xref: /linux/drivers/video/fbdev/matrox/g450_pll.c (revision 8e07e0e3964ca4e23ce7b68e2096fe660a888942)
1 /*
2  *
3  * Hardware accelerated Matrox PCI cards - G450/G550 PLL control.
4  *
5  * (c) 2001-2002 Petr Vandrovec <vandrove@vc.cvut.cz>
6  *
7  * Portions Copyright (c) 2001 Matrox Graphics Inc.
8  *
9  * Version: 1.64 2002/06/10
10  *
11  * This file is subject to the terms and conditions of the GNU General Public
12  * License. See the file COPYING in the main directory of this archive for
13  * more details.
14  *
15  */
16 
17 #include "g450_pll.h"
18 #include "matroxfb_DAC1064.h"
19 
20 static inline unsigned int g450_vco2f(unsigned char p, unsigned int fvco) {
21 	return (p & 0x40) ? fvco : fvco >> ((p & 3) + 1);
22 }
23 
24 static inline unsigned int g450_f2vco(unsigned char p, unsigned int fin) {
25 	return (p & 0x40) ? fin : fin << ((p & 3) + 1);
26 }
27 
28 static unsigned int g450_mnp2vco(const struct matrox_fb_info *minfo,
29 				 unsigned int mnp)
30 {
31 	unsigned int m, n;
32 
33 	m = ((mnp >> 16) & 0x0FF) + 1;
34 	n = ((mnp >>  7) & 0x1FE) + 4;
35 	return (minfo->features.pll.ref_freq * n + (m >> 1)) / m;
36 }
37 
38 unsigned int g450_mnp2f(const struct matrox_fb_info *minfo, unsigned int mnp)
39 {
40 	return g450_vco2f(mnp, g450_mnp2vco(minfo, mnp));
41 }
42 
43 static inline unsigned int pll_freq_delta(unsigned int f1, unsigned int f2) {
44 	if (f2 < f1) {
45     		f2 = f1 - f2;
46 	} else {
47 		f2 = f2 - f1;
48 	}
49 	return f2;
50 }
51 
52 #define NO_MORE_MNP	0x01FFFFFF
53 #define G450_MNP_FREQBITS	(0xFFFFFF43)	/* do not mask high byte so we'll catch NO_MORE_MNP */
54 
55 static unsigned int g450_nextpll(const struct matrox_fb_info *minfo,
56 				 const struct matrox_pll_limits *pi,
57 				 unsigned int *fvco, unsigned int mnp)
58 {
59 	unsigned int m, n, p;
60 	unsigned int tvco = *fvco;
61 
62 	m = (mnp >> 16) & 0xFF;
63 	p = mnp & 0xFF;
64 
65 	do {
66 		if (m == 0 || m == 0xFF) {
67 			if (m == 0) {
68 				if (p & 0x40) {
69 					return NO_MORE_MNP;
70 				}
71 			        if (p & 3) {
72 					p--;
73 				} else {
74 					p = 0x40;
75 				}
76 				tvco >>= 1;
77 				if (tvco < pi->vcomin) {
78 					return NO_MORE_MNP;
79 				}
80 				*fvco = tvco;
81 			}
82 
83 			p &= 0x43;
84 			if (tvco < 550000) {
85 /*				p |= 0x00; */
86 			} else if (tvco < 700000) {
87 				p |= 0x08;
88 			} else if (tvco < 1000000) {
89 				p |= 0x10;
90 			} else if (tvco < 1150000) {
91 				p |= 0x18;
92 			} else {
93 				p |= 0x20;
94 			}
95 			m = 9;
96 		} else {
97 			m--;
98 		}
99 		n = ((tvco * (m+1) + minfo->features.pll.ref_freq) / (minfo->features.pll.ref_freq * 2)) - 2;
100 	} while (n < 0x03 || n > 0x7A);
101 	return (m << 16) | (n << 8) | p;
102 }
103 
104 static unsigned int g450_firstpll(const struct matrox_fb_info *minfo,
105 				  const struct matrox_pll_limits *pi,
106 				  unsigned int *vco, unsigned int fout)
107 {
108 	unsigned int p;
109 	unsigned int vcomax;
110 
111 	vcomax = pi->vcomax;
112 	if (fout > (vcomax / 2)) {
113 		if (fout > vcomax) {
114 			*vco = vcomax;
115 		} else {
