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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/*␊
33 * Globals␊
34 */␊
35static biosBuf_t bb;␊
36␊
37int getVBEInfo( void * infoBlock )␊
38{␊
39 bb.intno = 0x10;␊
40 bb.eax.rr = funcGetControllerInfo;␊
41 bb.es = SEG( infoBlock );␊
42 bb.edi.rr = OFF( infoBlock );␊
43 bios( &bb );␊
44 return(bb.eax.r.h);␊
45}␊
46␊
47int getVBEModeInfo( int mode, void * minfo_p )␊
48{␊
49 bb.intno = 0x10;␊
50 bb.eax.rr = funcGetModeInfo;␊
51 bb.ecx.rr = mode;␊
52 bb.es = SEG(minfo_p);␊
53 bb.edi.rr = OFF(minfo_p);␊
54 bios(&bb);␊
55 return(bb.eax.r.h);␊
56}␊
57#if UNUSED␊
58int getVBEDACFormat(unsigned char *format)␊
59{␊
60 bb.intno = 0x10;␊
61 bb.eax.rr = funcGetSetPaletteFormat;␊
62 bb.ebx.r.l = subfuncGet;␊
63 bios(&bb);␊
64 *format = bb.ebx.r.h;␊
65 return(bb.eax.r.h);␊
66}␊
67␊
68int setVBEDACFormat(unsigned char format)␊
69{␊
70 bb.intno = 0x10;␊
71 bb.eax.rr = funcGetSetPaletteFormat;␊
72 bb.ebx.r.l = subfuncSet;␊
73 bb.ebx.r.h = format;␊
74 bios(&bb);␊
75 return(bb.eax.r.h);␊
76}␊
77#endif␊
78␊
79int getEDID( void * edidBlock, UInt8 block)␊
80{␊
81␉bzero(&bb, sizeof(bb));␊
82 bb.intno = 0x10;␊
83 bb.eax.rr = funcGetEDID;␊
84␉bb.ebx.r.l= 0x01;␊
85␉bb.edx.rr = block;␊
86␉␊
87 bb.es = SEG( edidBlock );␊
88 bb.edi.rr = OFF( edidBlock );␊
89␉␊
90 bios( &bb );␊
91 return(bb.eax.r.h);␊
92}␊
93␊
94␊
95␊
96/*␊
97 * Default GTF parameter values.␊
98 */␊
99#define kCellGranularity 8.0 // character cell granularity␊
100#define kMinVSyncPlusBP 550.0 // min VSync + BP interval (us)␊
101#define kMinFrontPorch 1.0 // minimum front porch in lines(V)/cells(H)␊
102#define kVSyncLines 3.0 // width of VSync in lines␊
103#define kHSyncWidth 8.0 // HSync as a percent of total line width␊
104#define kC 30.0 // C = (C'-J) * (K/256) + J␊
105#define kM 300.0 // M = K/256 * M'␊
106␊
107int Round(double f)␊
108{␊
109␉return (int)(f + 0.5);␊
110}␊
111␊
112/*␊
113 * from http://www.azillionmonkeys.com/qed/sqroot.html␊
114 */␊
115#if UNUSED␊
116double Sqrt( double y )␊
117{␊
118␉double x, z, tempf;␊
119␉unsigned long *tfptr = ((unsigned long *)&tempf) + 1;␊
120␉␊
121␉tempf = y;␊
122␉*tfptr = (0xbfcdd90a - *tfptr)>>1; /* estimate of 1/sqrt(y) */␊
123␉x = tempf;␊
124␉z = y*0.5; /* hoist out the “/2” */␊
125␉x = (1.5*x) - (x*x)*(x*z); /* iteration formula */␊
126␉x = (1.5*x) - (x*x)*(x*z);␊
127␉x = (1.5*x) - (x*x)*(x*z);␊
128␉x = (1.5*x) - (x*x)*(x*z);␊
129␉x = (1.5*x) - (x*x)*(x*z);␊
130␉return x*y;␊
131}␊
132␊
133int generateCRTCTiming( unsigned short width,␊
134 unsigned short height,␊
135 unsigned long paramValue, ␊
136 int paramType,␊
