net: marvell: prestera: Add ethtool interface support

The ethtool API provides support for the configuration of the following
features: speed and duplex, auto-negotiation, MDI-x, forward error
correction, port media type. The API also provides information about the
port status, hardware and software statistic. The following limitation
exists:

    - port media type should be configured before speed setting
    - ethtool -m option is not supported
    - ethtool -p option is not supported
    - ethtool -r option is supported for RJ45 port only
    - the following combination of parameters is not supported:

          ethtool -s sw1pX port XX autoneg on

    - forward error correction feature is supported only on SFP ports, 10G
      speed

    - auto-negotiation and MDI-x features are not supported on
      Copper-to-Fiber SFP module

Co-developed-by: Andrii Savka <andrii.savka@plvision.eu>
Signed-off-by: Andrii Savka <andrii.savka@plvision.eu>
Co-developed-by: Serhiy Boiko <serhiy.boiko@plvision.eu>
Signed-off-by: Serhiy Boiko <serhiy.boiko@plvision.eu>
Signed-off-by: Vadym Kochan <vadym.kochan@plvision.eu>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 23 insertions, 5 deletions

diff --git a/drivers/net/ethernet/marvell/prestera/prestera_main.c b/drivers/net/ethernet/marvell/prestera/prestera_main.c
index 47cd2bc367bf..bb51ee5646cd 100644
--- a/drivers/net/ethernet/marvell/prestera/prestera_main.c
+++ b/drivers/net/ethernet/marvell/prestera/prestera_main.c
@@ -13,6 +13,7 @@
 #include "prestera_hw.h"
 #include "prestera_rxtx.h"
 #include "prestera_devlink.h"
+#include "prestera_ethtool.h"
 
 #define PRESTERA_MTU_DEFAULT	1536
 
@@ -190,22 +191,38 @@ static const struct net_device_ops prestera_netdev_ops = {
 	.ndo_get_devlink_port = prestera_devlink_get_port,
 };
 
-static int prestera_port_autoneg_set(struct prestera_port *port, bool enable,
-				     u64 link_modes, u8 fec)
+int prestera_port_autoneg_set(struct prestera_port *port, bool enable,
+			      u64 adver_link_modes, u8 adver_fec)
 {
 	bool refresh = false;
+	u64 link_modes;
 	int err;
+	u8 fec;
 
 	if (port->caps.type != PRESTERA_PORT_TYPE_TP)
 		return enable ? -EINVAL : 0;
 
-	if (port->adver_link_modes != link_modes || port->adver_fec != fec) {
-		port->adver_fec = fec ?: BIT(PRESTERA_PORT_FEC_OFF);
+	if (!enable)
+		goto set_autoneg;
+
+	link_modes = port->caps.supp_link_modes & adver_link_modes;
+	fec = port->caps.supp_fec & adver_fec;
+
+	if (!link_modes && !fec)
+		return -EOPNOTSUPP;
+
+	if (link_modes && port->adver_link_modes != link_modes) {
 		port->adver_link_modes = link_modes;
 		refresh = true;
 	}
 
-	if (port->autoneg == enable && !(port->autoneg && refresh))
+	if (fec && port->adver_fec != fec) {
+		port->adver_fec = fec;
+		refresh = true;
+	}
+
+set_autoneg:
+	if (port->autoneg == enable && !refresh)
 		return 0;
 
 	err = prestera_hw_port_autoneg_set(port, enable, port->adver_link_modes,
@@ -261,6 +278,7 @@ static int prestera_port_create(struct prestera_switch *sw, u32 id)
 
 	dev->features |= NETIF_F_NETNS_LOCAL;
 	dev->netdev_ops = &prestera_netdev_ops;
+	dev->ethtool_ops = &prestera_ethtool_ops;
 
 	netif_carrier_off(dev);