116 			*vco = fout;
117 		}
118 		p = 0x40;
119 	} else {
120 		unsigned int tvco;
121 
122 		p = 3;
123 		tvco = g450_f2vco(p, fout);
124 		while (p && (tvco > vcomax)) {
125 			p--;
126 			tvco >>= 1;
127 		}
128 		if (tvco < pi->vcomin) {
129 			tvco = pi->vcomin;
130 		}
131 		*vco = tvco;
132 	}
133 	return g450_nextpll(minfo, pi, vco, 0xFF0000 | p);
134 }
135 
136 static inline unsigned int g450_setpll(const struct matrox_fb_info *minfo,
137 				       unsigned int mnp, unsigned int pll)
138 {
139 	switch (pll) {
140 		case M_PIXEL_PLL_A:
141 			matroxfb_DAC_out(minfo, M1064_XPIXPLLAM, mnp >> 16);
142 			matroxfb_DAC_out(minfo, M1064_XPIXPLLAN, mnp >> 8);
143 			matroxfb_DAC_out(minfo, M1064_XPIXPLLAP, mnp);
144 			return M1064_XPIXPLLSTAT;
145 
146 		case M_PIXEL_PLL_B:
147 			matroxfb_DAC_out(minfo, M1064_XPIXPLLBM, mnp >> 16);
148 			matroxfb_DAC_out(minfo, M1064_XPIXPLLBN, mnp >> 8);
149 			matroxfb_DAC_out(minfo, M1064_XPIXPLLBP, mnp);
150 			return M1064_XPIXPLLSTAT;
151 
152 		case M_PIXEL_PLL_C:
153 			matroxfb_DAC_out(minfo, M1064_XPIXPLLCM, mnp >> 16);
154 			matroxfb_DAC_out(minfo, M1064_XPIXPLLCN, mnp >> 8);
155 			matroxfb_DAC_out(minfo, M1064_XPIXPLLCP, mnp);
156 			return M1064_XPIXPLLSTAT;
157 
158 		case M_SYSTEM_PLL:
159 			matroxfb_DAC_out(minfo, DAC1064_XSYSPLLM, mnp >> 16);
160 			matroxfb_DAC_out(minfo, DAC1064_XSYSPLLN, mnp >> 8);
161 			matroxfb_DAC_out(minfo, DAC1064_XSYSPLLP, mnp);
162 			return DAC1064_XSYSPLLSTAT;
163 
164 		case M_VIDEO_PLL:
165 			matroxfb_DAC_out(minfo, M1064_XVIDPLLM, mnp >> 16);
166 			matroxfb_DAC_out(minfo, M1064_XVIDPLLN, mnp >> 8);
167 			matroxfb_DAC_out(minfo, M1064_XVIDPLLP, mnp);
168 			return M1064_XVIDPLLSTAT;
169 	}
170 	return 0;
171 }
172 
173 static inline unsigned int g450_cmppll(const struct matrox_fb_info *minfo,
174 				       unsigned int mnp, unsigned int pll)
175 {
176 	unsigned char m = mnp >> 16;
177 	unsigned char n = mnp >> 8;
178 	unsigned char p = mnp;
179 
180 	switch (pll) {
181 		case M_PIXEL_PLL_A:
182 			return (matroxfb_DAC_in(minfo, M1064_XPIXPLLAM) != m ||
183 				matroxfb_DAC_in(minfo, M1064_XPIXPLLAN) != n ||
184 				matroxfb_DAC_in(minfo, M1064_XPIXPLLAP) != p);
185 
186 		case M_PIXEL_PLL_B:
187 			return (matroxfb_DAC_in(minfo, M1064_XPIXPLLBM) != m ||
188 				matroxfb_DAC_in(minfo, M1064_XPIXPLLBN) != n ||
189 				matroxfb_DAC_in(minfo, M1064_XPIXPLLBP) != p);
190 
191 		case M_PIXEL_PLL_C:
192 			return (matroxfb_DAC_in(minfo, M1064_XPIXPLLCM) != m ||
193 				matroxfb_DAC_in(minfo, M1064_XPIXPLLCN) != n ||
194 				matroxfb_DAC_in(minfo, M1064_XPIXPLLCP) != p);
195 
196 		case M_SYSTEM_PLL:
197 			return (matroxfb_DAC_in(minfo, DAC1064_XSYSPLLM) != m ||
198 				matroxfb_DAC_in(minfo, DAC1064_XSYSPLLN) != n ||
199 				matroxfb_DAC_in(minfo, DAC1064_XSYSPLLP) != p);
200 
201 		case M_VIDEO_PLL:
202 			return (matroxfb_DAC_in(minfo, M1064_XVIDPLLM) != m ||
203 				matroxfb_DAC_in(minfo, M1064_XVIDPLLN) != n ||
204 				matroxfb_DAC_in(minfo, M1064_XVIDPLLP) != p);
205 	}
206 	return 1;
207 }
208 
