ARM: mxs: store mac address read from OTP in device tree

The non-DT boot reads the mac from OTP and pass it to fec driver via
platform data.  The patch provides an equivalent support for device
tree boot, with reading mac from OTP and store it in device tree,
and fec driver can get the mac from device tree at its probe time.
Signed-off-by: NShawn Guo <shawn.guo@linaro.org>

arch/arm/mach-mxs/mach-mxs.c

@@ -71,6 +71,68 @@ static struct sys_timer imx28_timer = {
 	.init = imx28_timer_init,
 };
 
+enum mac_oui {
+	OUI_FSL,
+	OUI_DENX,
+};
+
+static void __init update_fec_mac_prop(enum mac_oui oui)
+{
+	struct device_node *np, *from = NULL;
+	struct property *oldmac, *newmac;
+	const u32 *ocotp = mxs_get_ocotp();
+	u8 *macaddr;
+	u32 val;
+	int i;
+
+	for (i = 0; i < 2; i++) {
+		np = of_find_compatible_node(from, NULL, "fsl,imx28-fec");
+		if (!np)
+			return;
+		from = np;
+
+		newmac = kzalloc(sizeof(*newmac) + 6, GFP_KERNEL);
+		if (!newmac)
+			return;
+		newmac->value = newmac + 1;
+		newmac->length = 6;
+
+		newmac->name = kstrdup("local-mac-address", GFP_KERNEL);
+		if (!newmac->name) {
+			kfree(newmac);
+			return;
+		}
+
+		/*
+		 * OCOTP only stores the last 4 octets for each mac address,
+		 * so hard-code OUI here.
+		 */
+		macaddr = newmac->value;
+		switch (oui) {
+		case OUI_FSL:
+			macaddr[0] = 0x00;
+			macaddr[1] = 0x04;
+			macaddr[2] = 0x9f;
+			break;
+		case OUI_DENX:
+			macaddr[0] = 0xc0;
+			macaddr[1] = 0xe5;
+			macaddr[2] = 0x4e;
+			break;
+		}
+		val = ocotp[i];
+		macaddr[3] = (val >> 16) & 0xff;
+		macaddr[4] = (val >> 8) & 0xff;
+		macaddr[5] = (val >> 0) & 0xff;
+
+		oldmac = of_find_property(np, newmac->name, NULL);
+		if (oldmac)
+			prom_update_property(np, newmac, oldmac);
+		else
+			prom_add_property(np, newmac);
+	}
+}
+
 static void __init imx28_evk_init(void)
 {
 	struct clk *clk;
@@ -79,6 +141,8 @@ static void __init imx28_evk_init(void)
 	clk = clk_get_sys("enet_out", NULL);
 	if (!IS_ERR(clk))
 		clk_prepare_enable(clk);
+
+	update_fec_mac_prop(OUI_FSL);
 }
 
 static void __init mxs_machine_init(void)