User:Mai
Contents
1 Status for Samsung Chromebook Plus v1 aka kevin aka gru-kevin aka xe513c24
1.1 Kernel
linux-libre-64 (armv7h) works but needs to be packed correctly to boot, the following is a rough guide on how i was able to boot this kernel on this hardware
1.2 what does not work
- onboard wifi - probably more stuff
1.3 What you will need
- this laptop :P - micro sd card at least 2GB, 8+GB reccomended - another computer that has a linux environment so we can download / extract / pack the kernel and install rootfs
2 Unlock external booting
2.1 Switch to developer mode
- Turn off the laptop.
- To invoke Recovery mode, you hold down the ESC and Refresh keys and poke the Power button.
- At the Recovery screen press Ctrl-D (there’s no prompt - you have to know to do it).
- Confirm switching to developer mode by pressing enter, and the laptop will reboot and reset the system. This takes about 10-15 minutes.
Note: After enabling developer mode, you will need to press Ctrl-D each time you boot, or wait 30 seconds to continue booting.
2.2 Enable booting from external storage
- After booting into developer mode, hold Ctrl and Alt and poke the F2 key. This will open up the developer console.
- Type root to the login screen.
- Then type this to enable USB booting:
# crossystem dev_boot_usb=1 # crossystem dev_default_boot=usb
Reboot the system to allow the change to take effect.
Source: https://chromebooks.readthedocs.io/en/latest/source/README.html#switch-to-developer-mode
3 Install packages
pacman -S vboot-utils uboot-tools gptfdisk dtc
4 Gather files
$ mkdir parabola-armv7-64 $ cd parabola-armv7-64 $ wget -c https://redirector.parabola.nu/iso/armv7h-systemd-cli-2020.02/parabola-armv7h-systemd-cli-2020.02-tarball.tar.gz $ wget -c https://redirector.parabola.nu/iso/armv7h-systemd-cli-2020.02/parabola-armv7h-systemd-cli-2020.02-tarball.tar.gz.sig $ wget -c https://repomirror.parabola.nu/pool/parabola/linux-libre-64-5.11.11-3-armv7h.pkg.tar.xz $ wget -c https://repomirror.parabola.nu/pool/parabola/linux-libre-64-5.11.11-3-armv7h.pkg.tar.xz.sig $ wget -c https://git.parabola.nu/abslibre.git/plain/libre/linux-libre/kernel.keyblock $ wget -c https://git.parabola.nu/abslibre.git/plain/libre/linux-libre/kernel_data_key.vbprivk $ gpg --recv-keys FBCC5AD7421197B7ABA72853908710913E8C7778 $ gpg --verify parabola-armv7h-systemd-cli-2020.02-tarball.tar.gz.sig $ gpg --recv-keys 782F9DDBE36BA7F3D4DE49065F5DFCC14177E263 $ gpg --verify linux-libre-64-5.11.11-3-armv7h.pkg.tar.xz.sig
save the following code as partition_vboot.sh
#!/bin/bash
DISK="$1"
# Make sure only root can run our script
if [ "$(id -u)" != "0" ]; then
echo "This script must be run as root" 1>&2
exit 1
fi
if [ x"$DISK" == 'x' ]; then
echo "This script requires a base block device as its only arguement" 1>&2
echo "example: $0 /dev/sdb"
exit 1
fi
DISK_DEVICE_NAME="$(echo $DISK | awk -F'/' '{print $NF}')"
if [[ "$DISK_DEVICE_NAME" == *mmcblk* ]]; then
ROOT_PARTITION="$DISK"p2
SWAP_PARTITION="$DISK"p3
else
ROOT_PARTITION="$DISK"2
SWAP_PARTITION="$DISK"3
fi
# TODO allow specify TOTAL_SECTORS
TOTAL_SECTORS=$(cat /sys/block/$DISK_DEVICE_NAME/size)
SECTOR_SIZE=$(cat /sys/block/$DISK_DEVICE_NAME/queue/hw_sector_size)
