From mboxrd@z Thu Jan  1 00:00:00 1970
From: Scott Wood <scottwood@freescale.com>
Date: Wed, 04 Feb 2009 14:45:11 -0600
Subject: [U-Boot] [PATCH] nand_base: Add timeout for NAND reset command
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Peter Tyser wrote:
> The 25ns was calculated based on the addition of trp and trhoh from the
> Micron MT29F8G08 datasheet.  Based on the timing diagram for a "Read
> Status" cycle I thought this would be the minimum cycle time needed to
> read the chip's status.  Other chips (ST, Samsung) I glanced at had > 25
> ns read status times as well.
> 
> I had tried using get_timer() (I believe nand_wait() would have been
> perfect to use), but that didn't work due to interrupts being disabled
> when NAND is probed.  I didn't consider using get_ticks()...  That seems
> much better.  Is get_ticks() available for all platforms when NAND is
> initialized?

Probably, but who knows what weirdness is out there.

> Assuming get_ticks() is available for all platforms, would you prefer I:
> 1. re-do the patch using get_ticks()
> 2. update nand_wait() to use get_ticks instead of get_timer() and use it

#2 looks better.

-Scott