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pcicfg

The pcicfg command access PCI configuration space.

Command Format

pcicfg bus device subfunc register

where:

bus PCI bus to access
device PCI device to access
subfunc PCI subfunction to access
register PCI register to access

Functional description

The pcicfg command is used to access the PCI configuration space in the given bus. The command takes four arguments, the bus number, the device number, the subfunction number and the first register to access. The register number must be 32 bit aligned and all accesses are made as 32 bit read and writes. When executing the command an interactive mode is entered. The register number along with the current contents of the configuration register is displayed. The user can then enter one of the following commands:

Item Action
expression value to be stored
= reread the current location
<cr> forward to next address
- back to previous address
^ back to previous address
. exit interactive mode

If an expression is given, the register displayed will be written with the new value and the next register will be displayed.

Values are always displayed and entered in little endian or the native PCI endian. What this mean is that bytes does not have to be swapped if the target is a big endian target.

Environment

The command uses no environment variable.

See Also

The pciscan command.