Hi Onkar. On Friday 01 February 2008 11:34:37 Onkar wrote: > I am foxed with the lspci output > > " lspci is a utility for displaying information about all PCI buses > in the system and all devices connected to them. " > > that means all the devices - devices for which drivers are available and > devices for which kernel has to offer no drivers - > if there are no dirvers how is Linux able to detect the device in the first > place ????? In a nutshell : You don't need a driver for a PCI device in order to get the kind of information from the device that lspci does. You only need a driver for the PCI Host Interface on the system and that is almost always present if there is a grown up OS running on it. A bit more elaboration : PCI is a standardised busing protocol. A compliant PCI device is supposed to respond with what is known as a PCI Configuration Header in response to a type of interaction known as a PCI Configuration Cycle that is made by a special device called a PCI Host Interface. The Configuration Header provides a set of device specific attributes which is exactly what lspci is capable of formatting and displaying. Most systems have a PCI Host Interface and this is the only entity for which a driver is needed in order to perform Configuration Cycles on the PCI bus to "learn" about connected (and compliant) PCI devices. This process is called Enumeration. Hope that helps. Cheerio, Robin -- To unsubscribe from this list: send an email with "unsubscribe kernelnewbies" to ecartis@xxxxxxxxxxxx Please read the FAQ at http://kernelnewbies.org/FAQ
