64-bit Mainline kernel on Raspberry Pi 3
I've struggled a little recently on running vanilla kernel on Raspberry Pi 3. Still I didn't completely understand the internals. Anyway sharing the steps may be useful for someone like me.
Download toolchain and rootfs from Linaro.
And clone following repos * Vanilla kernel * Raspberry Pi kernel - Checkout same version as vanilla kernel you are going to use * Raspberry pi firmware - Or download only the files under boot directory of this repo
I've created a directory structure as below. You can have similar one based on your convenience.
$ ls ~/Desktop/kernel/
total 44K
drwxr-xr-x 2 kaba kaba 4.0K Sep 23 20:04 downloads
drwxrwxr-x 2 kaba kaba 4.0K Oct 4 10:22 firmware
drwxr-xr-x 22 kaba kaba 4.0K Oct 6 11:55 kernel_out
drwxr-xr-x 18 kaba kaba 4.0K Sep 12 2013 rootfs
drwxr-xr-x 26 kaba kaba 4.0K Oct 3 21:30 rpi_kernel
drwxr-xr-x 2 kaba kaba 4.0K Oct 7 12:13 rpi_out
drwxr-xr-x 3 kaba kaba 4.0K Sep 23 19:43 toolchain
drwxr-xr-x 26 kaba kaba 4.0K Oct 3 22:04 vanila_kernel
kaba@kaba-Vostro-1550:~/Desktop/kernel
$
Export PATH variable to include toolchain directory.
$ echo $PATH
/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin:/usr/games:/usr/local/games:/snap/bin:/home/kaba/Desktop/kernel/toolchain/gcc-linaro-7.3.1-2018.05-x86_64_aarch64-linux-gnu/bin/
kaba@kaba-Vostro-1550:~/Desktop/kernel/vanila_kernel
$
Configure and build 64-bit Vanilla kernel.
kaba@kaba-Vostro-1550:~/Desktop/kernel/vanila_kernel
$ make O=../kernel_out ARCH=arm64 CROSS_COMPILE=aarch64-linux-gnu- defconfig
.
.
.
kaba@kaba-Vostro-1550:~/Desktop/kernel/vanila_kernel
$ make -j4 O=../kernel_out ARCH=arm64 CROSS_COMPILE=aarch64-linux-gnu-
-j according to your machine. And wait for the build to complete.
Now build device-tree in Raspberry Pi kernel repo.
kaba@kaba-Vostro-1550:~/Desktop/kernel/rpi_kernel
$ make O=../rpi_out ARCH=arm64 CROSS_COMPILE=aarch64-linux-gnu- defconfig
make[1]: Entering directory '/home/kaba/Desktop/kernel/rpi_out'
HOSTCC scripts/basic/fixdep
GEN ./Makefile
HOSTCC scripts/kconfig/conf.o
YACC scripts/kconfig/zconf.tab.c
LEX scripts/kconfig/zconf.lex.c
HOSTCC scripts/kconfig/zconf.tab.o
HOSTLD scripts/kconfig/conf
*** Default configuration is based on 'defconfig'
#
# configuration written to .config
#
make[1]: Leaving directory '/home/kaba/Desktop/kernel/rpi_out'
kaba@kaba-Vostro-1550:~/Desktop/kernel/rpi_kernel
$ make O=../rpi_out ARCH=arm64 CROSS_COMPILE=aarch64-linux-gnu- dtbs
.
.
.
Partition your memory card into two. The first one should be FAT32 and second one should be EXT4. The first partition should be a boot partition.
balakumaran@balakumaran-USB:~/Desktop/RPi/linux_build$ sudo parted /dev/sdd
[sudo] password for balakumaran:
GNU Parted 3.2
Using /dev/sdd
Welcome to GNU Parted! Type 'help' to view a list of commands.
(parted) print
Model: MXT-USB Storage Device (scsi)
Disk /dev/sdd: 31.9GB
Sector size (logical/physical): 512B/512B
Partition Table: msdos
Disk Flags:
Number Start End Size Type File system Flags
1 1049kB 106MB 105MB primary fat32 boot, lba
2 106MB 31.9GB 31.8GB primary
(parted) help rm
rm NUMBER delete partition NUMBER
NUMBER is the partition number used by Linux. On MS-DOS disk labels, the primary partitions number from 1 to 4, logical partitions from 5 onwards.
(parted) rm 1
(parted) rm 2
(parted) print
Model: MXT-USB Storage Device (scsi)
Disk /dev/sdd: 31.9GB
Sector size (logical/physical): 512B/512B
Partition Table: msdos
Disk Flags:
Number Start End Size Type File system Flags
(parted) help mkpart
mkpart PART-TYPE [FS-TYPE] START END make a partition
PART-TYPE is one of: primary, logical, extended
FS-TYPE is one of: zfs, btrfs, nilfs2, ext4, ext3, ext2, fat32, fat16, hfsx, hfs+, hfs, jfs, swsusp, linux-swap(v1), linux-swap(v0), ntfs, reiserfs, freebsd-ufs, hp-ufs, sun-ufs,
xfs, apfs2, apfs1, asfs, amufs5, amufs4, amufs3, amufs2, amufs1, amufs0, amufs, affs7, affs6, affs5, affs4, affs3, affs2, affs1, affs0, linux-swap, linux-swap(new), linux-swap(old)
START and END are disk locations, such as 4GB or 10%. Negative values count from the end of the disk. For example, -1s specifies exactly the last sector.
