mkinitrd-magellan/isolinux/graphics.inc

;; -----------------------------------------------------------------------
;;
;;   Copyright 1994-2008 H. Peter Anvin - All Rights Reserved
;;
;;   This program is free software; you can redistribute it and/or modify
;;   it under the terms of the GNU General Public License as published by
;;   the Free Software Foundation, Inc., 53 Temple Place Ste 330,
;;   Boston MA 02111-1307, USA; either version 2 of the License, or
;;   (at your option) any later version; incorporated herein by reference.
;;
;; -----------------------------------------------------------------------

; ----------------------------------------------------------------------------
;  VGA splash screen code
; ----------------------------------------------------------------------------

;
; vgadisplayfile:
;	Display a graphical splash screen.
;	The file is already opened on the top of the getc stack.
;
;	Assumes CS == DS == ES.
;
		section .text

vgadisplayfile:
		; This is a cheap and easy way to make sure the screen is
		; cleared in case we were in graphics mode already
		call vgaclearmode
		call vgasetmode
		jnz .error_nz

.graphalready:
		; Load the header.
		mov cx,4+2*2+16*3
		mov di,LSSHeader
.gethdr:
		call getc
		stosb
		loop .gethdr
		jc .error

		; The header WILL be in the first chunk.
		cmp dword [LSSMagic],0x1413f33d	; Magic number
.error_nz:	jne .error

		mov dx,GraphColorMap		; Color map offset
		mov ax,1012h			; Set RGB registers
		xor bx,bx			; First register number
		mov cx,16			; 16 registers
		int 10h

.movecursor:
		mov ax,[GraphYSize]		; Number of pixel rows
		mov dx,[VGAFontSize]
		add ax,dx
		dec ax
		div dl
		xor dx,dx			; Set column to 0
		cmp al,[VidRows]
		jb .rowsok
		mov al,[VidRows]
		dec al
.rowsok:
		mov dh,al
		mov ah,2
		xor bx,bx
		int 10h				; Set cursor below image

		mov cx,[GraphYSize]		; Number of graphics rows
		mov word [VGAPos],0

.drawpixelrow:
		push cx
		mov di,VGARowBuffer
		; Pre-clear the row buffer
		push di
		push di
		mov cx,640/4
		xor eax,eax
		rep stosd
		pop di
		mov cx,[GraphXSize]
		call rledecode			; Decode one row
		pop si
		mov di,VGAPlaneBuffer
		push di
		mov bp,640
		call packedpixel2vga
		pop si
		push es
		mov di,0A000h			; VGA segment
		mov es,di
		mov di,[VGAPos]
		call outputvga
		pop es
		add word [VGAPos],640/8
		pop cx
		loop .drawpixelrow

.error:
		jmp close			; Tailcall!

;
; rledecode:
;	Decode a pixel row in RLE16 format.
;
; getc stack	-> input
; CX		-> pixel count
; ES:DI		-> output (packed pixel)
;
rledecode:
		xor dx,dx		; DL = last pixel, DH = nybble buffer
.loop:
		call .getnybble
		cmp al,dl
		je .run			; Start of run sequence
		stosb
		mov dl,al
		dec cx
		jnz .loop
.done:
		ret
.run:
		xor bx,bx
		call .getnybble
		or bl,al
		jz .longrun
.dorun:
		push cx
		mov cx,bx
		mov al,dl
		rep stosb
		pop cx
		sub cx,bx
		ja .loop
		jmp short .done
.longrun:
		call .getnybble
		mov bl,al
		call .getnybble
		shl al,4
		or bl,al
		add bx,16
		jmp short .dorun

.getnybble:
		test dh,10h
		jz .low
		and dh,0Fh
		mov al,dh
		ret
.low:
		call getc
		mov dh,al
		shr dh,4
		or dh,10h		; Nybble already read
		and al,0Fh
		ret

;
; packedpixel2vga:
;	Convert packed-pixel to VGA bitplanes
;
; DS:SI -> packed pixel string
; BP    -> pixel count (multiple of 8)
; DS:DI -> output (four planes)
;
packedpixel2vga:
		xor cx,cx
.planeloop:
		inc cx
		push si
		push bp
.loop1:
		mov bx,8
.loop2:
		lodsb
		shr al,cl
		rcl dl,1		; VGA is bigendian.  Sigh.
		dec bx
		jnz .loop2
		mov [di],dl
		inc di
		sub bp,byte 8
		ja .loop1
		pop bp
		pop si
		cmp cl,3
		jbe .planeloop
		ret

