x86 system address

How is the I/O Address Space mapped to devices? https://stackoverflow.com/questions/9222251/how-is-the-i-o-address-space-
mapped-to-devices
System Address Map Initialization in x86/x64 Architecture https://resources.infosecinstitute.com/system-address-map-
initialization-in-x86x64-architecture-part-1-pci-based-systems/ https://resources.infosecinstitute.com/system-address-map-
initialization-x86x64-architecture-part-2-pci-express-based-systems/
Memory Management - x86 Virtual Address Space https://techcommunity.microsoft.com/t5/Ask-The-Performance-Team/Memory-
Management-x86-Virtual-Address-Space/ba-p/372536
Are the configuration space registers mapped to memory space or IO space? https://stackoverflow.com/questions/44462738/are-
the-configuration-space-registers-mapped-to-memory-space-or-io-space