ethtool: provide UAPI for PHY Signal Quality Index (SQI)

Signal Quality Index is a mandatory value required by "OPEN Alliance
SIG" for the 100Base-T1 PHYs [1]. This indicator can be used for cable
integrity diagnostic and investigating other noise sources and
implement by at least two vendors: NXP[2] and TI[3].

[1] http://www.opensig.org/download/document/218/Advanced_PHY_features_for_automotive_Ethernet_V1.0.pdf
[2] https://www.nxp.com/docs/en/data-sheet/TJA1100.pdf
[3] https://www.ti.com/product/DP83TC811R-Q1

Signed-off-by: Oleksij Rempel <o.rempel@pengutronix.de>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Reviewed-by: Michal Kubecek <mkubecek@suse.cz>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/Documentation/networking/ethtool-netlink.rst b/Documentation/networking/ethtool-netlink.rst
index eed46b6..7e651ea 100644 (file)
--- a/Documentation/networking/ethtool-netlink.rst
+++ b/Documentation/networking/ethtool-netlink.rst
@@ -454,10 +454,12 @@ Request contents:
 
 Kernel response contents:
 
-  ====================================  ======  ==========================
+  ====================================  ======  ============================
   ``ETHTOOL_A_LINKSTATE_HEADER``        nested  reply header
   ``ETHTOOL_A_LINKSTATE_LINK``          bool    link state (up/down)
-  ====================================  ======  ==========================
+  ``ETHTOOL_A_LINKSTATE_SQI``           u32     Current Signal Quality Index
+  ``ETHTOOL_A_LINKSTATE_SQI_MAX``       u32     Max support SQI value
+  ====================================  ======  ============================
 
 For most NIC drivers, the value of ``ETHTOOL_A_LINKSTATE_LINK`` returns
 carrier flag provided by ``netif_carrier_ok()`` but there are drivers which

diff --git a/include/linux/phy.h b/include/linux/phy.h
index 467aa8b..2bcdf19 100644 (file)
--- a/include/linux/phy.h
+++ b/include/linux/phy.h
@@ -723,6 +723,8 @@ struct phy_driver {
                            struct ethtool_tunable *tuna,
                            const void *data);
        int (*set_loopback)(struct phy_device *dev, bool enable);
+       int (*get_sqi)(struct phy_device *dev);
+       int (*get_sqi_max)(struct phy_device *dev);
 };
 #define to_phy_driver(d) container_of(to_mdio_common_driver(d),                \
                                      struct phy_driver, mdiodrv)

diff --git a/include/uapi/linux/ethtool_netlink.h b/include/uapi/linux/ethtool_netlink.h
index 2881af4..e6f109b 100644 (file)
--- a/include/uapi/linux/ethtool_netlink.h
+++ b/include/uapi/linux/ethtool_netlink.h
@@ -232,6 +232,8 @@ enum {
        ETHTOOL_A_LINKSTATE_UNSPEC,
        ETHTOOL_A_LINKSTATE_HEADER,             /* nest - _A_HEADER_* */
        ETHTOOL_A_LINKSTATE_LINK,               /* u8 */
+       ETHTOOL_A_LINKSTATE_SQI,                /* u32 */
+       ETHTOOL_A_LINKSTATE_SQI_MAX,            /* u32 */
 
        /* add new constants above here */
        __ETHTOOL_A_LINKSTATE_CNT,

diff --git a/net/ethtool/linkstate.c b/net/ethtool/linkstate.c
index 2740cde..7f47ba8 100644 (file)
--- a/net/ethtool/linkstate.c
+++ b/net/ethtool/linkstate.c
@@ -2,6 +2,7 @@
 
 #include "netlink.h"
 #include "common.h"
+#include <linux/phy.h>
 
 struct linkstate_req_info {
        struct ethnl_req_info           base;
@@ -10,6 +11,8 @@ struct linkstate_req_info {
 struct linkstate_reply_data {
        struct ethnl_reply_data         base;
        int                             link;
+       int                             sqi;
+       int                             sqi_max;
 };
 
