; vesa.inc
; Author: Josh Holtrop
; Date: 01/04/05
; Modified: 01/04/05
; real mode vesa functions

; sample bochs VBE modes:
;0x000c6a86 <bogus+       0>:    0x0100  0x0101  0x0102  0x0103  0x0105  0x0110  0x0111  0x0112
;0x000c6a96 <bogus+      16>:    0x0113  0x0114  0x0115  0x0116  0x0117  0x0118  0x0142  0x0143
;0x000c6aa6 <bogus+      32>:    0x0144  0x0146  0xffff

%define VESA_MODE_SUPPORTED	0x01
%define VESA_MODE_COLOR		0x08
%define VESA_MODE_GRAPHICS	0x10
%define VESA_MODE_LFB		0x80

vesa_return:	dw	0

vesa_get_info:			;vesa_get_info(word seg, word offset)
	push	bp
	mov	bp, sp
	pusha
	push	es
	push	ds

	mov	ax, [bp + 4]
	mov	es, ax
	mov	di, [bp + 6]
	mov	ax, 0x4F00
	int	0x10
	sub	ax, 0x004F
	mov	[vesa_return], ax

	pop	ds
	pop	es
	popa
	pop	bp
	mov	ax, [vesa_return]
	ret


vesa_get_mode_info:			;vesa_get_info(word seg, word offset, word mode)
	push	bp
	mov	bp, sp
	pusha
	push	es
	push	ds

	mov	ax, [bp + 4]
	mov	es, ax
	mov	di, [bp + 6]
	mov	cx, [bp + 8]
	mov	ax, 0x4F01
	int	0x10
	sub	ax, 0x004F
	mov	[vesa_return], ax

	pop	ds
	pop	es
	popa
	pop	bp
	mov	ax, [vesa_return]
	ret


vesa_set_mode:				;vesa_set_mode(word mode)
	push	bp
	mov	bp, sp
	pusha
	push	es
	push	ds

	mov	bx, [bp + 4]
	mov	ax, 0x4F02
	int	0x10
	sub	ax, 0x004F
	mov	[vesa_return], ax

	pop	ds
	pop	es
	popa
	pop	bp
	mov	ax, [vesa_return]
	ret