xref: /netbsd-src/sys/dev/fdt/fdtbus.c (revision 7330f729ccf0bd976a06f95fad452fe774fc7fd1)
1 /* $NetBSD: fdtbus.c,v 1.30 2019/10/01 23:32:52 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: fdtbus.c,v 1.30 2019/10/01 23:32:52 jmcneill Exp $");
31 
32 #include <sys/param.h>
33 #include <sys/systm.h>
34 #include <sys/device.h>
35 #include <sys/kmem.h>
36 
37 #include <sys/bus.h>
38 
39 #include <dev/ofw/openfirm.h>
40 
41 #include <dev/fdt/fdtvar.h>
42 
43 #include <libfdt.h>
44 
45 #include "locators.h"
46 
47 #define	FDT_MAX_PATH	256
48 
49 struct fdt_node {
50 	device_t	n_bus;
51 	device_t	n_dev;
52 	int		n_phandle;
53 	const char	*n_name;
54 	struct fdt_attach_args n_faa;
55 	cfdata_t	n_cf;
56 
57 	u_int		n_order;
58 
59 	bool		n_pinctrl_init;
60 
61 	TAILQ_ENTRY(fdt_node) n_nodes;
62 };
63 
64 static TAILQ_HEAD(, fdt_node) fdt_nodes =
65     TAILQ_HEAD_INITIALIZER(fdt_nodes);
66 static bool fdt_need_rescan = false;
67 
68 struct fdt_softc {
69 	device_t	sc_dev;
70 	int		sc_phandle;
71 	struct fdt_attach_args sc_faa;
72 };
73 
74 static int	fdt_match(device_t, cfdata_t, void *);
75 static void	fdt_attach(device_t, device_t, void *);
76 static int	fdt_rescan(device_t, const char *, const int *);
77 static void	fdt_childdet(device_t, device_t);
78 
79 static int	fdt_scan_submatch(device_t, cfdata_t, const int *, void *);
80 static cfdata_t	fdt_scan_best(struct fdt_softc *, struct fdt_node *);
81 static void	fdt_scan(struct fdt_softc *, int);
82 static void	fdt_add_node(struct fdt_node *);
83 static u_int	fdt_get_order(int);
84 static void	fdt_pre_attach(struct fdt_node *);
85 static void	fdt_post_attach(struct fdt_node *);
86 
87 static const char * const fdtbus_compatible[] =
88     { "simple-bus", NULL };
89 
90 CFATTACH_DECL2_NEW(simplebus, sizeof(struct fdt_softc),
91     fdt_match, fdt_attach, NULL, NULL, fdt_rescan, fdt_childdet);
92 
93 static int
94 fdt_match(device_t parent, cfdata_t cf, void *aux)
95 {
96 	const struct fdt_attach_args *faa = aux;
97 	const int phandle = faa->faa_phandle;
98 	int match;
99 
100 	/* Check compatible string */
101 	match = of_match_compatible(phandle, fdtbus_compatible);
102 	if (match)
103 		return match;
104 
105 	/* Some nodes have no compatible string */
106 	if (!of_hasprop(phandle, "compatible")) {
107 		if (OF_finddevice("/clocks") == phandle)
108 			return 1;
109 		if (OF_finddevice("/chosen") == phandle)
110 			return 1;
111 	}
112 
113 	/* Always match the root node */
114 	return OF_finddevice("/") == phandle;
115 }
116 
117 static void
118 fdt_attach(device_t parent, device_t self, void *aux)
119 {
120 	struct fdt_softc *sc = device_private(self);
121 	const struct fdt_attach_args *faa = aux;
122 	const int phandle = faa->faa_phandle;
123 	const char *descr;
124 
125 	sc->sc_dev = self;
126 	sc->sc_phandle = phandle;
127 	sc->sc_faa = *faa;
128 
129 	aprint_naive("\n");
130 
131 	descr = fdtbus_get_string(phandle, "model");
132 	if (descr)
133 		aprint_normal(": %s\n", descr);
134 	else
