ownery/linux

Mainline linux kernel for Armbian

Pre-built u-boot and kernels are available at https://xff.cz/kernels/

You may need some firmware files for some part of the functionality. Those are available at: https://megous.com/git/linux-firmware

If you want to reproduce my pre-built kernels exactly, you'll need to uncomment CONFIG_EXTRA_FIRMWARE_DIR and CONFIG_EXTRA_FIRMWARE in the defconfigs, and point CONFIG_EXTRA_FIRMWARE_DIR to a directory on your computer where the clone of https://megous.com/git/linux-firmware resides.

You can also leave those two config options commented out, and copy the contents of https://megous.com/git/linux-firmware to /lib/firmware/ on the target device.

Have fun!

Build instructions

These are rudimentary instructions and you need to understand what you're doing. These are just core steps required to build the ATF/u-boot/kernel. Downloading, verifying, renaming to correct directories is not described or mentioned. You should be able to infer missing necessary steps yourself for your particular needs.

Get necessary toolchains from:

• https://releases.linaro.org/components/toolchain/binaries/latest/aarch64-linux-gnu/

• https://releases.linaro.org/components/toolchain/binaries/latest/arm-linux-gnueabihf/

Extract toolchains and prepare the environment:

CWD=`pwd`
OUT=$CWD/builds
SRC=$CWD/u-boot
export PATH="$PATH:$CWD/Toolchains/arm/bin:$CWD/Toolchains/aarch64/bin"

Get and build ATF from https://github.com/ARM-software/arm-trusted-firmware:

make -C "$CWD/arm-trusted-firmware" PLAT=sun50i_a64 DEBUG=1 bl31
cp "$CWD/arm-trusted-firmware/build/sun50i_a64/debug/bl31.bin" "$KBUILD_OUTPUT"

Build u-boot from https://megous.com/git/u-boot/ (opi-v2020.04 branch) with appropriate defconfig.

My u-boot branch already has all the necessary patches integrated and is configured for quick u-boot/kernel startup.

make -C u-boot $BOARD_defconfig
make -C u-boot -j5

cp $KBUILD_OUTPUT/.config $OUT/pc2/uboot.config
cat $KBUILD_OUTPUT/{spl/sunxi-spl.bin,u-boot.itb} > $OUT/pc2/uboot.bin

Build the kernel for 64-bit boards:

export ARCH=arm64
export CROSS_COMPILE=aarch64-linux-gnu-
export KBUILD_OUTPUT=$OUT/.tmp/linux-arm64
mkdir -p $KBUILD_OUTPUT $OUT/pc2

make -C linux $BOARD_defconfig
make -C linux -j5 clean
make -C linux -j5 Image dtbs

cp -f $KBUILD_OUTPUT/arch/arm64/boot/Image $OUT/pc2/
cp -f $KBUILD_OUTPUT/.config $OUT/pc2/linux.config
cp -f $KBUILD_OUTPUT/arch/arm64/boot/dts/allwinner/sun50i-$BOARD.dtb $OUT/pc2/board.dtb

Build the kernel for 32-bit boards:

export ARCH=arm
export CROSS_COMPILE=arm-linux-gnueabihf-
export KBUILD_OUTPUT=$OUT/.tmp/linux-arm
mkdir -p $KBUILD_OUTPUT $OUT/pc

make $BOARD_defconfig
make -C linux $BOARD_defconfig
make -C linux -j5 clean
make -C linux -j5 zImage dtbs

cp -f $KBUILD_OUTPUT/arch/arm/boot/zImage $OUT/pc/
cp -f $KBUILD_OUTPUT/.config $OUT/pc/linux.config
cp -f $KBUILD_OUTPUT/arch/arm/boot/dts/sun8i-$BOARD.dtb $OUT/pc/board.dtb

Kernel lockup issues

If you're getting lockups on boot or later during thermal regulation, you're missing an u-boot patch.

This patch is necessary to run this kernel!

These lockups are caused by improper NKMP clock factors selection in u-boot for PLL_CPUX. (M divider should not be used. P divider should be used only for frequencies below 240MHz.)

This patch for u-boot fixes it:

0001-sunxi-h3-Fix-PLL1-setup-to-never-use-dividers.patch

Kernel side is already fixed in this kernel tree.