- flow_control &= ~(EFX_FC_RX | EFX_FC_TX | EFX_FC_AUTO);
- flow_control |= pause->rx_pause ? EFX_FC_RX : 0;
- flow_control |= pause->tx_pause ? EFX_FC_TX : 0;
- flow_control |= pause->autoneg ? EFX_FC_AUTO : 0;
+ wanted_fc = ((pause->rx_pause ? EFX_FC_RX : 0) |
+ (pause->tx_pause ? EFX_FC_TX : 0) |
+ (pause->autoneg ? EFX_FC_AUTO : 0));
+
+ if ((wanted_fc & EFX_FC_TX) && !(wanted_fc & EFX_FC_RX)) {
+ EFX_LOG(efx, "Flow control unsupported: tx ON rx OFF\n");
+ return -EINVAL;
+ }
+
+ if (!(efx->phy_op->mmds & DEV_PRESENT_BIT(MDIO_MMD_AN)) &&
+ (wanted_fc & EFX_FC_AUTO)) {
+ EFX_LOG(efx, "PHY does not support flow control "
+ "autonegotiation\n");
+ return -EINVAL;
+ }
+
+ /* TX flow control may automatically turn itself off if the
+ * link partner (intermittently) stops responding to pause
+ * frames. There isn't any indication that this has happened,
+ * so the best we do is leave it up to the user to spot this
+ * and fix it be cycling transmit flow control on this end. */
+ reset = (wanted_fc & EFX_FC_TX) && !(efx->wanted_fc & EFX_FC_TX);
+ if (EFX_WORKAROUND_11482(efx) && reset) {
+ if (falcon_rev(efx) >= FALCON_REV_B0) {
+ /* Recover by resetting the EM block */
+ if (efx->link_up)
+ falcon_drain_tx_fifo(efx);
+ } else {
+ /* Schedule a reset to recover */
+ efx_schedule_reset(efx, RESET_TYPE_INVISIBLE);
+ }
+ }