Commit bb60ad9b authored by Yann E. MORIN's avatar Yann E. MORIN Committed by Thomas Petazzoni
Browse files

boards/raspberrypi: update readme with Device Tree instructions 



Signed-off-by: default avatar"Yann E. MORIN" <yann.morin.1998@free.fr>
Signed-off-by: default avatarThomas Petazzoni <thomas.petazzoni@free-electrons.com>
parent 23da43ae

board/raspberrypi/readme.txt

+27 −4
Original line number Diff line number Diff line
@@ -23,6 +23,10 @@ work on this defconfig: 


  $ make raspberrypi_defconfig



Alternatively, if you want to test support for the Device Tree:



  $ make raspberrypi_dt_defconfig



If you want to use a persistent rootfs, skip to "Build the rootfs", below.



For a volatile rootfs, you have to slightly adjust the configuration:
@@ -51,17 +55,23 @@ Result of the build 
After building, you should obtain this tree:



    output/images/

    +-- rootfs.tar

    +-- rpi-firmware

    +-- rootfs.tar                              [0]

    +-- rpi-firmware/

    |   +-- bcm2708-rpi-b.dtb                   [1]

    |   +-- bcm2708-rpi-b-plus.dtb              [1]

    |   +-- bootcode.bin

    |   +-- config.txt

    |   +-- fixup.dat

    |   `-- start.elf

    `-- zImage



Note for Volatile: rootfs.tar will only be there if you kept

[0] Note for Volatile: rootfs.tar will only be there if you kept

    "tar the root filesystem" option selected in "Filesystem images".



[1] The DTBs (Device Tree Blobs) will only be present if you setup

    Buildroot to install the DTBs from the rpi-firmware package, and

    will only be used if your kernel has support for the Device Tree.



Prepare you SDCard

==================
@@ -89,17 +99,30 @@ Install the binaries to the SDCard 
At the root of the boot partition, the RaspberryPi must find the following

files:



    * bcm2708-rpi-b.dtb         [2]

    * bcm2708-rpi-b-plus.dtb    [2]

    * bootcode.bin

    * config.txt

    * fixup.dat

    * start.elf

    * zImage



[2] Only needed if your kernel has support for the Device Tree.



For example:



 $ cp output/images/rpi-firmware/* /mnt/mountpointboot



If your kernel does *not* have support for the Device Tree, then install

it with:



 $ cp output/images/zImage /mnt/mountpointboot



If your kernel *does* have support for the Device Tree, then install it

with:



  $ ./output/host/usr/bin/mkknlimg output/images/zImage /mnt/mountpointboot/zImage



Note: The kernel image file name is defined in config.txt like this:

kernel=zImage