From mboxrd@z Thu Jan  1 00:00:00 1970
From: Ingo van Lil <inguin@gmx.de>
Date: Sun, 04 Oct 2009 13:15:57 +0200
Subject: [U-Boot] [PATCH] CFI Driver: Reset watchdog timer after each
 flash operation
In-Reply-To: <20091003232910.BEF2F832E408@gemini.denx.de>
References: <20091002103417.GA9767@zaphod.peppercon.de>
	<200910021306.38589.sr@denx.de> <4AC5EE3B.5090200@gmx.de>
	<20091003232910.BEF2F832E408@gemini.denx.de>
Message-ID: <4AC883ED.8050006@gmx.de>
List-Id: <u-boot.lists.denx.de>
MIME-Version: 1.0
Content-Type: text/plain; charset="us-ascii"
Content-Transfer-Encoding: 7bit
To: u-boot@lists.denx.de

On 10/04/2009 01:29 AM, Wolfgang Denk wrote:

> No, not an exception, but the reference implementation. I cannot help
> it that most other architectures / SoCs don;t care much.

Well, if such an uncommon side-effect is expected of a function with a 
well-known name it should at least be prominently documented. I like 
Mike's suggestion to have a central udelay() implementation for that; 
I'm gonna try to whip up a patch tomorrow.


>> I'm using an Atmel AT91-based custom board, and the udelay() function
>> can be found in cpu/arm926ejs/at91/timer.c. Unfortunately there's no
>> central udelay() implementation in lib_arm.
>
> Guess nobody attempted to use a WD on such a system before.

You hardly have a choice: After reset the AT91's watchdog timer runs at 
maximum period (15 seconds), and the control register is one-time 
writable. If you disable the watchdog in u-boot there's no way to 
re-enable it later in the OS.

Regards,
Ingo