xref: /openbmc/linux/arch/mips/alchemy/common/clock.c (revision e58e871b)
1 /*
2  * Alchemy clocks.
3  *
4  * Exposes all configurable internal clock sources to the clk framework.
5  *
6  * We have:
7  *  - Root source, usually 12MHz supplied by an external crystal
8  *  - 3 PLLs which generate multiples of root rate [AUX, CPU, AUX2]
9  *
10  * Dividers:
11  *  - 6 clock dividers with:
12  *   * selectable source [one of the PLLs],
13  *   * output divided between [2 .. 512 in steps of 2] (!Au1300)
14  *     or [1 .. 256 in steps of 1] (Au1300),
15  *   * can be enabled individually.
16  *
17  * - up to 6 "internal" (fixed) consumers which:
18  *   * take either AUXPLL or one of the above 6 dividers as input,
19  *   * divide this input by 1, 2, or 4 (and 3 on Au1300).
20  *   * can be disabled separately.
21  *
22  * Misc clocks:
23  * - sysbus clock: CPU core clock (CPUPLL) divided by 2, 3 or 4.
24  *    depends on board design and should be set by bootloader, read-only.
25  * - peripheral clock: half the rate of sysbus clock, source for a lot
26  *    of peripheral blocks, read-only.
27  * - memory clock: clk rate to main memory chips, depends on board
28  *    design and is read-only,
29  * - lrclk: the static bus clock signal for synchronous operation.
30  *    depends on board design, must be set by bootloader,
31  *    but may be required to correctly configure devices attached to
32  *    the static bus. The Au1000/1500/1100 manuals call it LCLK, on
33  *    later models it's called RCLK.
34  */
35 
36 #include <linux/init.h>
37 #include <linux/io.h>
38 #include <linux/clk.h>
39 #include <linux/clk-provider.h>
40 #include <linux/clkdev.h>
41 #include <linux/slab.h>
42 #include <linux/spinlock.h>
43 #include <linux/types.h>
44 #include <asm/mach-au1x00/au1000.h>
45 
46 /* Base clock: 12MHz is the default in all databooks, and I haven't
47  * found any board yet which uses a different rate.
48  */
49 #define ALCHEMY_ROOTCLK_RATE	12000000
50 
51 /*
52  * the internal sources which can be driven by the PLLs and dividers.
53  * Names taken from the databooks, refer to them for more information,
54  * especially which ones are share a clock line.
55  */
56 static const char * const alchemy_au1300_intclknames[] = {
57 	"lcd_intclk", "gpemgp_clk", "maempe_clk", "maebsa_clk",
58 	"EXTCLK0", "EXTCLK1"
59 };
60 
61 static const char * const alchemy_au1200_intclknames[] = {
62 	"lcd_intclk", NULL, NULL, NULL, "EXTCLK0", "EXTCLK1"
63 };
64 
65 static const char * const alchemy_au1550_intclknames[] = {
66 	"usb_clk", "psc0_intclk", "psc1_intclk", "pci_clko",
67 	"EXTCLK0", "EXTCLK1"
68 };
69 
70 static const char * const alchemy_au1100_intclknames[] = {
71 	"usb_clk", "lcd_intclk", NULL, "i2s_clk", "EXTCLK0", "EXTCLK1"
72 };
73 
74 static const char * const alchemy_au1500_intclknames[] = {
75 	NULL, "usbd_clk", "usbh_clk", "pci_clko", "EXTCLK0", "EXTCLK1"
76 };
77 
78 static const char * const alchemy_au1000_intclknames[] = {
79 	"irda_clk", "usbd_clk", "usbh_clk", "i2s_clk", "EXTCLK0",
80 	"EXTCLK1"
81 };
82 
83 /* aliases for a few on-chip sources which are either shared
84  * or have gone through name changes.
85  */
86 static struct clk_aliastable {
87 	char *alias;
88 	char *base;
89 	int cputype;
90 } alchemy_clk_aliases[] __initdata = {
91 	{ "usbh_clk", "usb_clk",    ALCHEMY_CPU_AU1100 },
92 	{ "usbd_clk", "usb_clk",    ALCHEMY_CPU_AU1100 },
93 	{ "irda_clk", "usb_clk",    ALCHEMY_CPU_AU1100 },
94 	{ "usbh_clk", "usb_clk",    ALCHEMY_CPU_AU1550 },
95 	{ "usbd_clk", "usb_clk",    ALCHEMY_CPU_AU1550 },
96 	{ "psc2_intclk", "usb_clk", ALCHEMY_CPU_AU1550 },
97 	{ "psc3_intclk", "EXTCLK0", ALCHEMY_CPU_AU1550 },
98 	{ "psc0_intclk", "EXTCLK0", ALCHEMY_CPU_AU1200 },
99 	{ "psc1_intclk", "EXTCLK1", ALCHEMY_CPU_AU1200 },
100 	{ "psc0_intclk", "EXTCLK0", ALCHEMY_CPU_AU1300 },
101 	{ "psc2_intclk", "EXTCLK0", ALCHEMY_CPU_AU1300 },
102 	{ "psc1_intclk", "EXTCLK1", ALCHEMY_CPU_AU1300 },
103 	{ "psc3_intclk", "EXTCLK1", ALCHEMY_CPU_AU1300 },
104 
105 	{ NULL, NULL, 0 },
106 };
107 
108 #define IOMEM(x)	((void __iomem *)(KSEG1ADDR(CPHYSADDR(x))))
109 
110 /* access locks to SYS_FREQCTRL0/1 and SYS_CLKSRC registers */
111 static spinlock_t alchemy_clk_fg0_lock;
112 static spinlock_t alchemy_clk_fg1_lock;
113 static spinlock_t alchemy_clk_csrc_lock;
114 
115 /* CPU Core clock *****************************************************/
116 
117 static unsigned long alchemy_clk_cpu_recalc(struct clk_hw *hw,
118 					    unsigned long parent_rate)
119 {
120 	unsigned long t;
121 
122 	/*
123 	 * On early Au1000, sys_cpupll was write-only. Since these
124 	 * silicon versions of Au1000 are not sold, we don't bend
125 	 * over backwards trying to determine the frequency.