# the following are in sectors, 1MB = 2048 sectors
FIRST_GAP_SIZE=8192 # 2048 sectors * 4MB
LAST_GAP_SIZE=2048 # 2048 sectors * 1MB
SWAP_PART_SIZE=8388608 # 2048 sectors * 4096MB
KERNEL_PART_SIZE=65536 # 2048 sectors * 32MB
# layout arithmatic
FIRST_GAP_START=0
FIRST_GAP_END=$(( $FIRST_GAP_SIZE - 1 ))
KERNEL_PART_START=$(( $FIRST_GAP_END + 1 ))
KERNEL_PART_END=$(( $FIRST_GAP_END + $KERNEL_PART_SIZE ))
ROOTFS_PART_START=$(( $KERNEL_PART_END + 1 ))
LAST_GAP_END=$(( $TOTAL_SECTORS - 1 ))
LAST_GAP_START=$(( $LAST_GAP_END - $LAST_GAP_SIZE + 1 ))
if [ $TOTAL_SECTORS -lt 10000000 ]; then # if size of disk is less than 5GB do not make swap
MAKESWAP='false'
ROOTFS_PART_END=$(( $LAST_GAP_START - 1 ))
SWAP_PART_END=0
SWAP_PART_START=0
else
MAKESWAP='true'
SWAP_PART_END=$(( $LAST_GAP_START - 1 ))
SWAP_PART_START=$(( $SWAP_PART_END - $SWAP_PART_SIZE + 1 ))
ROOTFS_PART_END=$(( $SWAP_PART_START - 1 ))
fi
echo "TOTAL_SECTORS = $TOTAL_SECTORS"
echo "SECTOR_SIZE = $SECTOR_SIZE"
echo ""
echo "FIRST_GAP_SIZE = $FIRST_GAP_SIZE"
echo "LAST_GAP_SIZE = $LAST_GAP_SIZE"
echo "SWAP_PART_SIZE = $SWAP_PART_SIZE"
echo "KERNEL_PART_SIZE = $KERNEL_PART_SIZE"
echo ""
echo "FIRST_GAP_START = $FIRST_GAP_START $(( $FIRST_GAP_START / 2048 )) MB"
echo "FIRST_GAP_END = $FIRST_GAP_END"
echo "KERNEL_PART_START = $KERNEL_PART_START $(( $KERNEL_PART_START / 2048 )) MB"
echo "KERNEL_PART_END = $KERNEL_PART_END"
echo "ROOTFS_PART_START = $ROOTFS_PART_START $(( $ROOTFS_PART_START / 2048 )) MB"
echo "ROOTFS_PART_END = $ROOTFS_PART_END"
echo "SWAP_PART_START = $SWAP_PART_START $(( $SWAP_PART_START / 2048 )) MB"
echo "SWAP_PART_END = $SWAP_PART_END"
echo "LAST_GAP_START = $LAST_GAP_START $(( $LAST_GAP_START / 2048 )) MB"
echo "LAST_GAP_END = $LAST_GAP_END"
# use `sgdisk --list-types' to get all possible type codes
KERNEL_PART_TYPE='7f00'
ROOTFS_PART_TYPE='7f01'
SWAP_PART_TYPE='8200'
# wipe disk, and create new gpt partition table
sgdisk --zap-all $DISK
sgdisk -o $DISK
# create the kernel partition
sgdisk --new=1:$KERNEL_PART_START:$KERNEL_PART_END $DISK
sgdisk --typecode=1:$KERNEL_PART_TYPE $DISK
sgdisk --change-name=1:Kernel $DISK
sgdisk --attributes=1:=:015A000000000000 $DISK
# create the rootfs partition
sgdisk --new=2:$ROOTFS_PART_START:$ROOTFS_PART_END $DISK
sgdisk --typecode=2:$ROOTFS_PART_TYPE $DISK
sgdisk --change-name=2:Root $DISK
mkfs.ext4 $ROOT_PARTITION
# create the swap partition
if [ $MAKESWAP = 'true' ]; then
sgdisk --new=3:$SWAP_PART_START:$SWAP_PART_END $DISK
sgdisk --typecode=3:$SWAP_PART_TYPE $DISK
sgdisk --change-name=3:Swap $DISK
mkswap $SWAP_PARTITION
fi
sgdisk --print $DISK
lsblk $DISK
5 partition micro sd card & mount the rootfs partition
partition_vboot.sh is a replacement for cgpt i made that uses sgdisk to create a compatible partition layout for depthcharge chromebooks (asus c201 & samsung chromebook plus v1). I have tested it with cards as small as 2GB, it will automatically make a 4GB swap partition if the size of the disk is detected to be above 4GB, the rest of the disk will be used for the rootfs partition
# sh partition_vboot.sh /dev/sdX
if you dont want to run this script you can follow the partitioning instructions on the archlinuxarm wiki page for this device https://archlinuxarm.org/platforms/armv8/rockchip/samsung-chromebook-plus
