diff options
Diffstat (limited to 'c/src/lib/libbsp/i386/pc386/start/start16.S')
-rw-r--r-- | c/src/lib/libbsp/i386/pc386/start/start16.S | 25 |
1 files changed, 23 insertions, 2 deletions
diff --git a/c/src/lib/libbsp/i386/pc386/start/start16.S b/c/src/lib/libbsp/i386/pc386/start/start16.S index 4b12408cd6..92e04468de 100644 --- a/c/src/lib/libbsp/i386/pc386/start/start16.S +++ b/c/src/lib/libbsp/i386/pc386/start/start16.S @@ -115,6 +115,10 @@ _start16: outb %al, $0x60 call empty_8042 + call delay + call delay + call delay + movl %cs:HDRSTART + HDROFF, %eax # pushl %eax # jump to start of 32 bit code ret # @@ -122,13 +126,29 @@ _start16: /*----------------------------------------------------------------------------+ | delay +------------------------------------------------------------------------------ -| Delay is needed after doing I/O. We do it by writing to a non-existent port. +| Delay is needed after doing I/O. +| +| The outb version is OK on most machines BUT the loop version ... +| +| will delay for 1us on 1Gz machine, it will take a little bit +| longer on slower machines, however, it does not matter because we +| are going to call this function only a few times + +----------------------------------------------------------------------------*/ + .p2align 4 .globl _delay .globl delay delay: _delay: - outb %al, $0xED # about 1uS delay +/* + outb %al, $0xED # about 1uS delay on most machines +*/ +/* + + movl $0x200, %eax +delay1: + dec %eax + jnz delay1 ret /*----------------------------------------------------------------------------+ @@ -139,6 +159,7 @@ _delay: | No timeout is used - if this hangs there is something wrong with the machine, | and we probably couldn't proceed anyway. +----------------------------------------------------------------------------*/ + .p2align 4 .globl _empty_8042 .globl empty_8042 empty_8042: |