xref: /netbsd-src/sys/dev/fdt/fdt_subr.c (revision 796c32c94f6e154afc9de0f63da35c91bb739b45)
1 /* $NetBSD: fdt_subr.c,v 1.19 2017/09/19 22:55:49 jmcneill 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 1.19 2017/09/19 22:55:49 jmcneill 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 
84 static int
85 fdtbus_get_addr_cells(int phandle)
86 {
87 	uint32_t addr_cells;
88 
89 	if (of_getprop_uint32(phandle, "#address-cells", &addr_cells))
90 		addr_cells = 2;
91 
92 	return addr_cells;
93 }
94 
95 static int
96 fdtbus_get_size_cells(int phandle)
97 {
98 	uint32_t size_cells;
99 
100 	if (of_getprop_uint32(phandle, "#size-cells", &size_cells))
101 		size_cells = 0;
102 
103 	return size_cells;
104 }
105 
106 int
107 fdtbus_get_phandle(int phandle, const char *prop)
108 {
109 	u_int phandle_ref;
110 	const u_int *buf;
111 	int len;
112 
113 	buf = fdt_getprop(fdtbus_get_data(),
114 	    fdtbus_phandle2offset(phandle), prop, &len);
115 	if (buf == NULL || len < sizeof(phandle_ref))
116 		return -1;
117 
118 	phandle_ref = be32dec(buf);
119 
120 	return fdtbus_get_phandle_from_native(phandle_ref);
121 }
122 
123 int
124 fdtbus_get_phandle_from_native(int phandle)
125 {
126 	const int off = fdt_node_offset_by_phandle(fdt_data, phandle);
127 	if (off < 0) {
128 		return -1;
129 	}
130 	return fdtbus_offset2phandle(off);
131 }
132 
133 bool
134 fdtbus_get_path(int phandle, char *buf, size_t buflen)
135 {
136 	const int off = fdtbus_phandle2offset(phandle);
137 	if (off < 0) {
138 		return false;
139 	}
140 	if (fdt_get_path(fdt_data, off, buf, (int)buflen) != 0) {
141 		return false;
142 	}
143 	return true;
144 }
145 
146 static uint64_t
147 fdtbus_get_cells(const uint8_t *buf, int cells)
148 {
149 	switch (cells) {
150 	case 0:		return 0;
151 	case 1: 	return be32dec(buf);
152 	case 2: 	return be64dec(buf);
153 	default:	panic("fdtbus_get_cells: bad cells val %d\n", cells);
154 	}
155 }
156 
157 static uint64_t
158 fdtbus_decode_range(int phandle, uint64_t paddr)
159 {
160 	const int parent = OF_parent(phandle);
161 	if (parent == -1)
162 		return paddr;
163 	const uint8_t *buf;
164 	int len;
165 
166 	buf = fdt_getprop(fdtbus_get_data(),
167 	    fdtbus_phandle2offset(phandle), "ranges", &len);
168 	if (buf == NULL)
169 		return paddr;
170 
171 	if (len == 0) {
172 		/* pass through to parent */
173 		return fdtbus_decode_range(parent, paddr);
174 	}
175 
176 	const int addr_cells = fdtbus_get_addr_cells(phandle);
177 	const int size_cells = fdtbus_get_size_cells(phandle);
178 	const int paddr_cells = fdtbus_get_addr_cells(OF_parent(parent));
179 	if (addr_cells == -1 || size_cells == -1 || paddr_cells == -1)
180 		return paddr;
181 
182 	while (len > 0) {
183 		uint64_t cba, pba, cl;
184 		cba = fdtbus_get_cells(buf, addr_cells);
185 		buf += addr_cells * 4;
186 		pba = fdtbus_get_cells(buf, paddr_cells);
187 		buf += paddr_cells * 4;
188 		cl = fdtbus_get_cells(buf, size_cells);
189 		buf += size_cells * 4;
190 
191 		if (paddr >= cba && paddr < cba + cl)
192 			return fdtbus_decode_range(parent, pba) + (paddr - cba);
193 
194 		len -= (addr_cells + paddr_cells + size_cells) * 4;
195 	}
196 
197 	/* No mapping found */
198 	return paddr;
199 }
200 
201 int
202 fdtbus_get_reg_byname(int phandle, const char *name, bus_addr_t *paddr,
