Thread (6 messages) 6 messages, 3 authors, 2024-08-27
STALE664d REVIEWED: 1 (0M)
Revisions (3)
  1. v1 [diff vs current]
  2. v2 [diff vs current]
  3. v3 current

[PATCH net-next v3 1/2] dpll: add Embedded SYNC feature for a pin

From: Arkadiusz Kubalewski <arkadiusz.kubalewski@intel.com>
Date: 2024-08-22 22:29:39
Also in: intel-wired-lan, linux-doc, lkml
Subsystem: documentation, dpll subsystem, networking [general], the rest, yaml netlink (ynl) · Maintainers: Jonathan Corbet, Vadim Fedorenko, Arkadiusz Kubalewski, Jiri Pirko, "David S. Miller", Eric Dumazet, Jakub Kicinski, Paolo Abeni, Linus Torvalds, Donald Hunter

Implement and document new pin attributes for providing Embedded SYNC
capabilities to the DPLL subsystem users through a netlink pin-get
do/dump messages. Allow the user to set Embedded SYNC frequency with
pin-set do netlink message.

Reviewed-by: Aleksandr Loktionov <redacted>
Signed-off-by: Arkadiusz Kubalewski <arkadiusz.kubalewski@intel.com>
---
v3:
- rename esync_freq -> freq
- fix missing space between ':' and dpll_id value in the extack error
- fix wrong indent of arguments

 Documentation/driver-api/dpll.rst     |  21 +++++
 Documentation/netlink/specs/dpll.yaml |  24 +++++
 drivers/dpll/dpll_netlink.c           | 130 ++++++++++++++++++++++++++
 drivers/dpll/dpll_nl.c                |   5 +-
 include/linux/dpll.h                  |  15 +++
 include/uapi/linux/dpll.h             |   3 +
 6 files changed, 196 insertions(+), 2 deletions(-)
diff --git a/Documentation/driver-api/dpll.rst b/Documentation/driver-api/dpll.rst
index ea8d16600e16..e6855cd37e85 100644
--- a/Documentation/driver-api/dpll.rst
+++ b/Documentation/driver-api/dpll.rst
@@ -214,6 +214,27 @@ offset values are fractional with 3-digit decimal places and shell be
 divided with ``DPLL_PIN_PHASE_OFFSET_DIVIDER`` to get integer part and
 modulo divided to get fractional part.
 
+Embedded SYNC
+=============
+
+Device may provide ability to use Embedded SYNC feature. It allows
+to embed additional SYNC signal into the base frequency of a pin - a one
+special pulse of base frequency signal every time SYNC signal pulse
+happens. The user can configure the frequency of Embedded SYNC.
+The Embedded SYNC capability is always related to a given base frequency
+and HW capabilities. The user is provided a range of Embedded SYNC
+frequencies supported, depending on current base frequency configured for
+the pin.
+
+  ========================================= =================================
+  ``DPLL_A_PIN_ESYNC_FREQUENCY``            current Embedded SYNC frequency
+  ``DPLL_A_PIN_ESYNC_FREQUENCY_SUPPORTED``  nest available Embedded SYNC
+                                            frequency ranges
+    ``DPLL_A_PIN_FREQUENCY_MIN``            attr minimum value of frequency
+    ``DPLL_A_PIN_FREQUENCY_MAX``            attr maximum value of frequency
+  ``DPLL_A_PIN_ESYNC_PULSE``                pulse type of Embedded SYNC
+  ========================================= =================================
+
 Configuration commands group
 ============================
 
diff --git a/Documentation/netlink/specs/dpll.yaml b/Documentation/netlink/specs/dpll.yaml
index 94132d30e0e0..f2894ca35de8 100644
--- a/Documentation/netlink/specs/dpll.yaml
+++ b/Documentation/netlink/specs/dpll.yaml
@@ -345,6 +345,26 @@ attribute-sets:
           Value is in PPM (parts per million).
           This may be implemented for example for pin of type
           PIN_TYPE_SYNCE_ETH_PORT.
+      -
+        name: esync-frequency
+        type: u64
+        doc: |
+          Frequency of Embedded SYNC signal. If provided, the pin is configured
+          with a SYNC signal embedded into its base clock frequency.
+      -
+        name: esync-frequency-supported
+        type: nest
+        multi-attr: true
+        nested-attributes: frequency-range
+        doc: |
+          If provided a pin is capable of embedding a SYNC signal (within given
+          range) into its base frequency signal.
+      -
+        name: esync-pulse
+        type: u32
+        doc: |
+          A ratio of high to low state of a SYNC signal pulse embedded
+          into base clock frequency. Value is in percents.
   -
     name: pin-parent-device
     subset-of: pin
@@ -510,6 +530,9 @@ operations:
             - phase-adjust-max
             - phase-adjust
             - fractional-frequency-offset
+            - esync-frequency
+            - esync-frequency-supported
+            - esync-pulse
 