135 		aprint_normal("\n");
136 
137 	/* Find all child nodes */
138 	fdt_add_bus(self, phandle, &sc->sc_faa);
139 
140 	/* Only the root bus should scan for devices */
141 	if (OF_finddevice("/") != faa->faa_phandle)
142 		return;
143 
144 	/* Scan devices */
145 	fdt_rescan(self, NULL, NULL);
146 }
147 
148 static int
149 fdt_rescan(device_t self, const char *ifattr, const int *locs)
150 {
151 	struct fdt_softc *sc = device_private(self);
152 	struct fdt_node *node;
153 	int pass;
154 
155 	TAILQ_FOREACH(node, &fdt_nodes, n_nodes)
156 		node->n_cf = fdt_scan_best(sc, node);
157 
158 	pass = 0;
159 	fdt_need_rescan = false;
160 	do {
161 		fdt_scan(sc, pass);
162 		if (fdt_need_rescan == true) {
163 			pass = 0;
164 			TAILQ_FOREACH(node, &fdt_nodes, n_nodes) {
165 				if (node->n_dev == NULL)
166 					node->n_cf = fdt_scan_best(sc, node);
167 			}
168 			fdt_need_rescan = false;
169 		} else {
170 			pass++;
171 		}
172 	} while (pass <= FDTCF_PASS_DEFAULT);
173 
174 	return 0;
175 }
176 
177 static void
178 fdt_childdet(device_t parent, device_t child)
179 {
180 	struct fdt_node *node;
181 
182 	TAILQ_FOREACH(node, &fdt_nodes, n_nodes)
183 		if (node->n_dev == child) {
184 			node->n_dev = NULL;
185 			break;
186 		}
187 }
188 
189 static void
190 fdt_init_attach_args(const struct fdt_attach_args *faa_tmpl, struct fdt_node *node,
191     bool quiet, struct fdt_attach_args *faa)
192 {
193 	*faa = *faa_tmpl;
194 	faa->faa_phandle = node->n_phandle;
195 	faa->faa_name = node->n_name;
196 	faa->faa_quiet = quiet;
197 }
198 
199 static bool
200 fdt_add_bus_stdmatch(void *arg, int child)
201 {
202 	return fdtbus_status_okay(child);
203 }
204 
205 void
206 fdt_add_bus(device_t bus, const int phandle, struct fdt_attach_args *faa)
207 {
208 	fdt_add_bus_match(bus, phandle, faa, fdt_add_bus_stdmatch, NULL);
209 }
210 
211 void
212 fdt_add_bus_match(device_t bus, const int phandle, struct fdt_attach_args *faa,
213     bool (*fn)(void *, int), void *fnarg)
214 {
215 	int child;
216 
217 	for (child = OF_child(phandle); child; child = OF_peer(child)) {
218 		if (fn && !fn(fnarg, child))
219 			continue;
220 
221 		fdt_add_child(bus, child, faa, fdt_get_order(child));
222 	}
223 }
224 
225 void
226 fdt_add_child(device_t bus, const int child, struct fdt_attach_args *faa,
227     u_int order)
228 {
229 	struct fdt_node *node;
230 
231 	/* Add the node to our device list */
232 	node = kmem_alloc(sizeof(*node), KM_SLEEP);
233 	node->n_bus = bus;
234 	node->n_dev = NULL;
235 	node->n_phandle = child;
236 	node->n_name = fdtbus_get_string(child, "name");
237 	node->n_order = order;
238 	node->n_faa = *faa;
239 	node->n_faa.faa_phandle = child;
240 	node->n_faa.faa_name = node->n_name;
241 
242 	fdt_add_node(node);
243 	fdt_need_rescan = true;
244 }
245 
246 static int
247 fdt_scan_submatch(device_t parent, cfdata_t cf, const int *locs, void *aux)
248 {
249 	if (locs[FDTCF_PASS] != FDTCF_PASS_DEFAULT &&
250 	    locs[FDTCF_PASS] != cf->cf_loc[FDTCF_PASS])
251 		return 0;
252 
