1
2/*
3 *  ATI Mach64 CT/VT/GT/LT Support
4 */
5
6#include <linux/fb.h>
7#include <linux/delay.h>
8#include <asm/io.h>
9#include <video/mach64.h>
10#include "atyfb.h"
11#ifdef CONFIG_PPC
12#include <asm/machdep.h>
13#endif
14
15#undef DEBUG
16
17static int aty_valid_pll_ct (const struct fb_info *info, u32 vclk_per, struct pll_ct *pll);
18static int aty_dsp_gt       (const struct fb_info *info, u32 bpp, struct pll_ct *pll);
19static int aty_var_to_pll_ct(const struct fb_info *info, u32 vclk_per, u32 bpp, union aty_pll *pll);
20static u32 aty_pll_to_var_ct(const struct fb_info *info, const union aty_pll *pll);
21
22u8 aty_ld_pll_ct(int offset, const struct atyfb_par *par)
23{
24	u8 res;
25
26	/* write addr byte */
27	aty_st_8(CLOCK_CNTL_ADDR, (offset << 2) & PLL_ADDR, par);
28	/* read the register value */
29	res = aty_ld_8(CLOCK_CNTL_DATA, par);
30	return res;
31}
32
33static void aty_st_pll_ct(int offset, u8 val, const struct atyfb_par *par)
34{
35	/* write addr byte */
36	aty_st_8(CLOCK_CNTL_ADDR, ((offset << 2) & PLL_ADDR) | PLL_WR_EN, par);
37	/* write the register value */
38	aty_st_8(CLOCK_CNTL_DATA, val & PLL_DATA, par);
39	aty_st_8(CLOCK_CNTL_ADDR, ((offset << 2) & PLL_ADDR) & ~PLL_WR_EN, par);
40}
41
42/*
43 * by Daniel Mantione
44 *                                  <daniel.mantione@freepascal.org>
45 *
46 *
47 * ATI Mach64 CT clock synthesis description.
48 *
49 * All clocks on the Mach64 can be calculated using the same principle:
50 *
51 *       XTALIN * x * FB_DIV
52 * CLK = ----------------------
53 *       PLL_REF_DIV * POST_DIV
54 *
55 * XTALIN is a fixed speed clock. Common speeds are 14.31 MHz and 29.50 MHz.
56 * PLL_REF_DIV can be set by the user, but is the same for all clocks.
57 * FB_DIV can be set by the user for each clock individually, it should be set
58 * between 128 and 255, the chip will generate a bad clock signal for too low
59 * values.
60 * x depends on the type of clock; usually it is 2, but for the MCLK it can also
61 * be set to 4.
62 * POST_DIV can be set by the user for each clock individually, Possible values
63 * are 1,2,4,8 and for some clocks other values are available too.
64 * CLK is of course the clock speed that is generated.
65 *
66 * The Mach64 has these clocks:
67 *
68 * MCLK			The clock rate of the chip
69 * XCLK			The clock rate of the on-chip memory
70 * VCLK0		First pixel clock of first CRT controller
71 * VCLK1    Second pixel clock of first CRT controller
72 * VCLK2		Third pixel clock of first CRT controller
73 * VCLK3    Fourth pixel clock of first CRT controller
74 * VCLK			Selected pixel clock, one of VCLK0, VCLK1, VCLK2, VCLK3
75 * V2CLK		Pixel clock of the second CRT controller.
76 * SCLK			Multi-purpose clock
77 *
78 * - MCLK and XCLK use the same FB_DIV
79 * - VCLK0 .. VCLK3 use the same FB_DIV
80 * - V2CLK is needed when the second CRTC is used (can be used for dualhead);
81 *   i.e. CRT monitor connected to laptop has different resolution than built
82 *   in LCD monitor.
83 * - SCLK is not available on all cards; it is know to exist on the Rage LT-PRO,
84 *   Rage XL and Rage Mobility. It is know not to exist on the Mach64 VT.
