[U-Boot] Cyclone 5 U-boot 2015.10

[Marek Vasut <marex@denx.de>]

On Tuesday, November 17, 2015 at 02:08:21 PM, Simon Brown wrote:
> Hi,

Hi,

> I've been in discussion with Marek on this issue, and he suggested I post
> to the u-boot mailing list.
> 
> I've git cloned uboot 2015.10 and checked it out in my own branch.  I
> wasn't about to submit anything back, but this way I hopefully wouldn't
> break anything if I did!
> 
> I've created a new board, "Axim".  I've setup the DTS, Kconfig, defconfig
> files etc similar to the Atlas board addition, and things are compiling
> ok.  However, when I run U-boot it gets to a relatively early point and
> then says "### ERROR ### Please reset the board ###".  I can't see it say
> this ,as it no longer talks to the UART, but I can see that it points to
> the memory address containing this string in the debugger, so assume that's
> what it prints out, before entering an endless loop.
> 
> My setup is slightly odd, in that I need to get U-boot running before I can
> configure an SD card.

Why ?

> This means I'm programming my FPGA via JTAG, then
> loading the preloader with the ARM DS-5 debugger via JTAG and running it.

OK, so what I suggest you do (to make things easy) is:

1) edit arch/arm/mach-socfpga/spl.c
2) locate board_init_f()
3) Add the following code all the way to the end of board_init_f() (which is,
   incidentally, at the end of the file):
   asm volatile("x: b x");

This will make sure that the SPL starts spinning in an endless loop at this 
point. Once you load this modified SPL with your debugger, it will init the
hardware, but it won't do anything funny anymore.

So once your hardware is running, load U-Boot (u-boot-dtb.bin) to 0x01000040
and execute it from that address. This should get you the prompt.

> I get output on the UART (via FPGA pins), to my PC, to suggest that all is
> running well.  I can then upload my u-boot.img file to the preloader using
> Ymodem (preloader configured to accept this), and I can run U-boot.
> 
> Before I was using the preconfigured 2013.01.01 U-boot as provided on
> Rocketboards.org, but since we are using the KSZ9031 chip for our PHY felt
> I needed a newer version to support this.  But 2013.01.01 runs ok, and I
> can get to the U-boot prompt on the UART, whereas 2015 hangs.
> 
> Any clues gratefully received.

Try the above method, hope that helps.

Best regards,
Marek Vasut