On Tue, Dec 3, 2013 at 4:24 AM, Jagan Teki <jagannadh.t...@gmail.com> wrote: > Hi, > > I have few question on Linux PCIe subsystem, I am trying to understand > the PCIe on ARM platform. > 1. Compared to PCI, PCIe have an extra port functionalists/services > which is implemented drivers/pci/pcie/* is it true?
Yes. > 2. PCIe root complex is same as Host controller drivers in linux > drivers/host/* Yes. > 3. As individual endpoint drivers are registered to pci_core as > pci_driver_register, then what is the common call for registering > individual HC driver to pci-core? The host controller-PCI core interface is not as mature as the pci_register_driver() interface. The basic interface is pci_scan_root_bus(). If you skim through the drivers in drivers/pci/host/* and drivers/acpi/pci_root.c, the interface to the PCI core will be fairly obvious. And you'll learn what the existing practices are in case you need to add or modify something. > 4. Can you list-down the basic and advanced functionalists supported > by HC driver in PCIe? The HC driver supplies struct pci_ops (functions to access config space), and the resources (bus numbers, MMIO aperture, I/O aperture) routed to the PCI/PCIe hierarchy below the host bridge. These are all supplied to pci_scan_root_bus(). There might also be chipset initialization and error handling logic in the HC driver. Pretty much everything else is generic and is supported by PCI core code. > 5. The PCIe port bus driver is common core? means no need to change w.r.t SOC? Yes. Bjorn -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
