[FE training-materials-updates] Flash filesystem lab update

Michael Opdenacker michael.opdenacker at free-electrons.com
Fri Mar 28 06:32:53 CET 2014

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

On branch  : master
Link       : http://git.free-electrons.com/training-materials/commit/?id=556cf304e27aabf3377a0e6db579665ff49f861a


commit 556cf304e27aabf3377a0e6db579665ff49f861a
Author: Michael Opdenacker <michael.opdenacker at free-electrons.com>
Date:   Fri Mar 28 04:53:36 2014 +0100

    Flash filesystem lab update
    - Correct obsolete comments
    - Try to make instructions clearer
    Signed-off-by: Michael Opdenacker <michael.opdenacker at free-electrons.com>


 .../sysdev-flash-filesystems.tex                   |   24 ++++++++++----------
 1 file changed, 12 insertions(+), 12 deletions(-)

diff --git a/labs/sysdev-flash-filesystems/sysdev-flash-filesystems.tex b/labs/sysdev-flash-filesystems/sysdev-flash-filesystems.tex
index bebfbd3..ae1262a 100644
--- a/labs/sysdev-flash-filesystems/sysdev-flash-filesystems.tex
+++ b/labs/sysdev-flash-filesystems/sysdev-flash-filesystems.tex
@@ -64,7 +64,8 @@ Prepare a JFFS2 filesystem image from the \code{/www/upload/files}
 directory from the previous lab.
 Modify the \code{/etc/init.d/rcS} file to mount a JFFS2 filesystem on
-the seventh flash partition, instead of an ext3 filesystem on the
+the seventh flash partition (we will declare flash partitions in the
+next section), instead of an ext3 filesystem on the
 third MMC disk partition.
 Create a JFFS2 image for your root filesystem, with the same options
@@ -72,23 +73,25 @@ as for the data filesystem.
 \section{MTD partitioning and flashing}
-Memory layout and partitioning can be defined inside kernel sources,
-naturally in the \code{arch/<arch>/<march>/board-<name>.c} since it is
-board dependent. Nevertheless, during device development, it can be
-useful to define partitions at boot time, on the kernel command line.
+Look at the way default flash partitions are defined in the board
+Device Tree sources (\code{arch/arm/boot/dts/omap3-igep0020.dts}).
+However, they do not match the way we wish to rganize our flash storage.
+Therefore, we will define our own partitions at boot time, on the
+kernel command line.
 Enter the U-Boot shell and erase NAND flash, from offset 0x300000,
 up to the end of the NAND flash storage. You'll have to compute the
 remaining size of the flash, from 0x300000 to the end. Remember that
-you can look at U-Boot booting messages to find what is the size of
-the NAND flash.
+you can look at U-Boot booting messages to find what the size of
+the NAND flash is.
 Before flashing JFFS2 images, make sure they will be flashed during
 the software ECC scheme, by running the \code{nandecc sw} command in
-Using the \code{tftp} command, download and flash the kernel image at
-the correct location.
+Using the \code{tftp} command, download and flash the new kernel
+image at the correct location.
 Using the \code{tftp} command, download and flash the JFFS2 image
 of the root filesystem the correct location.
@@ -99,9 +102,6 @@ data filesystem at the correction location.
 Don't forget that you can write U-Boot scripts to automate these
 procedures. This is very handy to avoid mistakes when typing commands!
-Look at the way default MTD partitions are defined in the device tree
-sources: (\code{arch/arm/boot/dts/omap3-igep0020.dts})
 Set the \code{bootargs} variable so that:

More information about the training-materials-updates mailing list