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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␊
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␊
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 * Default GTF parameter values.␊
121 */␊
122#define kCellGranularity 8.0 // character cell granularity␊
123#define kMinVSyncPlusBP 550.0 // min VSync + BP interval (us)␊
124#define kMinFrontPorch 1.0 // minimum front porch in lines(V)/cells(H)␊
125#define kVSyncLines 3.0 // width of VSync in lines␊
126#define kHSyncWidth 8.0 // HSync as a percent of total line width␊
127#define kC 30.0 // C = (C'-J) * (K/256) + J␊
128#define kM 300.0 // M = K/256 * M'␊
129␊
130int Round(double f)␊
131{␊
132␉return (int)(f + 0.5);␊
133}␊
134␊
135/*␊
136 * from http://www.azillionmonkeys.com/qed/sqroot.html␊
137 */␊
138␊
139double Sqrt( double y )␊
140{␊
141␉double x, z, tempf;␊
142␉unsigned long *tfptr = ((unsigned long *)&tempf) + 1;␊
143␉␊
144␉tempf = y;␊
145␉*tfptr = (0xbfcdd90a - *tfptr)>>1; /* estimate of 1/sqrt(y) */␊
146␉x = tempf;␊
147␉z = y*0.5; /* hoist out the “/2” */␊
148␉x = (1.5*x) - (x*x)*(x*z); /* iteration formula */␊
149␉x = (1.5*x) - (x*x)*(x*z);␊
150␉x = (1.5*x) - (x*x)*(x*z);␊
151␉x = (1.5*x) - (x*x)*(x*z);␊
152␉x = (1.5*x) - (x*x)*(x*z);␊
153␉return x*y;␊
154}␊
155␊
156int generateCRTCTiming( unsigned short width,␊
157 unsigned short height,␊
158 unsigned long paramValue, ␊
159 int paramType,␊
160 VBECRTCInfoBlock * timing )␊
161{␊
162 double h_period_est, h_freq, h_period, h_total_pixels, h_sync_pixels;␊
163 double h_active_pixels, h_ideal_duty_cycle, h_blank_pixels, pixel_freq = 0;␊
164 double v_sync_plus_bp = 0, v_total_lines = 0, v_field_rate_est, v_frame_rate = 0;␊
165 const double h_pixels = (double) width;␊
166 const double v_lines = (double) height;␊
167␊
168 enum {␊
169 left_margin_pixels = 0,␊
170 right_margin_pixels = 0,␊
171 top_margin_lines = 0,␊
172 bot_margin_lines = 0,␊
173 interlace = 0␊
174 };␊
175␊
176 // Total number of active pixels in image and both margins␊
177 h_active_pixels = h_pixels + left_margin_pixels + right_margin_pixels;␊
178␊
179 if (paramType == kCRTCParamPixelClock)␊
180 {␊
181 // Pixel clock provided in MHz␊
182 pixel_freq = (double) paramValue / 1000000;␊
183␊
184 // Ideal horizontal period from the blanking duty cycle equation␊
185 h_period = ((kC - 100) + (Sqrt(((100 - kC) * (100 - kC)) + (0.4 * kM *␊
186 (h_active_pixels + right_margin_pixels + left_margin_pixels) /␊
187 pixel_freq)))) / 2.0 / kM * 1000;␊
188 }␊
189 else /* kCRTCParamRefreshRate */␊
190 {␊
191 double v_field_rate_in = (double) paramValue;␊
192␊
193 // Estimate the horizontal period␊
194 h_period_est = ((1 / v_field_rate_in) - kMinVSyncPlusBP / 1000000) /␊
195 (v_lines + (2 * top_margin_lines) + kMinFrontPorch + interlace) * ␊
196 1000000;␊
197␊
198 // Number of lines in Vsync + back porch␊
199 v_sync_plus_bp = Round(kMinVSyncPlusBP / h_period_est);␊
200␊
201 // Total number of lines in Vetical field period␊
202 v_total_lines = v_lines + top_margin_lines + bot_margin_lines +␊
203 v_sync_plus_bp + interlace + kMinFrontPorch;␊
204␊
205 // Estimate the vertical field frequency␊
206 v_field_rate_est = 1 / h_period_est / v_total_lines * 1000000;␊
207␊
208 // Find the actual horizontal period␊
209 h_period = h_period_est / (v_field_rate_in / v_field_rate_est);␊
