Does Linux have serial flash drivers?

Does Linux have serial flash drivers?

[colin]

Hi all,
I have looked for several days. No serial flash driver can be found in Linux
source tree.
Does Linux totally give up supporting serial flash?
Is it easy to write a chip driver of serial flash for MTD?

Regards,
Colin

Re: Does Linux have serial flash drivers?

[Peter Menzebach]

colin wrote:
> Hi all,
> I have looked for several days. No serial flash driver can be found in Linux
> source tree.
> Does Linux totally give up supporting serial flash?
> Is it easy to write a chip driver of serial flash for MTD?

Hi Colin,
the at91rm9200dk board has a Atmel serial dataflash:
http://maxim.org.za/AT91RM9200/2.6/

There is a linux mtd driver and jffs2 support.


Best regards
Peter

-- 
Peter Menzebach
Menzebach und Wolff IT-Consulting GbR
Phone +49 751 355 387 1

Re: Does Linux have serial flash drivers?

[colin]

Hi Peter,
I noticed this driver before.
But I think it is strnage that there are many serial Flash chips in the
world but there is no any corresponding mtd driver in Linux kernel source
tree.
What's the reason of this?

Regards,
Colin


----- Original Message ----- 
From: "Peter Menzebach" <pm-armlist@mw-itcon.de>
To: "colin" <colin@realtek.com.tw>
Cc: <linux-mtd@lists.infradead.org>
Sent: Tuesday, December 13, 2005 4:46 PM
Subject: Re: Does Linux have serial flash drivers?


> colin wrote:
> > Hi all,
> > I have looked for several days. No serial flash driver can be found in
Linux
> > source tree.
> > Does Linux totally give up supporting serial flash?
> > Is it easy to write a chip driver of serial flash for MTD?
>
> Hi Colin,
> the at91rm9200dk board has a Atmel serial dataflash:
> http://maxim.org.za/AT91RM9200/2.6/
>
> There is a linux mtd driver and jffs2 support.
>
>
> Best regards
> Peter
>
> -- 
> Peter Menzebach
> Menzebach und Wolff IT-Consulting GbR
> Phone +49 751 355 387 1

Re: Does Linux have serial flash drivers?

[Peter Menzebach]

colin wrote:
> Hi Peter,
> I noticed this driver before.
> But I think it is strnage that there are many serial Flash chips in the
> world but there is no any corresponding mtd driver in Linux kernel source
> tree.
> What's the reason of this?
> 
> Regards,
> Colin

Maybe, because most boards will then need 2 flashs with different
interfaces. Afaik only the Atmel at91... can boot directly from serial
dataflash due to it's internal ROM services.

Even this seems to be not a mainstream way to boot, because the
maintainer of the available bootloader (u-boot) declared that way to
boot deprecated.

In our case it was fine, because this allowed to reduce the size of the
board.

Another reason might be a hen/egg problem. (driver/first board available)

Best regards
Peter

-- 
Peter Menzebach
Menzebach und Wolff IT-Consulting GbR
Phone +49 751 355 387 1

Re: Does Linux have serial flash drivers?

[David Jander]

On Wednesday 14 December 2005 09:20, Peter Menzebach wrote:
>[...]
> Maybe, because most boards will then need 2 flashs with different
> interfaces. Afaik only the Atmel at91... can boot directly from serial

This is actually quite conceivable. Have a small parallel NOR-Flash for 
boot-loader+kernel, and a huge serial nand-flash (cheaper per-Mb) as flash 
disk.
Btw, I was wondering the same.
AFAICR, there is QSlinux (do they still exist today?), that made a serial 
flash driver (via SPI) and used serial data-flash as fs.

Greetings,

-- 
David Jander