xref: /linux/arch/mips/alchemy/common/clock.c (revision 6a74422b9710e987c7d6b85a1ade7330b1e61626)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * Alchemy clocks.
4  *
5  * Exposes all configurable internal clock sources to the clk framework.
6  *
7  * We have:
8  *  - Root source, usually 12MHz supplied by an external crystal
9  *  - 3 PLLs which generate multiples of root rate [AUX, CPU, AUX2]
10  *
11  * Dividers:
12  *  - 6 clock dividers with:
13  *   * selectable source [one of the PLLs],
14  *   * output divided between [2 .. 512 in steps of 2] (!Au1300)
15  *     or [1 .. 256 in steps of 1] (Au1300),
16  *   * can be enabled individually.
17  *
18  * - up to 6 "internal" (fixed) consumers which:
19  *   * take either AUXPLL or one of the above 6 dividers as input,
20  *   * divide this input by 1, 2, or 4 (and 3 on Au1300).
21  *   * can be disabled separately.
22  *
23  * Misc clocks:
24  * - sysbus clock: CPU core clock (CPUPLL) divided by 2, 3 or 4.
25  *    depends on board design and should be set by bootloader, read-only.
26  * - peripheral clock: half the rate of sysbus clock, source for a lot
27  *    of peripheral blocks, read-only.
28  * - memory clock: clk rate to main memory chips, depends on board
29  *    design and is read-only,
30  * - lrclk: the static bus clock signal for synchronous operation.
31  *    depends on board design, must be set by bootloader,
32  *    but may be required to correctly configure devices attached to
33  *    the static bus. The Au1000/1500/1100 manuals call it LCLK, on
34  *    later models it's called RCLK.
35  */
36 
37 #include <linux/init.h>
38 #include <linux/io.h>
39 #include <linux/clk.h>
40 #include <linux/clk-provider.h>
41 #include <linux/clkdev.h>
42 #include <linux/slab.h>
43 #include <linux/spinlock.h>
44 #include <linux/types.h>
45 #include <asm/mach-au1x00/au1000.h>
46 
47 /* Base clock: 12MHz is the default in all databooks, and I haven't
48  * found any board yet which uses a different rate.
49  */
50 #define ALCHEMY_ROOTCLK_RATE	12000000
51 
52 /*
53  * the internal sources which can be driven by the PLLs and dividers.
54  * Names taken from the databooks, refer to them for more information,
55  * especially which ones are share a clock line.
56  */
57 static const char * const alchemy_au1300_intclknames[] = {
58 	"lcd_intclk", "gpemgp_clk", "maempe_clk", "maebsa_clk",
59 	"EXTCLK0", "EXTCLK1"
60 };
61 
62 static const char * const alchemy_au1200_intclknames[] = {
63 	"lcd_intclk", NULL, NULL, NULL, "EXTCLK0", "EXTCLK1"
64 };
65 
66 static const char * const alchemy_au1550_intclknames[] = {
67 	"usb_clk", "psc0_intclk", "psc1_intclk", "pci_clko",
68 	"EXTCLK0", "EXTCLK1"
69 };
70 
71 static const char * const alchemy_au1100_intclknames[] = {
72 	"usb_clk", "lcd_intclk", NULL, "i2s_clk", "EXTCLK0", "EXTCLK1"
73 };
74 
75 static const char * const alchemy_au1500_intclknames[] = {
76 	NULL, "usbd_clk", "usbh_clk", "pci_clko", "EXTCLK0", "EXTCLK1"
77 };
78 
79 static const char * const alchemy_au1000_intclknames[] = {
80 	"irda_clk", "usbd_clk", "usbh_clk", "i2s_clk", "EXTCLK0",
81 	"EXTCLK1"
82 };
83 
84 /* aliases for a few on-chip sources which are either shared
85  * or have gone through name changes.
