[LinuxBIOS] 4mb Flash

Hi Everyone,

I recently purchased a VIA Epia MII 12000 with the intentions of using
LinuxBIOS but I am having a slight problem using a 4mb bios.  According to
VIA this board does indeed support a 4mb flash
(http://www.via.com.tw/en/products/mainboards/motherboards.jsp?motherboard_id...).
 I also purchased a 4mb SST39SF040 bios chip which according to the manual
is in fact 4mb (http://www.sst.com/downloads/datasheet/S71147.pdf).
However, when I run flashrom it produces the following output:

./flashrom
Calibrating delay loop... ok
No LinuxBIOS table found.
Found chipset "VT8235": Enabling flash write... OK.
Found board "VIA EPIA M/MII/...": Enabling flash write... OK.
SST39SF040 found at physical address: 0xfff80000
Flash part is SST39SF040 (512 KB)
OK, only ENABLING flash write, but NOT FLASHING.

As you can see, flashrom thinks this is only a 512KB chip.  Upon further
inspection I found that total_size is defined as 512 in flashchips.c.  I
tried increasing this number to 4096 but then flashrom reported invalid
(0xFF) manufacturer and product IDs.  Can someone please shed some light
on this situation for me?  Am I missing something?

Thanks
William

[Peter Stuge]

On Thu, May 17, 2007 at 10:21:43PM -0400, [e-mail] wrote:
> ./flashrom

[..]
> OK, only ENABLING flash write, but NOT FLASHING.
>
> As you can see, flashrom thinks this is only a 512KB chip.

Flash chip size is measured in bits, 4Mbit=512kbyte.

You have the correct chip for the board. The EPIA-M(II) doesn't
support larger chips than 4Mb.

Use flashrom -w to actually write to the chip.

//Peter

Peter,

Wow, I really feel like an idiot.  I read 4Mb and NOT 4Mbit.  Anyways,
thanks for such a speedy response.

William

On Thu, May 17, 2007 10:28 pm, Peter Stuge wrote:
> On Thu, May 17, 2007 at 10:21:43PM -0400, [e-mail] wrote:
> > ./flashrom
>
> [..]
> > OK, only ENABLING flash write, but NOT FLASHING.
> >
> > As you can see, flashrom thinks this is only a 512KB chip.
>
> Flash chip size is measured in bits, 4Mbit=512kbyte.
>
> You have the correct chip for the board. The EPIA-M(II) doesn't
> support larger chips than 4Mb.
>
> Use flashrom -w to actually write to the chip.
>
> //Peter

[Jeremy Jackson]

On Thu, 2007-05-17 at 22:38 -0400, [e-mail] wrote:
> Peter,
>
> Wow, I really feel like an idiot.  I read 4Mb and NOT 4Mbit.  Anyways,
> thanks for such a speedy response.

you can say 4MB for megabytes, or to be more exact use the new 4MiB for
4*1024*1024 bytes.  the disk drive people say M = 1000 * 1000 so Mi is
better for us.

[Jody Belka]

On Thu, May 17, 2007 at 10:21:43PM -0400, [e-mail] wrote:
> I also purchased a 4mb SST39SF040 bios chip which according to the manual
> is in fact 4mb (http://www.sst.com/downloads/datasheet/S71147.pdf).

[...]
> Flash part is SST39SF040 (512 KB)

[...]
> As you can see, flashrom thinks this is only a 512KB chip.

[...]
> Can someone please shed some light
> on this situation for me?  Am I missing something?

yep. flashrom is completely correct. The chip is 4 mega*bits*, which is the
same as 512 kilo*bytes*.

J