85 * - V2CLK is not available on all cards, most likely only the Rage LT-PRO,
86 *   the Rage XL and the Rage Mobility
87 *
88 * SCLK can be used to:
89 * - Clock the chip instead of MCLK
90 * - Replace XTALIN with a user defined frequency
91 * - Generate the pixel clock for the LCD monitor (instead of VCLK)
92 */
93
94 /*
95  * It can be quite hard to calculate XCLK and MCLK if they don't run at the
96  * same frequency. Luckily, until now all cards that need asynchrone clock
97  * speeds seem to have SCLK.
98  * So this driver uses SCLK to clock the chip and XCLK to clock the memory.
99  */
100
101/* ------------------------------------------------------------------------- */
102
103/*
104 *  PLL programming (Mach64 CT family)
105 *
106 *
107 * This procedure sets the display fifo. The display fifo is a buffer that
108 * contains data read from the video memory that waits to be processed by
109 * the CRT controller.
110 *
111 * On the more modern Mach64 variants, the chip doesn't calculate the
112 * interval after which the display fifo has to be reloaded from memory
113 * automatically, the driver has to do it instead.
114 */
115
116#define Maximum_DSP_PRECISION 7
117static u8 postdividers[] = {1,2,4,8,3};
118
119static int aty_dsp_gt(const struct fb_info *info, u32 bpp, struct pll_ct *pll)
120{
121	u32 dsp_off, dsp_on, dsp_xclks;
122	u32 multiplier, divider, ras_multiplier, ras_divider, tmp;
123	u8 vshift, xshift;
124	s8 dsp_precision;
125
126	multiplier = ((u32)pll->mclk_fb_div) * pll->vclk_post_div_real;
127	divider = ((u32)pll->vclk_fb_div) * pll->xclk_ref_div;
128
129	ras_multiplier = pll->xclkmaxrasdelay;
130	ras_divider = 1;
131
132	if (bpp>=8)
133		divider = divider * (bpp >> 2);
134
135	vshift = (6 - 2) - pll->xclk_post_div;	/* FIFO is 64 bits wide in accelerator mode ... */
136
137	if (bpp == 0)
138		vshift--;	/* ... but only 32 bits in VGA mode. */
139
140#ifdef CONFIG_FB_ATY_GENERIC_LCD
141	if (pll->xres != 0) {
142		struct atyfb_par *par = (struct atyfb_par *) info->par;
143
144		multiplier = multiplier * par->lcd_width;
145		divider = divider * pll->xres & ~7;
146
147		ras_multiplier = ras_multiplier * par->lcd_width;
148		ras_divider = ras_divider * pll->xres & ~7;
149	}
150#endif
151	/* If we don't do this, 32 bits for multiplier & divider won't be
152	enough in certain situations! */
153	while (((multiplier | divider) & 1) == 0) {
154		multiplier = multiplier >> 1;
155		divider = divider >> 1;
156	}
157
158	/* Determine DSP precision first */
159	tmp = ((multiplier * pll->fifo_size) << vshift) / divider;
160
161	for (dsp_precision = -5;  tmp;  dsp_precision++)
162		tmp >>= 1;
163	if (dsp_precision < 0)
