cmd: env: add env select command

Add the new command 'env select' to force the persistent storage
of environment, saved in gd->env_load_prio.

Signed-off-by: Patrick Delaunay <[email protected]>

cmd/Kconfig

@@ -610,6 +610,11 @@ config CMD_NVEDIT_LOAD
 	  Load all environment variables from the compiled-in persistent
 	  storage.
 
+config CMD_NVEDIT_SELECT
+	bool "env select"
+	help
+	  Select the compiled-in persistent storage of environment variables.
+
 endmenu
 
 menu "Memory commands"

cmd/nvedit.c

@@ -802,6 +802,15 @@ static int do_env_load(struct cmd_tbl *cmdtp, int flag, int argc,
 	return env_reload() ? 1 : 0;
 }
 #endif
+
+#if defined(CONFIG_CMD_NVEDIT_SELECT)
+static int do_env_select(struct cmd_tbl *cmdtp, int flag, int argc,
+			 char *const argv[])
+{
+	return env_select(argv[1]) ? 1 : 0;
+}
+#endif
+
 #endif /* CONFIG_SPL_BUILD */
 
 int env_match(uchar *s1, int i2)
@@ -1367,6 +1376,9 @@ static struct cmd_tbl cmd_env_sub[] = {
 #if defined(CONFIG_CMD_ERASEENV)
 	U_BOOT_CMD_MKENT(erase, 1, 0, do_env_erase, "", ""),
 #endif
+#endif
+#if defined(CONFIG_CMD_NVEDIT_SELECT)
+	U_BOOT_CMD_MKENT(select, 2, 0, do_env_select, "", ""),
 #endif
 	U_BOOT_CMD_MKENT(set, CONFIG_SYS_MAXARGS, 0, do_env_set, "", ""),
 #if defined(CONFIG_CMD_ENV_EXISTS)
@@ -1456,6 +1468,9 @@ static char env_help_text[] =
 #if defined(CONFIG_CMD_NVEDIT_LOAD)
 	"env load - load environment\n"
 #endif
+#if defined(CONFIG_CMD_NVEDIT_SELECT)
+	"env select [target] - select environment target\n"
+#endif
 #if defined(CONFIG_CMD_NVEDIT_EFI)
 	"env set -e [-nv][-bs][-rt][-at][-a][-i addr,size][-v] name [arg ...]\n"
 	"    - set UEFI variable; unset if '-i' or 'arg' not specified\n"

env/env.c

@@ -344,3 +344,45 @@ int env_init(void)
 
 	return ret;
 }
+
+int env_select(const char *name)
+{
+	struct env_driver *drv;
+	const int n_ents = ll_entry_count(struct env_driver, env_driver);
+	struct env_driver *entry;
+	int prio;
+	bool found = false;
+
+	printf("Select Environment on %s: ", name);
+
+	/* search ENV driver by name */
+	drv = ll_entry_start(struct env_driver, env_driver);
+	for (entry = drv; entry != drv + n_ents; entry++) {
+		if (!strcmp(entry->name, name)) {
+			found = true;
+			break;
+		}
+	}
+
+	if (!found) {
+		printf("driver not found\n");
+		return -ENODEV;
+	}
+
+	/* search priority by driver */
+	for (prio = 0; (drv = env_driver_lookup(ENVOP_INIT, prio)); prio++) {
+		if (entry->location == env_get_location(ENVOP_LOAD, prio)) {
+			/* when priority change, reset the ENV flags */
+			if (gd->env_load_prio != prio) {
+				gd->env_load_prio = prio;
+				gd->env_valid = ENV_INVALID;
+				gd->flags &= ~GD_FLG_ENV_DEFAULT;
+			}
+			printf("OK\n");
+			return 0;
+		}
+	}
+	printf("priority not found\n");
+
+	return -ENODEV;
+}

include/env.h

@@ -286,6 +286,13 @@ int env_save(void);
  */
 int env_erase(void);
 
+/**
+ * env_select() - Select the environment storage
+ *
+ * @return 0 if OK, -ve on error
+ */
+int env_select(const char *name);
+
 /**
  * env_import() - Import from a binary representation into hash table
  *
@@ -349,5 +356,4 @@ int env_get_char(int index);
  * This is used for those unfortunate archs with crappy toolchains
  */
 void env_reloc(void);
-
 #endif