Table of Contents
Advertisement
U-Boot standard environment variables are set up for the SMARC_sAMX8X module as shown below.
Table 12: Standard Environment Variables
Variable
Value
baudrate
115200
bootcmd
Run mmcboot || run sdboot || run usbboot ||
run netboot || run bootfailed
bootdelay
3
ethprime
FEC0
loadaddr
0x80800000
A typical user modification would be to set the variable "bootcmd" to change OS boot commands.
7.6. Bootloader Environment Update
On the SMARC-sAMX8X it is possible to update the U-Boot environment separately.
This enables the user to either update from a previous version of the official Kontron sAMX8X U-Boot environment
(default U-Boot settings), or restore the default in case of problems.
Update procedure:
Download the official sAMX8X U-Boot environment from the Kontron EMD Customer Section.
For Release R10 of the sAMX8X U-Boot, the file is called 'sMX8X-env-r10.bin'.
Put the file into the root directory of a FAT or EXT formatted USB drive.
Start the sAMX8X system and stop the boot process at the U-Boot prompt.
Run the following commands to load the file and flash it into the correct flash memory address (example
for R10):
usb start && load usb 0:1 $loadaddr sMX8X-env-r10.bin
sf probe && sf update $loadaddr 0x0c0000 $filesize
After reset the updated environment will be active.
7.7. Kontron Bootloader Environment Extensions
To support SMARC_sAMX8X board properly, Kontron adds some environment variables to the standard set of
variables provided by mainline U-Boot. These variables are shown below.
Table 13: Bootloader Environment Extensions
Variable
Value
boot_sel
Depends on
BOOT_SEL
lines
core_variant
d
s
eth1addr
From EEPROM
ethaddr
From EEPROM
fdt_addr
0x83000000
panel
Default: ld101
www.kontron.com
Description
BOOT_SEL lines from carrier are evaluated during startup and
boot_sel is set appropriately. See chapter 0 Bootloader Boot Source
for more detail
Set to "s" for i.MX8XS module, "d" for i.MX8XD module.
Ethernet port FEC1 MAC address
Ethernet port FEC0 MAC address
Memory location for device tree blob
Describes the panel type attached to the module. It is used to select
SMARC-sAMX8X User Guide. Rev. 1.1
Description
Serial line baudrate
Try booting (in this order) from eMMC, SD
card, USB, network
Wait 3 seconds before executing bootcmd
Use Ethernet port FEC0 as default
Default memory location for OS boot
// 42
Advertisement
Table of Contents
