@@ -30,6 +30,35 @@ definitions:
+  -
+    name: phy-test-pattern
+    enum-name: phy-test-pattern
+    type: enum
+    name-prefix: phy-test-pattern-
+    doc: PRBS and other PHY test patterns
+    entries:
+      - off
+      - prbs7
+      - prbs9
+      - prbs11
+      - prbs13
+      - prbs15
+      - prbs23
+      - prbs31
+      - ssprq
+      - prbs13q
+      - prbs31q
+      - square8

+    name: phy-test-action
+    enum-name: phy-test-action
+    type: enum
+    name-prefix: phy-test-action-
+    doc: Actions for PHY BERT test control
+    entries:
+      - none
+      - start
+      - stop

+    name: phy-test
+    attr-cnt-name: __ethtool-a-phy-test-cnt
+    doc: |
+      PHY test configuration for pattern generation/checking,
+      BERT (Bit Error Rate Test), and statistics.
+    attributes:
+      -
+        name: unspec
+        type: unused
+        value: 0
+      -
+        name: header
+        type: nest
+        nested-attributes: header
+      -
+        name: lane
+        type: u32
+        doc: PHY lane index to target for the test operation
+      -
+        name: tx-pattern
+        type: u32
+        doc: TX test pattern type (PRBS or square8 wave)
+        enum: phy-test-pattern
+      -
+        name: rx-pattern
+        type: u32
+        doc: RX checker pattern type (PRBS or square8 wave)
+        enum: phy-test-pattern
+      -
+        name: bert-action
+        type: u32
+        doc: BERT test start/stop
+        enum: phy-test-action
+      -
+        name: inject-error-count
+        type: u32
+        doc: |
+          Inject a specified number of bit errors into the PHY transmit data
+          stream for diagnostic verification purposes.
+
+          Context and Purpose:
+            When performing Bit Error Ratio Testing (BERT), the receiving side
+            runs a PRBS checker that monitors for bit errors. Before relying
+            on a zero-error BERT result, operators need to confirm Checker
+            state and configuration to qualify result as TRUE.
+            A checker that is broken or misconfigured would also report
+            zero errors, giving a FALSE pass. Error injection provides this
+            confirmation by deliberately introducing a known number of errors
+            on the transmit side and verifying they appear on the receive side.
+
+            Note:
+            Receiver under test maybe in the same port as the transmitter
+            (loopback mode) or a different port in the same device or another
+            device connected to the transmitting port (non-loopback mode).
+
+          Layer and Mechanism:
+            Error injection operates at the PMA/PMD boundary. This is
+            bit-level injection in the serial data stream, not frame-level.
+            The SerDes Built-In Self Test (BIST) block inverts the specified
+            number of bits in the outgoing serial stream. The injection does
+            not distinguish between data frames and test patterns; it
+            corrupts raw bits at the physical layer regardless of what the
+            stream carries.
+
+          Mode of Operation:
+            This command implements "one-shot" injection: a single burst of
+            N bit errors injected immediately. The PHY inverts exactly N
+            consecutive bits in the serial transmit stream at the PMA/PMD
+            layer, then resumes clean transmission. No continuous/fixed-rate
+            injection mode is provided.
+
+          Prerequisites:
+            - A PRBS test pattern must be active on the transmitting port
+              (tx-pattern != off).
+            - The receiving port must have the matching rx-pattern configured
+              and ber-lock-status must be "locked" (indicating the checker
+              has synchronized to the incoming pattern).
+            - BERT must be running on the receiving port (bert start issued).
+
+              Note:
+              Availability of BIST mode test pattern generator, checker and
+              lock indication is IP dependent.
+
+          Semantics:
+            - Fire-and-forget: the command completes immediately. No
+              persistent state is created. Each invocation is an independent
+              injection event.
+            - The command may be issued multiple times. Each invocation
+              injects an additional burst of errors (counts accumulate on
+              the receiver's ber-error-count across invocations).
+            - If no test pattern is active, the behaviour is
+              implementation-defined (hardware may silently ignore the
+              request or return an error).
+
+          Expected Outcome:
+            After injecting N errors on the TX port, the far-end receiver's
+            ber-error-count (read via --show-phy-test) should increment by
+            exactly N (within hardware counter precision). This confirms:
+              1. The PRBS checker is locked and actively counting errors.
+              2. The data path between TX and RX is intact.
+              3. The BERT counters are functioning correctly.
+
+          Example Workflow:
+            # Configure TX pattern on port A
+            ethtool --phy-test eth1 lane 0 tx-pattern prbs31
+            # Configure RX checker on port B, start BERT
+            ethtool --phy-test eth2 lane 0 rx-pattern prbs31
+            ethtool --phy-test eth2 lane 0 bert start
+            # Verify lock
+            ethtool --show-phy-test eth2 lane 0
+            #   -> ber-lock-status: locked, ber-error-count: 0
+            # Inject 5 errors from TX side
+            ethtool --phy-test eth1 lane 0 inject-errors 5
+            # Confirm errors were detected
+            ethtool --show-phy-test eth2 lane 0
+            #   -> ber-error-count: 5
+      -
+        name: ber-lock-status
+        type: u8
+        doc: PRBS lock status (1=locked, 0=not locked)
+      -
+        name: ber-error-count
+        type: u64
+        doc: BERT bit error count
+      -
+        name: ber-total-bits-sent
+        type: u64
+        doc: BERT total bits sent
+      -
+        name: supported-test-patterns
+        type: u32
+        doc: Bitmask of supported test patterns
 
+    -
+      name: phy-test-act
+      doc: |
+        Configure PHY test parameters. Each attribute is optional and only
+        specified attributes are applied. TX/RX patterns are set on the
+        local port. BERT and error injection operate on the receiver port.
+        Typical workflow:
+          ethtool --phy-test eth1 lane 0 tx-pattern prbs7   (TX side)
+          ethtool --phy-test eth2 lane 0 rx-pattern prbs7   (RX side)
+          ethtool --phy-test eth2 lane 0 bert start         (start BERT on RX)
+          ethtool --phy-test eth1 lane 0 inject-errors 10   (inject 10 errors on TX)
+          ethtool --show-phy-test eth2 lane 0               (read counters, expect +10)
+          ethtool --phy-test eth2 lane 0 bert stop          (stop BERT)
+
+      attribute-set: phy-test
+
+      do:
+        request:
+          attributes:
+            - header
+            - lane
+            - tx-pattern
+            - rx-pattern
+            - bert-action
+            - inject-error-count
+    -
+      name: phy-test-get
+      doc: |
+        Get PHY test configuration status, supported patterns, and BERT
+        statistics (lock status, error count, total bits).
+
+      attribute-set: phy-test
+
+      do:
+        request:
+          attributes:
+            - header
+            - lane
+        reply:
+          attributes:
+            - header
+            - lane
+            - tx-pattern
+            - rx-pattern
+            - supported-test-patterns
+            - ber-lock-status
+            - ber-error-count
+            - ber-total-bits-sent
 
 mcast-groups:
   list:

- Shubham D