[U-Boot] [PATCH] arm: mx23: Fix VDDMEM misconfiguration

Marek Vasut marex at denx.de
Mon Apr 29 05:04:50 CEST 2013


Dear Marek Vasut,

> The VDDMEM ramped up in very weird way as it was horribly misconfigured.
> Instead of setting up VDDMEM in one swipe, let it rise slowly the same
> way as VDDD and VDDA in spl_power_init.c and then only clear ILIMIT before
> memory gets inited. This makes sure the VDDMEM rises sanely, not jumps up
> and down as it did till now.
> 
> The VDDMEM prior to this change did this:
>      2V0____   .--------2V5
> 
>        |    `--'
> 
>  0V____|
> 
> The VDDMEM now does this:
>     2V0_____,-----------2V5
>       /
>  0V__|
> 
> Moreover, VDDIO on MX23 uses 25mV steps while MX28 uses 50mV steps,
> fix this difference too.
> 
> Signed-off-by: Marek Vasut <marex at denx.de>
> Cc: Fabio Estevam <fabio.estevam at freescale.com>
> Cc: Otavio Salvador <otavio at ossystems.com.br>
> Cc: Stefano Babic <sbabic at denx.de>

FYI, with this patch on top of stock 2013.04, the whole boot process :

http://twilight.ponies.cz/MX23-VDDALL.png

Best regards,
Marek Vasut


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