164		dsp_precision = 0;
165	else if (dsp_precision > Maximum_DSP_PRECISION)
166		dsp_precision = Maximum_DSP_PRECISION;
167
168	xshift = 6 - dsp_precision;
169	vshift += xshift;
170
171	/* Move on to dsp_off */
172	dsp_off = ((multiplier * (pll->fifo_size - 1)) << vshift) / divider -
173		(1 << (vshift - xshift));
174
175/*    if (bpp == 0)
176        dsp_on = ((multiplier * 20 << vshift) + divider) / divider;
177    else */
178	{
179		dsp_on = ((multiplier << vshift) + divider) / divider;
180		tmp = ((ras_multiplier << xshift) + ras_divider) / ras_divider;
181		if (dsp_on < tmp)
182		dsp_on = tmp;
183		dsp_on = dsp_on + (tmp * 2) + (pll->xclkpagefaultdelay << xshift);
184	}
185
186	/* Calculate rounding factor and apply it to dsp_on */
187	tmp = ((1 << (Maximum_DSP_PRECISION - dsp_precision)) - 1) >> 1;
188	dsp_on = ((dsp_on + tmp) / (tmp + 1)) * (tmp + 1);
189
190	if (dsp_on >= ((dsp_off / (tmp + 1)) * (tmp + 1))) {
191		dsp_on = dsp_off - (multiplier << vshift) / divider;
192		dsp_on = (dsp_on / (tmp + 1)) * (tmp + 1);
193	}
194
195	/* Last but not least:  dsp_xclks */
196	dsp_xclks = ((multiplier << (vshift + 5)) + divider) / divider;
197
198	/* Get register values. */
199	pll->dsp_on_off = (dsp_on << 16) + dsp_off;
200	pll->dsp_config = (dsp_precision << 20) | (pll->dsp_loop_latency << 16) | dsp_xclks;
201#ifdef DEBUG
202	printk("atyfb(%s): dsp_config 0x%08x, dsp_on_off 0x%08x\n",
203		__func__, pll->dsp_config, pll->dsp_on_off);
204#endif
205	return 0;
206}
207
208static int aty_valid_pll_ct(const struct fb_info *info, u32 vclk_per, struct pll_ct *pll)
209{
210	u32 q;
211	struct atyfb_par *par = (struct atyfb_par *) info->par;
212	int pllvclk;
213
214	/* FIXME: use the VTB/GTB /{3,6,12} post dividers if they're better suited */
215	q = par->ref_clk_per * pll->pll_ref_div * 4 / vclk_per;
216	if (q < 16*8 || q > 255*8) {
217		printk(KERN_CRIT "atyfb: vclk out of range\n");
218		return -EINVAL;
219	} else {
220		pll->vclk_post_div  = (q < 128*8);
221		pll->vclk_post_div += (q <  64*8);
222		pll->vclk_post_div += (q <  32*8);
223	}
224	pll->vclk_post_div_real = postdividers[pll->vclk_post_div];
225	//    pll->vclk_post_div <<= 6;
226	pll->vclk_fb_div = q * pll->vclk_post_div_real / 8;
227	pllvclk = (1000000 * 2 * pll->vclk_fb_div) /
228		(par->ref_clk_per * pll->pll_ref_div);
229#ifdef DEBUG
230	printk("atyfb(%s): pllvclk=%d MHz, vclk=%d MHz\n",
231		__func__, pllvclk, pllvclk / pll->vclk_post_div_real);
232#endif
233	pll->pll_vclk_cntl = 0x03; /* VCLK = PLL_VCLK/VCLKx_POST */
234
235	/* Set ECP (scaler/overlay clock) divider */
236	if (par->pll_limits.ecp_max) {
237		int ecp = pllvclk / pll->vclk_post_div_real;
238		int ecp_div = 0;
239
