ARM: dts: omap: Add common file for SMSC9221

Some devices (SMSC9217, SMSC9218 and SMSC9221 at least) have better
timings, allowing a higher transfer speed. Create a common file
with these timings.

Performance results with iperf:

- omap-gpmc-smsc911x.dtsi => 54.9 Mbps
- omap-gpmc-smsc9221.dtsi => 92.7 Mbps

Signed-off-by: Florian Vaussard <[e-mail]>
Signed-off-by: Tony Lindgren <[e-mail]>

arch/arm/boot/dts/omap-gpmc-smsc9221.dtsi

···
+/*
+ * Common file for GPMC connected smsc9221 on omaps
+ *
+ * Compared to smsc911x, smsc9221 (and others like smsc9217
+ * or smsc 9218) has faster timings, leading to higher
+ * bandwidth.
+ *
+ * Note that the board specifc DTS file needs to specify
+ * ranges, pinctrl, reg, interrupt parent and interrupts.
+ */
+
+/ {
+	vddvario: regulator-vddvario {
+		  compatible = "regulator-fixed";
+		  regulator-name = "vddvario";
+		  regulator-always-on;
+	};
+
+	vdd33a: regulator-vdd33a {
+		compatible = "regulator-fixed";
+		regulator-name = "vdd33a";
+		regulator-always-on;
+	};
+};
+
+&gpmc {
+	ethernet@gpmc {
+		compatible = "smsc,lan9221","smsc,lan9115";
+		bank-width = <2>;
+
+		gpmc,mux-add-data;
+		gpmc,cs-on-ns = <0>;
+		gpmc,cs-rd-off-ns = <42>;
+		gpmc,cs-wr-off-ns = <36>;
+		gpmc,adv-on-ns = <6>;
+		gpmc,adv-rd-off-ns = <12>;
+		gpmc,adv-wr-off-ns = <12>;
+		gpmc,oe-on-ns = <0>;
+		gpmc,oe-off-ns = <42>;
+		gpmc,we-on-ns = <0>;
+		gpmc,we-off-ns = <36>;
+		gpmc,rd-cycle-ns = <60>;
+		gpmc,wr-cycle-ns = <54>;
+		gpmc,access-ns = <36>;
+		gpmc,page-burst-access-ns = <0>;
+		gpmc,bus-turnaround-ns = <0>;
+		gpmc,cycle2cycle-delay-ns = <0>;
+		gpmc,wr-data-mux-bus-ns = <18>;
+		gpmc,wr-access-ns = <42>;
+		gpmc,cycle2cycle-samecsen;
+		gpmc,cycle2cycle-diffcsen;
+
+		vddvario-supply = <&vddvario>;
+		vdd33a-supply = <&vdd33a>;
+		reg-io-width = <4>;
+		smsc,save-mac-address;
+	};
+};