Hello, There are two revisions of our PCI Express controller. Rev 1 did not support the following features: 1) legacy PCI interrupt delivery (INTx signals) 2) I/O address space Internally, someone stated that such missing support would prevent some PCIe cards from working with our controller. Are there really modern PCIe cards that require 1) and/or 2) to function? Can someone provide examples of such cards, so that I may test them on both revisions? I was told to check ath9k-based cards. Any other examples? Looking around, I came across this thread: http://lists.infradead.org/pipermail/linux-arm-kernel/2016-March/418254.html "i.MX6 PCIe: Fix imx6_pcie_deassert_core_reset() polarity" IIUC, although some PCIe boards do support MSI, the driver might not put in the work to use that infrastructure, and instead reverts to legacy interrupts. (So it is a SW issue, in a sense.) Regards.
