[RFC PATCH net-next 1/2] ethtool: add interface capabilities query (intf-caps-get)

@@ -210,6 +210,25 @@ definitions:
       -
         name: discard
         value: 31
+  -
+    name: intf-component
+    type: enum
+    doc: Type of hardware component in the interface.
+    entries:
+      - mac
+      - phy
+      - module
+  -
+    name: intf-sublayer
+    type: enum
+    doc: 802.3 sublayer within a component.
+    entries:
+      - none
+      - rs
+      - pcs
+      - fec
+      - pma
+      - pmd
 
 attribute-sets:
   -

@@ -1905,6 +1924,73 @@ attribute-sets:
         name: link
         type: nest
         nested-attributes: mse-snapshot
+  -
+    name: intf-block
+    doc: A single functional block in the interface.
+    attributes:
+      -
+        name: id
+        type: u32
+      -
+        name: component
+        type: u32
+        enum: intf-component
+      -
+        name: sublayer
+        type: u32
+        enum: intf-sublayer
+      -
+        name: instance
+        type: u32
+        doc: |
+          Identifies the hardware entity when multiple instances of
+          the same component exist in the interface. The driver
+          assigns instance numbers sequentially based on position in
+          the physical path. Defaults to 0 when only one instance of
+          a given component exists.
+          For PHY: instance 0 is the internal/host-side PHY,
+          instance 1 is an external PHY further along the path
+          toward the line side.
+          For MAC: instance 0 is the host-facing MAC, instance 1 is
+          a secondary MAC further along the data path (e.g., behind
+          an embedded switch).
+      -
+        name: name
+        type: string
+      -
+        name: depth
+        type: u8
+      -
+        name: lanes
+        type: u32
+      -
+        name: loopback-supported
+        type: u32
+      -
+        name: supported-tx-patterns
+        type: u32
+      -
+        name: supported-rx-patterns
+        type: u32
+      -
+        name: error-inject-supported
+        type: flag
+      -
+        name: bert-supported
+        type: flag
+  -
+    name: intf-caps
+    doc: Interface capabilities message.
+    attributes:
+      -
+        name: header
+        type: nest
+        nested-attributes: header
+      -
+        name: blocks
+        type: nest
+        nested-attributes: intf-block
+        multi-attr: true
 
 operations:
   enum-model: directional

@@ -2859,6 +2945,19 @@ operations:
             - worst-channel
             - link
       dump: *mse-get-op
+    -
+      name: intf-caps-get
+      doc: Get interface capabilities (functional block layout).
+      attribute-set: intf-caps
+      do: &intf-caps-get-op
+        request:
+          attributes:
+            - header
+        reply:
+          attributes:
+            - header
+            - blocks
+      dump: *intf-caps-get-op
 
 mcast-groups:
   list:

@@ -1197,6 +1197,53 @@ struct kernel_ethtool_ts_info {
  * See &struct net_device and &struct net_device_ops for documentation
  * of the generic netdev features interface.
  */
+
+#define INTF_CAPS_MAX_BLOCKS	16
+#define INTF_BLOCK_NAME_LEN	32
+
+#define LOOPBACK_SUPPORT_LOCAL	BIT(0)
+#define LOOPBACK_SUPPORT_REMOTE	BIT(1)
+
+/**
+ * struct ethtool_intf_block - Single functional block in the interface
+ * @id: Unique block identifier
+ * @component: Hardware component (MAC, PHY, MODULE)
+ * @sublayer: 802.3 sublayer (RS, PCS, FEC, PMA, PMD, or NONE)
+ * @instance: Index when multiple instances of same component exist
+ * @name: Driver-chosen label
+ * @depth: Ordering within same (component, sublayer) tuple
+ * @lanes: Number of lanes
+ * @loopback_supported: Bitmask of supported loopback directions
+ * @supported_tx_patterns: Bitmask of patterns this block can generate
+ * @supported_rx_patterns: Bitmask of patterns this block can check
+ * @error_inject_supported: Block supports bit error injection
+ * @bert_supported: Block supports BERT counters
+ */
+struct ethtool_intf_block {
+	u32 id;
+	enum intf_component component;
+	enum intf_sublayer sublayer;
+	u32 instance;
+	char name[INTF_BLOCK_NAME_LEN];
+	u8 depth;
+	u32 lanes;
+	u32 loopback_supported;
+	u32 supported_tx_patterns;
+	u32 supported_rx_patterns;
+	bool error_inject_supported;
+	bool bert_supported;
+};
+
+/**
+ * struct ethtool_intf_caps - Interface capabilities (all blocks)
+ * @num_blocks: Number of valid entries in blocks[]
+ * @blocks: Array of functional blocks
+ */
+struct ethtool_intf_caps {
+	u32 num_blocks;
+	struct ethtool_intf_block blocks[INTF_CAPS_MAX_BLOCKS];
+};
+
 struct ethtool_ops {
 	u32     supported_input_xfrm:8;
 	u32     cap_link_lanes_supported:1;

