From 89760ddf20a392c353d44c7962b3e891d2401df6 Mon Sep 17 00:00:00 2001
From: bluhm <bluhm@openbsd.org>
Date: Thu, 10 Feb 2022 16:22:00 +0000
Subject: [PATCH] Enable receive checksum offloading on ixl(4) network
 interfaces. from jan@; test and OK dlg@

---
 sys/dev/pci/if_ixl.c | 21 ++++++++++++++++++++-
 1 file changed, 20 insertions(+), 1 deletion(-)

diff --git a/sys/dev/pci/if_ixl.c b/sys/dev/pci/if_ixl.c
index 71dff53d323..6412e5a0760 100644
--- a/sys/dev/pci/if_ixl.c
+++ b/sys/dev/pci/if_ixl.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: if_ixl.c,v 1.81 2022/02/09 11:12:21 dlg Exp $ */
+/*	$OpenBSD: if_ixl.c,v 1.82 2022/02/10 16:22:00 bluhm Exp $ */
 
 /*
  * Copyright (c) 2013-2015, Intel Corporation
@@ -1399,6 +1399,7 @@ static int	ixl_rxeof(struct ixl_softc *, struct ixl_rx_ring *);
 static void	ixl_rxfill(struct ixl_softc *, struct ixl_rx_ring *);
 static void	ixl_rxrefill(void *);
 static int	ixl_rxrinfo(struct ixl_softc *, struct if_rxrinfo *);
+static void	ixl_rx_checksum(struct mbuf *, uint64_t);
 
 #if NKSTAT > 0
 static void	ixl_kstat_attach(struct ixl_softc *);
@@ -3297,6 +3298,7 @@ ixl_rxeof(struct ixl_softc *sc, struct ixl_rx_ring *rxr)
 					SET(m->m_flags, M_VLANTAG);
 				}
 
+				ixl_rx_checksum(m, word);
 				ml_enqueue(&ml, m);
 			} else {
 				ifp->if_ierrors++; /* XXX */
@@ -3429,6 +3431,23 @@ ixl_rxrinfo(struct ixl_softc *sc, struct if_rxrinfo *ifri)
 	return (rv);
 }
 
+static void
+ixl_rx_checksum(struct mbuf *m, uint64_t word)
+{
+	if (!ISSET(word, IXL_RX_DESC_L3L4P))
+		return;
+
+	if (ISSET(word, IXL_RX_DESC_IPE))
+		return;
+
+	m->m_pkthdr.csum_flags |= M_IPV4_CSUM_IN_OK;
+
+	if (ISSET(word, IXL_RX_DESC_L4E))
+		return;
+
+	m->m_pkthdr.csum_flags |= M_TCP_CSUM_IN_OK | M_UDP_CSUM_IN_OK;
+}
+
 static int
 ixl_intr0(void *xsc)
 {
-- 
2.20.1