209 static inline int g450_isplllocked(const struct matrox_fb_info *minfo,
210 				   unsigned int regidx)
211 {
212 	unsigned int j;
213 
214 	for (j = 0; j < 1000; j++) {
215 		if (matroxfb_DAC_in(minfo, regidx) & 0x40) {
216 			unsigned int r = 0;
217 			int i;
218 
219 			for (i = 0; i < 100; i++) {
220 				r += matroxfb_DAC_in(minfo, regidx) & 0x40;
221 			}
222 			return r >= (90 * 0x40);
223 		}
224 		/* udelay(1)... but DAC_in is much slower... */
225 	}
226 	return 0;
227 }
228 
229 static int g450_testpll(const struct matrox_fb_info *minfo, unsigned int mnp,
230 			unsigned int pll)
231 {
232 	return g450_isplllocked(minfo, g450_setpll(minfo, mnp, pll));
233 }
234 
235 static void updatehwstate_clk(struct matrox_hw_state* hw, unsigned int mnp, unsigned int pll) {
236 	switch (pll) {
237 		case M_SYSTEM_PLL:
238 			hw->DACclk[3] = mnp >> 16;
239 			hw->DACclk[4] = mnp >> 8;
240 			hw->DACclk[5] = mnp;
241 			break;
242 	}
243 }
244 
245 void matroxfb_g450_setpll_cond(struct matrox_fb_info *minfo, unsigned int mnp,
246 			       unsigned int pll)
247 {
248 	if (g450_cmppll(minfo, mnp, pll)) {
249 		g450_setpll(minfo, mnp, pll);
250 	}
251 }
252 
253 static inline unsigned int g450_findworkingpll(struct matrox_fb_info *minfo,
254 					       unsigned int pll,
255 					       unsigned int *mnparray,
256 					       unsigned int mnpcount)
257 {
258 	unsigned int found = 0;
259 	unsigned int idx;
260 	unsigned int mnpfound = mnparray[0];
261 
262 	for (idx = 0; idx < mnpcount; idx++) {
263 		unsigned int sarray[3];
264 		unsigned int *sptr;
265 		{
266 			unsigned int mnp;
267 
268 			sptr = sarray;
269 			mnp = mnparray[idx];
270 			if (mnp & 0x38) {
271 				*sptr++ = mnp - 8;
272 			}
273 			if ((mnp & 0x38) != 0x38) {
274 				*sptr++ = mnp + 8;
275 			}
276 			*sptr = mnp;
277 		}
278 		while (sptr >= sarray) {
279 			unsigned int mnp = *sptr--;
280 
281 			if (g450_testpll(minfo, mnp - 0x0300, pll) &&
282 			    g450_testpll(minfo, mnp + 0x0300, pll) &&
283 			    g450_testpll(minfo, mnp - 0x0200, pll) &&
284 			    g450_testpll(minfo, mnp + 0x0200, pll) &&
285 			    g450_testpll(minfo, mnp - 0x0100, pll) &&
286 			    g450_testpll(minfo, mnp + 0x0100, pll)) {
287 				if (g450_testpll(minfo, mnp, pll)) {
288 					return mnp;
289 				}
290 			} else if (!found && g450_testpll(minfo, mnp, pll)) {
291 				mnpfound = mnp;
292 				found = 1;
293 			}
294 		}
295 	}
296 	g450_setpll(minfo, mnpfound, pll);
297 	return mnpfound;
298 }
299 
300 static void g450_addcache(struct matrox_pll_cache* ci, unsigned int mnp_key, unsigned int mnp_value) {
301 	if (++ci->valid > ARRAY_SIZE(ci->data)) {
302 		ci->valid = ARRAY_SIZE(ci->data);
303 	}
304 	memmove(ci->data + 1, ci->data, (ci->valid - 1) * sizeof(*ci->data));
305 	ci->data[0].mnp_key = mnp_key & G450_MNP_FREQBITS;
306 	ci->data[0].mnp_value = mnp_value;
307 }
308 
309 static int g450_checkcache(struct matrox_fb_info *minfo,
310 			   struct matrox_pll_cache *ci, unsigned int mnp_key)
311 {
312 	unsigned int i;
313 
314 	mnp_key &= G450_MNP_FREQBITS;
315 	for (i = 0; i < ci->valid; i++) {
