env: Inline env_get_char() into its only user

This function is a relic from the past when environment was read from
underlying device one character at a time.

It is used only in the case when getting an environemnt variable prior
relocation, and the function is simple enough to be inlined there.

Since env_get_char() is being changed to simple access to an array, we
can drop the failing cases and simplify the code (this could have been
done before, since env_get_char() did not fail even before).

Signed-off-by: Marek Behún <marek.behun@nic.cz>
Reviewed-by: Simon Glass <sjg@chromium.org>

cmd/nvedit.c

@@ -706,16 +706,16 @@ char *from_env(const char *envvar)
 	return ret;
 }
 
-static int env_match(uchar *s1, int i2)
+static int env_match(const char *env, const char *s1, int i2)
 {
 	if (s1 == NULL)
 		return -1;
 
-	while (*s1 == env_get_char(i2++))
+	while (*s1 == env[i2++])
 		if (*s1++ == '=')
 			return i2;
 
-	if (*s1 == '\0' && env_get_char(i2-1) == '=')
+	if (*s1 == '\0' && env[i2-1] == '=')
 		return i2;
 
 	return -1;
@@ -726,28 +726,28 @@ static int env_match(uchar *s1, int i2)
  */
 int env_get_f(const char *name, char *buf, unsigned len)
 {
-	int i, nxt, c;
+	const char *env;
+	int i, nxt;
 
-	for (i = 0; env_get_char(i) != '\0'; i = nxt + 1) {
+	if (gd->env_valid == ENV_INVALID)
+		env = (const char *)default_environment;
+	else
+		env = (const char *)gd->env_addr;
+
+	for (i = 0; env[i] != '\0'; i = nxt + 1) {
 		int val, n;
 
-		for (nxt = i; (c = env_get_char(nxt)) != '\0'; ++nxt) {
-			if (c < 0)
-				return c;
+		for (nxt = i; env[nxt] != '\0'; ++nxt)
 			if (nxt >= CONFIG_ENV_SIZE)
 				return -1;
-		}
 
-		val = env_match((uchar *)name, i);
+		val = env_match(env, name, i);
 		if (val < 0)
 			continue;
 
 		/* found; copy out */
 		for (n = 0; n < len; ++n, ++buf) {
-			c = env_get_char(val++);
-			if (c < 0)
-				return c;
-			*buf = c;
+			*buf = env[val++];
 			if (*buf == '\0')
 				return n;
 		}

env/env.c

@@ -166,14 +166,6 @@ static struct env_driver *env_driver_lookup(enum env_operation op, int prio)
 	return drv;
 }
 
-int env_get_char(int index)
-{
-	if (gd->env_valid == ENV_INVALID)
-		return default_environment[index];
-	else
-		return *(uchar *)(gd->env_addr + index);
-}
-
 int env_load(void)
 {
 	struct env_driver *drv;

env/nowhere.c

@@ -31,9 +31,8 @@ static int env_nowhere_init(void)
 static int env_nowhere_load(void)
 {
 	/*
-	 * for SPL, set env_valid = ENV_INVALID is enough as env_get_char()
-	 * return the default env if env_get is used
-	 * and SPL don't used env_import to reduce its size
+	 * For SPL, setting env_valid = ENV_INVALID is enough, as env_get()
+	 * searches default_environment array in that case.
 	 * For U-Boot proper, import the default environment to allow reload.
 	 */
 	if (!IS_ENABLED(CONFIG_SPL_BUILD))

include/env.h

@@ -351,16 +351,6 @@ char *env_get_default(const char *name);
 /* [re]set to the default environment */
 void env_set_default(const char *s, int flags);
 
-/**
- * env_get_char() - Get a character from the early environment
- *
- * This reads from the pre-relocation environment
- *
- * @index: Index of character to read (0 = first)
- * @return character read, or -ve on error
- */
-int env_get_char(int index);
-
 /**
  * env_reloc() - Relocate the 'env' sub-commands
  *