xref: /freebsd/sys/dev/ofw/ofw_fdt.c (revision d7d962ead0b6e5e8a39202d0590022082bf5bfb6)
1 /*-
2  * SPDX-License-Identifier: BSD-2-Clause-FreeBSD
3  *
4  * Copyright (c) 2009-2010 The FreeBSD Foundation
5  *
6  * This software was developed by Semihalf under sponsorship from
7  * the FreeBSD Foundation.
8  *
9  * Redistribution and use in source and binary forms, with or without
10  * modification, are permitted provided that the following conditions
11  * are met:
12  * 1. Redistributions of source code must retain the above copyright
13  *    notice, this list of conditions and the following disclaimer.
14  * 2. Redistributions in binary form must reproduce the above copyright
15  *    notice, this list of conditions and the following disclaimer in the
16  *    documentation and/or other materials provided with the distribution.
17  *
18  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
19  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
20  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
21  * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
22  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
23  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
24  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
25  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
26  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
27  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
28  * SUCH DAMAGE.
29  */
30 
31 #include <sys/cdefs.h>
32 __FBSDID("$FreeBSD$");
33 
34 #include <sys/param.h>
35 #include <sys/kernel.h>
36 #include <sys/malloc.h>
37 #include <sys/systm.h>
38 
39 #include <contrib/libfdt/libfdt.h>
40 
41 #include <machine/stdarg.h>
42 
43 #include <dev/fdt/fdt_common.h>
44 #include <dev/ofw/ofwvar.h>
45 #include <dev/ofw/openfirm.h>
46 #include <dev/ofw/ofw_bus_subr.h>
47 
48 #include "ofw_if.h"
49 
50 #ifdef DEBUG
51 #define debugf(fmt, args...) do { printf("%s(): ", __func__);	\
52     printf(fmt,##args); } while (0)
53 #else
54 #define debugf(fmt, args...)
55 #endif
56 
57 #if defined(__arm__)
58 #if defined(SOC_MV_ARMADAXP) || defined(SOC_MV_ARMADA38X) || \
59     defined(SOC_MV_DISCOVERY) || defined(SOC_MV_DOVE) || \
60     defined(SOC_MV_FREY) || defined(SOC_MV_KIRKWOOD) || \
61     defined(SOC_MV_LOKIPLUS) || defined(SOC_MV_ORION)
62 #define FDT_MARVELL
63 #endif
64 #endif
65 
66 static int ofw_fdt_init(ofw_t, void *);
67 static phandle_t ofw_fdt_peer(ofw_t, phandle_t);
68 static phandle_t ofw_fdt_child(ofw_t, phandle_t);
69 static phandle_t ofw_fdt_parent(ofw_t, phandle_t);
70 static phandle_t ofw_fdt_instance_to_package(ofw_t, ihandle_t);
71 static ssize_t ofw_fdt_getproplen(ofw_t, phandle_t, const char *);
72 static ssize_t ofw_fdt_getprop(ofw_t, phandle_t, const char *, void *, size_t);
73 static int ofw_fdt_nextprop(ofw_t, phandle_t, const char *, char *, size_t);
74 static int ofw_fdt_setprop(ofw_t, phandle_t, const char *, const void *,
75     size_t);
76 static ssize_t ofw_fdt_canon(ofw_t, const char *, char *, size_t);
77 static phandle_t ofw_fdt_finddevice(ofw_t, const char *);
78 static ssize_t ofw_fdt_instance_to_path(ofw_t, ihandle_t, char *, size_t);
79 static ssize_t ofw_fdt_package_to_path(ofw_t, phandle_t, char *, size_t);
80 static int ofw_fdt_interpret(ofw_t, const char *, int, cell_t *);
81 
82 static ofw_method_t ofw_fdt_methods[] = {
83 	OFWMETHOD(ofw_init,			ofw_fdt_init),
