Peripheral Component Interconnect (kurz PCI) ist ein Bus zur leichten Verbindung von Peripheriegeräten mit mit der CPU.

== Konfigurations-Register ==
Jedes PCI-Gerät besitzt ein Konfigurations-Register, welches 256 Byte groß ist. Gelesen und beschrieben wird es 32bit-weise mithilfe eines Adress-I/O-Ports (0xCF8) und eines Daten-I/O-Ports (0xCFC).

=== Aufbau des Adress-I/O-Ports ===
{| border="1"
! 31         || 30-24      || 23-16     || 15-11        || 10-8            || 7-0
|-
| Enable Bit || Reserviert || Busnummer || Gerätenummer || Funktionsnummer || Registernummer
|}
<br />

=== Aufbau des Konfigurations-Register ===
{| border="1"
! Register || 31-24       || 23-16         || 15-8          || 7-0
|-
| 00       || colspan="2" | Device ID      || colspan="2" | Vendor ID
|-
| 04       || colspan="2" | Status         || colspan="2" | Command
|-
| 08       || Classcode   || Subclass      || colspan="2" | Revision ID
|-
| 0x0C     || BIST        || Header Type   || Latency Timer || Cache Line Size
|-
| 0x10     || colspan="4" | Base Address 0 (BAR0)
|-
| 0x14     || colspan="4" | Base Address 1 (BAR1)
|-
| 0x18     || colspan="4" | Base Address 2 (BAR2)
|-
| 0x1C     || colspan="4" | Base Address 3 (BAR3)
|-
| 0x20     || colspan="4" | Base Address 4 (BAR4)
|-
| 0x24     || colspan="4" | Base Address 5 (BAR5)
|-
| 0x28     || colspan="4" | Cardbus CIS Pointer
|-
| 0x2C     || colspan="2" | Subsystem ID || colspan="2" | Subsystem Vendor ID
|-
| 0x30     || colspan="4" | Expansion ROM base address
|-
| 0x34     || colspan="4" | Reserviert
|-
| 0x38     || colspan="4" | Reserviert
|-
| 0x3C     || Max Latency || Min Grant || Interrupt Pin     || Interrupt Line
|}
<br />

=== Codebeispiel ===
<c>
#define PCI_CONFIG_DATA    0xCFC
#define PCI_CONFIG_ADDRESS 0xCF8

/**
 * Liest ein Dword aus einem PCI-Konfigurations-Register
 *  @param bus Bus
 *  @param dev Gerät
 *  @param func Funktion
 *  @param offset Registernummer
 *  @return Register content
 */
int pci_config_readd(int bus,int dev,int func,int offset) {
  int val;
  int address = 0x80000000|(bus<<16)|(dev<<11)|(func<<8)|(offset&0xFC);
  outl(PCI_CONFIG_ADDRESS,address);
  val = inl(PCI_CONFIG_DATA);
  return val;
}

/**
 * Schreibt ein Dword in in ein PCI-Konfigurations-Register
 *  @param bus Bus
 *  @param dev Gerät
 *  @param func Funktion
 *  @param offset Registernummer
 *  @param val Wert zum Schreiben
 */
void pci_config_writed(int bus,int dev,int func,int offset,int val) {
  int address = 0x80000000|(bus<<16)|(dev<<11)|(func<<8)|(offset&0xFC);
  outl(PCI_CONFIG_ADDRESS,address);
  outl(PCI_CONFIG_DATA,val);
}
</c>

== Classcodes ==
{| border="1"
! Class     || Beschreibung
|-
| 0x00      || [[#Subclasses_-_Pre_2.0 | Alle Geräte die gebaut wurden bevor Classcodes eingeführt wurden ]]
|-
| 0x01      || [[#Subclasses_-_Massenspeicher | Massenspeicher]]
|-
| 0x02      || [[#Subclasses_-_Netzwerk-Controller | Netzwerk-Controller}}
|-
| 0x03      || [[#Subclasses_-_Bildschirm-Controller | Bildschirm-Controller]]
|-
| 0x04      || [[#Subclasses_-_Multimedia-Geräte | Multimedia-Geräte]]
|-
| 0x05      || [[#Subclasses_-_Speicher-Controller | Speicher-Controller]]
|-
| 0x06      || [[#Subclasses_-_Bridge-Geräte | Bridge-Geräte]]
|-
| 0x07      || [[#Subclasses_-_Controller zur einfachen Kommunikation | Controller zur einfachen Kommunikation]]
|-
| 0x08      || [[#Subclasses_-_System-Peripherie | System-Peripherie]]
|-
| 0x09      || [[#Subclasses_-_Input-Geräte | Input-Geräte]]
|-
| 0x0A      || [[#Subclasses_-_Docking-Stationen | Docking-Stationen]]
|-
| 0x0B      || [[#Subclasses_-_Prozessoren | Prozessoren]]
|-
| 0x0C      || [[#Subclasses_-_Seriell-Bus-Controller | Seriell-Bus-Controller]]
|-
| 0x0D-0xFE || Reserviert
|-
| 0xFF      || Sonstige
|}
<br />