       dump:
         request:
@@ -536,6 +559,7 @@ operations:
             - parent-device
             - parent-pin
             - phase-adjust
+            - esync-frequency
     -
       name: pin-create-ntf
       doc: Notification about pin appearing
diff --git a/drivers/dpll/dpll_netlink.c b/drivers/dpll/dpll_netlink.c
index 98e6ad8528d3..fc0280dcddd1 100644
--- a/drivers/dpll/dpll_netlink.c
+++ b/drivers/dpll/dpll_netlink.c
@@ -342,6 +342,51 @@ dpll_msg_add_pin_freq(struct sk_buff *msg, struct dpll_pin *pin,
 	return 0;
 }
 
+static int
+dpll_msg_add_pin_esync(struct sk_buff *msg, struct dpll_pin *pin,
+		       struct dpll_pin_ref *ref, struct netlink_ext_ack *extack)
+{
+	const struct dpll_pin_ops *ops = dpll_pin_ops(ref);
+	struct dpll_device *dpll = ref->dpll;
+	struct dpll_pin_esync esync;
+	struct nlattr *nest;
+	int ret, i;
+
+	if (!ops->esync_get)
+		return 0;
+	ret = ops->esync_get(pin, dpll_pin_on_dpll_priv(dpll, pin), dpll,
+			     dpll_priv(dpll), &esync, extack);
+	if (ret == -EOPNOTSUPP)
+		return 0;
+	else if (ret)
+		return ret;
+	if (nla_put_64bit(msg, DPLL_A_PIN_ESYNC_FREQUENCY, sizeof(esync.freq),
+			  &esync.freq, DPLL_A_PIN_PAD))
+		return -EMSGSIZE;
+	if (nla_put_u32(msg, DPLL_A_PIN_ESYNC_PULSE, esync.pulse))
+		return -EMSGSIZE;
+	for (i = 0; i < esync.range_num; i++) {
+		nest = nla_nest_start(msg,
+				      DPLL_A_PIN_ESYNC_FREQUENCY_SUPPORTED);
+		if (!nest)
+			return -EMSGSIZE;
+		if (nla_put_64bit(msg, DPLL_A_PIN_FREQUENCY_MIN,
+				  sizeof(esync.range[i].min),
+				  &esync.range[i].min, DPLL_A_PIN_PAD))
+			goto nest_cancel;
+		if (nla_put_64bit(msg, DPLL_A_PIN_FREQUENCY_MAX,
+				  sizeof(esync.range[i].max),
+				  &esync.range[i].max, DPLL_A_PIN_PAD))
+			goto nest_cancel;
+		nla_nest_end(msg, nest);
+	}
+	return 0;
+
+nest_cancel:
+	nla_nest_cancel(msg, nest);
+	return -EMSGSIZE;
+}
+
 static bool dpll_pin_is_freq_supported(struct dpll_pin *pin, u32 freq)
 {
 	int fs;
@@ -481,6 +526,9 @@ dpll_cmd_pin_get_one(struct sk_buff *msg, struct dpll_pin *pin,
 	if (ret)
 		return ret;
 	ret = dpll_msg_add_ffo(msg, pin, ref, extack);
+	if (ret)
+		return ret;
+	ret = dpll_msg_add_pin_esync(msg, pin, ref, extack);
 	if (ret)
 		return ret;
 	if (xa_empty(&pin->parent_refs))
@@ -738,6 +786,83 @@ dpll_pin_freq_set(struct dpll_pin *pin, struct nlattr *a,
 	return ret;
 }
 