86  */
87 static struct clk_aliastable {
88 	char *alias;
89 	char *base;
90 	int cputype;
91 } alchemy_clk_aliases[] __initdata = {
92 	{ "usbh_clk", "usb_clk",    ALCHEMY_CPU_AU1100 },
93 	{ "usbd_clk", "usb_clk",    ALCHEMY_CPU_AU1100 },
94 	{ "irda_clk", "usb_clk",    ALCHEMY_CPU_AU1100 },
95 	{ "usbh_clk", "usb_clk",    ALCHEMY_CPU_AU1550 },
96 	{ "usbd_clk", "usb_clk",    ALCHEMY_CPU_AU1550 },
97 	{ "psc2_intclk", "usb_clk", ALCHEMY_CPU_AU1550 },
98 	{ "psc3_intclk", "EXTCLK0", ALCHEMY_CPU_AU1550 },
99 	{ "psc0_intclk", "EXTCLK0", ALCHEMY_CPU_AU1200 },
100 	{ "psc1_intclk", "EXTCLK1", ALCHEMY_CPU_AU1200 },
101 	{ "psc0_intclk", "EXTCLK0", ALCHEMY_CPU_AU1300 },
102 	{ "psc2_intclk", "EXTCLK0", ALCHEMY_CPU_AU1300 },
103 	{ "psc1_intclk", "EXTCLK1", ALCHEMY_CPU_AU1300 },
104 	{ "psc3_intclk", "EXTCLK1", ALCHEMY_CPU_AU1300 },
105 
106 	{ NULL, NULL, 0 },
107 };
108 
109 #define IOMEM(x)	((void __iomem *)(KSEG1ADDR(CPHYSADDR(x))))
110 
111 /* access locks to SYS_FREQCTRL0/1 and SYS_CLKSRC registers */
112 static spinlock_t alchemy_clk_fg0_lock;
113 static spinlock_t alchemy_clk_fg1_lock;
114 static DEFINE_SPINLOCK(alchemy_clk_csrc_lock);
115 
116 /* CPU Core clock *****************************************************/
117 
alchemy_clk_cpu_recalc(struct clk_hw * hw,unsigned long parent_rate)118 static unsigned long alchemy_clk_cpu_recalc(struct clk_hw *hw,
119 					    unsigned long parent_rate)
120 {
121 	unsigned long t;
122 
123 	/*
124 	 * On early Au1000, sys_cpupll was write-only. Since these
125 	 * silicon versions of Au1000 are not sold, we don't bend
126 	 * over backwards trying to determine the frequency.
127 	 */
128 	if (unlikely(au1xxx_cpu_has_pll_wo()))
129 		t = 396000000;
130 	else {
131 		t = alchemy_rdsys(AU1000_SYS_CPUPLL) & 0x7f;
132 		if (alchemy_get_cputype() < ALCHEMY_CPU_AU1300)
133 			t &= 0x3f;
134 		t *= parent_rate;
135 	}
136 
137 	return t;
138 }
139 
alchemy_set_lpj(void)140 void __init alchemy_set_lpj(void)
141 {
142 	preset_lpj = alchemy_clk_cpu_recalc(NULL, ALCHEMY_ROOTCLK_RATE);
143 	preset_lpj /= 2 * HZ;
144 }
145 
146 static const struct clk_ops alchemy_clkops_cpu = {
147 	.recalc_rate	= alchemy_clk_cpu_recalc,
148 };
149 
alchemy_clk_setup_cpu(const char * parent_name,int ctype)150 static struct clk __init *alchemy_clk_setup_cpu(const char *parent_name,
151 						int ctype)
152 {
153 	struct clk_init_data id;
154 	struct clk_hw *h;
155 	struct clk *clk;
156 
157 	h = kzalloc(sizeof(*h), GFP_KERNEL);
158 	if (!h)
159 		return ERR_PTR(-ENOMEM);
160 
161 	id.name = ALCHEMY_CPU_CLK;
162 	id.parent_names = &parent_name;
163 	id.num_parents = 1;
164 	id.flags = 0;
165 	id.ops = &alchemy_clkops_cpu;
166 	h->init = &id;
167 
168 	clk = clk_register(NULL, h);
169 	if (IS_ERR(clk)) {
170 		pr_err("failed to register clock\n");
171 		kfree(h);
172 	}
173 
174 	return clk;
175 }
176 
177 /* AUXPLLs ************************************************************/
178 
179 struct alchemy_auxpll_clk {
180 	struct clk_hw hw;
181 	unsigned long reg;	/* au1300 has also AUXPLL2 */
182 	int maxmult;		/* max multiplier */
183 };
184 #define to_auxpll_clk(x) container_of(x, struct alchemy_auxpll_clk, hw)
185 
alchemy_clk_aux_recalc(struct clk_hw * hw,unsigned long parent_rate)186 static unsigned long alchemy_clk_aux_recalc(struct clk_hw *hw,
187 					    unsigned long parent_rate)
188 {
189 	struct alchemy_auxpll_clk *a = to_auxpll_clk(hw);
190 
191 	return (alchemy_rdsys(a->reg) & 0xff) * parent_rate;
192 }
193 
alchemy_clk_aux_setr(struct clk_hw * hw,unsigned long rate,unsigned long parent_rate)194 static int alchemy_clk_aux_setr(struct clk_hw *hw,
195 				unsigned long rate,
196 				unsigned long parent_rate)
197 {
198 	struct alchemy_auxpll_clk *a = to_auxpll_clk(hw);
199 	unsigned long d = rate;
200 
201 	if (rate)
202 		d /= parent_rate;
203 	else
204 		d = 0;
205 
206 	/* minimum is 84MHz, max is 756-1032 depending on variant */
207 	if (((d < 7) && (d != 0)) || (d > a->maxmult))
