title: How Pci driver works in Linux
body: <p>I'm trying to learn about how pci drivers works in Linux in PC environment but really find it difficult to go thorugh.There are few following statement which I like to understand before make a move.</p>
  
  <ol>
  <li><p>The PCI specification permits a system to host up to 256 buses.(buses = pci slots?)</p></li>
  <li><p>Each bus hosts up to 32 devices.</p></li>
  <li><p>Each device can be a multifunction board
  with a maximum of eight functions.(what exactly this line means?)</p></li>
  </ol>
  
  <p>On my PC can see only three pci slots (are these are called buses) and from each slots one irq lines is directed to cpu.</p>
  
  <p>It seems my understanding is quite wrong and thats why wanted to get in more views in.</p>