[FE training-materials-updates] Document BBB flashing system limitations

[Michael Opdenacker]

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

On branch  : master
Link       : http://git.free-electrons.com/training-materials/commit/?id=f313145874645b8b5f26d1d39b42cc74b509de26

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commit f313145874645b8b5f26d1d39b42cc74b509de26
Author: Michael Opdenacker <michael.opdenacker at free-electrons.com>
Date:   Tue May 27 11:45:45 2014 +0200

    Document BBB flashing system limitations
    
    Signed-off-by: Michael Opdenacker <michael.opdenacker at free-electrons.com>


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f313145874645b8b5f26d1d39b42cc74b509de26
 .../linux/bootloader/beaglebone-black/README.txt   |   12 ++++++++++++
 1 file changed, 12 insertions(+)

diff --git a/lab-data/linux/bootloader/beaglebone-black/README.txt b/lab-data/linux/bootloader/beaglebone-black/README.txt
index 61c9946..50ab63d 100644
--- a/lab-data/linux/bootloader/beaglebone-black/README.txt
+++ b/lab-data/linux/bootloader/beaglebone-black/README.txt
@@ -99,6 +99,18 @@ available either.
 Should you need more standard tools, you may boot the board with
 an MMC card with Debian on it (see http://beagleboard.org/latest-images).
 
+Limitations
+-----------
+
+- The system does not erase the previous U-Boot environment that would
+  remain from an earlier session.
+  How to do it safely from Linux without damaging existing partitions? 
+
+- The system cannot cope with broken partition tables that are
+  not suitable with booting on the first partition with U-Boot.
+  In case the partition table needs fixing, do it from Debian booted
+  from MMC.
+
 ===============================
 How the binaries where compiled
 ===============================