SPI as secondary storage on ARM dev kit?

Hi,

Im trying to build a dev kit for the AT91rm9200, and have linux running
on the final board. However, due to the unavailability of buffers for
the parallel flash, i can only use the SPI DataFlash for storage, and
this is where the OS would reside.

If anyone out here has the At91rm9200-Dk or Ek, can you tell me where
(in parallel or spi flash) is the OS stored, and what is the remaining
flash chip used for? Also,what changes would need to be made to the
arm-linux version provided by Atmel, if the only form of permanent
storage on the chip has to be the spi-flash?

Regards,

Mayank

"Mayank Kaushik" <prehistorictoad2k@yahoo.com> skrev i meddelandet
news:1110020310.345120.192920@f14g2000cwb.googlegroups.com...
> Hi,
>
> Im trying to build a dev kit for the AT91rm9200, and have linux running
> on the final board. However, due to the unavailability of buffers for
> the parallel flash, i can only use the SPI DataFlash for storage, and
> this is where the OS would reside.
>
> If anyone out here has the At91rm9200-Dk or Ek, can you tell me where
> (in parallel or spi flash) is the OS stored, and what is the remaining
> flash chip used for? Also,what changes would need to be made to the
> arm-linux version provided by Atmel, if the only form of permanent
> storage on the chip has to be the spi-flash?
>
> Regards,
>
> Mayank
>

"Mayank Kaushik" <prehistorictoad2k@yahoo.com> skrev i meddelandet
news:1110020310.345120.192920@f14g2000cwb.googlegroups.com...
> Hi,
>
> Im trying to build a dev kit for the AT91rm9200, and have linux running
> on the final board. However, due to the unavailability of buffers for
> the parallel flash, i can only use the SPI DataFlash for storage, and
> this is where the OS would reside.
>
> If anyone out here has the At91rm9200-Dk or Ek, can you tell me where
> (in parallel or spi flash) is the OS stored, and what is the remaining
> flash chip used for? Also,what changes would need to be made to the
> arm-linux version provided by Atmel, if the only form of permanent
> storage on the chip has to be the spi-flash?
>
> Regards,
>
> Mayank
>
AT91RM9200DK
    2 MB Parallel flash
    8 MB Dataflash
    CPU boots from Parallel flash. U-Boot is located in parallel flash
    You typically store the OS on the dataflash and the complete dataflash
can be used.

AT91RM9200EK
    8 MB Parallel flash
    Connector for 8 MB Dataflashcard
    CPU boots from Parallel flash or dataflash card depending on jumper.
    U-Boot is located in parallel flash, but can also exist on the dataflash
card
    You typically store the OS on the same memory as you boot from.
    Have to be careful not to overwrite the u.boot in the dataflash.

The reason for having two chips is to have options.
A typical design would only use one flash chip.
Getting JFFS2 running is typically a little bit easier on parallel flash
Flashing the system during production is typically easier if you have serial
flash.


-- 
Best Regards
Ulf at atmel dot com
These comments are intended to be my own opinion and they
may, or may not be shared by my employer, Atmel Sweden.