Index: rombios.c
===================================================================
RCS file: /cvsroot/bochs/bochs/bios/rombios.c,v
retrieving revision 1.209
diff -c -r1.209 rombios.c
*** rombios.c	2 Jun 2008 20:08:10 -0000	1.209
--- rombios.c	8 Dec 2008 10:09:53 -0000
***************
*** 10194,10199 ****
--- 10194,10223 ----
    mov  ax, 2[bx]
    cmp  ax, #0x506e
    jne  no_bev
+ 
+   mov  ax, 0x16[bx] ;; 0x16 is the offset of Boot Connection Vector
+   cmp  ax, #0x0000
+   je   no_bcv
+ 
+   ;; Option ROM has BCV. Run it now.
+   push cx       ;; Push seg
+   push ax       ;; Push offset
+ 
+   ;; Point ES:DI at "$PnP", which tells the ROM that we are a PnP BIOS.
+   mov  bx, #0xf000
+   mov  es, bx
+   lea  di, pnp_string
+   /* jump to BCV function entry pointer */
+   mov  bp, sp   ;; Call ROM BCV routine using seg:off on stack
+   db   0xff     ;; call_far ss:[bp+0]
+   db   0x5e
+   db   0
+   cli           ;; In case expansion ROM BIOS turns IF on
+   add  sp, #2   ;; Pop offset value
+   pop  cx       ;; Pop seg value (restore CX)
+   ja   no_bev
+ 
+ no_bcv:
    mov  ax, 0x1a[bx] ;; 0x1A is also the offset into the expansion header of...
    cmp  ax, #0x0000  ;; the Bootstrap Entry Vector, or zero if there is none.
    je   no_bev