1*83d290c5STom Rini // SPDX-License-Identifier: GPL-2.0+
20649cd0dSSimon Glass /*
30649cd0dSSimon Glass * (C) Copyright 2012
40649cd0dSSimon Glass * Joe Hershberger, National Instruments, joe.hershberger@ni.com
50649cd0dSSimon Glass */
60649cd0dSSimon Glass
70649cd0dSSimon Glass #include <common.h>
80649cd0dSSimon Glass #include <environment.h>
90649cd0dSSimon Glass
100649cd0dSSimon Glass #if defined(CONFIG_NEEDS_MANUAL_RELOC)
110649cd0dSSimon Glass DECLARE_GLOBAL_DATA_PTR;
120649cd0dSSimon Glass #endif
130649cd0dSSimon Glass
140649cd0dSSimon Glass /*
150649cd0dSSimon Glass * Look up a callback function pointer by name
160649cd0dSSimon Glass */
find_env_callback(const char * name)170649cd0dSSimon Glass static struct env_clbk_tbl *find_env_callback(const char *name)
180649cd0dSSimon Glass {
190649cd0dSSimon Glass struct env_clbk_tbl *clbkp;
200649cd0dSSimon Glass int i;
210649cd0dSSimon Glass int num_callbacks = ll_entry_count(struct env_clbk_tbl, env_clbk);
220649cd0dSSimon Glass
230649cd0dSSimon Glass if (name == NULL)
240649cd0dSSimon Glass return NULL;
250649cd0dSSimon Glass
260649cd0dSSimon Glass /* look up the callback in the linker-list */
270649cd0dSSimon Glass for (i = 0, clbkp = ll_entry_start(struct env_clbk_tbl, env_clbk);
280649cd0dSSimon Glass i < num_callbacks;
290649cd0dSSimon Glass i++, clbkp++) {
300649cd0dSSimon Glass if (strcmp(name, clbkp->name) == 0)
310649cd0dSSimon Glass return clbkp;
320649cd0dSSimon Glass }
330649cd0dSSimon Glass
340649cd0dSSimon Glass return NULL;
350649cd0dSSimon Glass }
360649cd0dSSimon Glass
370649cd0dSSimon Glass static int first_call = 1;
380649cd0dSSimon Glass static const char *callback_list;
390649cd0dSSimon Glass
400649cd0dSSimon Glass /*
410649cd0dSSimon Glass * Look for a possible callback for a newly added variable
420649cd0dSSimon Glass * This is called specifically when the variable did not exist in the hash
430649cd0dSSimon Glass * previously, so the blanket update did not find this variable.
440649cd0dSSimon Glass */
env_callback_init(ENTRY * var_entry)450649cd0dSSimon Glass void env_callback_init(ENTRY *var_entry)
460649cd0dSSimon Glass {
470649cd0dSSimon Glass const char *var_name = var_entry->key;
480649cd0dSSimon Glass char callback_name[256] = "";
490649cd0dSSimon Glass struct env_clbk_tbl *clbkp;
500649cd0dSSimon Glass int ret = 1;
510649cd0dSSimon Glass
520649cd0dSSimon Glass if (first_call) {
5300caae6dSSimon Glass callback_list = env_get(ENV_CALLBACK_VAR);
540649cd0dSSimon Glass first_call = 0;
550649cd0dSSimon Glass }
560649cd0dSSimon Glass
570649cd0dSSimon Glass /* look in the ".callbacks" var for a reference to this variable */
580649cd0dSSimon Glass if (callback_list != NULL)
590649cd0dSSimon Glass ret = env_attr_lookup(callback_list, var_name, callback_name);
600649cd0dSSimon Glass
610649cd0dSSimon Glass /* only if not found there, look in the static list */
620649cd0dSSimon Glass if (ret)
630649cd0dSSimon Glass ret = env_attr_lookup(ENV_CALLBACK_LIST_STATIC, var_name,
640649cd0dSSimon Glass callback_name);
650649cd0dSSimon Glass
660649cd0dSSimon Glass /* if an association was found, set the callback pointer */
670649cd0dSSimon Glass if (!ret && strlen(callback_name)) {
680649cd0dSSimon Glass clbkp = find_env_callback(callback_name);
690649cd0dSSimon Glass if (clbkp != NULL)
700649cd0dSSimon Glass #if defined(CONFIG_NEEDS_MANUAL_RELOC)
710649cd0dSSimon Glass var_entry->callback = clbkp->callback + gd->reloc_off;
720649cd0dSSimon Glass #else
730649cd0dSSimon Glass var_entry->callback = clbkp->callback;
740649cd0dSSimon Glass #endif
750649cd0dSSimon Glass }
760649cd0dSSimon Glass }
770649cd0dSSimon Glass
780649cd0dSSimon Glass /*
790649cd0dSSimon Glass * Called on each existing env var prior to the blanket update since removing
800649cd0dSSimon Glass * a callback association should remove its callback.
