[LinuxBIOS] flashrom geodelx patch

[Ingmar Schraub]

Add support for AMD Geode LX / CS5536 to the flashrom utility.

Signed-off-by: Ingmar Schraub

---

regards,

Ingmar

[ron minnich]

I think we ought to have a comment in here about what this does. It's
a great patch, and very nice to have, but can you describe what is
going on.

thanks
ron

[Ingmar Schraub]

Most of it is already documented at
http://wiki.laptop.org/go/Flashing_LinuxBIOS where I took the
information from. The link came from Marc Jones and you provided there
rdmsr/wrmsr.

I got the chipset identifier from lspci from my Alix board and added it.
I've tested it with my Alix board where I have a SST49LF040B flash chip.

Well, maybe I've done something wrong... You can tell me.

What did you/or other developers do when you added support for any other
chipset? As I said before, I am completely new to LB...

regards, Ingmar

ron minnich wrote:
> I think we ought to have a comment in here about what this does. It's
> a great patch, and very nice to have, but can you describe what is
> going on.
>
> thanks
> ron

[Tom Sylla]

This patch is not quite correct.

The MSR being written is RCONF_DEFAULT_MSR (0x1808). That MSR includes
SYSTOP (where RAM ends). That should be dynamic depending on the
amount of RAM in the system, you can't really just smash in a fixed
value. The correct thing to do is to read the MSR, clear WP of the
ROMRP field, and write it back. Doing it this way would make it proper
and much cleaner (and self-documented).

(if anyone wonders what the fields mean, just read the LX databook)

On 8/15/07, Ingmar Schraub  wrote:
> Add support for AMD Geode LX / CS5536 to the flashrom utility.
>
> Signed-off-by: Ingmar Schraub
>
> regards,
>
> Ingmar

[Ingmar Schraub]

Okay, I fully agree with you. That means, the patch I sent, should not
be applied until this has been corrected in a proper way!!

Tom Sylla wrote:
> This patch is not quite correct.
>
> The MSR being written is RCONF_DEFAULT_MSR (0x1808). That MSR includes
> SYSTOP (where RAM ends). That should be dynamic depending on the
> amount of RAM in the system, you can't really just smash in a fixed
> value. The correct thing to do is to read the MSR, clear WP of the
> ROMRP field, and write it back. Doing it this way would make it proper
> and much cleaner (and self-documented).
>
> (if anyone wonders what the fields mean, just read the LX databook)
>
> On 8/15/07, Ingmar Schraub  wrote:
> > Add support for AMD Geode LX / CS5536 to the flashrom utility.
> >
> > Signed-off-by: Ingmar Schraub
> >
> > regards,
> >
> > Ingmar

[Marc Jones]

Tom Sylla wrote:
> This patch is not quite correct.
>
> The MSR being written is RCONF_DEFAULT_MSR (0x1808). That MSR includes
> SYSTOP (where RAM ends). That should be dynamic depending on the
> amount of RAM in the system, you can't really just smash in a fixed
> value. The correct thing to do is to read the MSR, clear WP of the
> ROMRP field, and write it back. Doing it this way would make it proper
> and much cleaner (and self-documented).
>
> (if anyone wonders what the fields mean, just read the LX databook)

Thanks Tom! Couldn't put it better myself. :)

Marc