From 0718f7432749af284828e22b0934366244c3ad62 Mon Sep 17 00:00:00 2001
From: Patrick Delaunay <patrick.delaunay@st.com>
Date: Tue, 28 Jul 2020 11:51:26 +0200
Subject: [PATCH] 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>
---
 env/ext4.c | 19 +++++++++++++++++++
 1 file changed, 19 insertions(+)

diff --git a/env/ext4.c b/env/ext4.c
index 0a10a5e050..cc36504154 100644
--- 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,
 };