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1/*␊
2 * Copyright (c) 1999-2003 Apple Computer, Inc. All rights reserved.␊
3 *␊
4 * @APPLE_LICENSE_HEADER_START@␊
5 * ␊
6 * Portions Copyright (c) 1999-2003 Apple Computer, Inc. All Rights␊
7 * Reserved. This file contains Original Code and/or Modifications of␊
8 * Original Code as defined in and that are subject to the Apple Public␊
9 * Source License Version 2.0 (the "License"). You may not use this file␊
10 * except in compliance with the License. Please obtain a copy of the␊
11 * License at http://www.apple.com/publicsource and read it before using␊
12 * this file.␊
13 * ␊
14 * The Original Code and all software distributed under the License are␊
15 * distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY KIND, EITHER␊
16 * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,␊
17 * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,␊
18 * FITNESS FOR A PARTICULAR PURPOSE OR NON- INFRINGEMENT. Please see the␊
19 * License for the specific language governing rights and limitations␊
20 * under the License.␊
21 * ␊
22 * @APPLE_LICENSE_HEADER_END@␊
23 */␊
24/*␊
25 * Copyright 1993 NeXT, Inc.␊
26 * All rights reserved.␊
27 */␊
28␊
29#include "libsaio.h"␊
30#include "vbe.h"␊
31␊
32// Various inline routines for video I/O␊
33␊
34static biosBuf_t bb;␊
35␊
36//==============================================================================␊
37#if UNUSED␊
38static inline void␊
39outi (int port, int index, int val)␊
40{␊
41 outw (port, (val << 8) | index);␊
42}␊
43␊
44//==============================================================================␊
45static inline void␊
46outib (int port, int index, int val)␊
47{␊
48 outb (port, index);␊
49 outb (port + 1, val);␊
50}␊
51␊
52//==============================================================================␊
53␊
54static inline int␊
55ini (int port, int index)␊
56{␊
57 outb (port, index);␊
58 return inb (port + 1);␊
59}␊
60␊
61//==============================================================================␊
62␊
63static inline void␊
64rmwi(int port, int index, int clear, int set)␊
65{␊
66 outb (port, index);␊
67 outb (port + 1, (inb (port + 1) & ~clear) | set);␊
68}␊
69#endif /* UNUSED */␊
70//==============================================================================␊
71␊
72int getVBEInfo( void *infoBlock )␊
73{␊
74 bb.intno = 0x10;␊
75 bb.eax.rr = funcGetControllerInfo;␊
76 bb.es = SEG( infoBlock );␊
77 bb.edi.rr = OFF( infoBlock );␊
78 bios( &bb );␊
79 return(bb.eax.r.h);␊
80}␊
81␊
82//==============================================================================␊
83␊
84int getVBEModeInfo( int mode, void *minfo_p )␊
85{␊
86 bb.intno = 0x10;␊
87 bb.eax.rr = funcGetModeInfo;␊
88 bb.ecx.rr = mode;␊
89 bb.es = SEG(minfo_p);␊
90 bb.edi.rr = OFF(minfo_p);␊
91 bios(&bb);␊
92 return(bb.eax.r.h);␊
93}␊
94␊
95//==============================================================================␊
96␊
97int getVBEDACFormat(unsigned char *format)␊
98{␊
99 bb.intno = 0x10;␊
100 bb.eax.rr = funcGetSetPaletteFormat;␊
101 bb.ebx.r.l = subfuncGet;␊
102 bios(&bb);␊
103 *format = bb.ebx.r.h;␊
104 return(bb.eax.r.h);␊
105}␊
106␊
107//==============================================================================␊
108␊
109int setVBEDACFormat(unsigned char format)␊
110{␊
111 bb.intno = 0x10;␊
112 bb.eax.rr = funcGetSetPaletteFormat;␊
113 bb.ebx.r.l = subfuncSet;␊
114 bb.ebx.r.h = format;␊
115 bios(&bb);␊
116 return(bb.eax.r.h);␊
117}␊
118␊
