Fetch and build flinklinux:

$ cd $WD
$ git clone https://github.com/flink-project/flinklinux.git -o upstream
$ cd flinklinux
$ make 

The device tree file is compiled with the kernel. The output file is: arch/arm/boot/dts/imx6dl-colibri-efs.dtb This file has to be passed to the kernel during boot. The source of this file was based on the device tree file of the eval board. The weim node was changed to reflect the hardware of the footplate. Instead of two SRAM modules an FPGA is connected to the EIM bus.

The relevant part is listed here:

&weim {
	status = "okay";
	/* weim memory map: 32MB on CS0, 32MB on CS1, 32MB on CS2 */
	ranges = <0 0 0x08000000 0x02000000
	          1 0 0x0a000000 0x02000000
	          2 0 0x0c000000 0x02000000>;
	/* FPGA on CS0 */
	fpga@0,0 {
		compatible = "ntb,flink_eim_driver";
		reg = <0 0 0x00080000>;
		#address-cells = <1>;
		#size-cells = <1>;
		bank-width = <2>;
		fsl,weim-cs-timing = <0x07710081 0x00000100 0x04000000
				0x00000000 0x04000040 0x00000000>;
	};
};

The ranges property determines the memory areas for 3 chip selects. The size of each region is 32 MB. CS0 starts at 0x08000000 and is used for the FPGA. Only 512 KB are used for the FPGA because the address width is 16 bit. The kernel module maps the amount of memory which is in the reg property of the fpga node.

The property fsl,weim-cs-timing sets 6 configuration registers of the EIM bus (EIM_CS0GCR1, EIM_CS0GCR2, EIM_CS0RCR1, EIM_CS0RCR2, EIM_CS0WCR1 and EIM_CS0WCR2).

The compatible string determines which driver is loaded, in our case it's the flink_eim.ko kernel module (ntb,flink_eim_driver).

This is the complete file:

/*
 * Copyright 2014 Toradex AG
 * Copyright 2012 Freescale Semiconductor, Inc.
 * Copyright 2011 Linaro Ltd.
 *
 * The code contained herein is licensed under the GNU General Public
 * License. You may obtain a copy of the GNU General Public License
 * Version 2 or later at the following locations:
 *
 * http://www.opensource.org/licenses/gpl-license.html
 * http://www.gnu.org/copyleft/gpl.html
 */

/dts-v1/;

#include <dt-bindings/interrupt-controller/irq.h>
#include "imx6dl.dtsi"
#include "imx6qdl-colibri.dtsi"

/ {
	model = "Toradex Colibri iMX6DL/S on EFS mainboard";
	compatible = "toradex,colibri_imx6dl-eval", "toradex,colibri_imx6dl", "fsl,imx6dl";

	aliases {
		rtc0 = &rtc_i2c;
		rtc1 = "/soc/aips-bus@02000000/snvs@020cc000/snvs-rtc-lp@34";
	};

	aliases {
		/* the following, together with kernel patches, forces a fixed assignment
		   between device id and usdhc controller */
		/* i.e. the eMMC on usdhc3 will be /dev/mmcblk0 */
		mmc0 = &usdhc3; /* eMMC */
		mmc1 = &usdhc1; /* MMC 4bit slot */
	};

	gpio-keys {
		compatible = "gpio-keys";
		pinctrl-names = "default";
		pinctrl-0 = <&pinctrl_gpio_keys>;

		wakeup {
			label = "Wakeup";
			gpios = <&gpio2 22 GPIO_ACTIVE_HIGH>;
			linux,code = <KEY_WAKEUP>;
			debounce-interval = <10>;
			gpio-key,wakeup;
		};
	};

	pwmleds {
		compatible = "pwm-leds";
		ledpwm2 {
			label = "PWM<B>";
			pwms = <&pwm1 0 50000>;
			max-brightness = <255>;
		};

		ledpwm3 {
			label = "PWM<C>";
			pwms = <&pwm4 0 50000>;
			max-brightness = <255>;
		};

		ledpwm4 {
			label = "PWM<D>";
			pwms = <&pwm2 0 50000>;
			max-brightness = <255>;
		};
	};

	regulators {
		reg_usb_host_vbus: usb_host_vbus {
			status = "okay";
		};
	};
};

