[LinuxBIOS] [RFC] Call for Action: LinuxBIOS foundations

Carl-Daniel Hailfinger c-d.hailfinger.devel.2006 at gmx.net
Wed Aug 29 17:02:11 CEST 2007

On 29.08.2007 16:47, Uwe Hermann wrote:
> On Tue, Aug 28, 2007 at 08:17:45PM +0200, Carl-Daniel Hailfinger wrote:
>> Think of all the MCP55 boards. RAM works. North- and southbridge are
>> supported. The "little things" are what keep us from supporting them
>> completely. A generic MCP55 port which loads the payload (additional
>> board init etc.) over serial can be the ideal starting point.
> Why? I don't really see a use for this. If someone is able to run such
> a payload, build LinuxBIOS, test patches etc. it's not much additional
> work to just add proper support for the board in the first place.
> No need for such a "test-payload", I think.

The "you can always reflash the old BIOS" feeling gives confidence to
porters who might not have a replacement chip handy.

>> Maybe publish an article on lwn/slashdot/whatever about flashrom? You'd
>> have to make sure people merge MAC addresses and other stuff from the
>> old into the new image, though, otherwise we'll have a load of boards
>> with the same MAC address and quite a few of them may have
>> 00:00:00:00:00:00, resulting in malfunction of some switches, network
>> stacks etc.
> Can you elaborate? Where is the MAC address stored? On which boards?
> I doubt that all boards out there do this. What happens if you download
> a BIOS image from $VENDOR website? Does the flasher contain special code
> to deal with the MAC address?

The MAC address is stored in flash for almost all CK804/MCP55 boards.
All of these boards flashed with LB probably have the same MAC address.
See src/southbridge/nvidia/ck804/romstrap.inc and
src/southbridge/nvidia/mcp55/romstrap.inc for details. On some of these
boards, the MAC address is stored in a separate EEPROM, but you can't
count on that.


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