1// SPDX-License-Identifier: GPL-2.0
2
3/*
4 *  ATI Mach64 CT/VT/GT/LT Support
5 */
6
7#include <linux/fb.h>
8#include <linux/delay.h>
9#include <asm/io.h>
10#include <video/mach64.h>
11#include "atyfb.h"
12#ifdef CONFIG_PPC
13#include <asm/machdep.h>
14#endif
15
16#undef DEBUG
17
18static int aty_valid_pll_ct (const struct fb_info *info, u32 vclk_per, struct pll_ct *pll);
19static int aty_dsp_gt       (const struct fb_info *info, u32 bpp, struct pll_ct *pll);
20static int aty_var_to_pll_ct(const struct fb_info *info, u32 vclk_per, u32 bpp, union aty_pll *pll);
21static u32 aty_pll_to_var_ct(const struct fb_info *info, const union aty_pll *pll);
22
23u8 aty_ld_pll_ct(int offset, const struct atyfb_par *par)
24{
25	u8 res;
26
27	/* write addr byte */
28	aty_st_8(CLOCK_CNTL_ADDR, (offset << 2) & PLL_ADDR, par);
29	/* read the register value */
30	res = aty_ld_8(CLOCK_CNTL_DATA, par);
31	return res;
32}
33
34static void aty_st_pll_ct(int offset, u8 val, const struct atyfb_par *par)
35{
36	/* write addr byte */
37	aty_st_8(CLOCK_CNTL_ADDR, ((offset << 2) & PLL_ADDR) | PLL_WR_EN, par);
38	/* write the register value */
39	aty_st_8(CLOCK_CNTL_DATA, val & PLL_DATA, par);
40	aty_st_8(CLOCK_CNTL_ADDR, ((offset << 2) & PLL_ADDR) & ~PLL_WR_EN, par);
41}
42
43/*
44 * by Daniel Mantione
45 *                                  <daniel.mantione@freepascal.org>
46 *
47 *
48 * ATI Mach64 CT clock synthesis description.
49 *
50 * All clocks on the Mach64 can be calculated using the same principle:
51 *
52 *       XTALIN * x * FB_DIV
53 * CLK = ----------------------
54 *       PLL_REF_DIV * POST_DIV
55 *
56 * XTALIN is a fixed speed clock. Common speeds are 14.31 MHz and 29.50 MHz.
57 * PLL_REF_DIV can be set by the user, but is the same for all clocks.
58 * FB_DIV can be set by the user for each clock individually, it should be set
59 * between 128 and 255, the chip will generate a bad clock signal for too low
60 * values.
61 * x depends on the type of clock; usually it is 2, but for the MCLK it can also
62 * be set to 4.
63 * POST_DIV can be set by the user for each clock individually, Possible values
64 * are 1,2,4,8 and for some clocks other values are available too.
65 * CLK is of course the clock speed that is generated.
66 *
67 * The Mach64 has these clocks:
68 *
69 * MCLK			The clock rate of the chip
70 * XCLK			The clock rate of the on-chip memory
71 * VCLK0		First pixel clock of first CRT controller
72 * VCLK1    Second pixel clock of first CRT controller
73 * VCLK2		Third pixel clock of first CRT controller
74 * VCLK3    Fourth pixel clock of first CRT controller
75 * VCLK			Selected pixel clock, one of VCLK0, VCLK1, VCLK2, VCLK3
76 * V2CLK		Pixel clock of the second CRT controller.
77 * SCLK			Multi-purpose clock
78 *
79 * - MCLK and XCLK use the same FB_DIV
80 * - VCLK0 .. VCLK3 use the same FB_DIV
81 * - V2CLK is needed when the second CRTC is used (can be used for dualhead);
82 *   i.e. CRT monitor connected to laptop has different resolution than built
83 *   in LCD monitor.
84 * - SCLK is not available on all cards; it is know to exist on the Rage LT-PRO,
85 *   Rage XL and Rage Mobility. It is know not to exist on the Mach64 VT.
