xref: /netbsd-src/sys/dev/fdt/fdt_subr.c (revision b2a8932dbe9fdfd3d41d60d0a04b9a3ba294763d)
1 /* $NetBSD: fdt_subr.c,v 1.21 2018/03/06 17:40:04 bouyer Exp $ */
2 
3 /*-
4  * Copyright (c) 2015 Jared D. McNeill <jmcneill@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_subr.c,v 1.21 2018/03/06 17:40:04 bouyer Exp $");
31 
32 #include <sys/param.h>
33 #include <sys/bus.h>
34 
35 #include <libfdt.h>
36 #include <dev/fdt/fdtvar.h>
37 
38 static const void *fdt_data;
39 
40 static struct fdt_conslist fdt_console_list =
41     TAILQ_HEAD_INITIALIZER(fdt_console_list);
42 
43 bool
44 fdtbus_set_data(const void *data)
45 {
46 	KASSERT(fdt_data == NULL);
47 	if (fdt_check_header(data) != 0) {
48 		return false;
49 	}
50 	fdt_data = data;
51 	return true;
52 }
53 
54 const void *
55 fdtbus_get_data(void)
56 {
57 	return fdt_data;
58 }
59 
60 int
61 fdtbus_offset2phandle(int offset)
62 {
63 	if (offset < 0)
64 		return 0;
65 
66 	return offset + fdt_off_dt_struct(fdt_data);
67 }
68 
69 int
70 fdtbus_phandle2offset(int phandle)
71 {
72 	const int dtoff = fdt_off_dt_struct(fdt_data);
73 
74 	if (phandle == -1)
75 		phandle = dtoff;
76 
77 	if (phandle < dtoff)
78 		return -1;
79 
80 	return phandle - dtoff;
81 }
82 
83 static bool fdtbus_decoderegprop = true;
84 
85 void
86 fdtbus_set_decoderegprop(bool decode)
87 {
88 	fdtbus_decoderegprop = decode;
89 }
90 
91 static int
92 fdtbus_get_addr_cells(int phandle)
93 {
94 	uint32_t addr_cells;
95 
96 	if (of_getprop_uint32(phandle, "#address-cells", &addr_cells))
97 		addr_cells = 2;
98 
99 	return addr_cells;
100 }
101 
102 static int
103 fdtbus_get_size_cells(int phandle)
104 {
105 	uint32_t size_cells;
106 
107 	if (of_getprop_uint32(phandle, "#size-cells", &size_cells))
108 		size_cells = 0;
109 
110 	return size_cells;
111 }
112 
113 int
114 fdtbus_get_phandle(int phandle, const char *prop)
115 {
116 	u_int phandle_ref;
117 	const u_int *buf;
118 	int len;
119 
120 	buf = fdt_getprop(fdtbus_get_data(),
121 	    fdtbus_phandle2offset(phandle), prop, &len);
122 	if (buf == NULL || len < sizeof(phandle_ref))
123 		return -1;
124 
125 	phandle_ref = be32dec(buf);
126 
127 	return fdtbus_get_phandle_from_native(phandle_ref);
128 }
129 
130 int
131 fdtbus_get_phandle_from_native(int phandle)
132 {
133 	const int off = fdt_node_offset_by_phandle(fdt_data, phandle);
134 	if (off < 0) {
135 		return -1;
136 	}
137 	return fdtbus_offset2phandle(off);
138 }
139 
140 bool
141 fdtbus_get_path(int phandle, char *buf, size_t buflen)
142 {
143 	const int off = fdtbus_phandle2offset(phandle);
144 	if (off < 0) {
145 		return false;
146 	}
147 	if (fdt_get_path(fdt_data, off, buf, (int)buflen) != 0) {
148 		return false;
149 	}
150 	return true;
151 }
152 
153 static uint64_t
154 fdtbus_get_cells(const uint8_t *buf, int cells)
155 {
156 	switch (cells) {
157 	case 0:		return 0;
158 	case 1: 	return be32dec(buf);
159 	case 2: 	return be64dec(buf);
160 	default:	panic("fdtbus_get_cells: bad cells val %d\n", cells);
161 	}
162 }
163 
164 static uint64_t
165 fdtbus_decode_range(int phandle, uint64_t paddr)
166 {
167 	const int parent = OF_parent(phandle);
168 	if (parent == -1)
169 		return paddr;
170 
171 	if (!fdtbus_decoderegprop)
172 		return paddr;
173 
174 	const uint8_t *buf;
175 	int len;
176 
177 	buf = fdt_getprop(fdtbus_get_data(),
178 	    fdtbus_phandle2offset(phandle), "ranges", &len);
179 	if (buf == NULL)
180 		return paddr;
181 
182 	if (len == 0) {
183 		/* pass through to parent */
184 		return fdtbus_decode_range(parent, paddr);
185 	}
186 
187 	const int addr_cells = fdtbus_get_addr_cells(phandle);
188 	const int size_cells = fdtbus_get_size_cells(phandle);
