Kernel command line arguments

To allow some flexibility of the kernel main features without compiling it each time, it is possible to use "command line arguments". These arguments are passed to the kernel from the bootloader, as a list of key=value strings.

For default sh3 target, command line arguments are expected at address 0x88000000 (first physical RAM page), and 1024 bytes are reserved for them.

Supported arguments

Here is a list of supported arguments, possible values, and a description of them.

• console=<device> : set the device used by the kernel console (for displaying printk() logs). Default is the first virtual terminal, tty1.

  • console=tty<n> : use the VT n
  • console=ttyUSB0 : use the USB CDC/ACM device (emulation of a serial communication through USB device protocol)
  • others may be added later

• loglevel=<level> : set the dynamic log level, used to determine which messages from printk() are displayed on the console. A value of 0 display everything (including debug messages), and a value of 7 avoid any message to be displayed (even critical error messages!). Please see utils/log.h for defintion of each level.

• init=</absolute/path> : set the init executable file path, which is the first user space program loaded by the kernel as soon as it is initialized