86 * - V2CLK is not available on all cards, most likely only the Rage LT-PRO,
87 *   the Rage XL and the Rage Mobility
88 *
89 * SCLK can be used to:
90 * - Clock the chip instead of MCLK
91 * - Replace XTALIN with a user defined frequency
92 * - Generate the pixel clock for the LCD monitor (instead of VCLK)
93 */
94
95 /*
96  * It can be quite hard to calculate XCLK and MCLK if they don't run at the
97  * same frequency. Luckily, until now all cards that need asynchrone clock
98  * speeds seem to have SCLK.
99  * So this driver uses SCLK to clock the chip and XCLK to clock the memory.
100  */
101
102/* ------------------------------------------------------------------------- */
103
104/*
105 *  PLL programming (Mach64 CT family)
106 *
107 *
108 * This procedure sets the display fifo. The display fifo is a buffer that
109 * contains data read from the video memory that waits to be processed by
110 * the CRT controller.
111 *
112 * On the more modern Mach64 variants, the chip doesn't calculate the
113 * interval after which the display fifo has to be reloaded from memory
114 * automatically, the driver has to do it instead.
115 */
116
117#define Maximum_DSP_PRECISION 7
118const u8 aty_postdividers[8] = {1,2,4,8,3,5,6,12};
119
120static int aty_dsp_gt(const struct fb_info *info, u32 bpp, struct pll_ct *pll)
121{
122	u32 dsp_off, dsp_on, dsp_xclks;
123	u32 multiplier, divider, ras_multiplier, ras_divider, tmp;
124	u8 vshift, xshift;
125	s8 dsp_precision;
126
127	multiplier = ((u32)pll->mclk_fb_div) * pll->vclk_post_div_real;
128	divider = ((u32)pll->vclk_fb_div) * pll->xclk_ref_div;
129
130	ras_multiplier = pll->xclkmaxrasdelay;
131	ras_divider = 1;
132
133	if (bpp>=8)
134		divider = divider * (bpp >> 2);
135
136	vshift = (6 - 2) - pll->xclk_post_div;	/* FIFO is 64 bits wide in accelerator mode ... */
137
138	if (bpp == 0)
139		vshift--;	/* ... but only 32 bits in VGA mode. */
140
141#ifdef CONFIG_FB_ATY_GENERIC_LCD
142	if (pll->xres != 0) {
143		struct atyfb_par *par = (struct atyfb_par *) info->par;
144
145		multiplier = multiplier * par->lcd_width;
146		divider = divider * pll->xres & ~7;
147
148		ras_multiplier = ras_multiplier * par->lcd_width;
149		ras_divider = ras_divider * pll->xres & ~7;
150	}
151#endif
152	/* If we don't do this, 32 bits for multiplier & divider won't be
153	enough in certain situations! */
154	while (((multiplier | divider) & 1) == 0) {
155		multiplier = multiplier >> 1;
156		divider = divider >> 1;
157	}
158
159	/* Determine DSP precision first */
160	tmp = ((multiplier * pll->fifo_size) << vshift) / divider;
161
162	for (dsp_precision = -5;  tmp;  dsp_precision++)
163		tmp >>= 1;
164	if (dsp_precision < 0)
