Parameter line interface

The kernel supports processing of parameters that are provided by the boot loader. The parameter string is a NUL-terminated ASCII string that contains space-separated words or <#437#> <#409#> variable<#409#>=<#410#> value<#410#><#437#> pairs. A description of how they are interpreted can be found in the section of the user's guide labeled ``The boot prompt''. The following descriptor has to be set up to pass a parameter string to the kernel:
0x90020
the magic number 0xA33F.
0x90022
the offset of the first byte of the parameter line relative to 0x90000.
The boot loader composes the parameter line from the command line, from the options sector and from some internally generated prefixes (typically 2auto;SPM_quot; and 3BOOT_IMAGE=;SPM_quot;), as follows:

#displaymath603#

Example:
Command line: 4vmlinuz root=802;SPM_quot;
Options sector: 5root=801 ro;SPM_quot; yields 6BOOT_IMAGE=vmlinuz root=801 ro root=802;SPM_quot; Because parameter line options can typically be overridden, the first 7root;SPM_quot; option is ignored by the kernel.