On Tuesday, July 19, 2016 10:40:16 AM CEST Jamie Lentin wrote: > On Mon, 18 Jul 2016, Arnd Bergmann wrote: > > > On Monday, July 18, 2016 11:44:24 AM CEST Thomas Petazzoni wrote: > >> > >> On Sun, 17 Jul 2016 22:41:35 +0200, Arnd Bergmann wrote: > >> > >>> I would assume that the PCIe port should work out of the box with the driver > >> > >> Unfortunately, no. The PCIe on Orion5x requires a workaround for > >> reading/writing the PCI configuration space. Instead of doing MMIO > >> accesses to PCIE_CONF_ADDR_OFF / PCIE_CONF_DATA_OFF, you must map a > >> MBus window, which provides a memory-mapped view of the PCI > >> configuration space. > >> > >> Definitely not impossible to implement, but the driver doesn't work > >> as-is. > > > > Ok. > > Unfortunately this isn't something I can test as the PCIe port on the SoC > doesn't go anywhere in my case. As I said, this wouldn't be a problem: we should consider the PCI and PCIe ports on this chip as completely separate anyway, so we can work on the drivers independently. > >>> We also don't seem to need any MBUS window setup for the I/O and > >>> memory spaces, which greatly simplifies the driver compared to the > >>> pci-mvebu one, it would be a fairly straightforward implementation > >>> based on pci-host-generic.c (which unfortunately just got way > >>> more complicated and might need to go on a diet). > >> > >> MBus windows are needed. See: > >> > >> mvebu_mbus_add_window_remap_by_id(ORION_MBUS_PCI_IO_TARGET, > >> ORION_MBUS_PCI_IO_ATTR, > >> ORION5X_PCI_IO_PHYS_BASE, > >> ORION5X_PCI_IO_SIZE, > >> ORION5X_PCI_IO_BUS_BASE); > >> mvebu_mbus_add_window_by_id(ORION_MBUS_PCI_MEM_TARGET, > >> ORION_MBUS_PCI_MEM_ATTR, > >> ORION5X_PCI_MEM_PHYS_BASE, > >> ORION5X_PCI_MEM_SIZE); > >> > >> in orion5x_setup_wins(). > > > > Ok, I was just looking at the wrong file, as they are set up from > > common.c, not pci.c. > > > >> Note that we already have some Orion5x converted to DT, and that use > >> PCI: board-rd88f5182.c is an example. So we could very well take Jamie > >> patches as-is, and move later to a DT-representation for PCI/PCIe. > > > > Ah, I thought all the DT users were moved to mach-mvebu. I agree > > this new patch isn't introducing anything we don't already have then, > > so we can just take it, but the conversion will not be nice when > > we do that. > > Yes, board-wnr854t.c is a clone of the existing board-rd88f5182.c. > Although I'd presume that it too would need late_initcall() or somesuch > mechanism to probe PCI once the GPIO controller is available. Deferred probing should be fine once the driver is migrated from pci_common_init() to registering the host bridge directly. Arnd -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
