amd-xgbe-phy: Check device for current speed mode (KR/KX)

Since device resets can change the current mode it's possible to think
the device is in a different mode than it actually is.  Rather than
trying to determine every place that is needed to set/save the current
mode, be safe and check the devices actual mode when needed rather than
trying to track it.

Signed-off-by: Tom Lendacky <thomas.lendacky@amd.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/drivers/net/phy/amd-xgbe-phy.c b/drivers/net/phy/amd-xgbe-phy.c
index f3230eef41fda7a09442571bb26553ca86b14768..b3cef20637c0b79b8eb7b0344555b56ae9153522 100644 (file)
--- a/drivers/net/phy/amd-xgbe-phy.c
+++ b/drivers/net/phy/amd-xgbe-phy.c
@@ -331,7 +331,6 @@ struct amd_xgbe_phy_priv {
 
        /* Maintain link status for re-starting auto-negotiation */
        unsigned int link;
-       enum amd_xgbe_phy_mode mode;
        unsigned int speed_set;
 
        /* Auto-negotiation state machine support */
@@ -468,8 +467,6 @@ static int amd_xgbe_phy_xgmii_mode(struct phy_device *phydev)
 
        amd_xgbe_phy_serdes_complete_ratechange(phydev);
 
-       priv->mode = AMD_XGBE_MODE_KR;
-
        return 0;
 }
 
@@ -518,8 +515,6 @@ static int amd_xgbe_phy_gmii_2500_mode(struct phy_device *phydev)
 
        amd_xgbe_phy_serdes_complete_ratechange(phydev);
 
-       priv->mode = AMD_XGBE_MODE_KX;
-
        return 0;
 }
 
@@ -568,18 +563,43 @@ static int amd_xgbe_phy_gmii_mode(struct phy_device *phydev)
 
        amd_xgbe_phy_serdes_complete_ratechange(phydev);
 
-       priv->mode = AMD_XGBE_MODE_KX;
+       return 0;
+}
+
+static int amd_xgbe_phy_cur_mode(struct phy_device *phydev,
+                                enum amd_xgbe_phy_mode *mode)
+{
+       int ret;
+
+       ret = phy_read_mmd(phydev, MDIO_MMD_PCS, MDIO_CTRL2);
+       if (ret < 0)
+               return ret;
+
+       if ((ret & MDIO_PCS_CTRL2_TYPE) == MDIO_PCS_CTRL2_10GBR)
+               *mode = AMD_XGBE_MODE_KR;
+       else
+               *mode = AMD_XGBE_MODE_KX;
 
        return 0;
 }
 
+static bool amd_xgbe_phy_in_kr_mode(struct phy_device *phydev)
+{
+       enum amd_xgbe_phy_mode mode;
+
+       if (amd_xgbe_phy_cur_mode(phydev, &mode))
+               return false;
+
+       return (mode == AMD_XGBE_MODE_KR);
+}
+
 static int amd_xgbe_phy_switch_mode(struct phy_device *phydev)
 {
        struct amd_xgbe_phy_priv *priv = phydev->priv;
        int ret;
 
        /* If we are in KR switch to KX, and vice-versa */
-       if (priv->mode == AMD_XGBE_MODE_KR) {
+       if (amd_xgbe_phy_in_kr_mode(phydev)) {
                if (priv->speed_set == AMD_XGBE_PHY_SPEEDSET_1000_10000)
                        ret = amd_xgbe_phy_gmii_mode(phydev);
                else
@@ -591,27 +611,31 @@ static int amd_xgbe_phy_switch_mode(struct phy_device *phydev)
        return ret;
 }
 
-static enum amd_xgbe_phy_an amd_xgbe_an_switch_mode(struct phy_device *phydev)
+static int amd_xgbe_phy_set_mode(struct phy_device *phydev,
+                                enum amd_xgbe_phy_mode mode)
 {
+       enum amd_xgbe_phy_mode cur_mode;
        int ret;
 
-       ret = amd_xgbe_phy_switch_mode(phydev);
-       if (ret < 0)
-               return AMD_XGBE_AN_ERROR;
+       ret = amd_xgbe_phy_cur_mode(phydev, &cur_mode);
+       if (ret)
+               return ret;
 
