Hello. I was wondering whether the IPF documentation has been updated for recent Itanium processors. The latest I seem to find is some 2006 revision! Now in particular I just so happen to notice that Volume 2 (System Architecture) mentions that the VHPT Walker is optional.
Now I have been trying to search this forum for a while and couldn't find a single thread on this one. Is the VHPT walker still "optional"? And if so, what model(s) of the IPF do not have the VHPT Walker?
I am developing an OS and I would like to know this because it would save me a lot of time and effort using the built-in VHPT walker rather than ending up writing slow and buggy code to walk the VHPT - the more hardware I can use the better.
NOTE: So far I don't have any VHPT walking code - I am going to do this if it is actually worth doing.
And it really does puzzle me why such a significant optimization could be made optional in processors!
Let me know if I am "reading things"
Now I am not entirely sure how "on-topic" this is, but it is hard to find the appropriate Itanium resources (other than the Software Developer's Manuals) - such as the Itanium Assembler user's guides, an updated version of the Itanium Assembler (the last I found was the source which was made in 2002), the IA-64 Assembly Assistant, and several other things. I did eventually find the IA-64 Assembler guide but not the other two.
Of course, the guide is also a little out of date, dating back to around the Year 2000! So this means that the new format may not be accompanied for (Itanium has evolved a lot since 2000!)
Now also about the VHPT: does each core share one VHPT walker? Or does each core get a completely separate set of resources (including cache)?