$ nano 1_mk_rpi5_j16.sh
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#!/bin/bash
KERNEL=kernel_2712
make clean
make ARCH=arm64 CROSS_COMPILE=aarch64-linux-gnu- bcm2712_defconfig
time make -j16 ARCH=arm64 CROSS_COMPILE=aarch64-linux-gnu- Image modules dtbs
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$ nano 2_mk_rpi5_install_sdb.sh
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KERNEL=kernel_2712
sudo mount /dev/sdb1 mnt/boot
sudo mount /dev/sdb2 mnt/root
sudo env PATH=$PATH make -j16 ARCH=arm64 CROSS_COMPILE=aarch64-linux-gnu- INSTALL_MOD_PATH=mnt/root modules_install
sudo cp mnt/boot/$KERNEL.img mnt/boot/$KERNEL-backup.img
sudo cp arch/arm64/boot/Image mnt/boot/$KERNEL.img
sudo cp arch/arm64/boot/dts/broadcom/*.dtb mnt/boot/
sudo cp arch/arm64/boot/dts/overlays/*.dtb* mnt/boot/overlays/
sudo cp arch/arm64/boot/dts/overlays/README mnt/boot/overlays/
sudo umount mnt/boot
sudo umount mnt/root
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installの1行が抜けてたので追記しました。


$ chmod +x *.sh

$ ./1_mk_rpi5_j16.sh 
CPU:ryzen 3700x RAM:128GB
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real	8m38.307s
user	115m50.891s
sys	17m42.930s
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