https://toorun.dev/tags/kernel-parameters/Recent content in kernel-parameters on toorun.devHugo -- gohugo.ioen-usTue, 28 Jul 2026 09:00:00 +0000https://toorun.dev/posts/bootdelay-option-values/Tue, 28 Jul 2026 09:00:00 +0000https://toorun.dev/posts/bootdelay-option-values/Bootdelay Option Values Explained What is Bootdelay? The bootdelay option is a U-Boot parameter that controls the delay (in seconds) before the bootloader automatically boots the kernel. It’s commonly used in embedded systems to give developers or users time to interrupt the boot process and access the U-Boot command-line interface. Common Bootdelay Values 0 (Zero Delay) Behavior: No delay—U-Boot immediately boots the kernel Use case: Production systems where interruption isn’t needed Trade-off: No opportunity to access U-Boot without serial console hacking 1-3 (Short Delay) Behavior: Brief window (1-3 seconds) to press a key and interrupt boot Use case: Development with faster iteration; some production systems Practical: 2 seconds is a common middle ground 5-10 (Standard Delay) Behavior: Comfortable window for manual intervention Use case: Embedded development; systems requiring frequent adjustments Standard: Many devices default to 5-10 seconds -1 (Wait Indefinitely) Behavior: U-Boot waits at the prompt until user input Use case: Lab environments; debugging; recovery scenarios Note: Blocks automated boot entirely Configuration Methods Via U-Boot Environment setenv bootdelay 2 saveenv Via Kernel Command Line Some systems support passing bootdelay through the kernel command line: