net: pcs: xpcs: make the checks related to the PHY interface mode stateless

The operating mode of the driver is currently to populate its
struct mdio_xpcs_args::supported and struct mdio_xpcs_args::an_mode
statically in xpcs_probe(), based on the passed phy_interface_t,
and work with those.

However this is not the operation that phylink expects from a PCS
driver, because the port might be attached to an SFP cage that triggers
changes of the phy_interface_t dynamically as one SFP module is
unpluggged and another is plugged.

To migrate towards that model, the struct mdio_xpcs_args should not
cache anything related to the phy_interface_t, but just look up the
statically defined, const struct xpcs_compat structure corresponding to
the detected PCS OUI/model number.

So we delete the "supported" and "an_mode" members of struct
mdio_xpcs_args, and add the "id" structure there (since the ID is not
expected to change at runtime).

Since xpcs->supported is used deep in the code in _xpcs_config_aneg_c73(),
we need to modify some function headers to pass the xpcs_compat from all
callers. In turn, the xpcs_compat is always supplied externally to the
xpcs module:
- Most of the time by phylink
- In xpcs_probe() it is needed because xpcs_soft_reset() writes to
  MDIO_MMD_PCS or to MDIO_MMD_VEND2 depending on whether an_mode is clause
  37 or clause 73. In order to not introduce functional changes related
  to when the soft reset is issued, we continue to require the initial
  phy_interface_t argument to be passed to xpcs_probe() so we can pass
  this on to xpcs_soft_reset().
- stmmac_open() wants to know whether to call stmmac_init_phy() or not,
  and for that it looks inside xpcs->an_mode, because the clause 73
  (backplane) AN modes supposedly do not have a PHY. Because we moved
  an_mode outside of struct mdio_xpcs_args, this is now no longer
  directly possible, so we introduce a helper function xpcs_get_an_mode()
  which protects the data encapsulation of the xpcs module and requires
  a phy_interface_t to be passed as argument. This function can look up
  the appropriate compat based on the phy_interface_t.

Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
index 13720bf6f6ff90bd3fe97b2eabc59d42a11b12e9..c96a89fa4e3cfd73eb657d7f14d114a36a6d9e67 100644 (file)
--- a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
+++ b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
@@ -3638,6 +3638,7 @@ static int stmmac_request_irq(struct net_device *dev)
 int stmmac_open(struct net_device *dev)
 {
        struct stmmac_priv *priv = netdev_priv(dev);
+       int mode = priv->plat->phy_interface;
        int bfsize = 0;
        u32 chan;
        int ret;
@@ -3650,7 +3651,8 @@ int stmmac_open(struct net_device *dev)
 
        if (priv->hw->pcs != STMMAC_PCS_TBI &&
            priv->hw->pcs != STMMAC_PCS_RTBI &&
-           priv->hw->xpcs_args.an_mode != DW_AN_C73) {
+           (!priv->hw->xpcs ||
+            xpcs_get_an_mode(&priv->hw->xpcs_args, mode) != DW_AN_C73)) {
                ret = stmmac_init_phy(dev);
                if (ret) {
                        netdev_err(priv->dev,

diff --git a/drivers/net/pcs/pcs-xpcs.c b/drivers/net/pcs/pcs-xpcs.c
index 9f2da9e873c48e2c0b2f14b829528ece234dd450..610073cb55d0a23206100a50358ed85a2afd84a2 100644 (file)
--- a/drivers/net/pcs/pcs-xpcs.c
+++ b/drivers/net/pcs/pcs-xpcs.c
@@ -195,6 +195,49 @@ struct xpcs_id {
        const struct xpcs_compat *compat;
 };
 
