1 // SPDX-License-Identifier: GPL-2.0+
3 * (C) Copyright 2000-2010
4 * Wolfgang Denk, DENX Software Engineering, wd@denx.de.
6 * (C) Copyright 2001 Sysgo Real-Time Solutions, GmbH <www.elinos.com>
7 * Andreas Heppel <aheppel@sysgo.de>
11 #include <bootstage.h>
14 #include <env_internal.h>
17 #include <asm/global_data.h>
18 #include <linux/stddef.h>
22 #include <u-boot/crc.h>
24 DECLARE_GLOBAL_DATA_PTR;
26 /************************************************************************
27 * Default settings to be used when no valid environment is found
29 #include <env_default.h>
31 struct hsearch_data env_htab = {
32 .change_ok = env_flags_validate,
36 * Read an environment variable as a boolean
37 * Return -1 if variable does not exist (default to true)
39 int env_get_yesno(const char *var)
41 char *s = env_get(var);
45 return (*s == '1' || *s == 'y' || *s == 'Y' || *s == 't' || *s == 'T') ?
50 * Look up the variable from the default environment
52 char *env_get_default(const char *name)
55 unsigned long really_valid = gd->env_valid;
56 unsigned long real_gd_flags = gd->flags;
58 /* Pretend that the image is bad. */
59 gd->flags &= ~GD_FLG_ENV_READY;
60 gd->env_valid = ENV_INVALID;
61 ret_val = env_get(name);
62 gd->env_valid = really_valid;
63 gd->flags = real_gd_flags;
67 void env_set_default(const char *s, int flags)
69 if (sizeof(default_environment) > ENV_SIZE) {
70 puts("*** Error - default environment is too large\n\n");
75 if ((flags & H_INTERACTIVE) == 0) {
76 printf("*** Warning - %s, "
77 "using default environment\n\n", s);
82 debug("Using default environment\n");
86 if (himport_r(&env_htab, (char *)default_environment,
87 sizeof(default_environment), '\0', flags, 0,
89 pr_err("## Error: Environment import failed: errno = %d\n",
92 gd->flags |= GD_FLG_ENV_READY;
93 gd->flags |= GD_FLG_ENV_DEFAULT;
97 /* [re]set individual variables to their value in the default environment */
98 int env_set_default_vars(int nvars, char * const vars[], int flags)
101 * Special use-case: import from default environment
102 * (and use \0 as a separator)
104 flags |= H_NOCLEAR | H_DEFAULT;
105 return himport_r(&env_htab, (const char *)default_environment,
106 sizeof(default_environment), '\0',
107 flags, 0, nvars, vars);
111 * Check if CRC is valid and (if yes) import the environment.
112 * Note that "buf" may or may not be aligned.
114 int env_import(const char *buf, int check, int flags)
116 env_t *ep = (env_t *)buf;
121 memcpy(&crc, &ep->crc, sizeof(crc));
123 if (crc32(0, ep->data, ENV_SIZE) != crc) {
124 env_set_default("bad CRC", 0);
125 return -ENOMSG; /* needed for env_load() */
129 if (himport_r(&env_htab, (char *)ep->data, ENV_SIZE, '\0', flags, 0,
131 gd->flags |= GD_FLG_ENV_READY;
135 pr_err("Cannot import environment: errno = %d\n", errno);
137 env_set_default("import failed", 0);
142 #ifdef CONFIG_SYS_REDUNDAND_ENVIRONMENT
143 static unsigned char env_flags;
145 int env_check_redund(const char *buf1, int buf1_read_fail,
146 const char *buf2, int buf2_read_fail)
148 int crc1_ok = 0, crc2_ok = 0;
149 env_t *tmp_env1, *tmp_env2;
151 tmp_env1 = (env_t *)buf1;
152 tmp_env2 = (env_t *)buf2;
154 if (buf1_read_fail && buf2_read_fail) {
155 puts("*** Error - No Valid Environment Area found\n");
