Re: Understanding lspci output

From: Robert Hancock
Date: Wed Oct 17 2007 - 19:39:02 EST


John Sigler wrote:
4. Does the system have a PCI-X bus?

Yes, the devices on bus 01 are PCI-X devices, so there is a PCI-X bus.

I thought PCI-X devices could operate on a PCI bus? If that is true, then the presence of a PCI-X device would not necessarily imply the presence of a PCI-X bus, right?

There are no external PCI-X slots in the system, only 2 PCI slots.
The 4 NICs are integrated to the motherboard.
http://advantech.com/products/1U-Rackmount-Intel-Pentium-4Processor-based-Platform-with-4PCI-LAN-Ports-2-PCI-Expansion-Slots/mod_1-23A2W4.aspx

The NICs are all PCI-X devices and they report "64bit+" so they will be running on a PCI-X bus internally.



2. Do any of the PCI buses support 66 MHz operation?

Yes, PCI-X does.

So the 01:0f.0 device (Multimedia video controller) is on the same bus as the 4 PCI-X devices and will have to share the bus bandwidth?

Does 66MHz+ in the Status line means this device is running at 66 MHz?

I believe so.


3. Do any of the PCI slots support 64-bit data path?

This cannot be inferred from the lspci output -- there is no way how to
tell if a bus has physical slots or it exists only internally.

Can I use lspci to see whether a specific PCI device is using a 64-bit data path? (e.g. the 01:0f.0 device)

The "Multimedia video controller: DekTec Digital Video B.V. DTA-105" doesn't report PCI-X capabilities. And looking at the card on their web site, it does not have a 64-bit extension, so it doesn't support 64-bit.

--
Robert Hancock Saskatoon, SK, Canada
To email, remove "nospam" from hancockr@xxxxxxxxxxxxx
Home Page: http://www.roberthancock.com/

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