Messages in this thread Patch in this message | | | Date | Tue, 19 Apr 2011 13:08:29 -0700 | From | Greg KH <> | Subject | [20/70] gianfar: Fall back to software tcp/udp checksum on older controllers |
| |
2.6.38-stable review patch. If anyone has any objections, please let us know.
------------------
From: Alex Dubov <oakad@yahoo.com>
[ Upstream commit 4363c2fddb1399b728ef21ee8101c148a311ea45 ]
As specified by errata eTSEC49 of MPC8548 and errata eTSEC12 of MPC83xx, older revisions of gianfar controllers will be unable to calculate a TCP/UDP packet checksum for some alignments of the appropriate FCB. This patch checks for FCB alignment on such controllers and falls back to software checksumming if the alignment is known to be bad.
Signed-off-by: Alex Dubov <oakad@yahoo.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de> --- drivers/net/gianfar.c | 16 ++++++++++++++-- drivers/net/gianfar.h | 1 + 2 files changed, 15 insertions(+), 2 deletions(-)
--- a/drivers/net/gianfar.c +++ b/drivers/net/gianfar.c @@ -950,6 +950,11 @@ static void gfar_detect_errata(struct gf (pvr == 0x80861010 && (mod & 0xfff9) == 0x80c0)) priv->errata |= GFAR_ERRATA_A002; + /* MPC8313 Rev < 2.0, MPC8548 rev 2.0 */ + if ((pvr == 0x80850010 && mod == 0x80b0 && rev < 0x0020) || + (pvr == 0x80210020 && mod == 0x8030 && rev == 0x0020)) + priv->errata |= GFAR_ERRATA_12; + if (priv->errata) dev_info(dev, "enabled errata workarounds, flags: 0x%x\n", priv->errata); @@ -2156,8 +2161,15 @@ static int gfar_start_xmit(struct sk_buf /* Set up checksumming */ if (CHECKSUM_PARTIAL == skb->ip_summed) { fcb = gfar_add_fcb(skb); - lstatus |= BD_LFLAG(TXBD_TOE); - gfar_tx_checksum(skb, fcb); + /* as specified by errata */ + if (unlikely(gfar_has_errata(priv, GFAR_ERRATA_12) + && ((unsigned long)fcb % 0x20) > 0x18)) { + __skb_pull(skb, GMAC_FCB_LEN); + skb_checksum_help(skb); + } else { + lstatus |= BD_LFLAG(TXBD_TOE); + gfar_tx_checksum(skb, fcb); + } } if (vlan_tx_tag_present(skb)) { --- a/drivers/net/gianfar.h +++ b/drivers/net/gianfar.h @@ -1039,6 +1039,7 @@ enum gfar_errata { GFAR_ERRATA_74 = 0x01, GFAR_ERRATA_76 = 0x02, GFAR_ERRATA_A002 = 0x04, + GFAR_ERRATA_12 = 0x08, /* a.k.a errata eTSEC49 */ }; /* Struct stolen almost completely (and shamelessly) from the FCC enet source
| |