Dear all, We are developing a board using a Freescale P2020. This micro has three PCIexpress ports. 2 1xlane PCIe and 1 2xlane PCIe. We have been able to successfully use the PCIe interfaces. However, now we want to expand the number of PCIe slots connecting the 2xlane PCIe to a PCIe switch (89HPES6T5E). This switch offers a 2xlane upstream port and 4 1xlane downstream ports. The problem is that we do not really know how PCIe switches are managed in Linux. If any of you can recommend us some resources to read, we will appreciate it very much. If there is no information to read, let me describe our main problem. The question is that if I let u-boot scan the PCIe, the upstream and downstream ports are detected as well as the cards connected to the downstream port. However when u-boot launches Linux, this last just finds a device (the HPES6T5E), and none of the downstream ports or card connected to them. pci 0000:00:00.0: PCI bridge, secondary bus 0000:01 pci 0000:00:00.0: IO window: 0x00-0xffff pci 0000:00:00.0: MEM window: 0x80000000-0x9fffffff pci 0000:00:00.0: PREFETCH window: disabled pci 0000:00:00.0: enabling device (0106 -> 0107) pci 0001:02:00.0: PCI bridge, secondary bus 0001:03 pci 0001:02:00.0: IO window: 0x00-0xffff pci 0001:02:00.0: MEM window: 0xa0000000-0xbfffffff pci 0001:02:00.0: PREFETCH window: disabled pci 0001:02:00.0: enabling device (0106 -> 0107) pci 0002:05:00.0: PCI bridge, secondary bus 0002:06 pci 0002:05:00.0: IO window: disabled pci 0002:05:00.0: MEM window: 0xc0000000-0xc00fffff pci 0002:05:00.0: PREFETCH window: disabled pci 0002:04:00.0: PCI bridge, secondary bus 0002:05 pci 0002:04:00.0: IO window: 0x00-0xffff pci 0002:04:00.0: MEM window: 0xc0000000-0xdfffffff pci 0002:04:00.0: PREFETCH window: disabled pci 0002:04:00.0: enabling device (0106 -> 0107) However, if I do not let u-boot scan the bus, Linux finds five devices for the 89HPES6T5E and the card connected to the downstream ports. pci 0000:00:00.0: PCI bridge, secondary bus 0000:01 pci 0000:00:00.0: IO window: 0x00-0xffff pci 0000:00:00.0: MEM window: 0x80000000-0x9fffffff pci 0000:00:00.0: PREFETCH window: disabled pci 0000:00:00.0: enabling device (0106 -> 0107) pci 0001:02:00.0: PCI bridge, secondary bus 0001:03 pci 0001:02:00.0: IO window: 0x00-0xffff pci 0001:02:00.0: MEM window: 0xa0000000-0xbfffffff pci 0001:02:00.0: PREFETCH window: disabled pci 0001:02:00.0: enabling device (0106 -> 0107) pci 0002:06:02.0: PCI bridge, secondary bus 0002:07 pci 0002:06:02.0: IO window: disabled pci 0002:06:02.0: MEM window: disabled pci 0002:06:02.0: PREFETCH window: disabled pci 0002:06:03.0: PCI bridge, secondary bus 0002:08 pci 0002:06:03.0: IO window: disabled pci 0002:06:03.0: MEM window: disabled pci 0002:06:03.0: PREFETCH window: disabled pci 0002:06:04.0: PCI bridge, secondary bus 0002:09 pci 0002:06:04.0: IO window: disabled pci 0002:06:04.0: MEM window: disabled pci 0002:06:04.0: PREFETCH window: disabled pci 0002:06:05.0: PCI bridge, secondary bus 0002:0a pci 0002:06:05.0: IO window: disabled pci 0002:06:05.0: MEM window: 0xc0000000-0xc00fffff pci 0002:06:05.0: PREFETCH window: disabled pci 0002:05:00.0: PCI bridge, secondary bus 0002:06 pci 0002:05:00.0: IO window: disabled pci 0002:05:00.0: MEM window: 0xc0000000-0xc00fffff pci 0002:05:00.0: PREFETCH window: disabled pci 0002:04:00.0: PCI bridge, secondary bus 0002:05 pci 0002:04:00.0: IO window: 0x00-0xffff pci 0002:04:00.0: MEM window: 0xc0000000-0xdfffffff pci 0002:04:00.0: PREFETCH window: disabled pci 0002:04:00.0: enabling device (0106 -> 0107) pci 0002:05:00.0: enabling device (0000 -> 0002) pci 0002:06:05.0: enabling device (0000 -> 0002) /sys/bus/pci/devices # ls 0002:0a:00.0 0002:06:04.0 0002:06:02.0 0002:04:00.0 0000:00:00.0 0002:06:05.0 0002:06:03.0 0002:05:00.0 0001:02:00.0 I know that the problem could be in the u-boot, so I am trying to analyse its code also... but I think there could be something in Linux I am not taking into account yet. Thanks. Miguel Ángel -- 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
