--- grub-0.97.orig/stage2/asm.S 2004-06-19 18:55:22.000000000 +0200 +++ grub-0.97/stage2/asm.S 2006-04-21 11:10:52.000000000 +0200 @@ -1651,7 +1651,29 @@ jnz 3f ret -3: /* use keyboard controller */ +3: /* + * try to switch gateA20 using PORT92, the "Fast A20 and Init" + * register + */ + mov $0x92, %dx + inb %dx, %al + /* skip the port92 code if it's unimplemented (read returns 0xff) */ + cmpb $0xff, %al + jz 6f + + /* set or clear bit1, the ALT_A20_GATE bit */ + movb 4(%esp), %ah + testb %ah, %ah + jz 4f + orb $2, %al + jmp 5f +4: and $0xfd, %al + + /* clear the INIT_NOW bit don't accidently reset the machine */ +5: and $0xfe, %al + outb %al, %dx + +6: /* use keyboard controller */ pushl %eax call gloop1 @@ -1661,9 +1683,12 @@ gloopint1: inb $K_STATUS + cmpb $0xff, %al + jz gloopint1_done andb $K_IBUF_FUL, %al jnz gloopint1 +gloopint1_done: movb $KB_OUTPUT_MASK, %al cmpb $0, 0x8(%esp) jz gdoit @@ -1684,6 +1709,8 @@ gloop1: inb $K_STATUS + cmpb $0xff, %al + jz gloop2ret andb $K_IBUF_FUL, %al jnz gloop1 @@ -1991,6 +2018,11 @@ ENTRY(console_getkey) push %ebp +wait_for_key: + call EXT_C(console_checkkey) + incl %eax + jz wait_for_key + call EXT_C(prot_to_real) .code16