after the rootfs partition is created and formated, mount it
# mkdir $MOUNTPOINT # mount /dev/sdX2 $MOUNTPOINT
6 extract / copy files
# bsdtar -xf parabola-armv7h-systemd-cli-2020.02-tarball.tar.gz -C $MOUNTPOINT # bsdtar -xf linux-libre-64-5.11.11-3-armv7h.pkg.tar.xz -C $MOUNTPOINT # cp linux-libre-64-5.11.11-3-armv7h.pkg.tar.xz $MOUNTPOINT/var/cache/pacman/pkg/ # echo > $MOUNTPOINT/etc/fstab # mkdir $MOUNTPOINT/boot/pack # cp kernel.keyblock $MOUNTPOINT/boot/pack # cp kernel_data_key.vbprivk $MOUNTPOINT/boot/pack # cp $MOUNTPOINT/usr/lib/modules/5.11.11-gnu-3-64-ARCH/vmlinuz $MOUNTPOINT/boot/pack # cp $MOUNTPOINT/boot/dtbs/linux-libre-64/rockchip/rk3399-gru-kevin.dtb $MOUNTPOINT/boot/pack # cd $MOUNTPOINT/boot/pack # lz4 -k vmlinuz # echo "console=tty0 console=ttyS2,115200n8 earlyprintk=ttyS2,115200n8 init=/sbin/init root=PARTUUID=%U/PARTNROFF=1 rootwait rw noinitrd" > cmdline # dd if=/dev/zero of=bootloader.bin bs=512 count=1
paste the following code into kernel.its
/dts-v1/;
/ {
description = "Chrome OS kernel image with one or more FDT blobs";
images {
kernel@1{
description = "kernel";
data = /incbin/("vmlinuz.lz4");
type = "kernel_noload";
arch = "arm64";
os = "linux";
compression = "lz4";
load = <0>;
entry = <0>;
};
fdt@1{
description = "rk3399-gru-kevin.dtb";
data = /incbin/("rk3399-gru-kevin.dtb");
type = "flat_dt";
arch = "arm64";
compression = "none";
hash@1{
algo = "sha1";
};
};
};
configurations {
default = "conf@1";
conf@1{
kernel = "kernel@1";
fdt = "fdt@1";
};
};
};
# mkimage -f kernel.its kernel.itb
if you see the following error message, just ignore, it will still work
kernel.its:6.17-15.11: Warning (unit_address_vs_reg): /images/kernel@1: node has a unit name, but no reg or ranges property kernel.its:16.14-25.11: Warning (unit_address_vs_reg): /images/fdt@1: node has a unit name, but no reg or ranges property kernel.its:22.19-24.15: Warning (unit_address_vs_reg): /images/fdt@1/hash@1: node has a unit name, but no reg or ranges property kernel.its:29.15-32.11: Warning (unit_address_vs_reg): /configurations/conf@1: node has a unit name, but no reg or ranges property mkimage: verify_header failed for FIT Image support with exit code 1
and paste the following code into pack_vboot.sh
futility --debug vbutil_kernel \
--pack vmlinux.kpart \
--version 1 \
--vmlinuz kernel.itb \
--arch aarch64 \
--keyblock kernel.keyblock \
--signprivate kernel_data_key.vbprivk \
--config cmdline \
--bootloader bootloader.bin
Now run the following commands:
# sh pack_vboot.sh # dd if=vmlinux.kpart of=/dev/sdX1 # cd # umount $MOUNTPOINT
7 Boot!
it should boot up. (press ctrl+u at the white bios screen if it still boots into chromeos)
login as root
in order to update the system you will need some way to connect to the internet, i am using a usb-c ethernet adapter https://www.amazon.com/Nekteck-Ethernet-Compatible-Pixelbook-Thunderbolt/dp/B0749DCDRV/
plug in the usb ethernet and dhcp should assign an ip
then sync the time
# systemctl restart systemd-timesyncd.service # pacman -Sy # pacman -S archlinux-keyring archlinux32-keyring archlinuxarm-keyring parabola-keyring
it will fail because of keyring, but you downloaded it!
