Merge branch 'devlink-add-device-driver-information-API'

Jakub Kicinski says:

====================
devlink: add device (driver) information API

fw_version field in ethtool -i does not suit modern needs with 31
characters being quite limiting on more complex systems.  There is
also no distinction between the running and flashed versions of
the firmware.

Since the driver information pertains to the entire device, rather
than a particular netdev, it seems wise to move it do devlink, at
the same time fixing the aforementioned issues.

The new API allows exposing the device serial number and versions
of the components of the card - both hardware, firmware (running
and flashed).  Driver authors can choose descriptive identifiers
for the version fields.  A few version identifiers which seemed
relevant for most devices have been added to the global devlink
header.

Example:
$ devlink dev info pci/0000:05:00.0
pci/0000:05:00.0:
  driver nfp
  serial_number 16240145
  versions:
    fixed:
      board.id AMDA0099-0001
      board.rev 07
      board.vendor SMA
      board.model carbon
    running:
      fw.mgmt: 010156.010156.010156
      fw.cpld: 0x44
      fw.app: sriov-2.1.16
    stored:
      fw.mgmt: 010158.010158.010158
      fw.cpld: 0x44
      fw.app: sriov-2.1.20

Last patch also includes a compat code for ethtool.  If driver
reports no fw_version via the traditional ethtool API, ethtool
can call into devlink and try to cram as many versions as possible
into the 31 characters.

v4:
 - use IS_REACHABLE instead of IS_ENABLED in last patch.

v3 (Jiri):
 - rename various functions and attributes;
 - break out the version helpers per-type;
 - make the compat code parse a dump instead of special casing
   in each helper;
 - move generic version defines to a separate patch.

v2:
 - rebase.

this non-RFC, v3 some would say:
 - add three more versions in the NFP patches;
 - add last patch (ethool compat) - Andrew & Michal.

RFCv2:
 - use one driver op;
 - allow longer serial number;
 - wrap the skb into an opaque request struct;
 - add some common identifier into the devlink header.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>

2 files changed, 85 insertions, 0 deletions

diff --git a/include/net/devlink.h b/include/net/devlink.h
index 85c9eabaf056..1c8523920f66 100644
--- a/include/net/devlink.h
+++ b/include/net/devlink.h
@@ -428,7 +428,22 @@ enum devlink_param_wol_types {
 	.validate = _validate,						\
 }
 
+/* Part number, identifier of board design */
+#define DEVLINK_INFO_VERSION_GENERIC_BOARD_ID	"board.id"
+/* Revision of board design */
+#define DEVLINK_INFO_VERSION_GENERIC_BOARD_REV	"board.rev"
+
+/* Control processor FW version */
+#define DEVLINK_INFO_VERSION_GENERIC_FW_MGMT	"fw.mgmt"
+/* Data path microcode controlling high-speed packet processing */
+#define DEVLINK_INFO_VERSION_GENERIC_FW_APP	"fw.app"
+/* UNDI software version */
+#define DEVLINK_INFO_VERSION_GENERIC_FW_UNDI	"fw.undi"
+/* NCSI support/handler version */
+#define DEVLINK_INFO_VERSION_GENERIC_FW_NCSI	"fw.ncsi"
+
 struct devlink_region;
+struct devlink_info_req;
 
 typedef void devlink_snapshot_data_dest_t(const void *data);
 
