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The information that may help you is stated in sections 10.1.26 and 12.1.56, on pages 1339 and 1400 of the Apollo Lake SoC External Design Specification (EDS) Volume 2 of 4 document # 557556; and in section 4.5, on pages 42 and 43 of the
Apollo Lake SoC External Design Specification (EDS) Volume 4 of 4 document # 559360.
Also, you must review with the assistance of your BIOS vendor the information stated in sections 15.1.3, 15.5.3, and 16.3.1, on pages from 163 to 171, 175, 176, 177, and 178 of the Apollo Lake Platform Intel Architecture Firmware Specification (Volume 2 of 2) BIOS Specification document # 559811.
We hope that this information is useful to you.