119//==============================================================================␊
120␊
121/*␊
122 * Default GTF parameter values.␊
123 */␊
124#define kCellGranularity 8.0 // character cell granularity␊
125#define kMinVSyncPlusBP 550.0 // min VSync + BP interval (us)␊
126#define kMinFrontPorch 1.0 // minimum front porch in lines(V)/cells(H)␊
127#define kVSyncLines 3.0 // width of VSync in lines␊
128#define kHSyncWidth 8.0 // HSync as a percent of total line width␊
129#define kC 30.0 // C = (C'-J) * (K/256) + J␊
130#define kM 300.0 // M = K/256 * M'␊
131␊
132static int Round(double f)␊
133{␊
134␉return (int)(f + 0.5);␊
135}␊
136␊
137/*␊
138 * from http://www.azillionmonkeys.com/qed/sqroot.html␊
139 */␊
140␊
141double Sqrt( double y )␊
142{␊
143␉double x, z, tempf;␊
144␉unsigned long *tfptr = ((unsigned long *)&tempf) + 1;␊
145␉␊
146␉tempf = y;␊
147␉*tfptr = (0xbfcdd90a - *tfptr)>>1; /* estimate of 1/sqrt(y) */␊
148␉x = tempf;␊
149␉z = y*0.5; /* hoist out the “/2” */␊
150␉x = (1.5*x) - (x*x)*(x*z); /* iteration formula */␊
151␉x = (1.5*x) - (x*x)*(x*z);␊
152␉x = (1.5*x) - (x*x)*(x*z);␊
153␉x = (1.5*x) - (x*x)*(x*z);␊
154␉x = (1.5*x) - (x*x)*(x*z);␊
155␉return x*y;␊
156}␊
157␊
158//==============================================================================␊
159␊
160int generateCRTCTiming( unsigned short width,␊
161 unsigned short height,␊
162 unsigned long paramValue, ␊
163 int paramType,␊
164 VBECRTCInfoBlock * timing )␊
165{␊
166 double h_period, h_total_pixels, h_sync_pixels;␊
167 double h_active_pixels, h_ideal_duty_cycle, h_blank_pixels, pixel_freq = 0;␊
168 double v_sync_plus_bp = 0, v_total_lines = 0, v_frame_rate = 0;␊
169 const double h_pixels = (double) width;␊
170 const double v_lines = (double) height;␊
171␊
172 enum {␊
173 left_margin_pixels = 0,␊
174 right_margin_pixels = 0,␊
175 top_margin_lines = 0,␊
176 bot_margin_lines = 0,␊
177 interlace = 0␊
178 };␊
179␊
180 // Total number of active pixels in image and both margins␊
181 h_active_pixels = h_pixels + left_margin_pixels + right_margin_pixels;␊
182␊
183 if (paramType == kCRTCParamPixelClock)␊
184 {␊
185 // Pixel clock provided in MHz␊
186 pixel_freq = (double) paramValue / 1000000;␊
187␊
188 // Ideal horizontal period from the blanking duty cycle equation␊
189 h_period = ((kC - 100) + (Sqrt(((100 - kC) * (100 - kC)) + (0.4 * kM *␊
190 (h_active_pixels + right_margin_pixels + left_margin_pixels) /␊
191 pixel_freq)))) / 2.0 / kM * 1000;␊
192 }␊
193 else /* kCRTCParamRefreshRate */␊
194 {␊
195 double v_field_rate_in = (double) paramValue;␊
196␊
197 // Estimate the horizontal period␊
198 double h_period_est = ((1 / v_field_rate_in) - kMinVSyncPlusBP / 1000000) /␊
199 (v_lines + (2 * top_margin_lines) + kMinFrontPorch + interlace) * ␊
200 1000000;␊
201␊
202 // Estimate the vertical field frequency␊
203 double v_field_rate_est = 1 / h_period_est / v_total_lines * 1000000;␊
204␊
205 // Number of lines in Vsync + back porch␊
206 v_sync_plus_bp = Round(kMinVSyncPlusBP / h_period_est);␊
207␊
208 // Total number of lines in Vetical field period␊
209 v_total_lines = v_lines + top_margin_lines + bot_margin_lines +␊
210 v_sync_plus_bp + interlace + kMinFrontPorch;␊
211␊
212 // Find the actual horizontal period␊
213 h_period = h_period_est / (v_field_rate_in / v_field_rate_est);␊
214␊
215 // Find the vertical frame rate (no interlace)␊
216 v_frame_rate = 1 / h_period / v_total_lines * 1000000;␊
217 }␊
218␊
219 // Ideal blanking duty cycle from the blanking duty cycle equation␊
220 h_ideal_duty_cycle = kC - (kM * h_period / 1000);␊
