xref: /netbsd-src/sys/dev/fdt/fdtbus.c (revision 627f7eb200a4419d89b531d55fccd2ee3ffdcde0)
1 /* $NetBSD: fdtbus.c,v 1.40 2021/02/05 17:20:32 thorpej 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 1.40 2021/02/05 17:20:32 thorpej Exp $");
31 
32 #include <sys/param.h>
33 #include <sys/systm.h>
34 #include <sys/device.h>
35 #include <sys/kmem.h>
36 #include <sys/cpu.h>
37 
38 #include <sys/bus.h>
39 
40 #include <dev/ofw/openfirm.h>
41 
42 #include <dev/fdt/fdtvar.h>
43 
44 #include <libfdt.h>
45 
46 #include "locators.h"
47 
48 #define	FDT_MAX_PATH	256
49 
50 struct fdt_node {
51 	device_t	n_bus;
52 	device_t	n_dev;
53 	int		n_phandle;
54 	const char	*n_name;
55 	struct fdt_attach_args n_faa;
56 
57 	int		n_cfpass;
58 	cfdata_t	n_cf;
59 
60 	u_int		n_order;
61 
62 	bool		n_pinctrl_init;
63 
64 	TAILQ_ENTRY(fdt_node) n_nodes;
65 };
66 
67 static TAILQ_HEAD(, fdt_node) fdt_nodes =
68     TAILQ_HEAD_INITIALIZER(fdt_nodes);
69 static bool fdt_need_rescan = false;
70 
71 struct fdt_softc {
72 	device_t	sc_dev;
73 	int		sc_phandle;
74 	struct fdt_attach_args sc_faa;
75 };
76 
77 static int	fdt_match(device_t, cfdata_t, void *);
78 static void	fdt_attach(device_t, device_t, void *);
79 static int	fdt_rescan(device_t, const char *, const int *);
80 static void	fdt_childdet(device_t, device_t);
81 
82 static int	fdt_scan_submatch(device_t, cfdata_t, const int *, void *);
83 static void	fdt_scan_best(struct fdt_softc *, struct fdt_node *);
84 static void	fdt_scan(struct fdt_softc *, int);
85 static void	fdt_add_node(struct fdt_node *);
86 static u_int	fdt_get_order(int);
87 static void	fdt_pre_attach(struct fdt_node *);
88 static void	fdt_post_attach(struct fdt_node *);
89 
90 static const struct device_compatible_entry compat_data[] = {
91 	{ .compat = "simple-bus" },
92 	DEVICE_COMPAT_EOL
93 };
94 
95 CFATTACH_DECL2_NEW(simplebus, sizeof(struct fdt_softc),
96     fdt_match, fdt_attach, NULL, NULL, fdt_rescan, fdt_childdet);
97 
98 static int
99 fdt_match(device_t parent, cfdata_t cf, void *aux)
100 {
101 	const struct fdt_attach_args *faa = aux;
102 	const int phandle = faa->faa_phandle;
103 	int match;
104 
105 	/* Check compatible string */
106 	match = of_compatible_match(phandle, compat_data);
107 	if (match)
108 		return match;
109 
110 	/* Some nodes have no compatible string */
111 	if (!of_hasprop(phandle, "compatible")) {
112 		if (OF_finddevice("/clocks") == phandle)
113 			return 1;
114 		if (OF_finddevice("/chosen") == phandle)
115 			return 1;
116 	}
117 
118 	/* Always match the root node */
119 	return OF_finddevice("/") == phandle;
120 }
121 
122 static void
123 fdt_attach(device_t parent, device_t self, void *aux)
124 {
125 	struct fdt_softc *sc = device_private(self);
126 	const struct fdt_attach_args *faa = aux;
127 	const int phandle = faa->faa_phandle;
128 	const char *descr, *model;
129 
130 	sc->sc_dev = self;
131 	sc->sc_phandle = phandle;
132 	sc->sc_faa = *faa;
133 
134 	aprint_naive("\n");
135 
136 	descr = fdtbus_get_string(phandle, "model");
137 	if (descr)
138 		aprint_normal(": %s\n", descr);
139 	else
140 		aprint_normal("\n");
141 
142 	/* Find all child nodes */
143 	fdt_add_bus(self, phandle, &sc->sc_faa);
144 
145 	/* Only the root bus should scan for devices */
146 	if (OF_finddevice("/") != faa->faa_phandle)
147 		return;
148 
149 	/* Set hw.model if available */
