[FE training-materials-updates] labs/buildroot-basic: instruct people to reset the U-Boot environment if needed

[Boris Brezillon]

Repository : git://git.free-electrons.com/training-materials.git

On branch  : mtd-rework-WIP
Link       : http://git.free-electrons.com/training-materials/commit/?id=21788d4593fbfbee053fe9d9eb7bbcb85db8e4c3

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commit 21788d4593fbfbee053fe9d9eb7bbcb85db8e4c3
Author: Thomas Petazzoni <thomas.petazzoni at free-electrons.com>
Date:   Tue May 12 15:37:01 2015 +0200

    labs/buildroot-basic: instruct people to reset the U-Boot environment if needed
    
    Signed-off-by: Thomas Petazzoni <thomas.petazzoni at free-electrons.com>


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21788d4593fbfbee053fe9d9eb7bbcb85db8e4c3
 labs/buildroot-basic/buildroot-basic.tex | 12 ++++++++++++
 1 file changed, 12 insertions(+)

diff --git a/labs/buildroot-basic/buildroot-basic.tex b/labs/buildroot-basic/buildroot-basic.tex
index d872d5c..7dc3ce8 100644
--- a/labs/buildroot-basic/buildroot-basic.tex
+++ b/labs/buildroot-basic/buildroot-basic.tex
@@ -385,6 +385,18 @@ same check for the Linux kernel.
 
 Login as \code{root} on the BeagleBone Black, and explore the system.
 
+Note: if your system doesn't boot as expected, make sure to reset the
+U-Boot environment by running the following U-Boot commands:
+
+\begin{verbatim}
+env default -f -a
+saveenv
+\end{verbatim}
+
+and reset. This is needed because the U-Boot loaded from the SD card
+still loads the U-Boot environment from the eMMC. Ask your instructor
+for additional clarifications if needed.
+
 \section{Explore the build log}
 
 Back to your build machine, since we redirected the build output to a