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Documentation is now handled by the same processes we use for code: Add something to the Documentation/ directory in the coreboot repo, and it will be rendered to https://doc.coreboot.org/. Contributions welcome!
This page explain the workings of the CMOS layout file. The CMOS layout file can be linked into a board specific environment. By creating the cmos.layout file in the board directory. and set the HAVE_OPTION_TABLE in the Kconfig file of the board.
The CMOS layout file must contain the following sections;
The hash (#) character is the comment prefix, all characters until the eof of line are treated as comment.
Each line in the the enumerations section is contructed as follows;
<config-id> <value> <label>
The paramater <config-id> is the same value as the <config-id> from the entries section.
The paramater <value> is the value that get stored at the bit location defined in the entries section, where that config-id is being used.
The paramater <label> is the label for displaying in the the presentation layer.
1 0 Disable 1 1 Enable 5 0 115200 5 1 57600 5 2 38400 5 3 19200 5 4 9600 5 5 4800 5 6 2400 5 7 1200
The checksums section has one variable with three parameters;
checksum <startbit> <endbit> <start-of-checksumbit>
The <startbit> parameter is the bit position where the calculation of the checksum starts from.
The <endbit> parameter is the bit position there the calculation of the checksum starts on.
The <start-of-checksumbit> parameter is the bit position there the checksum will be stored, there must be space for 16 bits of checksum data.
checksum 392 983 984