In the /boot/device.hints file, two parameters, port and irq, must be specified to reflect adapter hardware settings. Another parameter flags can be specified to provide additional configuration as an option.
The port parameter specifies a base I/O port address of the adapter. It must match with the hardware setting of the adapter. The port may be left unspecified by removing
from the file. In that case, the driver tries to detect the hardware setting of the I/O address automatically. This feature may not work with some adapter hardware.
The irq parameter specifies an IRQ number used by the adapter. It must match the hardware setting of the adapter. Irq may be left unspecified by removing
from the file. in that case, the driver tries to detect the hardware setting of the IRQ automatically. This feature may not work on some adapters.
The flags is a numeric value which consists of a combination of various device settings. The following flags are defined in the current version. To specify two or more settings for a device, use a numeric sum of each flag value. Flag bits not specified below are reserved and must be set to 0. Actually, each bit is either just ignored by the driver, or tested and used to control undocumented features of the driver. Consult the source program for undocumented features.