165		dsp_precision = 0;
166	else if (dsp_precision > Maximum_DSP_PRECISION)
167		dsp_precision = Maximum_DSP_PRECISION;
168
169	xshift = 6 - dsp_precision;
170	vshift += xshift;
171
172	/* Move on to dsp_off */
173	dsp_off = ((multiplier * (pll->fifo_size - 1)) << vshift) / divider -
174		(1 << (vshift - xshift));
175
176/*    if (bpp == 0)
177        dsp_on = ((multiplier * 20 << vshift) + divider) / divider;
178    else */
179	{
180		dsp_on = ((multiplier << vshift) + divider) / divider;
181		tmp = ((ras_multiplier << xshift) + ras_divider) / ras_divider;
182		if (dsp_on < tmp)
183			dsp_on = tmp;
184		dsp_on = dsp_on + (tmp * 2) + (pll->xclkpagefaultdelay << xshift);
185	}
186
187	/* Calculate rounding factor and apply it to dsp_on */
188	tmp = ((1 << (Maximum_DSP_PRECISION - dsp_precision)) - 1) >> 1;
189	dsp_on = ((dsp_on + tmp) / (tmp + 1)) * (tmp + 1);
190
191	if (dsp_on >= ((dsp_off / (tmp + 1)) * (tmp + 1))) {
192		dsp_on = dsp_off - (multiplier << vshift) / divider;
193		dsp_on = (dsp_on / (tmp + 1)) * (tmp + 1);
194	}
195
196	/* Last but not least:  dsp_xclks */
197	dsp_xclks = ((multiplier << (vshift + 5)) + divider) / divider;
198
199	/* Get register values. */
200	pll->dsp_on_off = (dsp_on << 16) + dsp_off;
201	pll->dsp_config = (dsp_precision << 20) | (pll->dsp_loop_latency << 16) | dsp_xclks;
202#ifdef DEBUG
203	printk("atyfb(%s): dsp_config 0x%08x, dsp_on_off 0x%08x\n",
204		__func__, pll->dsp_config, pll->dsp_on_off);
205#endif
206	return 0;
207}
208
209static int aty_valid_pll_ct(const struct fb_info *info, u32 vclk_per, struct pll_ct *pll)
210{
211	u32 q;
212	struct atyfb_par *par = (struct atyfb_par *) info->par;
213	int pllvclk;
214
215	/* FIXME: use the VTB/GTB /{3,6,12} post dividers if they're better suited */
216	q = par->ref_clk_per * pll->pll_ref_div * 4 / vclk_per;
217	if (q < 16*8 || q > 255*8) {
218		printk(KERN_CRIT "atyfb: vclk out of range\n");
219		return -EINVAL;
220	} else {
221		pll->vclk_post_div  = (q < 128*8);
222		pll->vclk_post_div += (q <  64*8);
223		pll->vclk_post_div += (q <  32*8);
224	}
225	pll->vclk_post_div_real = aty_postdividers[pll->vclk_post_div];
226	//    pll->vclk_post_div <<= 6;
227	pll->vclk_fb_div = q * pll->vclk_post_div_real / 8;
228	pllvclk = (1000000 * 2 * pll->vclk_fb_div) /
229		(par->ref_clk_per * pll->pll_ref_div);
230#ifdef DEBUG
231	printk("atyfb(%s): pllvclk=%d MHz, vclk=%d MHz\n",
232		__func__, pllvclk, pllvclk / pll->vclk_post_div_real);
233#endif
234	pll->pll_vclk_cntl = 0x03; /* VCLK = PLL_VCLK/VCLKx_POST */
235
236	/* Set ECP (scaler/overlay clock) divider */
237	if (par->pll_limits.ecp_max) {
238		int ecp = pllvclk / pll->vclk_post_div_real;
239		int ecp_div = 0;
