[T10] [SAS] Clarification on how to handle "Enable APTA request" from Link Layer to Phy layer

Lana Chan lana at cadence.com
Wed May 15 16:03:42 PDT 2019


Hello SAS Experts
Can you please help clarify "Enable APTA request" handling from the link layer to the Phy layer:

Specification reference(SPLv13):
==========================

  1.  As per section 6.18.4.2 SL_CC0:Idle state and 6.18.4.2.1 State description


This state is the initial state and is the state that is used while there is no connection pending or established.

Upon entry into this state, this state shall:
h) send an Enable APTA request to the phy layer.




  1.  As per section 3.7.2 Transitions

Upon entry into a state, all actions to be processed in that state are processed. If a state is re-entered from itself, then all actions to be processed in the state are processed again.



Question :
========

  1.  Is the Link layer required to send "an Enable APTA request to the phy layer" at every clock/time (continuously) where it is still there in SL_CC0 state in case of No connection request (if it is considered to re-entered from itself)

OR


  1.  Is Link layer required to send "an Enable APTA request to the phy layer" only at one time as it is entered in SL_CC0 state ?
     *   If this is the case, then PAPTA_A_L0_IDLE to PAPTA_A_L1_WAIT_FOR_START state transition happens only time before SL_CC0 to SL_CCn state transition (n= any valid state as per spec)
     *   As this state transition has indirect dependency on "Enable APTA request" from Link layer.

Please let us know your thought on this.

Kind Regards
Lana



-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://www.t10.org/pipermail/t10/attachments/20190515/168db1b3/attachment.html>


More information about the T10 mailing list