+static int
+dpll_pin_esync_set(struct dpll_pin *pin, struct nlattr *a,
+		   struct netlink_ext_ack *extack)
+{
+	struct dpll_pin_ref *ref, *failed;
+	const struct dpll_pin_ops *ops;
+	struct dpll_pin_esync esync;
+	u64 freq = nla_get_u64(a);
+	struct dpll_device *dpll;
+	bool supported = false;
+	unsigned long i;
+	int ret;
+
+	xa_for_each(&pin->dpll_refs, i, ref) {
+		ops = dpll_pin_ops(ref);
+		if (!ops->esync_set || !ops->esync_get) {
+			NL_SET_ERR_MSG(extack,
+				       "embedded sync feature is not supported by this device");
+			return -EOPNOTSUPP;
+		}
+	}
+	ref = dpll_xa_ref_dpll_first(&pin->dpll_refs);
+	ops = dpll_pin_ops(ref);
+	dpll = ref->dpll;
+	ret = ops->esync_get(pin, dpll_pin_on_dpll_priv(dpll, pin), dpll,
+			     dpll_priv(dpll), &esync, extack);
+	if (ret) {
+		NL_SET_ERR_MSG(extack, "unable to get current embedded sync frequency value");
+		return ret;
+	}
+	if (freq == esync.freq)
+		return 0;
+	for (i = 0; i < esync.range_num; i++)
+		if (freq <= esync.range[i].max && freq >= esync.range[i].min)
+			supported = true;
+	if (!supported) {
+		NL_SET_ERR_MSG_ATTR(extack, a,
+				    "requested embedded sync frequency value is not supported by this device");
+		return -EINVAL;
+	}
+
+	xa_for_each(&pin->dpll_refs, i, ref) {
+		void *pin_dpll_priv;
+
+		ops = dpll_pin_ops(ref);
+		dpll = ref->dpll;
+		pin_dpll_priv = dpll_pin_on_dpll_priv(dpll, pin);
+		ret = ops->esync_set(pin, pin_dpll_priv, dpll, dpll_priv(dpll),
+				      freq, extack);
+		if (ret) {
+			failed = ref;
+			NL_SET_ERR_MSG_FMT(extack,
+					   "embedded sync frequency set failed for dpll_id: %u",
+					   dpll->id);
+			goto rollback;
+		}
+	}
+	__dpll_pin_change_ntf(pin);
+
+	return 0;
+
+rollback:
+	xa_for_each(&pin->dpll_refs, i, ref) {
+		void *pin_dpll_priv;
+
+		if (ref == failed)
+			break;
+		ops = dpll_pin_ops(ref);
+		dpll = ref->dpll;
+		pin_dpll_priv = dpll_pin_on_dpll_priv(dpll, pin);
+		if (ops->esync_set(pin, pin_dpll_priv, dpll, dpll_priv(dpll),
+				   esync.freq, extack))
+			NL_SET_ERR_MSG(extack, "set embedded sync frequency rollback failed");
+	}
+	return ret;
+}
+
 static int
 dpll_pin_on_pin_state_set(struct dpll_pin *pin, u32 parent_idx,
 			  enum dpll_pin_state state,
@@ -1039,6 +1164,11 @@ dpll_pin_set_from_nlattr(struct dpll_pin *pin, struct genl_info *info)
 			if (ret)
 				return ret;
 			break;
+		case DPLL_A_PIN_ESYNC_FREQUENCY:
+			ret = dpll_pin_esync_set(pin, a, info->extack);
+			if (ret)
+				return ret;
+			break;
 		}
 	}
 
diff --git a/drivers/dpll/dpll_nl.c b/drivers/dpll/dpll_nl.c
index 1e95f5397cfc..fe9b6893d261 100644
--- a/drivers/dpll/dpll_nl.c
+++ b/drivers/dpll/dpll_nl.c
@@ -62,7 +62,7 @@ static const struct nla_policy dpll_pin_get_dump_nl_policy[DPLL_A_PIN_ID + 1] =
 };
 
