1 Reply Latest reply on Sep 14, 2015 12:00 AM by Cesar Badilla

    Accessing PCI Device IDs by using Software in Protected Mode

    FBDIMM

      Ahoy and welcome brothers.

       

      Currently i am searching for a way to access the PCI Devices of my System by using the DIDs (MSI X58 Pro-E, Intel Xeon E5620)

      I want to Access the Device Number 2, Function 2 @ Bus 0xFF

       

      My goal is to modify the QPI Link Data Rate without using the BIOS but unfortunately the registers are write protected

       

       

      [img]http://extreme.pcgameshardware.de/attachments/846001d1440412820-werte-pci-devices-anpassen-wie-mit-offset-umgehen-c1.png[/img]

       

      I want to replace the conent of this register of QPI Link 1 by the red marked numbers but unfortunately there is some kind of write protection even if they are signed as "RW"

      Is there any Lock Bit that prevents any updating of the QPI Link registers?

       

      [img]http://extreme.pcgameshardware.de/attachments/846002d1440412820-werte-pci-devices-anpassen-wie-mit-offset-umgehen-unters…[/img]

       

      Well.. disabling the MC_Channel Lock Bit Registers also didnt work