Documentation/PCI/pciebus-howto.rst

5 The PCI Express Port Bus Driver Guide HOWTO
14 This guide describes the basics of the PCI Express Port Bus driver
16 register/unregister with the PCI Express Port Bus Driver.
19 What is the PCI Express Port Bus Driver
22 A PCI Express Port is a logical PCI-PCI Bridge structure. There
23 are two types of PCI Express Port: the Root Port and the Switch
24 Port. The Root Port originates a PCI Express link from a PCI Express
25 Root Complex and the Switch Port connects PCI Express links to
26 internal logical PCI buses. The Switch Port, which has its secondary
28 switch's Upstream Port. The switch's Downstream Port is bridging from
32 A PCI Express Port can provide up to four distinct functions,
34 PCI Express Port's services include native hotplug support (HP),
40 Why use the PCI Express Port Bus Driver?
45 Express Port is a PCI-PCI Bridge device with multiple distinct
49 For example, if the PCI Express Root Port native hotplug service
50 driver is loaded first, it claims a PCI-PCI Bridge Root Port. The
52 Port. In other words, it is impossible to have multiple service
57 having a PCI Express Port Bus driver, which manages all populated
60 advantages of using the PCI Express Port Bus driver are listed below:
63     a PCI-PCI Bridge Port device.
69     Port devices.
71   - Manage and distribute resources of a PCI-PCI Bridge Port
74 Configuring the PCI Express Port Bus Driver vs. Service Drivers
77 Including the PCI Express Port Bus Driver Support into the Kernel
80 Including the PCI Express Port Bus driver depends on whether the PCI
82 automatically include the PCI Express Port Bus driver as a kernel
91 PCI Express Port Bus Driver. To meet the PCI Express Port Bus Driver
96 register its service with the PCI Express Port Bus driver (see
101 the PCI Express Port Bus driver from loading a service driver.
113 necessary since these calls are executed by the PCI Port Bus driver.
179 Since all service drivers of a PCI-PCI Bridge Port device are
193 switch interrupt mode on its device. The PCI Express Port Bus driver
197 is passed in when the PCI Express Port Bus driver probes each service