[PATCH 4/8] env: mmc: add CONFIG_ENV_MMC_USE_DT

[Patrick Delaunay]

Add a new config CONFIG_ENV_MMC_USE_DT to force configuration of the
U-Boot environment offset with device tree config node.

This patch avoids issues when several CONFIG_ENV_IS_IN_XXX are activated,
the defconfig file uses the same value for CONFIG_ENV_OFFSET or
CONFIG_ENV_OFFSET_REDUND for the several ENV backends (SPI_FLASH, EEPROM
NAND, SATA, MMC).

After this patch a bad offset value is not possible when the selected
partition in device tree is not found.

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

 env/Kconfig | 16 ++++++++++++++++
 env/mmc.c   |  7 +++++++
 2 files changed, 23 insertions(+)

diff --git a/env/Kconfig b/env/Kconfig
index 24111dfaf47b..f8ee99052b97 100644
--- a/env/Kconfig
+++ b/env/Kconfig
@@ -242,6 +242,13 @@ config ENV_IS_IN_MMC
 	  This value is also in units of bytes, but must also be aligned to
 	  an MMC sector boundary.
 
+	  CONFIG_ENV_MMC_USE_DT (optional):
+
+	  These define forces the configuration by the config node in device
+	  tree with partition name: "u-boot,mmc-env-partition" or with
+	  offset: "u-boot,mmc-env-offset", "u-boot,mmc-env-offset-redundant".
+	  CONFIG_ENV_OFFSET and CONFIG_ENV_OFFSET_REDUND are not used.
+
 config ENV_IS_IN_NAND
 	bool "Environment in a NAND device"
 	depends on !CHAIN_OF_TRUST
@@ -650,6 +657,15 @@ config SYS_MMC_ENV_PART
 	  partition 0 or the first boot partition, which is 1 or some other defined
 	  partition.
 
+config ENV_MMC_USE_DT
+	bool "Read partition name and offset in DT"
+	depends on ENV_IS_IN_MMC && OF_CONTROL
+	help
+	  Only use the device tree to get the environment location in MMC
+	  device, with partition name or with offset.
+	  The 2 defines CONFIG_ENV_OFFSET, CONFIG_ENV_OFFSET_REDUND
+	  are not used as fallback.
+
 config USE_DEFAULT_ENV_FILE
 	bool "Create default environment from file"
 	help
diff --git a/env/mmc.c b/env/mmc.c
index 661a268ea07d..1894b6483220 100644
--- a/env/mmc.c
+++ b/env/mmc.c
@@ -26,6 +26,12 @@
 
 #define ENV_MMC_INVALID_OFFSET ((s64)-1)
 
+#if defined(CONFIG_ENV_MMC_USE_DT)
+/* ENV offset is invalid when not defined in Device Tree */
+#define ENV_MMC_OFFSET		ENV_MMC_INVALID_OFFSET
+#define ENV_MMC_OFFSET_REDUND	ENV_MMC_INVALID_OFFSET
+
+#else
 /* Default ENV offset when not defined in Device Tree */
 #define ENV_MMC_OFFSET		CONFIG_ENV_OFFSET
 
@@ -34,6 +40,7 @@
 #else
 #define ENV_MMC_OFFSET_REDUND	ENV_MMC_INVALID_OFFSET
 #endif
+#endif
 
 DECLARE_GLOBAL_DATA_PTR;
 
-- 
2.25.1