MBR: shave off another byte

Yet another byte bites the dust...

diff --git a/mbr/mbr.S b/mbr/mbr.S
index 0822b53..2a318be 100644 (file)
--- a/mbr/mbr.S
+++ b/mbr/mbr.S
@@ -93,12 +93,13 @@ next:
        int     $0x13
        andw    $0x3f, %cx      /* Sector count */
        pushw   %cx             /* Save sectors on the stack */
-       xorw    %ax, %ax
-       pushw   %ax             /* High word of sectors/cylinder */
-       movb    %dh, %al        /* dh = number of heads */
-       incw    %ax             /* From 0-based to count */
+       movzbw  %dh, %ax        /* dh = max head */
+       incw    %ax             /* From 0-based max to count */
        mulw    %cx             /* Heads*sectors -> sectors per cylinder */
-       pushw   %ax             /* Save sectors/cylinder on the stack */
+
+       /* Save sectors/cylinder on the stack */
+       pushw   %dx             /* High word */
+       pushw   %ax             /* Low word */
 
        xorl    %eax, %eax      /* Base */
        cdq                     /* Root (%edx <- 0) */