscon = malloc(sizeof(struct syscon), M_SYSCON,
170 M_WAITOK | M_ZERO);
171 kobj_init((kobj_t)syscon, (kobj_class_t)syscon_class);
172
173 /* Allocate softc if required. */
174 if (syscon_class->size > 0)
175 syscon->softc = malloc(syscon_class->size, M_SYSCON,
176 M_WAITOK | M_ZERO);
177
178 /* Rest of init. */
179 syscon->pdev = pdev;
180 return (syscon);
181 }
182
183 /* Register syscon object. */
184 struct syscon *
syscon_register(struct syscon * syscon)185 syscon_register(struct syscon *syscon)
186 {
187 int rv;
188
189 #ifdef FDT
190 if (syscon->ofw_node <= 0)
191 syscon->ofw_node = ofw_bus_get_node(syscon->pdev);
192 if (syscon->ofw_node <= 0)
193 return (NULL);
194 #endif
195
196 rv = SYSCON_INIT(syscon);
197 if (rv != 0) {
198 printf("SYSCON_INIT failed: %d\n", rv);
199 return (NULL);
200 }
201
202 #ifdef FDT
203 OF_device_register_xref(OF_xref_from_node(syscon->ofw_node),
204 syscon->pdev);
205 #endif
206 SYSCON_TOPO_XLOCK();
207 TAILQ_INSERT_TAIL(&syscon_list, syscon, syscon_link);
208 SYSCON_TOPO_UNLOCK();
209 return (syscon);
210 }
211
212 int
syscon_unregister(struct syscon * syscon)213 syscon_unregister(struct syscon *syscon)
214 {
215
216 SYSCON_TOPO_XLOCK();
217 TAILQ_REMOVE(&syscon_list, syscon, syscon_link);
218 SYSCON_TOPO_UNLOCK();
219 #ifdef FDT
220 OF_device_register_xref(OF_xref_from_node(syscon->ofw_node), NULL);
221 #endif
222 return (SYSCON_UNINIT(syscon));
223 }
224
225 /**
226 * Provider methods
227 */
228 #ifdef FDT
229 static struct syscon *
syscon_find_by_ofw_node(phandle_t node)230 syscon_find_by_ofw_node(phandle_t node)
231 {
232 struct syscon *entry;
233
234 SYSCON_TOPO_ASSERT();
235
236 TAILQ_FOREACH(entry, &syscon_list, syscon_link) {
237 if (entry->ofw_node == node)
238 return (entry);
239 }
240
241 return (NULL);
242 }
243
244 struct syscon *
syscon_create_ofw_node(device_t pdev,syscon_class_t syscon_class,phandle_t node)245 syscon_create_ofw_node(device_t pdev, syscon_class_t syscon_class,
246 phandle_t node)
247 {
248 struct syscon *syscon;
249
250 syscon = syscon_create(pdev, syscon_class);
251 if (syscon == NULL)
252 return (NULL);
253 syscon->ofw_node = node;
254 if (syscon_register(syscon) == NULL)
255 return (NULL);
256 return (syscon);
257 }
258
259 phandle_t
syscon_get_ofw_node(struct syscon * syscon)260 syscon_get_ofw_node(struct syscon *syscon)
261 {
262
263 return (syscon->ofw_node);
264 }
265
266 int
syscon_get_by_ofw_node(device_t cdev,phandle_t node,struct syscon ** syscon)267 syscon_get_by_ofw_node(device_t cdev, phandle_t node, struct syscon **syscon)
268 {
269
270 SYSCON_TOPO_SLOCK();
271 *syscon = syscon_find_by_ofw_node(node);
272 if (*syscon == NULL) {
273 SYSCON_TOPO_UNLOCK();
274 device_printf(cdev, "Failed to find syscon node\n");
275 return (ENODEV);
276 }
277 SYSCON_TOPO_UNLOCK();
278 return (0);
279 }
280
281 int
syscon_get_by_ofw_property(device_t cdev,phandle_t cnode,char * name,struct syscon ** syscon)282 syscon_get_by_ofw_property(device_t cdev, phandle_t cnode, char *name,
283 struct syscon **syscon)
284 {
285 pcell_t *cells;
286 int ncells;
287
288 if (cnode <= 0)
289 cnode = ofw_bus_get_node(cdev);
290 if (cnode <= 0) {
291 device_printf(cdev,
292 "%s called on not ofw based device\n", __func__);
293 return (ENXIO);
294 }
295 ncells = OF_getencprop_alloc_multi(cnode, name, sizeof(pcell_t),
296 (void **)&cells);
297 if (ncells < 1)
298 return (ENOENT);
299
300 /* Translate to syscon node. */
301 SYSCON_TOPO_SLOCK();
302 *syscon = syscon_find_by_ofw_node(OF_node_from_xref(cells[0]));
303 if (*syscon == NULL) {
304 SYSCON_TOPO_UNLOCK();
305 device_printf(cdev, "Failed to find syscon node\n");
306 OF_prop_free(cells);
307 return (ENODEV);
308 }
309 SYSCON_TOPO_UNLOCK();
310 OF_prop_free(cells);
311 return (0);
312 }
313 #endif
314