240
241		while (ecp > par->pll_limits.ecp_max && ecp_div < 2) {
242			ecp >>= 1;
243			ecp_div++;
244		}
245		pll->pll_vclk_cntl |= ecp_div << 4;
246	}
247
248	return 0;
249}
250
251static int aty_var_to_pll_ct(const struct fb_info *info, u32 vclk_per, u32 bpp, union aty_pll *pll)
252{
253	struct atyfb_par *par = (struct atyfb_par *) info->par;
254	int err;
255
256	if ((err = aty_valid_pll_ct(info, vclk_per, &pll->ct)))
257		return err;
258	if (M64_HAS(GTB_DSP) && (err = aty_dsp_gt(info, bpp, &pll->ct)))
259		return err;
260	/*aty_calc_pll_ct(info, &pll->ct);*/
261	return 0;
262}
263
264static u32 aty_pll_to_var_ct(const struct fb_info *info, const union aty_pll *pll)
265{
266	struct atyfb_par *par = (struct atyfb_par *) info->par;
267	u32 ret;
268	ret = par->ref_clk_per * pll->ct.pll_ref_div * pll->ct.vclk_post_div_real / pll->ct.vclk_fb_div / 2;
269#ifdef CONFIG_FB_ATY_GENERIC_LCD
270	if(pll->ct.xres > 0) {
271		ret *= par->lcd_width;
272		ret /= pll->ct.xres;
273	}
274#endif
275#ifdef DEBUG
276	printk("atyfb(%s): calculated 0x%08X(%i)\n", __func__, ret, ret);
277#endif
278	return ret;
279}
280
281void aty_set_pll_ct(const struct fb_info *info, const union aty_pll *pll)
282{
283	struct atyfb_par *par = (struct atyfb_par *) info->par;
284	u32 crtc_gen_cntl, lcd_gen_cntrl;
285	u8 tmp, tmp2;
286
287	lcd_gen_cntrl = 0;
288#ifdef DEBUG
289	printk("atyfb(%s): about to program:\n"
290		"pll_ext_cntl=0x%02x pll_gen_cntl=0x%02x pll_vclk_cntl=0x%02x\n",
291		__func__,
292		pll->ct.pll_ext_cntl, pll->ct.pll_gen_cntl, pll->ct.pll_vclk_cntl);
293
294	printk("atyfb(%s): setting clock %lu for FeedBackDivider %i, ReferenceDivider %i, PostDivider %i(%i)\n",
295		__func__,
296		par->clk_wr_offset, pll->ct.vclk_fb_div,
297		pll->ct.pll_ref_div, pll->ct.vclk_post_div, pll->ct.vclk_post_div_real);
298#endif
299#ifdef CONFIG_FB_ATY_GENERIC_LCD
300	if (par->lcd_table != 0) {
301		/* turn off LCD */
302		lcd_gen_cntrl = aty_ld_lcd(LCD_GEN_CNTL, par);
303		aty_st_lcd(LCD_GEN_CNTL, lcd_gen_cntrl & ~LCD_ON, par);
304	}
305#endif
306	aty_st_8(CLOCK_CNTL, par->clk_wr_offset | CLOCK_STROBE, par);
307
308	/* Temporarily switch to accelerator mode */
309	crtc_gen_cntl = aty_ld_le32(CRTC_GEN_CNTL, par);
310	if (!(crtc_gen_cntl & CRTC_EXT_DISP_EN))
311		aty_st_le32(CRTC_GEN_CNTL, crtc_gen_cntl | CRTC_EXT_DISP_EN, par);
312
313	/* Reset VCLK generator */
314	aty_st_pll_ct(PLL_VCLK_CNTL, pll->ct.pll_vclk_cntl, par);
315
316	/* Set post-divider */
317	tmp2 = par->clk_wr_offset << 1;
318	tmp = aty_ld_pll_ct(VCLK_POST_DIV, par);
319	tmp &= ~(0x03U << tmp2);
320	tmp |= ((pll->ct.vclk_post_div & 0x03U) << tmp2);
321	aty_st_pll_ct(VCLK_POST_DIV, tmp, par);
322
