# [FE training-materials-updates] Fix a bunch of things in the new board lab

Maxime Ripard maxime.ripard at free-electrons.com
Mon May 19 12:03:22 CEST 2014

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

On branch  : master

>---------------------------------------------------------------

commit 2154b470ddbfed44456d0498e7c51340aa9204f2
Author: Maxime Ripard <maxime.ripard at free-electrons.com>
Date:   Thu May 15 16:58:48 2014 +0200

Fix a bunch of things in the new board lab

Signed-off-by: Maxime Ripard <maxime.ripard at free-electrons.com>

>---------------------------------------------------------------

2154b470ddbfed44456d0498e7c51340aa9204f2
labs/android-new-board/android-new-board.tex |   15 ++++++++++-----
1 file changed, 10 insertions(+), 5 deletions(-)

diff --git a/labs/android-new-board/android-new-board.tex b/labs/android-new-board/android-new-board.tex
index d0b04a3..4227aa2 100644
--- a/labs/android-new-board/android-new-board.tex
+++ b/labs/android-new-board/android-new-board.tex
@@ -41,7 +41,7 @@ then configuring the build system to use that binary.
So, the first step is to download the kernel. Once again, we can use
repo for that. Make it fetch the kernel from
\code{git://gitorious.org/rowboat/kernel.git}, at revision
-\sloppy{\mbox{\code{rowboat-am335x-kernel-3.2}}}, in the \code{kernel} directory.
+\code{rowboat-am335x-kernel-3.2}, in the \code{kernel} directory.

Once done, make \code{repo} download it, and we can start building our
kernel. This time, you'll need to use the \code{am335x_evm_android}
@@ -58,7 +58,8 @@ To do so, we need a few things. First we need to move the
Then, we need to tell Android that it will need to generate a
\code{boot.img} with the brand new kernel we have. This is done
through the \code{TARGET_NO_KERNEL} variable. Obviously, this will
-need to be disabled.
+need to be disabled. You can find where this variable is defined using
+\code{grep}.

In order for Android to be able to properly generate the boot image,
it also needs to know to which base address and which command line it
@@ -72,6 +73,8 @@ boot traces on the serial link, we need to set it to
console=ttyO0,115200n8 androidboot.console=ttyO0
\end{verbatim}

+You also need to change \code{BOARD_KERNEL_BASE} to \code{0x80008000}.
+
Finally, we need to inform the Android build system of where our
actual image is. The \code{mkbootimg} tool is actually looking for a
file called \code{kernel} in the build directory, and it's up to the
@@ -253,10 +256,9 @@ commands:

\begin{verbatim}
export TARGET_PRODUCT=beagleboneblack
-export OMAPES=4.x
export ANDROID_ROOT_DIR=<path/to/android/source>

-make
+make OMAPES=4.x W=1
make install
\end{verbatim}

@@ -283,7 +285,10 @@ controls until you find the values that are working.

To make those changes permanently, you will have to edit the kernel
code. The used PWM is defined is the \code{am335xevm} board file, in
-the \code{arch/arm/mach-omap2} folder.
+the \code{arch/arm/mach-omap2} folder. The PWM work by switching on
+and off at a fast pace the power supply to be able to adjust the
+average voltage delivered between 0 and the actual voltage of the
+line. Increase the period by a factor of 100.

Once you're done, rebuild the kernel, boot it, and you should be able