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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//==============================================================================␊
38␊
39static inline void outi(int port, int index, int val)␊
40{␊
41 outw (port, (val << 8) | index);␊
42}␊
43␊
44␊
45//==============================================================================␊
46static inline void outib(int port, int index, int val)␊
47{␊
48 outb (port, index);␊
49 outb (port + 1, val);␊
50}␊
51␊
52␊
53//==============================================================================␊
54␊
55static inline int ini(int port, int index)␊
56{␊
57 outb (port, index);␊
58 return inb (port + 1);␊
59}␊
60␊
61␊
62//==============================================================================␊
63␊
64static inline void rmwi(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//==============================================================================␊
72␊
73int getVBEInfo(void * infoBlock)␊
74{␊
75 bb.intno = 0x10;␊
76 bb.eax.rr = funcGetControllerInfo;␊
77 bb.es = SEG( infoBlock );␊
78 bb.edi.rr = OFF( infoBlock );␊
79 bios(&bb);␊
80␊
81 return(bb.eax.r.h);␊
82}␊
83␊
84␊
85//==============================================================================␊
86␊
87int getVBEModeInfo(int mode, void * minfo_p)␊
88{␊
89 bb.intno = 0x10;␊
90 bb.eax.rr = funcGetModeInfo;␊
91 bb.ecx.rr = mode;␊
92 bb.es = SEG(minfo_p);␊
93 bb.edi.rr = OFF(minfo_p);␊
94 bios(&bb);␊
95␊
96 return(bb.eax.r.h);␊
97}␊
98␊
99␊
100//==============================================================================␊
101␊
102int getVBEDACFormat(unsigned char *format)␊
103{␊
104 bb.intno = 0x10;␊
105 bb.eax.rr = funcGetSetPaletteFormat;␊
106 bb.ebx.r.l = subfuncGet;␊
107 bios(&bb);␊
108 *format = bb.ebx.r.h;␊
109 return(bb.eax.r.h);␊
110}␊
111␊
112␊
113//==============================================================================␊
114␊
115int setVBEDACFormat(unsigned char format)␊
116{␊
117 bb.intno = 0x10;␊
118 bb.eax.rr = funcGetSetPaletteFormat;␊
119 bb.ebx.r.l = subfuncSet;␊
120 bb.ebx.r.h = format;␊
121 bios(&bb);␊
122␊
123 return(bb.eax.r.h);␊
124}␊
125␊
126␊
127/*␊
128 * Default GTF parameter values.␊
129 */␊
130#define kCellGranularity 8.0 // character cell granularity␊
131#define kMinVSyncPlusBP 550.0 // min VSync + BP interval (us)␊
132#define kMinFrontPorch 1.0 // minimum front porch in lines(V)/cells(H)␊
133#define kVSyncLines 3.0 // width of VSync in lines␊
134#define kHSyncWidth 8.0 // HSync as a percent of total line width␊
135#define kC 30.0 // C = (C'-J) * (K/256) + J␊
136#define kM 300.0 // M = K/256 * M'␊
137␊
138int Round(double f)␊
139{␊
140␉return (int)(f + 0.5);␊
141}␊
142␊
143/*␊
144 * from http://www.azillionmonkeys.com/qed/sqroot.html␊
145 */␊
146␊
147double Sqrt( double y )␊
148{␊
149␉double x, z, tempf;␊