126 	 */
127 	if (unlikely(au1xxx_cpu_has_pll_wo()))
128 		t = 396000000;
129 	else {
130 		t = alchemy_rdsys(AU1000_SYS_CPUPLL) & 0x7f;
131 		if (alchemy_get_cputype() < ALCHEMY_CPU_AU1300)
132 			t &= 0x3f;
133 		t *= parent_rate;
134 	}
135 
136 	return t;
137 }
138 
139 void __init alchemy_set_lpj(void)
140 {
141 	preset_lpj = alchemy_clk_cpu_recalc(NULL, ALCHEMY_ROOTCLK_RATE);
142 	preset_lpj /= 2 * HZ;
143 }
144 
145 static struct clk_ops alchemy_clkops_cpu = {
146 	.recalc_rate	= alchemy_clk_cpu_recalc,
147 };
148 
149 static struct clk __init *alchemy_clk_setup_cpu(const char *parent_name,
150 						int ctype)
151 {
152 	struct clk_init_data id;
153 	struct clk_hw *h;
154 
155 	h = kzalloc(sizeof(*h), GFP_KERNEL);
156 	if (!h)
157 		return ERR_PTR(-ENOMEM);
158 
159 	id.name = ALCHEMY_CPU_CLK;
160 	id.parent_names = &parent_name;
161 	id.num_parents = 1;
162 	id.flags = CLK_IS_BASIC;
163 	id.ops = &alchemy_clkops_cpu;
164 	h->init = &id;
165 
166 	return clk_register(NULL, h);
167 }
168 
169 /* AUXPLLs ************************************************************/
170 
171 struct alchemy_auxpll_clk {
172 	struct clk_hw hw;
173 	unsigned long reg;	/* au1300 has also AUXPLL2 */
174 	int maxmult;		/* max multiplier */
175 };
176 #define to_auxpll_clk(x) container_of(x, struct alchemy_auxpll_clk, hw)
177 
178 static unsigned long alchemy_clk_aux_recalc(struct clk_hw *hw,
179 					    unsigned long parent_rate)
180 {
181 	struct alchemy_auxpll_clk *a = to_auxpll_clk(hw);
182 
183 	return (alchemy_rdsys(a->reg) & 0xff) * parent_rate;
184 }
185 
186 static int alchemy_clk_aux_setr(struct clk_hw *hw,
187 				unsigned long rate,
188 				unsigned long parent_rate)
189 {
190 	struct alchemy_auxpll_clk *a = to_auxpll_clk(hw);
191 	unsigned long d = rate;
192 
193 	if (rate)
194 		d /= parent_rate;
195 	else
196 		d = 0;
197 
198 	/* minimum is 84MHz, max is 756-1032 depending on variant */
199 	if (((d < 7) && (d != 0)) || (d > a->maxmult))
200 		return -EINVAL;
201 
202 	alchemy_wrsys(d, a->reg);
203 	return 0;
204 }
205 
206 static long alchemy_clk_aux_roundr(struct clk_hw *hw,
207 					    unsigned long rate,
208 					    unsigned long *parent_rate)
209 {
210 	struct alchemy_auxpll_clk *a = to_auxpll_clk(hw);
211 	unsigned long mult;
212 
213 	if (!rate || !*parent_rate)
214 		return 0;
215 
216 	mult = rate / (*parent_rate);
217 
218 	if (mult && (mult < 7))
219 		mult = 7;
220 	if (mult > a->maxmult)
221 		mult = a->maxmult;
222 
223 	return (*parent_rate) * mult;
224 }
225 
226 static struct clk_ops alchemy_clkops_aux = {
227 	.recalc_rate	= alchemy_clk_aux_recalc,
228 	.set_rate	= alchemy_clk_aux_setr,
229 	.round_rate	= alchemy_clk_aux_roundr,
230 };
231 
232 static struct clk __init *alchemy_clk_setup_aux(const char *parent_name,
233 						char *name, int maxmult,
234 						unsigned long reg)
235 {
236 	struct clk_init_data id;
237 	struct clk *c;
238 	struct alchemy_auxpll_clk *a;
239 
240 	a = kzalloc(sizeof(*a), GFP_KERNEL);
241 	if (!a)
242 		return ERR_PTR(-ENOMEM);
243 
244 	id.name = name;
245 	id.parent_names = &parent_name;
246 	id.num_parents = 1;
247 	id.flags = CLK_GET_RATE_NOCACHE;
248 	id.ops = &alchemy_clkops_aux;
249 
250 	a->reg = reg;
251 	a->maxmult = maxmult;
252 	a->hw.init = &id;
253 
254 	c = clk_register(NULL, &a->hw);
255 	if (!IS_ERR(c))
256 		clk_register_clkdev(c, name, NULL);
257 	else
258 		kfree(a);
259 
260 	return c;
261 }
262 
263 /* sysbus_clk *********************************************************/
264 
265 static struct clk __init  *alchemy_clk_setup_sysbus(const char *pn)
266 {
267 	unsigned long v = (alchemy_rdsys(AU1000_SYS_POWERCTRL) & 3) + 2;
268 	struct clk *c;
269 
270 	c = clk_register_fixed_factor(NULL, ALCHEMY_SYSBUS_CLK,
271 				      pn, 0, 1, v);
272 	if (!IS_ERR(c))
273 		clk_register_clkdev(c, ALCHEMY_SYSBUS_CLK, NULL);
274 	return c;
275 }
276 
