%PCI
%Thadeu Cascardo

# PCI Basics

* Addressing: bus, device and function
* Configuration space
* "Firmware" (BIOS, PROM, etc) sets up the devices

# Files and Tools

* /sys/bus/pci/
	- devices/*/
		* vendor
		* device
		* class
		* config
* /proc/bus/pci/
* /proc/bus/pci/devices
* lspci

# Configuration space

* 64 standardized bytes
* Identifiers
* Base Addresses
* IRQs
* Little-endian

# PCI IDs

* struct pci\\_device\\_id
	- vendor
	- device
	- subvendor
	- subdevice
	- class
	- class\\_mask
	- driver\\_data
* PCI\\_ANY\\_ID
* PCI\\_DEVICE
* PCI\\_DEVICE\\_CLASS
* DEFINE\\_PCI\\_DEVICE\\_TABLE

# PCI Drivers

* struct pci\\_driver
	- name
	- id\\_table
	- probe
	- remove
* pci\\_register\\_driver
* pci\\_unregister\\_driver

# PCI Device

* struct pci\\_dev
* pci\\_enable\\_device
* pci\\_disable\\_device
* pci\\_set\\_drvdata

# Accessing the configuration space

* pci\\_read\\_config\\_byte(dev, where, *val)
* pci\\_read\\_config\\_word(dev, where, *val)
* pci\\_read\\_config\\_dword(dev, where, *val)
* pci\\_write\\_config\\_byte(dev, where, val)
* pci\\_write\\_config\\_word(dev, where, val)
* pci\\_write\\_config\\_dword(dev, where, val)

# PCI Resources

* pci\\_resource\\_start(dev, bar)
* pci\\_resource\\_end(dev, bar)
* pci\\_resource\\_len(dev, bar)
* pci\\_resource\\_flags(dev, bar)
	- IORESOURCE\\_IO
	- IORESOURCE\\_MEM

# Using PCI devices

* pci\\_request\\_regions
* pci\\_release\\_regions
* pci\\_iomap
* pci\\_ioremap\\_bar
* struct pci\\_dev
	- irq