 /* DPLL_CMD_PIN_SET - do */
-static const struct nla_policy dpll_pin_set_nl_policy[DPLL_A_PIN_PHASE_ADJUST + 1] = {
+static const struct nla_policy dpll_pin_set_nl_policy[DPLL_A_PIN_ESYNC_FREQUENCY + 1] = {
 	[DPLL_A_PIN_ID] = { .type = NLA_U32, },
 	[DPLL_A_PIN_FREQUENCY] = { .type = NLA_U64, },
 	[DPLL_A_PIN_DIRECTION] = NLA_POLICY_RANGE(NLA_U32, 1, 2),
@@ -71,6 +71,7 @@ static const struct nla_policy dpll_pin_set_nl_policy[DPLL_A_PIN_PHASE_ADJUST +
 	[DPLL_A_PIN_PARENT_DEVICE] = NLA_POLICY_NESTED(dpll_pin_parent_device_nl_policy),
 	[DPLL_A_PIN_PARENT_PIN] = NLA_POLICY_NESTED(dpll_pin_parent_pin_nl_policy),
 	[DPLL_A_PIN_PHASE_ADJUST] = { .type = NLA_S32, },
+	[DPLL_A_PIN_ESYNC_FREQUENCY] = { .type = NLA_U64, },
 };
 
 /* Ops table for dpll */
@@ -138,7 +139,7 @@ static const struct genl_split_ops dpll_nl_ops[] = {
 		.doit		= dpll_nl_pin_set_doit,
 		.post_doit	= dpll_pin_post_doit,
 		.policy		= dpll_pin_set_nl_policy,
-		.maxattr	= DPLL_A_PIN_PHASE_ADJUST,
+		.maxattr	= DPLL_A_PIN_ESYNC_FREQUENCY,
 		.flags		= GENL_ADMIN_PERM | GENL_CMD_CAP_DO,
 	},
 };
diff --git a/include/linux/dpll.h b/include/linux/dpll.h
index d275736230b3..81f7b623d0ba 100644
--- a/include/linux/dpll.h
+++ b/include/linux/dpll.h
@@ -15,6 +15,7 @@
 
 struct dpll_device;
 struct dpll_pin;
+struct dpll_pin_esync;
 
 struct dpll_device_ops {
 	int (*mode_get)(const struct dpll_device *dpll, void *dpll_priv,
@@ -83,6 +84,13 @@ struct dpll_pin_ops {
 	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);
+	int (*esync_set)(const struct dpll_pin *pin, void *pin_priv,
+			 const struct dpll_device *dpll, void *dpll_priv,
+			 u64 freq, struct netlink_ext_ack *extack);
+	int (*esync_get)(const struct dpll_pin *pin, void *pin_priv,
+			 const struct dpll_device *dpll, void *dpll_priv,
+			 struct dpll_pin_esync *esync,
+			 struct netlink_ext_ack *extack);
 };
 
 struct dpll_pin_frequency {
@@ -111,6 +119,13 @@ struct dpll_pin_phase_adjust_range {
 	s32 max;
 };
 
+struct dpll_pin_esync {
+	u64 freq;
+	const struct dpll_pin_frequency *range;
+	u8 range_num;
+	u8 pulse;
+};
+
 struct dpll_pin_properties {
 	const char *board_label;
 	const char *panel_label;
diff --git a/include/uapi/linux/dpll.h b/include/uapi/linux/dpll.h
index 0c13d7f1a1bc..b0654ade7b7e 100644
--- a/include/uapi/linux/dpll.h
+++ b/include/uapi/linux/dpll.h
@@ -210,6 +210,9 @@ enum dpll_a_pin {
 	DPLL_A_PIN_PHASE_ADJUST,
 	DPLL_A_PIN_PHASE_OFFSET,
 	DPLL_A_PIN_FRACTIONAL_FREQUENCY_OFFSET,
+	DPLL_A_PIN_ESYNC_FREQUENCY,
+	DPLL_A_PIN_ESYNC_FREQUENCY_SUPPORTED,
+	DPLL_A_PIN_ESYNC_PULSE,
 
 	__DPLL_A_PIN_MAX,
 	DPLL_A_PIN_MAX = (__DPLL_A_PIN_MAX - 1)
-- 
2.38.1
Keyboard shortcuts
hback out one level
jnext message in thread
kprevious message in thread
ldrill in
Escclose help / fold thread tree
?toggle this help