For proper VLAN packets forwarding CPSW driver uses min tx packet size of
64bytes (VLAN_ETH_ZLEN, excluding ETH_FCS) which was corrected by
commit 9421c9015047 ("net: ethernet: ti: cpsw: fix min eth packet size").Unfortunately, this breaks some industrial automation protocols, as reported by TI customers [1], which can work only with min TX packet size from 60 byte (ecluding FCS). Hence, introduce module boot parameter "tx_packet_min" to allow configure min TX packet size at boot time. [1] https://e2e.ti.com/support/arm/sitara_arm/f/791/t/701669 Fixes: 9421c9015047 ("net: ethernet: ti: cpsw: fix min eth packet size") Signed-off-by: Grygorii Strashko <grygorii.stras...@ti.com> --- drivers/net/ethernet/ti/cpsw.c | 8 ++++++-- 1 file changed, 6 insertions(+), 2 deletions(-) diff --git a/drivers/net/ethernet/ti/cpsw.c b/drivers/net/ethernet/ti/cpsw.c index ceaec56..15d563c 100644 --- a/drivers/net/ethernet/ti/cpsw.c +++ b/drivers/net/ethernet/ti/cpsw.c @@ -188,6 +188,10 @@ static int rx_packet_max = CPSW_MAX_PACKET_SIZE; module_param(rx_packet_max, int, 0); MODULE_PARM_DESC(rx_packet_max, "maximum receive packet size (bytes)"); +static int tx_packet_min = CPSW_MIN_PACKET_SIZE; +module_param(tx_packet_min, int, 0444); +MODULE_PARM_DESC(tx_packet_min, "minimum tx packet size (bytes)"); + static int descs_pool_size = CPSW_CPDMA_DESCS_POOL_SIZE_DEFAULT; module_param(descs_pool_size, int, 0444); MODULE_PARM_DESC(descs_pool_size, "Number of CPDMA CPPI descriptors in pool"); @@ -2131,7 +2135,7 @@ static netdev_tx_t cpsw_ndo_start_xmit(struct sk_buff *skb, struct cpdma_chan *txch; int ret, q_idx; - if (skb_padto(skb, CPSW_MIN_PACKET_SIZE)) { + if (skb_padto(skb, tx_packet_min)) { cpsw_err(priv, tx_err, "packet pad failed\n"); ndev->stats.tx_dropped++; return NET_XMIT_DROP; @@ -3636,7 +3640,7 @@ static int cpsw_probe(struct platform_device *pdev) dma_params.num_chan = data->channels; dma_params.has_soft_reset = true; - dma_params.min_packet_size = CPSW_MIN_PACKET_SIZE; + dma_params.min_packet_size = tx_packet_min; dma_params.desc_mem_size = data->bd_ram_size; dma_params.desc_align = 16; dma_params.has_ext_regs = true; -- 2.10.5
