Hello, Im trying to remove and insert a carrier PCI Express card that contains an endpoint card from an ATCA system. The PCI express card that contains the PCIe Swittch (PEX 8696 from PLX) is attached to an OSS (One Stop System) card that contains the Root Complex (PEX 8733 from Plx) via a PCI Express cable. The OSS card is a x16 PCI Express card placed in the PCIE motherboard slot from a computer running Redhat 6.3 with real time kernel version 3.0.9.rt. When I hotplug, remove or insert, the endpoint connected to the carrier card everything goes well with the removal and insertion procedures (also the device drivers are unloaded and loaded from the system when I run "remove" and "rescan" commands through an hotplug developed service for this purpose). Problems arrive when I try to hotplug (hotswap to be precise) the carrier card containing PEX 8696 (PCIe Switch). I can perform the operation once by removing and inserting the PCI Express cable connected between carrier and OSS cards (and consequently unloading and loading the corresponding carrier device drivers). When performing the same operation for the second time I can remove the PCI express cable and unload carrier device drivers again but the insert procedure (and device drivers load operation) no longer occur because PCI Express upstream (from PEX 8733, the root complex point of view) link does not seems to happen (signalled by a LED indicator placed in the carrier card). There was a test in which I could manage to perform the above operation 3 times and in the 4th insertion the same happened (but in this test I opened the Plx editor software between each operation of removal and insertion to capture a snapshot of the PEX 8733 upstream registers to track and isolate the problem). So I suppose that somehow when the link negotiation procedure fails the hotswap procedure no longer occurs. Also when I run "lspci" command PEX 8696 no longer appears (of course) and the branch of the entire PCI express tree (path until the FPGA endpoint) reaches only until the PEX 8733 downstream port. Can anybody explain what is happening and what can I do to restore the PCI express link each time I perform the hotswap procedure? Also, from the registers snapshot I could see that somehow when this happens there is always TLP packet that is waiting to be delivered (pending I suppose) but I don't know if this is an hardware or software issue. Regards, Paulo. -- To unsubscribe from this list: send the line "unsubscribe linux-pci" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
