SST49LF008A on amd/db800

[Phani Babu Giddi]

Hello All,

I am planning to use the BIOS chip SST49LF008A instead of SST49LF004B on
AMD's Geode LX 800 development board DB800. Do you think this will work
without changing any optiong in Config.lb for this board. 49LF004B is based
on LPC while 49LF008A is based on FWH. I had to change the part because LPC
interface based chip by SST has been EOLed.

The best way for me would have been to test it and find it out myself but
currently coreboot build is failing on Fedora 8 based system even after
applying the rececent patches and updates to LD.

I am just curious does CS5536 has to be initalized in a differently to be
able to boot from FWH ?

Any idea ?

Regards,
Phani

[Marc Jones]

Phani Babu Giddi wrote:
> Hello All,
>
> I am planning to use the BIOS chip SST49LF008A instead of SST49LF004B on 
> AMD's Geode LX 800 development board DB800. Do you think this will work 
> without changing any optiong in Config.lb http://Config.lb for this 
> board. 49LF004B is based on LPC while 49LF008A is based on FWH. I had to 
> change the part because LPC interface based chip by SST has been EOLed.

If you change the size (8A is 1Mb and 4B is 512KB right?) you will need 
to make an adjustment in the target/../config.lb in order to get the 
correct ROM size.
option ROM_SIZE=1024*1024-36*1024
> The best way for me would have been to test it and find it out myself 
> but currently coreboot build is failing on Fedora 8 based system even 
> after applying the rececent patches and updates to LD.

I will take a closer look at the failure you sent.
> I am just curious does CS5536 has to be initalized in a differently to 
> be able to boot from FWH ?

You will need check cs5536 boot straps are set to FWH. You can check it 
in this MSR:

6.6.2.10 Ball (Pin) Options Control (DIVIL_BALL(PIN)_OPTS)
MSR Address 51400015h
Type R/W
Reset Value 00000x7xh

Marc

[Phani Babu Giddi]

Looks like on the board the Boot Options are hardwired to FWH so all that I
need to do would be to increase the ROM size and it should work. 49LF004B
works both in FWH mode and also in LPC mode.

-Phani

On Fri, Feb 22, 2008 at 2:14 PM, Marc Jones  wrote:
> Phani Babu Giddi wrote:
> > Hello All,
> >
> > I am planning to use the BIOS chip SST49LF008A instead of SST49LF004B on
> > AMD's Geode LX 800 development board DB800. Do you think this will work
> > without changing any optiong in Config.lb http://config.lb/ <
>
> http://Config.lb http://config.lb/> for this
> > board. 49LF004B is based on LPC while 49LF008A is based on FWH. I had to
> > change the part because LPC interface based chip by SST has been EOLed.
>
> If you change the size (8A is 1Mb and 4B is 512KB right?) you will need
> to make an adjustment in the target/../config.lb in order to get the
> correct ROM size.
> option ROM_SIZE=1024*1024-36*1024
> > The best way for me would have been to test it and find it out myself
> > but currently coreboot build is failing on Fedora 8 based system even
> > after applying the rececent patches and updates to LD.
>
> I will take a closer look at the failure you sent.
> > I am just curious does CS5536 has to be initalized in a differently to
> > be able to boot from FWH ?
>
> You will need check cs5536 boot straps are set to FWH. You can check it
> in this MSR:
>
> 6.6.2.10 Ball (Pin) Options Control (DIVIL_BALL(PIN)_OPTS)
> MSR Address 51400015h
> Type R/W
> Reset Value 00000x7xh
>
> Marc