@@ -1354,6 +1401,8 @@ struct ethtool_ops {
 	int	(*set_mm)(struct net_device *dev, struct ethtool_mm_cfg *cfg,
 			  struct netlink_ext_ack *extack);
 	void	(*get_mm_stats)(struct net_device *dev, struct ethtool_mm_stats *stats);
+	int	(*get_intf_caps)(struct net_device *dev,
+				 struct ethtool_intf_caps *caps);
 };
 
 int ethtool_check_ops(const struct ethtool_ops *ops);

@@ -893,6 +893,7 @@ enum {
 	ETHTOOL_MSG_RSS_CREATE_ACT,
 	ETHTOOL_MSG_RSS_DELETE_ACT,
 	ETHTOOL_MSG_MSE_GET,
+	ETHTOOL_MSG_INTF_CAPS_GET,
 
 	__ETHTOOL_MSG_USER_CNT,
 	ETHTOOL_MSG_USER_MAX = (__ETHTOOL_MSG_USER_CNT - 1)

@@ -954,6 +955,7 @@ enum {
 	ETHTOOL_MSG_RSS_CREATE_NTF,
 	ETHTOOL_MSG_RSS_DELETE_NTF,
 	ETHTOOL_MSG_MSE_GET_REPLY,
+	ETHTOOL_MSG_INTF_CAPS_GET_REPLY,
 
 	__ETHTOOL_MSG_KERNEL_CNT,
 	ETHTOOL_MSG_KERNEL_MAX = (__ETHTOOL_MSG_KERNEL_CNT - 1)

@@ -961,4 +963,50 @@ enum {
 
 #define ETHTOOL_MCGRP_MONITOR_NAME	"monitor"
 
+/* Interface component types */
+enum intf_component {
+	INTF_COMPONENT_MAC,
+	INTF_COMPONENT_PHY,
+	INTF_COMPONENT_MODULE,
+};
+
+/* Interface sublayer types */
+enum intf_sublayer {
+	INTF_SUBLAYER_NONE,
+	INTF_SUBLAYER_RS,
+	INTF_SUBLAYER_PCS,
+	INTF_SUBLAYER_FEC,
+	INTF_SUBLAYER_PMA,
+	INTF_SUBLAYER_PMD,
+};
+
+/* Attributes of a single interface block */
+enum {
+	ETHTOOL_A_INTF_BLOCK_ID,
+	ETHTOOL_A_INTF_BLOCK_COMPONENT,
+	ETHTOOL_A_INTF_BLOCK_SUBLAYER,
+	ETHTOOL_A_INTF_BLOCK_INSTANCE,
+	ETHTOOL_A_INTF_BLOCK_NAME,
+	ETHTOOL_A_INTF_BLOCK_DEPTH,
+	ETHTOOL_A_INTF_BLOCK_LANES,
+	ETHTOOL_A_INTF_BLOCK_LOOPBACK_SUPPORTED,
+	ETHTOOL_A_INTF_BLOCK_TX_PATTERNS,
+	ETHTOOL_A_INTF_BLOCK_RX_PATTERNS,
+	ETHTOOL_A_INTF_BLOCK_ERROR_INJECT,
+	ETHTOOL_A_INTF_BLOCK_BERT,
+
+	__ETHTOOL_A_INTF_BLOCK_CNT,
+	ETHTOOL_A_INTF_BLOCK_MAX = (__ETHTOOL_A_INTF_BLOCK_CNT - 1)
+};
+
+/* Attributes of intf-caps-get message */
+enum {
+	ETHTOOL_A_INTF_CAPS_UNSPEC,
+	ETHTOOL_A_INTF_CAPS_HEADER,
+	ETHTOOL_A_INTF_CAPS_BLOCKS,
+
+	__ETHTOOL_A_INTF_CAPS_CNT,
+	ETHTOOL_A_INTF_CAPS_MAX = (__ETHTOOL_A_INTF_CAPS_CNT - 1)
+};
+
 #endif /* _UAPI_LINUX_ETHTOOL_NETLINK_GENERATED_H */

@@ -9,4 +9,4 @@ ethtool_nl-y	:= netlink.o bitset.o strset.o linkinfo.o linkmodes.o rss.o \
 		   channels.o coalesce.o pause.o eee.o tsinfo.o cabletest.o \
 		   tunnels.o fec.o eeprom.o stats.o phc_vclocks.o mm.o \
 		   module.o cmis_fw_update.o cmis_cdb.o pse-pd.o plca.o \
-		   phy.o tsconfig.o mse.o
+		   phy.o tsconfig.o mse.o intf_caps.o

