net: spacemit: Remove broken flow control support

The current flow control implementation doesn't handle autonegotiation
and ethtool operations properly. Remove it for now so we don't claim
support for something that doesn't really work. A better implementation
will be sent in future patches.

Signed-off-by: Vivian Wang <wangruikang@iscas.ac.cn>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Link: https://patch.msgid.link/20260104-k1-ethernet-actually-remove-fc-v3-1-3871b055064c@iscas.ac.cn
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

diff --git a/drivers/net/ethernet/spacemit/k1_emac.c b/drivers/net/ethernet/spacemit/k1_emac.c
index 220eb5ce75833d9f345be7f68347e358f879e9e4..c85dc742c404df23713f0a49e10b333fb15034b5 100644 (file)
--- a/drivers/net/ethernet/spacemit/k1_emac.c
+++ b/drivers/net/ethernet/spacemit/k1_emac.c
@@ -46,8 +46,6 @@
 #define EMAC_RX_FRAMES                 64
 #define EMAC_RX_COAL_TIMEOUT           (600 * 312)
 
-#define DEFAULT_FC_PAUSE_TIME          0xffff
-#define DEFAULT_FC_FIFO_HIGH           1600
 #define DEFAULT_TX_ALMOST_FULL         0x1f8
 #define DEFAULT_TX_THRESHOLD           1518
 #define DEFAULT_RX_THRESHOLD           12
@@ -132,9 +130,6 @@ struct emac_priv {
        u32 tx_delay;
        u32 rx_delay;
 
-       bool flow_control_autoneg;
-       u8 flow_control;
-
        /* Softirq-safe, hold while touching hardware statistics */
        spinlock_t stats_lock;
 };
@@ -179,9 +174,7 @@ static void emac_set_mac_addr_reg(struct emac_priv *priv,
 
 static void emac_set_mac_addr(struct emac_priv *priv, const unsigned char *addr)
 {
-       /* We use only one address, so set the same for flow control as well */
        emac_set_mac_addr_reg(priv, addr, MAC_ADDRESS1_HIGH);
-       emac_set_mac_addr_reg(priv, addr, MAC_FC_SOURCE_ADDRESS_HIGH);
 }
 
 static void emac_reset_hw(struct emac_priv *priv)
@@ -200,9 +193,6 @@ static void emac_reset_hw(struct emac_priv *priv)
 
 static void emac_init_hw(struct emac_priv *priv)
 {
-       /* Destination address for 802.3x Ethernet flow control */
-       u8 fc_dest_addr[ETH_ALEN] = { 0x01, 0x80, 0xc2, 0x00, 0x00, 0x01 };
-
        u32 rxirq = 0, dma = 0;
 
        regmap_set_bits(priv->regmap_apmu,
@@ -228,12 +218,6 @@ static void emac_init_hw(struct emac_priv *priv)
                DEFAULT_TX_THRESHOLD);
        emac_wr(priv, MAC_RECEIVE_PACKET_START_THRESHOLD, DEFAULT_RX_THRESHOLD);
 
-       /* Configure flow control (enabled in emac_adjust_link() later) */
-       emac_set_mac_addr_reg(priv, fc_dest_addr, MAC_FC_SOURCE_ADDRESS_HIGH);
-       emac_wr(priv, MAC_FC_PAUSE_HIGH_THRESHOLD, DEFAULT_FC_FIFO_HIGH);
-       emac_wr(priv, MAC_FC_HIGH_PAUSE_TIME, DEFAULT_FC_PAUSE_TIME);
-       emac_wr(priv, MAC_FC_PAUSE_LOW_THRESHOLD, 0);
-
        /* RX IRQ mitigation */
        rxirq = FIELD_PREP(MREGBIT_RECEIVE_IRQ_FRAME_COUNTER_MASK,
                           EMAC_RX_FRAMES);
@@ -1018,57 +1002,6 @@ static int emac_mdio_init(struct emac_priv *priv)
        return ret;
 }
 
