From mboxrd@z Thu Jan  1 00:00:00 1970
From: Wolfgang Denk <wd@denx.de>
Date: Thu, 24 Jan 2008 12:31:36 +0100
Subject: [U-Boot-Users] [patch] add support for "eeprom info"
In-Reply-To: Your message of "Thu, 24 Jan 2008 04:13:03 EST."
	<200801240413.04318.vapier@gentoo.org>
Message-ID: <20080124113136.8DADF24788@gemini.denx.de>
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To: u-boot@lists.denx.de

In message <200801240413.04318.vapier@gentoo.org> you wrote:
> 
> > I think you are doing something wrong when you try to use "eeprom" to
> > access "SPI flash" - these are differnt entities...
> 
> let's make sure we're talking about the same thing.  SPI flashes are eeproms 
> that have a SPI interface.  so Spansion's S25FLxxxx, ST's m25pxtmels 
> AT45DBxxxx, Winbond's W25Xxx/W25Pxx, and such.  they need to be erased before 
> writing, are split up into some unit size, etc...  all SPI flashes nowadays 
> conform to the JEDEC standard (JEP106) which allows for querying of 
> manufacturer/device ids so that they can be dynamically detected.  sounds to 
> me like "eeprom" is the correct interface for utilizing these devices.

Sounds to me as if you were talking about flash devices with a SPI bus
interface.

The original SPI eeprom support was implemented som 7+ years ago  for
the  Siemens  CCM  board;  this  is  where  the "CONFIG_SPI" stuff in
common/cmd_eeprom.c  comes  from,  and  this  was  supported  by  the
cpu/mpc8xx/spi.c SPI driver. Note that this was a real EEPROM device,
i.  e.  we just needed spi_read() and spi_write() functions to access
it. No erase, no sectors or any such stuff.

That was an EEPROM - what you have looks like a flash device to me.

Best regards,

Wolfgang Denk

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