fdt_intr.c revision 1.9 1 /* $NetBSD: fdt_intr.c,v 1.9 2017/06/02 00:55:26 jmcneill Exp $ */
2
3 /*-
4 * Copyright (c) 2015 Jared D. 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 1.9 2017/06/02 00:55:26 jmcneill Exp $");
31
32 #include <sys/param.h>
33 #include <sys/bus.h>
34 #include <sys/kmem.h>
35
36 #include <libfdt.h>
37 #include <dev/fdt/fdtvar.h>
38
39 struct fdtbus_interrupt_controller {
40 device_t ic_dev;
41 int ic_phandle;
42 const struct fdtbus_interrupt_controller_func *ic_funcs;
43
44 struct fdtbus_interrupt_controller *ic_next;
45 };
46
47 static struct fdtbus_interrupt_controller *fdtbus_ic = NULL;
48
49 static bool has_interrupt_map(int phandle);
50 static u_int *get_specifier_by_index(int phandle, int pindex, u_int *spec);
51 static u_int *get_specifier_from_map(int phandle, u_int *spec, u_int spec_len, int *piphandle);
52
53 static int
54 fdtbus_get_interrupt_parent(int phandle)
55 {
56 u_int interrupt_parent;
57
58 while (phandle >= 0) {
59 if (of_getprop_uint32(phandle, "interrupt-parent",
60 &interrupt_parent) == 0) {
61 break;
62 }
63 if (phandle == 0) {
64 return -1;
65 }
66 phandle = OF_parent(phandle);
67 }
68 if (phandle < 0) {
69 return -1;
70 }
71
72 const void *data = fdtbus_get_data();
73 const int off = fdt_node_offset_by_phandle(data, interrupt_parent);
74 if (off < 0) {
75 return -1;
76 }
77
78 return fdtbus_offset2phandle(off);
79 }
80
81 static struct fdtbus_interrupt_controller *
82 fdtbus_get_interrupt_controller_ic(int phandle)
83 {
84 struct fdtbus_interrupt_controller * ic;
85 for (ic = fdtbus_ic; ic; ic = ic->ic_next) {
86 if (ic->ic_phandle == phandle) {
87 return ic;
88 }
89 }
90 return NULL;
91 }
92
93 static struct fdtbus_interrupt_controller *
94 fdtbus_get_interrupt_controller(int phandle)
95 {
96 const int ic_phandle = fdtbus_get_interrupt_parent(phandle);
97 if (ic_phandle < 0) {
98 return NULL;
99 }
100
101 return fdtbus_get_interrupt_controller_ic(ic_phandle);
102 }
103
104 int
105 fdtbus_register_interrupt_controller(device_t dev, int phandle,
106 const struct fdtbus_interrupt_controller_func *funcs)
107 {
108 struct fdtbus_interrupt_controller *ic;
109
110 ic = kmem_alloc(sizeof(*ic), KM_SLEEP);
111 ic->ic_dev = dev;
112 ic->ic_phandle = phandle;
113 ic->ic_funcs = funcs;
114
115 ic->ic_next = fdtbus_ic;
116 fdtbus_ic = ic;
117
118 return 0;
119 }
120
121 void *
122 fdtbus_intr_establish(int phandle, u_int index, int ipl, int flags,
123 int (*func)(void *), void *arg)
124 {
125 struct fdtbus_interrupt_controller *ic;
126 int ihandle = phandle;
127 u_int *specifier;
128 u_int spec_length;
129
130 specifier = get_specifier_by_index(phandle, index, &spec_length);
131 if (has_interrupt_map(phandle))
132 specifier = get_specifier_from_map(phandle, specifier,
133 spec_length, &ihandle);
134
135 ic = fdtbus_get_interrupt_controller(ihandle);
136 if (ic == NULL)
137 return NULL;
138
139 return ic->ic_funcs->establish(ic->ic_dev, specifier,
140 ipl, flags, func, arg);
141 }
142
143 void
144 fdtbus_intr_disestablish(int phandle, void *ih)
145 {
146 struct fdtbus_interrupt_controller *ic;
147
148 ic = fdtbus_get_interrupt_controller(phandle);
149 KASSERT(ic != NULL);
150
151 return ic->ic_funcs->disestablish(ic->ic_dev, ih);
152 }
153
154 bool
155 fdtbus_intr_str(int phandle, u_int index, char *buf, size_t buflen)
156 {
157 struct fdtbus_interrupt_controller *ic;
158 int ihandle = phandle;
159 u_int *specifier;
160 u_int spec_length;
161
162 specifier = get_specifier_by_index(phandle, index, &spec_length);
163 if (has_interrupt_map(phandle))
164 specifier = get_specifier_from_map(phandle, specifier,
165 spec_length, &ihandle);
166
167 ic = fdtbus_get_interrupt_controller(ihandle);
168 if (ic == NULL)
169 return false;
170
171 return ic->ic_funcs->intrstr(ic->ic_dev, specifier, buf, buflen);
172 }
173
174 static int
175 find_interrupt_map(int phandle)
176 {
177 while (phandle > 0) {
178 if (of_hasprop(phandle, "interrupt-map"))
179 return phandle;
180 phandle = OF_parent(phandle);
181 }
182 return -1;
183 }
184
185 static int
186 find_address_cells(int phandle)
187 {
188 uint32_t cells;
189
190 if (of_getprop_uint32(phandle, "#address-cells", &cells) != 0)
191 cells = 2;
192
193 return cells;
194 }
195
196 static int
197 find_interrupt_cells(int phandle)