210␊
211 // Find the vertical frame rate (no interlace)␊
212 v_frame_rate = 1 / h_period / v_total_lines * 1000000;␊
213 }␊
214␊
215 // Ideal blanking duty cycle from the blanking duty cycle equation␊
216 h_ideal_duty_cycle = kC - (kM * h_period / 1000);␊
217␊
218 // Number of pixels in the blanking time to the nearest double character cell␊
219 h_blank_pixels = Round(h_active_pixels * h_ideal_duty_cycle /␊
220 (100 - h_ideal_duty_cycle) / (2 * kCellGranularity)) *␊
221 (2 * kCellGranularity);␊
222␊
223 // Total number of horizontal pixels␊
224 h_total_pixels = h_active_pixels + h_blank_pixels;␊
225␊
226 if (paramType == kCRTCParamPixelClock)␊
227 {␊
228 // Horizontal frequency␊
229 h_freq = pixel_freq / h_total_pixels * 1000;␊
230␊
231 // Number of lines in V sync + back porch␊
232 v_sync_plus_bp = Round(kMinVSyncPlusBP * h_freq / 1000);␊
233␊
234 // Total number of lines in vertical field period␊
235 v_total_lines = v_lines + top_margin_lines + bot_margin_lines +␊
236 interlace + v_sync_plus_bp + kMinFrontPorch;␊
237␊
238 // Vertical frame frequency␊
239 v_frame_rate = Round(h_freq / v_total_lines * 1000);␊
240 }␊
241 else␊
242 {␊
243 // Find pixel clock frequency␊
244 pixel_freq = Round(h_total_pixels / h_period);␊
245 }␊
246␊
247 h_sync_pixels = Round(h_total_pixels * kHSyncWidth / 100 / kCellGranularity) *␊
248 kCellGranularity;␊
249␊
250 timing->HTotal = h_total_pixels;␊
251 timing->HSyncStart = h_active_pixels + (h_blank_pixels / 2) - h_sync_pixels;␊
252 timing->HSyncEnd = timing->HSyncStart + h_sync_pixels;␊
253 timing->VTotal = v_total_lines;␊
254 timing->VSyncStart = v_total_lines - v_sync_plus_bp;␊
255 timing->VSyncEnd = timing->VSyncStart + kVSyncLines;␊
256 timing->Flags = kCRTCNegativeHorizontalSync;␊
257 timing->PixelClock = pixel_freq * 1000000;␊
258 timing->RefreshRate = v_frame_rate * 100;␊
259␊
260 return 0;␊
261}␊
262␊
263int setVBEMode(unsigned short mode, const VBECRTCInfoBlock * timing)␊
264{␊
265 bb.intno = 0x10;␊
266 bb.eax.rr = funcSetMode;␊
267 bb.ebx.rr = mode;␊
268 if (timing) {␊
269 bb.es = SEG(timing);␊
270 bb.edi.rr = OFF(timing);␊
271 }␊
272 bios(&bb);␊
273 return(bb.eax.r.h);␊
274}␊
275␊
276int setVBEPalette(void *palette)␊
277{␊
278 bb.intno = 0x10;␊
279 bb.eax.rr = funcGetSetPaletteData;␊
280 bb.ebx.r.l = subfuncSet;␊
281 bb.ecx.rr = 256;␊
282 bb.edx.rr = 0;␊
283 bb.es = SEG(palette);␊
284 bb.edi.rr = OFF(palette);␊
285 bios(&bb);␊
286 return(bb.eax.r.h);␊
287}␊
288␊
289int getVBEPalette(void *palette)␊
290{␊
291 bb.intno = 0x10;␊
292 bb.eax.rr = funcGetSetPaletteData;␊
293 bb.ebx.r.l = subfuncGet;␊
294 bb.ecx.rr = 256;␊
295 bb.edx.rr = 0;␊
296 bb.es = SEG(palette);␊
297 bb.edi.rr = OFF(palette);␊
298 bios(&bb);␊
299 return(bb.eax.r.h);␊
300}␊
301␊
302int getVBECurrentMode(unsigned short *mode)␊
303{␊
304 bb.intno = 0x10;␊
305 bb.eax.rr = funcGetCurrentMode;␊
306 bios(&bb);␊
307 *mode = bb.ebx.rr;␊
308 return(bb.eax.r.h);␊
309}␊
310␊
311int getVBEPixelClock(unsigned short mode, unsigned long * pixelClock)␊
312{␊
313 bb.intno = 0x10;␊
314 bb.eax.rr = funcGetSetPixelClock;␊
315 bb.ebx.r.l = 0;␊
316 bb.ecx.rx = *pixelClock;␊
317 bb.edx.rr = mode;␊
318 bios(&bb);␊
319 *pixelClock = bb.ecx.rx;␊
320 return(bb.eax.r.h);␊
321}␊
322

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