208 		return -EINVAL;
209 
210 	alchemy_wrsys(d, a->reg);
211 	return 0;
212 }
213 
alchemy_clk_aux_determine_rate(struct clk_hw * hw,struct clk_rate_request * req)214 static int alchemy_clk_aux_determine_rate(struct clk_hw *hw,
215 					  struct clk_rate_request *req)
216 {
217 	struct alchemy_auxpll_clk *a = to_auxpll_clk(hw);
218 	unsigned long mult;
219 
220 	if (!req->rate || !req->best_parent_rate) {
221 		req->rate = 0;
222 
223 		return 0;
224 	}
225 
226 	mult = req->rate / req->best_parent_rate;
227 
228 	if (mult && (mult < 7))
229 		mult = 7;
230 	if (mult > a->maxmult)
231 		mult = a->maxmult;
232 
233 	req->rate = req->best_parent_rate * mult;
234 
235 	return 0;
236 }
237 
238 static const struct clk_ops alchemy_clkops_aux = {
239 	.recalc_rate	= alchemy_clk_aux_recalc,
240 	.set_rate	= alchemy_clk_aux_setr,
241 	.determine_rate = alchemy_clk_aux_determine_rate,
242 };
243 
alchemy_clk_setup_aux(const char * parent_name,char * name,int maxmult,unsigned long reg)244 static struct clk __init *alchemy_clk_setup_aux(const char *parent_name,
245 						char *name, int maxmult,
246 						unsigned long reg)
247 {
248 	struct clk_init_data id;
249 	struct clk *c;
250 	struct alchemy_auxpll_clk *a;
251 
252 	a = kzalloc(sizeof(*a), GFP_KERNEL);
253 	if (!a)
254 		return ERR_PTR(-ENOMEM);
255 
256 	id.name = name;
257 	id.parent_names = &parent_name;
258 	id.num_parents = 1;
259 	id.flags = CLK_GET_RATE_NOCACHE;
260 	id.ops = &alchemy_clkops_aux;
261 
262 	a->reg = reg;
263 	a->maxmult = maxmult;
264 	a->hw.init = &id;
265 
266 	c = clk_register(NULL, &a->hw);
267 	if (!IS_ERR(c))
268 		clk_register_clkdev(c, name, NULL);
269 	else
270 		kfree(a);
271 
272 	return c;
273 }
274 
275 /* sysbus_clk *********************************************************/
276 
alchemy_clk_setup_sysbus(const char * pn)277 static struct clk __init  *alchemy_clk_setup_sysbus(const char *pn)
278 {
279 	unsigned long v = (alchemy_rdsys(AU1000_SYS_POWERCTRL) & 3) + 2;
280 	struct clk *c;
281 
282 	c = clk_register_fixed_factor(NULL, ALCHEMY_SYSBUS_CLK,
283 				      pn, 0, 1, v);
284 	if (!IS_ERR(c))
285 		clk_register_clkdev(c, ALCHEMY_SYSBUS_CLK, NULL);
286 	return c;
287 }
288 
289 /* Peripheral Clock ***************************************************/
290 
alchemy_clk_setup_periph(const char * pn)291 static struct clk __init *alchemy_clk_setup_periph(const char *pn)
292 {
293 	/* Peripheral clock runs at half the rate of sysbus clk */
294 	struct clk *c;
295 
296 	c = clk_register_fixed_factor(NULL, ALCHEMY_PERIPH_CLK,
297 				      pn, 0, 1, 2);
298 	if (!IS_ERR(c))
299 		clk_register_clkdev(c, ALCHEMY_PERIPH_CLK, NULL);
300 	return c;
301 }
302 
303 /* mem clock **********************************************************/
304 
alchemy_clk_setup_mem(const char * pn,int ct)305 static struct clk __init *alchemy_clk_setup_mem(const char *pn, int ct)
306 {
307 	void __iomem *addr = IOMEM(AU1000_MEM_PHYS_ADDR);
308 	unsigned long v;
309 	struct clk *c;
310 	int div;
311 
312 	switch (ct) {
313 	case ALCHEMY_CPU_AU1550:
314 	case ALCHEMY_CPU_AU1200:
315 		v = __raw_readl(addr + AU1550_MEM_SDCONFIGB);
316 		div = (v & (1 << 15)) ? 1 : 2;
317 		break;
318 	case ALCHEMY_CPU_AU1300:
319 		v = __raw_readl(addr + AU1550_MEM_SDCONFIGB);
320 		div = (v & (1 << 31)) ? 1 : 2;
321 		break;
322 	case ALCHEMY_CPU_AU1000:
323 	case ALCHEMY_CPU_AU1500:
324 	case ALCHEMY_CPU_AU1100:
325 	default:
326 		div = 2;
327 		break;
328 	}
329 
330 	c = clk_register_fixed_factor(NULL, ALCHEMY_MEM_CLK, pn,
331 				      0, 1, div);
332 	if (!IS_ERR(c))
333 		clk_register_clkdev(c, ALCHEMY_MEM_CLK, NULL);
334 	return c;
335 }
336 
337 /* lrclk: external synchronous static bus clock ***********************/
338 
alchemy_clk_setup_lrclk(const char * pn,int t)339 static struct clk __init *alchemy_clk_setup_lrclk(const char *pn, int t)
340 {
341 	/* Au1000, Au1500: MEM_STCFG0[11]: If bit is set, lrclk=pclk/5,
342 	 * otherwise lrclk=pclk/4.
