Linux PCI Initialization

  The PCI initialisation code in Linux is broken into three logical parts:

PCI Device Driver

This pseudo-device driver searches the PCI system starting at Bus 0 and locates all PCI devices and bridges in the system. It builds a linked list of data structures describing the topology of the system. Additionally, it numbers all of the bridges that it finds.

PCI BIOS

This software layer provides the services described in [4, PCI BIOS ROM specification,]. Even though Alpha AXP does not have BIOS services, there is equivalent code in the Linux kernel providing the same functions,

PCI Fixup

System specific fixup code tidies up the system specific loose ends of PCI initialization.

The next subsections describe these processes in more detail.

• The Linux Kernel PCI Data Structures
• The PCI Device Driver
  • Configuring PCI-PCI Bridges - Assigning PCI Bus Numbers
• PCI BIOS Functions
• PCI Fixup
  • Finding Out How Much PCI I/O and PCI Memory Space a Device Needs
  • Allocating PCI I/O and PCI Memory to PCI-PCI Bridges and Devices