@@ -0,0 +1,130 @@
+// SPDX-License-Identifier: GPL-2.0-only
+
+#include "netlink.h"
+#include "common.h"
+
+struct intf_caps_req_info {
+	struct ethnl_req_info base;
+};
+
+struct intf_caps_reply_data {
+	struct ethnl_reply_data base;
+	struct ethtool_intf_caps caps;
+};
+
+#define INTF_CAPS_REPDATA(__reply_base) \
+	container_of(__reply_base, struct intf_caps_reply_data, base)
+
+const struct nla_policy ethnl_intf_caps_get_policy[ETHTOOL_A_INTF_CAPS_HEADER + 1] = {
+	[ETHTOOL_A_INTF_CAPS_HEADER] =
+		NLA_POLICY_NESTED(ethnl_header_policy),
+};
+
+static int intf_caps_reply_size(const struct ethnl_req_info *req_base,
+				const struct ethnl_reply_data *reply_base)
+{
+	const struct intf_caps_reply_data *data = INTF_CAPS_REPDATA(reply_base);
+	int len = 0;
+	u32 i;
+
+	for (i = 0; i < data->caps.num_blocks; i++) {
+		len += nla_total_size(0);		/* nested block */
+		len += nla_total_size(sizeof(u32));	/* id */
+		len += nla_total_size(sizeof(u32));	/* component */
+		len += nla_total_size(sizeof(u32));	/* sublayer */
+		len += nla_total_size(sizeof(u32));	/* instance */
+		len += nla_total_size(INTF_BLOCK_NAME_LEN); /* name */
+		len += nla_total_size(sizeof(u8));	/* depth */
+		len += nla_total_size(sizeof(u32));	/* lanes */
+		len += nla_total_size(sizeof(u32));	/* loopback_supported */
+		len += nla_total_size(sizeof(u32));	/* tx_patterns */
+		len += nla_total_size(sizeof(u32));	/* rx_patterns */
+		len += nla_total_size(0);		/* error_inject (flag) */
+		len += nla_total_size(0);		/* bert (flag) */
+	}
+
+	/* outer BLOCKS nest */
+	len += nla_total_size(0);
+
+	return len;
+}
+
+static int intf_caps_prepare_data(const struct ethnl_req_info *req_base,
+				  struct ethnl_reply_data *reply_base,
+				  const struct genl_info *info)
+{
+	struct intf_caps_reply_data *data = INTF_CAPS_REPDATA(reply_base);
+	struct net_device *dev = reply_base->dev;
+
+	if (!dev->ethtool_ops->get_intf_caps)
+		return -EOPNOTSUPP;
+
+	return dev->ethtool_ops->get_intf_caps(dev, &data->caps);
+}
+
+static int intf_caps_fill_reply(struct sk_buff *skb,
+				const struct ethnl_req_info *req_base,
+				const struct ethnl_reply_data *reply_base)
+{
+	const struct intf_caps_reply_data *data = INTF_CAPS_REPDATA(reply_base);
+	struct nlattr *blocks_attr;
+	u32 i;
+
+	blocks_attr = nla_nest_start(skb, ETHTOOL_A_INTF_CAPS_BLOCKS);
+	if (!blocks_attr)
+		return -EMSGSIZE;
+
+	for (i = 0; i < data->caps.num_blocks; i++) {
+		const struct ethtool_intf_block *b = &data->caps.blocks[i];
+		struct nlattr *block_attr;
+
+		block_attr = nla_nest_start(skb, 0);
+		if (!block_attr)
+			goto nla_put_failure;
+
+		if (nla_put_u32(skb, ETHTOOL_A_INTF_BLOCK_ID, b->id) ||
+		    nla_put_u32(skb, ETHTOOL_A_INTF_BLOCK_COMPONENT,
+				b->component) ||
+		    nla_put_u32(skb, ETHTOOL_A_INTF_BLOCK_SUBLAYER,
+				b->sublayer) ||
+		    nla_put_u32(skb, ETHTOOL_A_INTF_BLOCK_INSTANCE,
+				b->instance) ||
+		    nla_put_string(skb, ETHTOOL_A_INTF_BLOCK_NAME, b->name) ||
+		    nla_put_u8(skb, ETHTOOL_A_INTF_BLOCK_DEPTH, b->depth) ||
+		    nla_put_u32(skb, ETHTOOL_A_INTF_BLOCK_LANES, b->lanes) ||
+		    nla_put_u32(skb, ETHTOOL_A_INTF_BLOCK_LOOPBACK_SUPPORTED,
+				b->loopback_supported) ||
+		    nla_put_u32(skb, ETHTOOL_A_INTF_BLOCK_TX_PATTERNS,
+				b->supported_tx_patterns) ||
+		    nla_put_u32(skb, ETHTOOL_A_INTF_BLOCK_RX_PATTERNS,
+				b->supported_rx_patterns))
+			goto nla_put_failure;
+		if (b->error_inject_supported &&
+		    nla_put_flag(skb, ETHTOOL_A_INTF_BLOCK_ERROR_INJECT))
+			goto nla_put_failure;
+		if (b->bert_supported &&
+		    nla_put_flag(skb, ETHTOOL_A_INTF_BLOCK_BERT))
+			goto nla_put_failure;
+			goto nla_put_failure;
+
+		nla_nest_end(skb, block_attr);
+	}
+
+	nla_nest_end(skb, blocks_attr);
+	return 0;
+
+nla_put_failure:
+	nla_nest_cancel(skb, blocks_attr);
+	return -EMSGSIZE;
+}
+
+const struct ethnl_request_ops ethnl_intf_caps_request_ops = {
+	.request_cmd	= ETHTOOL_MSG_INTF_CAPS_GET,
+	.reply_cmd	= ETHTOOL_MSG_INTF_CAPS_GET_REPLY,
+	.hdr_attr	= ETHTOOL_A_INTF_CAPS_HEADER,
+	.req_info_size	= sizeof(struct intf_caps_req_info),
+	.reply_data_size = sizeof(struct intf_caps_reply_data),
+	.prepare_data	= intf_caps_prepare_data,
+	.reply_size	= intf_caps_reply_size,
+	.fill_reply	= intf_caps_fill_reply,
+};

