The PF driver of a SR-IOV device is used to manage the Physical Function (PF) of an SR-IOV capable device. A PCI Function that supports the SR-IOV capabilities is defined in the SR-IOV specification. A PF contains the SR-IOV capability structure and is used to manage the SR-IOV functionality. PFs are fully featured PCIe functions which can be discovered, managed, and manipulated like any other PCIe device. PFs have full configuration resources, and can be used to configure or control the PCIe device. A PF driver exhibits the following characteristics:
Visible in Root Domain only
May or may not possess data movement capabilities. The PF driver should function even in SR-IOV mode.
Controls the enabling and disabling of the SR-IOV capability through APIs provided by the Oracle Solaris IOV Framework.
The number of VFs to be configured for a given PF is determined by the system administrator. This number defined either in Machine Descriptors (MD) on the Sparc OVM platforms or a configuration file in the bare metal environment.
The PF driver enables the VFs during the attachment phase by calling the Oracle Solaris IOV framework through the DDI interface. If the PF driver does not enable VFs during attachment, the Oracle Solaris IOV framework will attempt to configure VFs after the attachment as long as the driver callback flags indicates that the driver has IOV capability is supported.
PFs can enable and disable each associated VF individually through a device specific mechanism