Booting is highly device-dependent, but here is an example using U-Boot on a BeagleBone Black and QEMU:.
The following U-Boot commands show how to boot Linux on a BeagleBone Black:
U-Boot# fatload mmc 0:1 0x80200000 zImage reading zImage 4606360 bytes read in 254 ms (17.3 MiB/s) U-Boot# fatload mmc 0:1 0x80f00000 am335x-boneblack.dtb reading am335x-boneblack.dtb 29478 bytes read in 9 ms (3.1 MiB/s) U-Boot# setenv bootargs console=ttyO0,115200 U-Boot# bootz 0x80200000 - 0x80f00000 Kernel image @ 0x80200000 [ 0x000000 - 0x464998 ] ## Flattened Device Tree blob at 80f00000 Booting using the fdt blob at 0x80f00000 Loading Device Tree to 8fff5000, end 8ffff325 ... OK Starting kernel ... [ 0.000000] Booting Linux on physical CPU 0x0 ...
Note that we set the kernel command line to console=ttyO0,115200
. That tells Linux which device to use for console output which, in this case, is the first UART on the board, device ttyO0
, at a speed of 115,200 bits per...