84 	OFWMETHOD(ofw_peer,			ofw_fdt_peer),
85 	OFWMETHOD(ofw_child,			ofw_fdt_child),
86 	OFWMETHOD(ofw_parent,			ofw_fdt_parent),
87 	OFWMETHOD(ofw_instance_to_package,	ofw_fdt_instance_to_package),
88 	OFWMETHOD(ofw_getproplen,		ofw_fdt_getproplen),
89 	OFWMETHOD(ofw_getprop,			ofw_fdt_getprop),
90 	OFWMETHOD(ofw_nextprop,			ofw_fdt_nextprop),
91 	OFWMETHOD(ofw_setprop,			ofw_fdt_setprop),
92 	OFWMETHOD(ofw_canon,			ofw_fdt_canon),
93 	OFWMETHOD(ofw_finddevice,		ofw_fdt_finddevice),
94 	OFWMETHOD(ofw_instance_to_path,		ofw_fdt_instance_to_path),
95 	OFWMETHOD(ofw_package_to_path,		ofw_fdt_package_to_path),
96 	OFWMETHOD(ofw_interpret,		ofw_fdt_interpret),
97 	{ 0, 0 }
98 };
99 
100 static ofw_def_t ofw_fdt = {
101 	OFW_FDT,
102 	ofw_fdt_methods,
103 	0
104 };
105 OFW_DEF(ofw_fdt);
106 
107 #define	FDT_FBSDVER_LEN	16
108 #define	FDT_MODEL_LEN	80
109 #define	FDT_COMPAT_LEN	255
110 
111 static void *fdtp = NULL;
112 static char fdt_model[FDT_MODEL_LEN];
113 static char fdt_compatible[FDT_COMPAT_LEN];
114 static char fdt_fbsd_version[FDT_FBSDVER_LEN];
115 
116 static int
117 sysctl_handle_dtb(SYSCTL_HANDLER_ARGS)
118 {
119 
120         return (sysctl_handle_opaque(oidp, fdtp, fdt_totalsize(fdtp), req));
121 }
122 
123 static void
124 sysctl_register_fdt_oid(void *arg)
125 {
126 
127 	/* If there is no FDT registered, skip adding the sysctl */
128 	if (fdtp == NULL)
129 		return;
130 
131 	SYSCTL_ADD_PROC(NULL, SYSCTL_STATIC_CHILDREN(_hw_fdt), OID_AUTO, "dtb",
132 	    CTLTYPE_OPAQUE | CTLFLAG_RD | CTLFLAG_MPSAFE, NULL, 0,
133 	    sysctl_handle_dtb, "", "Device Tree Blob");
134 	if (fdt_model[0] != '\0')
135 		SYSCTL_ADD_STRING(NULL, SYSCTL_STATIC_CHILDREN(_hw_fdt),
136 		    OID_AUTO, "model", CTLFLAG_RD, fdt_model,
137 		    FDT_MODEL_LEN, "System board model");
138 	if (fdt_compatible[0] != '\0')
139 		SYSCTL_ADD_STRING(NULL, SYSCTL_STATIC_CHILDREN(_hw_fdt),
140 		    OID_AUTO, "compatible", CTLFLAG_RD, fdt_compatible,
141 		    FDT_COMPAT_LEN, "Compatible platforms");
142 	if (fdt_fbsd_version[0] != '\0')
143 		SYSCTL_ADD_STRING(NULL, SYSCTL_STATIC_CHILDREN(_hw_fdt),
144 		    OID_AUTO, "freebsd-version", CTLFLAG_RD, fdt_fbsd_version,
145 		    FDT_FBSDVER_LEN, "FreeBSD DTS branding version");
146 }
147 SYSINIT(dtb_oid, SI_SUB_KMEM, SI_ORDER_ANY, sysctl_register_fdt_oid, NULL);
148 
149 static int
150 ofw_fdt_init(ofw_t ofw, void *data)
151 {
152 	phandle_t root;
153 	ssize_t len;
154 	int err;
155 	int i;
156 
157 	/* Check FDT blob integrity */
158 	if ((err = fdt_check_header(data)) != 0)
159 		return (err);
160 
161 	fdtp = data;
162 	root = ofw_fdt_finddevice(NULL, "/");
163 	len = ofw_fdt_getproplen(NULL, root, "model");
164 	bzero(fdt_model, FDT_MODEL_LEN);
165 	ofw_fdt_getprop(NULL, root, "model", fdt_model, FDT_MODEL_LEN);
166 	len = ofw_fdt_getproplen(NULL, root, "compatible");
167 	bzero(fdt_compatible, FDT_COMPAT_LEN);
168 	ofw_fdt_getprop(NULL, root, "compatible", fdt_compatible, FDT_COMPAT_LEN);
169 	/* Replace the middle '\0' with ' ' */
170 	for (i = 0; i < len - 1; i++)
171 		if (fdt_compatible[i] == '\0')
172 			fdt_compatible[i] = ' ';
173 	if ((len = ofw_fdt_getproplen(NULL, root, "freebsd,dts-version")) > 0) {
174 		bzero(fdt_fbsd_version, FDT_FBSDVER_LEN);
175 		ofw_fdt_getprop(NULL, root, "freebsd,dts-version",
176 		  fdt_fbsd_version, FDT_FBSDVER_LEN);
177 	}
178 	return (0);
179 }
180 
181 /*
182  * Device tree functions.