157 } else if (buf1_read_fail || buf2_read_fail) {
158 puts("*** Warning - some problems detected ");
159 puts("reading environment; recovered successfully\n");
163 crc1_ok = crc32(0, tmp_env1->data, ENV_SIZE) ==
166 crc2_ok = crc32(0, tmp_env2->data, ENV_SIZE) ==
169 if (!crc1_ok && !crc2_ok) {
170 return -ENOMSG; /* needed for env_load() */
171 } else if (crc1_ok && !crc2_ok) {
172 gd->env_valid = ENV_VALID;
173 } else if (!crc1_ok && crc2_ok) {
174 gd->env_valid = ENV_REDUND;
176 /* both ok - check serial */
177 if (tmp_env1->flags == 255 && tmp_env2->flags == 0)
178 gd->env_valid = ENV_REDUND;
179 else if (tmp_env2->flags == 255 && tmp_env1->flags == 0)
180 gd->env_valid = ENV_VALID;
181 else if (tmp_env1->flags > tmp_env2->flags)
182 gd->env_valid = ENV_VALID;
183 else if (tmp_env2->flags > tmp_env1->flags)
184 gd->env_valid = ENV_REDUND;
185 else /* flags are equal - almost impossible */
186 gd->env_valid = ENV_VALID;
192 int env_import_redund(const char *buf1, int buf1_read_fail,
193 const char *buf2, int buf2_read_fail,
199 ret = env_check_redund(buf1, buf1_read_fail, buf2, buf2_read_fail);
202 env_set_default("bad env area", 0);
204 } else if (ret == -ENOMSG) {
205 env_set_default("bad CRC", 0);
209 if (gd->env_valid == ENV_VALID)
214 env_flags = ep->flags;
216 return env_import((char *)ep, 0, flags);
218 #endif /* CONFIG_SYS_REDUNDAND_ENVIRONMENT */
220 /* Export the environment and generate CRC for it. */
221 int env_export(env_t *env_out)
226 res = (char *)env_out->data;
227 len = hexport_r(&env_htab, '\0', 0, &res, ENV_SIZE, 0, NULL);
229 pr_err("Cannot export environment: errno = %d\n", errno);
233 env_out->crc = crc32(0, env_out->data, ENV_SIZE);
235 #ifdef CONFIG_SYS_REDUNDAND_ENVIRONMENT
236 env_out->flags = ++env_flags; /* increase the serial */
242 void env_relocate(void)
244 #if defined(CONFIG_NEEDS_MANUAL_RELOC)
247 env_htab.change_ok += gd->reloc_off;
249 if (gd->env_valid == ENV_INVALID) {
250 #if defined(CONFIG_ENV_IS_NOWHERE) || defined(CONFIG_SPL_BUILD)
251 /* Environment not changable */
252 env_set_default(NULL, 0);
254 bootstage_error(BOOTSTAGE_ID_NET_CHECKSUM);
255 env_set_default("bad CRC", 0);
262 #ifdef CONFIG_AUTO_COMPLETE
263 int env_complete(char *var, int maxv, char *cmdv[], int bufsz, char *buf,
266 struct env_entry *match;
271 * When doing $ completion, the first character should
272 * obviously be a '$'.
280 * The second one, if present, should be a '{', as some
281 * configuration of the u-boot shell expand ${var} but not
286 else if (var[0] != '\0')
295 while ((idx = hmatch_r(var, idx, &match, &env_htab))) {
296 int vallen = strlen(match->key) + 1;
298 if (found >= maxv - 2 ||
299 bufsz < vallen + (dollar_comp ? 3 : 0))
304 /* Add the '${' prefix to each var when doing $ completion. */
311 memcpy(buf, match->key, vallen);
317 * This one is a bit odd: vallen already contains the
318 * '\0' character but we need to add the '}' suffix,
319 * hence the buf - 1 here. strcpy() will add the '\0'
320 * character just after '}'. buf is then incremented
321 * to account for the extra '}' we just added.
323 strcpy(buf - 1, "}");
328 qsort(cmdv, found, sizeof(cmdv[0]), strcmp_compar);
331 cmdv[found++] = dollar_comp ? "${...}" : "...";