TI Tools

U-Boot Toolkit

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Boot Configuration

Configure U-Boot environment variables or boot menu entries for your device.

Configuration Mode

uEnv.txt: Simple key=value variables for U-Boot environment. extlinux.conf: Structured boot menu with multiple boot options (distro boot).

Import Existing Configuration (Optional)

Upload an existing configuration file to load its settings into the editor

Boot Configuration

Time to wait before auto-boot (0 = instant boot)

Command executed to boot the system

Kernel command line parameters

Path to device tree blob relative to /boot

Space-separated list of overlay files to apply (e.g., for capes, add-on boards, or custom hardware)

Boot Media Configuration

SD card (0, 1) or eMMC device number

Format: device:partition (e.g., 1:2 for mmcblk1p2)

Directory containing kernel and device tree

Network Configuration (Optional)

Falcon Mode Configuration

Enable Falcon mode for fast boot (SPL directly loads Linux, bypassing U-Boot).

Boot Logo / Splash Screen

Upload and configure a custom boot logo to display during startup.

Preview & Export

Configuration Preview

# U-Boot Environment Configuration
# Generated by TI Tools U-Boot Toolkit

bootdelay=2
bootcmd=run findfdt; run envboot; bootflow scan -lb
bootargs=console=ttyS2,115200n8 earlycon=ns16550a,mmio32,0x02800000

About This Tool

The U-Boot Toolkit helps you configure U-Boot bootloader settings for Texas Instruments K3 processors. U-Boot is the bootloader responsible for initializing hardware and loading the Linux kernel.

What is uEnv.txt?

uEnv.txt is a text file containing U-Boot environment variables that are loaded during boot. It allows you to customize boot behavior without recompiling U-Boot. Uses simple key=value format.

What is extlinux.conf?

extlinux.conf is a structured boot menu configuration file used by U-Boot's distro boot feature. It allows multiple boot entries with different kernel arguments, similar to GRUB configuration.

What is Falcon Mode?

Falcon mode enables SPL (Secondary Program Loader) to directly load the Linux kernel, bypassing the full U-Boot stage. This significantly reduces boot time.

Boot Logo Support

U-Boot can display a custom splash screen during boot. The image must be in BMP format and loaded to memory before display.

Common Use Cases

  • Custom kernel arguments: Add kernel parameters like debug options, console settings, or root filesystem location
  • Boot menu (extlinux.conf): Create multiple boot entries for different configurations (production, debug, recovery)
  • Simple variables (uEnv.txt): Quick environment variable overrides for U-Boot settings
  • Network boot: Configure TFTP settings for booting kernel over network
  • Fast boot: Enable Falcon mode to reduce boot time by 1-2 seconds
  • Branding: Display company logo during boot process

File Placement

  • uEnv.txt: Place in the root of your boot partition (same directory as kernel Image)
  • extlinux.conf: Place in /boot/extlinux/extlinux.conf on your boot partition
  • Boot Logo: Save as splash.bmp in boot partition root

Resources