343 	 * All other variants: MEM_STCFG0[15:13] = divisor.
344 	 * L/RCLK = periph_clk / (divisor + 1)
345 	 * On Au1000, Au1500, Au1100 it's called LCLK,
346 	 * on later models it's called RCLK, but it's the same thing.
347 	 */
348 	struct clk *c;
349 	unsigned long v = alchemy_rdsmem(AU1000_MEM_STCFG0);
350 
351 	switch (t) {
352 	case ALCHEMY_CPU_AU1000:
353 	case ALCHEMY_CPU_AU1500:
354 		v = 4 + ((v >> 11) & 1);
355 		break;
356 	default:	/* all other models */
357 		v = ((v >> 13) & 7) + 1;
358 	}
359 	c = clk_register_fixed_factor(NULL, ALCHEMY_LR_CLK,
360 				      pn, 0, 1, v);
361 	if (!IS_ERR(c))
362 		clk_register_clkdev(c, ALCHEMY_LR_CLK, NULL);
363 	return c;
364 }
365 
366 /* Clock dividers and muxes *******************************************/
367 
368 /* data for fgen and csrc mux-dividers */
369 struct alchemy_fgcs_clk {
370 	struct clk_hw hw;
371 	spinlock_t *reglock;	/* register lock		  */
372 	unsigned long reg;	/* SYS_FREQCTRL0/1		  */
373 	int shift;		/* offset in register		  */
374 	int parent;		/* parent before disable [Au1300] */
375 	int isen;		/* is it enabled?		  */
376 	int *dt;		/* dividertable for csrc	  */
377 };
378 #define to_fgcs_clk(x) container_of(x, struct alchemy_fgcs_clk, hw)
379 
alchemy_calc_div(unsigned long rate,unsigned long prate,int scale,int maxdiv,unsigned long * rv)380 static long alchemy_calc_div(unsigned long rate, unsigned long prate,
381 			       int scale, int maxdiv, unsigned long *rv)
382 {
383 	long div1, div2;
384 
385 	div1 = prate / rate;
386 	if ((prate / div1) > rate)
387 		div1++;
388 
389 	if (scale == 2) {	/* only div-by-multiple-of-2 possible */
390 		if (div1 & 1)
391 			div1++;	/* stay <=prate */
392 	}
393 
394 	div2 = (div1 / scale) - 1;	/* value to write to register */
395 
396 	if (div2 > maxdiv)
397 		div2 = maxdiv;
398 	if (rv)
399 		*rv = div2;
400 
401 	div1 = ((div2 + 1) * scale);
402 	return div1;
403 }
404 
alchemy_clk_fgcs_detr(struct clk_hw * hw,struct clk_rate_request * req,int scale,int maxdiv)405 static int alchemy_clk_fgcs_detr(struct clk_hw *hw,
406 				 struct clk_rate_request *req,
407 				 int scale, int maxdiv)
408 {
409 	struct clk_hw *pc, *bpc, *free;
410 	long tdv, tpr, pr, nr, br, bpr, diff, lastdiff;
411 	int j;
412 
413 	lastdiff = INT_MAX;
414 	bpr = 0;
415 	bpc = NULL;
416 	br = -EINVAL;
417 	free = NULL;
418 
419 	/* look at the rates each enabled parent supplies and select
420 	 * the one that gets closest to but not over the requested rate.
