This discussion has been locked.
You can no longer post new replies to this discussion. If you have a question you can start a new discussion

AXI5 : Untranslated Transactions property for A*MMU* signals and similarly for AXI5-Lite for AWSTASH*

Hi,

I'm trying to add some checks for AXI5 / AXI5 -Lite protocol.

When Untranslated Transaction is TRUE, do all of the signals

A[R/W]MMUSECSID

A[R/W]MMUSID

A[R/W]MMUSSIDV

A[R/W]MMUSSID

A[R/W]MMUATST

need to be defined and used together.

For example, if I didn't have the ARMMUSECSID and AWMMUSECSID defined in the AXI5 protocol would the protocol still work correctly ?

Basically, once Untranslated Transaction is defined to be TRUE , do all of the A*MMU* signals need to be defined together ?

(FALSE) None or (TRUE) ALL signals.

And similarly for AXI5-Lite  AWSTASH* signals.

If Cache_Stash_Transactions is TRUE, do all AWSTASH* signals need to be defined on the AXI5-Lite protocol ?

One cannot leave out one of the signals from the set {AWSTASHID, AWSTASHIDEN, AWSTASHLPID, AWSTASHLPIDEN}.

Thanks,

David

Parents
  • Basically, once Untranslated Transaction is defined to be TRUE , do all of the A*MMU* signals need to be defined together ?

    This is partially described in E2.12.2 and Table F2-2 in the AMBA Specifications.

    In general, the AxMMU* signals are optional if the Untranslated_Transactions property is defined, and not allowed if the property is not defined. The exceptions are:

    "All signals are optional with defined default values, with the restrictions:

    • ARMMUSSID and ARMMUSSIDV must either be both present or both absent.

    • AWMMUSSID and AWMMUSSIDV must either be both present or both absent."

    If Cache_Stash_Transactions is TRUE, do all AWSTASH* signals need to be defined on the AXI5-Lite protocol ?

    Information can be found in E2.2.2.

    "The following rules apply to the AW channel signaling associated with the Cache_Stash_Transactions property:

    • AWSTASHNID and AWSTASHNIDEN must either be both present or both absent.

    • AWSTASHLPID and AWSTASHLPIDEN must either be both present or both absent."

    The AWSTASHNID/AWSTASHNIDEN are expected to be present in most cases, unless there is only one possible target for the stash request.

Reply
  • Basically, once Untranslated Transaction is defined to be TRUE , do all of the A*MMU* signals need to be defined together ?

    This is partially described in E2.12.2 and Table F2-2 in the AMBA Specifications.

    In general, the AxMMU* signals are optional if the Untranslated_Transactions property is defined, and not allowed if the property is not defined. The exceptions are:

    "All signals are optional with defined default values, with the restrictions:

    • ARMMUSSID and ARMMUSSIDV must either be both present or both absent.

    • AWMMUSSID and AWMMUSSIDV must either be both present or both absent."

    If Cache_Stash_Transactions is TRUE, do all AWSTASH* signals need to be defined on the AXI5-Lite protocol ?

    Information can be found in E2.2.2.

    "The following rules apply to the AW channel signaling associated with the Cache_Stash_Transactions property:

    • AWSTASHNID and AWSTASHNIDEN must either be both present or both absent.

    • AWSTASHLPID and AWSTASHLPIDEN must either be both present or both absent."

    The AWSTASHNID/AWSTASHNIDEN are expected to be present in most cases, unless there is only one possible target for the stash request.

Children
No data