277 /* Peripheral Clock ***************************************************/
278 
279 static struct clk __init *alchemy_clk_setup_periph(const char *pn)
280 {
281 	/* Peripheral clock runs at half the rate of sysbus clk */
282 	struct clk *c;
283 
284 	c = clk_register_fixed_factor(NULL, ALCHEMY_PERIPH_CLK,
285 				      pn, 0, 1, 2);
286 	if (!IS_ERR(c))
287 		clk_register_clkdev(c, ALCHEMY_PERIPH_CLK, NULL);
288 	return c;
289 }
290 
291 /* mem clock **********************************************************/
292 
293 static struct clk __init *alchemy_clk_setup_mem(const char *pn, int ct)
294 {
295 	void __iomem *addr = IOMEM(AU1000_MEM_PHYS_ADDR);
296 	unsigned long v;
297 	struct clk *c;
298 	int div;
299 
300 	switch (ct) {
301 	case ALCHEMY_CPU_AU1550:
302 	case ALCHEMY_CPU_AU1200:
303 		v = __raw_readl(addr + AU1550_MEM_SDCONFIGB);
304 		div = (v & (1 << 15)) ? 1 : 2;
305 		break;
306 	case ALCHEMY_CPU_AU1300:
307 		v = __raw_readl(addr + AU1550_MEM_SDCONFIGB);
308 		div = (v & (1 << 31)) ? 1 : 2;
309 		break;
310 	case ALCHEMY_CPU_AU1000:
311 	case ALCHEMY_CPU_AU1500:
312 	case ALCHEMY_CPU_AU1100:
313 	default:
314 		div = 2;
315 		break;
316 	}
317 
318 	c = clk_register_fixed_factor(NULL, ALCHEMY_MEM_CLK, pn,
319 				      0, 1, div);
320 	if (!IS_ERR(c))
321 		clk_register_clkdev(c, ALCHEMY_MEM_CLK, NULL);
322 	return c;
323 }
324 
325 /* lrclk: external synchronous static bus clock ***********************/
326 
327 static struct clk __init *alchemy_clk_setup_lrclk(const char *pn, int t)
328 {
329 	/* Au1000, Au1500: MEM_STCFG0[11]: If bit is set, lrclk=pclk/5,
330 	 * otherwise lrclk=pclk/4.
331 	 * All other variants: MEM_STCFG0[15:13] = divisor.
332 	 * L/RCLK = periph_clk / (divisor + 1)
333 	 * On Au1000, Au1500, Au1100 it's called LCLK,
334 	 * on later models it's called RCLK, but it's the same thing.
335 	 */
336 	struct clk *c;
337 	unsigned long v = alchemy_rdsmem(AU1000_MEM_STCFG0);
338 
339 	switch (t) {
340 	case ALCHEMY_CPU_AU1000:
341 	case ALCHEMY_CPU_AU1500:
342 		v = 4 + ((v >> 11) & 1);
343 		break;
344 	default:	/* all other models */
345 		v = ((v >> 13) & 7) + 1;
346 	}
347 	c = clk_register_fixed_factor(NULL, ALCHEMY_LR_CLK,
348 				      pn, 0, 1, v);
349 	if (!IS_ERR(c))
350 		clk_register_clkdev(c, ALCHEMY_LR_CLK, NULL);
351 	return c;
352 }
353 
354 /* Clock dividers and muxes *******************************************/
355 
356 /* data for fgen and csrc mux-dividers */
357 struct alchemy_fgcs_clk {
358 	struct clk_hw hw;
359 	spinlock_t *reglock;	/* register lock		  */
360 	unsigned long reg;	/* SYS_FREQCTRL0/1		  */
361 	int shift;		/* offset in register		  */
362 	int parent;		/* parent before disable [Au1300] */
363 	int isen;		/* is it enabled?		  */
364 	int *dt;		/* dividertable for csrc	  */
365 };
366 #define to_fgcs_clk(x) container_of(x, struct alchemy_fgcs_clk, hw)
367 
368 static long alchemy_calc_div(unsigned long rate, unsigned long prate,
369 			       int scale, int maxdiv, unsigned long *rv)
370 {
371 	long div1, div2;
372 
373 	div1 = prate / rate;
374 	if ((prate / div1) > rate)
375 		div1++;
376 
377 	if (scale == 2) {	/* only div-by-multiple-of-2 possible */
378 		if (div1 & 1)
379 			div1++;	/* stay <=prate */
380 	}
381 
382 	div2 = (div1 / scale) - 1;	/* value to write to register */
383 
384 	if (div2 > maxdiv)
385 		div2 = maxdiv;
386 	if (rv)
387 		*rv = div2;
388 
389 	div1 = ((div2 + 1) * scale);
390 	return div1;
391 }
392 
393 static int alchemy_clk_fgcs_detr(struct clk_hw *hw,
394 				 struct clk_rate_request *req,
395 				 int scale, int maxdiv)
396 {
397 	struct clk_hw *pc, *bpc, *free;
398 	long tdv, tpr, pr, nr, br, bpr, diff, lastdiff;
399 	int j;
400 
401 	lastdiff = INT_MAX;
402 	bpr = 0;
403 	bpc = NULL;
404 	br = -EINVAL;
405 	free = NULL;
406 
407 	/* look at the rates each enabled parent supplies and select
408 	 * the one that gets closest to but not over the requested rate.