 #define LINKSTATE_REPDATA(__reply_base) \
@@ -20,8 +23,46 @@ linkstate_get_policy[ETHTOOL_A_LINKSTATE_MAX + 1] = {
        [ETHTOOL_A_LINKSTATE_UNSPEC]            = { .type = NLA_REJECT },
        [ETHTOOL_A_LINKSTATE_HEADER]            = { .type = NLA_NESTED },
        [ETHTOOL_A_LINKSTATE_LINK]              = { .type = NLA_REJECT },
+       [ETHTOOL_A_LINKSTATE_SQI]               = { .type = NLA_REJECT },
+       [ETHTOOL_A_LINKSTATE_SQI_MAX]           = { .type = NLA_REJECT },
 };
 
+static int linkstate_get_sqi(struct net_device *dev)
+{
+       struct phy_device *phydev = dev->phydev;
+       int ret;
+
+       if (!phydev)
+               return -EOPNOTSUPP;
+
+       mutex_lock(&phydev->lock);
+       if (!phydev->drv || !phydev->drv->get_sqi)
+               ret = -EOPNOTSUPP;
+       else
+               ret = phydev->drv->get_sqi(phydev);
+       mutex_unlock(&phydev->lock);
+
+       return ret;
+}
+
+static int linkstate_get_sqi_max(struct net_device *dev)
+{
+       struct phy_device *phydev = dev->phydev;
+       int ret;
+
+       if (!phydev)
+               return -EOPNOTSUPP;
+
+       mutex_lock(&phydev->lock);
+       if (!phydev->drv || !phydev->drv->get_sqi_max)
+               ret = -EOPNOTSUPP;
+       else
+               ret = phydev->drv->get_sqi_max(phydev);
+       mutex_unlock(&phydev->lock);
+
+       return ret;
+}
+
 static int linkstate_prepare_data(const struct ethnl_req_info *req_base,
                                  struct ethnl_reply_data *reply_base,
                                  struct genl_info *info)
@@ -34,6 +75,19 @@ static int linkstate_prepare_data(const struct ethnl_req_info *req_base,
        if (ret < 0)
                return ret;
        data->link = __ethtool_get_link(dev);
+
+       ret = linkstate_get_sqi(dev);
+       if (ret < 0 && ret != -EOPNOTSUPP)
+               return ret;
+
+       data->sqi = ret;
+
+       ret = linkstate_get_sqi_max(dev);
+       if (ret < 0 && ret != -EOPNOTSUPP)
+               return ret;
+
+       data->sqi_max = ret;
+
        ethnl_ops_complete(dev);
 
        return 0;
@@ -42,8 +96,19 @@ static int linkstate_prepare_data(const struct ethnl_req_info *req_base,
 static int linkstate_reply_size(const struct ethnl_req_info *req_base,
                                const struct ethnl_reply_data *reply_base)
 {
-       return nla_total_size(sizeof(u8)) /* LINKSTATE_LINK */
+       struct linkstate_reply_data *data = LINKSTATE_REPDATA(reply_base);
+       int len;
+
+       len = nla_total_size(sizeof(u8)) /* LINKSTATE_LINK */
                + 0;
+
+       if (data->sqi != -EOPNOTSUPP)
+               len += nla_total_size(sizeof(u32));
+
+       if (data->sqi_max != -EOPNOTSUPP)
+               len += nla_total_size(sizeof(u32));
+
+       return len;
 }
 
 static int linkstate_fill_reply(struct sk_buff *skb,
@@ -56,6 +121,14 @@ static int linkstate_fill_reply(struct sk_buff *skb,
            nla_put_u8(skb, ETHTOOL_A_LINKSTATE_LINK, !!data->link))
                return -EMSGSIZE;
 
+       if (data->sqi != -EOPNOTSUPP &&
+           nla_put_u32(skb, ETHTOOL_A_LINKSTATE_SQI, data->sqi))
+               return -EMSGSIZE;
+
+       if (data->sqi_max != -EOPNOTSUPP &&
+           nla_put_u32(skb, ETHTOOL_A_LINKSTATE_SQI_MAX, data->sqi_max))
+               return -EMSGSIZE;
+
        return 0;
 }