[U-Boot] WG: Linux hang

[Siegmund, Jan]

Hi all,
does anybody have an idea for the following problem?

* FPGA is programmed using an overlay
* FPGA writes to SDRAM via the FPGA2SDRAM-bridge
* Linux hangs and the watchdog resets the board (the FPGA stays programmed)
* After the reset and boot, the FPGA is reprogrammed using the same overlay
* Now, the FPGA can write to the SDRAM without a problem

The environment:

*Board:   DE0-NANO-SoC
*U-Boot: 2017.11
*Kernel:  4.14.0-rc7 (review-v4.14-rc7-non-dt-support-v5.1 branch)

The overlay:

/dts-v1/;
/plugin/;

/ {
        fragment at 0 {
                target-path = "/soc/base_fpga_region";
                #address-cells = <1>;
                #size-cells = <1>;
                __overlay__ {
                        #address-cells = <1>;
                        #size-cells = <1>;
                        fpga-bridges = <&fpga_bridge0 &fpga_bridge1>;
                        firmware-name = "foo_base.rbf";

                        fpga-bridge at ffc25080 {
                                compatible = "altr,socfpga-fpga2sdram-bridge";
                                reg = <0xffc25080 0x4>;
                                bridge-enable = <1>;
                        };

                        foo at ff200000 {
                                compatible= "altr,bar";
                                interrupt-parent = <&intc>;
                                interrupts = <0 40 4>;
                        };

                };
        };
};

Thanks