150 	model = fdtbus_get_string(phandle, "compatible");
151 	if (model)
152 		cpu_setmodel("%s", model);
153 	else if (descr)
154 		cpu_setmodel("%s", descr);
155 
156 	/* Scan devices */
157 	fdt_rescan(self, NULL, NULL);
158 }
159 
160 static int
161 fdt_rescan(device_t self, const char *ifattr, const int *locs)
162 {
163 	struct fdt_softc *sc = device_private(self);
164 	struct fdt_node *node;
165 	int pass;
166 
167 	TAILQ_FOREACH(node, &fdt_nodes, n_nodes)
168 		fdt_scan_best(sc, node);
169 
170 	pass = 0;
171 	fdt_need_rescan = false;
172 	do {
173 		fdt_scan(sc, pass);
174 		if (fdt_need_rescan == true) {
175 			pass = 0;
176 			TAILQ_FOREACH(node, &fdt_nodes, n_nodes) {
177 				if (node->n_cfpass == -1)
178 					fdt_scan_best(sc, node);
179 			}
180 			fdt_need_rescan = false;
181 		} else {
182 			pass++;
183 		}
184 	} while (pass <= FDTCF_PASS_DEFAULT);
185 
186 	return 0;
187 }
188 
189 static void
190 fdt_childdet(device_t parent, device_t child)
191 {
192 	struct fdt_node *node;
193 
194 	TAILQ_FOREACH(node, &fdt_nodes, n_nodes)
195 		if (node->n_dev == child) {
196 			node->n_dev = NULL;
197 			break;
198 		}
199 }
200 
201 static void
202 fdt_init_attach_args(const struct fdt_attach_args *faa_tmpl, struct fdt_node *node,
203     bool quiet, struct fdt_attach_args *faa)
204 {
205 	*faa = *faa_tmpl;
206 	faa->faa_phandle = node->n_phandle;
207 	faa->faa_name = node->n_name;
208 	faa->faa_quiet = quiet;
209 	faa->faa_dmat = node->n_faa.faa_dmat;
210 }
211 
212 static bool
213 fdt_add_bus_stdmatch(void *arg, int child)
214 {
215 	return fdtbus_status_okay(child);
216 }
217 
218 void
219 fdt_add_bus(device_t bus, const int phandle, struct fdt_attach_args *faa)
220 {
221 	fdt_add_bus_match(bus, phandle, faa, fdt_add_bus_stdmatch, NULL);
222 }
223 
224 void
225 fdt_add_bus_match(device_t bus, const int phandle, struct fdt_attach_args *faa,
226     bool (*fn)(void *, int), void *fnarg)
227 {
228 	int child;
229 
230 	for (child = OF_child(phandle); child; child = OF_peer(child)) {
231 		if (fn && !fn(fnarg, child))
232 			continue;
233 
234 		fdt_add_child(bus, child, faa, fdt_get_order(child));
235 	}
236 }
237 
238 static int
239 fdt_dma_translate(int phandle, struct fdt_dma_range **ranges, u_int *nranges)
240 {
241 	const uint8_t *data;
242 	int len, n;
243 
244 	const int parent = OF_parent(phandle);
245 	if (parent == -1)
246 		return 1;	/* done searching */
247 
248 	data = fdtbus_get_prop(phandle, "dma-ranges", &len);
249 	if (data == NULL)
250 		return 1;	/* no dma-ranges property, stop searching */
251 
252 	if (len == 0)
253 		return 0;	/* dma-ranges property is empty, keep going */
254 
255 	const int addr_cells = fdtbus_get_addr_cells(phandle);
256 	const int size_cells = fdtbus_get_size_cells(phandle);
257 	const int paddr_cells = fdtbus_get_addr_cells(parent);
258 	if (addr_cells == -1 || size_cells == -1 || paddr_cells == -1)
259 		return 1;
260 
261 	const int entry_size = (addr_cells + paddr_cells + size_cells) * 4;
262 
263 	*nranges = len / entry_size;
264 	*ranges = kmem_alloc(sizeof(struct fdt_dma_range) * *nranges, KM_SLEEP);
265 	for (n = 0; len >= entry_size; n++, len -= entry_size) {
266 		const uint64_t cba = fdtbus_get_cells(data, addr_cells);
267 		data += addr_cells * 4;
268 		const uint64_t pba = fdtbus_get_cells(data, paddr_cells);
