[TG3]: Fix supporting flowctrl code

This patch does three things.  It modifies tg3_setup_flow_control() to
use the administrator requested flow control settings if
autonegotiation is turned off.  It slightly modifies the
tg3_setup_fiber_mii_phy() function to account for this new use case.
And finally, it does the same for tg3_setup_copper_phy().

The copper modifications are more than a small multi-line change.  The
new code makes an attempt to avoid a link renegotiation if the link is
active at half duplex and the only difference between the current
advertised settings and requested advertised settings is the
flow control advertisements.

Signed-off-by: Matt Carlson <mcarlson@broadcom.com>
Signed-off-by: Michael Chan <mchan@broadcom.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 64 insertions, 43 deletions

diff --git a/drivers/net/tg3.c b/drivers/net/tg3.c
index cdade05bdd07..b2f505d6ea94 100644
--- a/drivers/net/tg3.c
+++ b/drivers/net/tg3.c
@@ -1694,7 +1694,8 @@ static void tg3_setup_flow_control(struct tg3 *tp, u32 local_adv, u32 remote_adv
         u32 old_rx_mode = tp->rx_mode;
         u32 old_tx_mode = tp->tx_mode;
 
-        if (tp->tg3_flags & TG3_FLAG_PAUSE_AUTONEG) {
+        if (tp->link_config.autoneg == AUTONEG_ENABLE &&
+            (tp->tg3_flags & TG3_FLAG_PAUSE_AUTONEG)) {
                 if (tp->tg3_flags2 & TG3_FLG2_ANY_SERDES)
                         new_tg3_flags = tg3_resolve_flowctrl_1000X(local_adv,
                                                                    remote_adv);
@@ -1975,10 +1976,44 @@ static int tg3_copper_is_advertising_all(struct tg3 *tp, u32 mask)
         return 1;
 }
 
+static int tg3_adv_1000T_flowctrl_ok(struct tg3 *tp, u32 *lcladv, u32 *rmtadv)
+{
+        u32 curadv, reqadv;
+
+        if (tg3_readphy(tp, MII_ADVERTISE, lcladv))
+                return 1;
+
+        curadv = *lcladv & (ADVERTISE_PAUSE_CAP | ADVERTISE_PAUSE_ASYM);
+        reqadv = tg3_advert_flowctrl_1000T(tp->link_config.flowctrl);
+
+        if (tp->link_config.active_duplex == DUPLEX_FULL) {
+                if (curadv != reqadv)
+                        return 0;
+
+                if (tp->tg3_flags & TG3_FLAG_PAUSE_AUTONEG)
+                        tg3_readphy(tp, MII_LPA, rmtadv);
+        } else {
+                /* Reprogram the advertisement register, even if it
+                 * does not affect the current link.  If the link
+                 * gets renegotiated in the future, we can save an
+                 * additional renegotiation cycle by advertising
+                 * it correctly in the first place.
+                 */
+                if (curadv != reqadv) {
+                        *lcladv &= ~(ADVERTISE_PAUSE_CAP |
+                                     ADVERTISE_PAUSE_ASYM);
+                        tg3_writephy(tp, MII_ADVERTISE, *lcladv | reqadv);
+                }
+        }
+
+        return 1;
+}
+
 static int tg3_setup_copper_phy(struct tg3 *tp, int force_reset)
 {
         int current_link_up;
         u32 bmsr, dummy;
+        u32 lcl_adv, rmt_adv;
         u16 current_speed;
         u8 current_duplex;
         int i, err;
@@ -2121,54 +2156,35 @@ static int tg3_setup_copper_phy(struct tg3 *tp, int force_reset)
                         udelay(10);
                 }
 
-                if (tp->link_config.autoneg == AUTONEG_ENABLE) {
-                        if (bmcr & BMCR_ANENABLE) {
-                                current_link_up = 1;
+                lcl_adv = 0;
+                rmt_adv = 0;
 