+static const struct xpcs_compat *xpcs_find_compat(const struct xpcs_id *id,
+                                                 phy_interface_t interface)
+{
+       int i, j;
+
+       for (i = 0; i < DW_XPCS_INTERFACE_MAX; i++) {
+               const struct xpcs_compat *compat = &id->compat[i];
+
+               for (j = 0; j < compat->num_interfaces; j++)
+                       if (compat->interface[j] == interface)
+                               return compat;
+       }
+
+       return NULL;
+}
+
+int xpcs_get_an_mode(struct mdio_xpcs_args *xpcs, phy_interface_t interface)
+{
+       const struct xpcs_compat *compat;
+
+       compat = xpcs_find_compat(xpcs->id, interface);
+       if (!compat)
+               return -ENODEV;
+
+       return compat->an_mode;
+}
+EXPORT_SYMBOL_GPL(xpcs_get_an_mode);
+
+static bool __xpcs_linkmode_supported(const struct xpcs_compat *compat,
+                                     enum ethtool_link_mode_bit_indices linkmode)
+{
+       int i;
+
+       for (i = 0; compat->supported[i] != __ETHTOOL_LINK_MODE_MASK_NBITS; i++)
+               if (compat->supported[i] == linkmode)
+                       return true;
+
+       return false;
+}
+
+#define xpcs_linkmode_supported(compat, mode) \
+       __xpcs_linkmode_supported(compat, ETHTOOL_LINK_MODE_ ## mode ## _BIT)
+
 static int xpcs_read(struct mdio_xpcs_args *xpcs, int dev, u32 reg)
 {
        u32 reg_addr = MII_ADDR_C45 | dev << 16 | reg;
@@ -246,11 +289,12 @@ static int xpcs_poll_reset(struct mdio_xpcs_args *xpcs, int dev)
        return (ret & MDIO_CTRL1_RESET) ? -ETIMEDOUT : 0;
 }
 
-static int xpcs_soft_reset(struct mdio_xpcs_args *xpcs)
+static int xpcs_soft_reset(struct mdio_xpcs_args *xpcs,
+                          const struct xpcs_compat *compat)
 {
        int ret, dev;
 
-       switch (xpcs->an_mode) {
+       switch (compat->an_mode) {
        case DW_AN_C73:
                dev = MDIO_MMD_PCS;
                break;
@@ -419,7 +463,8 @@ static int xpcs_config_usxgmii(struct mdio_xpcs_args *xpcs, int speed)
        return xpcs_write_vpcs(xpcs, MDIO_CTRL1, ret | DW_USXGMII_RST);
 }
 
-static int _xpcs_config_aneg_c73(struct mdio_xpcs_args *xpcs)
+static int _xpcs_config_aneg_c73(struct mdio_xpcs_args *xpcs,
+                                const struct xpcs_compat *compat)
 {
        int ret, adv;
 
@@ -431,7 +476,7 @@ static int _xpcs_config_aneg_c73(struct mdio_xpcs_args *xpcs)
 
        /* SR_AN_ADV3 */
        adv = 0;
-       if (phylink_test(xpcs->supported, 2500baseX_Full))
+       if (xpcs_linkmode_supported(compat, 2500baseX_Full))
                adv |= DW_C73_2500KX;
 
        /* TODO: 5000baseKR */
@@ -442,11 +487,11 @@ static int _xpcs_config_aneg_c73(struct mdio_xpcs_args *xpcs)
 
        /* SR_AN_ADV2 */
        adv = 0;
-       if (phylink_test(xpcs->supported, 1000baseKX_Full))
+       if (xpcs_linkmode_supported(compat, 1000baseKX_Full))
                adv |= DW_C73_1000KX;
-       if (phylink_test(xpcs->supported, 10000baseKX4_Full))
+       if (xpcs_linkmode_supported(compat, 10000baseKX4_Full))
                adv |= DW_C73_10000KX4;
-       if (phylink_test(xpcs->supported, 10000baseKR_Full))
+       if (xpcs_linkmode_supported(compat, 10000baseKR_Full))
                adv |= DW_C73_10000KR;
 
        ret = xpcs_write(xpcs, MDIO_MMD_AN, DW_SR_AN_ADV2, adv);
@@ -455,19 +500,20 @@ static int _xpcs_config_aneg_c73(struct mdio_xpcs_args *xpcs)
 
        /* SR_AN_ADV1 */
        adv = DW_C73_AN_ADV_SF;
-       if (phylink_test(xpcs->supported, Pause))
+       if (xpcs_linkmode_supported(compat, Pause))
                adv |= DW_C73_PAUSE;
-       if (phylink_test(xpcs->supported, Asym_Pause))
+       if (xpcs_linkmode_supported(compat, Asym_Pause))
                adv |= DW_C73_ASYM_PAUSE;
 
        return xpcs_write(xpcs, MDIO_MMD_AN, DW_SR_AN_ADV1, adv);
 }
 
-static int xpcs_config_aneg_c73(struct mdio_xpcs_args *xpcs)
+static int xpcs_config_aneg_c73(struct mdio_xpcs_args *xpcs,
+                               const struct xpcs_compat *compat)
 {
        int ret;
 
