1 files changed, 16 insertions, 0 deletions

diff --git a/drivers/net/tg3.c b/drivers/net/tg3.c
index bb3b73435170..ecd64a224e95 100644
--- a/drivers/net/tg3.c
+++ b/drivers/net/tg3.c
@@ -3154,6 +3154,22 @@ static int tg3_setup_phy(struct tg3 *tp, int force_reset)
                 err = tg3_setup_copper_phy(tp, force_reset);
         }
 
+        if (tp->pci_chip_rev_id == CHIPREV_ID_5784_A0) {
+                u32 val, scale;
+
+                val = tr32(TG3_CPMU_CLCK_STAT) & CPMU_CLCK_STAT_MAC_CLCK_MASK;
+                if (val == CPMU_CLCK_STAT_MAC_CLCK_62_5)
+                        scale = 65;
+                else if (val == CPMU_CLCK_STAT_MAC_CLCK_6_25)
+                        scale = 6;
+                else
+                        scale = 12;
+
+                val = tr32(GRC_MISC_CFG) & ~GRC_MISC_CFG_PRESCALAR_MASK;
+                val |= (scale << GRC_MISC_CFG_PRESCALAR_SHIFT);
+                tw32(GRC_MISC_CFG, val);
+        }
+
         if (tp->link_config.active_speed == SPEED_1000 &&
             tp->link_config.active_duplex == DUPLEX_HALF)
                 tw32(MAC_TX_LENGTHS,