xref: /netbsd-src/sys/dev/fdt/fdt_subr.c (revision 7c192b2a5e1093666e67801684f930ef49b3b363)
1 /* $NetBSD: fdt_subr.c,v 1.17 2017/07/19 20:18:07 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 1.17 2017/07/19 20:18:07 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(int phandle, u_int index, bus_addr_t *paddr, bus_size_t *psize)
203 {
204 	uint64_t addr, size;
205 	int error;
206 
207 	error = fdtbus_get_reg64(phandle, index, &addr, &size);
208 	if (error)
209 		return error;
210 
211 	if (sizeof(bus_addr_t) == 4 && (addr + size) > 0x100000000)
212 		return ERANGE;
213 
214 	if (paddr)
215 		*paddr = (bus_addr_t)addr;
216 	if (psize)
217 		*psize = (bus_size_t)size;
218 
219 	return 0;
220 }
221 
222 int
223 fdtbus_get_reg64(int phandle, u_int index, uint64_t *paddr, uint64_t *psize)
224 {
225 	uint64_t addr, size;
226 	const uint8_t *buf;
227 	int len;
228 
229 	const int addr_cells = fdtbus_get_addr_cells(OF_parent(phandle));
230 	const int size_cells = fdtbus_get_size_cells(OF_parent(phandle));
231 	if (addr_cells == -1 || size_cells == -1)
232 		return EINVAL;
233 
234 	buf = fdt_getprop(fdtbus_get_data(),
235 	    fdtbus_phandle2offset(phandle), "reg", &len);
236 	if (buf == NULL || len <= 0)
237 		return EINVAL;
238 
239 	const u_int reglen = size_cells * 4 + addr_cells * 4;
240 	if (reglen == 0)
241 		return EINVAL;
242 
243 	if (index >= len / reglen)
244 		return ENXIO;
245 
246 	buf += index * reglen;
247 	addr = fdtbus_get_cells(buf, addr_cells);
248 	buf += addr_cells * 4;
249 	size = fdtbus_get_cells(buf, size_cells);
250 
251 	if (paddr) {
252 		*paddr = fdtbus_decode_range(OF_parent(phandle), addr);
253 		const char *name = fdt_get_name(fdtbus_get_data(),
254 		    fdtbus_phandle2offset(phandle), NULL);
255 		aprint_debug("fdt: [%s] decoded addr #%u: %llx -> %llx\n",
256 		    name, index, addr, *paddr);
257 	}
258 	if (psize)
259 		*psize = size;
260 
261 	return 0;
262 }
263 
264 const struct fdt_console *
265 fdtbus_get_console(void)
266 {
267 	static const struct fdt_console_info *booted_console = NULL;
268 
269 	if (booted_console == NULL) {
270 		__link_set_decl(fdt_consoles, struct fdt_console_info);
271 		struct fdt_console_info * const *info;
272 		const struct fdt_console_info *best_info = NULL;
273 		const int phandle = fdtbus_get_stdout_phandle();
274 		int best_match = 0;
275 
276 		__link_set_foreach(info, fdt_consoles) {
277 			const int match = (*info)->ops->match(phandle);
278 			if (match > best_match) {
279 				best_match = match;
280 				best_info = *info;
281 			}
282 		}
283 
284 		booted_console = best_info;
285 	}
286 
287 	return booted_console == NULL ? NULL : booted_console->ops;
288 }
289 
290 const char *
291 fdtbus_get_stdout_path(void)
292 {
293 	const char *prop;
294 
295 	const int off = fdt_path_offset(fdtbus_get_data(), "/chosen");
296 	if (off < 0)
297 		return NULL;
298 
299 	prop = fdt_getprop(fdtbus_get_data(), off, "stdout-path", NULL);
300 	if (prop != NULL)
301 		return prop;
302 
303 	/* If the stdout-path property is not found, assume serial0 */
