Re: [Qemu-devel] Darwin/Mac OS X Port

[Pierre d'Herbemont]

Hi!

On 19 févr. 04, at 21:45, Daniel J. Guinan wrote:

> I have been looking and tinkering with your OS X port and was not able 
> to get any translation working until I fudged with a couple of things. 
>  The most important of those is in vl.c -> search for valloc() -> you 
> will see an attempt to allocate *page_size x all memory* change it to 
> *all memory* and you will be on your way.  Here is a log from my 
> changes:

thanks ;) This one would be helpful.

> COMMAND LINE:  qemu -d -L ../pc-bios -nographic --kernel bzImage 
> --append "console=ttyS0 root=/dev/hda sb=0x220,5,1,5 ide2=noprobe 
> ide3=noprobe ide4=noprobe ide5=noprobe" linux.img

thanks for this one also ;)

Also after reading the output code again, and without knowing x86 
assembly, I have been wondering myself about why does the ljmp change 
the EIP to 0x0 and fetch code from 0xf000. So there might be an issue 
here.

See:
[snip]
> IN:
> 0x000ffff0:  ljmp   0xf000,0xe05b
>
> AFTER FLAGS OPT:
> 0x0000: movl_T0_im 0xf000
> 0x0001: movl_T1_im 0xe05b
> 0x0002: movl_seg_T0_vm 0xb0
> 0x0003: movl_T0_T1
> 0x0004: jmp_T0
> 0x0005: movl_T0_0
> 0x0006: exit_tb
> 0x0007: end
>
> OUT: [size=60]
> 0x002071f0:  lis        r2,184
> 0x002071f4:  lwz        r24,-28096(r2)
> 0x002071f8:  lis        r2,184
> 0x002071fc:  lwz        r25,-28096(r2)
> 0x00207200:  lis        r2,184
> 0x00207204:  clrlwi     r0,r24,16
> 0x00207208:  lwz        r2,-28096(r2)
> 0x0020720c:  mr r9,r27
> 0x00207210:  stwux      r0,r9,r2
> 0x00207214:  rlwinm     r0,r0,4,0,27
> 0x00207218:  stw        r0,4(r9)
> 0x0020721c:  mr r24,r25
> 0x00207220:  stw        r24,32(r27)
> 0x00207224:  li r24,0
> 0x00207228:  blr
>
> Trace 0x002071f0 [0x000ffff0]
> EAX=00000000 EBX=00000000 ECX=00000000 EDX=00000600
> ESI=00000000 EDI=00000000 EBP=00000000 ESP=00000000
> EIP=00000000 EFL=00000002 [-------]    CPL=0 II=0
> ES =0000 00000000 0000ffff 00000000
> CS =f000 000f0000 0000ffff 00000000
> SS =0000 00000000 0000ffff 00000000
> DS =0000 00000000 0000ffff 00000000
> FS =0000 00000000 0000ffff 00000000
> GS =0000 00000000 0000ffff 00000000
> LDT=0000 00000000 0000ffff 00008000
> TR =0000 00000000 0000ffff 00008000
> GDT=     00000000 0000ffff
> IDT=     00000000 0000ffff
> CR0=60000010 CR2=00000000 CR3=00000000 CR4=00000000
> CCS=00000000 CCD=00000000 CCO=EFLAGS
> ----------------

here should be 0x000fe05b or something like that...

> IN:
> 0x000f0000:  pushw  %bp
> 0x000f0001:  movw   %sp,%bp
> 0x000f0003:  pushw  %ax
> 0x000f0004:  pushw  %cx
> 0x000f0005:  pushw  %es
> 0x000f0006:  pushw  %di
> 0x000f0007:  movw   0xa(bp),%cx
> 0x000f000a:  cmpw   $0x0,%cx
> 0x000f000d:  je     0xf001f
>
> AFTER FLAGS OPT:
> 0x0000: movl_T0_EBP
> 0x0001: movl_A0_ESP
> [snip]
>
> I am still fiddling around with it and trying to wrap my head around 
> what Fabrice has done, but will post a diff if anyone wants it.

I am interested about your patch.

Thanks again,

Pierre