421 	 */
422 	for (j = 0; j < 7; j++) {
423 		pc = clk_hw_get_parent_by_index(hw, j);
424 		if (!pc)
425 			break;
426 
427 		/* if this parent is currently unused, remember it.
428 		 * XXX: we would actually want clk_has_active_children()
429 		 * but this is a good-enough approximation for now.
430 		 */
431 		if (!clk_hw_is_prepared(pc)) {
432 			if (!free)
433 				free = pc;
434 		}
435 
436 		pr = clk_hw_get_rate(pc);
437 		if (pr < req->rate)
438 			continue;
439 
440 		/* what can hardware actually provide */
441 		tdv = alchemy_calc_div(req->rate, pr, scale, maxdiv, NULL);
442 		nr = pr / tdv;
443 		diff = req->rate - nr;
444 		if (nr > req->rate)
445 			continue;
446 
447 		if (diff < lastdiff) {
448 			lastdiff = diff;
449 			bpr = pr;
450 			bpc = pc;
451 			br = nr;
452 		}
453 		if (diff == 0)
454 			break;
455 	}
456 
457 	/* if we couldn't get the exact rate we wanted from the enabled
458 	 * parents, maybe we can tell an available disabled/inactive one
459 	 * to give us a rate we can divide down to the requested rate.
460 	 */
461 	if (lastdiff && free) {
462 		for (j = (maxdiv == 4) ? 1 : scale; j <= maxdiv; j += scale) {
463 			tpr = req->rate * j;
464 			if (tpr < 0)
465 				break;
466 			pr = clk_hw_round_rate(free, tpr);
467 
468 			tdv = alchemy_calc_div(req->rate, pr, scale, maxdiv,
469 					       NULL);
470 			nr = pr / tdv;
471 			diff = req->rate - nr;
472 			if (nr > req->rate)
473 				continue;
474 			if (diff < lastdiff) {
475 				lastdiff = diff;
476 				bpr = pr;
477 				bpc = free;
478 				br = nr;
479 			}
480 			if (diff == 0)
481 				break;
482 		}
483 	}
484 
485 	if (br < 0)
486 		return br;
487 
488 	req->best_parent_rate = bpr;
489 	req->best_parent_hw = bpc;
490 	req->rate = br;
491 
492 	return 0;
493 }
494 
alchemy_clk_fgv1_en(struct clk_hw * hw)495 static int alchemy_clk_fgv1_en(struct clk_hw *hw)
496 {
497 	struct alchemy_fgcs_clk *c = to_fgcs_clk(hw);
498 	unsigned long v, flags;
499 
500 	spin_lock_irqsave(c->reglock, flags);
501 	v = alchemy_rdsys(c->reg);
502 	v |= (1 << 1) << c->shift;
503 	alchemy_wrsys(v, c->reg);
504 	spin_unlock_irqrestore(c->reglock, flags);
505 
506 	return 0;
507 }
508 
alchemy_clk_fgv1_isen(struct clk_hw * hw)509 static int alchemy_clk_fgv1_isen(struct clk_hw *hw)
510 {
511 	struct alchemy_fgcs_clk *c = to_fgcs_clk(hw);
512 	unsigned long v = alchemy_rdsys(c->reg) >> (c->shift + 1);
513 
514 	return v & 1;
515 }
516 
alchemy_clk_fgv1_dis(struct clk_hw * hw)517 static void alchemy_clk_fgv1_dis(struct clk_hw *hw)
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 	v &= ~((1 << 1) << c->shift);
525 	alchemy_wrsys(v, c->reg);
526 	spin_unlock_irqrestore(c->reglock, flags);
527 }
528 
alchemy_clk_fgv1_setp(struct clk_hw * hw,u8 index)529 static int alchemy_clk_fgv1_setp(struct clk_hw *hw, u8 index)
530 {
531 	struct alchemy_fgcs_clk *c = to_fgcs_clk(hw);
532 	unsigned long v, flags;
533 
534 	spin_lock_irqsave(c->reglock, flags);
535 	v = alchemy_rdsys(c->reg);
536 	if (index)
537 		v |= (1 << c->shift);
538 	else
539 		v &= ~(1 << c->shift);
540 	alchemy_wrsys(v, c->reg);
541 	spin_unlock_irqrestore(c->reglock, flags);
542 
543 	return 0;
544 }
545 
