On 06/02/2017 16:54, Mason wrote: > My platform ( arch/arm/mach-tango ) provides a PCIe controller from PLDA. > > I do have access to a driver that works for a few PCIe boards, but it's > an ancient out-of-tree driver (targeting v3.4). Also, I'm not sure it > follows the best-practice guidelines (e.g. it hard-codes a few > work-arounds directly in drivers/pci/probe.c) > > If I understand correctly, while PCIe is a standard, it is not codified > as much as USB (XHCI) or SATA (AHCI), which means the register layout > (and possibly other things) are left up to the integrator? Which means > there cannot be some kind of "generic" driver that works for a random > PCIe controller? > > I guess my main question is: do you have pointers on getting started > writing a PCIe driver good enough for upstream? > > Is Documentation/PCI/PCIEBUS-HOWTO.txt still a relevant resource? > > Are there good resources to get up to speed on the PCIe terminology? I'm also wondering: in many Linux subsystems, there are often several drivers of different quality; some are obsolescent and have not been updated in a while, while some are recent and follow all the latest best-practice guidelines (and the rest is somewhere in the middle). Are there 1 or 2 very good PCIe drivers to take as examples as good starting points? (Perhaps a simple driver, and a more complex driver.) Does anyone know if any SoC with a driver upstream is using a PLDA controller? Regards.