@@ -431,6 +431,7 @@ ethnl_default_requests[__ETHTOOL_MSG_USER_CNT] = {
 	[ETHTOOL_MSG_TSCONFIG_SET]	= &ethnl_tsconfig_request_ops,
 	[ETHTOOL_MSG_PHY_GET]		= &ethnl_phy_request_ops,
 	[ETHTOOL_MSG_MSE_GET]		= &ethnl_mse_request_ops,
+	[ETHTOOL_MSG_INTF_CAPS_GET]	= &ethnl_intf_caps_request_ops,
 };
 
 static struct ethnl_dump_ctx *ethnl_dump_context(struct netlink_callback *cb)

@@ -1572,6 +1573,15 @@ static const struct genl_ops ethtool_genl_ops[] = {
 		.policy = ethnl_mse_get_policy,
 		.maxattr = ARRAY_SIZE(ethnl_mse_get_policy) - 1,
 	},
+	{
+		.cmd	= ETHTOOL_MSG_INTF_CAPS_GET,
+		.doit	= ethnl_default_doit,
+		.start	= ethnl_default_start,
+		.dumpit	= ethnl_default_dumpit,
+		.done	= ethnl_default_done,
+		.policy = ethnl_intf_caps_get_policy,
+		.maxattr = ARRAY_SIZE(ethnl_intf_caps_get_policy) - 1,
+	},
 };
 
 static const struct genl_multicast_group ethtool_nl_mcgrps[] = {

@@ -474,6 +474,7 @@ extern const struct ethnl_request_ops ethnl_mm_request_ops;
 extern const struct ethnl_request_ops ethnl_phy_request_ops;
 extern const struct ethnl_request_ops ethnl_tsconfig_request_ops;
 extern const struct ethnl_request_ops ethnl_mse_request_ops;
+extern const struct ethnl_request_ops ethnl_intf_caps_request_ops;
 
 extern const struct nla_policy ethnl_header_policy[ETHTOOL_A_HEADER_FLAGS + 1];
 extern const struct nla_policy ethnl_header_policy_stats[ETHTOOL_A_HEADER_FLAGS + 1];

@@ -530,6 +531,7 @@ extern const struct nla_policy ethnl_phy_get_policy[ETHTOOL_A_PHY_HEADER + 1];
 extern const struct nla_policy ethnl_tsconfig_get_policy[ETHTOOL_A_TSCONFIG_HEADER + 1];
 extern const struct nla_policy ethnl_tsconfig_set_policy[ETHTOOL_A_TSCONFIG_MAX + 1];
 extern const struct nla_policy ethnl_mse_get_policy[ETHTOOL_A_MSE_HEADER + 1];
+extern const struct nla_policy ethnl_intf_caps_get_policy[ETHTOOL_A_INTF_CAPS_HEADER + 1];
 
 int ethnl_set_features(struct sk_buff *skb, struct genl_info *info);
 int ethnl_act_cable_test(struct sk_buff *skb, struct genl_info *info);