-       ret = _xpcs_config_aneg_c73(xpcs);
+       ret = _xpcs_config_aneg_c73(xpcs, compat);
        if (ret < 0)
                return ret;
 
@@ -481,7 +527,8 @@ static int xpcs_config_aneg_c73(struct mdio_xpcs_args *xpcs)
 }
 
 static int xpcs_aneg_done_c73(struct mdio_xpcs_args *xpcs,
-                             struct phylink_link_state *state)
+                             struct phylink_link_state *state,
+                             const struct xpcs_compat *compat)
 {
        int ret;
 
@@ -496,7 +543,7 @@ static int xpcs_aneg_done_c73(struct mdio_xpcs_args *xpcs,
 
                /* Check if Aneg outcome is valid */
                if (!(ret & DW_C73_AN_ADV_SF)) {
-                       xpcs_config_aneg_c73(xpcs);
+                       xpcs_config_aneg_c73(xpcs, compat);
                        return 0;
                }
 
@@ -642,8 +689,31 @@ static int xpcs_validate(struct mdio_xpcs_args *xpcs,
                         unsigned long *supported,
                         struct phylink_link_state *state)
 {
-       linkmode_and(supported, supported, xpcs->supported);
-       linkmode_and(state->advertising, state->advertising, xpcs->supported);
+       __ETHTOOL_DECLARE_LINK_MODE_MASK(xpcs_supported);
+       const struct xpcs_compat *compat;
+       int i;
+
+       /* phylink expects us to report all supported modes with
+        * PHY_INTERFACE_MODE_NA, just don't limit the supported and
+        * advertising masks and exit.
+        */
+       if (state->interface == PHY_INTERFACE_MODE_NA)
+               return 0;
+
+       bitmap_zero(xpcs_supported, __ETHTOOL_LINK_MODE_MASK_NBITS);
+
+       compat = xpcs_find_compat(xpcs->id, state->interface);
+
+       /* Populate the supported link modes for this
+        * PHY interface type
+        */
+       if (compat)
+               for (i = 0; compat->supported[i] != __ETHTOOL_LINK_MODE_MASK_NBITS; i++)
+                       set_bit(compat->supported[i], xpcs_supported);
+
+       linkmode_and(supported, supported, xpcs_supported);
+       linkmode_and(state->advertising, state->advertising, xpcs_supported);
+
        return 0;
 }
 
@@ -724,12 +794,17 @@ static int xpcs_config_aneg_c37_sgmii(struct mdio_xpcs_args *xpcs)
 static int xpcs_config(struct mdio_xpcs_args *xpcs,
                       const struct phylink_link_state *state)
 {
+       const struct xpcs_compat *compat;
        int ret;
 
-       switch (xpcs->an_mode) {
+       compat = xpcs_find_compat(xpcs->id, state->interface);
+       if (!compat)
+               return -ENODEV;
+
+       switch (compat->an_mode) {
        case DW_AN_C73:
                if (state->an_enabled) {
-                       ret = xpcs_config_aneg_c73(xpcs);
+                       ret = xpcs_config_aneg_c73(xpcs, compat);
                        if (ret)
                                return ret;
                }
@@ -747,7 +822,8 @@ static int xpcs_config(struct mdio_xpcs_args *xpcs,
 }
 
 static int xpcs_get_state_c73(struct mdio_xpcs_args *xpcs,
-                             struct phylink_link_state *state)
+                             struct phylink_link_state *state,
+                             const struct xpcs_compat *compat)
 {
        int ret;
 
@@ -757,7 +833,7 @@ static int xpcs_get_state_c73(struct mdio_xpcs_args *xpcs,
        /* ... and then we check the faults. */
        ret = xpcs_read_fault_c73(xpcs, state);
        if (ret) {
-               ret = xpcs_soft_reset(xpcs);
+               ret = xpcs_soft_reset(xpcs, compat);
                if (ret)
                        return ret;
 
@@ -766,7 +842,7 @@ static int xpcs_get_state_c73(struct mdio_xpcs_args *xpcs,
                return xpcs_config(xpcs, state);
        }
 
-       if (state->an_enabled && xpcs_aneg_done_c73(xpcs, state)) {
+       if (state->an_enabled && xpcs_aneg_done_c73(xpcs, state, compat)) {
                state->an_complete = true;
                xpcs_read_lpa_c73(xpcs, state);
                xpcs_resolve_lpa_c73(xpcs, state);
@@ -823,11 +899,16 @@ static int xpcs_get_state_c37_sgmii(struct mdio_xpcs_args *xpcs,
 static int xpcs_get_state(struct mdio_xpcs_args *xpcs,
                          struct phylink_link_state *state)
 {
+       const struct xpcs_compat *compat;
        int ret;
 
