fdt_intr.c revision 1.14 1 /* $NetBSD: fdt_intr.c,v 1.14 2018/07/02 16:06:50 jmcneill Exp $ */
2
3 /*-
4 * Copyright (c) 2015-2018 Jared McNeill <jmcneill (at) invisible.ca>
5 * All rights reserved.
6 *
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
9 * are met:
10 * 1. Redistributions of source code must retain the above copyright
11 * notice, this list of conditions and the following disclaimer.
12 * 2. Redistributions in binary form must reproduce the above copyright
13 * notice, this list of conditions and the following disclaimer in the
14 * documentation and/or other materials provided with the distribution.
15 *
16 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
17 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
18 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
19 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
20 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
21 * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
22 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
23 * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
24 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
25 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
26 * SUCH DAMAGE.
27 */
28
29 #include <sys/cdefs.h>
30 __KERNEL_RCSID(0, "$NetBSD: fdt_intr.c,v 1.14 2018/07/02 16:06:50 jmcneill Exp $");
31
32 #include <sys/param.h>
33 #include <sys/bus.h>
34 #include <sys/kmem.h>
35 #include <sys/queue.h>
36
37 #include <libfdt.h>
38 #include <dev/fdt/fdtvar.h>
39
40 struct fdtbus_interrupt_controller {
41 device_t ic_dev;
42 int ic_phandle;
43 const struct fdtbus_interrupt_controller_func *ic_funcs;
44
45 LIST_ENTRY(fdtbus_interrupt_controller) ic_next;
46 };
47
48 static LIST_HEAD(, fdtbus_interrupt_controller) fdtbus_interrupt_controllers =
49 LIST_HEAD_INITIALIZER(fdtbus_interrupt_controllers);
50
51 struct fdtbus_interrupt_cookie {
52 struct fdtbus_interrupt_controller *c_ic;
53 void *c_ih;
54 };
55
56 static u_int * get_specifier_by_index(int, int, int *);
57 static u_int * get_specifier_from_map(int, const u_int *, int *);
58
59 static int
60 fdtbus_get_interrupt_parent(int phandle)
61 {
62 int iparent = phandle;
63
64 do {
65 if (of_hasprop(iparent, "interrupt-parent"))
66 return fdtbus_get_phandle(iparent, "interrupt-parent");
67 else if (of_hasprop(iparent, "interrupt-controller"))
68 return iparent;
69 else if (of_hasprop(iparent, "interrupt-map"))
70 return iparent;
71 iparent = OF_parent(iparent);
72 } while (iparent > 0);
73
74 return 0;
75 }
76
77 static struct fdtbus_interrupt_controller *
78 fdtbus_get_interrupt_controller(int phandle)
79 {
80 struct fdtbus_interrupt_controller * ic;
81 LIST_FOREACH(ic, &fdtbus_interrupt_controllers, ic_next) {
82 if (ic->ic_phandle == phandle)
83 return ic;
84 }
85 return NULL;
86 }
87
88 int
89 fdtbus_register_interrupt_controller(device_t dev, int phandle,
90 const struct fdtbus_interrupt_controller_func *funcs)
91 {
92 struct fdtbus_interrupt_controller *ic;
93
94 ic = kmem_alloc(sizeof(*ic), KM_SLEEP);
95 ic->ic_dev = dev;
96 ic->ic_phandle = phandle;
97 ic->ic_funcs = funcs;
98
99 LIST_INSERT_HEAD(&fdtbus_interrupt_controllers, ic, ic_next);
100
101 return 0;
102 }
103
104 void *
105 fdtbus_intr_establish(int phandle, u_int index, int ipl, int flags,
106 int (*func)(void *), void *arg)
107 {
108 struct fdtbus_interrupt_controller *ic;
109 struct fdtbus_interrupt_cookie *c = NULL;
110 u_int *specifier;
111 int ihandle;
112 void *ih;
113
114 specifier = get_specifier_by_index(phandle, index, &ihandle);
115 if (specifier == NULL)
116 return NULL;
117
118 ic = fdtbus_get_interrupt_controller(ihandle);
119 if (ic == NULL)
120 return NULL;
121
122 ih = ic->ic_funcs->establish(ic->ic_dev, specifier,
123 ipl, flags, func, arg);
124 if (ih != NULL) {
125 c = kmem_alloc(sizeof(*c), KM_SLEEP);
126 c->c_ic = ic;
127 c->c_ih = ih;
128 }
129
130 return c;
131 }
132
133 void
134 fdtbus_intr_disestablish(int phandle, void *cookie)
135 {
136 struct fdtbus_interrupt_cookie *c = cookie;
137 struct fdtbus_interrupt_controller *ic = c->c_ic;
138 void *ih = c->c_ih;
139
140 return ic->ic_funcs->disestablish(ic->ic_dev, ih);
141 }
142
143 bool
144 fdtbus_intr_str(int phandle, u_int index, char *buf, size_t buflen)
145 {
146 struct fdtbus_interrupt_controller *ic;
