Kernel 3.12.6

[sbp]

hi bmarkus.

First of all - merry Christmas to you, and thank you for your continued support and work on the piCore.


Next I will ask whether your plan for a new version includes using the new 3.12.6 kernel which just appeared. I'm asking because in this kernel Kaolo and Popcornmix were so kind as to include the new I2S/PCM option on my request.https://github.com/raspberrypi/linux/pull/461

If you are close to release a new version build on this I will wait for it.
However, if you won't be using the new kernel or your release schedule lays further ahead, then I will try to build a new piCore based on the 3.12.6 kernel.

If you build on the new kernel, will you consider to activate the new options, and include the corresponding modules - should probably go in the ALSA package?

http://www.crazy-audio.com/projects/hifiberry-mini/hifiberry-mini-linux-configuration/

Code: [Select]

Enable the DMA module and the SOC codec driver
ARCH=arm CROSS_COMPILE=${CCPREFIX} make oldconfig
ARCH=arm CROSS_COMPILE=${CCPREFIX} make menuconfig
Device drivers –> Sound card support –> Advanced Linux Sound Architecture –> Alsa for SOC audio support –> Enable PCM5102 driver (or “build all ASoC CODEC drivers”)
Device drivers –> DMA engine support –> BCM2708 DMA Engine support

The reason that this new option is interesting is that it allows an audio DAC to be directly connected to the raspberry pi without the use of a USB connection. And there are now emerging several small and cheap high performance I2S-DACs:
http://www.crazy-audio.com/
http://www.tjaekel.com/T-DAC/raspi.html
http://www.element14.com/community/community/raspberry-pi/raspberry-pi-accessories/wolfson_pi


Regards
Steen

[bmarkus]

Hu Steen

thanks for the best wishes and Merry Christmas to you as well. Also thanks a lot for helping piCore become better and also make it better known through you player!

Current schedule is to release 5.1 on Week 2, 2014. Current 3.12.1 kernel is stabel. I tried few of the later kernels but they were buggy. I will make 3.12.6 kernel and rc4 however as thes RPi specific features look interesting and as a backup plan keep 3.12.1/rc3

As usual, I need you help in testing specially this DAC part.

Regards... Bela

[sbp]

Hi

Off course I will help testing any new build you produce - if you feel it is better that we continue testing these RC4 and RC5 builds in private - just send me a link in PM.

Regards
Steen

[bmarkus]

Just building new kernel and will see how it works in general. If OK, will make it available.

[bmarkus]

I built a new kernel with the same config as current 3.12.1 has. Strange, BusyBox depmod segfaults with 3.12.6 while it works fine with 3.12.1 No idea why. kmod is OK, but it breaks piCore (and TC in general) at few points like usage of /usr/local/lib for kernel modules and BusyBox depmod is hardwired to TC scripts, so not a drop-in replacement. Anyhow, I will make kernel with new features enabled.

[lykkedk]

Hey...

Marry X-mas!

Do you guys use a crosscompiler for compiling kernels ? - EG. the Linaro ?

// Jesper.

[bmarkus]

Hey...

Marry X-mas!

Do you guys use a crosscompiler for compiling kernels ? - EG. the Linaro ?

// Jesper.

Thanks, Merry XMAS to you!

Kernel is crosscompiled with gcc-4.7.3 from x-tools, not Linaro.

[lykkedk]

Okay thank you.

Can you quick -in very short, tell me, howto setup the needed enviroment for compiling kernels ?

I am having problems understanding how this works.

Past in time, i did a lot of kernel -compiling on my linuxbox, but that was not cross-compiling.
What i learned back then was to ::

Download the linux"vanilla" src. into /usr/src/linux and then softlink ln -s linux-xxx-vanillaxxx  /usr/src/linux
Then make menuconfig, make bzimage, make modules, and make modules install if needed (remember modules is only another word for firmware/driver)

Also i learned that when building a kernel, the only difference between building, and modules, was that the modules could be loaded only when needed, leaving a smaller kernel. BUT things like lirc_rpi, i2c eg... need to be build in for working proberly, and that is why i need to learn this for my raspberry.

// Jesper

[bmarkus]

Read this:

http://elinux.org/RPi_Kernel_Compilation

[sbp]

Hi Jesper

Here you can follow my progress, and there are a lot of good info from several experts also. I just recently started doing anything with linux, I think one year ago I haven't touched a linux computer:

However, this thread is about building the kernel: http://forum.tinycorelinux.net/index.php/topic,14964.0.html

Here is detailed info on making the modules. http://forum.tinycorelinux.net/index.php/topic,14634.30.html

Hope you figure it out otherwise please ask again.

Steen

[sbp]

Hi bmarkus

I managed to make a booting 3.12.6 piCore, based on the config file from your 3.12.1 (just adding the new I2S/PCM options).

It is "fat" as I simply took all the modules and included them in the piCore.gz file. Also I copied the two files "modules.builtin" and "modules.dep"

What do you think the next step is, should I start to only include the modules that are present in the previous 3.12.1 - to slim the new version - and take out the sound and net modules for ALSA and NET packages?

You mention busybox problems -  how do I know if I have that problem as well?

Steen

[lykkedk]

Hey Steen.

Can you help me, telling me, how you setup youre enviroment ?

Just did a new fresh Ubuntu 12.04 install here on my linuxbox.

// Jesper

[sbp]

Hi Jesper

As far as I remember I downloaded the cross-compiler https://github.com/raspberrypi/tools/tree/master/arm-bcm2708/arm-bcm2708hardfp-linux-gnueabi as described here: http://elinux.org/RPi_Kernel_Compilation

Then in the .config file I added:

Code: [Select]

CONFIG_CROSS_COMPILE="/cross/tools-master/arm-bcm2708/arm-bcm2708hardfp-linux-gnueabi/bin/arm-bcm2708hardfp-linux-gnueabi-"
And then just continue as you use to do it

Steen

[tinypoodle]

Past in time, i did a lot of kernel -compiling on my linuxbox, but that was not cross-compiling.
What i learned back then was to ::

Download the linux"vanilla" src. into /usr/src/linux and then softlink ln -s linux-xxx-vanillaxxx  /usr/src/linux

Above sounds very wrong.

http://linuxmafia.com/faq/Kernel/usr-src-linux-symlink.html

[lykkedk]

  okay okay ... the other way around then ::

# cd /usr/src
# ln -sfn linux-2.6.9-gentoo-r2 linux

// Jesper