env: Initialise all the environments

Since we want to have multiple environments, we will need to initialise
all the environments since we don't know at init time what drivers might
fail when calling load.

Let's init all of them, and only consider for further operations the ones
that have not reported any errors at init time.

Reviewed-by: Simon Glass <sjg@chromium.org>
Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>

env/env.c

@@ -64,6 +64,23 @@ static enum env_location env_locations[] = {
 
 static enum env_location env_load_location = ENVL_UNKNOWN;
 
+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
@@ -145,6 +162,9 @@ int env_get_char(int index)
 		if (!drv->get_char)
 			continue;
 
+		if (!env_has_inited(drv->location))
+			continue;
+
 		ret = drv->get_char(index);
 		if (!ret)
 			return 0;
@@ -167,6 +187,9 @@ int env_load(void)
 		if (!drv->load)
 			continue;
 
+		if (!env_has_inited(drv->location))
+			continue;
+
 		printf("Loading Environment from %s... ", drv->name);
 		ret = drv->load();
 		if (ret)
@@ -192,6 +215,9 @@ int env_save(void)
 		if (!drv->save)
 			continue;
 
+		if (!env_has_inited(drv->location))
+			continue;
+
 		printf("Saving Environment to %s... ", drv->name);
 		ret = drv->save();
 		if (ret)
@@ -213,14 +239,10 @@ int env_init(void)
 	int prio;
 
 	for (prio = 0; (drv = env_driver_lookup(ENVOP_INIT, prio)); prio++) {
-		if (!drv->init)
-			continue;
-
-		ret = drv->init();
-		if (!ret)
-			return 0;
+		if (!drv->init || !(ret = drv->init()))
+			env_set_inited(drv->location);
 
-		debug("%s: Environment %s failed to init (err=%d)\n", __func__,
+		debug("%s: Environment %s init done (ret=%d)\n", __func__,
 		      drv->name, ret);
 	}
 

include/asm-generic/global_data.h

@@ -50,6 +50,7 @@ typedef struct global_data {
 #endif
 	unsigned long env_addr;		/* Address  of Environment struct */
 	unsigned long env_valid;	/* Environment valid? enum env_valid */
+	unsigned long env_has_init;	/* Bitmask of boolean of struct env_location offsets */
 
 	unsigned long ram_top;		/* Top address of RAM used by U-Boot */
 	unsigned long relocaddr;	/* Start address of U-Boot in RAM */