summaryrefslogtreecommitdiff
path: root/env/env.c
blob: 003509d34240fcc3355c1c3901405eda49b1f508 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
// SPDX-License-Identifier: GPL-2.0+
/*
 * Copyright (C) 2017 Google, Inc
 * Written by Simon Glass <sjg@chromium.org>
 */

#include <common.h>
#include <environment.h>

DECLARE_GLOBAL_DATA_PTR;

#if defined(CONFIG_NEEDS_MANUAL_RELOC)
void env_fix_drivers(void)
{
	struct env_driver *drv;
	const int n_ents = ll_entry_count(struct env_driver, env_driver);
	struct env_driver *entry;

	drv = ll_entry_start(struct env_driver, env_driver);
	for (entry = drv; entry != drv + n_ents; entry++) {
		if (entry->name)
			entry->name += gd->reloc_off;
		if (entry->load)
			entry->load += gd->reloc_off;
		if (entry->save)
			entry->save += gd->reloc_off;
		if (entry->init)
			entry->init += gd->reloc_off;
	}
}
#endif

static struct env_driver *_env_driver_lookup(enum env_location loc)
{
	struct env_driver *drv;
	const int n_ents = ll_entry_count(struct env_driver, env_driver);
	struct env_driver *entry;

	drv = ll_entry_start(struct env_driver, env_driver);
	for (entry = drv; entry != drv + n_ents; entry++) {
		if (loc == entry->location)
			return entry;
	}

	/* Not found */
	return NULL;
}

static enum env_location env_locations[] = {
#ifdef CONFIG_ENV_IS_IN_EEPROM
	ENVL_EEPROM,
#endif
#ifdef CONFIG_ENV_IS_IN_EXT4
	ENVL_EXT4,
#endif
#ifdef CONFIG_ENV_IS_IN_FAT
	ENVL_FAT,
#endif
#ifdef CONFIG_ENV_IS_IN_FLASH
	ENVL_FLASH,
#endif
#ifdef CONFIG_ENV_IS_IN_MMC
	ENVL_MMC,
#endif
#ifdef CONFIG_ENV_IS_IN_NAND
	ENVL_NAND,
#endif
#ifdef CONFIG_ENV_IS_IN_NVRAM
	ENVL_NVRAM,
#endif
#ifdef CONFIG_ENV_IS_IN_REMOTE
	ENVL_REMOTE,
#endif
#ifdef CONFIG_ENV_IS_IN_SATA
	ENVL_ESATA,
#endif
#ifdef CONFIG_ENV_IS_IN_SPI_FLASH
	ENVL_SPI_FLASH,
#endif
#ifdef CONFIG_ENV_IS_IN_UBI
	ENVL_UBI,
#endif
#ifdef CONFIG_ENV_IS_NOWHERE
	ENVL_NOWHERE,
#endif
};

static bool env_has_inited(enum env_location location)
{
	return gd->env_has_init & BIT(location);
}

static void env_set_inited(enum env_location location)
{
	/*
	 * We're using a 32-bits bitmask stored in gd (env_has_init)
	 * using the above enum value as the bit index. We need to
	 * make sure that we're not overflowing it.
	 */
	BUILD_BUG_ON(ARRAY_SIZE(env_locations) > BITS_PER_LONG);

	gd->env_has_init |= BIT(location);
}

/**
 * env_get_location() - Returns the best env location for a board
 * @op: operations performed on the environment
 * @prio: priority between the multiple environments, 0 being the
 *        highest priority
 *
 * This will return the preferred environment for the given priority.
 * This is overridable by boards if they need to.
 *
 * All implementations are free to use the operation, the priority and
 * any other data relevant to their choice, but must take into account
 * the fact that the lowest prority (0) is the most important location
 * in the system. The following locations should be returned by order
 * of descending priorities, from the highest to the lowest priority.
 *
 * Returns:
 * an enum env_location value on success, a negative error code otherwise
 */
__weak enum env_location env_get_location(enum env_operation op, int prio)
{
	if (prio >= ARRAY_SIZE(env_locations))
		return ENVL_UNKNOWN;

	gd->env_load_prio = prio;

	return env_locations[prio];
}


/**
 * env_driver_lookup() - Finds the most suited environment location
 * @op: operations performed on the environment
 * @prio: priority between the multiple environments, 0 being the
 *        highest priority
 *
 * This will try to find the available environment with the highest
 * priority in the system.
 *
 * Returns:
 * NULL on error, a pointer to a struct env_driver otherwise
 */
static struct env_driver *env_driver_lookup(enum env_operation op, int prio)
{
	enum env_location loc = env_get_location(op, prio);
	struct env_driver *drv;

	if (loc == ENVL_UNKNOWN)
		return NULL;

	drv = _env_driver_lookup(loc);
	if (!drv) {
		debug("%s: No environment driver for location %d\n", __func__,
		      loc);
		return NULL;
	}

	return drv;
}

__weak int env_get_char_spec(int index)
{
	return *(uchar *)(gd->env_addr + index);
}

int env_get_char(int index)
{
	if (gd->env_valid == ENV_INVALID)
		return default_environment[index];
	else
		return env_get_char_spec(index);
}

int env_load(void)
{
	struct env_driver *drv;
	int prio;

	for (prio = 0; (drv = env_driver_lookup(ENVOP_LOAD, prio)); prio++) {
		int ret;

		if (!drv->load)
			continue;

		if (!env_has_inited(drv->location))
			continue;

		printf("Loading Environment from %s... ", drv->name);
		/*
		 * In error case, the error message must be printed during
		 * drv->load() in some underlying API, and it must be exactly
		 * one message.
		 */
		ret = drv->load();
		if (ret) {
			debug("Failed (%d)\n", ret);
		} else {
			printf("OK\n");
			return 0;
		}
	}

	/*
	 * In case of invalid environment, we set the 'default' env location
	 * to the highest priority. In this way, next calls to env_save()
	 * will restore the environment at the right place.
	 */
	env_get_location(ENVOP_LOAD, 0);

	return -ENODEV;
}

int env_save(void)
{
	struct env_driver *drv;

	drv = env_driver_lookup(ENVOP_SAVE, gd->env_load_prio);
	if (drv) {
		int ret;

		if (!drv->save)
			return -ENODEV;

		if (!env_has_inited(drv->location))
			return -ENODEV;

		printf("Saving Environment to %s... ", drv->name);
		ret = drv->save();
		if (ret)
			printf("Failed (%d)\n", ret);
		else
			printf("OK\n");

		if (!ret)
			return 0;
	}

	return -ENODEV;
}

int env_init(void)
{
	struct env_driver *drv;
	int ret = -ENOENT;
	int prio;

	for (prio = 0; (drv = env_driver_lookup(ENVOP_INIT, prio)); prio++) {
		if (!drv->init || !(ret = drv->init()))
			env_set_inited(drv->location);

		debug("%s: Environment %s init done (ret=%d)\n", __func__,
		      drv->name, ret);
	}

	if (!prio)
		return -ENODEV;

	if (ret == -ENOENT) {
		gd->env_addr = (ulong)&default_environment[0];
		gd->env_valid = ENV_VALID;

		return 0;
	}

	return ret;
}