U-boot cmdline: Difference between revisions
From embeddedTS Manuals
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The Linux kernel cmdline can be customized by modifying the cmdline_append variable. | The Linux kernel cmdline can be customized by modifying the cmdline_append variable. The variable contents are clobbered when set, so be sure to specify the full desired cmdline string. | ||
<source lang=bash> | <source lang=bash> | ||
env set cmdline_append console=ttymxc0,115200 init=/sbin/init | env set cmdline_append console=ttymxc0,115200 init=/sbin/init quiet | ||
env save | env save | ||
</source> | </source> | ||
The kernel command line can also be modified from from the on-board Linux. Debian (and other distributions) provide a U-Boot utilities package that contains the tools necessary to create a U-Boot script: | |||
<source lang=bash> | |||
apt-get update && apt-get install u-boot-tools -y | |||
echo "env set cmdline_append console=ttymxc0,115200 init=/sbin/init quiet" > /boot/boot.scr | |||
mkimage -A arm -T script -C none -n 'tsimx6 boot script' -d /boot/boot.scr /boot/boot.ub | |||
</source> | |||
The boot.scr includes the plain text commands to be run in U-Boot on startup. The mkimage tool adds a checksum and header to this file which can be loaded by U-Boot. The .ub file should not be edited directly. | |||
Latest revision as of 14:01, 27 September 2018
The Linux kernel cmdline can be customized by modifying the cmdline_append variable. The variable contents are clobbered when set, so be sure to specify the full desired cmdline string.
env set cmdline_append console=ttymxc0,115200 init=/sbin/init quiet
env save
The kernel command line can also be modified from from the on-board Linux. Debian (and other distributions) provide a U-Boot utilities package that contains the tools necessary to create a U-Boot script:
apt-get update && apt-get install u-boot-tools -y
echo "env set cmdline_append console=ttymxc0,115200 init=/sbin/init quiet" > /boot/boot.scr
mkimage -A arm -T script -C none -n 'tsimx6 boot script' -d /boot/boot.scr /boot/boot.ub
The boot.scr includes the plain text commands to be run in U-Boot on startup. The mkimage tool adds a checksum and header to this file which can be loaded by U-Boot. The .ub file should not be edited directly.