304 	return "serial0:115200n8";
305 }
306 
307 int
308 fdtbus_get_stdout_phandle(void)
309 {
310 	const char *prop, *p;
311 	int off, len;
312 
313 	prop = fdtbus_get_stdout_path();
314 	if (prop == NULL)
315 		return -1;
316 
317 	p = strchr(prop, ':');
318 	len = p == NULL ? strlen(prop) : (p - prop);
319 	if (*prop != '/') {
320 		/* Alias */
321 		prop = fdt_get_alias_namelen(fdtbus_get_data(), prop, len);
322 		if (prop == NULL)
323 			return -1;
324 		len = strlen(prop);
325 	}
326 	off = fdt_path_offset_namelen(fdtbus_get_data(), prop, len);
327 	if (off < 0)
328 		return -1;
329 
330 	return fdtbus_offset2phandle(off);
331 }
332 
333 int
334 fdtbus_get_stdout_speed(void)
335 {
336 	const char *prop, *p;
337 
338 	prop = fdtbus_get_stdout_path();
339 	if (prop == NULL)
340 		return -1;
341 
342 	p = strchr(prop, ':');
343 	if (p == NULL)
344 		return -1;
345 
346 	return (int)strtoul(p + 1, NULL, 10);
347 }
348 
349 tcflag_t
350 fdtbus_get_stdout_flags(void)
351 {
352 	const char *prop, *p;
353 	tcflag_t flags = TTYDEF_CFLAG;
354 	char *ep;
355 
356 	prop = fdtbus_get_stdout_path();
357 	if (prop == NULL)
358 		return flags;
359 
360 	p = strchr(prop, ':');
361 	if (p == NULL)
362 		return flags;
363 
364 	ep = NULL;
365 	(void)strtoul(p + 1, &ep, 10);
366 	if (ep == NULL)
367 		return flags;
368 
369 	/* <baud>{<parity>{<bits>{<flow>}}} */
370 	while (*ep) {
371 		switch (*ep) {
372 		/* parity */
373 		case 'n':	flags &= ~(PARENB|PARODD); break;
374 		case 'e':	flags &= ~PARODD; flags |= PARENB; break;
375 		case 'o':	flags |= (PARENB|PARODD); break;
376 		/* bits */
377 		case '5':	flags &= ~CSIZE; flags |= CS5; break;
378 		case '6':	flags &= ~CSIZE; flags |= CS6; break;
379 		case '7':	flags &= ~CSIZE; flags |= CS7; break;
380 		case '8':	flags &= ~CSIZE; flags |= CS8; break;
381 		/* flow */
382 		case 'r':	flags |= CRTSCTS; break;
383 		}
384 		ep++;
385 	}
386 
387 	return flags;
388 }
389 
390 bool
391 fdtbus_status_okay(int phandle)
392 {
393 	const int off = fdtbus_phandle2offset(phandle);
394 
395 	const char *prop = fdt_getprop(fdtbus_get_data(), off, "status", NULL);
396 	if (prop == NULL)
397 		return true;
398 
399 	return strncmp(prop, "ok", 2) == 0;
400 }
401 
402 const void *
403 fdtbus_get_prop(int phandle, const char *prop, int *plen)
404 {
405 	const int off = fdtbus_phandle2offset(phandle);
406 
407 	return fdt_getprop(fdtbus_get_data(), off, prop, plen);
408 }
409 
410 const char *
411 fdtbus_get_string(int phandle, const char *prop)
412 {
413 	const int off = fdtbus_phandle2offset(phandle);
414 
415 	return fdt_getprop(fdtbus_get_data(), off, prop, NULL);
416 }
417 
418 const char *
419 fdtbus_get_string_index(int phandle, const char *prop, u_int index)
420 {
421 	const char *names, *name;
422 	int len, cur;
423 
424 	if ((len = OF_getproplen(phandle, prop)) < 0)
425 		return NULL;
426 
427 	names = fdtbus_get_string(phandle, prop);
428 
429 	for (name = names, cur = 0; len > 0;
430 	     name += strlen(name) + 1, cur++) {
431 		if (index == cur)
432 			return name;
433 	}
434 
435 	return NULL;
436 }
437