module ieee802-dot1q-preemption {
  namespace urn:ieee:std:802.1Q:yang:ieee802-dot1q-preemption;
  prefix preempt;
  import ieee802-dot1q-types {
    prefix dot1q-types;
  }
  import ietf-interfaces {
    prefix if;
  }
  import ieee802-dot1q-bridge {
    prefix dot1q;
  }
  organization
    "IEEE 802.1 Working Group";
  contact
    "WG-URL: http://www.ieee802.org/1/
    WG-EMail: stds-802-1-L@ieee.org
    
    Contact: IEEE 802.1 Working Group Chair
    Postal: C/O IEEE 802.1 Working Group
    IEEE Standards Association
    445 Hoes Lane
    P.O. Box 1331
    Piscataway
    NJ 08855-1331
    USA
    
    E-mail: STDS-802-1-L@IEEE.ORG";
  description
    "This module provides for management of IEEE Std 802.1Q Bridges
    that support Frame Preemption.";

  revision 2020-07-07 {
    description
      "Published as part of IEEE Std 802.1Qcw.
      Initial version.";
    reference
      "IEEE Std 802.1Qcw - Bridges and Bridged Networks — Amendment: 
      YANG Data Models for Scheduled Traffic, Frame Preemption, and 
      Per-Stream Filtering and Policing.";
  }

  feature frame-preemption {
    description
      "Frame preemption supported.";
    reference
      "IEEE Std 802.1Q-2018";
  }
  augment "/if:interfaces/if:interface/dot1q:bridge-port" {
    if-feature "frame-preemption";
    description
      "Augment bridge-port with Frame Preemption configuration.";
    container frame-preemption-parameters {
      description
        "A table containing a set of frame preemption parameters, one
        for each Port. All writeable objects in this table must be
        persistent over power up restart/reboot.";
      reference
        "12.30.1 of IEEE Std 802.1Q-2018";
      list frame-preemption-status-table {
        key "priority";
        description
          "The framePreemptionStatusTable consists of 8
          framePreemptionAdminStatus values, one per priority";
        reference
          "12.30.1.1 of IEEE Std 802.1Q-2018";
        leaf priority {
          type dot1q-types:priority-type;
          description
            "Priority.";
        }
        leaf frame-preemption-status {
          type enumeration {
            enum express {
              description
                "Frames queued for the priority are to be transmitted
                using the express service for the Port.";
            }
            enum preemptible {
              description 
                "Frames queued for the priority are to be transmitted
                using the preemptible service for the Port and
                preemption is enabled for the Port.";
            }
          }
          default "express";
          description
            "The value of the framePreemptionAdminStatus parameter for
            the traffic class. The default value of the
            framePreemptionAdminStatus parameter is express. The
            value of this object must be retained across
            reinitializations of the management system.";
          reference
            "12.30.1.1.1 of IEEE Std 802.1Q-2018";
        }
      }
      leaf hold-advance {
        type uint32;
        units "nanoseconds";
        config false;
        description
          "The value of the holdAdvance parameter for the Port in
          nanoseconds. There is no default value; the holdAdvance is a
          property of the underlying MAC.";
        reference
          "12.30.1.2 of IEEE Std 802.1Q-2018";
      }
      leaf release-advance {
        type uint32;
        units "nanoseconds";
        config false;
        description
          "The value of the releaseAdvance parameter for the Port in
          nanoseconds. There is no default value; the releaseAdvance
          is a property of the underlying MAC.";
        reference
          "12.30.1.3 of IEEE Std 802.1Q-2018";
      }
      leaf preemption-active {
        type boolean;
        config false;
        description
          "TRUE if preemption is both supported by the MAC and
          currently active.";
        reference
          "12.30.1.4 of IEEE Std 802.1Q-2018";
      }
      leaf hold-request {
        type enumeration {
          enum hold {
            value 1;
            description
              "A hold request has been issued to the MAC.";
          }
          enum release {
            value 2;
            description
              "A release request has been issued to the MAC.";
          }
        }
        config false;
        description
          "The value of the holdRequest parameter for the Port, either 
          hold (1) or release (2). The value of this object is release 
          (2) on system initialization.";
        reference
          "12.30.1.5 of IEEE Std 802.1Q-2018";
      }
    }
  }
}