-static void emac_set_tx_fc(struct emac_priv *priv, bool enable)
-{
-       u32 val;
-
-       val = emac_rd(priv, MAC_FC_CONTROL);
-
-       FIELD_MODIFY(MREGBIT_FC_GENERATION_ENABLE, &val, enable);
-       FIELD_MODIFY(MREGBIT_AUTO_FC_GENERATION_ENABLE, &val, enable);
-
-       emac_wr(priv, MAC_FC_CONTROL, val);
-}
-
-static void emac_set_rx_fc(struct emac_priv *priv, bool enable)
-{
-       u32 val = emac_rd(priv, MAC_FC_CONTROL);
-
-       FIELD_MODIFY(MREGBIT_FC_DECODE_ENABLE, &val, enable);
-
-       emac_wr(priv, MAC_FC_CONTROL, val);
-}
-
-static void emac_set_fc(struct emac_priv *priv, u8 fc)
-{
-       emac_set_tx_fc(priv, fc & FLOW_CTRL_TX);
-       emac_set_rx_fc(priv, fc & FLOW_CTRL_RX);
-       priv->flow_control = fc;
-}
-
-static void emac_set_fc_autoneg(struct emac_priv *priv)
-{
-       struct phy_device *phydev = priv->ndev->phydev;
-       u32 local_adv, remote_adv;
-       u8 fc;
-
-       local_adv = linkmode_adv_to_lcl_adv_t(phydev->advertising);
-
-       remote_adv = 0;
-
-       if (phydev->pause)
-               remote_adv |= LPA_PAUSE_CAP;
-
-       if (phydev->asym_pause)
-               remote_adv |= LPA_PAUSE_ASYM;
-
-       fc = mii_resolve_flowctrl_fdx(local_adv, remote_adv);
-
-       priv->flow_control_autoneg = true;
-
-       emac_set_fc(priv, fc);
-}
-
 /*
  * Even though this MAC supports gigabit operation, it only provides 32-bit
  * statistics counters. The most overflow-prone counters are the "bytes" ones,
@@ -1425,42 +1358,6 @@ static void emac_ethtool_get_regs(struct net_device *dev,
                        emac_rd(priv, MAC_GLOBAL_CONTROL + i * 4);
 }
 
-static void emac_get_pauseparam(struct net_device *dev,
-                               struct ethtool_pauseparam *pause)
-{
-       struct emac_priv *priv = netdev_priv(dev);
-
-       pause->autoneg = priv->flow_control_autoneg;
-       pause->tx_pause = !!(priv->flow_control & FLOW_CTRL_TX);
-       pause->rx_pause = !!(priv->flow_control & FLOW_CTRL_RX);
-}
-
-static int emac_set_pauseparam(struct net_device *dev,
-                              struct ethtool_pauseparam *pause)
-{
-       struct emac_priv *priv = netdev_priv(dev);
-       u8 fc = 0;
-
-       if (!netif_running(dev))
-               return -ENETDOWN;
-
-       priv->flow_control_autoneg = pause->autoneg;
-
-       if (pause->autoneg) {
-               emac_set_fc_autoneg(priv);
-       } else {
-               if (pause->tx_pause)
-                       fc |= FLOW_CTRL_TX;
-
-               if (pause->rx_pause)
-                       fc |= FLOW_CTRL_RX;
-
-               emac_set_fc(priv, fc);
-       }
-
-       return 0;
-}
-
 static void emac_get_drvinfo(struct net_device *dev,
                             struct ethtool_drvinfo *info)
 {
@@ -1634,8 +1531,6 @@ static void emac_adjust_link(struct net_device *dev)
                }
 
                emac_wr(priv, MAC_GLOBAL_CONTROL, ctrl);
-
-               emac_set_fc_autoneg(priv);
        }
 
        phy_print_status(phydev);
@@ -1715,8 +1610,6 @@ static int emac_phy_connect(struct net_device *ndev)
                goto err_node_put;
        }
 
-       phy_support_asym_pause(phydev);
-
        phydev->mac_managed_pm = true;
 
        emac_update_delay_line(priv);
@@ -1886,9 +1779,6 @@ static const struct ethtool_ops emac_ethtool_ops = {
        .get_sset_count         = emac_get_sset_count,
        .get_strings            = emac_get_strings,
        .get_ethtool_stats      = emac_get_ethtool_stats,
-
-       .get_pauseparam         = emac_get_pauseparam,
-       .set_pauseparam         = emac_set_pauseparam,
 };
 
 static const struct net_device_ops emac_netdev_ops = {