409 	 */
410 	for (j = 0; j < 7; j++) {
411 		pc = clk_hw_get_parent_by_index(hw, j);
412 		if (!pc)
413 			break;
414 
415 		/* if this parent is currently unused, remember it.
416 		 * XXX: we would actually want clk_has_active_children()
417 		 * but this is a good-enough approximation for now.
418 		 */
419 		if (!clk_hw_is_prepared(pc)) {
420 			if (!free)
421 				free = pc;
422 		}
423 
424 		pr = clk_hw_get_rate(pc);
425 		if (pr < req->rate)
426 			continue;
427 
428 		/* what can hardware actually provide */
429 		tdv = alchemy_calc_div(req->rate, pr, scale, maxdiv, NULL);
430 		nr = pr / tdv;
431 		diff = req->rate - nr;
432 		if (nr > req->rate)
433 			continue;
434 
435 		if (diff < lastdiff) {
436 			lastdiff = diff;
437 			bpr = pr;
438 			bpc = pc;
439 			br = nr;
440 		}
441 		if (diff == 0)
442 			break;
443 	}
444 
445 	/* if we couldn't get the exact rate we wanted from the enabled
446 	 * parents, maybe we can tell an available disabled/inactive one
447 	 * to give us a rate we can divide down to the requested rate.
448 	 */
449 	if (lastdiff && free) {
450 		for (j = (maxdiv == 4) ? 1 : scale; j <= maxdiv; j += scale) {
451 			tpr = req->rate * j;
452 			if (tpr < 0)
453 				break;
454 			pr = clk_hw_round_rate(free, tpr);
455 
456 			tdv = alchemy_calc_div(req->rate, pr, scale, maxdiv,
457 					       NULL);
458 			nr = pr / tdv;
459 			diff = req->rate - nr;
460 			if (nr > req->rate)
461 				continue;
462 			if (diff < lastdiff) {
463 				lastdiff = diff;
464 				bpr = pr;
465 				bpc = free;
466 				br = nr;
467 			}
468 			if (diff == 0)
469 				break;
470 		}
471 	}
472 
473 	if (br < 0)
474 		return br;
475 
476 	req->best_parent_rate = bpr;
477 	req->best_parent_hw = bpc;
478 	req->rate = br;
479 
480 	return 0;
481 }
482 
483 static int alchemy_clk_fgv1_en(struct clk_hw *hw)
484 {
485 	struct alchemy_fgcs_clk *c = to_fgcs_clk(hw);
486 	unsigned long v, flags;
487 
488 	spin_lock_irqsave(c->reglock, flags);
489 	v = alchemy_rdsys(c->reg);
490 	v |= (1 << 1) << c->shift;
491 	alchemy_wrsys(v, c->reg);
492 	spin_unlock_irqrestore(c->reglock, flags);
493 
494 	return 0;
495 }
496 
497 static int alchemy_clk_fgv1_isen(struct clk_hw *hw)
498 {
499 	struct alchemy_fgcs_clk *c = to_fgcs_clk(hw);
500 	unsigned long v = alchemy_rdsys(c->reg) >> (c->shift + 1);
501 
502 	return v & 1;
503 }
504 
505 static void alchemy_clk_fgv1_dis(struct clk_hw *hw)
506 {
507 	struct alchemy_fgcs_clk *c = to_fgcs_clk(hw);
508 	unsigned long v, flags;
509 
510 	spin_lock_irqsave(c->reglock, flags);
511 	v = alchemy_rdsys(c->reg);
512 	v &= ~((1 << 1) << c->shift);
513 	alchemy_wrsys(v, c->reg);
514 	spin_unlock_irqrestore(c->reglock, flags);
515 }
516 
517 static int alchemy_clk_fgv1_setp(struct clk_hw *hw, u8 index)
518 {
519 	struct alchemy_fgcs_clk *c = to_fgcs_clk(hw);
520 	unsigned long v, flags;
521 
522 	spin_lock_irqsave(c->reglock, flags);
523 	v = alchemy_rdsys(c->reg);
524 	if (index)
525 		v |= (1 << c->shift);
526 	else
527 		v &= ~(1 << c->shift);
528 	alchemy_wrsys(v, c->reg);
529 	spin_unlock_irqrestore(c->reglock, flags);
530 
531 	return 0;
532 }
533 
534 static u8 alchemy_clk_fgv1_getp(struct clk_hw *hw)
535 {
536 	struct alchemy_fgcs_clk *c = to_fgcs_clk(hw);
537 
538 	return (alchemy_rdsys(c->reg) >> c->shift) & 1;
539 }
540 
541 static int alchemy_clk_fgv1_setr(struct clk_hw *hw, unsigned long rate,
542 				 unsigned long parent_rate)
543 {
544 	struct alchemy_fgcs_clk *c = to_fgcs_clk(hw);