alchemy_clk_fgv1_getp(struct clk_hw * hw)546 static u8 alchemy_clk_fgv1_getp(struct clk_hw *hw)
547 {
548 	struct alchemy_fgcs_clk *c = to_fgcs_clk(hw);
549 
550 	return (alchemy_rdsys(c->reg) >> c->shift) & 1;
551 }
552 
alchemy_clk_fgv1_setr(struct clk_hw * hw,unsigned long rate,unsigned long parent_rate)553 static int alchemy_clk_fgv1_setr(struct clk_hw *hw, unsigned long rate,
554 				 unsigned long parent_rate)
555 {
556 	struct alchemy_fgcs_clk *c = to_fgcs_clk(hw);
557 	unsigned long div, v, flags, ret;
558 	int sh = c->shift + 2;
559 
560 	if (!rate || !parent_rate || rate > (parent_rate / 2))
561 		return -EINVAL;
562 	ret = alchemy_calc_div(rate, parent_rate, 2, 512, &div);
563 	spin_lock_irqsave(c->reglock, flags);
564 	v = alchemy_rdsys(c->reg);
565 	v &= ~(0xff << sh);
566 	v |= div << sh;
567 	alchemy_wrsys(v, c->reg);
568 	spin_unlock_irqrestore(c->reglock, flags);
569 
570 	return 0;
571 }
572 
alchemy_clk_fgv1_recalc(struct clk_hw * hw,unsigned long parent_rate)573 static unsigned long alchemy_clk_fgv1_recalc(struct clk_hw *hw,
574 					     unsigned long parent_rate)
575 {
576 	struct alchemy_fgcs_clk *c = to_fgcs_clk(hw);
577 	unsigned long v = alchemy_rdsys(c->reg) >> (c->shift + 2);
578 
579 	v = ((v & 0xff) + 1) * 2;
580 	return parent_rate / v;
581 }
582 
alchemy_clk_fgv1_detr(struct clk_hw * hw,struct clk_rate_request * req)583 static int alchemy_clk_fgv1_detr(struct clk_hw *hw,
584 				 struct clk_rate_request *req)
585 {
586 	return alchemy_clk_fgcs_detr(hw, req, 2, 512);
587 }
588 
589 /* Au1000, Au1100, Au15x0, Au12x0 */
590 static const struct clk_ops alchemy_clkops_fgenv1 = {
591 	.recalc_rate	= alchemy_clk_fgv1_recalc,
592 	.determine_rate	= alchemy_clk_fgv1_detr,
593 	.set_rate	= alchemy_clk_fgv1_setr,
594 	.set_parent	= alchemy_clk_fgv1_setp,
595 	.get_parent	= alchemy_clk_fgv1_getp,
596 	.enable		= alchemy_clk_fgv1_en,
597 	.disable	= alchemy_clk_fgv1_dis,
598 	.is_enabled	= alchemy_clk_fgv1_isen,
599 };
600 
__alchemy_clk_fgv2_en(struct alchemy_fgcs_clk * c)601 static void __alchemy_clk_fgv2_en(struct alchemy_fgcs_clk *c)
602 {
603 	unsigned long v = alchemy_rdsys(c->reg);
604 
605 	v &= ~(3 << c->shift);
606 	v |= (c->parent & 3) << c->shift;
607 	alchemy_wrsys(v, c->reg);
608 	c->isen = 1;
609 }
610 
alchemy_clk_fgv2_en(struct clk_hw * hw)611 static int alchemy_clk_fgv2_en(struct clk_hw *hw)
612 {
613 	struct alchemy_fgcs_clk *c = to_fgcs_clk(hw);
614 	unsigned long flags;
615 
616 	/* enable by setting the previous parent clock */
617 	spin_lock_irqsave(c->reglock, flags);
618 	__alchemy_clk_fgv2_en(c);
619 	spin_unlock_irqrestore(c->reglock, flags);
620 
621 	return 0;
622 }
623 
alchemy_clk_fgv2_isen(struct clk_hw * hw)624 static int alchemy_clk_fgv2_isen(struct clk_hw *hw)
625 {
626 	struct alchemy_fgcs_clk *c = to_fgcs_clk(hw);
627 
628 	return ((alchemy_rdsys(c->reg) >> c->shift) & 3) != 0;
629 }
630 
alchemy_clk_fgv2_dis(struct clk_hw * hw)631 static void alchemy_clk_fgv2_dis(struct clk_hw *hw)
632 {
633 	struct alchemy_fgcs_clk *c = to_fgcs_clk(hw);
634 	unsigned long v, flags;
635 
636 	spin_lock_irqsave(c->reglock, flags);
637 	v = alchemy_rdsys(c->reg);
638 	v &= ~(3 << c->shift);	/* set input mux to "disabled" state */
639 	alchemy_wrsys(v, c->reg);
