+For config space access there are different windows specific access methods:
+- win32-kldbg - Kernel Local Debugging Driver kldbgdrv.sys
+- win32-sysdbg - NT SysDbg interface
+- intel-conf1 - Direct hardware access via Intel configuration mechanism 1
+
+The default access method is win32-cfgmgr32 and by default it tries to use
+one of the above config access access method to provide as much as possible
+information to application. More details about particular access method and
+caveats are described in the pcilib(8) manual page.
+
+The default access method for config space is win32-kldbg. It uses Microsoft's
+Kernel Local Debugging Driver kldbgdrv.sys. This driver is not part of the
+Windows system but is part of the Microsoft WinDbg tool. It is required to
+have kldbgdrv.sys driver installed in the system32 directory or to have
+windbg.exe or kd.exe binary in PATH. kldbgdrv.sys driver has some restrictions.
+Process needs to have Debug privilege and Windows system has to be booted with
+Debugging option. Debugging option can be enabled by calling (takes effect
+after next boot): bcdedit /debug on
+
+Download links for WinDbg 6.12.2.633 standalone installer from Microsoft:
+https://download.microsoft.com/download/A/6/A/A6AC035D-DA3F-4F0C-ADA4-37C8E5D34E3D/setup/WinSDKDebuggingTools_amd64/dbg_amd64.msi
+https://download.microsoft.com/download/A/6/A/A6AC035D-DA3F-4F0C-ADA4-37C8E5D34E3D/setup/WinSDKDebuggingTools/dbg_x86.msi
+
+To access config space via intel-conf1 access method on NT-based systems via
+NT ProcessUserModeIOPL system call, it is required to have SeTcbPrivilege