[PATCH net-next v4 0/2] dpll: rework fractional frequency offset reporting

[PATCH net-next v4 0/2] dpll: rework fractional frequency offset reporting

[Ivan Vecera]

Rework how the fractional frequency offset (FFO) is reported in
the DPLL subsystem.

Both fractional-frequency-offset (PPM) and
fractional-frequency-offset-ppt (PPT) attributes are now present at
the top level of a pin and inside each pin-parent-device nest. They
carry the same measurement at different precisions.

Introduce enum dpll_ffo_type and struct dpll_ffo_param to distinguish
FFO contexts: DPLL_FFO_PORT_RXTX_RATE for the RX vs TX symbol rate
offset at the top level, and DPLL_FFO_PIN_DEVICE for the pin vs
parent DPLL offset in the nest. Drivers declare which types they
support via the supported_ffo bitmask in dpll_pin_ops; the core only
calls ffo_get for opted-in types.

Patch 1 adds the type-safe FFO API, updates the YAML spec, netlink
handling, and documentation, and converts mlx5 and zl3073x drivers.

Patch 2 implements the nested FFO for zl3073x using the
dpll_df_offset_x register with ref_ofst=1, providing 2^-48
resolution. The old per-reference frequency measurement is removed
as it was redundant with measured-frequency.

Changes v3 -> v4:
- Replace dpll=NULL overloading with enum dpll_ffo_type and
  struct dpll_ffo_param (Jakub Kicinski)
- Add supported_ffo opt-in bitmask in dpll_pin_ops for fail-close
  driver validation (Jakub Kicinski)
- Add WARN_ON in dpll_pin_register for supported_ffo without
  ffo_get callback
- Use atomic64_t for freq_offset to prevent torn reads on 32-bit

Changes v2 -> v3:
- Keep both FFO attributes (PPM and PPT) at both levels instead of
  moving PPT under pin-parent-device only (Jiri Pirko)
- Unify attribute documentation to describe semantics at each level

Changes v1 -> v2:
- Minor commit message fixes

Ivan Vecera (2):
  dpll: add fractional frequency offset to pin-parent-device
  dpll: zl3073x: report FFO as DPLL vs input reference offset

 Documentation/driver-api/dpll.rst             | 20 +++++++++
 Documentation/netlink/specs/dpll.yaml         | 28 +++++++-----
 drivers/dpll/dpll_core.c                      |  3 +-
 drivers/dpll/dpll_netlink.c                   | 30 +++++++------
 drivers/dpll/dpll_nl.c                        |  2 +
 drivers/dpll/zl3073x/chan.c                   | 31 ++++++++++++-
 drivers/dpll/zl3073x/chan.h                   | 14 ++++++
 drivers/dpll/zl3073x/core.c                   | 45 -------------------
 drivers/dpll/zl3073x/dpll.c                   | 40 ++++++++---------
 drivers/dpll/zl3073x/ref.h                    | 14 ------
 drivers/dpll/zl3073x/regs.h                   | 15 +++++++
 .../net/ethernet/mellanox/mlx5/core/dpll.c    |  6 ++-
 include/linux/dpll.h                          | 16 ++++++-
 13 files changed, 154 insertions(+), 110 deletions(-)

-- 
2.53.0

[PATCH net-next v4 1/2] dpll: add fractional frequency offset to pin-parent-device

[Ivan Vecera]

Add both fractional-frequency-offset (PPM) and
fractional-frequency-offset-ppt (PPT) attributes to the
pin-parent-device nested attribute set, alongside the existing
top-level pin attributes. Both carry the same measurement at
different precisions.

Introduce enum dpll_ffo_type and struct dpll_ffo_param to
distinguish FFO contexts: DPLL_FFO_PORT_RXTX_RATE for the RX vs
TX symbol rate offset reported at the top level, and
DPLL_FFO_PIN_DEVICE for the pin vs parent DPLL offset reported
in the pin-parent-device nest.

Add a supported_ffo bitmask to struct dpll_pin_ops so drivers
declare which FFO types they support. The core only calls ffo_get
for types the driver has opted into, eliminating the need for
per-driver NULL pointer guards. Validate at pin registration time
that supported_ffo is not set without an ffo_get callback.

Update mlx5 (DPLL_FFO_PORT_RXTX_RATE) and zl3073x
(DPLL_FFO_PORT_RXTX_RATE) drivers to use the new API.

Add documentation for both FFO types to dpll.rst.