=== Subclasses - Pre 2.0 ===
{| border="1"
! Subclass || Beschreibung
|-
| 0x00     || Alle nicht-VGA-Geräte
|-
| 0x01     || VGA-Geräte
|}
<br />

=== Subclasses - Massenspeicher ===
{| border="1"
! Subclass || Beschreibung
|-
| 0x00     || SCSI
|-
| 0x01     || IDE
|-
| 0x02     || Floppy
|-
| 0x03     || IPI
|-
| 0x04     || RAID
|-
| 0x80     || Anderer Massenspeicher
|}
<br />

=== Subclasses - Netzwerk-Controller ===
{| border="1"
! Subclass || Beschreibung
|-
| 0x00     || Ethernet
|-
| 0x01     || Token Ring
|-
| 0x02     || FDDI
|-
| 0x03     || ATM
|-
| 0x80     || Anderer Netzwerk-Controller
|}
<br />

=== Subclasses - Bildschirm-Controller ===
{| border="1"
! Subclass || Beschreibung
|-
| 0x00     || VGA-Kompatibel
|-
| 0x01     || XGA
|-
| 0x80     || Anderer Bildschirm-Controller
|}
<br />

=== Subclasses - Multimedia-Geräte ===
{| border="1"
! Subclass || Beschreibung
|-
| 0x00     || Video-Gerät
|-
| 0x01     || Audio-Gerät
|-
| 0x80     || Anderes Multimedia-Gerät
|}
<br />

=== Subclasses - Speicher-Controller ===
{| border="1"
! Subclass || Beschreibung
|-
| 0x00     || RAM
|-
| 0x01     || Flash-Speicher
|-
| 0x80     || Anderer Speicher
|}
<br />

=== Subclasses - Bridge-Geräte ===
{| border="1"
! Subclass || Beschreibung
|-
| 0x00     || Host/PCI-Bridge
|-
| 0x01     || PCI/ISA-Bridge
|-
| 0x02     || PCI/EISA-Bridge
|-
| 0x03     || PCI/MicroChannel-Bridge
|-
| 0x04     || PCI/PCI-Bridge
|-
| 0x05     || PCI/PCMCIA-Bridge
|-
| 0x06     || PCI/NuBus-Bridge
|-
| 0x07     || PCI/CardBus-Bridge
|-
| 0x80     || Anderer Bridge-Typ
|}
<br />

=== Subclasses - Controller zur einfachen Kommunikation ===
{| border="1"
! Subclass || Beschreibung
|-
| 0x00     || Serielle Schnittstelle
|-
| 0x01     || Parallelport
|-
| 0x80     || Andere
|}
<br />

=== Subclasses - System-Peripherie ===
{| border="1"
! Subclass || Beschreibung
|-
| 0x00     || [[Programmable Interrupt Controller]]
|-
| 0x01     || [[Direct Memory Access]]
|-
| 0x02     || Timer
|-
| 0x03     || [[Realtime Clock]]
|-
| 0x80     || Andere System-Peripherie
|}
<br />

=== Subclasses - Input-Geräte ===
{| border="1"
! Subclass || Beschreibung
|-
| 0x00     || Tastatur
|-
| 0x01     || Digitizer (Stift)
|-
| 0x02     || Maus
|-
| 0x80     || Anderes Input-Gerät
|}
<br />

=== Subclasses - Docking-Stationen ===
{| border="1"
! Subclass || Beschreibung
|-
| 0x00     || Normale Docking-Station
|-
| 0x80     || Andere Docking-Station
|}
<br />

=== Subclasses - Processors ===
{| border="1"
! Subclass || Beschreibung
|-
| 0x00     || 386
|-
| 0x01     || 486
|-
| 0x02     || Pentium
|-
| 0x10     || Alpha
|-
| 0x20     || PowerPC
|-
| 0x40     || Co-Processor
|-
|}
<br />

=== Subclasses - Seriell-Bus-Controller ===
{| border="1"
! Subclass || Beschreibung
|-
| 0x00     || Firewire (IEEE 1394)
|-
| 0x01     || ACCESS-Bus
|-
| 0x02     || SSA (Serial Storage Architecture)
|-
| 0x03     || [[USB]] (Universal Serial Bus)
|}
<br />



== Weblinks ==
* [http://pci-ids.ucw.cz/iii/ Linux PCI ID Repositorium] - Enthält viele VendorIDs und die dazugehörigen DeviceIDs