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Device Properties

A PCI device is required to provide a set of properties in its PCI configuration space. It may optionally supply FCode and run-time driver code in its expansion ROM. PCI devices without FCode and run-time driver code in ROM cannot be used during system startup.

The required device properties in PCI configuration space are

• vendor-ID
• device-ID
• class-code
• revision-number

For PCI boot devices there must be an additional property:

This property contains a pointer to the boot driver's image in the PCI card's expansion ROM. It is used in conjunction with the fcode-rom-offset property.

The Open Firmware FCode in a PCI device's expansion ROM must provide and install a driver property, as shown above, to have its driver appear in the Name Registry and be useful to the system during startup. It must also add its expansion ROM's base register to the reg property, so that system firmware can allocate address space when installing the driver.

To facilitate driver matching for devices with disk-based drivers, the FCode should provide a unique name property that conforms to the PCI specification. For further information, see PCI Open Firmware Drivers.