Changes v3 -> v4:
- Replace dpll=NULL overloading with enum dpll_ffo_type and
  struct dpll_ffo_param (Jakub Kicinski)
- Add supported_ffo opt-in bitmask in dpll_pin_ops for fail-close
  driver validation (Jakub Kicinski)
- Add WARN_ON in dpll_pin_register for supported_ffo without
  ffo_get callback

Reviewed-by: Jiri Pirko <jiri@nvidia.com>
Signed-off-by: Ivan Vecera <ivecera@redhat.com>
---
 Documentation/driver-api/dpll.rst             | 20 +++++++++++++
 Documentation/netlink/specs/dpll.yaml         | 28 ++++++++++-------
 drivers/dpll/dpll_core.c                      |  3 +-
 drivers/dpll/dpll_netlink.c                   | 30 ++++++++++---------
 drivers/dpll/dpll_nl.c                        |  2 ++
 drivers/dpll/zl3073x/dpll.c                   |  6 ++--
 .../net/ethernet/mellanox/mlx5/core/dpll.c    |  6 ++--
 include/linux/dpll.h                          | 16 +++++++++-
 8 files changed, 81 insertions(+), 30 deletions(-)

diff --git a/Documentation/driver-api/dpll.rst b/Documentation/driver-api/dpll.rst
index 37eaef785e304..090cd4d017c3a 100644
--- a/Documentation/driver-api/dpll.rst
+++ b/Documentation/driver-api/dpll.rst
@@ -258,6 +258,26 @@ in the ``DPLL_A_PIN_PHASE_OFFSET`` attribute.
   ``DPLL_A_PHASE_OFFSET_MONITOR`` attr state of a feature
   =============================== ========================
 
+Fractional frequency offset
+===========================
+
+The fractional frequency offset (FFO) is reported through two attributes
+that carry the same measurement at different precisions:
+
+- ``DPLL_A_PIN_FRACTIONAL_FREQUENCY_OFFSET`` in PPM (parts per million)
+- ``DPLL_A_PIN_FRACTIONAL_FREQUENCY_OFFSET_PPT`` in PPT (parts per trillion)
+
+Both attributes appear at the top level of a pin and inside each
+``pin-parent-device`` nest. Two FFO types are defined:
+
+- ``DPLL_FFO_PORT_RXTX_RATE`` - RX vs TX symbol rate offset (top-level)
+- ``DPLL_FFO_PIN_DEVICE`` - pin vs parent DPLL offset (per-parent)
+
+The driver declares which types it supports via the ``supported_ffo``
+bitmask in ``struct dpll_pin_ops``. The core only calls the ``ffo_get``
+callback for types the driver has opted into. The requested type is
+passed to the driver in the ``struct dpll_ffo_param``.
+
 Frequency monitor
 =================
 
diff --git a/Documentation/netlink/specs/dpll.yaml b/Documentation/netlink/specs/dpll.yaml
index c45de70a47ce6..91a172617b3a9 100644
--- a/Documentation/netlink/specs/dpll.yaml
+++ b/Documentation/netlink/specs/dpll.yaml
@@ -448,12 +448,14 @@ attribute-sets:
         name: fractional-frequency-offset
         type: sint
         doc: |
-          The FFO (Fractional Frequency Offset) between the RX and TX
-          symbol rate on the media associated with the pin:
-          (rx_frequency-tx_frequency)/rx_frequency
+          The FFO (Fractional Frequency Offset) of the pin.
+          At top level this represents the RX vs TX symbol rate
+          offset on the media associated with the pin. Inside
+          the pin-parent-device nest it represents the frequency
+          offset between the pin and its parent DPLL device.
           Value is in PPM (parts per million).
-          This may be implemented for example for pin of type
-          PIN_TYPE_SYNCE_ETH_PORT.
+          This is a lower-precision version of
+          fractional-frequency-offset-ppt.
       -
         name: esync-frequency
         type: u64
@@ -492,12 +494,14 @@ attribute-sets:
         name: fractional-frequency-offset-ppt
         type: sint
         doc: |
-          The FFO (Fractional Frequency Offset) of the pin with respect to
-          the nominal frequency.
-          Value = (frequency_measured - frequency_nominal) / frequency_nominal
+          The FFO (Fractional Frequency Offset) of the pin.
+          At top level this represents the RX vs TX symbol rate
+          offset on the media associated with the pin. Inside
+          the pin-parent-device nest it represents the frequency
+          offset between the pin and its parent DPLL device.
           Value is in PPT (parts per trillion, 10^-12).
-          Note: This attribute provides higher resolution than the standard
-          fractional-frequency-offset (which is in PPM).
+          This is a higher-precision version of
+          fractional-frequency-offset.
       -
         name: measured-frequency
         type: u64
@@ -534,6 +538,10 @@ attribute-sets:
         name: operstate
       -
         name: phase-offset
+      -
+        name: fractional-frequency-offset
+      -
+        name: fractional-frequency-offset-ppt
   -
     name: pin-parent-pin
     subset-of: pin
diff --git a/drivers/dpll/dpll_core.c b/drivers/dpll/dpll_core.c
index cbb635db43210..20a54728549cc 100644
--- a/drivers/dpll/dpll_core.c
+++ b/drivers/dpll/dpll_core.c
@@ -879,7 +879,8 @@ dpll_pin_register(struct dpll_device *dpll, struct dpll_pin *pin,
 	    WARN_ON(!ops->direction_get) ||
 	    WARN_ON(ops->measured_freq_get &&
 		    (!dpll_device_ops(dpll)->freq_monitor_get ||
-		     !dpll_device_ops(dpll)->freq_monitor_set)))
+		     !dpll_device_ops(dpll)->freq_monitor_set)) ||
+	    WARN_ON(ops->supported_ffo && !ops->ffo_get))
 		return -EINVAL;
 
