Nitrogen6sx, build 18.06.1, pcie enabled prevents booting

I'm updating our device with nitrogen6sx board to a new owrt version 18.06.1 from owrt 15.05.
I manage to build it, but when I enable pcie the kernel does not boot any more. without pcie it is booting OK, but is of no use. I wonder if new kernel 14.4.63 has some problems with pcie?

A second problem is SDMA not enabled. It complains about sdma-imx6q.bin not found. I put it under
/lib/firmware/imx/sdma/sdma-imx6q.bin

here are my dts/dtsi files:
imx6sx.dtsi

pcie: pcie@0x08000000 {
        compatible = "fsl,imx6sx-pcie", "snps,dw-pcie";
	reg = <0x08ffc000 0x4000>, <0x08f00000 0x80000>;
	reg-names = "dbi", "config";
	#address-cells = <3>;
	#size-cells = <2>;
	device_type = "pci";
	bus-range = <0x00 0xff>;
	ranges = <0x81000000 0 0          0x08f80000 0 0x00010000 
		  0x82000000 0 0x08000000 0x08000000 0 0x00f00000>; 
	num-lanes = <1>;
	interrupts = <GIC_SPI 120 IRQ_TYPE_LEVEL_HIGH>;
	interrupt-names = "msi";
	#interrupt-cells = <1>;
	clocks = <&clks IMX6SX_CLK_PCIE_AXI>,
            	<&clks IMX6SX_CLK_LVDS1_OUT>,
            	<&clks IMX6SX_CLK_PCIE_REF_125M>,
            	<&clks IMX6SX_CLK_DISPLAY_AXI>;
	clock-names = "pcie", "pcie_bus", "pcie_phy", "pcie_inbound_axi";
			pcie-phy-supply = <&reg_pcie>;
	status = "okay";
};
sdma: sdma@020ec000 {
	compatible = "fsl,imx6sx-sdma", "fsl,imx6q-sdma";
	reg = <0x020ec000 0x4000>;
	interrupts = <GIC_SPI 2 IRQ_TYPE_LEVEL_HIGH>;
	clocks = <&clks IMX6SX_CLK_SDMA>,	 
                      <&clks IMX6SX_CLK_SDMA>;
	clock-names = "ipg", "ahb";
	#dma-cells = <3>;
	/* imx6sx reuses imx6q sdma firmware */
	fsl,sdma-ram-script-name = "imx/sdma/sdma-imx6q.bin";
};

imx6sx-nitrogen6sx.dts

&pcie {
	pinctrl-names = "default";
	pinctrl-0 = <&pinctrl_pcie>;
	reset-gpio = <&gpio4 10 GPIO_ACTIVE_LOW>;
	status = "disabled";
};
pinctrl_pcie: pciegrp {
	fsl,pins = <
		MX6SX_PAD_NAND_DATA05__GPIO4_IO_9	0xb0b0
		MX6SX_PAD_NAND_DATA06__GPIO4_IO_10	0xb0b0
		MX6SX_PAD_NAND_DATA07__GPIO4_IO_11	0xb0b0
	>;
};

Note: because a limited space I copied only relevant pcie and sdma entry.

I updated OpenWRT to release 18.06.2 which came with kernel 14.4.95. This fixed SDMA problem.
PCIE problem is still there.