'mkpart' makes a partition without creating a new file system on the partition. FS-TYPE may be specified to set an appropriate partition ID.
(parted) mkpart primary fat32 2048s 206848s
(parted) mkpart primary ext4 208896s -1s
(parted) print
Model: MXT-USB Storage Device (scsi)
Disk /dev/sdd: 31.9GB
Sector size (logical/physical): 512B/512B
Partition Table: msdos
Disk Flags:
Number Start End Size Type File system Flags
1 1049kB 106MB 105MB primary fat32 lba
2 107MB 31.9GB 31.8GB primary ext4 lba
(parted) set 1 boot on
(parted) print
Model: MXT-USB Storage Device (scsi)
Disk /dev/sdd: 31.9GB
Sector size (logical/physical): 512B/512B
Partition Table: msdos
Disk Flags:
Number Start End Size Type File system Flags
1 1049kB 106MB 105MB primary fat32 boot, lba
2 107MB 31.9GB 31.8GB primary ext4 lba
(parted) quit
Information: You may need to update /etc/fstab.
balakumaran@balakumaran-USB:~/Desktop/RPi/linux_build$ sudo fdisk -l /dev/sdd
Disk /dev/sdd: 29.7 GiB, 31914983424 bytes, 62333952 sectors
Units: sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disklabel type: dos
Disk identifier: 0xcde890ba
Device Boot Start End Sectors Size Id Type
/dev/sdd1 * 2048 206848 204801 100M c W95 FAT32 (LBA)
/dev/sdd2 208896 62333951 62125056 29.6G 83 Linux
balakumaran@balakumaran-USB:~/Desktop/RPi/linux_build$
Copy firmware and kernel to boot partition.
kaba@kaba-Vostro-1550:~/Desktop/kernel/vanila_kernel
$ sudo mount /dev/sdb1 /mnt/boot/
kaba@kaba-Vostro-1550:~/Desktop/kernel/vanila_kernel
$ sudo cp ../kernel_out/arch/arm64/boot/Image /mnt/boot/kernel8.img
[sudo] password for kaba:
kaba@kaba-Vostro-1550:~/Desktop/kernel/vanila_kernel
$ sudo cp ../firmware/* /mnt/boot/
kaba@kaba-Vostro-1550:~/Desktop/kernel/vanila_kernel
$
Install device-tree blobs from Raspberry Pi repo into boot partition. The device-tree in upstream kernel is not working for some reason. I couldn't get more information regarding that.
kaba@kaba-Vostro-1550:~/Desktop/kernel/rpi_kernel
$ make O=../rpi_out ARCH=arm64 CROSS_COMPILE=aarch64-linux-gnu- bcmrpi3_defconfig
kaba@kaba-Vostro-1550:~/Desktop/kernel/rpi_kernel
$ sudo make O=../rpi_out ARCH=arm64 CROSS_COMPILE=aarch64-linux-gnu- INSTALL_PATH=/mnt/boot/ dtbs_install
Copy rootfs into second partition. Also install kernel modules into that.
kaba@kaba-Vostro-1550:~/Desktop/kernel/vanila_kernel
$ sudo mount /dev/sdb2 /mnt/rootfs/
kaba@kaba-Vostro-1550:~/Desktop/kernel/vanila_kernel
$ sudo cp -rf ../rootfs/* /mnt/rootfs/
kaba@kaba-Vostro-1550:~/Desktop/kernel/vanila_kernel
$ sudo make O=../kernel_out ARCH=arm64 CROSS_COMPILE=aarch64-linux-gnu- INSTALL_MOD_PATH=/mnt/rootfs/ modules_install
kaba@kaba-Vostro-1550:~/Desktop/kernel/vanila_kernel
$ sync
Create config.txt and cmdline.txt as follows. Make sure you update device-tree and overlay_prefix based on your configuration.
kaba@kaba-Vostro-1550:/mnt/boot
$ cat cmdline.txt
dwc_otg.lpm_enable=0 console=serial0,115200 root=/dev/mmcblk0p2 rootfstype=ext4 rootwait
kaba@kaba-Vostro-1550:/mnt/boot
$ cat config.txt
dtoverlay=vc4-fkms-v3d,cma-256
disable_overscan=1
dtparam=audio=on
device_tree=dtbs/4.19.0-rc5-v8+/broadcom/bcm2710-rpi-3-b.dtb
overlay_prefix=dtbs/4.19.0-rc5-v8+/overlays/
enable_uart=1
kaba@kaba-Vostro-1550:/mnt/boot
$
Put the SD card in Raspberry Pi 3 and boot.