[LinuxBIOS] Epia-M compilation fails

Nick Barker nick.barker9 at btinternet.com
Fri Oct 14 18:51:59 CEST 2005

Ok got to the stage where Epia-m is booting linux, though with lots of
things broken and running only to the serial port (i.e. no vga yet).

I have a couple of issues:

To get the code to run the cpu initialisation sequences I've had to change
the epia-m Config.lb from


   chip cpu/via/model_centaur



   device apic_cluster 0 on
	chip cpu/via/model_centaur
		device apic 0 on end

This is so that the code in the northbridge has appropriate device
structures to work with. Now this processor does not have a lapic, so this
construct seems bizare to me. Is there a more appropriate construct where no
lapic is present?

A quick grep shows that there are several other motherboards which use the
same style of configuartion in their Config.lb and their northbridge code.
Do these need changing as well?

Additionally 'src/arch/i386/lib/cpu.c' needs changing to support the case
where no lapic is present:

in function cpu_initialize there needs to be a conditional around some lines
as follows:

	if (cpu->path.u.apic.apic_id != lapicid()) {
		printk_err("CPU .....
            // return without setting ...
      } else {

and a similar condition around the closing brace a few lines later

Nick Barker

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