323	/* Set extended post-divider */
324	tmp = aty_ld_pll_ct(PLL_EXT_CNTL, par);
325	tmp &= ~(0x10U << par->clk_wr_offset);
326	tmp &= 0xF0U;
327	tmp |= pll->ct.pll_ext_cntl;
328	aty_st_pll_ct(PLL_EXT_CNTL, tmp, par);
329
330	/* Set feedback divider */
331	tmp = VCLK0_FB_DIV + par->clk_wr_offset;
332	aty_st_pll_ct(tmp, (pll->ct.vclk_fb_div & 0xFFU), par);
333
334	aty_st_pll_ct(PLL_GEN_CNTL, (pll->ct.pll_gen_cntl & (~(PLL_OVERRIDE | PLL_MCLK_RST))) | OSC_EN, par);
335
336	/* End VCLK generator reset */
337	aty_st_pll_ct(PLL_VCLK_CNTL, pll->ct.pll_vclk_cntl & ~(PLL_VCLK_RST), par);
338	mdelay(5);
339
340	aty_st_pll_ct(PLL_GEN_CNTL, pll->ct.pll_gen_cntl, par);
341	aty_st_pll_ct(PLL_VCLK_CNTL, pll->ct.pll_vclk_cntl, par);
342	mdelay(1);
343
344	/* Restore mode register */
345	if (!(crtc_gen_cntl & CRTC_EXT_DISP_EN))
346		aty_st_le32(CRTC_GEN_CNTL, crtc_gen_cntl, par);
347
348	if (M64_HAS(GTB_DSP)) {
349		u8 dll_cntl;
350
351		if (M64_HAS(XL_DLL))
352			dll_cntl = 0x80;
353		else if (par->ram_type >= SDRAM)
354			dll_cntl = 0xa6;
355		else
356			dll_cntl = 0xa0;
357		aty_st_pll_ct(DLL_CNTL, dll_cntl, par);
358		aty_st_pll_ct(VFC_CNTL, 0x1b, par);
359		aty_st_le32(DSP_CONFIG, pll->ct.dsp_config, par);
360		aty_st_le32(DSP_ON_OFF, pll->ct.dsp_on_off, par);
361
362		mdelay(10);
363		aty_st_pll_ct(DLL_CNTL, dll_cntl, par);
364		mdelay(10);
365		aty_st_pll_ct(DLL_CNTL, dll_cntl | 0x40, par);
366		mdelay(10);
367		aty_st_pll_ct(DLL_CNTL, dll_cntl & ~0x40, par);
368	}
369#ifdef CONFIG_FB_ATY_GENERIC_LCD
370	if (par->lcd_table != 0) {
371		/* restore LCD */
372		aty_st_lcd(LCD_GEN_CNTL, lcd_gen_cntrl, par);
373	}
374#endif
375}
376
377static void aty_get_pll_ct(const struct fb_info *info, union aty_pll *pll)
378{
379	struct atyfb_par *par = (struct atyfb_par *) info->par;
380	u8 tmp, clock;
381
382	clock = aty_ld_8(CLOCK_CNTL, par) & 0x03U;
383	tmp = clock << 1;
384	pll->ct.vclk_post_div = (aty_ld_pll_ct(VCLK_POST_DIV, par) >> tmp) & 0x03U;
385
386	pll->ct.pll_ext_cntl = aty_ld_pll_ct(PLL_EXT_CNTL, par) & 0x0FU;
387	pll->ct.vclk_fb_div = aty_ld_pll_ct(VCLK0_FB_DIV + clock, par) & 0xFFU;
388	pll->ct.pll_ref_div = aty_ld_pll_ct(PLL_REF_DIV, par);
389	pll->ct.mclk_fb_div = aty_ld_pll_ct(MCLK_FB_DIV, par);
390
391	pll->ct.pll_gen_cntl = aty_ld_pll_ct(PLL_GEN_CNTL, par);
392	pll->ct.pll_vclk_cntl = aty_ld_pll_ct(PLL_VCLK_CNTL, par);
393
394	if (M64_HAS(GTB_DSP)) {
395		pll->ct.dsp_config = aty_ld_le32(DSP_CONFIG, par);
396		pll->ct.dsp_on_off = aty_ld_le32(DSP_ON_OFF, par);
397	}
398}
399
400static int aty_init_pll_ct(const struct fb_info *info, union aty_pll *pll)
401{
402	struct atyfb_par *par = (struct atyfb_par *) info->par;
403	u8 mpost_div, xpost_div, sclk_post_div_real;
