Actions
Forum Thread Details
  • Replies 142 replies
  • Subscribers 64 subscribers
  • Views 23845 views
  • Users 0 members are here
Related

[How-to] BB-View on latest Debian

compeoree

I thought some others might like to know how to get the BB-View working under the latest Debian beta images.

 

Unfortunately, you are going to have to recompile the Kernel. The video works fine without a recompile (the red/blue swap is easy to fix), but the touchscreen control connections are not the same as the standard TI 4-wire interface. I tried to patch the ti_am335x_tsc.c file, so the changes would be limited to a dts recompile, but I haven't been able to get that working yet (I'm pretty sure it is a state machine / bit assignment issue). But anyway, here are the steps that you need to perform.....

 

Overview

1) Download the necessary files

     a) Robert Nelson's handy tools for compiling the Beaglebone kernel

     b) BB-View source for Angstrom

2) Build the default kernel

3) Patch the Kernel and perform a fast recompile

4) Copy the new kernel to the Beaglebone

5) Edit the xorg.conf file to correct the Red/Blue color swap

6) Revel in the 4 days you just saved image

 

Let's Get Started

I am using Ubuntu 12.04 LTS 64 bit running in a VirtualBox VM to compile the kernel:

Make a new folder called bb-view, this is where our build will happen.

> mkdir bb-view

> cd bb-view

 

Install git, if you haven't already:

> apt-get install git

 

Clone Robert Nelson's linux-dev project locally. Be prepared for a large download (~100 Mb for the cross-compiler and ~700 Mb for the kernel source).

> git clone https://github.com/RobertCNelson/linux-dev.git

 

Change into the new linux-dev folder and select branch/tag that matches the Debian version.

> cd linux-dev

> git checkout 3.8.13-bone37 -b tmp

 

Now we need to build the base image, so our cape drivers folder gets populated. The script will tell you if you need to do or install anything else.

> ./build_kernel.sh

 

Come back in an hour or so.....(You might want to download the Angstrom source from element14 now)

 

Patching the Kernel

Extract two files from the Angstrom source:

> unzip angstrom-source.zip

> tar -zxf bb-black-kernel-3.8.13-bb-view.tar.bz2

> cp ./kernel/kernel/drivers/input/touchscreen/ti_am335x_tsc.c  ~/bb-view/linux-dev/KERNEL/drivers/input/touchscreen/

> cp ./kernel/kernel/firmware/capes/BB-VIEW-LCD7-01-00A0.dts  ~/bb-view/linux-dev/KERNEL/firmware/capes/

 

Now we need to let the compiler know that we want to add the firmware to the build:

> nano   ~/bb-view/linux-dev/KERNEL/firmware/Makefile

 

Add the following line somewhere near line 192 (CTRL-C will display current cursor position):

BB-VIEW-LCD7-01-00A0.dtbo \

 

Don't forget the trailing backslash....it is important. Now save and exit by doing CTRL-O, Enter, CTRL-X.

Change back to the linux-dev root folder:

> cd   ~/bb-view/linux-dev

 

Now issue the kernel rebuild command, this won't take very long at all:

> ./tools/rebuild.sh

 

 

Copy Kernel to BBB

The following instructions assume that you already have the Debian beta installed and booted up on the BBB.

The easiest way is to copy the files over the network, via the 'scp' command:

> scp   ~/bb-view/linux-dev/deploy/3.8.13-bone37.zImage   debian@192.168.7.2:/home/debian

Replace debian (both instances) with the username you are running on the BBB and 192.168.7.2 with the IP address of the BBB.

 

Now log into the BBB and copy the kernel image to the boot partition:

> ssh debian@192.168.7.2

bbb>  sudo cp 3.8.13-bone37.zImage   /boot/uboot/zImage

 

We need to do one more thing before the LCD will work. Since the cape doesn't have an EEPROM, we need to black-list the HDMI drivers and force-load the BB-VIEW drivers in the boot command file:

bbb>  sudo  nano  /boot/uboot/uEnv.txt

 

Find the "optargs" line and edit it to be:

optargs=capemgr.disable_partno=BB-BONELT-HDMI,BB-BONELT-HDMIN  capemgr.enable_partno=BB-VIEW-LCD7-01

Notice that the preceding "#" has been removed. You don't want to disable BB-BONE-EMMC-2G, or you won't be able to boot from eMMC.

Now save and exit by doing CTRL-O, Enter, CTRL-X.

 

Reboot the BBB and the LCD should now work....except the blue and red are reversed.