 	mutex_lock(&dpll_lock);
diff --git a/drivers/dpll/dpll_netlink.c b/drivers/dpll/dpll_netlink.c
index 05cf946b4be5e..00e8696cb267b 100644
--- a/drivers/dpll/dpll_netlink.c
+++ b/drivers/dpll/dpll_netlink.c
@@ -417,31 +417,28 @@ dpll_msg_add_phase_offset(struct sk_buff *msg, struct dpll_pin *pin,
 
 static int dpll_msg_add_ffo(struct sk_buff *msg, struct dpll_pin *pin,
 			    struct dpll_pin_ref *ref,
+			    enum dpll_ffo_type type,
 			    struct netlink_ext_ack *extack)
 {
 	const struct dpll_pin_ops *ops = dpll_pin_ops(ref);
-	struct dpll_device *dpll = ref->dpll;
-	s64 ffo;
+	struct dpll_ffo_param ffo = { .type = type };
 	int ret;
 
-	if (!ops->ffo_get)
+	if (!ops->ffo_get || !(ops->supported_ffo & BIT(type)))
 		return 0;
-	ret = ops->ffo_get(pin, dpll_pin_on_dpll_priv(dpll, pin),
-			   dpll, dpll_priv(dpll), &ffo, extack);
+	ret = ops->ffo_get(pin, dpll_pin_on_dpll_priv(ref->dpll, pin),
+			   ref->dpll, dpll_priv(ref->dpll), &ffo, extack);
 	if (ret) {
 		if (ret == -ENODATA)
 			return 0;
 		return ret;
 	}
-	/* Put the FFO value in PPM to preserve compatibility with older
-	 * programs.
-	 */
-	ret = nla_put_sint(msg, DPLL_A_PIN_FRACTIONAL_FREQUENCY_OFFSET,
-			   div_s64(ffo, 1000000));
-	if (ret)
+	if (nla_put_sint(msg, DPLL_A_PIN_FRACTIONAL_FREQUENCY_OFFSET,
+			 div_s64(ffo.ffo, 1000000)))
 		return -EMSGSIZE;
-	return nla_put_sint(msg, DPLL_A_PIN_FRACTIONAL_FREQUENCY_OFFSET_PPT,
-			    ffo);
+	return nla_put_sint(msg,
+			    DPLL_A_PIN_FRACTIONAL_FREQUENCY_OFFSET_PPT,
+			    ffo.ffo);
 }
 