189 	const int paddr_cells = fdtbus_get_addr_cells(OF_parent(parent));
190 	if (addr_cells == -1 || size_cells == -1 || paddr_cells == -1)
191 		return paddr;
192 
193 	while (len > 0) {
194 		uint64_t cba, pba, cl;
195 		cba = fdtbus_get_cells(buf, addr_cells);
196 		buf += addr_cells * 4;
197 		pba = fdtbus_get_cells(buf, paddr_cells);
198 		buf += paddr_cells * 4;
199 		cl = fdtbus_get_cells(buf, size_cells);
200 		buf += size_cells * 4;
201 
202 		if (paddr >= cba && paddr < cba + cl)
203 			return fdtbus_decode_range(parent, pba) + (paddr - cba);
204 
205 		len -= (addr_cells + paddr_cells + size_cells) * 4;
206 	}
207 
208 	/* No mapping found */
209 	return paddr;
210 }
211 
212 int
213 fdtbus_get_reg_byname(int phandle, const char *name, bus_addr_t *paddr,
214     bus_size_t *psize)
215 {
216 	const char *reg_names, *p;
217 	u_int index;
218 	int len, resid;
219 	int error = ENOENT;
220 
221 	reg_names = fdtbus_get_prop(phandle, "reg-names", &len);
222 	if (len <= 0)
223 		return error;
224 
225 	p = reg_names;
226 	for (index = 0, resid = len; resid > 0; index++) {
227 		if (strcmp(p, name) == 0) {
228 			error = fdtbus_get_reg(phandle, index, paddr, psize);
229 			break;
230 		}
231 		resid -= strlen(p);
232 		p += strlen(p) + 1;
233 	}
234 
235 	return error;
236 }
237 
238 int
239 fdtbus_get_reg(int phandle, u_int index, bus_addr_t *paddr, bus_size_t *psize)
240 {
241 	uint64_t addr, size;
242 	int error;
243 
244 	error = fdtbus_get_reg64(phandle, index, &addr, &size);
245 	if (error)
246 		return error;
247 
248 	if (sizeof(bus_addr_t) == 4 && (addr + size) > 0x100000000)
249 		return ERANGE;
250 
251 	if (paddr)
252 		*paddr = (bus_addr_t)addr;
253 	if (psize)
254 		*psize = (bus_size_t)size;
255 
256 	return 0;
257 }
258 
259 int
260 fdtbus_get_reg64(int phandle, u_int index, uint64_t *paddr, uint64_t *psize)
261 {
262 	uint64_t addr, size;
263 	const uint8_t *buf;
264 	int len;
265 
266 	const int addr_cells = fdtbus_get_addr_cells(OF_parent(phandle));
267 	const int size_cells = fdtbus_get_size_cells(OF_parent(phandle));
268 	if (addr_cells == -1 || size_cells == -1)
269 		return EINVAL;
270 
271 	buf = fdt_getprop(fdtbus_get_data(),
272 	    fdtbus_phandle2offset(phandle), "reg", &len);
273 	if (buf == NULL || len <= 0)
274 		return EINVAL;
275 
276 	const u_int reglen = size_cells * 4 + addr_cells * 4;
277 	if (reglen == 0)
278 		return EINVAL;
279 
280 	if (index >= len / reglen)
281 		return ENXIO;
282 
283 	buf += index * reglen;
284 	addr = fdtbus_get_cells(buf, addr_cells);
285 	buf += addr_cells * 4;
286 	size = fdtbus_get_cells(buf, size_cells);
287 
288 	if (paddr) {
289 		*paddr = fdtbus_decode_range(OF_parent(phandle), addr);
290 		const char *name = fdt_get_name(fdtbus_get_data(),
291 		    fdtbus_phandle2offset(phandle), NULL);
292 		aprint_debug("fdt: [%s] decoded addr #%u: %llx -> %llx\n",
293 		    name, index, addr, *paddr);
294 	}
295 	if (psize)
296 		*psize = size;
297 
298 	return 0;
299 }
300 
301 const struct fdt_console *
302 fdtbus_get_console(void)
303 {
304 	static const struct fdt_console_info *booted_console = NULL;
305 
306 	if (booted_console == NULL) {
307 		__link_set_decl(fdt_consoles, struct fdt_console_info);
308 		struct fdt_console_info * const *info;
309 		const struct fdt_console_info *best_info = NULL;
310 		const int phandle = fdtbus_get_stdout_phandle();
311 		int best_match = 0;
312 
313 		__link_set_foreach(info, fdt_consoles) {
314 			const int match = (*info)->ops->match(phandle);
315 			if (match > best_match) {
316 				best_match = match;
317 				best_info = *info;
318 			}
319 		}
320 
321 		booted_console = best_info;
322 	}
323 