240		while (ecp > par->pll_limits.ecp_max && ecp_div < 2) {
241			ecp >>= 1;
242			ecp_div++;
243		}
244		pll->pll_vclk_cntl |= ecp_div << 4;
245	}
246
247	return 0;
248}
249
250static int aty_var_to_pll_ct(const struct fb_info *info, u32 vclk_per, u32 bpp, union aty_pll *pll)
251{
252	struct atyfb_par *par = (struct atyfb_par *) info->par;
253	int err;
254
255	if ((err = aty_valid_pll_ct(info, vclk_per, &pll->ct)))
256		return err;
257	if (M64_HAS(GTB_DSP) && (err = aty_dsp_gt(info, bpp, &pll->ct)))
258		return err;
259	/*aty_calc_pll_ct(info, &pll->ct);*/
260	return 0;
261}
262
263static u32 aty_pll_to_var_ct(const struct fb_info *info, const union aty_pll *pll)
264{
265	struct atyfb_par *par = (struct atyfb_par *) info->par;
266	u32 ret;
267	ret = par->ref_clk_per * pll->ct.pll_ref_div * pll->ct.vclk_post_div_real / pll->ct.vclk_fb_div / 2;
268#ifdef CONFIG_FB_ATY_GENERIC_LCD
269	if(pll->ct.xres > 0) {
270		ret *= par->lcd_width;
271		ret /= pll->ct.xres;
272	}
273#endif
274#ifdef DEBUG
275	printk("atyfb(%s): calculated 0x%08X(%i)\n", __func__, ret, ret);
276#endif
277	return ret;
278}
279
280void aty_set_pll_ct(const struct fb_info *info, const union aty_pll *pll)
281{
282	struct atyfb_par *par = (struct atyfb_par *) info->par;
283	u32 crtc_gen_cntl, lcd_gen_cntrl;
284	u8 tmp, tmp2;
285
286	lcd_gen_cntrl = 0;
287#ifdef DEBUG
288	printk("atyfb(%s): about to program:\n"
289		"pll_ext_cntl=0x%02x pll_gen_cntl=0x%02x pll_vclk_cntl=0x%02x\n",
290		__func__,
291		pll->ct.pll_ext_cntl, pll->ct.pll_gen_cntl, pll->ct.pll_vclk_cntl);
292
293	printk("atyfb(%s): setting clock %lu for FeedBackDivider %i, ReferenceDivider %i, PostDivider %i(%i)\n",
294		__func__,
295		par->clk_wr_offset, pll->ct.vclk_fb_div,
296		pll->ct.pll_ref_div, pll->ct.vclk_post_div, pll->ct.vclk_post_div_real);
297#endif
298#ifdef CONFIG_FB_ATY_GENERIC_LCD
299	if (par->lcd_table != 0) {
300		/* turn off LCD */
301		lcd_gen_cntrl = aty_ld_lcd(LCD_GEN_CNTL, par);
302		aty_st_lcd(LCD_GEN_CNTL, lcd_gen_cntrl & ~LCD_ON, par);
303	}
304#endif
305	aty_st_8(CLOCK_CNTL, par->clk_wr_offset | CLOCK_STROBE, par);
306
307	/* Temporarily switch to accelerator mode */
308	crtc_gen_cntl = aty_ld_le32(CRTC_GEN_CNTL, par);
309	if (!(crtc_gen_cntl & CRTC_EXT_DISP_EN))
310		aty_st_le32(CRTC_GEN_CNTL, crtc_gen_cntl | CRTC_EXT_DISP_EN, par);
311
312	/* Reset VCLK generator */
313	aty_st_pll_ct(PLL_VCLK_CNTL, pll->ct.pll_vclk_cntl, par);
314
315	/* Set post-divider */
316	tmp2 = par->clk_wr_offset << 1;
317	tmp = aty_ld_pll_ct(VCLK_POST_DIV, par);
318	tmp &= ~(0x03U << tmp2);
319	tmp |= ((pll->ct.vclk_post_div & 0x03U) << tmp2);
320	aty_st_pll_ct(VCLK_POST_DIV, tmp, par);
321
