On 2014/7/24 14:35, John wrote: > Hi > I am trying to write a PCIe linux device driver to handle PCIe switches and > endpoints that show up after the Redhat 6.4 linux is already up and running. > > If I try to allocate the resources of the PCIe switches & endpoints between > 0xF4000000 and 0xF47FFFFF everything works fine .. But this range is quite > full with other devices, so I tried to extend this range to start from > 0xF0000000, or from 0xD0000000 the allocation works fine, but I am unable to > access devices in the extended range > > Anybody has idea why I am unable to use the complete 3G - 4G address range ? > Is it related to some ACPI boot configuration that need to be changed, I can > see in my dmesg > > pci_root PNP0A08:00: host bridge window [mem 0xf4000000-0xf7ffffff] > pci_root PNP0A08:00: host bridge window [io 0x1000-0x7fff] > pci_root PNP0A08:00: host bridge window [io 0x0000-0x03af] > pci_root PNP0A08:00: host bridge window [io 0x03e0-0x0cf7] > pci_root PNP0A08:00: host bridge window [io 0x0d00-0x0fff] > pci_root PNP0A08:00: host bridge window [mem 0xfed00000-0xfed03fff] > pci_root PNP0A08:00: host bridge window [mem 0xfed40000-0xfed44fff] > pci_root PNP0A08:00: host bridge window [io 0x03b0-0x03bb] > pci_root PNP0A08:00: host bridge window [io 0x03c0-0x03df] > pci_root PNP0A08:00: host bridge window [mem 0x000a0000-0x000bffff] > pci_root PNP0A08:01: host bridge window [mem 0xf8000000-0xfbffffff] > pci_root PNP0A08:01: host bridge window [io 0x8000-0xffff] > > Is there a reason for this limited range ? Is it processor dependant ? Yes, you should use the resource range in host bridge window, or you won't request resource success. PCI hostbridge retrieve the host bridge window from ACPI _CRS method, if _CRS is not exist, PCI may use global resource iomem_resource and ioport_resource as its hostbridge window. BIOS is responsible for the _CRS resource range report. BTW, you can append the pci=nocrs in command line and try again. Thanks! Yijing. > > Thanks > > -- > 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 > > -- Thanks! Yijing -- 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
