diff options
Diffstat (limited to 'kernel.md')
| -rw-r--r-- | kernel.md | 13 |
1 files changed, 7 insertions, 6 deletions
@@ -114,8 +114,8 @@ cross compile the kernel and get all of this to run on the Raspberry Pi. Unless you have used the `download.sh` script from [the cross toolchain](crosscc.md), you will need to download and unpack the following: -* [BusyBox](https://busybox.net/downloads/busybox-1.31.1.tar.bz2) -* [Linux](https://github.com/raspberrypi/linux/archive/raspberrypi-kernel_1.20190925-1.tar.gz) +* [BusyBox](https://busybox.net/downloads/busybox-1.32.0.tar.bz2) +* [Linux](https://github.com/raspberrypi/linux/archive/raspberrypi-kernel_1.20201201-1.tar.gz) You should still have the following environment variables set from building the cross toolchain: @@ -163,7 +163,7 @@ Alternatively you can start from scratch by creating a default configuration: To compile BusyBox, we'll first do the usual setup for the out-of-tree build: - srcdir="$BUILDROOT/src/busybox-1.31.1" + srcdir="$BUILDROOT/src/busybox-1.32.0" export KBUILD_OUTPUT="$BUILDROOT/build/bbstatic" mkdir -p "$KBUILD_OUTPUT" @@ -200,7 +200,7 @@ to the sysroot directory as `bbstatic`. First, we do the same dance again for the kernel out of tree build: - srcdir="$BUILDROOT/src/linux-raspberrypi-kernel_1.20190925-1" + srcdir="$BUILDROOT/src/linux-raspberrypi-kernel_1.20201201-1" export KBUILD_OUTPUT="$BUILDROOT/build/linux" mkdir -p "$KBUILD_OUTPUT" @@ -227,7 +227,7 @@ generally don't contain **CONFIG_**. Same as with BusyBox, we insert the cross compile prefix into the configuration file: - sed -i "$PKGBUILDDIR/.config" -e 's,^CONFIG_CROSS_COMPILE=.*,CONFIG_CROSS_COMPILE="'$TARGET'-",' + sed -i "$KBUILD_OUTPUT/.config" -e 's,^CONFIG_CROSS_COMPILE=.*,CONFIG_CROSS_COMPILE="'$TARGET'-",' And then finally build the kernel: @@ -278,7 +278,7 @@ some pitfalls here: So instead of the `cpio` tool, we are going to use a tool from the Linux kernel tree called `gen_init_cpio`: - gcc "$BUILDROOT/src/linux-raspberrypi-kernel_1.20190925-1/usr/gen_init_cpio.c" -o gen_init_cpio + gcc "$BUILDROOT/src/linux-raspberrypi-kernel_1.20201201-1/usr/gen_init_cpio.c" -o gen_init_cpio This tool allows us to create a cpio image from a very simple file listing and produces exactely the format that the kernel understands. @@ -363,6 +363,7 @@ ramdisk: ./gen_init_cpio initrd.files | xz --check=crc32 > initrd.xz cp initrd.xz "$SYSROOT/boot" + cd "$BUILDROOT" The option `--check=crc32` forces the `xz` utility to create CRC-32 checksums instead of using sha256. This is necessary, because the kernel built in |