Changeset 21618 in vbox

Timestamp:

Jul 15, 2009 3:42:52 PM (16 years ago)

Author:

vboxsync

svn:sync-xref-src-repo-rev:

50140

Message:

BIOS: Stop PCI BIOS from destroying edx/ecx. Fixes IBMIDECD.SYS driver.

File:

• trunk/src/VBox/Devices/PC/BIOS/rombios.c (modified) (5 diffs)

trunk/src/VBox/Devices/PC/BIOS/rombios.c

@@ -10039 +10039 @@
   push esi
   push edi
+  push edx
   cmp al, #0x02
   jne pci_real_f03
@@ -10081 +10082 @@
   cmp ebx, #0x10000
   jne pci_real_devloop2
-  mov dx, cx
-  shr ecx, #16
   mov ax, #0x8603
   jmp pci_real_fail
@@ -10196 +10195 @@
   mov ah, #0x81
 pci_real_fail:
+  pop edx
   pop edi
   pop esi
@@ -10202 +10202 @@
 pci_real_ok:
   xor ah, ah
+  pop edx
   pop edi
   pop esi
@@ -10207 +10208 @@
   ret
 
+;; prepare from reading the PCI config space; on input:
+;; bx = bus/dev/fn
+;; di = offset into config space header
+;; destroys eax and may modify di
 pci_real_select_reg:
   push dx