[U-Boot] [PATCH] at91sam9260/9263: add back up fot the rst(reset controller).

[Stelian Pop]

On Tue, Jun 23, 2009 at 12:46:50PM +0200, Sedji Gaouaou wrote:

> On the boards at91sam9260ek, at91sam9263ek and afed9260, the rstc register was
> set to 0 after being set to 500 ms for the PHY reset.
> Now if back up is enable it will be set to the saved value.

The changelog message is not very clear. What means "if backup is enabled" ?
I don't see anything in the patch which can be enabled or disabled...

I think you meant something like: "Do backup the old reset length and restore
it after the MACB initialisation".

> +	rstc = at91_sys_read(AT91_RSTC_MR);
[...]
>  	/* Restore NRST value */
>  	at91_sys_write(AT91_RSTC_MR, AT91_RSTC_KEY |
> -				     AT91_RSTC_ERSTL | (0x0 << 8) |
> +				     (rstc) |
>  				     AT91_RSTC_URSTEN);

Also, I don't like this: you backup in 'rstc' the _whole_ contents
of the MR register (including for example the URSTEN bit), but on
restore you still construct a bit mask...

In order to be consistent, I would do either:

rstc = at91_sys_read(AT91_RSTC_MR);
...
at91_sys_write(AT91_RSTC_MR, AT91_RSTC_KEY | rstc);

or

rstc = at91_sys_read(AT91_RSTC_MR) & AT91_RSTC_ERSTL;
...
at91_sys_write(AT91_RSTC_MR, AT91_RSTC_KEY | rstc | AT91_RSTC_URSTEN);

Not sure what version would be best though...

Stelian.
-- 
Stelian Pop <stelian at popies.net>