&backlight {
#if 0
	/* PWM polarity: 1 is brightest */
	brightness-levels = <0 4 8 16 32 64 128 255>;
	default-brightness-level = <6>;
#else
	/* PWM plarity: 0 is brightest */
	brightness-levels = <0 74 128 164 192 210 255>;
	default-brightness-level = <1>;
#endif
	status = "okay";
};

/* Colibri SPI */
&ecspi4 {
	status = "okay";

	spidev0: spidev@1 {
		compatible = "spidev";
		reg = <0>;
		spi-max-frequency = <50000000>;
	};
};

&hdmi_audio {
	status = "okay";
};

&hdmi_core {
	status = "okay";
};

&hdmi_video {
	status = "okay";
};

/*
 * I2C: I2C3_SDA/SCL on SODIMM pin 194/196 (e.g. RTC on carrier
 * board)
 */
&i2c3 {
	status = "okay";
#if 0 /* not standard pinout, disable PWM<B>, PWM<C>
	pcap@10 {
		/* TouchRevolution Fusion 7 and 10 multi-touch controller */
		compatible = "touchrevolution,fusion-f0710a";
		reg = <0x10>;
		gpios = <&gpio1  9 0 /* SODIMM-28, Pen down interrupt */
			 &gpio2 10 0 /* SODIMM-30, Reset */
			>;
	};
#endif
	/* M41T0M6 real time clock on carrier board */
	rtc_i2c: rtc@68 {
		compatible = "st,m41t00";
		reg = <0x68>;
	};
};

/*
 * DDC_I2C: I2C2_SDA/SCL on MXM3 pin 205/207
 */
&i2cddc {
	status = "okay";

	hdmi: edid@50 {
		compatible = "fsl,imx6-hdmi-i2c";
		reg = <0x50>;
	};
};

&iomuxc {
	/*
	 * Mux all pins which are unused to be GPIOs
	 * so they are ready for export to user space
	 */
	pinctrl-names = "default";
	pinctrl-0 = <&pinctrl_weim_gpio_1 &pinctrl_weim_gpio_2
	             &pinctrl_weim_gpio_3 &pinctrl_weim_gpio_4
	             &pinctrl_weim_gpio_5
	             &pinctrl_csi_gpio_1
	             &pinctrl_gpio_1
	             &pinctrl_usbh_oc_1 &pinctrl_usbc_id_1
	             &pinctrl_usbc_det_1>;
};

&lcd {
	status = "okay";
};

&mxcfb1 {
	status = "okay";
};

&mxcfb2 {
	status = "okay";
};

&pwm1 {
	status = "okay";
};

&pwm2 {
	status = "okay";
};

&pwm3 {
	status = "okay";
};

&pwm4 {
	status = "okay";
};

&sound_hdmi {
	status = "okay";
};

&uart1 {
	status = "okay";
};

&uart2 {
	status = "okay";
#if 0
	linux,rs485-enabled-at-boot-time;
#endif
};

&uart3 {
	status = "okay";
};

&usbh1 {
	status = "okay";
};

&usbotg {
	status = "okay";
};

/* MMC */
&usdhc1 {
	status = "okay";
};

&weim {
	status = "okay";
	/* weim memory map: 32MB on CS0, 32MB on CS1, 32MB on CS2 */
	ranges = <0 0 0x08000000 0x02000000
	          1 0 0x0a000000 0x02000000
	          2 0 0x0c000000 0x02000000>;
	/* FPGA on CS0 */
	fpga@0,0 {
		compatible = "ntb,flink_eim_driver";
		reg = <0 0 0x00080000>;
		#address-cells = <1>;
		#size-cells = <1>;
		bank-width = <2>;
		fsl,weim-cs-timing = <0x07710081 0x00000100 0x04000000
				0x00000000 0x04000040 0x00000000>;
	};
};