[PATCH net-next v2] net: stmmac: Fix reception of Broadcom switches tags
Giuseppe CAVALLARO
peppe.cavallaro at st.com
Fri Jan 19 01:53:37 PST 2018
On 1/19/2018 12:12 AM, Florian Fainelli wrote:
> Broadcom tags inserted by Broadcom switches put a 4 byte header after
> the MAC SA and before the EtherType, which may look like some sort of 0
> length LLC/SNAP packet (tcpdump and wireshark do think that way). With
> ACS enabled in stmmac the packets were truncated to 8 bytes on
> reception, whereas clearing this bit allowed normal reception to occur.
>
> In order to make that possible, we need to pass a net_device argument to
> the different core_init() functions and we are dependent on the Broadcom
> tagger padding packets correctly (which it now does). To be as little
> invasive as possible, this is only done for gmac1000 when the network
> device is DSA-enabled (netdev_uses_dsa() returns true).
>
> Signed-off-by: Florian Fainelli <f.fainelli at gmail.com>
Acked-by: Giuseppe Cavallaro <peppe.cavallaro at st.com>
> ---
> Changes in v2:
>
> - fixed build failure in dwmac4_core.c
> - updated dwmac100_core.c to also clear the ASTP bit
>
> drivers/net/ethernet/stmicro/stmmac/common.h | 2 +-
> drivers/net/ethernet/stmicro/stmmac/dwmac-sun8i.c | 3 ++-
> drivers/net/ethernet/stmicro/stmmac/dwmac1000_core.c | 12 +++++++++++-
> drivers/net/ethernet/stmicro/stmmac/dwmac100_core.c | 15 +++++++++++++--
> drivers/net/ethernet/stmicro/stmmac/dwmac4_core.c | 12 +++++++++++-
> drivers/net/ethernet/stmicro/stmmac/stmmac_main.c | 2 +-
> 6 files changed, 39 insertions(+), 7 deletions(-)
>
> diff --git a/drivers/net/ethernet/stmicro/stmmac/common.h b/drivers/net/ethernet/stmicro/stmmac/common.h
> index ce2ea2d491ac..2ffe76c0ff74 100644
> --- a/drivers/net/ethernet/stmicro/stmmac/common.h
> +++ b/drivers/net/ethernet/stmicro/stmmac/common.h
> @@ -474,7 +474,7 @@ struct mac_device_info;
> /* Helpers to program the MAC core */
> struct stmmac_ops {
> /* MAC core initialization */
> - void (*core_init)(struct mac_device_info *hw, int mtu);
> + void (*core_init)(struct mac_device_info *hw, struct net_device *dev);
> /* Enable the MAC RX/TX */
> void (*set_mac)(void __iomem *ioaddr, bool enable);
> /* Enable and verify that the IPC module is supported */
> diff --git a/drivers/net/ethernet/stmicro/stmmac/dwmac-sun8i.c b/drivers/net/ethernet/stmicro/stmmac/dwmac-sun8i.c
> index 9eb7f65d8000..a3fa65b1ca8e 100644
> --- a/drivers/net/ethernet/stmicro/stmmac/dwmac-sun8i.c
> +++ b/drivers/net/ethernet/stmicro/stmmac/dwmac-sun8i.c
> @@ -483,7 +483,8 @@ static int sun8i_dwmac_init(struct platform_device *pdev, void *priv)
> return 0;
> }
>
> -static void sun8i_dwmac_core_init(struct mac_device_info *hw, int mtu)
> +static void sun8i_dwmac_core_init(struct mac_device_info *hw,
> + struct net_device *dev)
> {
> void __iomem *ioaddr = hw->pcsr;
> u32 v;
> diff --git a/drivers/net/ethernet/stmicro/stmmac/dwmac1000_core.c b/drivers/net/ethernet/stmicro/stmmac/dwmac1000_core.c
> index 8a86340ff2d3..540d21786a43 100644