545 	unsigned long div, v, flags, ret;
546 	int sh = c->shift + 2;
547 
548 	if (!rate || !parent_rate || rate > (parent_rate / 2))
549 		return -EINVAL;
550 	ret = alchemy_calc_div(rate, parent_rate, 2, 512, &div);
551 	spin_lock_irqsave(c->reglock, flags);
552 	v = alchemy_rdsys(c->reg);
553 	v &= ~(0xff << sh);
554 	v |= div << sh;
555 	alchemy_wrsys(v, c->reg);
556 	spin_unlock_irqrestore(c->reglock, flags);
557 
558 	return 0;
559 }
560 
561 static unsigned long alchemy_clk_fgv1_recalc(struct clk_hw *hw,
562 					     unsigned long parent_rate)
563 {
564 	struct alchemy_fgcs_clk *c = to_fgcs_clk(hw);
565 	unsigned long v = alchemy_rdsys(c->reg) >> (c->shift + 2);
566 
567 	v = ((v & 0xff) + 1) * 2;
568 	return parent_rate / v;
569 }
570 
571 static int alchemy_clk_fgv1_detr(struct clk_hw *hw,
572 				 struct clk_rate_request *req)
573 {
574 	return alchemy_clk_fgcs_detr(hw, req, 2, 512);
575 }
576 
577 /* Au1000, Au1100, Au15x0, Au12x0 */
578 static struct clk_ops alchemy_clkops_fgenv1 = {
579 	.recalc_rate	= alchemy_clk_fgv1_recalc,
580 	.determine_rate	= alchemy_clk_fgv1_detr,
581 	.set_rate	= alchemy_clk_fgv1_setr,
582 	.set_parent	= alchemy_clk_fgv1_setp,
583 	.get_parent	= alchemy_clk_fgv1_getp,
584 	.enable		= alchemy_clk_fgv1_en,
585 	.disable	= alchemy_clk_fgv1_dis,
586 	.is_enabled	= alchemy_clk_fgv1_isen,
587 };
588 
589 static void __alchemy_clk_fgv2_en(struct alchemy_fgcs_clk *c)
590 {
591 	unsigned long v = alchemy_rdsys(c->reg);
592 
593 	v &= ~(3 << c->shift);
594 	v |= (c->parent & 3) << c->shift;
595 	alchemy_wrsys(v, c->reg);
596 	c->isen = 1;
597 }
598 
599 static int alchemy_clk_fgv2_en(struct clk_hw *hw)
600 {
601 	struct alchemy_fgcs_clk *c = to_fgcs_clk(hw);
602 	unsigned long flags;
603 
604 	/* enable by setting the previous parent clock */
605 	spin_lock_irqsave(c->reglock, flags);
606 	__alchemy_clk_fgv2_en(c);
607 	spin_unlock_irqrestore(c->reglock, flags);
608 
609 	return 0;
610 }
611 
612 static int alchemy_clk_fgv2_isen(struct clk_hw *hw)
613 {
614 	struct alchemy_fgcs_clk *c = to_fgcs_clk(hw);
615 
616 	return ((alchemy_rdsys(c->reg) >> c->shift) & 3) != 0;
617 }
618 
619 static void alchemy_clk_fgv2_dis(struct clk_hw *hw)
620 {
621 	struct alchemy_fgcs_clk *c = to_fgcs_clk(hw);
622 	unsigned long v, flags;
623 
624 	spin_lock_irqsave(c->reglock, flags);
625 	v = alchemy_rdsys(c->reg);
626 	v &= ~(3 << c->shift);	/* set input mux to "disabled" state */
627 	alchemy_wrsys(v, c->reg);
628 	c->isen = 0;
629 	spin_unlock_irqrestore(c->reglock, flags);
630 }
631 
632 static int alchemy_clk_fgv2_setp(struct clk_hw *hw, u8 index)
633 {
634 	struct alchemy_fgcs_clk *c = to_fgcs_clk(hw);
635 	unsigned long flags;
636 
637 	spin_lock_irqsave(c->reglock, flags);
638 	c->parent = index + 1;	/* value to write to register */
639 	if (c->isen)
640 		__alchemy_clk_fgv2_en(c);
641 	spin_unlock_irqrestore(c->reglock, flags);
642 
643 	return 0;
644 }
645 
646 static u8 alchemy_clk_fgv2_getp(struct clk_hw *hw)
647 {
648 	struct alchemy_fgcs_clk *c = to_fgcs_clk(hw);
649 	unsigned long flags, v;
650 
651 	spin_lock_irqsave(c->reglock, flags);
652 	v = c->parent - 1;
653 	spin_unlock_irqrestore(c->reglock, flags);
654 	return v;
655 }
656 
657 /* fg0-2 and fg4-6 share a "scale"-bit. With this bit cleared, the
658  * dividers behave exactly as on previous models (dividers are multiples
659  * of 2); with the bit set, dividers are multiples of 1, halving their
660  * range, but making them also much more flexible.
