Enable dmesg messages and USB

[ricardojlrufino]

Hi, I tested your image and it works right now congratulations.

I am trying to enable some features little by little, and I am having difficulties. I was unable to make the logs work so it is very difficult to debug.

Can you help me ?

[furkantokac]

Sure.

You can find the disabled kernel configurations from reference [0].

For more detailed info, I suggest you to compare original kernel defconfig (which is bcm2709_defconfig) and my fastboot kernel defconfig[1]. You can find the original kernel defconfig from reference [2], but it doesn't have same styling with my kernel defconfig so it is hard to compare side by side. To obtain an original kernel defconfig with the same style of my kernel defconfig, just compile my fastboot defconfig[3] with the parameter BR2_LINUX_KERNEL_DEFCONFIG="bcm2709" instead of BR2_LINUX_KERNEL_CUSTOM_CONFIG_FILE="board/ftdev/rpi3/custom_files/kernel-fastboot.config", then save linux defconfig and compare them easily.

References
[0] disabled kernel debug configurations
https://github.com/furkantokac/buildroot/blob/ftdev/board/ftdev/rpi3/docs/distro_optimization/fcond04/README.config

[1] fastboot kernel defconfig
https://github.com/furkantokac/buildroot/blob/ftdev/board/ftdev/rpi3/custom_files/kernel-fastboot.config

[2] original kernel defconfig
https://github.com/raspberrypi/linux/blob/c117a8bccf37bfba323065b566cf999ed4629a4a/arch/arm/configs/bcm2709_defconfig

[3] fastboot defconfig
https://github.com/furkantokac/buildroot/blob/ftdev/configs/ftdev_rpi3_fastboot_defconfig

[ricardojlrufino]

I don't know if I followed the instructions correctly, but in the test I did, I didn't find the differences I was looking for (related to debug log and USB)
My changes:
diff configs/ftdev_rpi3_fastboot_defconfig configs/ftdev_rpi3_fastboot_v2_defconfig

16,17c16
< BR2_LINUX_KERNEL_USE_CUSTOM_CONFIG=y
< BR2_LINUX_KERNEL_CUSTOM_CONFIG_FILE="board/ftdev/rpi3/custom_files/kernel-fastboot.config"
---
> BR2_LINUX_KERNEL_DEFCONFIG="bcm2709"

I saw that the .config of the root folder has "no differences".
As I understand it the difference will be in, [1], right ?!:
[1] output/build/linux-c117a8bccf37bfba323065b566cf999ed4629a4a/.config

Comparing the before and after, USB remains disabled

I took the settings below from 'raspberrypi3_defconfig' to test
diff configs/ftdev_rpi3_fastboot_defconfig configs/ftdev_rpi3_fastboot_v3_defconfig

13,17c13,15
< BR2_LINUX_KERNEL_CUSTOM_GIT=y
< BR2_LINUX_KERNEL_CUSTOM_REPO_URL="https://github.com/raspberrypi/linux.git"
< BR2_LINUX_KERNEL_CUSTOM_REPO_VERSION="c117a8bccf37bfba323065b566cf999ed4629a4a"
< BR2_LINUX_KERNEL_USE_CUSTOM_CONFIG=y
< BR2_LINUX_KERNEL_CUSTOM_CONFIG_FILE="board/ftdev/rpi3/custom_files/kernel-fastboot.config"
---
> BR2_LINUX_KERNEL_CUSTOM_TARBALL=y
> BR2_LINUX_KERNEL_CUSTOM_TARBALL_LOCATION="$(call github,raspberrypi,linux,83b36f98e1a48d143f0b466fcf9f8c4e382c9a1c)/linux-83b36f98e1a48d143f0b466fcf9f8c4e382c9a1c.tar.gz"
> BR2_LINUX_KERNEL_DEFCONFIG="bcm2709

This make impossible to compare like you said

[ricardojlrufino]

running make defconfig-save in linux kernel folder improved the compare results, but
a series of new questions were asked, which I did not know how to answer ... = /

[ricardojlrufino]