-       switch (xpcs->an_mode) {
+       compat = xpcs_find_compat(xpcs->id, state->interface);
+       if (!compat)
+               return -ENODEV;
+
+       switch (compat->an_mode) {
        case DW_AN_C73:
-               ret = xpcs_get_state_c73(xpcs, state);
+               ret = xpcs_get_state_c73(xpcs, state, compat);
                if (ret)
                        return ret;
                break;
@@ -890,40 +971,6 @@ static u32 xpcs_get_id(struct mdio_xpcs_args *xpcs)
        return 0xffffffff;
 }
 
-static bool xpcs_check_features(struct mdio_xpcs_args *xpcs,
-                               const struct xpcs_id *match,
-                               phy_interface_t interface)
-{
-       int i, j;
-
-       for (i = 0; i < DW_XPCS_INTERFACE_MAX; i++) {
-               const struct xpcs_compat *compat = &match->compat[i];
-               bool supports_interface = false;
-
-               for (j = 0; j < compat->num_interfaces; j++) {
-                       if (compat->interface[j] == interface) {
-                               supports_interface = true;
-                               break;
-                       }
-               }
-
-               if (!supports_interface)
-                       continue;
-
-               /* Populate the supported link modes for this
-                * PHY interface type
-                */
-               for (j = 0; compat->supported[j] != __ETHTOOL_LINK_MODE_MASK_NBITS; j++)
-                       set_bit(compat->supported[j], xpcs->supported);
-
-               xpcs->an_mode = compat->an_mode;
-
-               return true;
-       }
-
-       return false;
-}
-
 static const struct xpcs_compat synopsys_xpcs_compat[DW_XPCS_INTERFACE_MAX] = {
        [DW_XPCS_USXGMII] = {
                .supported = xpcs_usxgmii_features,
@@ -961,19 +1008,23 @@ static const struct xpcs_id xpcs_id_list[] = {
 
 static int xpcs_probe(struct mdio_xpcs_args *xpcs, phy_interface_t interface)
 {
-       const struct xpcs_id *match = NULL;
        u32 xpcs_id = xpcs_get_id(xpcs);
        int i;
 
        for (i = 0; i < ARRAY_SIZE(xpcs_id_list); i++) {
                const struct xpcs_id *entry = &xpcs_id_list[i];
+               const struct xpcs_compat *compat;
 
-               if ((xpcs_id & entry->mask) == entry->id) {
-                       match = entry;
+               if ((xpcs_id & entry->mask) != entry->id)
+                       continue;
 
-                       if (xpcs_check_features(xpcs, match, interface))
-                               return xpcs_soft_reset(xpcs);
-               }
+               xpcs->id = entry;
+
+               compat = xpcs_find_compat(entry, interface);
+               if (!compat)
+                       return -ENODEV;
+
+               return xpcs_soft_reset(xpcs, compat);
        }
 
        return -ENODEV;

diff --git a/include/linux/pcs/pcs-xpcs.h b/include/linux/pcs/pcs-xpcs.h
index c4d0a2c469c7a31a4319a7b3c9cecd337f2691cc..c2ec440d2c5d25d71affe24a437f9b12936490f1 100644 (file)
--- a/include/linux/pcs/pcs-xpcs.h
+++ b/include/linux/pcs/pcs-xpcs.h
@@ -14,11 +14,12 @@
 #define DW_AN_C73                      1
 #define DW_AN_C37_SGMII                        2
 
+struct xpcs_id;
+
 struct mdio_xpcs_args {
-       __ETHTOOL_DECLARE_LINK_MODE_MASK(supported);
        struct mii_bus *bus;
+       const struct xpcs_id *id;
        int addr;
-       int an_mode;
 };
 
 struct mdio_xpcs_ops {
@@ -36,6 +37,7 @@ struct mdio_xpcs_ops {
                          int enable);
 };
 
+int xpcs_get_an_mode(struct mdio_xpcs_args *xpcs, phy_interface_t interface);
 struct mdio_xpcs_ops *mdio_xpcs_get_ops(void);
 
 #endif /* __LINUX_PCS_XPCS_H */