Do you mean x86 linux can map physical address higher than 36-bit for I/O? My understanding is as follows. - Architectural limit of physical address in x86 32-bit mode is 40-bit (depnds on processor version). - The maximum physical address supported by current x86 linux kernel in 32-bit mode is 36-bit. On my environment, physical address higher than 40-bit (ex. 0xfc00001c000) is assigned to some PCI devices. I think there is no way to handle such high physical address in 32-bit mode. Thanks, Kenji Kaneshige
Please ignore above. I misunderstood the architectural limit of physical address in x86 32-bit mode. It is not 40-bits, but 52-bits. Thanks, Kenji Kaneshige -- 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
