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Reading PCI configuration space and modifying from storport

Sony_PappanSony_Pappan Member Posts: 3

I would like to change the relaxed ordering bit in PCI capabilty register/Device control register from stoport.
I could see storport have StorportGetBusdata function, but could not see a way to read and modify the PCI capability regisister.
As StorportGetBusdata just donot allow to read the PCI config space with some specific offset.
Is there any other API availble in Storport to read and modicy PCI config space?


  • Tim_RobertsTim_Roberts Member - All Emails Posts: 13,627

    What are you hoping to accomplish here? If the device is capable of handling relaxed ordering, it sets the bit. If the operating system decides it can't be supported, it clears the bit. You aren't really in a position to override either one.

    Tim Roberts, [email protected]
    Providenza & Boekelheide, Inc.

  • Sony_PappanSony_Pappan Member Posts: 3

    Hi Tim Roberts
    Here the OS side there is a data corruption because I doubt this is due to Relaxed ordeing bit set. Would like to disable it in the OS Storport miniport driver and see the corruption happening or not.

  • Mark_RoddyMark_Roddy Member - All Emails Posts: 4,374
    via Email
    Use StorPortSetBusDataByOffset for setting. Unlikely to be your problem

    Mark Roddy
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