Intel G870 CM8062307260115 User Manual

Datasheet, Volume 1

37

The following features are not supported by the processor with Intel VT-d:

• No support for PCISIG endpoint caching (ATS)
• No support for interrupt remapping
• No support for queue-based invalidation interface
• No support for Intel VT-d read prefetching/snarfing; that is, translations within a 

cacheline are not stored in an internal buffer for reuse for subsequent translations.

• No support for advance fault reporting
• No support for super pages
• No support for 1 or 2 level page walks for isoch remap engine and 1, 2, or 3 level 

walks for non-isoch remap engine

• No support for Intel VT-d translation bypass address range (such usage models 

need to be resolved with VMM help in setting up the page tables correctly)

Intel Trusted Execution Technology (Intel TXT) defines platform-level enhancements 
that provide the building blocks for creating trusted platforms. 

The Intel TXT platform helps to provide the authenticity of the controlling environment 
such that those wishing to rely on the platform can make an appropriate trust decision. 
The Intel TXT platform determines the identity of the controlling environment by 
accurately measuring and verifying the controlling software.

Another aspect of the trust decision is the ability of the platform to resist attempts to 
change the controlling environment. The Intel TXT platform will resist attempts by 
software processes to change the controlling environment or bypass the bounds set by 
the controlling environment.

Intel TXT is a set of extensions designed to provide a measured and controlled launch 
of system software that will then establish a protected environment for itself and any 
additional software that it may execute.

These extensions enhance two areas:

• The launching of the Measured Launched Environment (MLE).
• The protection of the MLE from potential corruption.

The enhanced platform provides these launch and control interfaces using Safer Mode 
Extensions (SMX).

The SMX interface includes the following functions:

• Measured/Verified launch of the MLE.
• Mechanisms to ensure the above measurement is protected and stored in a secure 

location.

• Protection mechanisms that allow the MLE to control attempts to modify itself.