147 u_int *specifier;
148 int ihandle;
149
150 specifier = get_specifier_by_index(phandle, index, &ihandle);
151
152 ic = fdtbus_get_interrupt_controller(ihandle);
153 if (ic == NULL)
154 return false;
155
156 return ic->ic_funcs->intrstr(ic->ic_dev, specifier, buf, buflen);
157 }
158
159 static int
160 find_address_cells(int phandle)
161 {
162 uint32_t cells;
163
164 if (of_getprop_uint32(phandle, "#address-cells", &cells) != 0)
165 cells = 2;
166
167 return cells;
168 }
169
170 static int
171 find_interrupt_cells(int phandle)
172 {
173 uint32_t cells;
174
175 while (phandle > 0) {
176 if (of_getprop_uint32(phandle, "#interrupt-cells", &cells) == 0)
177 return cells;
178 phandle = OF_parent(phandle);
179 }
180 return 0;
181 }
182
183 static u_int *
184 get_specifier_from_map(int phandle, const u_int *interrupt_spec, int *piphandle)
185 {
186 u_int *result = NULL;
187 int len, resid;
188
189 const u_int *data = fdtbus_get_prop(phandle, "interrupt-map", &len);
190 if (data == NULL || len <= 0)
191 return NULL;
192 resid = len;
193
194 /* child unit address: #address-cells prop of child bus node */
195 const int cua_cells = find_address_cells(phandle);
196 /* child interrupt specifier: #interrupt-cells of the nexus node */
197 const int cis_cells = find_interrupt_cells(phandle);
198
199 /* Offset (in cells) from map entry to child unit address specifier */
200 const u_int cua_off = 0;
201 /* Offset (in cells) from map entry to child interrupt specifier */
202 const u_int cis_off = cua_off + cua_cells;
203 /* Offset (in cells) from map entry to interrupt parent phandle */
204 const u_int ip_off = cis_off + cis_cells;
205 /* Offset (in cells) from map entry to parent unit specifier */
206 const u_int pus_off = ip_off + 1;
207
208 const u_int *p = (const u_int *)data;
209 while (resid > 0) {
210 /* Interrupt parent phandle */
211 const u_int iparent = fdtbus_get_phandle_from_native(be32toh(p[ip_off]));
212
213 /* parent unit specifier: #address-cells of the interrupt parent */
214 const u_int pus_cells = find_address_cells(iparent);
215 /* parent interrupt specifier: #interrupt-cells of the interrupt parent */
216 const u_int pis_cells = find_interrupt_cells(iparent);
217
218 /* Offset (in cells) from map entry to parent interrupt specifier */
219 const u_int pis_off = pus_off + pus_cells;
220
221 #ifdef FDT_INTR_DEBUG
222 printf(" intr map (len %d):", pis_off + pis_cells);
223 for (int i = 0; i < pis_off + pis_cells; i++)
224 printf(" %08x", p[i]);
225 printf("\n");
226 #endif
227
228 if (memcmp(&p[cis_off], interrupt_spec, cis_cells * 4) == 0) {
229 const int slen = pus_cells + pis_cells;
230 #ifdef FDT_INTR_DEBUG
231 printf(" intr map match iparent %08x slen %d:", iparent, slen);
232 for (int i = 0; i < slen; i++)
233 printf(" %08x", p[pus_off + i]);
234 printf("\n");
235 #endif
236 result = kmem_alloc(slen, KM_SLEEP);
237 memcpy(result, &p[pus_off], slen * 4);
238 *piphandle = iparent;
239 goto done;
240 }
241 /* Determine the length of the entry and skip that many
242 * 32 bit words
243 */
244 const u_int reclen = pis_off + pis_cells;
245 resid -= reclen * sizeof(u_int);
246 p += reclen;
247 }
248
249 done:
250 return result;
251 }
252
253 static u_int *
254 get_specifier_by_index(int phandle, int pindex, int *piphandle)
255 {
256 const u_int *node_specifier;
257 u_int *specifier;
258 int interrupt_parent, interrupt_cells, len;
259
260 interrupt_parent = fdtbus_get_interrupt_parent(phandle);
261 if (interrupt_parent <= 0)
262 return NULL;
263
264 node_specifier = fdtbus_get_prop(phandle, "interrupts", &len);
265 if (node_specifier == NULL)
266 return NULL;
267
268 interrupt_cells = find_interrupt_cells(interrupt_parent);
269 if (interrupt_cells <= 0)
270 return NULL;
271
272 const u_int spec_length = len / 4;
273 const u_int nintr = spec_length / interrupt_cells;
274 if (pindex >= nintr)
275 return NULL;
276
277 node_specifier += (interrupt_cells * pindex);
278
279 if (of_hasprop(interrupt_parent, "interrupt-map"))
280 return get_specifier_from_map(interrupt_parent, node_specifier, piphandle);
281
282 specifier = kmem_alloc(interrupt_cells * sizeof(u_int), KM_SLEEP);
283 memcpy(specifier, node_specifier, interrupt_cells * 4);
284
285 *piphandle = interrupt_parent;
286
287 return specifier;
288 }
289