 static int dpll_msg_add_measured_freq(struct sk_buff *msg, struct dpll_pin *pin,
@@ -686,6 +683,10 @@ dpll_msg_add_pin_dplls(struct sk_buff *msg, struct dpll_pin *pin,
 		if (ret)
 			goto nest_cancel;
 		ret = dpll_msg_add_phase_offset(msg, pin, ref, extack);
+		if (ret)
+			goto nest_cancel;
+		ret = dpll_msg_add_ffo(msg, pin, ref,
+				       DPLL_FFO_PIN_DEVICE, extack);
 		if (ret)
 			goto nest_cancel;
 		nla_nest_end(msg, attr);
@@ -748,7 +749,8 @@ dpll_cmd_pin_get_one(struct sk_buff *msg, struct dpll_pin *pin,
 	ret = dpll_msg_add_pin_phase_adjust(msg, pin, ref, extack);
 	if (ret)
 		return ret;
-	ret = dpll_msg_add_ffo(msg, pin, ref, extack);
+	ret = dpll_msg_add_ffo(msg, pin, ref,
+			       DPLL_FFO_PORT_RXTX_RATE, extack);
 	if (ret)
 		return ret;
 	ret = dpll_msg_add_measured_freq(msg, pin, ref, extack);
diff --git a/drivers/dpll/dpll_nl.c b/drivers/dpll/dpll_nl.c
index 58235845fa3d5..b1d9182c7802f 100644
--- a/drivers/dpll/dpll_nl.c
+++ b/drivers/dpll/dpll_nl.c
@@ -19,6 +19,8 @@ const struct nla_policy dpll_pin_parent_device_nl_policy[DPLL_A_PIN_OPERSTATE +
 	[DPLL_A_PIN_STATE] = NLA_POLICY_RANGE(NLA_U32, 1, 3),
 	[DPLL_A_PIN_OPERSTATE] = NLA_POLICY_RANGE(NLA_U32, 1, 4),
 	[DPLL_A_PIN_PHASE_OFFSET] = { .type = NLA_S64, },
+	[DPLL_A_PIN_FRACTIONAL_FREQUENCY_OFFSET] = { .type = NLA_SINT, },
+	[DPLL_A_PIN_FRACTIONAL_FREQUENCY_OFFSET_PPT] = { .type = NLA_SINT, },
 };
 
 const struct nla_policy dpll_pin_parent_pin_nl_policy[DPLL_A_PIN_STATE + 1] = {
diff --git a/drivers/dpll/zl3073x/dpll.c b/drivers/dpll/zl3073x/dpll.c
index 6fd718696de0d..05e63661bf074 100644
--- a/drivers/dpll/zl3073x/dpll.c
+++ b/drivers/dpll/zl3073x/dpll.c
@@ -295,11 +295,12 @@ zl3073x_dpll_input_pin_ref_sync_set(const struct dpll_pin *dpll_pin,
 static int
 zl3073x_dpll_input_pin_ffo_get(const struct dpll_pin *dpll_pin, void *pin_priv,
 			       const struct dpll_device *dpll, void *dpll_priv,
-			       s64 *ffo, struct netlink_ext_ack *extack)
+			       struct dpll_ffo_param *ffo,
+			       struct netlink_ext_ack *extack)
 {
 	struct zl3073x_dpll_pin *pin = pin_priv;
 
-	*ffo = pin->freq_offset;
+	ffo->ffo = pin->freq_offset;
 
 	return 0;
 }
@@ -1274,6 +1275,7 @@ zl3073x_dpll_freq_monitor_set(const struct dpll_device *dpll,
 }
 
 static const struct dpll_pin_ops zl3073x_dpll_input_pin_ops = {
+	.supported_ffo = BIT(DPLL_FFO_PORT_RXTX_RATE),
 	.direction_get = zl3073x_dpll_pin_direction_get,
 	.esync_get = zl3073x_dpll_input_pin_esync_get,
 	.esync_set = zl3073x_dpll_input_pin_esync_set,
diff --git a/drivers/net/ethernet/mellanox/mlx5/core/dpll.c b/drivers/net/ethernet/mellanox/mlx5/core/dpll.c
index bce72e8d1bc31..7c69d9029bfa4 100644
--- a/drivers/net/ethernet/mellanox/mlx5/core/dpll.c
+++ b/drivers/net/ethernet/mellanox/mlx5/core/dpll.c
@@ -300,7 +300,8 @@ static int mlx5_dpll_state_on_dpll_set(const struct dpll_pin *pin,
 
 static int mlx5_dpll_ffo_get(const struct dpll_pin *pin, void *pin_priv,
 			     const struct dpll_device *dpll, void *dpll_priv,
-			     s64 *ffo, struct netlink_ext_ack *extack)
+			     struct dpll_ffo_param *ffo,
+			     struct netlink_ext_ack *extack)
 {
 	struct mlx5_dpll_synce_status synce_status;
 	struct mlx5_dpll *mdpll = pin_priv;
@@ -309,10 +310,11 @@ static int mlx5_dpll_ffo_get(const struct dpll_pin *pin, void *pin_priv,
 	err = mlx5_dpll_synce_status_get(mdpll->mdev, &synce_status);
 	if (err)
 		return err;
-	return mlx5_dpll_pin_ffo_get(&synce_status, ffo);
+	return mlx5_dpll_pin_ffo_get(&synce_status, &ffo->ffo);
 }
 
