N900 device tree conversion: how to do first step

[Aaro Koskinen]

Hi,

On Sun, Jun 09, 2013 at 03:59:44AM +0200, Pavel Machek wrote:
> I'd like to convert Nokia N900 to device tree.
> 
> Unfortunately, serial port is not easily available (very special cable
> would be needed, does someone know where to get one?) and I don't have
> BDI (and very special cable would be needed, too).
> 
> So I tried doing very small first step, hoping that I get booting
> system... obviously I did not.

The following works for me, it's enough to boot and get the USB networking
working. After that I can connect to the device with ssh. I don't use
serial either, I just have initramfs with busybox+dropbear with hardcoded
interface setup.

---8<---

/dts-v1/;

/include/ "omap34xx.dtsi"

/ {
	model = "Nokia N900";
	compatible = "nokia,omap3-n900", "ti,omap3";

	cpus {
		cpu at 0 {
			cpu0-supply = <&vcc>;
		};
	};

	memory {
		device_type = "memory";
		reg = <0x80000000 0x10000000>; /* 256 MB */
	};

};

&i2c1 {
	clock-frequency = <2200000>;

	twl: twl at 48 {
		reg = <0x48>;
		interrupts = <7>; /* SYS_NIRQ cascaded to intc */
		interrupt-parent = <&intc>;
	};
};

/include/ "twl4030.dtsi"

&twl_gpio {
	ti,pullups	= <0x0>;
	ti,pulldowns	= <0x03ff3f>; /* BIT(0..5) | BIT(8..17) */
};

&i2c2 {
	clock-frequency = <400000>;
};

&i2c3 {
	clock-frequency = <100000>;
};

&mmc1 {
	status = "disabled";
};

&mmc2 {
	status = "disabled";
};

&mmc3 {
	status = "disabled";
};

&usb_otg_hs {
	interface-type = <0>;
	usb-phy = <&usb2_phy>;
	mode = <2>;
	power = <50>;
};