322	/* Set extended post-divider */
323	tmp = aty_ld_pll_ct(PLL_EXT_CNTL, par);
324	tmp &= ~(0x10U << par->clk_wr_offset);
325	tmp &= 0xF0U;
326	tmp |= pll->ct.pll_ext_cntl;
327	aty_st_pll_ct(PLL_EXT_CNTL, tmp, par);
328
329	/* Set feedback divider */
330	tmp = VCLK0_FB_DIV + par->clk_wr_offset;
331	aty_st_pll_ct(tmp, (pll->ct.vclk_fb_div & 0xFFU), par);
332
333	aty_st_pll_ct(PLL_GEN_CNTL, (pll->ct.pll_gen_cntl & (~(PLL_OVERRIDE | PLL_MCLK_RST))) | OSC_EN, par);
334
335	/* End VCLK generator reset */
336	aty_st_pll_ct(PLL_VCLK_CNTL, pll->ct.pll_vclk_cntl & ~(PLL_VCLK_RST), par);
337	mdelay(5);
338
339	aty_st_pll_ct(PLL_GEN_CNTL, pll->ct.pll_gen_cntl, par);
340	aty_st_pll_ct(PLL_VCLK_CNTL, pll->ct.pll_vclk_cntl, par);
341	mdelay(1);
342
343	/* Restore mode register */
344	if (!(crtc_gen_cntl & CRTC_EXT_DISP_EN))
345		aty_st_le32(CRTC_GEN_CNTL, crtc_gen_cntl, par);
346
347	if (M64_HAS(GTB_DSP)) {
348		u8 dll_cntl;
349
350		if (M64_HAS(XL_DLL))
351			dll_cntl = 0x80;
352		else if (par->ram_type >= SDRAM)
353			dll_cntl = 0xa6;
354		else
355			dll_cntl = 0xa0;
356		aty_st_pll_ct(DLL_CNTL, dll_cntl, par);
357		aty_st_pll_ct(VFC_CNTL, 0x1b, par);
358		aty_st_le32(DSP_CONFIG, pll->ct.dsp_config, par);
359		aty_st_le32(DSP_ON_OFF, pll->ct.dsp_on_off, par);
360
361		mdelay(10);
362		aty_st_pll_ct(DLL_CNTL, dll_cntl, par);
363		mdelay(10);
364		aty_st_pll_ct(DLL_CNTL, dll_cntl | 0x40, par);
365		mdelay(10);
366		aty_st_pll_ct(DLL_CNTL, dll_cntl & ~0x40, par);
367	}
368#ifdef CONFIG_FB_ATY_GENERIC_LCD
369	if (par->lcd_table != 0) {
370		/* restore LCD */
371		aty_st_lcd(LCD_GEN_CNTL, lcd_gen_cntrl, par);
372	}
373#endif
374}
375
376static void aty_get_pll_ct(const struct fb_info *info, union aty_pll *pll)
377{
378	struct atyfb_par *par = (struct atyfb_par *) info->par;
379	u8 tmp, clock;
380
381	clock = aty_ld_8(CLOCK_CNTL, par) & 0x03U;
382	tmp = clock << 1;
383	pll->ct.vclk_post_div = (aty_ld_pll_ct(VCLK_POST_DIV, par) >> tmp) & 0x03U;
384
385	pll->ct.pll_ext_cntl = aty_ld_pll_ct(PLL_EXT_CNTL, par) & 0x0FU;
386	pll->ct.vclk_fb_div = aty_ld_pll_ct(VCLK0_FB_DIV + clock, par) & 0xFFU;
387	pll->ct.pll_ref_div = aty_ld_pll_ct(PLL_REF_DIV, par);
388	pll->ct.mclk_fb_div = aty_ld_pll_ct(MCLK_FB_DIV, par);
389
390	pll->ct.pll_gen_cntl = aty_ld_pll_ct(PLL_GEN_CNTL, par);
391	pll->ct.pll_vclk_cntl = aty_ld_pll_ct(PLL_VCLK_CNTL, par);
392
393	if (M64_HAS(GTB_DSP)) {
394		pll->ct.dsp_config = aty_ld_le32(DSP_CONFIG, par);
395		pll->ct.dsp_on_off = aty_ld_le32(DSP_ON_OFF, par);
396	}
397}
398
399static int aty_init_pll_ct(const struct fb_info *info, union aty_pll *pll)
400{
401	struct atyfb_par *par = (struct atyfb_par *) info->par;
402	u8 mpost_div, xpost_div, sclk_post_div_real;
