qemu/qemu-bios-bigger-roms.patch
2009-04-02 03:51:08 +00:00

53 lines
712 B
Diff

diff --git a/bios/rombios.c b/bios/rombios.c
index c4f6ccd..c4bfe60 100644
--- a/bios/rombios.c
+++ b/bios/rombios.c
@@ -10196,22 +10196,43 @@ no_serial:
ret
rom_checksum:
- push ax
- push bx
- push cx
+ pusha
+ push ds
+
xor ax, ax
xor bx, bx
xor cx, cx
+ xor dx, dx
+
mov ch, [2]
shl cx, #1
+
+ jnc checksum_loop
+ xchg dx, cx
+ dec cx
+
checksum_loop:
add al, [bx]
inc bx
loop checksum_loop
+
+ test dx, dx
+ je checksum_out
+
+ add al, [bx]
+ mov cx, dx
+ mov dx, ds
+ add dh, #0x10
+ mov ds, dx
+ xor dx, dx
+ xor bx, bx
+
+ jmp checksum_loop
+
+checksum_out:
and al, #0xff
- pop cx
- pop bx
- pop ax
+ pop ds
+ popa
ret