1// SPDX-License-Identifier: GPL-2.0+
2/*
3 * Copyright (C) 2015 Masahiro Yamada <yamada.masahiro@socionext.com>
4 *
5 * Based on the original work in Linux by
6 * Copyright (c) 2006  SUSE Linux Products GmbH
7 * Copyright (c) 2006  Tejun Heo <teheo@suse.de>
8 */
9
10#define LOG_CATEGORY LOGC_DEVRES
11
12#include <common.h>
13#include <log.h>
14#include <malloc.h>
15#include <linux/compat.h>
16#include <linux/kernel.h>
17#include <linux/list.h>
18#include <dm/device.h>
19#include <dm/devres.h>
20#include <dm/root.h>
21#include <dm/util.h>
22
23/** enum devres_phase - Shows where resource was allocated
24 *
25 * DEVRES_PHASE_BIND: In the bind() method
26 * DEVRES_PHASE_OFDATA: In the of_to_plat() method
27 * DEVRES_PHASE_PROBE: In the probe() method
28 */
29enum devres_phase {
30	DEVRES_PHASE_BIND,
31	DEVRES_PHASE_OFDATA,
32	DEVRES_PHASE_PROBE,
33};
34
35/**
36 * struct devres - Bookkeeping info for managed device resource
37 * @entry: List to associate this structure with a device
38 * @release: Callback invoked when this resource is released
39 * @probe: Show where this resource was allocated
40 * @name: Name of release function
41 * @size: Size of resource data
42 * @data: Resource data
43 */
44struct devres {
45	struct list_head		entry;
46	dr_release_t			release;
47	enum devres_phase		phase;
48#ifdef CONFIG_DEBUG_DEVRES
49	const char			*name;
50	size_t				size;
51#endif
52	unsigned long long		data[];
53};
54
55#ifdef CONFIG_DEBUG_DEVRES
56static void set_node_dbginfo(struct devres *dr, const char *name, size_t size)
57{
58	dr->name = name;
59	dr->size = size;
60}
61
62static void devres_log(struct udevice *dev, struct devres *dr,
63		       const char *op)
64{
65	log_debug("%s: DEVRES %3s %p %s (%lu bytes)\n", dev->name, op, dr,
66		  dr->name, (unsigned long)dr->size);
67}
68#else /* CONFIG_DEBUG_DEVRES */
69#define set_node_dbginfo(dr, n, s)	do {} while (0)
70#define devres_log(dev, dr, op)		do {} while (0)
71#endif
72
73#if CONFIG_DEBUG_DEVRES
74void *__devres_alloc(dr_release_t release, size_t size, gfp_t gfp,
75		     const char *name)
76#else
77void *_devres_alloc(dr_release_t release, size_t size, gfp_t gfp)
78#endif
79{
80	size_t tot_size = sizeof(struct devres) + size;
81	struct devres *dr;
82
83	dr = kmalloc(tot_size, gfp);
84	if (unlikely(!dr))
85		return NULL;
86
87	INIT_LIST_HEAD(&dr->entry);
88	dr->release = release;
89	set_node_dbginfo(dr, name, size);
90
91	return dr->data;
92}
93
94void devres_free(void *res)
95{
96	if (res) {
97		struct devres *dr = container_of(res, struct devres, data);
98
99		assert_noisy(list_empty(&dr->entry));
100		kfree(dr);
101	}
102}
103
104void devres_add(struct udevice *dev, void *res)
105{
106	struct devres *dr = container_of(res, struct devres, data);
107
108	devres_log(dev, dr, "ADD");
109	assert_noisy(list_empty(&dr->entry));
110	if (dev_get_flags(dev) & DM_FLAG_PLATDATA_VALID)
111		dr->phase = DEVRES_PHASE_PROBE;
112	else if (dev_get_flags(dev) & DM_FLAG_BOUND)
113		dr->phase = DEVRES_PHASE_OFDATA;
114	else
115		dr->phase = DEVRES_PHASE_BIND;
116	list_add_tail(&dr->entry, &dev->devres_head);
117}
118
119void *devres_find(struct udevice *dev, dr_release_t release,
120		  dr_match_t match, void *match_data)
121{
122	struct devres *dr;
123
124	list_for_each_entry_reverse(dr, &dev->devres_head, entry) {
125		if (dr->release != release)
126			continue;
127		if (match && !match(dev, dr->data, match_data))
128			continue;
129		return dr->data;
130	}
131
132	return NULL;
133}
134
135void *devres_get(struct udevice *dev, void *new_res,
136		 dr_match_t match, void *match_data)
