Phytec L-1017e.A3 i.MX 8M Plus, Руководство пользователя

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L-1017e.A3 i.MX 8M Plus BSP Manual
Manufacturer: PHYTEC
Version:
Devicetree overlay: imx8mp-phycore-no-spiflash.dtbo
Other information: SPI flash not populated on SoM
If the EEPROM data is not available, no device tree overlays are applied and the default status " okay " is
preserved. To prevent running the extension command during boot the ${no_extensions} variable can be set to 1 in
the bootloader environment.
u-boot=> setenv no_extensions 1
u-boot=> saveenv
U-boot External Environment
During the start of the linux kernel the external text environment bootenv.txt text file will be loaded from the boot
partition of an MMC device or from tftp. The main intention of this file is to store the ${overlays} variable. This makes
it easy to pre-define the overlays in Yocto depending on the machine used. The content from the file is defined in
the Yocto recipe
bootenv found in meta-phytec: https://git.phytec.de/meta-phytec/tree/recipes-bsp/bootenv?
h=hardknott
Other variables can be set in this file. They will overwrite the existing settings in the environment. But only variables
evaluated after the boot command is issued can be overwritten such as ${nfsroot} or ${mmcargs}. Changing other
variables in that file will not have an effect. See the usage during
netboot as an example.
If the external environment can not be loaded the boot process will be anyway continued with the values of the
existing environment settings.