404	u32 q, memcntl, trp;
405	u32 dsp_config, dsp_on_off, vga_dsp_config, vga_dsp_on_off;
406#ifdef DEBUG
407	int pllmclk, pllsclk;
408#endif
409	pll->ct.pll_ext_cntl = aty_ld_pll_ct(PLL_EXT_CNTL, par);
410	pll->ct.xclk_post_div = pll->ct.pll_ext_cntl & 0x07;
411	pll->ct.xclk_ref_div = 1;
412	switch (pll->ct.xclk_post_div) {
413	case 0:  case 1:  case 2:  case 3:
414		break;
415
416	case 4:
417		pll->ct.xclk_ref_div = 3;
418		pll->ct.xclk_post_div = 0;
419		break;
420
421	default:
422		printk(KERN_CRIT "atyfb: Unsupported xclk source:  %d.\n", pll->ct.xclk_post_div);
423		return -EINVAL;
424	}
425	pll->ct.mclk_fb_mult = 2;
426	if(pll->ct.pll_ext_cntl & PLL_MFB_TIMES_4_2B) {
427		pll->ct.mclk_fb_mult = 4;
428		pll->ct.xclk_post_div -= 1;
429	}
430
431#ifdef DEBUG
432	printk("atyfb(%s): mclk_fb_mult=%d, xclk_post_div=%d\n",
433		__func__, pll->ct.mclk_fb_mult, pll->ct.xclk_post_div);
434#endif
435
436	memcntl = aty_ld_le32(MEM_CNTL, par);
437	trp = (memcntl & 0x300) >> 8;
438
439	pll->ct.xclkpagefaultdelay = ((memcntl & 0xc00) >> 10) + ((memcntl & 0x1000) >> 12) + trp + 2;
440	pll->ct.xclkmaxrasdelay = ((memcntl & 0x70000) >> 16) + trp + 2;
441
442	if (M64_HAS(FIFO_32)) {
443		pll->ct.fifo_size = 32;
444	} else {
445		pll->ct.fifo_size = 24;
446		pll->ct.xclkpagefaultdelay += 2;
447		pll->ct.xclkmaxrasdelay += 3;
448	}
449
450	switch (par->ram_type) {
451	case DRAM:
452		if (info->fix.smem_len<=ONE_MB) {
453			pll->ct.dsp_loop_latency = 10;
454		} else {
455			pll->ct.dsp_loop_latency = 8;
456			pll->ct.xclkpagefaultdelay += 2;
457		}
458		break;
459	case EDO:
460	case PSEUDO_EDO:
461		if (info->fix.smem_len<=ONE_MB) {
462			pll->ct.dsp_loop_latency = 9;
463		} else {
464			pll->ct.dsp_loop_latency = 8;
465			pll->ct.xclkpagefaultdelay += 1;
466		}
467		break;
468	case SDRAM:
469		if (info->fix.smem_len<=ONE_MB) {
470			pll->ct.dsp_loop_latency = 11;
471		} else {
472			pll->ct.dsp_loop_latency = 10;
473			pll->ct.xclkpagefaultdelay += 1;
474		}
475		break;
476	case SGRAM:
477		pll->ct.dsp_loop_latency = 8;
478		pll->ct.xclkpagefaultdelay += 3;
479		break;
480	default:
481		pll->ct.dsp_loop_latency = 11;
482		pll->ct.xclkpagefaultdelay += 3;
483		break;
484	}
485
486	if (pll->ct.xclkmaxrasdelay <= pll->ct.xclkpagefaultdelay)
487		pll->ct.xclkmaxrasdelay = pll->ct.xclkpagefaultdelay + 1;
488
489	/* Allow BIOS to override */
490	dsp_config = aty_ld_le32(DSP_CONFIG, par);
491	dsp_on_off = aty_ld_le32(DSP_ON_OFF, par);
492	vga_dsp_config = aty_ld_le32(VGA_DSP_CONFIG, par);
493	vga_dsp_on_off = aty_ld_le32(VGA_DSP_ON_OFF, par);
494
495	if (dsp_config)
496		pll->ct.dsp_loop_latency = (dsp_config & DSP_LOOP_LATENCY) >> 16;