-                                /* Force autoneg restart if we are exiting
-                                 * low power mode.
-                                 */
-                                if (!tg3_copper_is_advertising_all(tp,
-                                                tp->link_config.advertising))
-                                        current_link_up = 0;
-                        } else {
-                                current_link_up = 0;
+                tp->link_config.active_speed = current_speed;
+                tp->link_config.active_duplex = current_duplex;
+
+                if (tp->link_config.autoneg == AUTONEG_ENABLE) {
+                        if ((bmcr & BMCR_ANENABLE) &&
+                            tg3_copper_is_advertising_all(tp,
+                                                tp->link_config.advertising)) {
+                                if (tg3_adv_1000T_flowctrl_ok(tp, &lcl_adv,
+                                                                  &rmt_adv))
+                                        current_link_up = 1;
                         }
                 } else {
                         if (!(bmcr & BMCR_ANENABLE) &&
                             tp->link_config.speed == current_speed &&
-                            tp->link_config.duplex == current_duplex) {
+                            tp->link_config.duplex == current_duplex &&
+                            tp->link_config.flowctrl ==
+                            tp->link_config.active_flowctrl) {
                                 current_link_up = 1;
-                        } else {
-                                current_link_up = 0;
                         }
                 }
 
-                tp->link_config.active_speed = current_speed;
-                tp->link_config.active_duplex = current_duplex;
+                if (current_link_up == 1 &&
+                    tp->link_config.active_duplex == DUPLEX_FULL)
+                        tg3_setup_flow_control(tp, lcl_adv, rmt_adv);
         }
 
-        if (current_link_up == 1 &&
-            (tp->link_config.active_duplex == DUPLEX_FULL) &&
-            (tp->link_config.autoneg == AUTONEG_ENABLE)) {
-                u32 local_adv, remote_adv;
-
-                if (tg3_readphy(tp, MII_ADVERTISE, &local_adv))
-                        local_adv = 0;
-
-                if (tg3_readphy(tp, MII_LPA, &remote_adv))
-                        remote_adv = 0;
-
-                /* If we are not advertising what has been requested,
-                 * bring the link down and reconfigure.
-                 */
-                if (local_adv !=
-                    tg3_advert_flowctrl_1000T(tp->link_config.flowctrl)) {
-                        current_link_up = 0;
-                } else {
-                        tg3_setup_flow_control(tp, local_adv, remote_adv);
-                }
-        }
 relink:
         if (current_link_up == 0 || tp->link_config.phy_is_low_power) {
                 u32 tmp;
@@ -2981,6 +2997,7 @@ static int tg3_setup_fiber_mii_phy(struct tg3 *tp, int force_reset)
         u32 bmsr, bmcr;
         u16 current_speed;
         u8 current_duplex;
+        u32 local_adv, remote_adv;
 
         tp->mac_mode |= MAC_MODE_PORT_MODE_GMII;
         tw32_f(MAC_MODE, tp->mac_mode);
@@ -3014,7 +3031,8 @@ static int tg3_setup_fiber_mii_phy(struct tg3 *tp, int force_reset)
         err |= tg3_readphy(tp, MII_BMCR, &bmcr);
 
         if ((tp->link_config.autoneg == AUTONEG_ENABLE) && !force_reset &&
-            (tp->tg3_flags2 & TG3_FLG2_PARALLEL_DETECT)) {
+            (tp->tg3_flags2 & TG3_FLG2_PARALLEL_DETECT) &&
+             tp->link_config.flowctrl == tp->link_config.active_flowctrl) {
                 /* do nothing, just check for link up at the end */
         } else if (tp->link_config.autoneg == AUTONEG_ENABLE) {
                 u32 adv, new_adv;
@@ -3096,8 +3114,11 @@ static int tg3_setup_fiber_mii_phy(struct tg3 *tp, int force_reset)
                 else
                         current_duplex = DUPLEX_HALF;
 
+                local_adv = 0;
+                remote_adv = 0;
+
                 if (bmcr & BMCR_ANENABLE) {
-                        u32 local_adv, remote_adv, common;
+                        u32 common;
 
                         err |= tg3_readphy(tp, MII_ADVERTISE, &local_adv);
                         err |= tg3_readphy(tp, MII_LPA, &remote_adv);
@@ -3108,15 +3129,15 @@ static int tg3_setup_fiber_mii_phy(struct tg3 *tp, int force_reset)
                                         current_duplex = DUPLEX_FULL;
                                 else
                                         current_duplex = DUPLEX_HALF;
-
-                                tg3_setup_flow_control(tp, local_adv,
-                                                       remote_adv);
                         }
                         else
                                 current_link_up = 0;
                 }
         }
 
+        if (current_link_up == 1 && current_duplex == DUPLEX_FULL)
+                tg3_setup_flow_control(tp, local_adv, remote_adv);
+
         tp->mac_mode &= ~MAC_MODE_HALF_DUPLEX;
         if (tp->link_config.active_duplex == DUPLEX_HALF)
                 tp->mac_mode |= MAC_MODE_HALF_DUPLEX;