137 VBECRTCInfoBlock * timing )␊
138{␊
139 double h_period_est, h_freq, h_period, h_total_pixels, h_sync_pixels;␊
140 double h_active_pixels, h_ideal_duty_cycle, h_blank_pixels, pixel_freq = 0;␊
141 double v_sync_plus_bp = 0, v_total_lines = 0, v_field_rate_est, v_frame_rate = 0;␊
142 const double h_pixels = (double) width;␊
143 const double v_lines = (double) height;␊
144␊
145 enum {␊
146 left_margin_pixels = 0,␊
147 right_margin_pixels = 0,␊
148 top_margin_lines = 0,␊
149 bot_margin_lines = 0,␊
150 interlace = 0␊
151 };␊
152␊
153 // Total number of active pixels in image and both margins␊
154 h_active_pixels = h_pixels + left_margin_pixels + right_margin_pixels;␊
155␊
156 if (paramType == kCRTCParamPixelClock)␊
157 {␊
158 // Pixel clock provided in MHz␊
159 pixel_freq = (double) paramValue / 1000000;␊
160␊
161 // Ideal horizontal period from the blanking duty cycle equation␊
162 h_period = ((kC - 100) + (Sqrt(((100 - kC) * (100 - kC)) + (0.4 * kM *␊
163 (h_active_pixels + right_margin_pixels + left_margin_pixels) /␊
164 pixel_freq)))) / 2.0 / kM * 1000;␊
165 }␊
166 else /* kCRTCParamRefreshRate */␊
167 {␊
168 double v_field_rate_in = (double) paramValue;␊
169␊
170 // Estimate the horizontal period␊
171 h_period_est = ((1 / v_field_rate_in) - kMinVSyncPlusBP / 1000000) /␊
172 (v_lines + (2 * top_margin_lines) + kMinFrontPorch + interlace) * ␊
173 1000000;␊
174␊
175 // Number of lines in Vsync + back porch␊
176 v_sync_plus_bp = Round(kMinVSyncPlusBP / h_period_est);␊
177␊
178 // Total number of lines in Vetical field period␊
179 v_total_lines = v_lines + top_margin_lines + bot_margin_lines +␊
180 v_sync_plus_bp + interlace + kMinFrontPorch;␊
181␊
182 // Estimate the vertical field frequency␊
183 v_field_rate_est = 1 / h_period_est / v_total_lines * 1000000;␊
184␊
185 // Find the actual horizontal period␊
186 h_period = h_period_est / (v_field_rate_in / v_field_rate_est);␊
187␊
188 // Find the vertical frame rate (no interlace)␊
189 v_frame_rate = 1 / h_period / v_total_lines * 1000000;␊
190 }␊
191␊
192 // Ideal blanking duty cycle from the blanking duty cycle equation␊
193 h_ideal_duty_cycle = kC - (kM * h_period / 1000);␊
194␊
195 // Number of pixels in the blanking time to the nearest double character cell␊
196 h_blank_pixels = Round(h_active_pixels * h_ideal_duty_cycle /␊
197 (100 - h_ideal_duty_cycle) / (2 * kCellGranularity)) *␊
198 (2 * kCellGranularity);␊
199␊
200 // Total number of horizontal pixels␊
201 h_total_pixels = h_active_pixels + h_blank_pixels;␊
202␊
203 if (paramType == kCRTCParamPixelClock)␊
204 {␊
205 // Horizontal frequency␊
206 h_freq = pixel_freq / h_total_pixels * 1000;␊