183  *
184  * We use the offset from fdtp to the node as the 'phandle' in OF interface.
185  *
186  * phandle is a u32 value, therefore we cannot use the pointer to node as
187  * phandle in 64 bit. We also do not use the usual fdt offset as phandle,
188  * as it can be 0, and the OF interface has special meaning for phandle 0.
189  */
190 
191 static phandle_t
192 fdt_offset_phandle(int offset)
193 {
194 	if (offset < 0)
195 		return (0);
196 	return ((phandle_t)offset + fdt_off_dt_struct(fdtp));
197 }
198 
199 static int
200 fdt_phandle_offset(phandle_t p)
201 {
202 	int pint = (int)p;
203 	int dtoff = fdt_off_dt_struct(fdtp);
204 
205 	if (pint < dtoff)
206 		return (-1);
207 	return (pint - dtoff);
208 }
209 
210 /* Return the next sibling of this node or 0. */
211 static phandle_t
212 ofw_fdt_peer(ofw_t ofw, phandle_t node)
213 {
214 	int offset;
215 
216 	if (node == 0) {
217 		/* Find root node */
218 		offset = fdt_path_offset(fdtp, "/");
219 
220 		return (fdt_offset_phandle(offset));
221 	}
222 
223 	offset = fdt_phandle_offset(node);
224 	if (offset < 0)
225 		return (0);
226 	offset = fdt_next_subnode(fdtp, offset);
227 	return (fdt_offset_phandle(offset));
228 }
229 
230 /* Return the first child of this node or 0. */
231 static phandle_t
232 ofw_fdt_child(ofw_t ofw, phandle_t node)
233 {
234 	int offset;
235 
236 	offset = fdt_phandle_offset(node);
237 	if (offset < 0)
238 		return (0);
239 	offset = fdt_first_subnode(fdtp, offset);
240 	return (fdt_offset_phandle(offset));
241 }
242 
243 /* Return the parent of this node or 0. */
244 static phandle_t
245 ofw_fdt_parent(ofw_t ofw, phandle_t node)
246 {
247 	int offset, paroffset;
248 
249 	offset = fdt_phandle_offset(node);
250 	if (offset < 0)
251 		return (0);
252 
253 	paroffset = fdt_parent_offset(fdtp, offset);
254 	return (fdt_offset_phandle(paroffset));
255 }
256 
257 /* Return the package handle that corresponds to an instance handle. */
258 static phandle_t
259 ofw_fdt_instance_to_package(ofw_t ofw, ihandle_t instance)
260 {
261 
262 	/* Where real OF uses ihandles in the tree, FDT uses xref phandles */
263 	return (OF_node_from_xref(instance));
264 }
265 
266 /* Get the length of a property of a package. */
267 static ssize_t
268 ofw_fdt_getproplen(ofw_t ofw, phandle_t package, const char *propname)
269 {
270 	const void *prop;
271 	int offset, len;
272 
273 	offset = fdt_phandle_offset(package);
274 	if (offset < 0)
275 		return (-1);
276 
277 	len = -1;
278 	prop = fdt_getprop(fdtp, offset, propname, &len);
279 
280 	if (prop == NULL && strcmp(propname, "name") == 0) {
281 		/* Emulate the 'name' property */
282 		fdt_get_name(fdtp, offset, &len);
283 		return (len + 1);
284 	}
285 
286 	if (prop == NULL && offset == fdt_path_offset(fdtp, "/chosen")) {
287 		if (strcmp(propname, "fdtbootcpu") == 0)
288 			return (sizeof(cell_t));
289 		if (strcmp(propname, "fdtmemreserv") == 0)
290 			return (sizeof(uint64_t)*2*fdt_num_mem_rsv(fdtp));