661  */
662 static int alchemy_clk_fgv2_setr(struct clk_hw *hw, unsigned long rate,
663 				 unsigned long parent_rate)
664 {
665 	struct alchemy_fgcs_clk *c = to_fgcs_clk(hw);
666 	int sh = c->shift + 2;
667 	unsigned long div, v, flags, ret;
668 
669 	if (!rate || !parent_rate || rate > parent_rate)
670 		return -EINVAL;
671 
672 	v = alchemy_rdsys(c->reg) & (1 << 30); /* test "scale" bit */
673 	ret = alchemy_calc_div(rate, parent_rate, v ? 1 : 2,
674 			       v ? 256 : 512, &div);
675 
676 	spin_lock_irqsave(c->reglock, flags);
677 	v = alchemy_rdsys(c->reg);
678 	v &= ~(0xff << sh);
679 	v |= (div & 0xff) << sh;
680 	alchemy_wrsys(v, c->reg);
681 	spin_unlock_irqrestore(c->reglock, flags);
682 
683 	return 0;
684 }
685 
686 static unsigned long alchemy_clk_fgv2_recalc(struct clk_hw *hw,
687 					     unsigned long parent_rate)
688 {
689 	struct alchemy_fgcs_clk *c = to_fgcs_clk(hw);
690 	int sh = c->shift + 2;
691 	unsigned long v, t;
692 
693 	v = alchemy_rdsys(c->reg);
694 	t = parent_rate / (((v >> sh) & 0xff) + 1);
695 	if ((v & (1 << 30)) == 0)		/* test scale bit */
696 		t /= 2;
697 
698 	return t;
699 }
700 
701 static int alchemy_clk_fgv2_detr(struct clk_hw *hw,
702 				 struct clk_rate_request *req)
703 {
704 	struct alchemy_fgcs_clk *c = to_fgcs_clk(hw);
705 	int scale, maxdiv;
706 
707 	if (alchemy_rdsys(c->reg) & (1 << 30)) {
708 		scale = 1;
709 		maxdiv = 256;
710 	} else {
711 		scale = 2;
712 		maxdiv = 512;
713 	}
714 
715 	return alchemy_clk_fgcs_detr(hw, req, scale, maxdiv);
716 }
717 
718 /* Au1300 larger input mux, no separate disable bit, flexible divider */
719 static struct clk_ops alchemy_clkops_fgenv2 = {
720 	.recalc_rate	= alchemy_clk_fgv2_recalc,
721 	.determine_rate	= alchemy_clk_fgv2_detr,
722 	.set_rate	= alchemy_clk_fgv2_setr,
723 	.set_parent	= alchemy_clk_fgv2_setp,
724 	.get_parent	= alchemy_clk_fgv2_getp,
725 	.enable		= alchemy_clk_fgv2_en,
726 	.disable	= alchemy_clk_fgv2_dis,
727 	.is_enabled	= alchemy_clk_fgv2_isen,
728 };
729 
730 static const char * const alchemy_clk_fgv1_parents[] = {
731 	ALCHEMY_CPU_CLK, ALCHEMY_AUXPLL_CLK
732 };
733 
734 static const char * const alchemy_clk_fgv2_parents[] = {
735 	ALCHEMY_AUXPLL2_CLK, ALCHEMY_CPU_CLK, ALCHEMY_AUXPLL_CLK
736 };
737 
738 static const char * const alchemy_clk_fgen_names[] = {
739 	ALCHEMY_FG0_CLK, ALCHEMY_FG1_CLK, ALCHEMY_FG2_CLK,
740 	ALCHEMY_FG3_CLK, ALCHEMY_FG4_CLK, ALCHEMY_FG5_CLK };
741 
742 static int __init alchemy_clk_init_fgens(int ctype)
743 {
744 	struct clk *c;
745 	struct clk_init_data id;
746 	struct alchemy_fgcs_clk *a;
747 	unsigned long v;
748 	int i, ret;
749 
750 	switch (ctype) {
751 	case ALCHEMY_CPU_AU1000...ALCHEMY_CPU_AU1200:
752 		id.ops = &alchemy_clkops_fgenv1;
753 		id.parent_names = alchemy_clk_fgv1_parents;
754 		id.num_parents = 2;
755 		break;
756 	case ALCHEMY_CPU_AU1300:
757 		id.ops = &alchemy_clkops_fgenv2;
758 		id.parent_names = alchemy_clk_fgv2_parents;
759 		id.num_parents = 3;
760 		break;
761 	default:
762 		return -ENODEV;
763 	}
764 	id.flags = CLK_SET_RATE_PARENT | CLK_GET_RATE_NOCACHE;
765 
766 	a = kzalloc((sizeof(*a)) * 6, GFP_KERNEL);
767 	if (!a)
768 		return -ENOMEM;
769 
770 	spin_lock_init(&alchemy_clk_fg0_lock);
771 	spin_lock_init(&alchemy_clk_fg1_lock);
772 	ret = 0;
773 	for (i = 0; i < 6; i++) {
774 		id.name = alchemy_clk_fgen_names[i];
775 		a->shift = 10 * (i < 3 ? i : i - 3);
776 		if (i > 2) {
777 			a->reg = AU1000_SYS_FREQCTRL1;
778 			a->reglock = &alchemy_clk_fg1_lock;
779 		} else {
780 			a->reg = AU1000_SYS_FREQCTRL0;
781 			a->reglock = &alchemy_clk_fg0_lock;
782 		}
783 
784 		/* default to first parent if bootloader has set
785 		 * the mux to disabled state.
