[Verse 1] Power button pressed, the silicon awakens First-stage loader checks the flash partition ROM code validates signatures and tokens Bootloader emerges from its dark dominion U-Boot or GRUB takes control of the machine Scanning memory maps for kernel placement clean [Chorus] DTB in memory, flattened tree structure Register R2 holds the magic pointer Bootloader whispers secrets to the kernel Device tree blob becomes the system's interpreter Physical address passed through calling convention Hardware topology mapped for comprehension [Verse 2] Firmware unravels the device tree binary Clocks and interrupts described in hierarchy GPIO pins and buses catalogued precisely Memory controllers configured so nicely Kernel expects the tree at designated space Bootloader plants it in that sacred place [Chorus] DTB in memory, flattened tree structure Register R2 holds the magic pointer Bootloader whispers secrets to the kernel Device tree blob becomes the system's interpreter Physical address passed through calling convention Hardware topology mapped for comprehension [Bridge] Command line parameters flow through registers ATAGS or device tree, architecture differs ARM uses R0, R1, R2 for the handoff dance x86 leverages different parameter stance Zero in R0, machine type in R1 DTB physical address when setup is done [Verse 3] Kernel decompression reads the flattened nodes Properties and compatible strings decode Memory reservation maps protect the blob DMA coherent pools avoid the memory rob Early console output needs that tree data Before the scheduler becomes kernel strata [Chorus] DTB in memory, flattened tree structure Register R2 holds the magic pointer Bootloader whispers secrets to the kernel Device tree blob becomes the system's interpreter Physical address passed through calling convention Hardware topology mapped for comprehension [Outro] From power-on reset to userspace ascension Device trees guide each hardware dimension Bootloader legacy lives in kernel memory Teaching silicon how to dance in harmony
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