 

Fixing Red/Blue Color Swap

This is due to errata in the TI AM335x processor when switching between 16 and 24 bit video modes. To fix this, we must first find the name of our screen:

> ssh debian@192.168.7.2

bbb> cat  /var/log/Xorg.0.log  |  grep  screen

Mine was "Builtin Default fbdev Screen 0"

 

Now we edit our X configuration file:

bbb> sudo nano  /usr/share/X11/xorg.conf.d/10-evdev.conf

 

and add a "Screen" section at the end of the file:

Section "Screen"

        Identifier "Builtin Default fbdev Screen 0"

        Monitor "Configured Monitor"

        Device "Configured Video Device"

        DefaultDepth 24

EndSection

Save and exit by doing CTRL-O, Enter, CTRL-X.

Reboot and enjoy!

Parents

  • I'm using the ARMHF debian image from BeagleBone Black | armhf.com .

    The latest ARMHF image use 3.14.4.1 kernel.

     

    How can I get the touchscreen BB-View working in my BBB ?

    What GIT command should I exec to get the  right kernel?

     

    Have you tried?

     

     

    Thanks

  • in reply to Former Member

    Thnaks,

    the problem is that I get the kernel with:

         git checkout 3.14.4-bone4 -b tmp  (I hope it's right!)

    and after the build_kernel.sh command I can't find firmware/capes folder where to put BB-VIEW-LCD7-01-00A0.dts file .

  • in reply to Former Member

    unfortunately that checkout command is meaningless without knowing what the source repo is.

     

    Note that Louis original instructions were for 3.8.x kernel, they most likely won't work for 3.14 at all. Too much has changed.

    It also seems that Robert has changed the repo mentioned in Louis post, so neither the original instructions nor your attempted checkout of 3.14.4-bone4 will work as those branches are not in the source repo.

     

    3.14 also does not include capemgr, or device tree overlays, so what's described cannot function on 3.14 - this is why there's no firmware/capes directory, that concept simply doesn't exist in a 3.14 generation kernel.

     

    The capemgr/devicetree overlay stuff isn't going to exist on any kernel other than the BBB specific 3.8.x, this is simply because nobody seems willing to work on it. While there's been some efforts around devicetree overlays for more recent kernels, you should expect any future implementation (should it ever appear) to be significantly different from the 3.8.x one, which again means that the instructions here won't apply directly or cleanly, you'll have to work out the details of the differences yourself.

     

    To get this working on 3.14 you have a lot of work ahead of you. You'll have to manually merge the driver changes to start with, and then you'll have to manually merge the appropriate parts of the overlay into the static devicetree and then build the result.  There's no easy way, since nobody else seems to have done it for you.

  • in reply to Former Member

    Thanks a lot. You were very clear.

     

    What do you thinks about using the 3.8.x kernel (with BB-View driver) in the latest ARMHF image putting the kernel on it?

  • in reply to Former Member

    It's theoretically possible to use Roberts 3.8.x kernel with Louis' modifications for BB-View on that armhf.com image, but what's the point?  You could just as easily use Roberts official (as shipping on the Rev C boards) debian image which seems likely to have most of it done for you. The commit I pointed out earlier was from Robert adding BB-View support to the official kernel...

     

    I can't really help you much more here as I don't use either the armhf.com image or the official images myself.

  • in reply to Former Member

    I think you are right, I'll probably use official image.

    The only reason why I'd like to use armhf images is that it's minimal and clean to start developing dedicated applications without the need to disable X server, Web server etc...

     

    Thanks for your help!

  • in reply to Former Member

    In which case, use Roberts 'small flash' filesystem - debian-7.5-bare-armhf-2014-05-07.tar.xz - from http://www.eewiki.net/display/linuxonarm/BeagleBone+Black or perhaps even the minimal one if you don't want to spend lots of time working out how to add all the missing parts to the bare one.

    Those are what Robert uses as the starting point for the official images.

     

    The problem with all of the alternative images is that somewhere you're going to have to spend time working out how to get something working. It might be the BB-View, it might be basic networking on Roberts bare filesystem, it might be disabling X server on the full image.  However it's likely that the official images will have the widest possible cape support.

Reply
  • in reply to Former Member

    In which case, use Roberts 'small flash' filesystem - debian-7.5-bare-armhf-2014-05-07.tar.xz - from http://www.eewiki.net/display/linuxonarm/BeagleBone+Black or perhaps even the minimal one if you don't want to spend lots of time working out how to add all the missing parts to the bare one.

    Those are what Robert uses as the starting point for the official images.

     

    The problem with all of the alternative images is that somewhere you're going to have to spend time working out how to get something working. It might be the BB-View, it might be basic networking on Roberts bare filesystem, it might be disabling X server on the full image.  However it's likely that the official images will have the widest possible cape support.

Children
No Data