4.14-stable review patch. If anyone has any objections, please let me know.
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From: Jose Abreu Jose.Abreu@synopsys.com
commit 565020aaeebfa7c8b3ec077bee38f4c15acc9905 upstream.
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 joabreu@synopsys.com Cc: David S. Miller davem@davemloft.net Cc: Joao Pinto jpinto@synopsys.com Cc: Giuseppe Cavallaro peppe.cavallaro@st.com Cc: Alexandre Torgue alexandre.torgue@st.com Signed-off-by: David S. Miller davem@davemloft.net Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org
--- 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(-)
--- a/drivers/net/ethernet/stmicro/stmmac/dwmac4.h +++ b/drivers/net/ethernet/stmicro/stmmac/dwmac4.h @@ -336,7 +336,7 @@ 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 */ --- a/drivers/net/ethernet/stmicro/stmmac/dwmac4_core.c +++ b/drivers/net/ethernet/stmicro/stmmac/dwmac4_core.c @@ -30,13 +30,6 @@ static void dwmac4_core_init(struct mac_
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) --- a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c +++ b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c @@ -3415,8 +3415,13 @@ static int stmmac_rx(struct stmmac_priv
/* 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)) {