Function 21, subfunction 12 - enable/disable low-level access to PCI.
Parameters:
- eax = 21 - function number
- ebx = 12 - subfunction number
- ecx = 0/1 - disable/enable
Returned value:
Remarks:
- Is used in operations with PCI bus (function 62).
- The current implementation uses only low bit of ecx.
- To get current status use subfunction 12 of function 26.