 static const struct dpll_pin_ops mlx5_dpll_pins_ops = {
+	.supported_ffo = BIT(DPLL_FFO_PORT_RXTX_RATE),
 	.direction_get = mlx5_dpll_pin_direction_get,
 	.state_on_dpll_get = mlx5_dpll_state_on_dpll_get,
 	.state_on_dpll_set = mlx5_dpll_state_on_dpll_set,
diff --git a/include/linux/dpll.h b/include/linux/dpll.h
index b6f16c884b99e..945dfde9dc54d 100644
--- a/include/linux/dpll.h
+++ b/include/linux/dpll.h
@@ -60,7 +60,20 @@ struct dpll_device_ops {
 				struct netlink_ext_ack *extack);
 };
 
+enum dpll_ffo_type {
+	DPLL_FFO_PORT_RXTX_RATE,
+	DPLL_FFO_PIN_DEVICE,
+
+	__DPLL_FFO_TYPE_MAX,
+};
+
+struct dpll_ffo_param {
+	enum dpll_ffo_type type;
+	s64 ffo;
+};
+
 struct dpll_pin_ops {
+	unsigned long supported_ffo;
 	int (*frequency_set)(const struct dpll_pin *pin, void *pin_priv,
 			     const struct dpll_device *dpll, void *dpll_priv,
 			     const u64 frequency,
@@ -121,7 +134,8 @@ struct dpll_pin_ops {
 				struct netlink_ext_ack *extack);
 	int (*ffo_get)(const struct dpll_pin *pin, void *pin_priv,
 		       const struct dpll_device *dpll, void *dpll_priv,
-		       s64 *ffo, struct netlink_ext_ack *extack);
+		       struct dpll_ffo_param *ffo,
+		       struct netlink_ext_ack *extack);
 	int (*measured_freq_get)(const struct dpll_pin *pin, void *pin_priv,
 				 const struct dpll_device *dpll,
 				 void *dpll_priv, u64 *measured_freq,
-- 
2.53.0

[PATCH net-next v4 2/2] dpll: zl3073x: report FFO as DPLL vs input reference offset

[Ivan Vecera]

Replace the per-reference frequency offset measurement (which was
redundant with measured-frequency) with a direct read of the DPLL's
delta frequency offset vs its tracked input reference.

The new implementation uses the dpll_df_offset_x register with
ref_ofst=1 via the dpll_df_read_x semaphore mechanism. This
provides 2^-48 resolution (~3.5 fE) and reports the actual
frequency difference between the DPLL and its active input.

Switch supported_ffo from DPLL_FFO_PORT_RXTX_RATE to
DPLL_FFO_PIN_DEVICE so FFO is reported only in the per-parent
context for the active input pin.

Use atomic64_t for freq_offset to prevent torn reads on 32-bit
architectures between the periodic worker and netlink callbacks.

Rewrite ffo_check to compare the cached df_offset converted to PPT
instead of using the old per-reference measurement. Remove the
ref_ffo_update periodic measurement and the ref ffo field since
they are no longer needed.

Changes v3 -> v4:
- Switch to DPLL_FFO_PIN_DEVICE, remove dpll=NULL guard
- Use atomic64_t for freq_offset (torn read on 32-bit)

Reviewed-by: Petr Oros <poros@redhat.com>
Signed-off-by: Ivan Vecera <ivecera@redhat.com>
---
 drivers/dpll/zl3073x/chan.c | 31 +++++++++++++++++++++++--
 drivers/dpll/zl3073x/chan.h | 14 ++++++++++++
 drivers/dpll/zl3073x/core.c | 45 -------------------------------------
 drivers/dpll/zl3073x/dpll.c | 38 ++++++++++++++-----------------
 drivers/dpll/zl3073x/ref.h  | 14 ------------
 drivers/dpll/zl3073x/regs.h | 15 +++++++++++++
 6 files changed, 75 insertions(+), 82 deletions(-)

diff --git a/drivers/dpll/zl3073x/chan.c b/drivers/dpll/zl3073x/chan.c
index 2f48ca2391494..2fe3c3da84bb5 100644
--- a/drivers/dpll/zl3073x/chan.c
+++ b/drivers/dpll/zl3073x/chan.c
@@ -18,6 +18,7 @@
 int zl3073x_chan_state_update(struct zl3073x_dev *zldev, u8 index)
 {
 	struct zl3073x_chan *chan = &zldev->chan[index];
+	u64 val;
 	int rc;
 
 	rc = zl3073x_read_u8(zldev, ZL_REG_DPLL_MON_STATUS(index),
@@ -25,8 +26,34 @@ int zl3073x_chan_state_update(struct zl3073x_dev *zldev, u8 index)
 	if (rc)
 		return rc;
 