;
; outputvga:
;	Output four subsequent lines of VGA data
;
; DS:SI	-> four planes @ 640/8=80 bytes
; ES:DI	-> pointer into VGA memory
;
outputvga:
		mov dx,3C4h	; VGA Sequencer Register select port
		mov al,2	; Sequencer mask
		out dx,al	; Select the sequencer mask
		inc dx		; VGA Sequencer Register data port
		dec ax		; AL <- 1
.loop1:
		out dx,al	; Select the bit plane to write
		push di
		mov cx,640/32
		rep movsd
		pop di
		add ax,ax
		cmp al,8
		jbe .loop1
		ret

;
; vgasetmode:
;	Enable VGA graphics, if possible; return ZF=1 on success
;	DS must be set to the base segment; ES is set to DS.
;
vgasetmode:
		push ds
		pop es
		mov al,[UsingVGA]
		cmp al,01h
		je .success		; Nothing to do...
		test al,04h
		jz .notvesa
		; We're in a VESA mode, which means VGA; use VESA call
		; to revert the mode, and then call the conventional
		; mode-setting for good measure...
		mov ax,4F02h
		mov bx,0012h
		int 10h
		jmp .setmode
.notvesa:
		mov ax,1A00h		; Get video card and monitor
		xor bx,bx
		int 10h
		sub bl, 7		; BL=07h and BL=08h OK
		cmp bl, 1
		ja .error		; ZF=0
;		mov bx,TextColorReg
;		mov dx,1009h		; Read color registers
;		int 10h
.setmode:
		mov ax,0012h		; Set mode = 640x480 VGA 16 colors
		int 10h
		mov dx,linear_color
		mov ax,1002h		; Write color registers
		int 10h
		mov [UsingVGA], byte 1

		; Set GXPixCols and GXPixRows
		mov dword [GXPixCols],640+(480 << 16)

		call use_font		; Set graphics font/data
		mov byte [ScrollAttribute], 00h

.success:
		xor ax,ax		; Set ZF
.error:
		ret

;
; vgaclearmode:
;	Disable VGA graphics.  It is not safe to assume any value
;	for DS or ES.
;
vgaclearmode:
		push ds
		push es
		pushad
		mov ax,cs
		mov ds,ax
		mov es,ax
		mov al,[UsingVGA]
		and al,al		; Already in text mode?
		jz .done
		test al,04h
		jz .notvesa
		mov ax,4F02h		; VESA return to normal video mode
		mov bx,0003h
		int 10h
.notvesa:
		mov ax,0003h		; Return to normal video mode
		int 10h
;		mov dx,TextColorReg	; Restore color registers
;		mov ax,1002h
;		int 10h
		mov [UsingVGA], byte 0

		mov byte [ScrollAttribute], 07h
		call use_font		; Restore text font/data
.done:
		popad
		pop es
		pop ds
		ret

;
; vgashowcursor/vgahidecursor:
;	If VGA graphics is enabled, draw a cursor/clear a cursor
;
vgashowcursor:
		pushad
		mov al,'_'
		jmp short vgacursorcommon
vgahidecursor:
		pushad
		mov al,' '
vgacursorcommon:
		cmp [UsingVGA], byte 1
		jne .done
		mov ah,09h
		mov bx,0007h
		mov cx,1
		int 10h
.done:
		popad
		ret


		section .data
		; Map colors to consecutive DAC registers
linear_color	db 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 0

		; See comboot.doc, INT 22h AX=0017h for the semantics
		; of this byte.
UsingVGA	db 0

		section .bss2
		alignb 4
LSSHeader	equ $
LSSMagic	resd 1			; Magic number
GraphXSize	resw 1			; Width of splash screen file
GraphYSize	resw 1			; Height of splash screen file
GraphColorMap	resb 3*16
VGAPos		resw 1			; Pointer into VGA memory
VGAFilePtr	resw 1			; Pointer into VGAFileBuf
; TextColorReg	resb 17			; VGA color registers for text mode
%if IS_SYSLINUX
VGAFileBuf	resb FILENAME_MAX+2	; Unmangled VGA image name
%else
VGAFileBuf	resb FILENAME_MAX	; Unmangled VGA image name
%endif
VGAFileBufEnd	equ $
VGAFileMBuf	resb FILENAME_MAX	; Mangled VGA image name

