6.2.3. Saving Environment Variables
Environment variables can be saved with the "saveenv" command. If the power of Armadillo-IoT is turned off without
performing the save, the environment variables set with setenv will be lost.
When using the QSPI bootloader environment variables are saved on the QSPI Flash. When using the SD bootloader,
environment variables are saved on the SD.
=> env default -a
=> saveenv
Figure 6.4. Restoring All Environment Variables to Default Values
6.2.4. Linux Kernel Boot Options
6.2.4.1. Typical Linux Kernel Boot Options
The Linux kernel has various startup options. For details, refer to the Linux reference books and the documentation
(Documentation/kernel-parameters.txt) included in the Linux kernel source code.
In this section, typical startup options that can be used with Armadillo-IoT are shown in Table 6.6, “Linux Kernel Boot
Table 6.6. Linux Kernel Boot Options Examples
Option
Specifier
Description
console=
Specify the initial console which outputs boot log etc.
In the following example ttymxc1 is specified for the console and 115200 for the baudrate.
console=ttymxc1,115200
root=
Specify the device on which the root file system is stored.
For the device, specify the device as recognized by the Linux kernel.
The initrd is set as the root file system as shown in the following example.
root=/dev/ram0
When storing the root file system on an SD card, specify the SD card's device file. In the following example, the second partition
of the microSD card is specified for the device.
root=/dev/mmcblk0p2
rootwait
Delay the mounting of the root file system until the device specified with "root=" becomes available.
mem
Specify the amount of memory available to the Linux kernel. Specify this when part of RAM is to be used as dedicated memory.
6.2.4.2. Setting Linux Kernel Boot Options
Linux kernel boot options can be specified with the "mmcargs" environment variable.
The default value of "mmcargs" is set to the following value.
Armadillo-IoT Gateway G3Product Manual - INTL
Bootloader Specifications
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