DMIBAR

[karimmokhlis]

I found something called DMIBAR. Is it a register in Intel systems that stores the base address for output on the DMI path to reach the chipset? For example, if I want to access the USB, does the BIOS need to set the DMIBAR register with the base address so that the processor, if the address is within range, can send the request over that bus? Is what I'm saying correct?

[DeancR_Intel]

Hi karimmokhlis,

Thank you for reaching out with your question about DMIBAR. I appreciate your interest in understanding how Intel systems operate, and I'm here to assist you with your inquiry.

DMIBAR, or DMI Base Address Register, is indeed a register used in Intel systems. It stores the base address for the Direct Media Interface (DMI) path, which connects the processor to the chipset. Your understanding is correct in that the BIOS sets the DMIBAR register with the base address, allowing the processor to communicate with devices like USB if the address falls within the specified range.

To provide more specific guidance, could you please share some additional information about your system? If you're comfortable doing so, you can use the Intel System Support Utility (SSU) to gather this information. You can download the SSU from the following link: Intel System Support Utility. Alternatively, please provide the following details:

1. Motherboard Model:
2. CPU Model:

Your cooperation is greatly appreciated, and I am committed to providing you with the information you need. If you have any questions or need further assistance, please feel free to reach out.

Thank you for your understanding and support.

Best regards, 

Dean R. 

Intel Customer Support Technician 

[karimmokhlis]

For example, if the BIOS sets the DMIBAR to 0xc00000000, does that mean the BIOS must assign addresses for the devices connected to the chipset starting from that address 0xc00000000? So that when the processor sees an address, it compares it with the DMIBAR address and redirects it directly to the chipset? Like, for instance, if it sees 0xc100000000, it would send it over the DMI right away?

[DeancR_Intel]

Hi karimmokhlis,

I wanted to follow up on the previous message regarding your inquiry. Have you had a chance to review it? If you have any questions or need further information, please let me know.

Best regards, 

Dean R. 

Intel Customer Support Technician 

[DeancR_Intel · Accepted solution]

Hi karimmokhlis,

As you have been unresponsive, I will proceed to close this thread. If you wish to continue the discussion or need further assistance, please feel free to create a new thread. This will help us provide focused support and ensure your concerns are addressed effectively. 

Best regards, 

Dean R. 

Intel Customer Support Technician