[LinuxBIOS] Comes up but cant see CMOS prompt or options

Richard Smith smithbone at gmail.com
Fri Jul 28 01:42:43 CEST 2006

> After groping around for awhile, with no text output from LB, I came upon
> the nice document  on the website under "port guides"/"VGA support" which
> detailed the procedure for combining the quartet.rom file with a vga.rom
> file and this allowed me to see some text output from the LB printk_notice
> messages, but none of the printk_notice messages come before the call to
> dev_initialize() which is called late in the hardwaremain() routine.  BTW
> there is a coment in the beginning of hardwaremain() that says:
>  /* displayinit MUST PRECEDE ALL PRINTK! */
>         console_init();

Ah.. You are talking linuxbios printk.  Sorry I thought you were
talking kernel printk.  The reference to early printk confused me.

Are you getting messges on the serial port?  Its not clear to me.

> But this call does not seem to do all that's needed to get
> printk(printk_notice) messages to come to the console.

You are talking video console here not serial console right?

> My goal was to play with the boot order, to boot from CD, to try to get
> Linux to boot from LB.  I see that there is a reference to  cmos.layout in
> src/config/Config.lb which  shows  option_table.c as dependent on
> cmos.layout,  so  if an acceptable way to set boot order etc is to hand edit
> the cmos.layout file then that's fine, I just need understand it better.
> This file has the following snipet:
> #start-bit length  config config-ID    name

Yes. Typically everything in linuxbios is pre-set in the config files(s).

> 416          4       e       7        boot_first
> 420          4       e       7        boot_second
> 424          4       e       7        boot_third
> But I'm not sure what to do here, any suggestions?  Should I edit this file?
>  How do I make the CD or floppy the first boot?  Is there documentation on
> this?

Doubtfull.  Docs are scarce round these parts.  The place to look
would be in the FILO code.  Stefan (I think it was Stefan) reciently
added the capability to have some GRUBlike options on booting.

Sorry I can't be more descriptive but I've not played with it yet.

> Note that the mainboard/.../Options.lb file has HAVE_OPTION_TABLE=1
> so I assume this means it's using the cmos.layout file.  Is this true?

Yes.  However, we don't do much with that table.
grepping the source for HAVE_OPTION_TABLE shows its used in
mc146818rtc.c and by the Intel 82801ca southbridge code for checking
if the previous boot failed and falling back to the good image.

So unless FILO is using those options then I don't think they do anything.

Richard A. Smith

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