-       return AMD_XGBE_AN_START;
+       if (mode != cur_mode)
+               ret = amd_xgbe_phy_switch_mode(phydev);
+
+       return ret;
 }
 
 static enum amd_xgbe_phy_an amd_xgbe_an_tx_training(struct phy_device *phydev,
                                                    enum amd_xgbe_phy_rx *state)
 {
-       struct amd_xgbe_phy_priv *priv = phydev->priv;
        int ad_reg, lp_reg, ret;
 
        *state = AMD_XGBE_RX_COMPLETE;
 
-       /* If we're in KX mode then we're done */
-       if (priv->mode == AMD_XGBE_MODE_KX)
+       /* If we're not in KR mode then we're done */
+       if (!amd_xgbe_phy_in_kr_mode(phydev))
                return AMD_XGBE_AN_EVENT;
 
        /* Enable/Disable FEC */
@@ -669,7 +693,6 @@ static enum amd_xgbe_phy_an amd_xgbe_an_tx_xnp(struct phy_device *phydev,
 static enum amd_xgbe_phy_an amd_xgbe_an_rx_bpa(struct phy_device *phydev,
                                               enum amd_xgbe_phy_rx *state)
 {
-       struct amd_xgbe_phy_priv *priv = phydev->priv;
        unsigned int link_support;
        int ret, ad_reg, lp_reg;
 
@@ -679,9 +702,9 @@ static enum amd_xgbe_phy_an amd_xgbe_an_rx_bpa(struct phy_device *phydev,
                return AMD_XGBE_AN_ERROR;
 
        /* Check for a supported mode, otherwise restart in a different one */
-       link_support = (priv->mode == AMD_XGBE_MODE_KR) ? 0x80 : 0x20;
+       link_support = amd_xgbe_phy_in_kr_mode(phydev) ? 0x80 : 0x20;
        if (!(ret & link_support))
-               return amd_xgbe_an_switch_mode(phydev);
+               return AMD_XGBE_AN_INCOMPAT_LINK;
 
        /* Check Extended Next Page support */
        ad_reg = phy_read_mmd(phydev, MDIO_MMD_AN, MDIO_AN_ADVERTISE);
@@ -722,7 +745,7 @@ static enum amd_xgbe_phy_an amd_xgbe_an_start(struct phy_device *phydev)
        int ret;
 
        /* Be sure we aren't looping trying to negotiate */
-       if (priv->mode == AMD_XGBE_MODE_KR) {
+       if (amd_xgbe_phy_in_kr_mode(phydev)) {
                if (priv->kr_state != AMD_XGBE_RX_READY)
                        return AMD_XGBE_AN_NO_LINK;
                priv->kr_state = AMD_XGBE_RX_BPA;
@@ -825,8 +848,8 @@ static enum amd_xgbe_phy_an amd_xgbe_an_page_received(struct phy_device *phydev)
        enum amd_xgbe_phy_rx *state;
        int ret;
 
-       state = (priv->mode == AMD_XGBE_MODE_KR) ? &priv->kr_state
-                                                : &priv->kx_state;
+       state = amd_xgbe_phy_in_kr_mode(phydev) ? &priv->kr_state
+                                               : &priv->kx_state;
 
        switch (*state) {
        case AMD_XGBE_RX_BPA:
@@ -846,7 +869,13 @@ static enum amd_xgbe_phy_an amd_xgbe_an_page_received(struct phy_device *phydev)
 
 static enum amd_xgbe_phy_an amd_xgbe_an_incompat_link(struct phy_device *phydev)
 {
-       return amd_xgbe_an_switch_mode(phydev);
+       int ret;
+
+       ret = amd_xgbe_phy_switch_mode(phydev);
+       if (ret)
+               return AMD_XGBE_AN_ERROR;
+
+       return AMD_XGBE_AN_START;
 }
 
 static void amd_xgbe_an_state_machine(struct work_struct *work)
@@ -1018,7 +1047,6 @@ static int amd_xgbe_phy_config_aneg(struct phy_device *phydev)
 {
        struct amd_xgbe_phy_priv *priv = phydev->priv;
        u32 mmd_mask = phydev->c45_ids.devices_in_package;
-       int ret;
 
        if (phydev->autoneg != AUTONEG_ENABLE)
                return amd_xgbe_phy_setup_forced(phydev);
@@ -1027,11 +1055,6 @@ static int amd_xgbe_phy_config_aneg(struct phy_device *phydev)
        if (!(mmd_mask & MDIO_DEVS_AN))
                return -EINVAL;
 