-	return zl3073x_read_u8(zldev, ZL_REG_DPLL_REFSEL_STATUS(index),
-			       &chan->refsel_status);
+	rc = zl3073x_read_u8(zldev, ZL_REG_DPLL_REFSEL_STATUS(index),
+			     &chan->refsel_status);
+	if (rc)
+		return rc;
+
+	/* Read df_offset vs tracked reference */
+	rc = zl3073x_poll_zero_u8(zldev, ZL_REG_DPLL_DF_READ(index),
+				  ZL_DPLL_DF_READ_SEM);
+	if (rc)
+		return rc;
+
+	rc = zl3073x_write_u8(zldev, ZL_REG_DPLL_DF_READ(index),
+			      ZL_DPLL_DF_READ_SEM | ZL_DPLL_DF_READ_REF_OFST);
+	if (rc)
+		return rc;
+
+	rc = zl3073x_poll_zero_u8(zldev, ZL_REG_DPLL_DF_READ(index),
+				  ZL_DPLL_DF_READ_SEM);
+	if (rc)
+		return rc;
+
+	rc = zl3073x_read_u48(zldev, ZL_REG_DPLL_DF_OFFSET(index), &val);
+	if (rc)
+		return rc;
+
+	chan->df_offset = sign_extend64(val, 47);
+
+	return 0;
 }
 
 /**
diff --git a/drivers/dpll/zl3073x/chan.h b/drivers/dpll/zl3073x/chan.h
index 481da2133202b..4353809c69122 100644
--- a/drivers/dpll/zl3073x/chan.h
+++ b/drivers/dpll/zl3073x/chan.h
@@ -17,6 +17,7 @@ struct zl3073x_dev;
  * @ref_prio: reference priority registers (4 bits per ref, P/N packed)
  * @mon_status: monitor status register value
  * @refsel_status: reference selection status register value
+ * @df_offset: frequency offset vs tracked reference in 2^-48 steps
  */
 struct zl3073x_chan {
 	struct_group(cfg,
@@ -26,6 +27,7 @@ struct zl3073x_chan {
 	struct_group(stat,
 		u8	mon_status;
 		u8	refsel_status;
+		s64	df_offset;
 	);
 };
 
@@ -37,6 +39,18 @@ int zl3073x_chan_state_set(struct zl3073x_dev *zldev, u8 index,
 
 int zl3073x_chan_state_update(struct zl3073x_dev *zldev, u8 index);
 
+/**
+ * zl3073x_chan_df_offset_get - get cached df_offset vs tracked reference
+ * @chan: pointer to channel state
+ *
+ * Return: frequency offset in 2^-48 steps
+ */
+static inline s64
+zl3073x_chan_df_offset_get(const struct zl3073x_chan *chan)
+{
+	return chan->df_offset;
+}
+
 /**
  * zl3073x_chan_mode_get - get DPLL channel operating mode
  * @chan: pointer to channel state
diff --git a/drivers/dpll/zl3073x/core.c b/drivers/dpll/zl3073x/core.c
index 5f1e70f3e40a0..b3345060490db 100644
--- a/drivers/dpll/zl3073x/core.c
+++ b/drivers/dpll/zl3073x/core.c
@@ -704,44 +704,6 @@ zl3073x_ref_freq_meas_update(struct zl3073x_dev *zldev)
 	return 0;
 }
 