		alignb 4
VGARowBuffer	resb 640+80		; Decompression buffer
VGAPlaneBuffer	resb (640/8)*4		; Plane buffers
1	;; -----------------------------------------------------------------------
2	;;
3	;; Copyright 1994-2008 H. Peter Anvin - All Rights Reserved
4	;;
5	;; This program is free software; you can redistribute it and/or modify
6	;; it under the terms of the GNU General Public License as published by
7	;; the Free Software Foundation, Inc., 53 Temple Place Ste 330,
8	;; Boston MA 02111-1307, USA; either version 2 of the License, or
9	;; (at your option) any later version; incorporated herein by reference.
10	;;
11	;; -----------------------------------------------------------------------
12
13	; ----------------------------------------------------------------------------
14	; VGA splash screen code
15	; ----------------------------------------------------------------------------
16
17	;
18	; vgadisplayfile:
19	; Display a graphical splash screen.
20	; The file is already opened on the top of the getc stack.
21	;
22	; Assumes CS == DS == ES.
23	;
24	section .text
25
26	vgadisplayfile:
27	; This is a cheap and easy way to make sure the screen is
28	; cleared in case we were in graphics mode already
29	call vgaclearmode
30	call vgasetmode
31	jnz .error_nz
32
33	.graphalready:
34	; Load the header.
35	mov cx,4+22+163
36	mov di,LSSHeader
37	.gethdr:
38	call getc
39	stosb
40	loop .gethdr
41	jc .error
42
43	; The header WILL be in the first chunk.
44	cmp dword [LSSMagic],0x1413f33d ; Magic number
45	.error_nz: jne .error
46
47	mov dx,GraphColorMap ; Color map offset
48	mov ax,1012h ; Set RGB registers
49	xor bx,bx ; First register number
50	mov cx,16 ; 16 registers
51	int 10h
52
53	.movecursor:
54	mov ax,[GraphYSize] ; Number of pixel rows
55	mov dx,[VGAFontSize]
56	add ax,dx
57	dec ax
58	div dl
59	xor dx,dx ; Set column to 0
60	cmp al,[VidRows]
61	jb .rowsok
62	mov al,[VidRows]
63	dec al
64	.rowsok:
65	mov dh,al
66	mov ah,2
67	xor bx,bx
68	int 10h ; Set cursor below image
69
70	mov cx,[GraphYSize] ; Number of graphics rows
71	mov word [VGAPos],0
72
73	.drawpixelrow:
74	push cx
75	mov di,VGARowBuffer
76	; Pre-clear the row buffer
77	push di
78	push di
79	mov cx,640/4
80	xor eax,eax
81	rep stosd
82	pop di
83	mov cx,[GraphXSize]
84	call rledecode ; Decode one row
85	pop si
86	mov di,VGAPlaneBuffer
87	push di
88	mov bp,640
89	call packedpixel2vga
90	pop si
91	push es
92	mov di,0A000h ; VGA segment
93	mov es,di
94	mov di,[VGAPos]
95	call outputvga
96	pop es
97	add word [VGAPos],640/8
98	pop cx
99	loop .drawpixelrow
100
101	.error:
102	jmp close ; Tailcall!
103
104	;
105	; rledecode:
106	; Decode a pixel row in RLE16 format.
107	;
108	; getc stack -> input
109	; CX -> pixel count
110	; ES:DI -> output (packed pixel)
111	;
112	rledecode:
113	xor dx,dx ; DL = last pixel, DH = nybble buffer
114	.loop:
115	call .getnybble
116	cmp al,dl
117	je .run ; Start of run sequence
118	stosb
119	mov dl,al
120	dec cx
121	jnz .loop
122	.done:
123	ret
124	.run:
125	xor bx,bx
126	call .getnybble
127	or bl,al
128	jz .longrun
129	.dorun:
130	push cx
131	mov cx,bx
132	mov al,dl
133	rep stosb
134	pop cx
135	sub cx,bx
136	ja .loop
137	jmp short .done
138	.longrun:
139	call .getnybble
140	mov bl,al
141	call .getnybble
142	shl al,4
143	or bl,al
144	add bx,16
145	jmp short .dorun
146
147	.getnybble:
148	test dh,10h
149	jz .low
150	and dh,0Fh
151	mov al,dh
152	ret
153	.low:
154	call getc
155	mov dh,al
156	shr dh,4
157	or dh,10h ; Nybble already read
158	and al,0Fh
159	ret
160
161	;
162	; packedpixel2vga:
163	; Convert packed-pixel to VGA bitplanes
164	;
165	; DS:SI -> packed pixel string
166	; BP -> pixel count (multiple of 8)
167	; DS:DI -> output (four planes)
168	;
169	packedpixel2vga:
170	xor cx,cx
171	.planeloop:
172	inc cx
173	push si
174	push bp
175	.loop1:
176	mov bx,8
177	.loop2:
178	lodsb
179	shr al,cl
180	rcl dl,1 ; VGA is bigendian. Sigh.
181	dec bx
182	jnz .loop2
