doc: board: ti: am335x_evm: Add documentation

Link: https://lore.kernel.org/u-boot/20250829191830.GZ124814@bill-the-cat/
Add documentation for config changes required to enable Falcon SD-FAT boot.

Signed-off-by: Sidharth Seela <sidharthseela@gmail.com>
Cc: Tom Rini <trini@konsulko.com>

diff --git a/doc/board/ti/am335x_evm.rst b/doc/board/ti/am335x_evm.rst
index 7a3125d705b7879d7e63edd416148bd45d0eda1b..40e144948a3001e1c0863c3bb16e8fad7a52acfc 100644 (file)
--- a/doc/board/ti/am335x_evm.rst
+++ b/doc/board/ti/am335x_evm.rst
@@ -354,6 +354,16 @@ first.
 Falcon Mode: FAT SD cards
 -------------------------
 
+Compile with additional changes in config variables in menuconfig:
+
+::
+
+   CONFIG_SPL_LEGACY_IMAGE_FORMAT=y # to support non-FIT images
+   CONFIG_LEGACY_IMAGE_FORMAT=y # if commented then SPL Legacy support stops
+   # CONFIG_SPL_ENV_IS_NOWHERE is not set
+   CONFIG_SPL_ENV_IS_IN_FAT=y
+
+
 In this case the additional file is written to the filesystem.  In this
 example we assume that the uImage and device tree to be used are already on
 the FAT filesystem (only the uImage MUST be for this to function