253 	return config_stdsubmatch(parent, cf, locs, aux);
254 }
255 
256 static cfdata_t
257 fdt_scan_best(struct fdt_softc *sc, struct fdt_node *node)
258 {
259 	struct fdt_attach_args faa;
260 	cfdata_t cf, best_cf;
261 	int match, best_match;
262 
263 	best_cf = NULL;
264 	best_match = 0;
265 
266 	for (int pass = 0; pass <= FDTCF_PASS_DEFAULT; pass++) {
267 		const int locs[FDTCF_NLOCS] = {
268 			[FDTCF_PASS] = pass
269 		};
270 		fdt_init_attach_args(&sc->sc_faa, node, true, &faa);
271 		cf = config_search_loc(fdt_scan_submatch, node->n_bus, "fdt", locs, &faa);
272 		if (cf == NULL)
273 			continue;
274 		match = config_match(node->n_bus, cf, &faa);
275 		if (match > best_match) {
276 			best_match = match;
277 			best_cf = cf;
278 		}
279 	}
280 
281 	return best_cf;
282 }
283 
284 static void
285 fdt_scan(struct fdt_softc *sc, int pass)
286 {
287 	struct fdt_node *node;
288 	struct fdt_attach_args faa;
289 	const int locs[FDTCF_NLOCS] = {
290 		[FDTCF_PASS] = pass
291 	};
292 	bool quiet = pass != FDTCF_PASS_DEFAULT;
293 	prop_dictionary_t dict;
294 	char buf[FDT_MAX_PATH];
295 
296 	TAILQ_FOREACH(node, &fdt_nodes, n_nodes) {
297 		if (node->n_dev != NULL)
298 			continue;
299 
300 		fdt_init_attach_args(&sc->sc_faa, node, quiet, &faa);
301 
302 		if (quiet) {
303 			/*
304 			 * No match for this device, skip it.
305 			 */
306 			if (node->n_cf == NULL)
307 				continue;
308 
309 			/*
310 			 * Make sure we don't attach before a better match in a later pass.
311 			 */
312 			cfdata_t cf_pass =
313 			    config_search_loc(fdt_scan_submatch, node->n_bus, "fdt", locs, &faa);
314 			if (node->n_cf != cf_pass)
315 				continue;
316 
317 			/*
318 			 * Attach the device.
319 			 */
320 			fdt_pre_attach(node);
321 			node->n_dev = config_attach_loc(node->n_bus, cf_pass, locs,
322 			    &faa, fdtbus_print);
323 			if (node->n_dev != NULL)
324 				fdt_post_attach(node);
325 		} else {
326 			/*
327 			 * Default pass.
328 			 */
329 			fdt_pre_attach(node);
330 			node->n_dev = config_found_sm_loc(node->n_bus, "fdt", locs,
331 			    &faa, fdtbus_print, fdt_scan_submatch);
332 			if (node->n_dev != NULL)
333 				fdt_post_attach(node);
334 		}
335 
336 		if (node->n_dev) {
337 			dict = device_properties(node->n_dev);
338 			if (fdtbus_get_path(node->n_phandle, buf, sizeof(buf)))
339 				prop_dictionary_set_cstring(dict, "fdt-path", buf);
340 		}
341 	}
342 }
343 
344 static void
345 fdt_pre_attach(struct fdt_node *node)
346 {
347 	const char *cfgname;
348 	int error;
349 
350 	node->n_pinctrl_init = fdtbus_pinctrl_has_config(node->n_phandle, "init");
351 
352 	cfgname = node->n_pinctrl_init ? "init" : "default";
353 
354 	aprint_debug_dev(node->n_bus, "set %s config for %s\n", cfgname, node->n_name);
355 
356 	error = fdtbus_pinctrl_set_config(node->n_phandle, cfgname);
357 	if (error != 0 && error != ENOENT)
358 		aprint_debug_dev(node->n_bus,
359 		    "failed to set %s config on %s: %d\n",
360 		    cfgname, node->n_name, error);
361 }
362 
