[Buildroot] [git commit branch/2026.02.x] boot/uboot: improve U-Boot OP-TEE TEE format options help text

[Thomas Perale]

commit: https://gitlab.com/buildroot.org/buildroot/-/commit/ea69fbb1ad84c7523417ff5f1e0a68545152e27a
branch: https://gitlab.com/buildroot.org/buildroot/-/tree/2026.02.x

OP-TEE generates a few binaries that can be used by u-boot on some
platforms (Rockchip, Texas Instruments K3) using TEE variable.

Add a link to the OP-TEE documentation were we can find easily the
desciption for each TEE format that can be used by u-boot.

For convenience, copy tee.elf and tee.bin description in each option
choice help text.

Signed-off-by: Romain Naour <romain.naour at smile.fr>
Signed-off-by: Julien Olivain <ju.o at free.fr>
(cherry picked from commit a5f5c08dcd34452023cbf79ea30071828fb66c1a)
Signed-off-by: Thomas Perale <thomas.perale at mind.be>
---
 boot/uboot/Config.in | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/boot/uboot/Config.in b/boot/uboot/Config.in
index 47ce24ee76..17b7f95f50 100644
--- a/boot/uboot/Config.in
+++ b/boot/uboot/Config.in
@@ -295,15 +295,23 @@ choice
 	  Since this version, the TEE in binary format must be used as
 	  it contains important meta-data.
 
+	  https://optee.readthedocs.io/en/4.9.0/architecture/porting_guidelines.html#binaries
+
 config BR2_TARGET_UBOOT_NEEDS_OPTEE_TEE_ELF
 	bool "tee.elf"
 	help
+	  The main OP-TEE ELF file. All other OP-TEE binaries are
+	  created with this as input.
+
 	  ELF format may be used only for OP-TEE versions before
 	  3.8.0.
 
 config BR2_TARGET_UBOOT_NEEDS_OPTEE_TEE_BIN
 	bool "tee.bin"
 	help
+	  The original OP-TEE binary with a header (v1) and combined
+	  init, paged, and unpaged parts.
+
 	  Binary format must be used for OP-TEE versions since 3.8.0.
 
 endchoice