# pacman -U /var/cache/pacman/pkg/*-keyring-* # pacman -S archlinux-keyring archlinux32-keyring archlinuxarm-keyring parabola-keyring # pacman -S archlinux-keyring archlinux32-keyring archlinuxarm-keyring parabola-keyring
TODO: get pacman-key --refresh to work. try: https://wiki.parabola.nu/Parabola_Keyring
as an alternative temporary way around, we will just disable signature checking for this test environment.
sed -i '/^SigLevel.*/SigLevel = Never/' /etc/pacman.conf
# pacman -S linux-libre-64 --overwrite '/*' # pacman -Su linux-libre-firmware acpi vim nano networkmanager
8 Bonus extra info
8.1 make your own debug port breakout
I dont know where to get a servo board but the you can make your own debug header breakout to get serial console access / early boot logs etc
the breakout https://www.amazon.com/Proto-Advantage-DR040D254P050-50-Pin-Connector-Adapter/dp/B097S2268V or https://www.ebay.com/itm/202502988342
the connector https://www.digikey.com/en/products/detail/panasonic-electric-works/AXK850145WG/1986616
usb <--> rs232 https://www.amazon.com/HiLetgo-CP2102-Converter-Adapter-Downloader/dp/B00LODGRV8 (get 2)
servo connector pinout is described in this pdf (page 14) (V2 DEBUG HEADER)
https://www.chromium.org/chromium-os/servo/810-10010-03_20120227_servo_SCH_0.pdf
you can use a continuity meter to determine connector orientation by finding the corner pin that is ground
PIN-33 UART1_DUT_SERVO_TX --+ +-- PIN-17 UART2_DUT_SERVO_TX
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49 vG vG G 1
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9753197531975319753197531
1234567890123210987654321
0864208642086420864208642
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50 G G ^ G ^ G 2
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PIN-32 UART1_SERVO_DUT_TX --+ +-- PIN-16 UART2_SERVO_DUT_TX
GND PINS = 1, 8, 15, 20, 31, 36, 42
8.2 set bios boot timeout to 2 seconds
https://old.reddit.com/r/Crouton/comments/2szn59/how_to_shorten_os_verfication_warning_screen_on/
https://old.reddit.com/r/chromeos/comments/6j5ig9/chromebook_pro_hardware_writeprotect/dll73kq/
install package from aur flashrom-chromeos
info about gbb flags
/* Flags for .flags field */ /* Reduce the dev screen delay to 2 sec from 30 sec to speedup factory. */ #define GBB_FLAG_DEV_SCREEN_SHORT_DELAY 0x00000001 /* * BIOS should load option ROMs from arbitrary PCI devices. We'll never enable * this ourselves because it executes non-verified code, but if a customer * wants to void their warranty and set this flag in the read-only flash, they * should be able to do so. */ #define GBB_FLAG_LOAD_OPTION_ROMS 0x00000002 /* * The factory flow may need the BIOS to boot a non-ChromeOS kernel if the * dev-switch is on. This flag allows that. */ #define GBB_FLAG_ENABLE_ALTERNATE_OS 0x00000004 /* Force dev switch on, regardless of physical/keyboard dev switch position. */ #define GBB_FLAG_FORCE_DEV_SWITCH_ON 0x00000008 /* Allow booting from USB in dev mode even if dev_boot_usb=0. */ #define GBB_FLAG_FORCE_DEV_BOOT_USB 0x00000010 /* Disable firmware rollback protection. */ #define GBB_FLAG_DISABLE_FW_ROLLBACK_CHECK 0x00000020 /* Allow Enter key to trigger dev->tonorm screen transition */ #define GBB_FLAG_ENTER_TRIGGERS_TONORM 0x00000040 /* Allow booting Legacy OSes in dev mode even if dev_boot_legacy=0. */ #define GBB_FLAG_FORCE_DEV_BOOT_LEGACY 0x00000080 /* Allow booting using alternate keys for FAFT servo testing */ #define GBB_FLAG_FAFT_KEY_OVERIDE 0x00000100 /* Disable EC software sync */ #define GBB_FLAG_DISABLE_EC_SOFTWARE_SYNC 0x00000200 /* Default to booting legacy OS when dev screen times out */ #define GBB_FLAG_DEFAULT_DEV_BOOT_LEGACY 0x00000400 /* Disable PD software sync */ #define GBB_FLAG_DISABLE_PD_SOFTWARE_SYNC 0x00000800 /* Disable shutdown on lid closed */ #define GBB_FLAG_DISABLE_LID_SHUTDOWN 0x00001000 /* * Allow full fastboot capability in firmware even if * dev_boot_fastboot_full_cap=0. */ #define GBB_FLAG_FORCE_DEV_BOOT_FASTBOOT_FULL_CAP 0x00002000 /* Enable serial console */ #define GBB_FLAG_ENABLE_SERIAL 0x00004000 source: https://chromium.googlesource.com/chromiumos/platform/vboot/+/master/_vboot_reference/firmware/include/gbb_header.h
