[U-Boot] register polling from HUSH parser?

[Wolfgang Denk]

Dear Masahiro,

In message <CAK7LNATy2wfxErhQTaPtJ+YREPLttD9oGDr3kZff7TXBD0BCVQ at mail.gmail.com> you wrote:
> 
> Is there any good way to poll a certain register
> in a HUSH parser script?

Yes, there is :-)

> For example, I want to wait
> until the register value of 0x50000000 becomes 1
> in a HUSH script.

OK...

> The pseudo code would be like this:
> 
> while   readl(0x50000000) != 1
> do
>        ;
> done;

And in HUSH:

while itest *50000000 != 1
do
	...
done

> I wish there were a command that
> stores a value of a given address into an environment,
> but I have no idea about that.

Try "help setexpr".  If you want to store the value as is, just apply
a null operation, like

	=> setexp foo *50000000 | 0
	=> printenv foo


Hope this helps...

Best regards,

Wolfgang Denk

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