497#if 0
498	FIXME: is it relevant for us?
499	if ((!dsp_on_off && !M64_HAS(RESET_3D)) ||
500		((dsp_on_off == vga_dsp_on_off) &&
501		(!dsp_config || !((dsp_config ^ vga_dsp_config) & DSP_XCLKS_PER_QW)))) {
502		vga_dsp_on_off &= VGA_DSP_OFF;
503		vga_dsp_config &= VGA_DSP_XCLKS_PER_QW;
504		if (ATIDivide(vga_dsp_on_off, vga_dsp_config, 5, 1) > 24)
505			pll->ct.fifo_size = 32;
506		else
507			pll->ct.fifo_size = 24;
508	}
509#endif
510	/* Exit if the user does not want us to tamper with the clock
511	rates of her chip. */
512	if (par->mclk_per == 0) {
513		u8 mclk_fb_div, pll_ext_cntl;
514		pll->ct.pll_ref_div = aty_ld_pll_ct(PLL_REF_DIV, par);
515		pll_ext_cntl = aty_ld_pll_ct(PLL_EXT_CNTL, par);
516		pll->ct.xclk_post_div_real = aty_postdividers[pll_ext_cntl & 0x07];
517		mclk_fb_div = aty_ld_pll_ct(MCLK_FB_DIV, par);
518		if (pll_ext_cntl & PLL_MFB_TIMES_4_2B)
519			mclk_fb_div <<= 1;
520		pll->ct.mclk_fb_div = mclk_fb_div;
521		return 0;
522	}
523
524	pll->ct.pll_ref_div = par->pll_per * 2 * 255 / par->ref_clk_per;
525
526	/* FIXME: use the VTB/GTB /3 post divider if it's better suited */
527	q = par->ref_clk_per * pll->ct.pll_ref_div * 8 /
528		(pll->ct.mclk_fb_mult * par->xclk_per);
529
530	if (q < 16*8 || q > 255*8) {
531		printk(KERN_CRIT "atxfb: xclk out of range\n");
532		return -EINVAL;
533	} else {
534		xpost_div  = (q < 128*8);
535		xpost_div += (q <  64*8);
536		xpost_div += (q <  32*8);
537	}
538	pll->ct.xclk_post_div_real = aty_postdividers[xpost_div];
539	pll->ct.mclk_fb_div = q * pll->ct.xclk_post_div_real / 8;
540
541#ifdef CONFIG_PPC
542	if (machine_is(powermac)) {
543		/* Override PLL_EXT_CNTL & 0x07. */
544		pll->ct.xclk_post_div = xpost_div;
545		pll->ct.xclk_ref_div = 1;
546	}
547#endif
548
549#ifdef DEBUG
550	pllmclk = (1000000 * pll->ct.mclk_fb_mult * pll->ct.mclk_fb_div) /
551			(par->ref_clk_per * pll->ct.pll_ref_div);
552	printk("atyfb(%s): pllmclk=%d MHz, xclk=%d MHz\n",
553		__func__, pllmclk, pllmclk / pll->ct.xclk_post_div_real);
554#endif
555
556	if (M64_HAS(SDRAM_MAGIC_PLL) && (par->ram_type >= SDRAM))
557		pll->ct.pll_gen_cntl = OSC_EN;
558	else
559		pll->ct.pll_gen_cntl = OSC_EN | DLL_PWDN /* | FORCE_DCLK_TRI_STATE */;
560
561	if (M64_HAS(MAGIC_POSTDIV))
562		pll->ct.pll_ext_cntl = 0;
563	else
564		pll->ct.pll_ext_cntl = xpost_div;
565
566	if (pll->ct.mclk_fb_mult == 4)
567		pll->ct.pll_ext_cntl |= PLL_MFB_TIMES_4_2B;
568
569	if (par->mclk_per == par->xclk_per) {
570		pll->ct.pll_gen_cntl |= (xpost_div << 4); /* mclk == xclk */
571	} else {
572		/*
573		* The chip clock is not equal to the memory clock.