-/**
- * zl3073x_ref_ffo_update - update reference fractional frequency offsets
- * @zldev: pointer to zl3073x_dev structure
- *
- * The function asks device to latch the latest measured fractional
- * frequency offset values, reads and stores them into the ref state.
- *
- * Return: 0 on success, <0 on error
- */
-static int
-zl3073x_ref_ffo_update(struct zl3073x_dev *zldev)
-{
-	int i, rc;
-
-	rc = zl3073x_ref_freq_meas_latch(zldev,
-					 ZL_REF_FREQ_MEAS_CTRL_REF_FREQ_OFF);
-	if (rc)
-		return rc;
-
-	/* Read DPLL-to-REFx frequency offset measurements */
-	for (i = 0; i < ZL3073X_NUM_REFS; i++) {
-		s32 value;
-
-		/* Read value stored in units of 2^-32 signed */
-		rc = zl3073x_read_u32(zldev, ZL_REG_REF_FREQ(i), &value);
-		if (rc)
-			return rc;
-
-		/* Convert to ppt
-		 * ffo = (10^12 * value) / 2^32
-		 * ffo = ( 5^12 * value) / 2^20
-		 */
-		zldev->ref[i].ffo = mul_s64_u64_shr(value, 244140625, 20);
-	}
-
-	return 0;
-}
-
 static void
 zl3073x_dev_periodic_work(struct kthread_work *work)
 {
@@ -776,13 +738,6 @@ zl3073x_dev_periodic_work(struct kthread_work *work)
 		}
 	}
 
-	/* Update references' fractional frequency offsets */
-	rc = zl3073x_ref_ffo_update(zldev);
-	if (rc)
-		dev_warn(zldev->dev,
-			 "Failed to update fractional frequency offsets: %pe\n",
-			 ERR_PTR(rc));
-
 	list_for_each_entry(zldpll, &zldev->dplls, list)
 		zl3073x_dpll_changes_check(zldpll);
 
diff --git a/drivers/dpll/zl3073x/dpll.c b/drivers/dpll/zl3073x/dpll.c
index 05e63661bf074..cff85cdb9d0e5 100644
--- a/drivers/dpll/zl3073x/dpll.c
+++ b/drivers/dpll/zl3073x/dpll.c
@@ -1,5 +1,6 @@
 // SPDX-License-Identifier: GPL-2.0-only
 
+#include <linux/atomic.h>
 #include <linux/bits.h>
 #include <linux/bitfield.h>
 #include <linux/bug.h>
@@ -57,7 +58,7 @@ struct zl3073x_dpll_pin {
 	s32			phase_gran;
 	enum dpll_pin_operstate	operstate;
 	s64			phase_offset;
-	s64			freq_offset;
+	atomic64_t		freq_offset;
 	u32			measured_freq;
 };
 
@@ -300,7 +301,10 @@ zl3073x_dpll_input_pin_ffo_get(const struct dpll_pin *dpll_pin, void *pin_priv,
 {
 	struct zl3073x_dpll_pin *pin = pin_priv;
 
-	ffo->ffo = pin->freq_offset;
+	if (pin->operstate != DPLL_PIN_OPERSTATE_ACTIVE)
+		return -ENODATA;
+
+	ffo->ffo = atomic64_read(&pin->freq_offset);
 
 	return 0;
 }
@@ -1275,7 +1279,7 @@ zl3073x_dpll_freq_monitor_set(const struct dpll_device *dpll,
 }
 
 static const struct dpll_pin_ops zl3073x_dpll_input_pin_ops = {
-	.supported_ffo = BIT(DPLL_FFO_PORT_RXTX_RATE),
+	.supported_ffo = BIT(DPLL_FFO_PIN_DEVICE),
 	.direction_get = zl3073x_dpll_pin_direction_get,
 	.esync_get = zl3073x_dpll_input_pin_esync_get,
 	.esync_set = zl3073x_dpll_input_pin_esync_set,
@@ -1731,37 +1735,29 @@ zl3073x_dpll_pin_phase_offset_check(struct zl3073x_dpll_pin *pin)
 }
 
 /**
- * zl3073x_dpll_pin_ffo_check - check for pin fractional frequency offset change
+ * zl3073x_dpll_pin_ffo_check - check for FFO change on active pin
  * @pin: pin to check
  *
- * Check for the given pin's fractional frequency change.
- *
- * Return: true on fractional frequency offset change, false otherwise
+ * Return: true on change, false otherwise
  */
 static bool
 zl3073x_dpll_pin_ffo_check(struct zl3073x_dpll_pin *pin)
 {
 	struct zl3073x_dpll *zldpll = pin->dpll;
 	struct zl3073x_dev *zldev = zldpll->dev;
-	const struct zl3073x_ref *ref;
-	u8 ref_id;
+	const struct zl3073x_chan *chan;
 	s64 ffo;
 
-	/* Get reference monitor status */
-	ref_id = zl3073x_input_pin_ref_get(pin->id);
-	ref = zl3073x_ref_state_get(zldev, ref_id);
-
-	/* Do not report ffo changes if the reference monitor report errors */
-	if (!zl3073x_ref_is_status_ok(ref))
+	if (pin->operstate != DPLL_PIN_OPERSTATE_ACTIVE)
 		return false;
 