207␊
208 // Number of lines in V sync + back porch␊
209 v_sync_plus_bp = Round(kMinVSyncPlusBP * h_freq / 1000);␊
210␊
211 // Total number of lines in vertical field period␊
212 v_total_lines = v_lines + top_margin_lines + bot_margin_lines +␊
213 interlace + v_sync_plus_bp + kMinFrontPorch;␊
214␊
215 // Vertical frame frequency␊
216 v_frame_rate = Round(h_freq / v_total_lines * 1000);␊
217 }␊
218 else␊
219 {␊
220 // Find pixel clock frequency␊
221 pixel_freq = Round(h_total_pixels / h_period);␊
222 }␊
223␊
224 h_sync_pixels = Round(h_total_pixels * kHSyncWidth / 100 / kCellGranularity) *␊
225 kCellGranularity;␊
226␊
227 timing->HTotal = h_total_pixels;␊
228 timing->HSyncStart = h_active_pixels + (h_blank_pixels / 2) - h_sync_pixels;␊
229 timing->HSyncEnd = timing->HSyncStart + h_sync_pixels;␊
230 timing->VTotal = v_total_lines;␊
231 timing->VSyncStart = v_total_lines - v_sync_plus_bp;␊
232 timing->VSyncEnd = timing->VSyncStart + kVSyncLines;␊
233 timing->Flags = kCRTCNegativeHorizontalSync;␊
234 timing->PixelClock = pixel_freq * 1000000;␊
235 timing->RefreshRate = v_frame_rate * 100;␊
236␊
237 return 0;␊
238}␊
239␊
240#endif ␊
241␊
242int setVBEMode(unsigned short mode, const VBECRTCInfoBlock * timing)␊
243{␊
244 bb.intno = 0x10;␊
245 bb.eax.rr = funcSetMode;␊
246 bb.ebx.rr = mode;␊
247 if (timing) {␊
248 bb.es = SEG(timing);␊
249 bb.edi.rr = OFF(timing);␊
250 }␊
251 bios(&bb);␊
252 return(bb.eax.r.h);␊
253}␊
254␊
255␊
256int setVBEPalette(void *palette)␊
257{␊
258 bb.intno = 0x10;␊
259 bb.eax.rr = funcGetSetPaletteData;␊
260 bb.ebx.r.l = subfuncSet;␊
261 bb.ecx.rr = 256;␊
262 bb.edx.rr = 0;␊
263 bb.es = SEG(palette);␊
264 bb.edi.rr = OFF(palette);␊
265 bios(&bb);␊
266 return(bb.eax.r.h);␊
267}␊
268␊
269#if UNUSED␊
270␊
271int getVBEPalette(void *palette)␊
272{␊
273 bb.intno = 0x10;␊
274 bb.eax.rr = funcGetSetPaletteData;␊
275 bb.ebx.r.l = subfuncGet;␊
276 bb.ecx.rr = 256;␊
277 bb.edx.rr = 0;␊
278 bb.es = SEG(palette);␊
279 bb.edi.rr = OFF(palette);␊
280 bios(&bb);␊
281 return(bb.eax.r.h);␊
282}␊
283␊
284int getVBECurrentMode(unsigned short *mode)␊
285{␊
286 bb.intno = 0x10;␊
287 bb.eax.rr = funcGetCurrentMode;␊
288 bios(&bb);␊
289 *mode = bb.ebx.rr;␊
290 return(bb.eax.r.h);␊
291}␊
292␊
293int getVBEPixelClock(unsigned short mode, unsigned long * pixelClock)␊
294{␊
295 bb.intno = 0x10;␊
296 bb.eax.rr = funcGetSetPixelClock;␊
297 bb.ebx.r.l = 0;␊
298 bb.ecx.rx = *pixelClock;␊
299 bb.edx.rr = mode;␊
300 bios(&bb);␊
301 *pixelClock = bb.ecx.rx;␊
302 return(bb.eax.r.h);␊
303}␊
304#endif␊
305

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