574		* Therefore we will use sclk to clock the chip.
575		*/
576		pll->ct.pll_gen_cntl |= (6 << 4); /* mclk == sclk */
577
578		q = par->ref_clk_per * pll->ct.pll_ref_div * 4 / par->mclk_per;
579		if (q < 16*8 || q > 255*8) {
580			printk(KERN_CRIT "atyfb: mclk out of range\n");
581			return -EINVAL;
582		} else {
583			mpost_div  = (q < 128*8);
584			mpost_div += (q <  64*8);
585			mpost_div += (q <  32*8);
586		}
587		sclk_post_div_real = aty_postdividers[mpost_div];
588		pll->ct.sclk_fb_div = q * sclk_post_div_real / 8;
589		pll->ct.spll_cntl2 = mpost_div << 4;
590#ifdef DEBUG
591		pllsclk = (1000000 * 2 * pll->ct.sclk_fb_div) /
592			(par->ref_clk_per * pll->ct.pll_ref_div);
593		printk("atyfb(%s): use sclk, pllsclk=%d MHz, sclk=mclk=%d MHz\n",
594			__func__, pllsclk, pllsclk / sclk_post_div_real);
595#endif
596	}
597
598	/* Disable the extra precision pixel clock controls since we do not use them. */
599	pll->ct.ext_vpll_cntl = aty_ld_pll_ct(EXT_VPLL_CNTL, par);
600	pll->ct.ext_vpll_cntl &= ~(EXT_VPLL_EN | EXT_VPLL_VGA_EN | EXT_VPLL_INSYNC);
601
602	return 0;
603}
604
605static void aty_resume_pll_ct(const struct fb_info *info,
606			      union aty_pll *pll)
607{
608	struct atyfb_par *par = info->par;
609
610	if (par->mclk_per != par->xclk_per) {
611		/*
612		* This disables the sclk, crashes the computer as reported:
613		* aty_st_pll_ct(SPLL_CNTL2, 3, info);
614		*
615		* So it seems the sclk must be enabled before it is used;
616		* so PLL_GEN_CNTL must be programmed *after* the sclk.
617		*/
618		aty_st_pll_ct(SCLK_FB_DIV, pll->ct.sclk_fb_div, par);
619		aty_st_pll_ct(SPLL_CNTL2, pll->ct.spll_cntl2, par);
620		/*
621		 * SCLK has been started. Wait for the PLL to lock. 5 ms
622		 * should be enough according to mach64 programmer's guide.
623		 */
624		mdelay(5);
625	}
626
627	aty_st_pll_ct(PLL_REF_DIV, pll->ct.pll_ref_div, par);
628	aty_st_pll_ct(PLL_GEN_CNTL, pll->ct.pll_gen_cntl, par);
629	aty_st_pll_ct(MCLK_FB_DIV, pll->ct.mclk_fb_div, par);
630	aty_st_pll_ct(PLL_EXT_CNTL, pll->ct.pll_ext_cntl, par);
631	aty_st_pll_ct(EXT_VPLL_CNTL, pll->ct.ext_vpll_cntl, par);
632}
633
634static int dummy(void)
635{
636	return 0;
637}
638
639const struct aty_dac_ops aty_dac_ct = {
640	.set_dac	= (void *) dummy,
641};
642
643const struct aty_pll_ops aty_pll_ct = {
644	.var_to_pll	= aty_var_to_pll_ct,
645	.pll_to_var	= aty_pll_to_var_ct,
646	.set_pll	= aty_set_pll_ct,
647	.get_pll	= aty_get_pll_ct,
648	.init_pll	= aty_init_pll_ct,
649	.resume_pll	= aty_resume_pll_ct,
650};
651