640 	c->isen = 0;
641 	spin_unlock_irqrestore(c->reglock, flags);
642 }
643 
alchemy_clk_fgv2_setp(struct clk_hw * hw,u8 index)644 static int alchemy_clk_fgv2_setp(struct clk_hw *hw, u8 index)
645 {
646 	struct alchemy_fgcs_clk *c = to_fgcs_clk(hw);
647 	unsigned long flags;
648 
649 	spin_lock_irqsave(c->reglock, flags);
650 	c->parent = index + 1;	/* value to write to register */
651 	if (c->isen)
652 		__alchemy_clk_fgv2_en(c);
653 	spin_unlock_irqrestore(c->reglock, flags);
654 
655 	return 0;
656 }
657 
alchemy_clk_fgv2_getp(struct clk_hw * hw)658 static u8 alchemy_clk_fgv2_getp(struct clk_hw *hw)
659 {
660 	struct alchemy_fgcs_clk *c = to_fgcs_clk(hw);
661 	unsigned long flags, v;
662 
663 	spin_lock_irqsave(c->reglock, flags);
664 	v = c->parent - 1;
665 	spin_unlock_irqrestore(c->reglock, flags);
666 	return v;
667 }
668 
669 /* fg0-2 and fg4-6 share a "scale"-bit. With this bit cleared, the
670  * dividers behave exactly as on previous models (dividers are multiples
671  * of 2); with the bit set, dividers are multiples of 1, halving their
672  * range, but making them also much more flexible.
673  */
alchemy_clk_fgv2_setr(struct clk_hw * hw,unsigned long rate,unsigned long parent_rate)674 static int alchemy_clk_fgv2_setr(struct clk_hw *hw, unsigned long rate,
675 				 unsigned long parent_rate)
676 {
677 	struct alchemy_fgcs_clk *c = to_fgcs_clk(hw);
678 	int sh = c->shift + 2;
679 	unsigned long div, v, flags, ret;
680 
681 	if (!rate || !parent_rate || rate > parent_rate)
682 		return -EINVAL;
683 
684 	v = alchemy_rdsys(c->reg) & (1 << 30); /* test "scale" bit */
685 	ret = alchemy_calc_div(rate, parent_rate, v ? 1 : 2,
686 			       v ? 256 : 512, &div);
687 
688 	spin_lock_irqsave(c->reglock, flags);
689 	v = alchemy_rdsys(c->reg);
690 	v &= ~(0xff << sh);
691 	v |= (div & 0xff) << sh;
692 	alchemy_wrsys(v, c->reg);
693 	spin_unlock_irqrestore(c->reglock, flags);
694 
695 	return 0;
696 }
697 
alchemy_clk_fgv2_recalc(struct clk_hw * hw,unsigned long parent_rate)698 static unsigned long alchemy_clk_fgv2_recalc(struct clk_hw *hw,
699 					     unsigned long parent_rate)
700 {
701 	struct alchemy_fgcs_clk *c = to_fgcs_clk(hw);
702 	int sh = c->shift + 2;
703 	unsigned long v, t;
704 
705 	v = alchemy_rdsys(c->reg);
706 	t = parent_rate / (((v >> sh) & 0xff) + 1);
707 	if ((v & (1 << 30)) == 0)		/* test scale bit */
708 		t /= 2;
709 
710 	return t;
711 }
712 
alchemy_clk_fgv2_detr(struct clk_hw * hw,struct clk_rate_request * req)713 static int alchemy_clk_fgv2_detr(struct clk_hw *hw,
714 				 struct clk_rate_request *req)
715 {
716 	struct alchemy_fgcs_clk *c = to_fgcs_clk(hw);
717 	int scale, maxdiv;
718 
719 	if (alchemy_rdsys(c->reg) & (1 << 30)) {
720 		scale = 1;
721 		maxdiv = 256;
722 	} else {
723 		scale = 2;
724 		maxdiv = 512;
725 	}
726 
727 	return alchemy_clk_fgcs_detr(hw, req, scale, maxdiv);
728 }
729 
730 /* Au1300 larger input mux, no separate disable bit, flexible divider */
731 static const struct clk_ops alchemy_clkops_fgenv2 = {
732 	.recalc_rate	= alchemy_clk_fgv2_recalc,
733 	.determine_rate	= alchemy_clk_fgv2_detr,
734 	.set_rate	= alchemy_clk_fgv2_setr,
735 	.set_parent	= alchemy_clk_fgv2_setp,
736 	.get_parent	= alchemy_clk_fgv2_getp,