-       /* Get the current speed mode */
-       ret = phy_read_mmd(phydev, MDIO_MMD_PCS, MDIO_CTRL2);
-       if (ret < 0)
-               return ret;
-
        /* Start/Restart the auto-negotiation state machine */
        mutex_lock(&priv->an_mutex);
        priv->an_result = AMD_XGBE_AN_READY;
@@ -1121,17 +1144,12 @@ static int amd_xgbe_phy_read_status(struct phy_device *phydev)
 {
        struct amd_xgbe_phy_priv *priv = phydev->priv;
        u32 mmd_mask = phydev->c45_ids.devices_in_package;
-       int ret, mode, ad_ret, lp_ret;
+       int ret, ad_ret, lp_ret;
 
        ret = amd_xgbe_phy_update_link(phydev);
        if (ret)
                return ret;
 
-       mode = phy_read_mmd(phydev, MDIO_MMD_PCS, MDIO_CTRL2);
-       if (mode < 0)
-               return mode;
-       mode &= MDIO_PCS_CTRL2_TYPE;
-
        if (phydev->autoneg == AUTONEG_ENABLE) {
                if (!(mmd_mask & MDIO_DEVS_AN))
                        return -EINVAL;
@@ -1163,40 +1181,39 @@ static int amd_xgbe_phy_read_status(struct phy_device *phydev)
                ad_ret &= lp_ret;
                if (ad_ret & 0x80) {
                        phydev->speed = SPEED_10000;
-                       if (mode != MDIO_PCS_CTRL2_10GBR) {
-                               ret = amd_xgbe_phy_xgmii_mode(phydev);
-                               if (ret < 0)
-                                       return ret;
-                       }
+                       ret = amd_xgbe_phy_set_mode(phydev, AMD_XGBE_MODE_KR);
+                       if (ret)
+                               return ret;
                } else {
-                       int (*mode_fcn)(struct phy_device *);
-
-                       if (priv->speed_set ==
-                           AMD_XGBE_PHY_SPEEDSET_1000_10000) {
+                       switch (priv->speed_set) {
+                       case AMD_XGBE_PHY_SPEEDSET_1000_10000:
                                phydev->speed = SPEED_1000;
-                               mode_fcn = amd_xgbe_phy_gmii_mode;
-                       } else {
+                               break;
+
+                       case AMD_XGBE_PHY_SPEEDSET_2500_10000:
                                phydev->speed = SPEED_2500;
-                               mode_fcn = amd_xgbe_phy_gmii_2500_mode;
+                               break;
                        }
 
-                       if (mode == MDIO_PCS_CTRL2_10GBR) {
-                               ret = mode_fcn(phydev);
-                               if (ret < 0)
-                                       return ret;
-                       }
+                       ret = amd_xgbe_phy_set_mode(phydev, AMD_XGBE_MODE_KX);
+                       if (ret)
+                               return ret;
                }
 
                phydev->duplex = DUPLEX_FULL;
        } else {
-               if (mode == MDIO_PCS_CTRL2_10GBR) {
+               if (amd_xgbe_phy_in_kr_mode(phydev)) {
                        phydev->speed = SPEED_10000;
                } else {
-                       if (priv->speed_set ==
-                           AMD_XGBE_PHY_SPEEDSET_1000_10000)
+                       switch (priv->speed_set) {
+                       case AMD_XGBE_PHY_SPEEDSET_1000_10000:
                                phydev->speed = SPEED_1000;
-                       else
+                               break;
+
+                       case AMD_XGBE_PHY_SPEEDSET_2500_10000:
                                phydev->speed = SPEED_2500;
+                               break;
+                       }
                }
                phydev->duplex = DUPLEX_FULL;
                phydev->pause = 0;
@@ -1329,14 +1346,6 @@ static int amd_xgbe_phy_probe(struct phy_device *phydev)
 
        priv->link = 1;
 
-       ret = phy_read_mmd(phydev, MDIO_MMD_PCS, MDIO_CTRL2);
-       if (ret < 0)
-               goto err_sir1;
-       if ((ret & MDIO_PCS_CTRL2_TYPE) == MDIO_PCS_CTRL2_10GBR)
-               priv->mode = AMD_XGBE_MODE_KR;
-       else
-               priv->mode = AMD_XGBE_MODE_KX;
-
        mutex_init(&priv->an_mutex);
        INIT_WORK(&priv->an_work, amd_xgbe_an_state_machine);
        priv->an_workqueue = create_singlethread_workqueue(wq_name);