env: ext4: add support of command env erase

Add support of opts erase for env in ext4,
this opts is used by command 'env erase'.

This command only fill the env file (CONFIG_ENV_EXT4_FILE)
with 0, the CRC and the saved environment becomes invalid.

Signed-off-by: Patrick Delaunay <patrick.delaunay@st.com>

diff --git a/env/ext4.c b/env/ext4.c
index 0a10a5e..cc36504 100644 (file)
--- a/env/ext4.c
+++ b/env/ext4.c
@@ -99,6 +99,23 @@ static int env_ext4_save(void)
        return 0;
 }
 
+static int env_ext4_erase(void)
+{
+       env_t env_new;
+       int err;
+
+       memset(&env_new, 0, sizeof(env_t));
+
+       err = env_ext4_save_buffer(&env_new);
+       if (err)
+               return err;
+
+       gd->env_valid = ENV_INVALID;
+       puts("done\n");
+
+       return 0;
+}
+
 static int env_ext4_load(void)
 {
        ALLOC_CACHE_ALIGN_BUFFER(char, buf, CONFIG_ENV_SIZE);
@@ -156,4 +173,6 @@ U_BOOT_ENV_LOCATION(ext4) = {
        ENV_NAME("EXT4")
        .load           = env_ext4_load,
        .save           = ENV_SAVE_PTR(env_ext4_save),
+       .erase          = CONFIG_IS_ENABLED(CMD_ERASEENV) ? env_ext4_erase :
+                                                           NULL,
 };