203     bus_size_t *psize)
204 {
205 	const char *reg_names, *p;
206 	u_int index;
207 	int len, resid;
208 	int error = ENOENT;
209 
210 	reg_names = fdtbus_get_prop(phandle, "reg-names", &len);
211 	if (len <= 0)
212 		return error;
213 
214 	p = reg_names;
215 	for (index = 0, resid = len; resid > 0; index++) {
216 		if (strcmp(p, name) == 0) {
217 			error = fdtbus_get_reg(phandle, index, paddr, psize);
218 			break;
219 		}
220 		resid -= strlen(p);
221 		p += strlen(p) + 1;
222 	}
223 
224 	return error;
225 }
226 
227 int
228 fdtbus_get_reg(int phandle, u_int index, bus_addr_t *paddr, bus_size_t *psize)
229 {
230 	uint64_t addr, size;
231 	int error;
232 
233 	error = fdtbus_get_reg64(phandle, index, &addr, &size);
234 	if (error)
235 		return error;
236 
237 	if (sizeof(bus_addr_t) == 4 && (addr + size) > 0x100000000)
238 		return ERANGE;
239 
240 	if (paddr)
241 		*paddr = (bus_addr_t)addr;
242 	if (psize)
243 		*psize = (bus_size_t)size;
244 
245 	return 0;
246 }
247 
248 int
249 fdtbus_get_reg64(int phandle, u_int index, uint64_t *paddr, uint64_t *psize)
250 {
251 	uint64_t addr, size;
252 	const uint8_t *buf;
253 	int len;
254 
255 	const int addr_cells = fdtbus_get_addr_cells(OF_parent(phandle));
256 	const int size_cells = fdtbus_get_size_cells(OF_parent(phandle));
257 	if (addr_cells == -1 || size_cells == -1)
258 		return EINVAL;
259 
260 	buf = fdt_getprop(fdtbus_get_data(),
261 	    fdtbus_phandle2offset(phandle), "reg", &len);
262 	if (buf == NULL || len <= 0)
263 		return EINVAL;
264 
265 	const u_int reglen = size_cells * 4 + addr_cells * 4;
266 	if (reglen == 0)
267 		return EINVAL;
268 
269 	if (index >= len / reglen)
270 		return ENXIO;
271 
272 	buf += index * reglen;
273 	addr = fdtbus_get_cells(buf, addr_cells);
274 	buf += addr_cells * 4;
275 	size = fdtbus_get_cells(buf, size_cells);
276 
277 	if (paddr) {
278 		*paddr = fdtbus_decode_range(OF_parent(phandle), addr);
279 		const char *name = fdt_get_name(fdtbus_get_data(),
280 		    fdtbus_phandle2offset(phandle), NULL);
281 		aprint_debug("fdt: [%s] decoded addr #%u: %llx -> %llx\n",
282 		    name, index, addr, *paddr);
283 	}
284 	if (psize)
285 		*psize = size;
286 
287 	return 0;
288 }
289 
290 const struct fdt_console *
291 fdtbus_get_console(void)
292 {
293 	static const struct fdt_console_info *booted_console = NULL;
294 
295 	if (booted_console == NULL) {
296 		__link_set_decl(fdt_consoles, struct fdt_console_info);
297 		struct fdt_console_info * const *info;
298 		const struct fdt_console_info *best_info = NULL;
299 		const int phandle = fdtbus_get_stdout_phandle();
300 		int best_match = 0;
301 
302 		__link_set_foreach(info, fdt_consoles) {
303 			const int match = (*info)->ops->match(phandle);
304 			if (match > best_match) {
305 				best_match = match;
306 				best_info = *info;
307 			}
308 		}
309 
310 		booted_console = best_info;
311 	}
312 
313 	return booted_console == NULL ? NULL : booted_console->ops;
314 }
315 
316 const char *
317 fdtbus_get_stdout_path(void)
318 {
319 	const char *prop;
320 
321 	const int off = fdt_path_offset(fdtbus_get_data(), "/chosen");
322 	if (off < 0)
323 		return NULL;
324 
325 	prop = fdt_getprop(fdtbus_get_data(), off, "stdout-path", NULL);
326 	if (prop != NULL)