221␊
222 // Number of pixels in the blanking time to the nearest double character cell␊
223 h_blank_pixels = Round(h_active_pixels * h_ideal_duty_cycle /␊
224 (100 - h_ideal_duty_cycle) / (2 * kCellGranularity)) *␊
225 (2 * kCellGranularity);␊
226␊
227 // Total number of horizontal pixels␊
228 h_total_pixels = h_active_pixels + h_blank_pixels;␊
229␊
230 if (paramType == kCRTCParamPixelClock)␊
231 {␊
232 // Horizontal frequency␊
233 double h_freq = pixel_freq / h_total_pixels * 1000;␊
234␊
235 // Number of lines in V sync + back porch␊
236 v_sync_plus_bp = Round(kMinVSyncPlusBP * h_freq / 1000);␊
237␊
238 // Total number of lines in vertical field period␊
239 v_total_lines = v_lines + top_margin_lines + bot_margin_lines +␊
240 interlace + v_sync_plus_bp + kMinFrontPorch;␊
241␊
242 // Vertical frame frequency␊
243 v_frame_rate = Round(h_freq / v_total_lines * 1000);␊
244 }␊
245 else␊
246 {␊
247 // Find pixel clock frequency␊
248 pixel_freq = Round(h_total_pixels / h_period);␊
249 }␊
250␊
251 h_sync_pixels = Round(h_total_pixels * kHSyncWidth / 100 / kCellGranularity) *␊
252 kCellGranularity;␊
253␊
254 timing->HTotal = h_total_pixels;␊
255 timing->HSyncStart = h_active_pixels + (h_blank_pixels / 2) - h_sync_pixels;␊
256 timing->HSyncEnd = timing->HSyncStart + h_sync_pixels;␊
257 timing->VTotal = v_total_lines;␊
258 timing->VSyncStart = v_total_lines - v_sync_plus_bp;␊
259 timing->VSyncEnd = timing->VSyncStart + kVSyncLines;␊
260 timing->Flags = kCRTCNegativeHorizontalSync;␊
261 timing->PixelClock = pixel_freq * 1000000;␊
262 timing->RefreshRate = v_frame_rate * 100;␊
263␊
264 return 0;␊
265}␊
266␊
267//==============================================================================␊
268␊
269int setVBEMode(unsigned short mode, const VBECRTCInfoBlock * timing)␊
270{␊
271␉bb.intno = 0x10;␊
272␉bb.eax.rr = funcSetMode;␊
273␉bb.ebx.rr = mode;␊
274␉if (timing)␊
275␉{␊
276␉␉bb.es = SEG(timing);␊
277␉␉bb.edi.rr = OFF(timing);␊
278␉}␊
279␉bios(&bb);␊
280␉return(bb.eax.r.h);␊
281}␊
282␊
283//==============================================================================␊
284␊
285int setVBEPalette(void *palette)␊
286{␊
287␉bb.intno = 0x10;␊
288␉bb.eax.rr = funcGetSetPaletteData;␊
289␉bb.ebx.r.l = subfuncSet;␊
290␉bb.ecx.rr = 256;␊
291␉bb.edx.rr = 0;␊
292␉bb.es = SEG(palette);␊
293␉bb.edi.rr = OFF(palette);␊
294␉bios(&bb);␊
295␉return(bb.eax.r.h);␊
296}␊
297␊
298//==============================================================================␊
299␊
300int getVBEPalette(void *palette)␊
301{␊
302␉bb.intno = 0x10;␊
303␉bb.eax.rr = funcGetSetPaletteData;␊
304␉bb.ebx.r.l = subfuncGet;␊
305␉bb.ecx.rr = 256;␊
306␉bb.edx.rr = 0;␊
307␉bb.es = SEG(palette);␊
308␉bb.edi.rr = OFF(palette);␊
309␉bios(&bb);␊
310␉return(bb.eax.r.h);␊
311}␊
312␊
313//==============================================================================␊
314␊
315int getVBECurrentMode(unsigned short *mode)␊
316{␊
317␉bb.intno = 0x10;␊
318␉bb.eax.rr = funcGetCurrentMode;␊
319␉bios(&bb);␊
320␉*mode = bb.ebx.rr;␊
321␉return(bb.eax.r.h);␊
322}␊
323␊
324//==============================================================================␊
325␊
326int getVBEPixelClock(unsigned short mode, unsigned long * pixelClock)␊
327{␊
328␉bb.intno = 0x10;␊
329␉bb.eax.rr = funcGetSetPixelClock;␊
330␉bb.ebx.r.l = 0;␊
331␉bb.ecx.rx = *pixelClock;␊
332␉bb.edx.rr = mode;␊
333␉bios(&bb);␊
334␉*pixelClock = bb.ecx.rx;␊
335␉return(bb.eax.r.h);␊
336}␊
337

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