From 57e81d44b0e1aa4dcb479ff8de8fc34cf635d0e8 Mon Sep 17 00:00:00 2001 From: Sunil Goutham Date: Tue, 30 Aug 2016 11:36:26 +0530 Subject: [PATCH] net: thunderx: Fix for HW issue while padding TSO packet There is a issue in HW where-in while sending GSO sized pkts as part of TSO, if pkt len falls below configured min packet size i.e 60, NIC will zero PAD packet and also updates IP total length. Hence set this value to lessthan min pkt size of MAC + IP + TCP headers, BGX will anyway do the padding to transmit 64 byte pkt including FCS. Signed-off-by: Sunil Goutham Signed-off-by: David S. Miller --- drivers/net/ethernet/cavium/thunder/nic_main.c | 11 ++++++++--- 1 file changed, 8 insertions(+), 3 deletions(-) diff --git a/drivers/net/ethernet/cavium/thunder/nic_main.c b/drivers/net/ethernet/cavium/thunder/nic_main.c index 16ed20357c5c..85cc782b9060 100644 --- a/drivers/net/ethernet/cavium/thunder/nic_main.c +++ b/drivers/net/ethernet/cavium/thunder/nic_main.c @@ -251,9 +251,14 @@ static void nic_set_tx_pkt_pad(struct nicpf *nic, int size) int lmac; u64 lmac_cfg; - /* Max value that can be set is 60 */ - if (size > 60) - size = 60; + /* There is a issue in HW where-in while sending GSO sized + * pkts as part of TSO, if pkt len falls below this size + * NIC will zero PAD packet and also updates IP total length. + * Hence set this value to lessthan min pkt size of MAC+IP+TCP + * headers, BGX will do the padding to transmit 64 byte pkt. + */ + if (size > 52) + size = 52; for (lmac = 0; lmac < (MAX_BGX_PER_CN88XX * MAX_LMAC_PER_BGX); lmac++) { lmac_cfg = nic_reg_read(nic, NIC_PF_LMAC_0_7_CFG | (lmac << 3)); -- 2.20.1