316 		if (ci->data[i].mnp_key == mnp_key) {
317 			unsigned int mnp;
318 
319 			mnp = ci->data[i].mnp_value;
320 			if (i) {
321 				memmove(ci->data + 1, ci->data, i * sizeof(*ci->data));
322 				ci->data[0].mnp_key = mnp_key;
323 				ci->data[0].mnp_value = mnp;
324 			}
325 			return mnp;
326 		}
327 	}
328 	return NO_MORE_MNP;
329 }
330 
331 static int __g450_setclk(struct matrox_fb_info *minfo, unsigned int fout,
332 			 unsigned int pll, unsigned int *mnparray,
333 			 unsigned int *deltaarray)
334 {
335 	unsigned int mnpcount;
336 	const struct matrox_pll_limits* pi;
337 	struct matrox_pll_cache* ci;
338 
339 	switch (pll) {
340 		case M_PIXEL_PLL_A:
341 		case M_PIXEL_PLL_B:
342 		case M_PIXEL_PLL_C:
343 			{
344 				u_int8_t tmp, xpwrctrl;
345 				unsigned long flags;
346 
347 				matroxfb_DAC_lock_irqsave(flags);
348 
349 				xpwrctrl = matroxfb_DAC_in(minfo, M1064_XPWRCTRL);
350 				matroxfb_DAC_out(minfo, M1064_XPWRCTRL, xpwrctrl & ~M1064_XPWRCTRL_PANELPDN);
351 				mga_outb(M_SEQ_INDEX, M_SEQ1);
352 				mga_outb(M_SEQ_DATA, mga_inb(M_SEQ_DATA) | M_SEQ1_SCROFF);
353 				tmp = matroxfb_DAC_in(minfo, M1064_XPIXCLKCTRL);
354 				tmp |= M1064_XPIXCLKCTRL_DIS;
355 				if (!(tmp & M1064_XPIXCLKCTRL_PLL_UP)) {
356 					tmp |= M1064_XPIXCLKCTRL_PLL_UP;
357 				}
358 				matroxfb_DAC_out(minfo, M1064_XPIXCLKCTRL, tmp);
359 				/* DVI PLL preferred for frequencies up to
360 				   panel link max, standard PLL otherwise */
361 				if (fout >= minfo->max_pixel_clock_panellink)
362 					tmp = 0;
363 				else tmp =
364 					M1064_XDVICLKCTRL_DVIDATAPATHSEL |
365 					M1064_XDVICLKCTRL_C1DVICLKSEL |
366 					M1064_XDVICLKCTRL_C1DVICLKEN |
367 					M1064_XDVICLKCTRL_DVILOOPCTL |
368 					M1064_XDVICLKCTRL_P1LOOPBWDTCTL;
369                                 /* Setting this breaks PC systems so don't do it */
370 				/* matroxfb_DAC_out(minfo, M1064_XDVICLKCTRL, tmp); */
371 				matroxfb_DAC_out(minfo, M1064_XPWRCTRL,
372 						 xpwrctrl);
373 
374 				matroxfb_DAC_unlock_irqrestore(flags);
375 			}
376 			{
377 				u_int8_t misc;
378 
379 				misc = mga_inb(M_MISC_REG_READ) & ~0x0C;
380 				switch (pll) {
381 					case M_PIXEL_PLL_A:
382 						break;
383 					case M_PIXEL_PLL_B:
384 						misc |=  0x04;
385 						break;
386 					default:
387 						misc |=  0x0C;
388 						break;
389 				}
390 				mga_outb(M_MISC_REG, misc);
391 			}
392 			pi = &minfo->limits.pixel;
393 			ci = &minfo->cache.pixel;
394 			break;
395 		case M_SYSTEM_PLL:
396 			{
397 				u_int32_t opt;
398 
399 				pci_read_config_dword(minfo->pcidev, PCI_OPTION_REG, &opt);
400 				if (!(opt & 0x20)) {
401 					pci_write_config_dword(minfo->pcidev, PCI_OPTION_REG, opt | 0x20);
402 				}
403 			}
404 			pi = &minfo->limits.system;
405 			ci = &minfo->cache.system;
406 			break;
407 		case M_VIDEO_PLL:
408 			{
409 				u_int8_t tmp;
410 				unsigned int mnp;
411 				unsigned long flags;
412 
413 				matroxfb_DAC_lock_irqsave(flags);
414 				tmp = matroxfb_DAC_in(minfo, M1064_XPWRCTRL);
415 				if (!(tmp & 2)) {
416 					matroxfb_DAC_out(minfo, M1064_XPWRCTRL, tmp | 2);
417 				}