327 		return prop;
328 
329 	/* If the stdout-path property is not found, assume serial0 */
330 	return "serial0:115200n8";
331 }
332 
333 int
334 fdtbus_get_stdout_phandle(void)
335 {
336 	const char *prop, *p;
337 	int off, len;
338 
339 	prop = fdtbus_get_stdout_path();
340 	if (prop == NULL)
341 		return -1;
342 
343 	p = strchr(prop, ':');
344 	len = p == NULL ? strlen(prop) : (p - prop);
345 	if (*prop != '/') {
346 		/* Alias */
347 		prop = fdt_get_alias_namelen(fdtbus_get_data(), prop, len);
348 		if (prop == NULL)
349 			return -1;
350 		len = strlen(prop);
351 	}
352 	off = fdt_path_offset_namelen(fdtbus_get_data(), prop, len);
353 	if (off < 0)
354 		return -1;
355 
356 	return fdtbus_offset2phandle(off);
357 }
358 
359 int
360 fdtbus_get_stdout_speed(void)
361 {
362 	const char *prop, *p;
363 
364 	prop = fdtbus_get_stdout_path();
365 	if (prop == NULL)
366 		return -1;
367 
368 	p = strchr(prop, ':');
369 	if (p == NULL)
370 		return -1;
371 
372 	return (int)strtoul(p + 1, NULL, 10);
373 }
374 
375 tcflag_t
376 fdtbus_get_stdout_flags(void)
377 {
378 	const char *prop, *p;
379 	tcflag_t flags = TTYDEF_CFLAG;
380 	char *ep;
381 
382 	prop = fdtbus_get_stdout_path();
383 	if (prop == NULL)
384 		return flags;
385 
386 	p = strchr(prop, ':');
387 	if (p == NULL)
388 		return flags;
389 
390 	ep = NULL;
391 	(void)strtoul(p + 1, &ep, 10);
392 	if (ep == NULL)
393 		return flags;
394 
395 	/* <baud>{<parity>{<bits>{<flow>}}} */
396 	while (*ep) {
397 		switch (*ep) {
398 		/* parity */
399 		case 'n':	flags &= ~(PARENB|PARODD); break;
400 		case 'e':	flags &= ~PARODD; flags |= PARENB; break;
401 		case 'o':	flags |= (PARENB|PARODD); break;
402 		/* bits */
403 		case '5':	flags &= ~CSIZE; flags |= CS5; break;
404 		case '6':	flags &= ~CSIZE; flags |= CS6; break;
405 		case '7':	flags &= ~CSIZE; flags |= CS7; break;
406 		case '8':	flags &= ~CSIZE; flags |= CS8; break;
407 		/* flow */
408 		case 'r':	flags |= CRTSCTS; break;
409 		}
410 		ep++;
411 	}
412 
413 	return flags;
414 }
415 
416 bool
417 fdtbus_status_okay(int phandle)
418 {
419 	const int off = fdtbus_phandle2offset(phandle);
420 
421 	const char *prop = fdt_getprop(fdtbus_get_data(), off, "status", NULL);
422 	if (prop == NULL)
423 		return true;
424 
425 	return strncmp(prop, "ok", 2) == 0;
426 }
427 
428 const void *
429 fdtbus_get_prop(int phandle, const char *prop, int *plen)
430 {
431 	const int off = fdtbus_phandle2offset(phandle);
432 
433 	return fdt_getprop(fdtbus_get_data(), off, prop, plen);
434 }
435 
436 const char *
437 fdtbus_get_string(int phandle, const char *prop)
438 {
439 	const int off = fdtbus_phandle2offset(phandle);
440 
441 	if (strcmp(prop, "name") == 0)
442 		return fdt_get_name(fdtbus_get_data(), off, NULL);
443 	else
444 		return fdt_getprop(fdtbus_get_data(), off, prop, NULL);
445 }
446 
447 const char *
448 fdtbus_get_string_index(int phandle, const char *prop, u_int index)
449 {
450 	const char *names, *name;
451 	int len, cur;
452 
453 	if ((len = OF_getproplen(phandle, prop)) < 0)
454 		return NULL;
455 
456 	names = fdtbus_get_string(phandle, prop);
457 
458 	for (name = names, cur = 0; len > 0;
459 	     name += strlen(name) + 1, cur++) {
460 		if (index == cur)
461 			return name;
462 	}
463 
464 	return NULL;
465 }
466