what are the additional features added or removed in AHB lite;
AHB-lite, or "AMBA 3 AHB-lite" to use its more formal name, is a predecessor to "AMBA 5 AHB", or AHB5 as you call it, so the protocol evolution is "AHB-lite" to "AHB5" instead of the direction you asked about.
"AHB5" adds extra functionality and clarifications of a few common functions compared to "AHB-lite", so if you look at the back of the "AHB5" protocol document (Appendix A) you will see a list of changes in the current protocol document compared to the earlier "AHB-lite".
The main changes are additional HPROT bits to signal more memory types, support for security signalling and support for exclusive transfers.
I recently studied the specification of AHB5 (ARM® AMBA® 5 AHB Protocol Specification), I saw the description "In this specification, the term AHB is used to refer to both AHB-Lite and AHB5. Unless stated, signals are common to both AHB-Lite and AHB5." in Chapter 1.2.
So, is that means AHB-lite and AHB5 describe the same thing after the release of AMBA 5?
Definitely not !
A lot of functions are common to the original AHB (AMBA 2 AHB), AHB-lite (AMBA 3 AHB-lite) and AHB5 (AMBA 5 AHB) protocols, so the term "AHB" is used in this AHB5 protocol document when the descriptions apply to both AHB-lite and AHB5.
But where the specification is referring to something specific to AHB5, it will state AHB5.
AHB5 supports everything in AHB-lite, but adds features.
I got it.
Thanks for your explanation!
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