786 		 */
787 		if (ctype == ALCHEMY_CPU_AU1300) {
788 			v = alchemy_rdsys(a->reg);
789 			a->parent = (v >> a->shift) & 3;
790 			if (!a->parent) {
791 				a->parent = 1;
792 				a->isen = 0;
793 			} else
794 				a->isen = 1;
795 		}
796 
797 		a->hw.init = &id;
798 		c = clk_register(NULL, &a->hw);
799 		if (IS_ERR(c))
800 			ret++;
801 		else
802 			clk_register_clkdev(c, id.name, NULL);
803 		a++;
804 	}
805 
806 	return ret;
807 }
808 
809 /* internal sources muxes *********************************************/
810 
811 static int alchemy_clk_csrc_isen(struct clk_hw *hw)
812 {
813 	struct alchemy_fgcs_clk *c = to_fgcs_clk(hw);
814 	unsigned long v = alchemy_rdsys(c->reg);
815 
816 	return (((v >> c->shift) >> 2) & 7) != 0;
817 }
818 
819 static void __alchemy_clk_csrc_en(struct alchemy_fgcs_clk *c)
820 {
821 	unsigned long v = alchemy_rdsys(c->reg);
822 
823 	v &= ~((7 << 2) << c->shift);
824 	v |= ((c->parent & 7) << 2) << c->shift;
825 	alchemy_wrsys(v, c->reg);
826 	c->isen = 1;
827 }
828 
829 static int alchemy_clk_csrc_en(struct clk_hw *hw)
830 {
831 	struct alchemy_fgcs_clk *c = to_fgcs_clk(hw);
832 	unsigned long flags;
833 
834 	/* enable by setting the previous parent clock */
835 	spin_lock_irqsave(c->reglock, flags);
836 	__alchemy_clk_csrc_en(c);
837 	spin_unlock_irqrestore(c->reglock, flags);
838 
839 	return 0;
840 }
841 
842 static void alchemy_clk_csrc_dis(struct clk_hw *hw)
843 {
844 	struct alchemy_fgcs_clk *c = to_fgcs_clk(hw);
845 	unsigned long v, flags;
846 
847 	spin_lock_irqsave(c->reglock, flags);
848 	v = alchemy_rdsys(c->reg);
849 	v &= ~((3 << 2) << c->shift);	/* mux to "disabled" state */
850 	alchemy_wrsys(v, c->reg);
851 	c->isen = 0;
852 	spin_unlock_irqrestore(c->reglock, flags);
853 }
854 
855 static int alchemy_clk_csrc_setp(struct clk_hw *hw, u8 index)
856 {
857 	struct alchemy_fgcs_clk *c = to_fgcs_clk(hw);
858 	unsigned long flags;
859 
860 	spin_lock_irqsave(c->reglock, flags);
861 	c->parent = index + 1;	/* value to write to register */
862 	if (c->isen)
863 		__alchemy_clk_csrc_en(c);
864 	spin_unlock_irqrestore(c->reglock, flags);
865 
866 	return 0;
867 }
868 
869 static u8 alchemy_clk_csrc_getp(struct clk_hw *hw)
870 {
871 	struct alchemy_fgcs_clk *c = to_fgcs_clk(hw);
872 
873 	return c->parent - 1;
874 }
875 
876 static unsigned long alchemy_clk_csrc_recalc(struct clk_hw *hw,
877 					     unsigned long parent_rate)
878 {
879 	struct alchemy_fgcs_clk *c = to_fgcs_clk(hw);
880 	unsigned long v = (alchemy_rdsys(c->reg) >> c->shift) & 3;
881 
882 	return parent_rate / c->dt[v];
883 }
884 
885 static int alchemy_clk_csrc_setr(struct clk_hw *hw, unsigned long rate,
886 				 unsigned long parent_rate)
887 {
888 	struct alchemy_fgcs_clk *c = to_fgcs_clk(hw);
889 	unsigned long d, v, flags;
890 	int i;
891 
892 	if (!rate || !parent_rate || rate > parent_rate)
893 		return -EINVAL;
894 
895 	d = (parent_rate + (rate / 2)) / rate;
896 	if (d > 4)
897 		return -EINVAL;
898 	if ((d == 3) && (c->dt[2] != 3))
899 		d = 4;
900 
901 	for (i = 0; i < 4; i++)
902 		if (c->dt[i] == d)
903 			break;
904 
905 	if (i >= 4)
906 		return -EINVAL;	/* oops */
907 
908 	spin_lock_irqsave(c->reglock, flags);
909 	v = alchemy_rdsys(c->reg);
910 	v &= ~(3 << c->shift);
911 	v |= (i & 3) << c->shift;
912 	alchemy_wrsys(v, c->reg);
913 	spin_unlock_irqrestore(c->reglock, flags);
914 
915 	return 0;
916 }
917 
918 static int alchemy_clk_csrc_detr(struct clk_hw *hw,
919 				 struct clk_rate_request *req)
920 {
921 	struct alchemy_fgcs_clk *c = to_fgcs_clk(hw);
922 	int scale = c->dt[2] == 3 ? 1 : 2; /* au1300 check */
923 
924 	return alchemy_clk_fgcs_detr(hw, req, scale, 4);
925 }
926 
927 static struct clk_ops alchemy_clkops_csrc = {
928 	.recalc_rate	= alchemy_clk_csrc_recalc,
929 	.determine_rate	= alchemy_clk_csrc_detr,
930 	.set_rate	= alchemy_clk_csrc_setr,
931 	.set_parent	= alchemy_clk_csrc_setp,
932 	.get_parent	= alchemy_clk_csrc_getp,
933 	.enable		= alchemy_clk_csrc_en,
934 	.disable	= alchemy_clk_csrc_dis,
935 	.is_enabled	= alchemy_clk_csrc_isen,
936 };
937 
938 static const char * const alchemy_clk_csrc_parents[] = {
939 	/* disabled at index 0 */ ALCHEMY_AUXPLL_CLK,
940 	ALCHEMY_FG0_CLK, ALCHEMY_FG1_CLK, ALCHEMY_FG2_CLK,
941 	ALCHEMY_FG3_CLK, ALCHEMY_FG4_CLK, ALCHEMY_FG5_CLK
942 };
943 
944 /* divider tables */
945 static int alchemy_csrc_dt1[] = { 1, 4, 1, 2 };	/* rest */
946 static int alchemy_csrc_dt2[] = { 1, 4, 3, 2 };	/* Au1300 */
947 
948 static int __init alchemy_clk_setup_imux(int ctype)
949 {
950 	struct alchemy_fgcs_clk *a;
951 	const char * const *names;
952 	struct clk_init_data id;
953 	unsigned long v;
954 	int i, ret, *dt;
955 	struct clk *c;
956 
957 	id.ops = &alchemy_clkops_csrc;
958 	id.parent_names = alchemy_clk_csrc_parents;
959 	id.num_parents = 7;
960 	id.flags = CLK_SET_RATE_PARENT | CLK_GET_RATE_NOCACHE;
961 
962 	dt = alchemy_csrc_dt1;
963 	switch (ctype) {
964 	case ALCHEMY_CPU_AU1000:
965 		names = alchemy_au1000_intclknames;
966 		break;
967 	case ALCHEMY_CPU_AU1500:
968 		names = alchemy_au1500_intclknames;
969 		break;
970 	case ALCHEMY_CPU_AU1100:
971 		names = alchemy_au1100_intclknames;
972 		break;
973 	case ALCHEMY_CPU_AU1550:
974 		names = alchemy_au1550_intclknames;
975 		break;
976 	case ALCHEMY_CPU_AU1200:
977 		names = alchemy_au1200_intclknames;
978 		break;
979 	case ALCHEMY_CPU_AU1300:
980 		dt = alchemy_csrc_dt2;
981 		names = alchemy_au1300_intclknames;
982 		break;
983 	default:
984 		return -ENODEV;
985 	}
986 
987 	a = kzalloc((sizeof(*a)) * 6, GFP_KERNEL);
988 	if (!a)
989 		return -ENOMEM;
990 
991 	spin_lock_init(&alchemy_clk_csrc_lock);
992 	ret = 0;
993 
994 	for (i = 0; i < 6; i++) {
995 		id.name = names[i];
996 		if (!id.name)
997 			goto next;
998 
999 		a->shift = i * 5;
1000 		a->reg = AU1000_SYS_CLKSRC;
1001 		a->reglock = &alchemy_clk_csrc_lock;
1002 		a->dt = dt;
1003 
1004 		/* default to first parent clock if mux is initially
1005 		 * set to disabled state.