418 
419 				mnp = matroxfb_DAC_in(minfo, M1064_XPIXPLLCM) << 16;
420 				mnp |= matroxfb_DAC_in(minfo, M1064_XPIXPLLCN) << 8;
421 				matroxfb_DAC_unlock_irqrestore(flags);
422 			}
423 			pi = &minfo->limits.video;
424 			ci = &minfo->cache.video;
425 			break;
426 		default:
427 			return -EINVAL;
428 	}
429 
430 	mnpcount = 0;
431 	{
432 		unsigned int mnp;
433 		unsigned int xvco;
434 
435 		for (mnp = g450_firstpll(minfo, pi, &xvco, fout); mnp != NO_MORE_MNP; mnp = g450_nextpll(minfo, pi, &xvco, mnp)) {
436 			unsigned int idx;
437 			unsigned int vco;
438 			unsigned int delta;
439 
440 			vco = g450_mnp2vco(minfo, mnp);
441 			delta = pll_freq_delta(fout, g450_vco2f(mnp, vco));
442 			for (idx = mnpcount; idx > 0; idx--) {
443 				/* == is important; due to nextpll algorithm we get
444 				   sorted equally good frequencies from lower VCO
445 				   frequency to higher - with <= lowest wins, while
446 				   with < highest one wins */
447 				if (delta <= deltaarray[idx-1]) {
448 					/* all else being equal except VCO,
449 					 * choose VCO not near (within 1/16th or so) VCOmin
450 					 * (freqs near VCOmin aren't as stable)
451 					 */
452 					if (delta == deltaarray[idx-1]
453 					    && vco != g450_mnp2vco(minfo, mnparray[idx-1])
454 					    && vco < (pi->vcomin * 17 / 16)) {
455 						break;
456 					}
457 					mnparray[idx] = mnparray[idx-1];
458 					deltaarray[idx] = deltaarray[idx-1];
459 				} else {
460 					break;
461 				}
462 			}
463 			mnparray[idx] = mnp;
464 			deltaarray[idx] = delta;
465 			mnpcount++;
466 		}
467 	}
468 	/* VideoPLL and PixelPLL matched: do nothing... In all other cases we should get at least one frequency */
469 	if (!mnpcount) {
470 		return -EBUSY;
471 	}
472 	{
473 		unsigned long flags;
474 		unsigned int mnp;
475 
476 		matroxfb_DAC_lock_irqsave(flags);
477 		mnp = g450_checkcache(minfo, ci, mnparray[0]);
478 		if (mnp != NO_MORE_MNP) {
479 			matroxfb_g450_setpll_cond(minfo, mnp, pll);
480 		} else {
481 			mnp = g450_findworkingpll(minfo, pll, mnparray, mnpcount);
482 			g450_addcache(ci, mnparray[0], mnp);
483 		}
484 		updatehwstate_clk(&minfo->hw, mnp, pll);
485 		matroxfb_DAC_unlock_irqrestore(flags);
486 		return mnp;
487 	}
488 }
489 
490 /* It must be greater than number of possible PLL values.
491  * Currently there is 5(p) * 10(m) = 50 possible values. */
492 #define MNP_TABLE_SIZE  64
493 
494 int matroxfb_g450_setclk(struct matrox_fb_info *minfo, unsigned int fout,
495 			 unsigned int pll)
496 {
497 	unsigned int* arr;
498 
499 	arr = kmalloc(sizeof(*arr) * MNP_TABLE_SIZE * 2, GFP_KERNEL);
500 	if (arr) {
501 		int r;
502 
503 		r = __g450_setclk(minfo, fout, pll, arr, arr + MNP_TABLE_SIZE);
504 		kfree(arr);
505 		return r;
506 	}
507 	return -ENOMEM;
508 }
509 
510 EXPORT_SYMBOL(matroxfb_g450_setclk);
511 EXPORT_SYMBOL(g450_mnp2f);
512 EXPORT_SYMBOL(matroxfb_g450_setpll_cond);
513 
514 MODULE_AUTHOR("(c) 2001-2002 Petr Vandrovec <vandrove@vc.cvut.cz>");
515 MODULE_DESCRIPTION("Matrox G450/G550 PLL driver");
516 
517 MODULE_LICENSE("GPL");
518