net: netcp: Fixes SGMII reset on network interface shutdown

This patch asserts SGMII RTRESET, i.e. resetting the SGMII Tx/Rx
logic,  during network interface shutdown to avoid having the
hardware wedge when shutting down with high incoming traffic rates.
This is cleared (brought out of RTRESET) when the interface is
brought back up.

Signed-off-by: WingMan Kwok <w-kwok2@ti.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/drivers/net/ethernet/ti/netcp.h b/drivers/net/ethernet/ti/netcp.h
index bbacf5cccec2fcbc3831e8f61b559d51a5211816..a8a730641bbb14e723f841b2b3c13454b53a5491 100644 (file)
--- a/drivers/net/ethernet/ti/netcp.h
+++ b/drivers/net/ethernet/ti/netcp.h
@@ -223,6 +223,7 @@ void *netcp_device_find_module(struct netcp_device *netcp_device,
 
 /* SGMII functions */
 int netcp_sgmii_reset(void __iomem *sgmii_ofs, int port);
+bool netcp_sgmii_rtreset(void __iomem *sgmii_ofs, int port, bool set);
 int netcp_sgmii_get_port_link(void __iomem *sgmii_ofs, int port);
 int netcp_sgmii_config(void __iomem *sgmii_ofs, int port, u32 interface);
 

diff --git a/drivers/net/ethernet/ti/netcp_ethss.c b/drivers/net/ethernet/ti/netcp_ethss.c
index 9b7e0a34c98b10aca5eed610c47f33b2eedbbd00..a21881219865952d907f36df1f4013d1953d9539 100644 (file)
--- a/drivers/net/ethernet/ti/netcp_ethss.c
+++ b/drivers/net/ethernet/ti/netcp_ethss.c
@@ -1901,11 +1901,28 @@ static void gbe_port_config(struct gbe_priv *gbe_dev, struct gbe_slave *slave,
        writel(slave->mac_control, GBE_REG_ADDR(slave, emac_regs, mac_control));
 }
 
+static void gbe_sgmii_rtreset(struct gbe_priv *priv,
+                             struct gbe_slave *slave, bool set)
+{
+       void __iomem *sgmii_port_regs;
+
+       if (SLAVE_LINK_IS_XGMII(slave))
+               return;
+
+       if ((priv->ss_version == GBE_SS_VERSION_14) && (slave->slave_num >= 2))
+               sgmii_port_regs = priv->sgmii_port34_regs;
+       else
+               sgmii_port_regs = priv->sgmii_port_regs;
+
+       netcp_sgmii_rtreset(sgmii_port_regs, slave->slave_num, set);
+}
+
 static void gbe_slave_stop(struct gbe_intf *intf)
 {
        struct gbe_priv *gbe_dev = intf->gbe_dev;
        struct gbe_slave *slave = intf->slave;
 
+       gbe_sgmii_rtreset(gbe_dev, slave, true);
        gbe_port_reset(slave);
        /* Disable forwarding */
        cpsw_ale_control_set(gbe_dev->ale, slave->port_num,
@@ -1947,6 +1964,7 @@ static int gbe_slave_open(struct gbe_intf *gbe_intf)
 
        gbe_sgmii_config(priv, slave);
        gbe_port_reset(slave);
+       gbe_sgmii_rtreset(priv, slave, false);
        gbe_port_config(priv, slave, priv->rx_packet_max);
        gbe_set_slave_mac(slave, gbe_intf);
        /* enable forwarding */

diff --git a/drivers/net/ethernet/ti/netcp_sgmii.c b/drivers/net/ethernet/ti/netcp_sgmii.c
index dbeb14266e2fb106c8a16b7d32b73fbc28095ec7..5d8419f658d04397a7be30c2a1b9a249f492e6e8 100644 (file)
--- a/drivers/net/ethernet/ti/netcp_sgmii.c
+++ b/drivers/net/ethernet/ti/netcp_sgmii.c
@@ -18,6 +18,9 @@
 
 #include "netcp.h"
 
+#define SGMII_SRESET_RESET             BIT(0)
+#define SGMII_SRESET_RTRESET           BIT(1)
+
 #define SGMII_REG_STATUS_LOCK          BIT(4)
 #define        SGMII_REG_STATUS_LINK           BIT(0)
 #define SGMII_REG_STATUS_AUTONEG       BIT(2)
@@ -51,12 +54,35 @@ static void sgmii_write_reg_bit(void __iomem *base, int reg, u32 val)
 int netcp_sgmii_reset(void __iomem *sgmii_ofs, int port)
 {
        /* Soft reset */
-       sgmii_write_reg_bit(sgmii_ofs, SGMII_SRESET_REG(port), 0x1);
-       while (sgmii_read_reg(sgmii_ofs, SGMII_SRESET_REG(port)) != 0x0)
+       sgmii_write_reg_bit(sgmii_ofs, SGMII_SRESET_REG(port),
+                           SGMII_SRESET_RESET);
+
+       while ((sgmii_read_reg(sgmii_ofs, SGMII_SRESET_REG(port)) &
+               SGMII_SRESET_RESET) != 0x0)
                ;
+
        return 0;
 }
 
+/* port is 0 based */
+bool netcp_sgmii_rtreset(void __iomem *sgmii_ofs, int port, bool set)
+{
+       u32 reg;
+       bool oldval;
+
+       /* Initiate a soft reset */
+       reg = sgmii_read_reg(sgmii_ofs, SGMII_SRESET_REG(port));
+       oldval = (reg & SGMII_SRESET_RTRESET) != 0x0;
+       if (set)
+               reg |= SGMII_SRESET_RTRESET;
+       else
+               reg &= ~SGMII_SRESET_RTRESET;
+       sgmii_write_reg(sgmii_ofs, SGMII_SRESET_REG(port), reg);
+       wmb();
+
+       return oldval;
+}
+
 int netcp_sgmii_get_port_link(void __iomem *sgmii_ofs, int port)
 {
        u32 status = 0, link = 0;