198 {
199 uint32_t cells;
200
201 while (phandle > 0) {
202 if (of_getprop_uint32(phandle, "#interrupt-cells", &cells) == 0)
203 return cells;
204 phandle = OF_parent(phandle);
205 }
206 return 0;
207 }
208
209 static bool
210 has_interrupt_map(int phandle)
211 {
212 return find_interrupt_map(OF_parent(phandle)) != -1;
213 }
214
215 static u_int *
216 get_specifier_from_map(int phandle, u_int *specifier, u_int spec_length, int *piphandle)
217 {
218 u_int *result = NULL;
219
220 const int nexus_phandle = find_interrupt_map(phandle);
221
222 int len = OF_getproplen(nexus_phandle, "interrupt-map");
223 if (len <= 0) {
224 printf("%s: no interrupt-map.\n", __func__);
225 return NULL;
226 }
227 int resid = len;
228 char *data = kmem_alloc(len, KM_SLEEP);
229 len = OF_getprop(nexus_phandle, "interrupt-map", data, len);
230 if (len <= 0) {
231 printf("%s: can't get property interrupt-map.\n", __func__);
232 goto done;
233 }
234
235 /* child unit address: #address-cells prop of child bus node */
236 const int cua_cells = find_address_cells(nexus_phandle);
237 /* child interrupt specifier: #interrupt-cells of the nexus node */
238 const int cis_cells = find_interrupt_cells(nexus_phandle);
239
240 /* Offset (in cells) from map entry to child unit address specifier */
241 const u_int cua_off = 0;
242 /* Offset (in cells) from map entry to child interrupt specifier */
243 const u_int cis_off = cua_off + cua_cells;
244 /* Offset (in cells) from map entry to interrupt parent phandle */
245 const u_int ip_off = cis_off + cis_cells;
246 /* Offset (in cells) from map entry to parent unit specifier */
247 const u_int pus_off = ip_off + 1;
248
249 #ifdef FDT_INTR_DEBUG
250 printf("cua_cells: %d, cis_cells: %d, ip_off = %d\n", cua_cells, cis_cells, ip_off);
251 printf("searching for interrupt in map:");
252 for (int i = 0; i < spec_length; i++)
253 printf(" %08x", specifier[i]);
254 printf("\n");
255 #endif
256
257 u_int *p = (u_int *)data;
258 while (resid > 0) {
259 /* Interrupt parent phandle */
260 const u_int iparent = fdtbus_get_phandle_from_native(be32toh(p[ip_off]));
261
262 /* parent unit specifier: #address-cells of the interrupt parent */
263 const u_int pus_cells = find_address_cells(iparent);
264 /* parent interrupt specifier: #interrupt-cells of the interrupt parent */
265 const u_int pis_cells = find_interrupt_cells(iparent);
266
267 /* Offset (in cells) from map entry to parent interrupt specifier */
268 const u_int pis_off = pus_off + pus_cells;
269
270 if (cis_cells == spec_length && memcmp(&p[cis_off], specifier, spec_length * 4) == 0) {
271 const int slen = pus_cells + pis_cells;
272 #ifdef FDT_INTR_DEBUG
273 printf(" intr map match iparent %08x slen %d:", iparent, slen);
274 for (int i = 0; i < slen; i++)
275 printf(" %08x", p[pus_off + i]);
276 printf("\n");
277 #endif
278 result = kmem_alloc(slen, KM_SLEEP);
279 memcpy(result, &p[pus_off], slen * 4);
280 *piphandle = iparent;
281 goto done;
282 }
283 /* Determine the length of the entry and skip that many
284 * 32 bit words
285 */
286 const u_int reclen = pis_off + pis_cells;
287 resid -= reclen * sizeof(u_int);
288 p += reclen;
289 }
290
291 done:
292 kmem_free(data, len);
293 return result;
294 }
295
296 static u_int *
297 get_specifier_by_index(int phandle, int pindex, u_int *spec_length)
298 {
299 u_int *specifiers;
300 u_int *specifier;
301 int interrupt_parent, interrupt_cells, len;
302
303 interrupt_parent = fdtbus_get_interrupt_parent(phandle);
304 if (interrupt_parent <= 0)
305 return NULL;
306
307 interrupt_cells = find_interrupt_cells(interrupt_parent);
308 if (interrupt_cells <= 0)
309 return NULL;
310
311 len = OF_getproplen(phandle, "interrupts");
312 if (len <= 0)
313 return NULL;
314
315 const u_int nintr = len / interrupt_cells;
316
317 if (pindex >= nintr)
318 return NULL;
319
320 specifiers = kmem_alloc(len, KM_SLEEP);
321
322 if (OF_getprop(phandle, "interrupts", specifiers, len) != len) {
323 kmem_free(specifiers, len);
324 return NULL;
325 }
326 specifier = kmem_alloc(interrupt_cells * sizeof(u_int), KM_SLEEP);
327 *spec_length = interrupt_cells;
328 for (int i = 0; i < interrupt_cells; i++)
329 specifier[i] = specifiers[pindex * interrupt_cells + i];
330 kmem_free(specifiers, len);
331 return specifier;
332 }
333