@@ -484,6 +499,8 @@ struct devlink_ops {
 	int (*eswitch_encap_mode_get)(struct devlink *devlink, u8 *p_encap_mode);
 	int (*eswitch_encap_mode_set)(struct devlink *devlink, u8 encap_mode,
 				      struct netlink_ext_ack *extack);
+	int (*info_get)(struct devlink *devlink, struct devlink_info_req *req,
+			struct netlink_ext_ack *extack);
 };
 
 static inline void *devlink_priv(struct devlink *devlink)
@@ -607,6 +624,19 @@ u32 devlink_region_shapshot_id_get(struct devlink *devlink);
 int devlink_region_snapshot_create(struct devlink_region *region, u64 data_len,
 				   u8 *data, u32 snapshot_id,
 				   devlink_snapshot_data_dest_t *data_destructor);
+int devlink_info_serial_number_put(struct devlink_info_req *req,
+				   const char *sn);
+int devlink_info_driver_name_put(struct devlink_info_req *req,
+				 const char *name);
+int devlink_info_version_fixed_put(struct devlink_info_req *req,
+				   const char *version_name,
+				   const char *version_value);
+int devlink_info_version_stored_put(struct devlink_info_req *req,
+				    const char *version_name,
+				    const char *version_value);
+int devlink_info_version_running_put(struct devlink_info_req *req,
+				     const char *version_name,
+				     const char *version_value);
 
 #else
 
@@ -905,6 +935,51 @@ devlink_region_snapshot_create(struct devlink_region *region, u64 data_len,
 	return 0;
 }
 
+static inline int
+devlink_info_driver_name_put(struct devlink_info_req *req, const char *name)
+{
+	return 0;
+}
+
+static inline int
+devlink_info_serial_number_put(struct devlink_info_req *req, const char *sn)
+{
+	return 0;
+}
+
+static inline int
+devlink_info_version_fixed_put(struct devlink_info_req *req,
+			       const char *version_name,
+			       const char *version_value)
+{
+	return 0;
+}
+
+static inline int
+devlink_info_version_stored_put(struct devlink_info_req *req,
+				const char *version_name,
+				const char *version_value)
+{
+	return 0;
+}
+
+static inline int
+devlink_info_version_running_put(struct devlink_info_req *req,
+				 const char *version_name,
+				 const char *version_value)
+{
+	return 0;
+}
+#endif
+
+#if IS_REACHABLE(CONFIG_NET_DEVLINK)
+void devlink_compat_running_version(struct net_device *dev,
+				    char *buf, size_t len);
+#else
+static inline void
+devlink_compat_running_version(struct net_device *dev, char *buf, size_t len)
+{
+}
 #endif
 
 #endif /* _NET_DEVLINK_H_ */
diff --git a/include/uapi/linux/devlink.h b/include/uapi/linux/devlink.h
index 61b4447a6c5b..7fffd879c328 100644
--- a/include/uapi/linux/devlink.h
+++ b/include/uapi/linux/devlink.h
@@ -94,6 +94,8 @@ enum devlink_command {
 	DEVLINK_CMD_PORT_PARAM_NEW,
 	DEVLINK_CMD_PORT_PARAM_DEL,
 
+	DEVLINK_CMD_INFO_GET,		/* can dump */
+
 	/* add new commands above here */
 	__DEVLINK_CMD_MAX,
 	DEVLINK_CMD_MAX = __DEVLINK_CMD_MAX - 1
@@ -290,6 +292,14 @@ enum devlink_attr {
 	DEVLINK_ATTR_REGION_CHUNK_ADDR,         /* u64 */
 	DEVLINK_ATTR_REGION_CHUNK_LEN,          /* u64 */
 
+	DEVLINK_ATTR_INFO_DRIVER_NAME,		/* string */
+	DEVLINK_ATTR_INFO_SERIAL_NUMBER,	/* string */
+	DEVLINK_ATTR_INFO_VERSION_FIXED,	/* nested */
+	DEVLINK_ATTR_INFO_VERSION_RUNNING,	/* nested */
+	DEVLINK_ATTR_INFO_VERSION_STORED,	/* nested */
+	DEVLINK_ATTR_INFO_VERSION_NAME,		/* string */
+	DEVLINK_ATTR_INFO_VERSION_VALUE,	/* string */
+
 	/* add new attributes above here, update the policy in devlink.c */
 
 	__DEVLINK_ATTR_MAX,