810649cd0dSSimon Glass */
clear_callback(ENTRY * entry)820649cd0dSSimon Glass static int clear_callback(ENTRY *entry)
830649cd0dSSimon Glass {
840649cd0dSSimon Glass entry->callback = NULL;
850649cd0dSSimon Glass
860649cd0dSSimon Glass return 0;
870649cd0dSSimon Glass }
880649cd0dSSimon Glass
890649cd0dSSimon Glass /*
900649cd0dSSimon Glass * Call for each element in the list that associates variables to callbacks
910649cd0dSSimon Glass */
set_callback(const char * name,const char * value,void * priv)920649cd0dSSimon Glass static int set_callback(const char *name, const char *value, void *priv)
930649cd0dSSimon Glass {
940649cd0dSSimon Glass ENTRY e, *ep;
950649cd0dSSimon Glass struct env_clbk_tbl *clbkp;
960649cd0dSSimon Glass
970649cd0dSSimon Glass e.key = name;
980649cd0dSSimon Glass e.data = NULL;
990649cd0dSSimon Glass e.callback = NULL;
1000649cd0dSSimon Glass hsearch_r(e, FIND, &ep, &env_htab, 0);
1010649cd0dSSimon Glass
1020649cd0dSSimon Glass /* does the env variable actually exist? */
1030649cd0dSSimon Glass if (ep != NULL) {
1040649cd0dSSimon Glass /* the assocaition delares no callback, so remove the pointer */
1050649cd0dSSimon Glass if (value == NULL || strlen(value) == 0)
1060649cd0dSSimon Glass ep->callback = NULL;
1070649cd0dSSimon Glass else {
1080649cd0dSSimon Glass /* assign the requested callback */
1090649cd0dSSimon Glass clbkp = find_env_callback(value);
1100649cd0dSSimon Glass if (clbkp != NULL)
1110649cd0dSSimon Glass #if defined(CONFIG_NEEDS_MANUAL_RELOC)
1120649cd0dSSimon Glass ep->callback = clbkp->callback + gd->reloc_off;
1130649cd0dSSimon Glass #else
1140649cd0dSSimon Glass ep->callback = clbkp->callback;
1150649cd0dSSimon Glass #endif
1160649cd0dSSimon Glass }
1170649cd0dSSimon Glass }
1180649cd0dSSimon Glass
1190649cd0dSSimon Glass return 0;
1200649cd0dSSimon Glass }
1210649cd0dSSimon Glass
on_callbacks(const char * name,const char * value,enum env_op op,int flags)1220649cd0dSSimon Glass static int on_callbacks(const char *name, const char *value, enum env_op op,
1230649cd0dSSimon Glass int flags)
1240649cd0dSSimon Glass {
1250649cd0dSSimon Glass /* remove all callbacks */
1260649cd0dSSimon Glass hwalk_r(&env_htab, clear_callback);
1270649cd0dSSimon Glass
1280649cd0dSSimon Glass /* configure any static callback bindings */
1290649cd0dSSimon Glass env_attr_walk(ENV_CALLBACK_LIST_STATIC, set_callback, NULL);
1300649cd0dSSimon Glass /* configure any dynamic callback bindings */
1310649cd0dSSimon Glass env_attr_walk(value, set_callback, NULL);
1320649cd0dSSimon Glass
1330649cd0dSSimon Glass return 0;
1340649cd0dSSimon Glass }
1350649cd0dSSimon Glass U_BOOT_ENV_CALLBACK(callbacks, on_callbacks);
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