Implement and enable IPv4, TCP, and UDP checksum offloading for igc.

ok kevlo@

diff --git a/sys/dev/pci/if_igc.c b/sys/dev/pci/if_igc.c
index b6377fb..734bc8b 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 1.8 2022/05/11 06:14:15 kevlo Exp $        */
+/*     $OpenBSD: if_igc.c,v 1.9 2022/06/02 07:41:17 mbuhl Exp $        */
 /*-
  * SPDX-License-Identifier: BSD-2-Clause
  *
@@ -48,6 +48,8 @@
 
 #include <netinet/in.h>
 #include <netinet/if_ether.h>
+#include <netinet/ip.h>
+#include <netinet/ip6.h>
 
 #if NBPFILTER > 0
 #include <net/bpf.h>
@@ -115,6 +117,7 @@ int igc_media_change(struct ifnet *);
 void   igc_iff(struct igc_softc *);
 void   igc_update_link_status(struct igc_softc *);
 int    igc_get_buf(struct rx_ring *, int);
+int    igc_tx_ctx_setup(struct tx_ring *, struct mbuf *, int, uint32_t *);
 
 void   igc_configure_queues(struct igc_softc *);
 void   igc_set_queues(struct igc_softc *, uint32_t, uint32_t, int);
@@ -790,10 +793,12 @@ igc_setup_interface(struct igc_softc *sc)
 #ifdef notyet
 #if NVLAN > 0
        ifp->if_capabilities |= IFCAP_VLAN_HWTAGGING;
+#endif
 #endif
 
+       ifp->if_capabilities |= IFCAP_CSUM_IPv4;
        ifp->if_capabilities |= IFCAP_CSUM_TCPv4 | IFCAP_CSUM_UDPv4;
-#endif
+       ifp->if_capabilities |= IFCAP_CSUM_TCPv6 | IFCAP_CSUM_UDPv6;
 
        /* Initialize ifmedia structures. */
        ifmedia_init(&sc->media, IFM_IMASK, igc_media_change, igc_media_status);
@@ -996,6 +1001,12 @@ igc_start(struct ifqueue *ifq)
                bus_dmamap_sync(txr->txdma.dma_tag, map, 0,
                    map->dm_mapsize, BUS_DMASYNC_PREWRITE);
 
+               if (igc_tx_ctx_setup(txr, m, prod, &olinfo_status)) {
+                       /* Consume the first descriptor */
+                       prod++;
+                       prod &= mask;
+               }
+
                for (i = 0; i < map->dm_nsegs; i++) {
                        txdesc = &txr->tx_base[prod];
 
@@ -1979,6 +1990,117 @@ igc_free_transmit_buffers(struct tx_ring *txr)
        txr->txtag = NULL;
 }
 
+
+/*********************************************************************
+ *
+ *  Advanced Context Descriptor setup for VLAN, CSUM or TSO
+ *
+ **********************************************************************/
+
+int
+igc_tx_ctx_setup(struct tx_ring *txr, struct mbuf *mp, int prod,
+    uint32_t *olinfo_status)
+{
+       struct igc_adv_tx_context_desc *txdesc;
+       struct ether_header *eh = mtod(mp, struct ether_header *);
+       struct mbuf *m;
+       uint32_t type_tucmd_mlhl = 0;
+       uint32_t vlan_macip_lens = 0;
+       uint32_t iphlen;
+       int hoff;
+       int off = 0;
+       uint8_t ipproto;
+
+       vlan_macip_lens |= (sizeof(*eh) << IGC_ADVTXD_MACLEN_SHIFT);
+
+       /*
+        * In advanced descriptors the vlan tag must
+        * be placed into the context descriptor. Hence
+        * we need to make one even if not doing offloads.
+        */
+#ifdef notyet
+#if NVLAN > 0
+       if (ISSET(mp->m_flags, M_VLANTAG)) {
+               uint32_t vtag = mp->m_pkthdr.ether_vtag;
+               vlan_macip_lens |= (vtag << IGC_ADVTXD_VLAN_SHIFT);
+               off = 1;
+       }
+#endif
+#endif
+
+       switch (ntohs(eh->ether_type)) {
+       case ETHERTYPE_IP: {
+               struct ip *ip;
+
+               m = m_getptr(mp, sizeof(*eh), &hoff);
+               KASSERT(m != NULL && m->m_len - hoff >= sizeof(*ip));
+               ip = (struct ip *)(mtod(m, caddr_t) + hoff);
+
+               iphlen = ip->ip_hl << 2;
+               ipproto = ip->ip_p;
+
+               type_tucmd_mlhl |= IGC_ADVTXD_TUCMD_IPV4;
+               if (ISSET(mp->m_pkthdr.csum_flags, M_IPV4_CSUM_OUT)) {
+                       *olinfo_status |= IGC_TXD_POPTS_IXSM << 8;
+                       off = 1;
+               }
+
+               break;
+       }
+#ifdef INET6
+       case ETHERTYPE_IPV6: {
+               struct ip6_hdr *ip6;
+
+               m = m_getptr(mp, sizeof(*eh), &hoff);
+               KASSERT(m != NULL && m->m_len - hoff >= sizeof(*ip6));
+               ip6 = (struct ip6_hdr *)(mtod(m, caddr_t) + hoff);
+
+               iphlen = sizeof(*ip6);
+               ipproto = ip6->ip6_nxt;
+
+               type_tucmd_mlhl |= IGC_ADVTXD_TUCMD_IPV6;
+               break;
+       }
+#endif
+       default:
+               return 0;
+       }
+
+       vlan_macip_lens |= iphlen;
+       type_tucmd_mlhl |= IGC_ADVTXD_DCMD_DEXT | IGC_ADVTXD_DTYP_CTXT;
+
+       switch (ipproto) {
+       case IPPROTO_TCP:
+               type_tucmd_mlhl |= IGC_ADVTXD_TUCMD_L4T_TCP;
+               if (ISSET(mp->m_pkthdr.csum_flags, M_TCP_CSUM_OUT)) {
+                       *olinfo_status |= IGC_TXD_POPTS_TXSM << 8;
+                       off = 1;
+               }
+               break;
+       case IPPROTO_UDP:
+               type_tucmd_mlhl |= IGC_ADVTXD_TUCMD_L4T_UDP;
+               if (ISSET(mp->m_pkthdr.csum_flags, M_UDP_CSUM_OUT)) {
+                       *olinfo_status |= IGC_TXD_POPTS_TXSM << 8;
+                       off = 1;
+               }
+               break;
+       }
+
+       if (off == 0)
+               return 0;
+
+       /* Now ready a context descriptor */
+       txdesc = (struct igc_adv_tx_context_desc *)&txr->tx_base[prod];
+
+       /* Now copy bits into descriptor */
+       htolem32(&txdesc->vlan_macip_lens, vlan_macip_lens);
+       htolem32(&txdesc->type_tucmd_mlhl, type_tucmd_mlhl);
+       htolem32(&txdesc->seqnum_seed, 0);
+       htolem32(&txdesc->mss_l4len_idx, 0);
+
+       return 1;
+}
+
 /*********************************************************************
  *
  *  Allocate memory for rx_buffer structures. Since we use one