403	u32 q, memcntl, trp;
404	u32 dsp_config, dsp_on_off, vga_dsp_config, vga_dsp_on_off;
405#ifdef DEBUG
406	int pllmclk, pllsclk;
407#endif
408	pll->ct.pll_ext_cntl = aty_ld_pll_ct(PLL_EXT_CNTL, par);
409	pll->ct.xclk_post_div = pll->ct.pll_ext_cntl & 0x07;
410	pll->ct.xclk_ref_div = 1;
411	switch (pll->ct.xclk_post_div) {
412	case 0:  case 1:  case 2:  case 3:
413		break;
414
415	case 4:
416		pll->ct.xclk_ref_div = 3;
417		pll->ct.xclk_post_div = 0;
418		break;
419
420	default:
421		printk(KERN_CRIT "atyfb: Unsupported xclk source:  %d.\n", pll->ct.xclk_post_div);
422		return -EINVAL;
423	}
424	pll->ct.mclk_fb_mult = 2;
425	if(pll->ct.pll_ext_cntl & PLL_MFB_TIMES_4_2B) {
426		pll->ct.mclk_fb_mult = 4;
427		pll->ct.xclk_post_div -= 1;
428	}
429
430#ifdef DEBUG
431	printk("atyfb(%s): mclk_fb_mult=%d, xclk_post_div=%d\n",
432		__func__, pll->ct.mclk_fb_mult, pll->ct.xclk_post_div);
433#endif
434
435	memcntl = aty_ld_le32(MEM_CNTL, par);
436	trp = (memcntl & 0x300) >> 8;
437
438	pll->ct.xclkpagefaultdelay = ((memcntl & 0xc00) >> 10) + ((memcntl & 0x1000) >> 12) + trp + 2;
439	pll->ct.xclkmaxrasdelay = ((memcntl & 0x70000) >> 16) + trp + 2;
440
441	if (M64_HAS(FIFO_32)) {
442		pll->ct.fifo_size = 32;
443	} else {
444		pll->ct.fifo_size = 24;
445		pll->ct.xclkpagefaultdelay += 2;
446		pll->ct.xclkmaxrasdelay += 3;
447	}
448
449	switch (par->ram_type) {
450	case DRAM:
451		if (info->fix.smem_len<=ONE_MB) {
452			pll->ct.dsp_loop_latency = 10;
453		} else {
454			pll->ct.dsp_loop_latency = 8;
455			pll->ct.xclkpagefaultdelay += 2;
456		}
457		break;
458	case EDO:
459	case PSEUDO_EDO:
460		if (info->fix.smem_len<=ONE_MB) {
461			pll->ct.dsp_loop_latency = 9;
462		} else {
463			pll->ct.dsp_loop_latency = 8;
464			pll->ct.xclkpagefaultdelay += 1;
465		}
466		break;
467	case SDRAM:
468		if (info->fix.smem_len<=ONE_MB) {
469			pll->ct.dsp_loop_latency = 11;
470		} else {
471			pll->ct.dsp_loop_latency = 10;
472			pll->ct.xclkpagefaultdelay += 1;
473		}
474		break;
475	case SGRAM:
476		pll->ct.dsp_loop_latency = 8;
477		pll->ct.xclkpagefaultdelay += 3;
478		break;
479	default:
480		pll->ct.dsp_loop_latency = 11;
481		pll->ct.xclkpagefaultdelay += 3;
482		break;
483	}
484
485	if (pll->ct.xclkmaxrasdelay <= pll->ct.xclkpagefaultdelay)
486		pll->ct.xclkmaxrasdelay = pll->ct.xclkpagefaultdelay + 1;
487
488	/* Allow BIOS to override */
489	dsp_config = aty_ld_le32(DSP_CONFIG, par);
490	dsp_on_off = aty_ld_le32(DSP_ON_OFF, par);
491	vga_dsp_config = aty_ld_le32(VGA_DSP_CONFIG, par);
492	vga_dsp_on_off = aty_ld_le32(VGA_DSP_ON_OFF, par);
493
494	if (dsp_config)
495		pll->ct.dsp_loop_latency = (dsp_config & DSP_LOOP_LATENCY) >> 16;
