1/*-
2 * Copyright (c) 2009-2010 The FreeBSD Foundation
3 * All rights reserved.
4 *
5 * This software was developed by Semihalf under sponsorship from
6 * the FreeBSD Foundation.
7 *
8 * Redistribution and use in source and binary forms, with or without
9 * modification, are permitted provided that the following conditions
10 * are met:
11 * 1. Redistributions of source code must retain the above copyright
12 *    notice, this list of conditions and the following disclaimer.
13 * 2. Redistributions in binary form must reproduce the above copyright
14 *    notice, this list of conditions and the following disclaimer in the
15 *    documentation and/or other materials provided with the distribution.
16 *
17 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
18 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
21 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
22 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
23 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
24 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
25 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
26 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
27 * SUCH DAMAGE.
28 */
29
30#include <sys/cdefs.h>
31__FBSDID("$FreeBSD$");
32
33#include <sys/param.h>
34#include <sys/kernel.h>
35#include <sys/malloc.h>
36#include <sys/systm.h>
37
38#include <contrib/libfdt/libfdt.h>
39
40#include <machine/stdarg.h>
41
42#include <dev/fdt/fdt_common.h>
43#include <dev/ofw/ofwvar.h>
44#include <dev/ofw/openfirm.h>
45
46#include "ofw_if.h"
47
48#ifdef DEBUG
49#define debugf(fmt, args...) do { printf("%s(): ", __func__);	\
50    printf(fmt,##args); } while (0)
51#else
52#define debugf(fmt, args...)
53#endif
54
55static int ofw_fdt_init(ofw_t, void *);
56static phandle_t ofw_fdt_peer(ofw_t, phandle_t);
57static phandle_t ofw_fdt_child(ofw_t, phandle_t);
58static phandle_t ofw_fdt_parent(ofw_t, phandle_t);
59static phandle_t ofw_fdt_instance_to_package(ofw_t, ihandle_t);
60static ssize_t ofw_fdt_getproplen(ofw_t, phandle_t, const char *);
61static ssize_t ofw_fdt_getprop(ofw_t, phandle_t, const char *, void *, size_t);
62static int ofw_fdt_nextprop(ofw_t, phandle_t, const char *, char *, size_t);
63static int ofw_fdt_setprop(ofw_t, phandle_t, const char *, const void *,
64    size_t);
65static ssize_t ofw_fdt_canon(ofw_t, const char *, char *, size_t);
66static phandle_t ofw_fdt_finddevice(ofw_t, const char *);
67static ssize_t ofw_fdt_instance_to_path(ofw_t, ihandle_t, char *, size_t);
68static ssize_t ofw_fdt_package_to_path(ofw_t, phandle_t, char *, size_t);
69static int ofw_fdt_interpret(ofw_t, const char *, int, cell_t *);
70
71static ofw_method_t ofw_fdt_methods[] = {
72	OFWMETHOD(ofw_init,			ofw_fdt_init),
73	OFWMETHOD(ofw_peer,			ofw_fdt_peer),
74	OFWMETHOD(ofw_child,			ofw_fdt_child),
75	OFWMETHOD(ofw_parent,			ofw_fdt_parent),
76	OFWMETHOD(ofw_instance_to_package,	ofw_fdt_instance_to_package),
77	OFWMETHOD(ofw_getproplen,		ofw_fdt_getproplen),
78	OFWMETHOD(ofw_getprop,			ofw_fdt_getprop),
79	OFWMETHOD(ofw_nextprop,			ofw_fdt_nextprop),
80	OFWMETHOD(ofw_setprop,			ofw_fdt_setprop),
81	OFWMETHOD(ofw_canon,			ofw_fdt_canon),
82	OFWMETHOD(ofw_finddevice,		ofw_fdt_finddevice),
83	OFWMETHOD(ofw_instance_to_path,		ofw_fdt_instance_to_path),
84	OFWMETHOD(ofw_package_to_path,		ofw_fdt_package_to_path),
85	OFWMETHOD(ofw_interpret,		ofw_fdt_interpret),
86	{ 0, 0 }
87};
88
89static ofw_def_t ofw_fdt = {
90	OFW_FDT,
91	ofw_fdt_methods,
92	0
93};
94OFW_DEF(ofw_fdt);
95
96static void *fdtp = NULL;
97
98static int
99ofw_fdt_init(ofw_t ofw, void *data)
100{
101	int err;
102
103	/* Check FDT blob integrity */
104	if ((err = fdt_check_header(data)) != 0)
105		return (err);
106
107	fdtp = data;
108	return (0);
109}
110
111/*
112 * Device tree functions.
113 *
114 * We use the offset from fdtp to the node as the 'phandle' in OF interface.