269 		data += paddr_cells * 4;
270 		const uint64_t cl = fdtbus_get_cells(data, size_cells);
271 		data += size_cells * 4;
272 
273 		(*ranges)[n].dr_sysbase = pba;
274 		(*ranges)[n].dr_busbase = cba;
275 		(*ranges)[n].dr_len = cl;
276 	}
277 
278 	return 1;
279 }
280 
281 static bus_dma_tag_t
282 fdt_get_dma_tag(struct fdt_node *node)
283 {
284 	struct fdt_dma_range *ranges = NULL;
285 	u_int nranges = 0;
286 	int parent;
287 
288 	parent = OF_parent(node->n_phandle);
289 	while (parent != -1) {
290 		if (fdt_dma_translate(parent, &ranges, &nranges) != 0)
291 			break;
292 		parent = OF_parent(parent);
293 	}
294 
295 	return fdtbus_dma_tag_create(node->n_phandle, ranges, nranges);
296 }
297 
298 void
299 fdt_add_child(device_t bus, const int child, struct fdt_attach_args *faa,
300     u_int order)
301 {
302 	struct fdt_node *node;
303 
304 	/* Add the node to our device list */
305 	node = kmem_zalloc(sizeof(*node), KM_SLEEP);
306 	node->n_bus = bus;
307 	node->n_dev = NULL;
308 	node->n_phandle = child;
309 	node->n_name = fdtbus_get_string(child, "name");
310 	node->n_cfpass = -1;
311 	node->n_cf = NULL;
312 	node->n_order = order;
313 	node->n_faa = *faa;
314 	node->n_faa.faa_phandle = child;
315 	node->n_faa.faa_name = node->n_name;
316 	node->n_faa.faa_dmat = fdt_get_dma_tag(node);
317 
318 	fdt_add_node(node);
319 	fdt_need_rescan = true;
320 }
321 
322 static int
323 fdt_scan_submatch(device_t parent, cfdata_t cf, const int *locs, void *aux)
324 {
325 	if (locs[FDTCF_PASS] != FDTCF_PASS_DEFAULT &&
326 	    locs[FDTCF_PASS] != cf->cf_loc[FDTCF_PASS])
327 		return 0;
328 
329 	return config_stdsubmatch(parent, cf, locs, aux);
330 }
331 
332 static void
333 fdt_scan_best(struct fdt_softc *sc, struct fdt_node *node)
334 {
335 	struct fdt_attach_args faa;
336 	cfdata_t cf, best_cf;
337 	int match, best_match, best_pass;
338 
339 	best_cf = NULL;
340 	best_match = 0;
341 	best_pass = FDTCF_PASS_DEFAULT;
342 
343 	for (int pass = 0; pass <= FDTCF_PASS_DEFAULT; pass++) {
344 		const int locs[FDTCF_NLOCS] = {
345 			[FDTCF_PASS] = pass
346 		};
347 		fdt_init_attach_args(&sc->sc_faa, node, true, &faa);
348 		cf = config_search_loc(fdt_scan_submatch, node->n_bus, "fdt", locs, &faa);
349 		if (cf == NULL)
350 			continue;
351 		match = config_match(node->n_bus, cf, &faa);
352 		if (match > best_match) {
353 			best_match = match;
354 			best_cf = cf;
355 			best_pass = pass;
356 		}
357 	}
358 
359 	node->n_cf = best_cf;
360 	node->n_cfpass = best_pass;
361 }
362 
363 static void
364 fdt_scan(struct fdt_softc *sc, int pass)
365 {
366 	struct fdt_node *node;
367 	struct fdt_attach_args faa;
368 	const int locs[FDTCF_NLOCS] = {
369 		[FDTCF_PASS] = pass
370 	};
371 	bool quiet = pass != FDTCF_PASS_DEFAULT;
372 
373 	TAILQ_FOREACH(node, &fdt_nodes, n_nodes) {
374 		if (node->n_cfpass != pass || node->n_dev != NULL)
375 			continue;
376 
377 		fdt_init_attach_args(&sc->sc_faa, node, quiet, &faa);
378 
379 		if (quiet && node->n_cf == NULL) {
380 			/*
381 			 * No match for this device, skip it.
382 			 */
383 			continue;
384 		}
385 
386 		/*
387 		 * Attach the device.
388 		 */
389 		fdt_pre_attach(node);
390 
391 		if (quiet) {
392 			node->n_dev = config_attach_loc(node->n_bus, node->n_cf, locs,
393 			    &faa, fdtbus_print);
394 		} else {
395 			/*
396 			 * Default pass.
