xref: /openbmc/u-boot/env/env.c (revision 3991f42e)
1 /*
2  * Copyright (C) 2017 Google, Inc
3  * Written by Simon Glass <sjg@chromium.org>
4  *
5  * SPDX-License-Identifier:     GPL-2.0+
6  */
7 
8 #include <common.h>
9 #include <environment.h>
10 
11 DECLARE_GLOBAL_DATA_PTR;
12 
13 static struct env_driver *env_driver_lookup(enum env_location loc)
14 {
15 	struct env_driver *drv;
16 	const int n_ents = ll_entry_count(struct env_driver, env_driver);
17 	struct env_driver *entry;
18 
19 	drv = ll_entry_start(struct env_driver, env_driver);
20 	for (entry = drv; entry != drv + n_ents; entry++) {
21 		if (loc == entry->location)
22 			return entry;
23 	}
24 
25 	/* Not found */
26 	return NULL;
27 }
28 
29 static enum env_location env_get_default_location(void)
30 {
31 	if IS_ENABLED(CONFIG_ENV_IS_IN_DATAFLASH)
32 		return ENVL_DATAFLASH;
33 	else if IS_ENABLED(CONFIG_ENV_IS_IN_EEPROM)
34 		return ENVL_EEPROM;
35 	else if IS_ENABLED(CONFIG_ENV_IS_IN_FAT)
36 		return ENVL_FAT;
37 	else if IS_ENABLED(CONFIG_ENV_IS_IN_FLASH)
38 		return ENVL_FLASH;
39 	else if IS_ENABLED(CONFIG_ENV_IS_IN_MMC)
40 		return ENVL_MMC;
41 	else if IS_ENABLED(CONFIG_ENV_IS_IN_NAND)
42 		return ENVL_NAND;
43 	else if IS_ENABLED(CONFIG_ENV_IS_IN_NVRAM)
44 		return ENVL_NVRAM;
45 	else if IS_ENABLED(CONFIG_ENV_IS_IN_REMOTE)
46 		return ENVL_REMOTE;
47 	else if IS_ENABLED(CONFIG_ENV_IS_IN_SPI_FLASH)
48 		return ENVL_SPI_FLASH;
49 	else if IS_ENABLED(CONFIG_ENV_IS_IN_UBI)
50 		return ENVL_UBI;
51 	else if IS_ENABLED(CONFIG_ENV_IS_NOWHERE)
52 		return ENVL_NOWHERE;
53 	else
54 		return ENVL_UNKNOWN;
55 }
56 
57 struct env_driver *env_driver_lookup_default(void)
58 {
59 	enum env_location loc = env_get_default_location();
60 	struct env_driver *drv;
61 
62 	drv = env_driver_lookup(loc);
63 	if (!drv) {
64 		debug("%s: No environment driver for location %d\n", __func__,
65 		      loc);
66 		return NULL;
67 	}
68 
69 	return drv;
70 }
71 
72 int env_get_char(int index)
73 {
74 	struct env_driver *drv = env_driver_lookup_default();
75 	int ret;
76 
77 	if (gd->env_valid == ENV_INVALID)
78 		return default_environment[index];
79 	if (!drv)
80 		return -ENODEV;
81 	if (!drv->get_char)
82 		return *(uchar *)(gd->env_addr + index);
83 	ret = drv->get_char(index);
84 	if (ret < 0) {
85 		debug("%s: Environment failed to load (err=%d)\n",
86 		      __func__, ret);
87 	}
88 
89 	return ret;
90 }
91 
92 int env_load(void)
93 {
94 	struct env_driver *drv = env_driver_lookup_default();
95 	int ret = 0;
96 
97 	if (!drv)
98 		return -ENODEV;
99 	if (!drv->load)
100 		return 0;
101 	ret = drv->load();
102 	if (ret) {
103 		debug("%s: Environment failed to load (err=%d)\n", __func__,
104 		      ret);
105 		return ret;
106 	}
107 
108 	return 0;
109 }
110 
111 int env_save(void)
112 {
113 	struct env_driver *drv = env_driver_lookup_default();
114 	int ret;
115 
116 	if (!drv)
117 		return -ENODEV;
118 	if (!drv->save)
119 		return -ENOSYS;
120 	ret = drv->save();
121 	if (ret) {
122 		debug("%s: Environment failed to save (err=%d)\n", __func__,
123 		      ret);
124 		return ret;
125 	}
126 
127 	return 0;
128 }
129 
130 int env_init(void)
131 {
132 	struct env_driver *drv = env_driver_lookup_default();
133 	int ret = -ENOENT;
134 
135 	if (!drv)
136 		return -ENODEV;
137 	if (drv->init)
138 		ret = drv->init();
139 	if (ret == -ENOENT) {
140 		gd->env_addr = (ulong)&default_environment[0];
141 		gd->env_valid = ENV_VALID;
142 
143 		return 0;
144 	} else if (ret) {
145 		debug("%s: Environment failed to init (err=%d)\n", __func__,
146 		      ret);
147 		return ret;
148 	}
149 
150 	return 0;
151 }
152