[U-Boot] [PATCH] pico-imx7d: Add "how to boot with NXP 4.1 Kernel"

[Vanessa Maegima]

The NXP 4.1 kernel needs to boot with secure boot.

Add information on how to enable secure boot mode.

Signed-off-by: Vanessa Maegima <vanessa.maegima at nxp.com>
---
 board/technexion/pico-imx7d/README | 17 +++++++++++++++++
 1 file changed, 17 insertions(+)

diff --git a/board/technexion/pico-imx7d/README b/board/technexion/pico-imx7d/README
index a2805ee..8af4eff 100644
--- a/board/technexion/pico-imx7d/README
+++ b/board/technexion/pico-imx7d/README
@@ -47,3 +47,20 @@ Remove power from the pico board.
 Put pico board into normal boot mode.
 
 Power up the board and the new updated U-Boot should boot from eMMC.
+
+Building U-Boot to boot with NXP 4.1 kernel:
+
+The NXP 4.1 kernel boots only in secure boot mode on mx7.
+
+Follow the next steps to enable secure boot:
+
+$ make mrproper
+$ make pico-imx7d_defconfig
+$ make menuconfig
+	-> ARM architecture
+	-> [*] Enable support for booting in non-secure mode
+	-> [*]   Boot in secure mode by default
+	-> Exit
+$ make
+
+Flash u-boot.imx using the imx_usb_loader tool.
-- 
2.7.4