115 *
116 * phandle is a u32 value, therefore we cannot use the pointer to node as
117 * phandle in 64 bit. We also do not use the usual fdt offset as phandle,
118 * as it can be 0, and the OF interface has special meaning for phandle 0.
119 */
120
121static phandle_t
122fdt_offset_phandle(int offset)
123{
124	if (offset < 0)
125		return (0);
126	return ((phandle_t)offset + fdt_off_dt_struct(fdtp));
127}
128
129static int
130fdt_phandle_offset(phandle_t p)
131{
132	int pint = (int)p;
133	int dtoff = fdt_off_dt_struct(fdtp);
134
135	if (pint < dtoff)
136		return (-1);
137	return (pint - dtoff);
138}
139
140/* Return the next sibling of this node or 0. */
141static phandle_t
142ofw_fdt_peer(ofw_t ofw, phandle_t node)
143{
144	int depth, offset;
145
146	if (node == 0) {
147		/* Find root node */
148		offset = fdt_path_offset(fdtp, "/");
149
150		return (fdt_offset_phandle(offset));
151	}
152
153	offset = fdt_phandle_offset(node);
154	if (offset < 0)
155		return (0);
156
157	for (depth = 1, offset = fdt_next_node(fdtp, offset, &depth);
158	    offset >= 0;
159	    offset = fdt_next_node(fdtp, offset, &depth)) {
160		if (depth < 0)
161			return (0);
162		if (depth == 1)
163			return (fdt_offset_phandle(offset));
164	}
165
166	return (0);
167}
168
169/* Return the first child of this node or 0. */
170static phandle_t
171ofw_fdt_child(ofw_t ofw, phandle_t node)
172{
173	int depth, offset;
174
175	offset = fdt_phandle_offset(node);
176	if (offset < 0)
177		return (0);
178
179	for (depth = 0, offset = fdt_next_node(fdtp, offset, &depth);
180	    (offset >= 0) && (depth > 0);
181	    offset = fdt_next_node(fdtp, offset, &depth)) {
182		if (depth < 0)
183			return (0);
184		if (depth == 1)
185			return (fdt_offset_phandle(offset));
186	}
187
188	return (0);
189}
190
191/* Return the parent of this node or 0. */
192static phandle_t
193ofw_fdt_parent(ofw_t ofw, phandle_t node)
194{
195	int offset, paroffset;
196
197	offset = fdt_phandle_offset(node);
198	if (offset < 0)
199		return (0);
200
201	paroffset = fdt_parent_offset(fdtp, offset);
202	return (fdt_offset_phandle(paroffset));
203}
204
205/* Return the package handle that corresponds to an instance handle. */
206static phandle_t
207ofw_fdt_instance_to_package(ofw_t ofw, ihandle_t instance)
208{
209
210	/* Where real OF uses ihandles in the tree, FDT uses xref phandles */
211	return (OF_node_from_xref(instance));
212}
213
214/* Get the length of a property of a package. */
215static ssize_t
216ofw_fdt_getproplen(ofw_t ofw, phandle_t package, const char *propname)
217{
218	const struct fdt_property *prop;
219	int offset, len;
220
221	offset = fdt_phandle_offset(package);
222	if (offset < 0)
223		return (-1);
224
225	if (strcmp(propname, "name") == 0) {
226		/* Emulate the 'name' property */
227		fdt_get_name(fdtp, offset, &len);
228		return (len + 1);
229	}
230
231	len = -1;
232	prop = fdt_get_property(fdtp, offset, propname, &len);
233
234	return (len);
235}
236
237/* Get the value of a property of a package. */
238static ssize_t
239ofw_fdt_getprop(ofw_t ofw, phandle_t package, const char *propname, void *buf,
240    size_t buflen)
241{
242	const void *prop;
243	const char *name;
244	int len, offset;
245
246	offset = fdt_phandle_offset(package);
247	if (offset < 0)
248		return (-1);
249
250	if (strcmp(propname, "name") == 0) {
251		/* Emulate the 'name' property */
252		name = fdt_get_name(fdtp, offset, &len);
253		strncpy(buf, name, buflen);
254		if (len + 1 > buflen)
255			len = buflen;
256		return (len + 1);
257	}
258
259	prop = fdt_getprop(fdtp, offset, propname, &len);
260	if (prop == NULL)
261		return (-1);
262
263	if (len > buflen)
264		len = buflen;
265	bcopy(prop, buf, len);
266	return (len);
267}
268
269/*
270 * Get the next property of a package. Return values:
271 *  -1: package or previous property does not exist
272 *   0: no more properties
273 *   1: success
274 */
275static int