496#if 0
497	FIXME: is it relevant for us?
498	if ((!dsp_on_off && !M64_HAS(RESET_3D)) ||
499		((dsp_on_off == vga_dsp_on_off) &&
500		(!dsp_config || !((dsp_config ^ vga_dsp_config) & DSP_XCLKS_PER_QW)))) {
501		vga_dsp_on_off &= VGA_DSP_OFF;
502		vga_dsp_config &= VGA_DSP_XCLKS_PER_QW;
503		if (ATIDivide(vga_dsp_on_off, vga_dsp_config, 5, 1) > 24)
504			pll->ct.fifo_size = 32;
505		else
506			pll->ct.fifo_size = 24;
507	}
508#endif
509	/* Exit if the user does not want us to tamper with the clock
510	rates of her chip. */
511	if (par->mclk_per == 0) {
512		u8 mclk_fb_div, pll_ext_cntl;
513		pll->ct.pll_ref_div = aty_ld_pll_ct(PLL_REF_DIV, par);
514		pll_ext_cntl = aty_ld_pll_ct(PLL_EXT_CNTL, par);
515		pll->ct.xclk_post_div_real = postdividers[pll_ext_cntl & 0x07];
516		mclk_fb_div = aty_ld_pll_ct(MCLK_FB_DIV, par);
517		if (pll_ext_cntl & PLL_MFB_TIMES_4_2B)
518			mclk_fb_div <<= 1;
519		pll->ct.mclk_fb_div = mclk_fb_div;
520		return 0;
521	}
522
523	pll->ct.pll_ref_div = par->pll_per * 2 * 255 / par->ref_clk_per;
524
525	/* FIXME: use the VTB/GTB /3 post divider if it's better suited */
526	q = par->ref_clk_per * pll->ct.pll_ref_div * 8 /
527		(pll->ct.mclk_fb_mult * par->xclk_per);
528
529	if (q < 16*8 || q > 255*8) {
530		printk(KERN_CRIT "atxfb: xclk out of range\n");
531		return -EINVAL;
532	} else {
533		xpost_div  = (q < 128*8);
534		xpost_div += (q <  64*8);
535		xpost_div += (q <  32*8);
536	}
537	pll->ct.xclk_post_div_real = postdividers[xpost_div];
538	pll->ct.mclk_fb_div = q * pll->ct.xclk_post_div_real / 8;
539
540#ifdef CONFIG_PPC
541	if (machine_is(powermac)) {
542		/* Override PLL_EXT_CNTL & 0x07. */
543		pll->ct.xclk_post_div = xpost_div;
544		pll->ct.xclk_ref_div = 1;
545	}
546#endif
547
548#ifdef DEBUG
549	pllmclk = (1000000 * pll->ct.mclk_fb_mult * pll->ct.mclk_fb_div) /
550			(par->ref_clk_per * pll->ct.pll_ref_div);
551	printk("atyfb(%s): pllmclk=%d MHz, xclk=%d MHz\n",
552		__func__, pllmclk, pllmclk / pll->ct.xclk_post_div_real);
553#endif
554
555	if (M64_HAS(SDRAM_MAGIC_PLL) && (par->ram_type >= SDRAM))
556		pll->ct.pll_gen_cntl = OSC_EN;
557	else
558		pll->ct.pll_gen_cntl = OSC_EN | DLL_PWDN /* | FORCE_DCLK_TRI_STATE */;
559
560	if (M64_HAS(MAGIC_POSTDIV))
561		pll->ct.pll_ext_cntl = 0;
562	else
563		pll->ct.pll_ext_cntl = xpost_div;
564
565	if (pll->ct.mclk_fb_mult == 4)
566		pll->ct.pll_ext_cntl |= PLL_MFB_TIMES_4_2B;
567
568	if (par->mclk_per == par->xclk_per) {
569		pll->ct.pll_gen_cntl |= (xpost_div << 4); /* mclk == xclk */
570	} else {
571		/*
572		* The chip clock is not equal to the memory clock.
