From 565020aaeebfa7c8b3ec077bee38f4c15acc9905 Mon Sep 17 00:00:00 2001 From: Jose Abreu Date: Wed, 18 Apr 2018 10:57:55 +0100 Subject: [PATCH] net: stmmac: Disable ACS Feature for GMAC >= 4 ACS Feature is currently enabled for GMAC >= 4 but the llc_snap status is never checked in descriptor rx_status callback. This will cause stmmac to always strip packets even that ACS feature is already stripping them. Lets be safe and disable the ACS feature for GMAC >= 4 and always strip the packets for this GMAC version. Fixes: 477286b53f55 ("stmmac: add GMAC4 core support") Signed-off-by: Jose Abreu Cc: David S. Miller Cc: Joao Pinto Cc: Giuseppe Cavallaro Cc: Alexandre Torgue Signed-off-by: David S. Miller --- drivers/net/ethernet/stmicro/stmmac/dwmac4.h | 2 +- drivers/net/ethernet/stmicro/stmmac/dwmac4_core.c | 7 ------- drivers/net/ethernet/stmicro/stmmac/stmmac_main.c | 7 ++++++- 3 files changed, 7 insertions(+), 9 deletions(-) diff --git a/drivers/net/ethernet/stmicro/stmmac/dwmac4.h b/drivers/net/ethernet/stmicro/stmmac/dwmac4.h index c7bff596c665..dedd40613090 100644 --- a/drivers/net/ethernet/stmicro/stmmac/dwmac4.h +++ b/drivers/net/ethernet/stmicro/stmmac/dwmac4.h @@ -347,7 +347,7 @@ enum power_event { #define MTL_RX_OVERFLOW_INT BIT(16) /* Default operating mode of the MAC */ -#define GMAC_CORE_INIT (GMAC_CONFIG_JD | GMAC_CONFIG_PS | GMAC_CONFIG_ACS | \ +#define GMAC_CORE_INIT (GMAC_CONFIG_JD | GMAC_CONFIG_PS | \ GMAC_CONFIG_BE | GMAC_CONFIG_DCRS) /* To dump the core regs excluding the Address Registers */ diff --git a/drivers/net/ethernet/stmicro/stmmac/dwmac4_core.c b/drivers/net/ethernet/stmicro/stmmac/dwmac4_core.c index a3af92ebbca8..517b1f6736a8 100644 --- a/drivers/net/ethernet/stmicro/stmmac/dwmac4_core.c +++ b/drivers/net/ethernet/stmicro/stmmac/dwmac4_core.c @@ -31,13 +31,6 @@ static void dwmac4_core_init(struct mac_device_info *hw, value |= GMAC_CORE_INIT; - /* Clear ACS bit because Ethernet switch tagging formats such as - * Broadcom tags can look like invalid LLC/SNAP packets and cause the - * hardware to truncate packets on reception. - */ - if (netdev_uses_dsa(dev)) - value &= ~GMAC_CONFIG_ACS; - if (mtu > 1500) value |= GMAC_CONFIG_2K; if (mtu > 2000) diff --git a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c index 9a16931ce39d..b65e2d144698 100644 --- a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c +++ b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c @@ -3495,8 +3495,13 @@ static int stmmac_rx(struct stmmac_priv *priv, int limit, u32 queue) /* ACS is set; GMAC core strips PAD/FCS for IEEE 802.3 * Type frames (LLC/LLC-SNAP) + * + * llc_snap is never checked in GMAC >= 4, so this ACS + * feature is always disabled and packets need to be + * stripped manually. */ - if (unlikely(status != llc_snap)) + if (unlikely(priv->synopsys_id >= DWMAC_CORE_4_00) || + unlikely(status != llc_snap)) frame_len -= ETH_FCS_LEN; if (netif_msg_rx_status(priv)) { -- 2.30.2