137{
138	struct devres *new_dr = container_of(new_res, struct devres, data);
139	void *res;
140
141	res = devres_find(dev, new_dr->release, match, match_data);
142	if (!res) {
143		devres_add(dev, new_res);
144		res = new_res;
145		new_res = NULL;
146	}
147	devres_free(new_res);
148
149	return res;
150}
151
152void *devres_remove(struct udevice *dev, dr_release_t release,
153		    dr_match_t match, void *match_data)
154{
155	void *res;
156
157	res = devres_find(dev, release, match, match_data);
158	if (res) {
159		struct devres *dr = container_of(res, struct devres, data);
160
161		list_del_init(&dr->entry);
162		devres_log(dev, dr, "REM");
163	}
164
165	return res;
166}
167
168int devres_destroy(struct udevice *dev, dr_release_t release,
169		   dr_match_t match, void *match_data)
170{
171	void *res;
172
173	res = devres_remove(dev, release, match, match_data);
174	if (unlikely(!res))
175		return -ENOENT;
176
177	devres_free(res);
178	return 0;
179}
180
181int devres_release(struct udevice *dev, dr_release_t release,
182		   dr_match_t match, void *match_data)
183{
184	void *res;
185
186	res = devres_remove(dev, release, match, match_data);
187	if (unlikely(!res))
188		return -ENOENT;
189
190	(*release)(dev, res);
191	devres_free(res);
192	return 0;
193}
194
195static void release_nodes(struct udevice *dev, struct list_head *head,
196			  bool probe_and_ofdata_only)
197{
198	struct devres *dr, *tmp;
199
200	list_for_each_entry_safe_reverse(dr, tmp, head, entry)  {
201		if (probe_and_ofdata_only && dr->phase == DEVRES_PHASE_BIND)
202			break;
203		devres_log(dev, dr, "REL");
204		dr->release(dev, dr->data);
205		list_del(&dr->entry);
206		kfree(dr);
207	}
208}
209
210void devres_release_probe(struct udevice *dev)
211{
212	release_nodes(dev, &dev->devres_head, true);
213}
214
215void devres_release_all(struct udevice *dev)
216{
217	release_nodes(dev, &dev->devres_head, false);
218}
219
220#ifdef CONFIG_DEBUG_DEVRES
221static char *const devres_phase_name[] = {"BIND", "OFDATA", "PROBE"};
222
223static void dump_resources(struct udevice *dev, int depth)
224{
225	struct devres *dr;
226	struct udevice *child;
227
228	printf("- %s\n", dev->name);
229
230	list_for_each_entry(dr, &dev->devres_head, entry)
231		printf("    %p (%lu byte) %s  %s\n", dr,
232		       (unsigned long)dr->size, dr->name,
233		       devres_phase_name[dr->phase]);
234
235	device_foreach_child(child, dev)
236		dump_resources(child, depth + 1);
237}
238
239void dm_dump_devres(void)
240{
241	struct udevice *root;
242
243	root = dm_root();
244	if (root)
245		dump_resources(root, 0);
246}
247
248void devres_get_stats(const struct udevice *dev, struct devres_stats *stats)
249{
250	struct devres *dr;
251
252	stats->allocs = 0;
253	stats->total_size = 0;
254	list_for_each_entry(dr, &dev->devres_head, entry) {
255		stats->allocs++;
256		stats->total_size += dr->size;
257	}
258}
259
260#endif
261
262/*
263 * Managed kmalloc/kfree
264 */
265static void devm_kmalloc_release(struct udevice *dev, void *res)
266{
267	/* noop */
268}
269
270static int devm_kmalloc_match(struct udevice *dev, void *res, void *data)
271{
272	return res == data;
273}
274
275void *devm_kmalloc(struct udevice *dev, size_t size, gfp_t gfp)
276{
277	void *data;
278
279	data = _devres_alloc(devm_kmalloc_release, size, gfp);
280	if (unlikely(!data))
281		return NULL;
282
283	devres_add(dev, data);
284
285	return data;
286}
287
288void devm_kfree(struct udevice *dev, void *p)
289{
290	int rc;
291
292	rc = devres_destroy(dev, devm_kmalloc_release, devm_kmalloc_match, p);
293	assert_noisy(!rc);
294}
295