-	/* Compare with previous value */
-	ffo = zl3073x_ref_ffo_get(ref);
-	if (pin->freq_offset != ffo) {
-		dev_dbg(zldev->dev, "%s freq offset changed: %lld -> %lld\n",
-			pin->label, pin->freq_offset, ffo);
-		pin->freq_offset = ffo;
+	chan = zl3073x_chan_state_get(zldpll->dev, zldpll->id);
+	ffo = mul_s64_u64_shr(zl3073x_chan_df_offset_get(chan),
+			      244140625, 36);
 
+	if (atomic64_xchg(&pin->freq_offset, ffo) != ffo) {
+		dev_dbg(zldev->dev, "%s freq offset changed to: %lld\n",
+			pin->label, ffo);
 		return true;
 	}
 
diff --git a/drivers/dpll/zl3073x/ref.h b/drivers/dpll/zl3073x/ref.h
index 55e80e4f08734..e140ca3ea17dc 100644
--- a/drivers/dpll/zl3073x/ref.h
+++ b/drivers/dpll/zl3073x/ref.h
@@ -22,7 +22,6 @@ struct zl3073x_dev;
  * @freq_ratio_n: FEC mode divisor
  * @sync_ctrl: reference sync control
  * @config: reference config
- * @ffo: current fractional frequency offset
  * @meas_freq: measured input frequency in Hz
  * @mon_status: reference monitor status
  */
@@ -40,7 +39,6 @@ struct zl3073x_ref {
 		u8	config;
 	);
 	struct_group(stat, /* Status */
-		s64	ffo;
 		u32	meas_freq;
 		u8	mon_status;
 	);
@@ -58,18 +56,6 @@ int zl3073x_ref_state_update(struct zl3073x_dev *zldev, u8 index);
 
 int zl3073x_ref_freq_factorize(u32 freq, u16 *base, u16 *mult);
 
-/**
- * zl3073x_ref_ffo_get - get current fractional frequency offset
- * @ref: pointer to ref state
- *
- * Return: the latest measured fractional frequency offset
- */
-static inline s64
-zl3073x_ref_ffo_get(const struct zl3073x_ref *ref)
-{
-	return ref->ffo;
-}
-
 /**
  * zl3073x_ref_meas_freq_get - get measured input frequency
  * @ref: pointer to ref state
diff --git a/drivers/dpll/zl3073x/regs.h b/drivers/dpll/zl3073x/regs.h
index 8015808bdf548..9578f00095282 100644
--- a/drivers/dpll/zl3073x/regs.h
+++ b/drivers/dpll/zl3073x/regs.h
@@ -164,6 +164,11 @@
 #define ZL_DPLL_MODE_REFSEL_MODE_NCO		4
 #define ZL_DPLL_MODE_REFSEL_REF			GENMASK(7, 4)
 
+#define ZL_REG_DPLL_DF_READ(_idx)					\
+	ZL_REG_IDX(_idx, 5, 0x28, 1, ZL3073X_MAX_CHANNELS, 1)
+#define ZL_DPLL_DF_READ_SEM			BIT(4)
+#define ZL_DPLL_DF_READ_REF_OFST		BIT(3)
+
 #define ZL_REG_DPLL_MEAS_CTRL			ZL_REG(5, 0x50, 1)
 #define ZL_DPLL_MEAS_CTRL_EN			BIT(0)
 #define ZL_DPLL_MEAS_CTRL_AVG_FACTOR		GENMASK(7, 4)
@@ -176,6 +181,16 @@
 #define ZL_REG_DPLL_PHASE_ERR_DATA(_idx)				\
 	ZL_REG_IDX(_idx, 5, 0x55, 6, ZL3073X_MAX_CHANNELS, 6)
 
+/*******************************
+ * Register Pages 6-7, DPLL Data
+ *******************************/
+
+#define ZL_REG_DPLL_DF_OFFSET_03(_idx)					\
+	ZL_REG_IDX(_idx, 6, 0x00, 6, 4, 0x20)
+#define ZL_REG_DPLL_DF_OFFSET_4		ZL_REG(7, 0x00, 6)
+#define ZL_REG_DPLL_DF_OFFSET(_idx)					\
+	((_idx) < 4 ? ZL_REG_DPLL_DF_OFFSET_03(_idx) : ZL_REG_DPLL_DF_OFFSET_4)
+
 /***********************************
  * Register Page 9, Synth and Output
  ***********************************/
-- 
2.53.0