150␉unsigned long *tfptr = ((unsigned long *)&tempf) + 1;␊
151␉␊
152␉tempf = y;␊
153␉*tfptr = (0xbfcdd90a - *tfptr)>>1; /* estimate of 1/sqrt(y) */␊
154␉x = tempf;␊
155␉z = y*0.5; /* hoist out the “/2” */␊
156␉x = (1.5*x) - (x*x)*(x*z); /* iteration formula */␊
157␉x = (1.5*x) - (x*x)*(x*z);␊
158␉x = (1.5*x) - (x*x)*(x*z);␊
159␉x = (1.5*x) - (x*x)*(x*z);␊
160␉x = (1.5*x) - (x*x)*(x*z);␊
161␉return x*y;␊
162}␊
163␊
164int generateCRTCTiming( unsigned short width,␊
165 unsigned short height,␊
166 unsigned long paramValue, ␊
167 int paramType,␊
168 VBECRTCInfoBlock * timing )␊
169{␊
170 double h_period_est, h_freq, h_period, h_total_pixels, h_sync_pixels;␊
171 double h_active_pixels, h_ideal_duty_cycle, h_blank_pixels, pixel_freq = 0;␊
172 double v_sync_plus_bp = 0, v_total_lines = 0, v_field_rate_est, v_frame_rate = 0;␊
173 const double h_pixels = (double) width;␊
174 const double v_lines = (double) height;␊
175␊
176 enum {␊
177 left_margin_pixels = 0,␊
178 right_margin_pixels = 0,␊
179 top_margin_lines = 0,␊
180 bot_margin_lines = 0,␊
181 interlace = 0␊
182 };␊
183␊
184 // Total number of active pixels in image and both margins␊
185 h_active_pixels = h_pixels + left_margin_pixels + right_margin_pixels;␊
186␊
187 if (paramType == kCRTCParamPixelClock)␊
188 {␊
189 // Pixel clock provided in MHz␊
190 pixel_freq = (double) paramValue / 1000000;␊
191␊
192 // Ideal horizontal period from the blanking duty cycle equation␊
193 h_period = ((kC - 100) + (Sqrt(((100 - kC) * (100 - kC)) + (0.4 * kM *␊
194 (h_active_pixels + right_margin_pixels + left_margin_pixels) /␊
195 pixel_freq)))) / 2.0 / kM * 1000;␊
196 }␊
197 else /* kCRTCParamRefreshRate */␊
198 {␊
199 double v_field_rate_in = (double) paramValue;␊
200␊
201 // Estimate the horizontal period␊
202 h_period_est = ((1 / v_field_rate_in) - kMinVSyncPlusBP / 1000000) /␊
203 (v_lines + (2 * top_margin_lines) + kMinFrontPorch + interlace) * ␊
204 1000000;␊
205␊
206 // Number of lines in Vsync + back porch␊
207 v_sync_plus_bp = Round(kMinVSyncPlusBP / h_period_est);␊
208␊
209 // Total number of lines in Vetical field period␊
210 v_total_lines = v_lines + top_margin_lines + bot_margin_lines +␊
211 v_sync_plus_bp + interlace + kMinFrontPorch;␊
212␊
213 // Estimate the vertical field frequency␊
214 v_field_rate_est = 1 / h_period_est / v_total_lines * 1000000;␊
215␊
216 // Find the actual horizontal period␊
217 h_period = h_period_est / (v_field_rate_in / v_field_rate_est);␊
218␊
219 // Find the vertical frame rate (no interlace)␊
220 v_frame_rate = 1 / h_period / v_total_lines * 1000000;␊
221 }␊
222␊
223 // Ideal blanking duty cycle from the blanking duty cycle equation␊
224 h_ideal_duty_cycle = kC - (kM * h_period / 1000);␊
225␊
226 // Number of pixels in the blanking time to the nearest double character cell␊
227 h_blank_pixels = Round(h_active_pixels * h_ideal_duty_cycle /␊