573		* Therefore we will use sclk to clock the chip.
574		*/
575		pll->ct.pll_gen_cntl |= (6 << 4); /* mclk == sclk */
576
577		q = par->ref_clk_per * pll->ct.pll_ref_div * 4 / par->mclk_per;
578		if (q < 16*8 || q > 255*8) {
579			printk(KERN_CRIT "atyfb: mclk out of range\n");
580			return -EINVAL;
581		} else {
582			mpost_div  = (q < 128*8);
583			mpost_div += (q <  64*8);
584			mpost_div += (q <  32*8);
585		}
586		sclk_post_div_real = postdividers[mpost_div];
587		pll->ct.sclk_fb_div = q * sclk_post_div_real / 8;
588		pll->ct.spll_cntl2 = mpost_div << 4;
589#ifdef DEBUG
590		pllsclk = (1000000 * 2 * pll->ct.sclk_fb_div) /
591			(par->ref_clk_per * pll->ct.pll_ref_div);
592		printk("atyfb(%s): use sclk, pllsclk=%d MHz, sclk=mclk=%d MHz\n",
593			__func__, pllsclk, pllsclk / sclk_post_div_real);
594#endif
595	}
596
597	/* Disable the extra precision pixel clock controls since we do not use them. */
598	pll->ct.ext_vpll_cntl = aty_ld_pll_ct(EXT_VPLL_CNTL, par);
599	pll->ct.ext_vpll_cntl &= ~(EXT_VPLL_EN | EXT_VPLL_VGA_EN | EXT_VPLL_INSYNC);
600
601	return 0;
602}
603
604static void aty_resume_pll_ct(const struct fb_info *info,
605			      union aty_pll *pll)
606{
607	struct atyfb_par *par = info->par;
608
609	if (par->mclk_per != par->xclk_per) {
610		/*
611		* This disables the sclk, crashes the computer as reported:
612		* aty_st_pll_ct(SPLL_CNTL2, 3, info);
613		*
614		* So it seems the sclk must be enabled before it is used;
615		* so PLL_GEN_CNTL must be programmed *after* the sclk.
616		*/
617		aty_st_pll_ct(SCLK_FB_DIV, pll->ct.sclk_fb_div, par);
618		aty_st_pll_ct(SPLL_CNTL2, pll->ct.spll_cntl2, par);
619		/*
620		 * SCLK has been started. Wait for the PLL to lock. 5 ms
621		 * should be enough according to mach64 programmer's guide.
622		 */
623		mdelay(5);
624	}
625
626	aty_st_pll_ct(PLL_REF_DIV, pll->ct.pll_ref_div, par);
627	aty_st_pll_ct(PLL_GEN_CNTL, pll->ct.pll_gen_cntl, par);
628	aty_st_pll_ct(MCLK_FB_DIV, pll->ct.mclk_fb_div, par);
629	aty_st_pll_ct(PLL_EXT_CNTL, pll->ct.pll_ext_cntl, par);
630	aty_st_pll_ct(EXT_VPLL_CNTL, pll->ct.ext_vpll_cntl, par);
631}
632
633static int dummy(void)
634{
635	return 0;
636}
637
638const struct aty_dac_ops aty_dac_ct = {
639	.set_dac	= (void *) dummy,
640};
641
642const struct aty_pll_ops aty_pll_ct = {
643	.var_to_pll	= aty_var_to_pll_ct,
644	.pll_to_var	= aty_pll_to_var_ct,
645	.set_pll	= aty_set_pll_ct,
646	.get_pll	= aty_get_pll_ct,
647	.init_pll	= aty_init_pll_ct,
648	.resume_pll	= aty_resume_pll_ct,
649};
650