Change default duplex setting and simplify the setup of srrctl.BSIZEPKT.

During media selection through ifconfig one might not specify the duplex
setting through the mediaopt flag.  In that case the igc(4) would default
to full-duplex.  The problem with this approach is that em(4) defaults to
half-duplex.  Because of that if one connects both NICs and sets media to
e.g. 100baseTX on both of them no carrier will be found.
Fix that by matching igc(4) behaviour with what em(4) does.

Adapted from FreeBSD commits 3b8d04f845b416d29a258658b8a48d1afb4a2e81 and
0eb8cd1de26849cbaefaf3bc59aa9612fa0dfa52 respectively.

ok mbuhl@

diff --git a/sys/dev/pci/if_igc.c b/sys/dev/pci/if_igc.c
index c39121a..5deb53d 100644 (file)
--- a/sys/dev/pci/if_igc.c
+++ b/sys/dev/pci/if_igc.c
@@ -1,4 +1,4 @@
-/*     $OpenBSD: if_igc.c,v 1.14 2023/11/10 15:51:20 bluhm Exp $       */
+/*     $OpenBSD: if_igc.c,v 1.15 2024/01/23 08:48:12 kevlo Exp $       */
 /*-
  * SPDX-License-Identifier: BSD-2-Clause
  *
@@ -1523,16 +1523,16 @@ igc_media_change(struct ifnet *ifp)
                sc->hw.phy.autoneg_advertised = ADVERTISE_1000_FULL;
                break;
        case IFM_100_TX:
-               if ((ifm->ifm_media & IFM_GMASK) == IFM_HDX)
-                       sc->hw.phy.autoneg_advertised = ADVERTISE_100_HALF;
-               else
+               if ((ifm->ifm_media & IFM_GMASK) == IFM_FDX)
                        sc->hw.phy.autoneg_advertised = ADVERTISE_100_FULL;
+               else
+                       sc->hw.phy.autoneg_advertised = ADVERTISE_100_HALF;
                break;
        case IFM_10_T:
-               if ((ifm->ifm_media & IFM_GMASK) == IFM_HDX)
-                       sc->hw.phy.autoneg_advertised = ADVERTISE_10_HALF;
-               else
+               if ((ifm->ifm_media & IFM_GMASK) == IFM_FDX)
                        sc->hw.phy.autoneg_advertised = ADVERTISE_10_FULL;
+               else
+                       sc->hw.phy.autoneg_advertised = ADVERTISE_10_HALF;
                break;
        default:
                return EINVAL;
@@ -2179,6 +2179,8 @@ igc_setup_receive_ring(struct rx_ring *rxr)
  *  Enable receive unit.
  *
  **********************************************************************/
+#define BSIZEPKT_ROUNDUP       ((1 << IGC_SRRCTL_BSIZEPKT_SHIFT) - 1)
+
 void
 igc_initialize_receive_unit(struct igc_softc *sc)
 {
@@ -2226,12 +2228,10 @@ igc_initialize_receive_unit(struct igc_softc *sc)
        if (sc->sc_nqueues > 1)
                igc_initialize_rss_mapping(sc);
 
-#if 0
-       srrctl |= 4096 >> IGC_SRRCTL_BSIZEPKT_SHIFT;
-       rctl |= IGC_RCTL_SZ_4096 | IGC_RCTL_BSEX;
-#endif
-
-       srrctl |= 2048 >> IGC_SRRCTL_BSIZEPKT_SHIFT;
+       /* Set maximum packet buffer len */
+       srrctl |= (sc->rx_mbuf_sz + BSIZEPKT_ROUNDUP) >>
+           IGC_SRRCTL_BSIZEPKT_SHIFT;
+       /* srrctl above overrides this but set the register to a sane value */
        rctl |= IGC_RCTL_SZ_2048;
 
        /*