Documentation states that TxPBL must be >= 4 to allow TSO support, but the driver doesn't check this. TxPBL comes from the platform glue code or DT. Add a check with a warning if platform glue code attempts to enable TSO support with TxPBL too low. Signed-off-by: Russell King (Oracle) --- drivers/net/ethernet/stmicro/stmmac/stmmac_main.c | 14 ++++++++++++++ 1 file changed, 14 insertions(+) diff --git a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c index 5286ad6412a3..406c32142d90 100644 --- a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c +++ b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c @@ -4388,6 +4388,8 @@ static void stmmac_set_gso_types(struct stmmac_priv *priv, bool tso) static void stmmac_set_gso_features(struct net_device *ndev) { struct stmmac_priv *priv = netdev_priv(ndev); + const struct stmmac_dma_cfg *dma_cfg; + int txpbl; if (!(priv->plat->flags & STMMAC_FLAG_TSO_EN)) return; @@ -4397,6 +4399,18 @@ static void stmmac_set_gso_features(struct net_device *ndev) return; } + /* FIXME: + * STM32MP151 (v4.2 userver v4.0) states that TxPBL must be >= 4. It + * is not clear whether PBLx8 (which multiplies the PBL value by 8) + * influences this. + */ + dma_cfg = priv->plat->dma_cfg; + txpbl = dma_cfg->txpbl ?: dma_cfg->pbl; + if (txpbl < 4) { + dev_warn(priv->device, "txpbl(%d) is too low for TSO\n", txpbl); + return; + } + ndev->hw_features |= NETIF_F_TSO | NETIF_F_TSO6; if (priv->plat->core_type == DWMAC_CORE_GMAC4) ndev->hw_features |= NETIF_F_GSO_UDP_L4; -- 2.47.3