183	mov [di],dl
184	inc di
185	sub bp,byte 8
186	ja .loop1
187	pop bp
188	pop si
189	cmp cl,3
190	jbe .planeloop
191	ret
192
193	;
194	; outputvga:
195	; Output four subsequent lines of VGA data
196	;
197	; DS:SI -> four planes @ 640/8=80 bytes
198	; ES:DI -> pointer into VGA memory
199	;
200	outputvga:
201	mov dx,3C4h ; VGA Sequencer Register select port
202	mov al,2 ; Sequencer mask
203	out dx,al ; Select the sequencer mask
204	inc dx ; VGA Sequencer Register data port
205	dec ax ; AL <- 1
206	.loop1:
207	out dx,al ; Select the bit plane to write
208	push di
209	mov cx,640/32
210	rep movsd
211	pop di
212	add ax,ax
213	cmp al,8
214	jbe .loop1
215	ret
216
217	;
218	; vgasetmode:
219	; Enable VGA graphics, if possible; return ZF=1 on success
220	; DS must be set to the base segment; ES is set to DS.
221	;
222	vgasetmode:
223	push ds
224	pop es
225	mov al,[UsingVGA]
226	cmp al,01h
227	je .success ; Nothing to do...
228	test al,04h
229	jz .notvesa
230	; We're in a VESA mode, which means VGA; use VESA call
231	; to revert the mode, and then call the conventional
232	; mode-setting for good measure...
233	mov ax,4F02h
234	mov bx,0012h
235	int 10h
236	jmp .setmode
237	.notvesa:
238	mov ax,1A00h ; Get video card and monitor
239	xor bx,bx
240	int 10h
241	sub bl, 7 ; BL=07h and BL=08h OK
242	cmp bl, 1
243	ja .error ; ZF=0
244	; mov bx,TextColorReg
245	; mov dx,1009h ; Read color registers
246	; int 10h
247	.setmode:
248	mov ax,0012h ; Set mode = 640x480 VGA 16 colors
249	int 10h
250	mov dx,linear_color
251	mov ax,1002h ; Write color registers
252	int 10h
253	mov [UsingVGA], byte 1
254
255	; Set GXPixCols and GXPixRows
256	mov dword [GXPixCols],640+(480 << 16)
257
258	call use_font ; Set graphics font/data
259	mov byte [ScrollAttribute], 00h
260
261	.success:
262	xor ax,ax ; Set ZF
263	.error:
264	ret
265
266	;
267	; vgaclearmode:
268	; Disable VGA graphics. It is not safe to assume any value
269	; for DS or ES.
270	;
271	vgaclearmode:
272	push ds
273	push es
274	pushad
275	mov ax,cs
276	mov ds,ax
277	mov es,ax
278	mov al,[UsingVGA]
279	and al,al ; Already in text mode?
280	jz .done
281	test al,04h
282	jz .notvesa
283	mov ax,4F02h ; VESA return to normal video mode
284	mov bx,0003h
285	int 10h
286	.notvesa:
287	mov ax,0003h ; Return to normal video mode
288	int 10h
289	; mov dx,TextColorReg ; Restore color registers
290	; mov ax,1002h
291	; int 10h
292	mov [UsingVGA], byte 0
293
294	mov byte [ScrollAttribute], 07h
295	call use_font ; Restore text font/data
296	.done:
297	popad
298	pop es
299	pop ds
300	ret
301
302	;
303	; vgashowcursor/vgahidecursor:
304	; If VGA graphics is enabled, draw a cursor/clear a cursor
305	;
306	vgashowcursor:
307	pushad
308	mov al,'_'
309	jmp short vgacursorcommon
310	vgahidecursor:
311	pushad
312	mov al,' '
313	vgacursorcommon:
314	cmp [UsingVGA], byte 1
315	jne .done
316	mov ah,09h
317	mov bx,0007h
318	mov cx,1
319	int 10h
320	.done:
321	popad
322	ret
323
324
325	section .data
326	; Map colors to consecutive DAC registers
327	linear_color db 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 0
328
329	; See comboot.doc, INT 22h AX=0017h for the semantics
330	; of this byte.
331	UsingVGA db 0
332
333	section .bss2
334	alignb 4
335	LSSHeader equ $
336	LSSMagic resd 1 ; Magic number
337	GraphXSize resw 1 ; Width of splash screen file
338	GraphYSize resw 1 ; Height of splash screen file
339	GraphColorMap resb 3*16
340	VGAPos resw 1 ; Pointer into VGA memory
341	VGAFilePtr resw 1 ; Pointer into VGAFileBuf
342	; TextColorReg resb 17 ; VGA color registers for text mode
343	%if IS_SYSLINUX
344	VGAFileBuf resb FILENAME_MAX+2 ; Unmangled VGA image name
345	%else
346	VGAFileBuf resb FILENAME_MAX ; Unmangled VGA image name
347	%endif
348	VGAFileBufEnd equ $
349	VGAFileMBuf resb FILENAME_MAX ; Mangled VGA image name
350
351	alignb 4
352	VGARowBuffer resb 640+80 ; Decompression buffer
353	VGAPlaneBuffer resb (640/8)*4 ; Plane buffers