291 	}
292 
293 	if (prop == NULL)
294 		return (-1);
295 
296 	return (len);
297 }
298 
299 /* Get the value of a property of a package. */
300 static ssize_t
301 ofw_fdt_getprop(ofw_t ofw, phandle_t package, const char *propname, void *buf,
302     size_t buflen)
303 {
304 	const void *prop;
305 	const char *name;
306 	int len, offset;
307 	uint32_t cpuid;
308 
309 	offset = fdt_phandle_offset(package);
310 	if (offset < 0)
311 		return (-1);
312 
313 	prop = fdt_getprop(fdtp, offset, propname, &len);
314 
315 	if (prop == NULL && strcmp(propname, "name") == 0) {
316 		/* Emulate the 'name' property */
317 		name = fdt_get_name(fdtp, offset, &len);
318 		strncpy(buf, name, buflen);
319 		return (len + 1);
320 	}
321 
322 	if (prop == NULL && offset == fdt_path_offset(fdtp, "/chosen")) {
323 		if (strcmp(propname, "fdtbootcpu") == 0) {
324 			cpuid = cpu_to_fdt32(fdt_boot_cpuid_phys(fdtp));
325 			len = sizeof(cpuid);
326 			prop = &cpuid;
327 		}
328 		if (strcmp(propname, "fdtmemreserv") == 0) {
329 			prop = (char *)fdtp + fdt_off_mem_rsvmap(fdtp);
330 			len = sizeof(uint64_t)*2*fdt_num_mem_rsv(fdtp);
331 		}
332 	}
333 
334 	if (prop == NULL)
335 		return (-1);
336 
337 	bcopy(prop, buf, min(len, buflen));
338 
339 	return (len);
340 }
341 
342 /*
343  * Get the next property of a package. Return values:
344  *  -1: package or previous property does not exist
345  *   0: no more properties
346  *   1: success
347  */
348 static int
349 ofw_fdt_nextprop(ofw_t ofw, phandle_t package, const char *previous, char *buf,
350     size_t size)
351 {
352 	const void *prop;
353 	const char *name;
354 	int offset;
355 
356 	offset = fdt_phandle_offset(package);
357 	if (offset < 0)
358 		return (-1);
359 
360 	if (previous == NULL)
361 		/* Find the first prop in the node */
362 		offset = fdt_first_property_offset(fdtp, offset);
363 	else {
364 		fdt_for_each_property_offset(offset, fdtp, offset) {
365 			prop = fdt_getprop_by_offset(fdtp, offset, &name, NULL);
366 			if (prop == NULL)
367 				return (-1); /* Internal error */
368 			/* Skip until we find 'previous', then bail out */
369 			if (strcmp(name, previous) != 0)
370 				continue;
371 			offset = fdt_next_property_offset(fdtp, offset);
372 			break;
373 		}
374 	}
375 
376 	if (offset < 0)
377 		return (0); /* No properties */
378 
379 	prop = fdt_getprop_by_offset(fdtp, offset, &name, &offset);
380 	if (prop == NULL)
381 		return (-1); /* Internal error */
382 
383 	strncpy(buf, name, size);
384 
385 	return (1);
386 }
387 
388 /* Set the value of a property of a package. */
389 static int
390 ofw_fdt_setprop(ofw_t ofw, phandle_t package, const char *propname,
391     const void *buf, size_t len)
392 {
393 	int offset;
394 
395 	offset = fdt_phandle_offset(package);
396 	if (offset < 0)
397 		return (-1);
398 
399 	if (fdt_setprop_inplace(fdtp, offset, propname, buf, len) != 0)
400 		/* Try to add property, when setting value inplace failed */