> --- a/drivers/net/ethernet/stmicro/stmmac/dwmac1000_core.c
> +++ b/drivers/net/ethernet/stmicro/stmmac/dwmac1000_core.c
> @@ -25,18 +25,28 @@
> #include <linux/crc32.h>
> #include <linux/slab.h>
> #include <linux/ethtool.h>
> +#include <net/dsa.h>
> #include <asm/io.h>
> #include "stmmac_pcs.h"
> #include "dwmac1000.h"
>
> -static void dwmac1000_core_init(struct mac_device_info *hw, int mtu)
> +static void dwmac1000_core_init(struct mac_device_info *hw,
> + struct net_device *dev)
> {
> void __iomem *ioaddr = hw->pcsr;
> u32 value = readl(ioaddr + GMAC_CONTROL);
> + int mtu = dev->mtu;
>
> /* Configure GMAC core */
> 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_CONTROL_ACS;
> +
> if (mtu > 1500)
> value |= GMAC_CONTROL_2K;
> if (mtu > 2000)
> diff --git a/drivers/net/ethernet/stmicro/stmmac/dwmac100_core.c b/drivers/net/ethernet/stmicro/stmmac/dwmac100_core.c
> index 8ef517356313..91b23f9db31a 100644
> --- a/drivers/net/ethernet/stmicro/stmmac/dwmac100_core.c
> +++ b/drivers/net/ethernet/stmicro/stmmac/dwmac100_core.c
> @@ -25,15 +25,26 @@
> *******************************************************************************/
>
> #include <linux/crc32.h>
> +#include <net/dsa.h>
> #include <asm/io.h>
> #include "dwmac100.h"
>
> -static void dwmac100_core_init(struct mac_device_info *hw, int mtu)
> +static void dwmac100_core_init(struct mac_device_info *hw,
> + struct net_device *dev)
> {
> void __iomem *ioaddr = hw->pcsr;
> u32 value = readl(ioaddr + MAC_CONTROL);
>
> - writel((value | MAC_CORE_INIT), ioaddr + MAC_CONTROL);
> + value |= MAC_CORE_INIT;
> +
> + /* Clear ASTP 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 &= ~MAC_CONTROL_ASTP;
> +
> + writel(value, ioaddr + MAC_CONTROL);
>
> #ifdef STMMAC_VLAN_TAG_USED
> writel(ETH_P_8021Q, ioaddr + MAC_VLAN1);
> diff --git a/drivers/net/ethernet/stmicro/stmmac/dwmac4_core.c b/drivers/net/ethernet/stmicro/stmmac/dwmac4_core.c
> index f3ed8f7853eb..ed222b20fcf1 100644
> --- a/drivers/net/ethernet/stmicro/stmmac/dwmac4_core.c
> +++ b/drivers/net/ethernet/stmicro/stmmac/dwmac4_core.c
> @@ -17,16 +17,26 @@
> #include <linux/slab.h>
> #include <linux/ethtool.h>
> #include <linux/io.h>
> +#include <net/dsa.h>
> #include "stmmac_pcs.h"
> #include "dwmac4.h"
>
> -static void dwmac4_core_init(struct mac_device_info *hw, int mtu)
> +static void dwmac4_core_init(struct mac_device_info *hw,
> + struct net_device *dev)
> {
> void __iomem *ioaddr = hw->pcsr;
> u32 value = readl(ioaddr + GMAC_CONFIG);
> + int mtu = dev->mtu;
>
> 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 f99f14c35063..7ad841434ec8 100644
> --- a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
> +++ b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
> @@ -2527,7 +2527,7 @@ static int stmmac_hw_setup(struct net_device *dev, bool init_ptp)
> }
>
> /* Initialize the MAC Core */
> - priv->hw->mac->core_init(priv->hw, dev->mtu);
> + priv->hw->mac->core_init(priv->hw, dev);
>
> /* Initialize MTL*/
> if (priv->synopsys_id >= DWMAC_CORE_4_00)
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