ARM: i.MX6: add ethernet phy fixup for AR8031

The AR8031 is used on the i.MX6 based sabreSD, sabreauto and wandboard.
All need the same fixup, so add it for all i.MX6.

Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
Signed-off-by: Shawn Guo <shawn.guo@linaro.org>
diff --git a/arch/arm/mach-imx/mach-imx6q.c b/arch/arm/mach-imx/mach-imx6q.c
index 7f23846..57f350c 100644
--- a/arch/arm/mach-imx/mach-imx6q.c
+++ b/arch/arm/mach-imx/mach-imx6q.c
@@ -115,6 +115,29 @@
 	return 0;
 }
 
+static int ar8031_phy_fixup(struct phy_device *dev)
+{
+	u16 val;
+
+	/* To enable AR8031 output a 125MHz clk from CLK_25M */
+	phy_write(dev, 0xd, 0x7);
+	phy_write(dev, 0xe, 0x8016);
+	phy_write(dev, 0xd, 0x4007);
+
+	val = phy_read(dev, 0xe);
+	val &= 0xffe3;
+	val |= 0x18;
+	phy_write(dev, 0xe, val);
+
+	/* introduce tx clock delay */
+	phy_write(dev, 0x1d, 0x5);
+	val = phy_read(dev, 0x1e);
+	val |= 0x0100;
+	phy_write(dev, 0x1e, val);
+
+	return 0;
+}
+
 static void __init imx6q_sabrelite_cko1_setup(void)
 {
 	struct clk *cko1_sel, *ahb, *cko1;
@@ -139,11 +162,15 @@
 		clk_put(cko1);
 }
 
+#define PHY_ID_AR8031	0x004dd074
+
 static void __init imx6q_enet_phy_init(void)
 {
 	if (IS_BUILTIN(CONFIG_PHYLIB)) {
 		phy_register_fixup_for_uid(PHY_ID_KSZ9021, MICREL_PHY_ID_MASK,
 				ksz9021rn_phy_fixup);
+		phy_register_fixup_for_uid(PHY_ID_AR8031, 0xffffffff,
+				ar8031_phy_fixup);
 	}
 }