401 		return (fdt_setprop(fdtp, offset, propname, buf, len));
402 
403 	return (0);
404 }
405 
406 /* Convert a device specifier to a fully qualified pathname. */
407 static ssize_t
408 ofw_fdt_canon(ofw_t ofw, const char *device, char *buf, size_t len)
409 {
410 
411 	return (-1);
412 }
413 
414 /* Return a package handle for the specified device. */
415 static phandle_t
416 ofw_fdt_finddevice(ofw_t ofw, const char *device)
417 {
418 	int offset;
419 
420 	offset = fdt_path_offset(fdtp, device);
421 	if (offset < 0)
422 		return (-1);
423 	return (fdt_offset_phandle(offset));
424 }
425 
426 /* Return the fully qualified pathname corresponding to an instance. */
427 static ssize_t
428 ofw_fdt_instance_to_path(ofw_t ofw, ihandle_t instance, char *buf, size_t len)
429 {
430 	phandle_t phandle;
431 
432 	phandle = OF_instance_to_package(instance);
433 	if (phandle == -1)
434 		return (-1);
435 
436 	return (OF_package_to_path(phandle, buf, len));
437 }
438 
439 /* Return the fully qualified pathname corresponding to a package. */
440 static ssize_t
441 ofw_fdt_package_to_path(ofw_t ofw, phandle_t package, char *buf, size_t len)
442 {
443 
444 	return (-1);
445 }
446 
447 #if defined(FDT_MARVELL)
448 static int
449 ofw_fdt_fixup(ofw_t ofw)
450 {
451 	char model[FDT_MODEL_LEN];
452 	phandle_t root;
453 	ssize_t len;
454 	int i;
455 
456 	if ((root = ofw_fdt_finddevice(ofw, "/")) == -1)
457 		return (ENODEV);
458 
459 	if ((len = ofw_fdt_getproplen(ofw, root, "model")) <= 0)
460 		return (0);
461 
462 	bzero(model, FDT_MODEL_LEN);
463 	if (ofw_fdt_getprop(ofw, root, "model", model, FDT_MODEL_LEN) <= 0)
464 		return (0);
465 
466 	/*
467 	 * Search fixup table and call handler if appropriate.
468 	 */
469 	for (i = 0; fdt_fixup_table[i].model != NULL; i++) {
470 		if (strncmp(model, fdt_fixup_table[i].model,
471 		    FDT_MODEL_LEN) != 0)
472 			/*
473 			 * Sometimes it's convenient to provide one
474 			 * fixup entry that refers to many boards.
475 			 * To handle this case, simply check if model
476 			 * is compatible parameter
477 			 */
478 			if(!ofw_bus_node_is_compatible(root,
479 			    fdt_fixup_table[i].model))
480 				continue;
481 
482 		if (fdt_fixup_table[i].handler != NULL)
483 			(*fdt_fixup_table[i].handler)(root);
484 	}
485 
486 	return (0);
487 }
488 #endif
489 
490 static int
491 ofw_fdt_interpret(ofw_t ofw, const char *cmd, int nret, cell_t *retvals)
492 {
493 #if defined(FDT_MARVELL)
494 	int rv;
495 
496 	/*
497 	 * Note: FDT does not have the possibility to 'interpret' commands,
498 	 * but we abuse the interface a bit to use it for doing non-standard
499 	 * operations on the device tree blob.
500 	 *
501 	 * Currently the only supported 'command' is to trigger performing
502 	 * fixups.
503 	 */
504 	if (strncmp("perform-fixup", cmd, 13) != 0)
505 		return (0);
506 
507 	rv = ofw_fdt_fixup(ofw);
508 	if (nret > 0)
509 		retvals[0] = rv;
510 
511 	return (rv);
512 #else
513 	return (0);
514 #endif
515 }
516