Query regarding uboot and uEnv.txt

Hello All,

I have followed instructions @ https://eewiki.net/display/linuxonarm/BeagleBone+Black
and was successfully able to run it on my beaglebone back vis SD card.

It would be very helpful if could please clarify below doubts:

  1. uEnv.txt:
    I ended up with two versions of uenv.txt
    a. /media/rootfs/ - where uEnv.txt was mentioned under headline “If you don’t want to clear out the old Bootloader in eMMC add this uEnv.txt to /media/rootfs/”
    I am still not sure what this means

b./media/rootfs/boot/uEnv.txt - which contains uname_r=

Can someone please explain me which uEnv.txt does u-boot parses

  1. What needs to be done to connect beaglebone black to internet via usb for this image.

  2. Finally where can I find beginers guide on how u-boot overlay works.

Thanks…

Hello All,

I have followed instructions @
https://eewiki.net/display/linuxonarm/BeagleBone+Black
and was successfully able to run it on my beaglebone back vis SD card.

It would be very helpful if could please clarify below doubts:
1. uEnv.txt:
I ended up with two versions of uenv.txt
a. /media/rootfs/ - where uEnv.txt was mentioned under headline "If you
don't want to clear out the old Bootloader in eMMC add this uEnv.txt to
/media/rootfs/"
I am still not sure what this means

b./media/rootfs/boot/uEnv.txt - which contains uname_r=<my kernel version>

Can someone please explain me which uEnv.txt does u-boot parses

Years and Years ago, when the BeagleBone Black first launched, it
shipped with a bootloader in the eMMC, this looked inside the "first"
partition of the microSD.

We've tried to keep that compatibility where it made sense. And break
it where it made no sense, U-Boot Overlays, BTRFS, etc..

2. What needs to be done to connect beaglebone black to internet via usb for
this image.

That's really up to you... eewiki is setup to 'teach' you how things
are put together, not make a final image for you. We have other
images that do that..

3. Finally where can I find beginers guide on how u-boot overlay works.

well normally you ask questions in this forum, or search the forum..

https://elinux.org/Beagleboard:BeagleBoneBlack_Debian#U-Boot_Overlays

Regards,

Cheers Rob for taking time out to reply…

I would also like to take this opportunity to thank you for all the help and support you are providing to us beginners…
I have solved so many of my queries by seeing your replies in other posts…

Back to where I was…
The whole point of this exercise was to start teaching myself device driver development…
And you are right, I have learned about how the linux distro for embedded systems is created…

Looks like it will be considerable work required to create a proper distro and that is not my target…

So here is the new strategy…
I have downloaded and flash my BBB with latest debian image (Debian 9.3 2018-01-28).

If my understanding is correct then to create loadable modules, I need kernel headers for this…
Could you be kind enough to guide me as where I can get it for Debian 9.3 2018-01-28…

Also a pointer on how to cross compile these loadable modules…

Regards,
Hemant Kapoor

Cheers Rob for taking time out to reply....

I would also like to take this opportunity to thank you for all the help and
support you are providing to us beginners....
I have solved so many of my queries by seeing your replies in other
posts....

Back to where I was....
The whole point of this exercise was to start teaching myself device driver
development....
And you are right, I have learned about how the linux distro for embedded
systems is created....

Looks like it will be considerable work required to create a proper distro
and that is not my target...

So here is the new strategy....
I have downloaded and flash my BBB with latest debian image (Debian 9.3
2018-01-28).

If my understanding is correct then to create loadable modules, I need
kernel headers for this....
Could you be kind enough to guide me as where I can get it for Debian 9.3
2018-01-28....

sudo apt update
sudo apt install linux-headers-`uname -r`

Also a pointer on how to cross compile these loadable modules...

Depends on the module.. Every out of tree driver is different...

Regards,

sudo apt update
sudo apt install linux-headers-uname -r

HK: Above instructions are for building the modules natively correct… This won’t help me cross compiling but based on your second response, it is clear that module are different in terms of compilation than normal application…

So I will stick with compiling modules natively and think of cross compilation later…

Thanks again…

Yeap, cross building is a pain, thus we ship everything in the repo so
users can build on target..

Regards,

So following your suggestion…
I hit my first road block :frowning:

hemant@beaglebone:~$ sudo apt-get install linux-headers-uname -r

Reading package lists... Done Building dependency tree Reading state information... Done You might want to run 'apt --fix-broken install' to correct these. The following packages have unmet dependencies: chromium : Depends: chromium-common (= 60.0.3112.78-1rcnee0~stretch+20170806) but 61.0.3163.100-2rcnee0~stretch+20170927 is to be installed E: Unmet dependencies. Try 'apt --fix-broken install' with no packages (or specify a solution).

Also tried the suggestion and did
sudo apt --fix-broken install
and got below message at the end…

Unpacking chromium (63.0.3239.84-1~deb9u1rcnee0~stretch+20171227) over (60.0.3112.78-1rcnee0~stretch+20170806) .........] dpkg: error processing archive /var/cache/apt/archives/chromium_63.0.3239.84-1~deb9u1rcnee0~stretch+20171227_armhf.deb (--un pack): trying to overwrite '/usr/lib/chromium/natives_blob.bin', which is also in package chromium-common 61.0.3163.100-2rcnee0~st retch+20170927 dpkg-deb: error: subprocess paste was killed by signal (Broken pipe) Errors were encountered while processing: /var/cache/apt/archives/chromium_63.0.3239.84-1~deb9u1rcnee0~stretch+20171227_armhf.deb E: Sub-process /usr/bin/dpkg returned an error code (1)

what image is this?

cat /etc/dogtag ?

Regards,

hemant@beaglebone:~$ cat /etc/dogtag
BeagleBoard.org Debian Image 2017-08-31

Okay thanks i'll take a look at what's getting stuck in that one.

ps, new images were posted last month:

https://beagleboard.org/latest-images

Regards,

Cheers…

I will try the new image tonight and reply the results back

I can confirm that the latest image didn’t have any issues installing kernel headers…

hemant@beaglebone:~$ sudo apt-get install linux-headers-uname -r

Reading package lists... Done Building dependency tree Reading state information... Done The following NEW packages will be installed: linux-headers-4.9.78-ti-r94 0 upgraded, 1 newly installed, 0 to remove and 26 not upgraded. Need to get 10.8 MB of archives. After this operation, 75.0 MB of additional disk space will be used. Get:1 http://repos.rcn-ee.com/debian stretch/main armhf linux-headers-4.9.78-ti-r94 armhf 1stretch [10.8 MB] Fetched 10.8 MB in 4s (2,623 kB/s) Selecting previously unselected package linux-headers-4.9.78-ti-r94. (Reading database ... 34488 files and directories currently installed.) Preparing to unpack .../linux-headers-4.9.78-ti-r94_1stretch_armhf.deb ... Unpacking linux-headers-4.9.78-ti-r94 (1stretch) ... Setting up linux-headers-4.9.78-ti-r94 (1stretch) ...

Thanks…