From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from web37605.mail.mud.yahoo.com (web37605.mail.mud.yahoo.com [209.191.87.88]) by ozlabs.org (Postfix) with SMTP id E51151007D2 for ; Thu, 27 Jan 2011 19:14:24 +1100 (EST) Message-ID: <468529.34173.qm@web37605.mail.mud.yahoo.com> Date: Thu, 27 Jan 2011 00:14:21 -0800 (PST) From: Alex Dubov Subject: [PATCH] gianfar: Fall back to software tcp/udp checksum on older controllers To: mlcreech@gmail.com MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Cc: linuxppc-dev@lists.ozlabs.org, davem@davemloft.net List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , As specified by errata eTSEC49 of MPC8548 and errata eTSEC12 of MPC83xx,=0A= older revisions of gianfar controllers will be unable to calculate a TCP/UD= P=0Apacket checksum for some aligments of the appropriate FCB. This patch c= hecks=0Afor FCB alignment on such controllers and falls back to software ch= ecksumming=0Aif the aligment is known to be bad.=0A=0ASigned-off-by: Alex D= ubov =0A---=0AThis is my, somewhat different approach to M= atthew Creech proposed solution.=0A=0A drivers/net/gianfar.c | 21 +++++++= ++++++++++++--=0A drivers/net/gianfar.h | 1 +=0A 2 files changed, 20 ins= ertions(+), 2 deletions(-)=0A=0Adiff --git a/drivers/net/gianfar.c b/driver= s/net/gianfar.c=0Aindex 5ed8f9f..b4f0e99 100644=0A--- a/drivers/net/gianfar= .c=0A+++ b/drivers/net/gianfar.c=0A@@ -950,6 +950,11 @@ static void gfar_de= tect_errata(struct gfar_private *priv)=0A =09=09=09(pvr =3D=3D 0x80861010 &= & (mod & 0xfff9) =3D=3D 0x80c0))=0A =09=09priv->errata |=3D GFAR_ERRATA_A00= 2;=0A =0A+=09/* MPC8313 Rev < 2.0, MPC8548 rev 2.0 */=0A+=09if ((pvr =3D=3D= 0x80850010 && mod =3D=3D 0x80b0 && rev < 0x0020)=0A+=09 || (pvr =3D=3D = 0x80210020 && mod =3D=3D 0x8030 && rev =3D=3D 0x0020))=0A+=09=09priv->errat= a |=3D GFAR_ERRATA_12;=0A+=0A =09if (priv->errata)=0A =09=09dev_info(dev, "= enabled errata workarounds, flags: 0x%x\n",=0A =09=09=09 priv->errata);=0A@= @ -2156,8 +2161,20 @@ static int gfar_start_xmit(struct sk_buff *skb, struc= t net_device *dev)=0A =09/* Set up checksumming */=0A =09if (CHECKSUM_PARTI= AL =3D=3D skb->ip_summed) {=0A =09=09fcb =3D gfar_add_fcb(skb);=0A-=09=09ls= tatus |=3D BD_LFLAG(TXBD_TOE);=0A-=09=09gfar_tx_checksum(skb, fcb);=0A+=09= =09switch (unlikely(gfar_has_errata(priv, GFAR_ERRATA_12))=0A+=09=09=09? 1 = : 0) {=0A+=09=09case 1:=0A+=09=09=09/* as specified by errata */=0A+=09=09= =09if (((unsigned long)fcb % 0x20) > 0x18) { =0A+=09=09=09=09__skb_pull(skb= , GMAC_FCB_LEN);=0A+=09=09=09=09skb_checksum_help(skb);=0A+=09=09=09=09brea= k;=0A+=09=09=09}=0A+=09=09=09/* otherwise, fall through */=0A+=09=09default= :=0A+=09=09=09lstatus |=3D BD_LFLAG(TXBD_TOE);=0A+=09=09=09gfar_tx_checksum= (skb, fcb);=0A+=09=09}=0A =09}=0A =0A =09if (vlan_tx_tag_present(skb)) {=0A= diff --git a/drivers/net/gianfar.h b/drivers/net/gianfar.h=0Aindex 54de413.= .ec5d595 100644=0A--- a/drivers/net/gianfar.h=0A+++ b/drivers/net/gianfar.h= =0A@@ -1039,6 +1039,7 @@ enum gfar_errata {=0A =09GFAR_ERRATA_74=09=09=3D 0= x01,=0A =09GFAR_ERRATA_76=09=09=3D 0x02,=0A =09GFAR_ERRATA_A002=09=3D 0x04,= =0A+=09GFAR_ERRATA_12=09=09=3D 0x08, /* a.k.a errata eTSEC49 */=0A };=0A = =0A /* Struct stolen almost completely (and shamelessly) from the FCC enet = source=0A-- =0A1.7.3.2=0A=0A=0A=0A=0A