tg3 / broadcom: Optionally disable TXC if no link

This patch adds code to disable the TXC and RXC reference clocks if link
is not available.

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

drivers/net/phy/broadcom.c

@@ -108,6 +108,7 @@
 #define BCM54XX_SHD_SCR3		0x05
 #define  BCM54XX_SHD_SCR3_DEF_CLK125	0x0001
 #define  BCM54XX_SHD_SCR3_DLLAPD_DIS	0x0002
+#define  BCM54XX_SHD_SCR3_TRDDAPD	0x0004
 
 /* 01010: Auto Power-Down */
 #define BCM54XX_SHD_APD			0x0a
@@ -362,6 +363,9 @@ static void bcm54xx_adjust_rxrefclk(struct phy_device *phydev)
 	else
 		val |= BCM54XX_SHD_SCR3_DLLAPD_DIS;
 
+	if (phydev->dev_flags & PHY_BRCM_DIS_TXCRXC_NOENRGY)
+		val |= BCM54XX_SHD_SCR3_TRDDAPD;
+
 	if (orig != val)
 		bcm54xx_shadow_write(phydev, BCM54XX_SHD_SCR3, val);
 
@@ -409,6 +413,7 @@ static int bcm54xx_config_init(struct phy_device *phydev)
 		bcm54xx_shadow_write(phydev, BCM54XX_SHD_RGMII_MODE, 0);
 
 	if ((phydev->dev_flags & PHY_BRCM_RX_REFCLK_UNUSED) ||
+	    (phydev->dev_flags & PHY_BRCM_DIS_TXCRXC_NOENRGY) ||
 	    (phydev->dev_flags & PHY_BRCM_AUTO_PWRDWN_ENABLE))
 		bcm54xx_adjust_rxrefclk(phydev);
 

drivers/net/tg3.c

@@ -1103,6 +1103,7 @@ static int tg3_mdio_init(struct tg3 *tp)
 	case TG3_PHY_ID_BCM50610M:
 		phydev->dev_flags |= PHY_BRCM_CLEAR_RGMII_MODE |
 				     PHY_BRCM_RX_REFCLK_UNUSED |
+				     PHY_BRCM_DIS_TXCRXC_NOENRGY |
 				     PHY_BRCM_AUTO_PWRDWN_ENABLE;
 		if (tp->tg3_flags3 & TG3_FLG3_RGMII_STD_IBND_DISABLE)
 			phydev->dev_flags |= PHY_BRCM_STD_IBND_DISABLE;

include/linux/brcmphy.h

@@ -9,4 +9,5 @@
 #define PHY_BRCM_EXT_IBND_RX_ENABLE	0x00001000
 #define PHY_BRCM_EXT_IBND_TX_ENABLE	0x00002000
 #define PHY_BRCM_CLEAR_RGMII_MODE	0x00004000
+#define PHY_BRCM_DIS_TXCRXC_NOENRGY	0x00008000
 #define PHY_BCM_FLAGS_VALID		0x80000000