From: Lucas Stach <dev@lynxeye.de>
Date: Fri, 25 Jan 2013 23:11:37 +0100
Subject: [U-Boot] [PATCH 04/11] tegra20: switch over tamonten platform
 to use tablebased pinmux
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	<5103015F.6080508@nvidia.com>
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Am Freitag, den 25.01.2013, 14:04 -0800 schrieb Stephen Warren:
> On 01/24/2013 08:48 AM, Lucas Stach wrote:
> > Init pinmux in one shot, in order to avoid any conflicts.
> 
> > diff --git a/board/avionic-design/common/tamonten.c b/board/avionic-design/common/tamonten.c
> 
> > +static struct pingroup_config tamonten_pinmux[] = {
> > +	PINMUX_ENTRY(ATA, IDE, NORMAL, NORMAL), /* GPIO */
> > +	PINMUX_ENTRY(ATB, SDIO4, NORMAL, NORMAL), /* MMC */
> ...
> 
> I believe this initializes every single pingroup on the SoC to
> something. In order to prevent any behavior changes, wouldn't it be
> better to first fill in this table only with entries that achieve the
> same pinmux programming that used to be performed by the C code you're
> removing? Then, a separate later patch could fill in missing items in
> the pinmux table. I think that'd end up being much safer and easier to
> validate.
> 

As I wrote in the cover letter this initializes the pinmux to the same
values the Linux kernel uses. I don't consider it a safer approach to
pull out the old pinmux from the C Code and then later building a
conflict free full muxtable out of this.

However I made sure to go through the C Code to see which pads need to
be un-tristated. At that time I cross-checked the table with the
functions used by the C Code. But as a human I'm not safe from mistakes.

Regards,
Lucas