Tiny Core Base > Raspberry Pi
Build a new version based on raspberry kernel 4
sbp:
--- Quote from: curaga on July 19, 2015, 05:09:05 AM ---Please start from a known working config, trying to enable things one by one from the rpi default config will take you long.
--- End quote ---
Thanks. I agree and that is what I have been doing before.
Usually I extracted a .config from a piCore that Belá produced. However, I think the jump from 3.18.y to 4.0.y is too large for that to work.
At least this time I couldn't build a working version on 4.0 from a config from a 3.18 piCore.
I therefore think it would be a benefit for us all if we could define the piCore needed options so that they could be added to the config that is used for building the raspberry images from the Raspberry foundation.
The bcm2709_defconfig is used for that purpose (on a RPI2) and if we could figure out which options we need to add to this we would be able to benefit from the rapid development of the raspberry kernel in the piCore community as well.
Thus, For the moment I have these options added to the end of the bcm2709_defconfig file:
#START PICORE SPECIFIC SETTINGS:
CONFIG_CROSS_COMPILE="/cross/tools-master/arm-bcm2708/arm-bcm2708hardfp-linux-gnueabi/bin/arm-bcm2708hardfp-linux-gnueabi-"
CONFIG_LOCALVERSION="-piCore-v7"
CONFIG_BLK_DEV_INITRD=y
CONFIG_INITRAMFS_SOURCE=""
CONFIG_RD_GZIP=y
CONFIG_HAVE_KERNEL_LZMA=y
CONFIG_HAVE_KERNEL_XZ=y
CONFIG_HAVE_KERNEL_LZO=y
CONFIG_KERNEL_GZIP=y
CONFIG_ZSMALLOC=y
CONFIG_ZCACHE=y
CONFIG_ZRAM=y
CONFIG_BLK_DEV_LOOP_MIN_COUNT=8
CONFIG_BLK_DEV_RAM_COUNT=16
CONFIG_BLK_DEV_RAM_SIZE=4096
#STOP PICORE SPECIFIC SETTINGS:
Then I rename this file to .config , use "make ARCH=arm menuconfig" save the .config and start building the kernel and modules.
But obviously I still need to enable a few important options in the config file before a working version of piCore can be build. I don't think I'm missing much as all other things seems to work if only the loop devices could be mounted.
Steen
My proposal for defining piCore specific options in the config file is well in line with this proposal in the github https://github.com/raspberrypi/linux/issues/1065 and especially if you look at this post here where specific options for making a working Gentoo kernel is discussed: https://github.com/gtgt/gt-overlay/blob/master/patches/sys-kernel/pf-sources/3.11.1-4567_distro-Gentoo-Kconfig.patch
Paul_123:
Have you tried the 3.18 config, And run "make oldconfig"
bmarkus:
My experience is that after defconfig it requires lot of changes in config to get it working and trial and failure cycles, better to forget.
Using .config from a different main kernel version is also problematic, I had many head aches in the past.
The best way is to take a Raspbian kernel config as bases for the same kernel version and make changes on it. For sure it work and can be trusted for common stuff like SD card, USB, Ethernet, etc. What piCore (TC) need is the squashf fs module mandatory to mount TCZ's and optionally zram/zswap for compressed RAM blocks and compressed swap. Good point with Raspbian 4.0.8 is except zswap all necessary moduels enabled, you must enable only zswap to get it working on TC way.
There are smaller issues, that various new hw modules (RTC, USB devices, etc.) are not enabled in the Raspbian config, but it is easy to fix. Also, you may move some modules to the kernel, but all of these are not necessary to have it working.
sbp:
Thanks
So no easy path!
I'm a little confused about the development at raspberry, there seems to be a move from using spi-bcm2708 towards spi-bcm2835.
This has the consequence that different config files are used.
So what do you build piCore on the 2708 path or have you moved to 2835?
Regards
Steen
bmarkus:
--- Quote from: sbp on July 19, 2015, 02:07:32 PM ---
So no easy path!
--- End quote ---
Why? It is easy to rebuild kernel based on Raspbian, only one setting must be changed. After updating firmware from GITHUB it works. I have done it for armv6 and it was working at first.
There is only one more easier way, to use piCore's boot :)
Navigation
[0] Message Index
[#] Next page
[*] Previous page
Go to full version