I was able to enable logs, thanks to your help.
Thank you very much

I found this error enabling QT

>>> qt5declarative 5.11.3 Installing to target
cp -dpf /opt/builds/buildroot-rasp3/output/host/arm-buildroot-linux-gnueabihf/sysroot/usr/bin/qml* /opt/builds/buildroot-rasp3/output/target/usr/bin
cp -dpfr /opt/builds/buildroot-rasp3/output/host/arm-buildroot-linux-gnueabihf/sysroot/usr/qml /opt/builds/buildroot-rasp3/output/target/usr
cp -dpf /opt/builds/buildroot-rasp3/output/host/arm-buildroot-linux-gnueabihf/sysroot/usr/lib/libQt5Qml*.so.* /opt/builds/buildroot-rasp3/output/target/usr/lib
cp -dpfr /opt/builds/buildroot-rasp3/output/host/arm-buildroot-linux-gnueabihf/sysroot/usr/lib/qt/plugins/qml* /opt/builds/buildroot-rasp3/output/target/usr/lib/qt/plugins
cp -dpf /opt/builds/buildroot-rasp3/output/host/arm-buildroot-linux-gnueabihf/sysroot/usr/lib/libQt5Quick*.so.* /opt/builds/buildroot-rasp3/output/target/usr/lib
cp: não foi possível obter estado de '/opt/builds/buildroot-rasp3/output/host/arm-buildroot-linux-gnueabihf/sysroot/usr/lib/libQt5Quick*.so.*': Arquivo ou diretório inexistente
package/pkg-generic.mk:331: recipe for target '/opt/builds/buildroot-rasp3/output/build/qt5declarative-5.11.3/.stamp_target_installed' failed
make: *** [/opt/builds/buildroot-rasp3/output/build/qt5declarative-5.11.3/.stamp_target_installed] Error 1

tried with version 5.6, but also got errors ..

For me the qt5declarative already has this library internally
./output/build/qt5declarative-5.11.3/include/QtQuick/5.11.3/

I couldn't find any way out of this error, can you give me a direction

[ricardojlrufino]

after a rebuild its works

• delete qt5 folders
• make qt5declarative-reconfigure

[furkantokac]

I highly recommend you to compile qt-everywhere yourself statically, independent from the Buildroot. I share my script that does the job. Just compile your buildroot, put the script in the same directory that has your compiled "buildroot" directory, change the Qt version however you want and run the script it. It will do everything for you.

Edit : Go to Issue https://github.com/furkantokac/buildroot/issues/2 for the script.

[furkantokac]

If you got any problem about Qt, please open a new issue.

[ricardojlrufino]

amazing, thanks, I will test

[furkantokac]

No problem. It will be great if you can report the result to this issue : https://github.com/furkantokac/buildroot/issues/2

[magnock]

Thanks @furkantokac for all theses details.
@ricardojlrufino, can you please explain how did you managed to enable USB ? I need to do the same for Network / WLAN. What config did you add to kernel-fastboot.config ? Thx

[furkantokac]

@magnock USB and network is disabled from the kernel. You can just enable them by make linux-xconfig. See what options are disabled from here : https://github.com/furkantokac/buildroot/tree/ftdev/board/ftdev/rpi3/docs/distro_optimization/fcond04

[magnock]

Thanks @furkantokac.
If I run “make linux-xconfig”, I‘ll get all other default stuff in kernel. I just need to patch your kernel-fastboot.config with USB and NETWORK.

If I add "CONFIG_NET=y" and "CONFIG_USB_SUPPORT=y" to kernel-fastboot.config and run “make ftdev_rpi3_fastboot_defconfig”, do I expect to have your 1.75s booting img with USB and NETWORK ? (it will be more that 1.75, I know :) )

[furkantokac]

@magnock

If I run “make linux-xconfig”, I‘ll get all other default stuff in kernel. I just need to patch your kernel-fastboot.config with USB and NETWORK.

1. make ftdev_rpi3_fastboot_defconfig
2. make linux-xconfig

You should make the ftdev_rpi3_fastboot_defconfig first, then when you make the linux-xconfig, you'll see the settings of ftdev_rpi3_fastboot_defconfig's kernel.

If I add "CONFIG_NET=y" and "CONFIG_USB_SUPPORT=y" to kernel-fastboot.config

I don't really recommend directly editing the kernel-fastboot.config since some configurations depens on each other.

do I expect to have your 1.75s booting img with USB and NETWORK ?

The short answer is yes, if you just enable them without doing any extra work, they should slowdown the boot process. But you can optimize them and go below the 1.75sec. There is no limit of optimization :)

Network connection is directly related to userspace like you need some work for network connection after the kernel loaded so even if you have support them from the kernel, you have to optimize the network connection process. For example, the easiest thing you can do is delaying the connection process. It appearently requires some work if your issue is fastboot.

For the USB connection, kind of same. Like external connections always requires some kind of polling, and if the issue is fastboot, it requires some work according to your requirements. For example, my requirement is running a Qt application that reads data from UART so till the Qt application runs and I receive the UART data, I don't consider the boot process is finished. If this requirement includes USB device connection and network connection, it requires another work.

I'll create an another defconfig that supports USB connection soon, without an optimization. I'll ping here when I'm done. On the long term, I'm planning to work on fastboot + USB + Networking since its the most common usecase and will be good for non-technical people.

If you have any question, please don't hesitate to ask.