276ofw_fdt_nextprop(ofw_t ofw, phandle_t package, const char *previous, char *buf,
277    size_t size)
278{
279	const struct fdt_property *prop;
280	const char *name;
281	int offset;
282
283	offset = fdt_phandle_offset(package);
284	if (offset < 0)
285		return (-1);
286
287	/* Find the first prop in the node */
288	offset = fdt_first_property_offset(fdtp, offset);
289	if (offset < 0)
290		return (0); /* No properties */
291
292	if (previous != NULL) {
293		while (offset >= 0) {
294			prop = fdt_get_property_by_offset(fdtp, offset, NULL);
295			if (prop == NULL)
296				return (-1); /* Internal error */
297
298			offset = fdt_next_property_offset(fdtp, offset);
299			if (offset < 0)
300				return (0); /* No more properties */
301
302			/* Check if the last one was the one we wanted */
303			name = fdt_string(fdtp, fdt32_to_cpu(prop->nameoff));
304			if (strcmp(name, previous) == 0)
305				break;
306		}
307	}
308
309	prop = fdt_get_property_by_offset(fdtp, offset, &offset);
310	if (prop == NULL)
311		return (-1); /* Internal error */
312
313	strncpy(buf, fdt_string(fdtp, fdt32_to_cpu(prop->nameoff)), size);
314
315	return (1);
316}
317
318/* Set the value of a property of a package. */
319static int
320ofw_fdt_setprop(ofw_t ofw, phandle_t package, const char *propname,
321    const void *buf, size_t len)
322{
323	int offset;
324
325	offset = fdt_phandle_offset(package);
326	if (offset < 0)
327		return (-1);
328
329	return (fdt_setprop_inplace(fdtp, offset, propname, buf, len));
330}
331
332/* Convert a device specifier to a fully qualified pathname. */
333static ssize_t
334ofw_fdt_canon(ofw_t ofw, const char *device, char *buf, size_t len)
335{
336
337	return (-1);
338}
339
340/* Return a package handle for the specified device. */
341static phandle_t
342ofw_fdt_finddevice(ofw_t ofw, const char *device)
343{
344	int offset;
345
346	offset = fdt_path_offset(fdtp, device);
347	if (offset < 0)
348		return (-1);
349	return (fdt_offset_phandle(offset));
350}
351
352/* Return the fully qualified pathname corresponding to an instance. */
353static ssize_t
354ofw_fdt_instance_to_path(ofw_t ofw, ihandle_t instance, char *buf, size_t len)
355{
356	phandle_t phandle;
357
358	phandle = OF_instance_to_package(instance);
359	if (phandle == -1)
360		return (-1);
361
362	return (OF_package_to_path(phandle, buf, len));
363}
364
365/* Return the fully qualified pathname corresponding to a package. */
366static ssize_t
367ofw_fdt_package_to_path(ofw_t ofw, phandle_t package, char *buf, size_t len)
368{
369
370	return (-1);
371}
372
373static int
374ofw_fdt_fixup(ofw_t ofw)
375{
376#define FDT_MODEL_LEN	80
377	char model[FDT_MODEL_LEN];
378	phandle_t root;
379	ssize_t len;
380	int i;
381
382	if ((root = ofw_fdt_finddevice(ofw, "/")) == -1)
383		return (ENODEV);
384
385	if ((len = ofw_fdt_getproplen(ofw, root, "model")) <= 0)
386		return (0);
387
388	bzero(model, FDT_MODEL_LEN);
389	if (ofw_fdt_getprop(ofw, root, "model", model, FDT_MODEL_LEN) <= 0)
390		return (0);
391
392	/*
393	 * Search fixup table and call handler if appropriate.
394	 */
395	for (i = 0; fdt_fixup_table[i].model != NULL; i++) {
396		if (strncmp(model, fdt_fixup_table[i].model,
397		    FDT_MODEL_LEN) != 0)
398			continue;
399
400		if (fdt_fixup_table[i].handler != NULL)
401			(*fdt_fixup_table[i].handler)(root);
402	}
403
404	return (0);
405}
406
407static int
408ofw_fdt_interpret(ofw_t ofw, const char *cmd, int nret, cell_t *retvals)
409{
410	int rv;
411
412	/*
413	 * Note: FDT does not have the possibility to 'interpret' commands,
414	 * but we abuse the interface a bit to use it for doing non-standard
415	 * operations on the device tree blob.
416	 *
417	 * Currently the only supported 'command' is to trigger performing
418	 * fixups.
419	 */
420	if (strncmp("perform-fixup", cmd, 13) != 0)
421		return (0);
422
423	rv = ofw_fdt_fixup(ofw);
424	if (nret > 0)
425		retvals[0] = rv;
426
427	return (rv);
428}
429