[Qemu-devel] Re: [Bochs-developers] [PATCH v2 1/6] Move PIC initialization out ofline to save space in post code area.

["Sebastian Herbszt" <herbszt@gmx.de>]

Gleb Natapov wrote:

> There are only a couple of bytes left in post area.
> 
> Signed-off-by: Gleb Natapov <gleb@redhat.com>
> ---
> 
> bios/rombios.c |   48 ++++++++++++++++++++++++++----------------------
> 1 files changed, 26 insertions(+), 22 deletions(-)
> 
> diff --git a/bios/rombios.c b/bios/rombios.c
> index 3366ad9..88eac04 100644
> --- a/bios/rombios.c
> +++ b/bios/rombios.c
> @@ -10256,6 +10256,31 @@ rom_scan_increment:
>   mov  ds, ax
>   ret
> 
> +post_init_pic:
> +  mov al, #0x11 ; send initialisation commands
> +  out 0x20, al
> +  out 0xa0, al
> +  mov al, #0x08
> +  out 0x21, al
> +  mov al, #0x70
> +  out 0xa1, al
> +  mov al, #0x04
> +  out 0x21, al
> +  mov al, #0x02
> +  out 0xa1, al
> +  mov al, #0x01
> +  out 0x21, al
> +  out 0xa1, al
> +  mov  al, #0xb8
> +  out  0x21, AL ;master pic: unmask IRQ 0, 1, 2, 6
> +#if BX_USE_PS2_MOUSE
> +  mov  al, #0x8f
> +#else
> +  mov  al, #0x9f
> +#endif
> +  out  0xa1, AL ;slave  pic: unmask IRQ 12, 13, 14
> +  ret
> +
> ;; the following area can be used to write dynamically generated tables
>   .align 16
> bios_table_area_start:
> @@ -10516,28 +10541,7 @@ post_default_ints:
>   SET_INT_VECTOR(0x10, #0xF000, #int10_handler)
> 
>   ;; PIC
> -  mov al, #0x11 ; send initialisation commands
> -  out 0x20, al
> -  out 0xa0, al
> -  mov al, #0x08
> -  out 0x21, al
> -  mov al, #0x70
> -  out 0xa1, al
> -  mov al, #0x04
> -  out 0x21, al
> -  mov al, #0x02
> -  out 0xa1, al
> -  mov al, #0x01
> -  out 0x21, al
> -  out 0xa1, al
> -  mov  al, #0xb8
> -  out  0x21, AL ;master pic: unmask IRQ 0, 1, 2, 6
> -#if BX_USE_PS2_MOUSE
> -  mov  al, #0x8f
> -#else
> -  mov  al, #0x9f
> -#endif
> -  out  0xa1, AL ;slave  pic: unmask IRQ 12, 13, 14
> +  call post_init_pic
> 
>   mov  cx, #0xc000  ;; init vga bios
>   mov  ax, #0xc780

Looks good. Similar patch is already in the VirtualBox tree [1].

[1] http://www.virtualbox.org/changeset/12494

- Sebastian