[U-Boot-Users] [patch] add support for "eeprom info"

Wolfgang Denk
2008-01-24T11:31:36Z

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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