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From: Detlev Zundel <dzu@denx.de>
To: u-boot@lists.denx.de
Subject: [U-Boot] What is CONFIG_HAS_DATAFLASH?
Date: Mon, 08 Mar 2010 17:02:52 +0100	[thread overview]
Message-ID: <m27hpmls2b.fsf@ohwell.denx.de> (raw)
In-Reply-To: <4B916DBD.7050105@freescale.com> (Timur Tabi's message of "Fri, 05 Mar 2010 14:46:53 -0600")

Hi Timur,

> Wolfgang Denk wrote:
>
>>> This doesn't tell me anything.
>> 
>> Hm... What exactly don't you understand here?
>
> Well, I was just wondering what the connection is between DataFlash
> (which is some flash technology that I don't know much about) and the
> md command.

A google hit (second one for me) tells more:

http://www.atmel.com/products/dataflash/default.asp

"... sequential access families ideal for program code, data storage,
Serial EEPROM replacement, and the next generation PC Bios Market".

So it does not fit the "put address on a-bus, get contents on d-bus"
model.

>> Why are plain simple memory accesses not possible on your hardware?
>> Which architecture / CPU is this?
>
> Because on this one chip I'm working on, the designers decided to mux
> the LBC address lines with the video signal from the on-board display
> driver.  No, I'm not kidding about that.  That means that when you're
> using the video display, you can't access flash.

Wow, I knew h/w designers are creative, but _that_ creative ;)

Cheers
  Detlev

-- 
I have always observed that the pretensions of all people are in
exact inverse ratio to their merits; this is one of the axioms of
morals.                            -- Joseph Lagrange
--
DENX Software Engineering GmbH,      MD: Wolfgang Denk & Detlev Zundel
HRB 165235 Munich,  Office: Kirchenstr.5, D-82194 Groebenzell, Germany
Phone: (+49)-8142-66989-40 Fax: (+49)-8142-66989-80 Email: dzu at denx.de

      reply	other threads:[~2010-03-08 16:02 UTC|newest]

Thread overview: 6+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2010-03-05 17:15 [U-Boot] What is CONFIG_HAS_DATAFLASH? Timur Tabi
2010-03-05 19:17 ` Wolfgang Denk
2010-03-05 19:23   ` Timur Tabi
2010-03-05 20:43     ` Wolfgang Denk
2010-03-05 20:46       ` Timur Tabi
2010-03-08 16:02         ` Detlev Zundel [this message]

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