1006 		 */
1007 		v = alchemy_rdsys(a->reg);
1008 		a->parent = ((v >> a->shift) >> 2) & 7;
1009 		if (!a->parent) {
1010 			a->parent = 1;
1011 			a->isen = 0;
1012 		} else
1013 			a->isen = 1;
1014 
1015 		a->hw.init = &id;
1016 		c = clk_register(NULL, &a->hw);
1017 		if (IS_ERR(c))
1018 			ret++;
1019 		else
1020 			clk_register_clkdev(c, id.name, NULL);
1021 next:
1022 		a++;
1023 	}
1024 
1025 	return ret;
1026 }
1027 
1028 
1029 /**********************************************************************/
1030 
1031 
1032 #define ERRCK(x)						\
1033 	if (IS_ERR(x)) {					\
1034 		ret = PTR_ERR(x);				\
1035 		goto out;					\
1036 	}
1037 
1038 static int __init alchemy_clk_init(void)
1039 {
1040 	int ctype = alchemy_get_cputype(), ret, i;
1041 	struct clk_aliastable *t = alchemy_clk_aliases;
1042 	struct clk *c;
1043 
1044 	/* Root of the Alchemy clock tree: external 12MHz crystal osc */
1045 	c = clk_register_fixed_rate(NULL, ALCHEMY_ROOT_CLK, NULL,
1046 					   0, ALCHEMY_ROOTCLK_RATE);
1047 	ERRCK(c)
1048 
1049 	/* CPU core clock */
1050 	c = alchemy_clk_setup_cpu(ALCHEMY_ROOT_CLK, ctype);
1051 	ERRCK(c)
1052 
1053 	/* AUXPLLs: max 1GHz on Au1300, 748MHz on older models */
1054 	i = (ctype == ALCHEMY_CPU_AU1300) ? 84 : 63;
1055 	c = alchemy_clk_setup_aux(ALCHEMY_ROOT_CLK, ALCHEMY_AUXPLL_CLK,
1056 				  i, AU1000_SYS_AUXPLL);
1057 	ERRCK(c)
1058 
1059 	if (ctype == ALCHEMY_CPU_AU1300) {
1060 		c = alchemy_clk_setup_aux(ALCHEMY_ROOT_CLK,
1061 					  ALCHEMY_AUXPLL2_CLK, i,
1062 					  AU1300_SYS_AUXPLL2);
1063 		ERRCK(c)
1064 	}
1065 
1066 	/* sysbus clock: cpu core clock divided by 2, 3 or 4 */
1067 	c = alchemy_clk_setup_sysbus(ALCHEMY_CPU_CLK);
1068 	ERRCK(c)
1069 
1070 	/* peripheral clock: runs at half rate of sysbus clk */
1071 	c = alchemy_clk_setup_periph(ALCHEMY_SYSBUS_CLK);
1072 	ERRCK(c)
1073 
1074 	/* SDR/DDR memory clock */
1075 	c = alchemy_clk_setup_mem(ALCHEMY_SYSBUS_CLK, ctype);
1076 	ERRCK(c)
1077 
1078 	/* L/RCLK: external static bus clock for synchronous mode */
1079 	c = alchemy_clk_setup_lrclk(ALCHEMY_PERIPH_CLK, ctype);
1080 	ERRCK(c)
1081 
1082 	/* Frequency dividers 0-5 */
1083 	ret = alchemy_clk_init_fgens(ctype);
1084 	if (ret) {
1085 		ret = -ENODEV;
1086 		goto out;
1087 	}
1088 
1089 	/* diving muxes for internal sources */
1090 	ret = alchemy_clk_setup_imux(ctype);
1091 	if (ret) {
1092 		ret = -ENODEV;
1093 		goto out;
1094 	}
1095 
1096 	/* set up aliases drivers might look for */
1097 	while (t->base) {
1098 		if (t->cputype == ctype)
1099 			clk_add_alias(t->alias, NULL, t->base, NULL);
1100 		t++;
1101 	}
1102 
1103 	pr_info("Alchemy clocktree installed\n");
1104 	return 0;
1105 
1106 out:
1107 	return ret;
1108 }
1109 postcore_initcall(alchemy_clk_init);
1110