397 			 */
398 			node->n_dev = config_found_sm_loc(node->n_bus, "fdt", locs,
399 			    &faa, fdtbus_print, fdt_scan_submatch);
400 		}
401 
402 		if (node->n_dev != NULL)
403 			fdt_post_attach(node);
404 	}
405 }
406 
407 static void
408 fdt_pre_attach(struct fdt_node *node)
409 {
410 	const char *cfgname;
411 	int error;
412 
413 	node->n_pinctrl_init = fdtbus_pinctrl_has_config(node->n_phandle, "init");
414 
415 	cfgname = node->n_pinctrl_init ? "init" : "default";
416 
417 	aprint_debug_dev(node->n_bus, "set %s config for %s\n", cfgname, node->n_name);
418 
419 	error = fdtbus_pinctrl_set_config(node->n_phandle, cfgname);
420 	if (error != 0 && error != ENOENT)
421 		aprint_debug_dev(node->n_bus,
422 		    "failed to set %s config on %s: %d\n",
423 		    cfgname, node->n_name, error);
424 }
425 
426 static void
427 fdt_post_attach(struct fdt_node *node)
428 {
429 	char buf[FDT_MAX_PATH];
430 	prop_dictionary_t dict;
431 	int error;
432 
433 	dict = device_properties(node->n_dev);
434 	if (fdtbus_get_path(node->n_phandle, buf, sizeof(buf)))
435 		prop_dictionary_set_string(dict, "fdt-path", buf);
436 
437 	if (node->n_pinctrl_init) {
438 		aprint_debug_dev(node->n_bus, "set default config for %s\n", node->n_name);
439 		error = fdtbus_pinctrl_set_config(node->n_phandle, "default");
440 		if (error != 0 && error != ENOENT)
441 			aprint_debug_dev(node->n_bus,
442 			    "failed to set default config on %s: %d\n",
443 			    node->n_name, error);
444 	}
445 }
446 
447 static void
448 fdt_add_node(struct fdt_node *new_node)
449 {
450 	struct fdt_node *node;
451 
452 	TAILQ_FOREACH(node, &fdt_nodes, n_nodes)
453 		if (node->n_order > new_node->n_order) {
454 			TAILQ_INSERT_BEFORE(node, new_node, n_nodes);
455 			return;
456 		}
457 	TAILQ_INSERT_TAIL(&fdt_nodes, new_node, n_nodes);
458 }
459 
460 void
461 fdt_remove_byhandle(int phandle)
462 {
463 	struct fdt_node *node;
464 
465 	TAILQ_FOREACH(node, &fdt_nodes, n_nodes) {
466 		if (node->n_phandle == phandle) {
467 			TAILQ_REMOVE(&fdt_nodes, node, n_nodes);
468 			return;
469 		}
470 	}
471 }
472 
473 void
474 fdt_remove_bycompat(const char *compatible[])
475 {
476 	struct fdt_node *node, *next;
477 
478 	TAILQ_FOREACH_SAFE(node, &fdt_nodes, n_nodes, next) {
479 		if (of_compatible(node->n_phandle, compatible)) {
480 			TAILQ_REMOVE(&fdt_nodes, node, n_nodes);
481 		}
482 	}
483 }
484 
485 int
486 fdt_find_with_property(const char *prop, int *pindex)
487 {
488 	struct fdt_node *node;
489 	int index = 0;
490 
491 	TAILQ_FOREACH(node, &fdt_nodes, n_nodes) {
492 		if (index++ < *pindex)
493 			continue;
494 		if (of_hasprop(node->n_phandle, prop)) {
495 			*pindex = index;
496 			return node->n_phandle;
497 		}
498 	}
499 
500 	return -1;
501 }
502 
503 static u_int
504 fdt_get_order(int phandle)
505 {
506 	u_int val = UINT_MAX;
507 	int child;
508 
509 	of_getprop_uint32(phandle, "phandle", &val);
510 
511 	for (child = OF_child(phandle); child; child = OF_peer(child)) {
512 		u_int child_val = fdt_get_order(child);
513 		if (child_val < val)
514 			val = child_val;
515 	}
516 
517 	return val;
518 }
519 
520 int
521 fdtbus_print(void *aux, const char *pnp)
522 {
523 	const struct fdt_attach_args * const faa = aux;
524 	char buf[FDT_MAX_PATH];
525 	const char *name = buf;
526 	int len;
527 
528 	if (pnp && faa->faa_quiet)
529 		return QUIET;
530 
531 	/* Skip "not configured" for nodes w/o compatible property */
532 	if (pnp && OF_getproplen(faa->faa_phandle, "compatible") <= 0)
533 		return QUIET;
534 
535 	if (!fdtbus_get_path(faa->faa_phandle, buf, sizeof(buf)))
536 		name = faa->faa_name;
537 
538 	if (pnp) {
539 		aprint_normal("%s at %s", name, pnp);
540 		const char *compat = fdt_getprop(fdtbus_get_data(),
541 		    fdtbus_phandle2offset(faa->faa_phandle), "compatible",
542 		    &len);
543 		while (len > 0) {
544 			aprint_debug(" <%s>", compat);
545 			len -= (strlen(compat) + 1);
546 			compat += (strlen(compat) + 1);
547 		}
548 	} else
549 		aprint_debug(" (%s)", name);
550 
551 	return UNCONF;
552 }
553 
554 void
555 fdtbus_device_register(device_t dev, void *aux)
556 {
557 	/* All we do here is set the devhandle in the device_t. */
558 	int phandle = -1;
559 
560 	if (device_attached_to_iattr(dev, "fdt")) {
561 		const struct fdt_attach_args *faa = aux;
562 		phandle = faa->faa_phandle;
563 	} else {
564 		return;
565 	}
566 	KASSERT(phandle != -1);
567 
568 	of_device_register(dev, phandle);
569 }
570