[PATCH] arm: Kconfig: Explain TFABOOT

[Andre Przywara]

The CONFIG_TFABOOT option is more about what U-Boot DOES NOT need to do
than to support some features.

Explain a bit more in the Kconfig help text to avoid misunderstandings.

Signed-off-by: Andre Przywara <andre.przywara at arm.com>
---
 arch/arm/Kconfig | 9 +++++++--
 1 file changed, 7 insertions(+), 2 deletions(-)

diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig
index 8ba73680699..88ed3f2344d 100644
--- a/arch/arm/Kconfig
+++ b/arch/arm/Kconfig
@@ -1797,8 +1797,13 @@ config TFABOOT
 	depends on ARCH_SUPPORT_TFABOOT
 	default n
 	help
-	  Enabling this will make a U-Boot binary that is capable of being
-	  booted via TF-A (Trusted Firmware for Cortex-A).
+	  Some platforms support the setup of secure registers (for instance
+	  for CPU errata handling) or provide secure services like PSCI.
+	  Those services could also be provided by other firmware parts
+	  like TF-A (Trusted Firmware for Cortex-A), in which case U-Boot
+	  does not need to (and cannot) execute this code.
+	  Enabling this option will make a U-Boot binary that is relying
+	  on other firmware layers to provide secure functionality.
 
 config TI_SECURE_DEVICE
 	bool "HS Device Type Support"
-- 
2.17.5