Re: [Etherboot-developers] Q: does xstart work?

[<ke...@us...>]

>> But it's in 32-bit PM at that point.
>
>Hmm.  The LJMPI sure looks like it is in 32PM to me....
>xstart:
>	pushl	%ebp
>	movl	%esp,%ebp
>	pushl	%ebx
>	pushl	%esi
>	pushl	%edi
>	movl	8(%ebp),%eax
>	movl	%eax,_execaddr
>	movl	12(%ebp),%ebx
>	movl	16(%ebp),%ecx	/* bootp record (32bit pointer) */
>	shll	$12,%ecx	/* convert to segment:offset form */
>	shrw	$12,%cx
>	call	_prot_to_real
>	.code16
>	pushl	%ecx		/* bootp record */
>	pushl	%ebx		/* file header */
>	movl	$((RELOC<<12)+(1f-RELOC)),%eax
>	pushl	%eax
>	ADDR32	LJMPI(_execaddr-_start)
>1:
>	addw	$8,%sp		/* XXX or is this 10 in case of a 16bit "ret" 
>*/
>	DATA32 call	_real_to_prot
>	.code32

No, you were right, it's in 16-bit RM at that point and so interprets
the 32-bit word as segment:offset. For a moment I was worried that I was
generating non-compliant tagged images in mknbi. I don't know what
ADDR32 does in .code16 but nothing harmful apparently. Maybe it's needed
for the indirection address.