228 (100 - h_ideal_duty_cycle) / (2 * kCellGranularity)) *␊
229 (2 * kCellGranularity);␊
230␊
231 // Total number of horizontal pixels␊
232 h_total_pixels = h_active_pixels + h_blank_pixels;␊
233␊
234 if (paramType == kCRTCParamPixelClock)␊
235 {␊
236 // Horizontal frequency␊
237 h_freq = pixel_freq / h_total_pixels * 1000;␊
238␊
239 // Number of lines in V sync + back porch␊
240 v_sync_plus_bp = Round(kMinVSyncPlusBP * h_freq / 1000);␊
241␊
242 // Total number of lines in vertical field period␊
243 v_total_lines = v_lines + top_margin_lines + bot_margin_lines +␊
244 interlace + v_sync_plus_bp + kMinFrontPorch;␊
245␊
246 // Vertical frame frequency␊
247 v_frame_rate = Round(h_freq / v_total_lines * 1000);␊
248 }␊
249 else␊
250 {␊
251 // Find pixel clock frequency␊
252 pixel_freq = Round(h_total_pixels / h_period);␊
253 }␊
254␊
255 h_sync_pixels = Round(h_total_pixels * kHSyncWidth / 100 / kCellGranularity) *␊
256 kCellGranularity;␊
257␊
258 timing->HTotal = h_total_pixels;␊
259 timing->HSyncStart = h_active_pixels + (h_blank_pixels / 2) - h_sync_pixels;␊
260 timing->HSyncEnd = timing->HSyncStart + h_sync_pixels;␊
261 timing->VTotal = v_total_lines;␊
262 timing->VSyncStart = v_total_lines - v_sync_plus_bp;␊
263 timing->VSyncEnd = timing->VSyncStart + kVSyncLines;␊
264 timing->Flags = kCRTCNegativeHorizontalSync;␊
265 timing->PixelClock = pixel_freq * 1000000;␊
266 timing->RefreshRate = v_frame_rate * 100;␊
267␊
268 return 0;␊
269}␊
270␊
271int setVBEMode(unsigned short mode, const VBECRTCInfoBlock * timing)␊
272{␊
273 bb.intno = 0x10;␊
274 bb.eax.rr = funcSetMode;␊
275 bb.ebx.rr = mode;␊
276 if (timing) {␊
277 bb.es = SEG(timing);␊
278 bb.edi.rr = OFF(timing);␊
279 }␊
280 bios(&bb);␊
281 return(bb.eax.r.h);␊
282}␊
283␊
284int setVBEPalette(void *palette)␊
285{␊
286 bb.intno = 0x10;␊
287 bb.eax.rr = funcGetSetPaletteData;␊
288 bb.ebx.r.l = subfuncSet;␊
289 bb.ecx.rr = 256;␊
290 bb.edx.rr = 0;␊
291 bb.es = SEG(palette);␊
292 bb.edi.rr = OFF(palette);␊
293 bios(&bb);␊
294 return(bb.eax.r.h);␊
295}␊
296␊
297int getVBEPalette(void *palette)␊
298{␊
299 bb.intno = 0x10;␊
300 bb.eax.rr = funcGetSetPaletteData;␊
301 bb.ebx.r.l = subfuncGet;␊
302 bb.ecx.rr = 256;␊
303 bb.edx.rr = 0;␊
304 bb.es = SEG(palette);␊
305 bb.edi.rr = OFF(palette);␊
306 bios(&bb);␊
307 return(bb.eax.r.h);␊
308}␊
309␊
310int getVBECurrentMode(unsigned short *mode)␊
311{␊
312 bb.intno = 0x10;␊
313 bb.eax.rr = funcGetCurrentMode;␊
314 bios(&bb);␊
315 *mode = bb.ebx.rr;␊
316 return(bb.eax.r.h);␊
317}␊
318␊
319int getVBEPixelClock(unsigned short mode, unsigned long * pixelClock)␊
320{␊
321 bb.intno = 0x10;␊
322 bb.eax.rr = funcGetSetPixelClock;␊
323 bb.ebx.r.l = 0;␊
324 bb.ecx.rx = *pixelClock;␊
325 bb.edx.rr = mode;␊
326 bios(&bb);␊
327 *pixelClock = bb.ecx.rx;␊
328 return(bb.eax.r.h);␊
329}␊
330

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