env: Improve ENV_OFFSET help message

When reading Kconfig help messages to understand ENV_OFFSET and
ENV_OFFSET_REDUND, developers may not realise that they need to also
look at the chosen ENV_IS_IN_* options to see how the offsets will be
interpreted.

Signed-off-by: Paul Barker <paul.barker.ct@bp.renesas.com>
Reviewed-by: Simon Glass <sjg@chromium.org>

diff --git a/env/Kconfig b/env/Kconfig
index 67b819d47a227e49a6afa9cb32d51666b4ac5b45..f5f09692332d54e7b9151d89471a3d8821e78a7e 100644 (file)
--- a/env/Kconfig
+++ b/env/Kconfig
@@ -576,7 +576,12 @@ config ENV_OFFSET
        default 0x260000 if ARCH_OMAP2PLUS
        default 0x1080000 if MICROBLAZE && ENV_IS_IN_SPI_FLASH
        help
-         Offset from the start of the device (or partition)
+         Offset from the start of the device (or partition).
+
+         This offset may be interpreted differently depending on the chosen
+         ENV_IS_IN_* options. For example, for ENV_IS_IN_MMC=y, this offset may
+         be negative to indicate an offset backwards from the end of the
+         partition. See the relevant help messages for more details.
 
 config ENV_OFFSET_REDUND
        hex "Redundant environment offset"
@@ -588,6 +593,11 @@ config ENV_OFFSET_REDUND
          Offset from the start of the device (or partition) of the redundant
          environment location.
 
+         This offset may be interpreted differently depending on the chosen
+         ENV_IS_IN_* options. For example, for ENV_IS_IN_MMC=y, this offset may
+         be negative to indicate an offset backwards from the end of the
+         partition. See the relevant help messages for more details.
+
 config ENV_SIZE
        hex "Environment Size"
        default 0x40000 if ENV_IS_IN_SPI_FLASH && ARCH_ZYNQMP