[meta-xilinx] u-boot SPL boot fail with CONFIG_HW_WATCHDOG

[Mike Looijmans]

On 03/26/2014 10:26 AM, Mike Looijmans wrote:
> For a custom board with an external GPIO controlled watchdog, I tried adding
> watchdog support to u-boot. (using master-next from u-boot-xlnx)
>
> The watchdog support works (I'm using a LED for now until the real hardware
> arrives), I just defined CONFIG_HW_WATCHDOG and added a reset routine that
> bitbangs the GPIO registers which should feed the watchdog. I can see the LED
> blink, so the GPIO routines appear to work well.
>
> However, this causes the board to fail to boot the kernel.
>
> If I define CONFIG_HW_WATCHDOG and leave the hw_watchdog_*() methods empty, so
> that there SHOULD be no effect, the kernel will not boot and the system hangs
> immediately after "Starting kernel...". Removing the define from the board
> config makes that problem go away. If I call the GPIO routines from the board
> code in u-boot, the kernel still boots fine too.
>
> The zynq has no support for any WATCHDOG yet, so I have no idea what could
> cause this behaviour.
>
> I'm looking for a possible cause. Any ideas?

I've found a workaround: Setting CHUNKSZ to 16MB fixes the issue. Apparently 
there's a problem in a chunked memcpy routine?

Mike.



Met vriendelijke groet / kind regards,

Mike Looijmans

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