324 	return booted_console == NULL ? NULL : booted_console->ops;
325 }
326 
327 const char *
328 fdtbus_get_stdout_path(void)
329 {
330 	const char *prop;
331 
332 	const int off = fdt_path_offset(fdtbus_get_data(), "/chosen");
333 	if (off < 0)
334 		return NULL;
335 
336 	prop = fdt_getprop(fdtbus_get_data(), off, "stdout-path", NULL);
337 	if (prop != NULL)
338 		return prop;
339 
340 	/* If the stdout-path property is not found, assume serial0 */
341 	return "serial0:115200n8";
342 }
343 
344 int
345 fdtbus_get_stdout_phandle(void)
346 {
347 	const char *prop, *p;
348 	int off, len;
349 
350 	prop = fdtbus_get_stdout_path();
351 	if (prop == NULL)
352 		return -1;
353 
354 	p = strchr(prop, ':');
355 	len = p == NULL ? strlen(prop) : (p - prop);
356 	if (*prop != '/') {
357 		/* Alias */
358 		prop = fdt_get_alias_namelen(fdtbus_get_data(), prop, len);
359 		if (prop == NULL)
360 			return -1;
361 		len = strlen(prop);
362 	}
363 	off = fdt_path_offset_namelen(fdtbus_get_data(), prop, len);
364 	if (off < 0)
365 		return -1;
366 
367 	return fdtbus_offset2phandle(off);
368 }
369 
370 int
371 fdtbus_get_stdout_speed(void)
372 {
373 	const char *prop, *p;
374 
375 	prop = fdtbus_get_stdout_path();
376 	if (prop == NULL)
377 		return -1;
378 
379 	p = strchr(prop, ':');
380 	if (p == NULL)
381 		return -1;
382 
383 	return (int)strtoul(p + 1, NULL, 10);
384 }
385 
386 tcflag_t
387 fdtbus_get_stdout_flags(void)
388 {
389 	const char *prop, *p;
390 	tcflag_t flags = TTYDEF_CFLAG;
391 	char *ep;
392 
393 	prop = fdtbus_get_stdout_path();
394 	if (prop == NULL)
395 		return flags;
396 
397 	p = strchr(prop, ':');
398 	if (p == NULL)
399 		return flags;
400 
401 	ep = NULL;
402 	(void)strtoul(p + 1, &ep, 10);
403 	if (ep == NULL)
404 		return flags;
405 
406 	/* <baud>{<parity>{<bits>{<flow>}}} */
407 	while (*ep) {
408 		switch (*ep) {
409 		/* parity */
410 		case 'n':	flags &= ~(PARENB|PARODD); break;
411 		case 'e':	flags &= ~PARODD; flags |= PARENB; break;
412 		case 'o':	flags |= (PARENB|PARODD); break;
413 		/* bits */
414 		case '5':	flags &= ~CSIZE; flags |= CS5; break;
415 		case '6':	flags &= ~CSIZE; flags |= CS6; break;
416 		case '7':	flags &= ~CSIZE; flags |= CS7; break;
417 		case '8':	flags &= ~CSIZE; flags |= CS8; break;
418 		/* flow */
419 		case 'r':	flags |= CRTSCTS; break;
420 		}
421 		ep++;
422 	}
423 
424 	return flags;
425 }
426 
427 bool
428 fdtbus_status_okay(int phandle)
429 {
430 	const int off = fdtbus_phandle2offset(phandle);
431 
432 	const char *prop = fdt_getprop(fdtbus_get_data(), off, "status", NULL);
433 	if (prop == NULL)
434 		return true;
435 
436 	return strncmp(prop, "ok", 2) == 0;
437 }
438 
439 const void *
440 fdtbus_get_prop(int phandle, const char *prop, int *plen)
441 {
442 	const int off = fdtbus_phandle2offset(phandle);
443 
444 	return fdt_getprop(fdtbus_get_data(), off, prop, plen);
445 }
446 
447 const char *
448 fdtbus_get_string(int phandle, const char *prop)
449 {
450 	const int off = fdtbus_phandle2offset(phandle);
451 
452 	if (strcmp(prop, "name") == 0)
453 		return fdt_get_name(fdtbus_get_data(), off, NULL);
454 	else
455 		return fdt_getprop(fdtbus_get_data(), off, prop, NULL);
456 }
457 
458 const char *
459 fdtbus_get_string_index(int phandle, const char *prop, u_int index)
460 {
461 	const char *names, *name;
462 	int len, cur;
463 
464 	if ((len = OF_getproplen(phandle, prop)) < 0)
465 		return NULL;
466 
467 	names = fdtbus_get_string(phandle, prop);
468 
469 	for (name = names, cur = 0; len > 0;
470 	     len -= strlen(name) + 1, name += strlen(name) + 1, cur++) {
471 		if (index == cur)
472 			return name;
473 	}
474 
475 	return NULL;
476 }
477