363 static void
364 fdt_post_attach(struct fdt_node *node)
365 {
366 	int error;
367 
368 	if (node->n_pinctrl_init) {
369 		aprint_debug_dev(node->n_bus, "set default config for %s\n", node->n_name);
370 		error = fdtbus_pinctrl_set_config(node->n_phandle, "default");
371 		if (error != 0 && error != ENOENT)
372 			aprint_debug_dev(node->n_bus,
373 			    "failed to set default config on %s: %d\n",
374 			    node->n_name, error);
375 	}
376 }
377 
378 static void
379 fdt_add_node(struct fdt_node *new_node)
380 {
381 	struct fdt_node *node;
382 
383 	TAILQ_FOREACH(node, &fdt_nodes, n_nodes)
384 		if (node->n_order > new_node->n_order) {
385 			TAILQ_INSERT_BEFORE(node, new_node, n_nodes);
386 			return;
387 		}
388 	TAILQ_INSERT_TAIL(&fdt_nodes, new_node, n_nodes);
389 }
390 
391 void
392 fdt_remove_byhandle(int phandle)
393 {
394 	struct fdt_node *node;
395 
396 	TAILQ_FOREACH(node, &fdt_nodes, n_nodes) {
397 		if (node->n_phandle == phandle) {
398 			TAILQ_REMOVE(&fdt_nodes, node, n_nodes);
399 			return;
400 		}
401 	}
402 }
403 
404 void
405 fdt_remove_bycompat(const char *compatible[])
406 {
407 	struct fdt_node *node, *next;
408 
409 	TAILQ_FOREACH_SAFE(node, &fdt_nodes, n_nodes, next) {
410 		if (of_match_compatible(node->n_phandle, compatible)) {
411 			TAILQ_REMOVE(&fdt_nodes, node, n_nodes);
412 		}
413 	}
414 }
415 
416 int
417 fdt_find_with_property(const char *prop, int *pindex)
418 {
419 	struct fdt_node *node;
420 	int index = 0;
421 
422 	TAILQ_FOREACH(node, &fdt_nodes, n_nodes) {
423 		if (index++ < *pindex)
424 			continue;
425 		if (of_hasprop(node->n_phandle, prop)) {
426 			*pindex = index;
427 			return node->n_phandle;
428 		}
429 	}
430 
431 	return -1;
432 }
433 
434 static u_int
435 fdt_get_order(int phandle)
436 {
437 	u_int val = UINT_MAX;
438 	int child;
439 
440 	of_getprop_uint32(phandle, "phandle", &val);
441 
442 	for (child = OF_child(phandle); child; child = OF_peer(child)) {
443 		u_int child_val = fdt_get_order(child);
444 		if (child_val < val)
445 			val = child_val;
446 	}
447 
448 	return val;
449 }
450 
451 int
452 fdtbus_print(void *aux, const char *pnp)
453 {
454 	const struct fdt_attach_args * const faa = aux;
455 	char buf[FDT_MAX_PATH];
456 	const char *name = buf;
457 	int len;
458 
459 	if (pnp && faa->faa_quiet)
460 		return QUIET;
461 
462 	/* Skip "not configured" for nodes w/o compatible property */
463 	if (pnp && OF_getproplen(faa->faa_phandle, "compatible") <= 0)
464 		return QUIET;
465 
466 	if (!fdtbus_get_path(faa->faa_phandle, buf, sizeof(buf)))
467 		name = faa->faa_name;
468 
469 	if (pnp) {
470 		aprint_normal("%s at %s", name, pnp);
471 		const char *compat = fdt_getprop(fdtbus_get_data(),
472 		    fdtbus_phandle2offset(faa->faa_phandle), "compatible",
473 		    &len);
474 		while (len > 0) {
475 			aprint_debug(" <%s>", compat);
476 			len -= (strlen(compat) + 1);
477 			compat += (strlen(compat) + 1);
478 		}
479 	} else
480 		aprint_debug(" (%s)", name);
481 
482 	return UNCONF;
483 }
484