737 	.enable		= alchemy_clk_fgv2_en,
738 	.disable	= alchemy_clk_fgv2_dis,
739 	.is_enabled	= alchemy_clk_fgv2_isen,
740 };
741 
742 static const char * const alchemy_clk_fgv1_parents[] = {
743 	ALCHEMY_CPU_CLK, ALCHEMY_AUXPLL_CLK
744 };
745 
746 static const char * const alchemy_clk_fgv2_parents[] = {
747 	ALCHEMY_AUXPLL2_CLK, ALCHEMY_CPU_CLK, ALCHEMY_AUXPLL_CLK
748 };
749 
750 static const char * const alchemy_clk_fgen_names[] = {
751 	ALCHEMY_FG0_CLK, ALCHEMY_FG1_CLK, ALCHEMY_FG2_CLK,
752 	ALCHEMY_FG3_CLK, ALCHEMY_FG4_CLK, ALCHEMY_FG5_CLK };
753 
alchemy_clk_init_fgens(int ctype)754 static int __init alchemy_clk_init_fgens(int ctype)
755 {
756 	struct clk *c;
757 	struct clk_init_data id;
758 	struct alchemy_fgcs_clk *a;
759 	unsigned long v;
760 	int i, ret;
761 
762 	switch (ctype) {
763 	case ALCHEMY_CPU_AU1000...ALCHEMY_CPU_AU1200:
764 		id.ops = &alchemy_clkops_fgenv1;
765 		id.parent_names = alchemy_clk_fgv1_parents;
766 		id.num_parents = 2;
767 		break;
768 	case ALCHEMY_CPU_AU1300:
769 		id.ops = &alchemy_clkops_fgenv2;
770 		id.parent_names = alchemy_clk_fgv2_parents;
771 		id.num_parents = 3;
772 		break;
773 	default:
774 		return -ENODEV;
775 	}
776 	id.flags = CLK_SET_RATE_PARENT | CLK_GET_RATE_NOCACHE;
777 
778 	a = kcalloc(6, sizeof(*a), GFP_KERNEL);
779 	if (!a)
780 		return -ENOMEM;
781 
782 	spin_lock_init(&alchemy_clk_fg0_lock);
783 	spin_lock_init(&alchemy_clk_fg1_lock);
784 	ret = 0;
785 	for (i = 0; i < 6; i++) {
786 		id.name = alchemy_clk_fgen_names[i];
787 		a->shift = 10 * (i < 3 ? i : i - 3);
788 		if (i > 2) {
789 			a->reg = AU1000_SYS_FREQCTRL1;
790 			a->reglock = &alchemy_clk_fg1_lock;
791 		} else {
792 			a->reg = AU1000_SYS_FREQCTRL0;
793 			a->reglock = &alchemy_clk_fg0_lock;
794 		}
795 
796 		/* default to first parent if bootloader has set
797 		 * the mux to disabled state.
798 		 */
799 		if (ctype == ALCHEMY_CPU_AU1300) {
800 			v = alchemy_rdsys(a->reg);
801 			a->parent = (v >> a->shift) & 3;
802 			if (!a->parent) {
803 				a->parent = 1;
804 				a->isen = 0;
805 			} else
806 				a->isen = 1;
807 		}
808 
809 		a->hw.init = &id;
810 		c = clk_register(NULL, &a->hw);
811 		if (IS_ERR(c))
812 			ret++;
813 		else
814 			clk_register_clkdev(c, id.name, NULL);
815 		a++;
816 	}
817 
818 	return ret;
819 }
820 
821 /* internal sources muxes *********************************************/
822 
alchemy_clk_csrc_isen(struct clk_hw * hw)823 static int alchemy_clk_csrc_isen(struct clk_hw *hw)
824 {
825 	struct alchemy_fgcs_clk *c = to_fgcs_clk(hw);
826 	unsigned long v = alchemy_rdsys(c->reg);
827 
828 	return (((v >> c->shift) >> 2) & 7) != 0;
829 }
830 
__alchemy_clk_csrc_en(struct alchemy_fgcs_clk * c)831 static void __alchemy_clk_csrc_en(struct alchemy_fgcs_clk *c)
832 {
833 	unsigned long v = alchemy_rdsys(c->reg);
834 
835 	v &= ~((7 << 2) << c->shift);
836 	v |= ((c->parent & 7) << 2) << c->shift;
837 	alchemy_wrsys(v, c->reg);
838 	c->isen = 1;
839 }
840 
alchemy_clk_csrc_en(struct clk_hw * hw)841 static int alchemy_clk_csrc_en(struct clk_hw *hw)
842 {
843 	struct alchemy_fgcs_clk *c = to_fgcs_clk(hw);
844 	unsigned long flags;
845 
846 	/* enable by setting the previous parent clock */
847 	spin_lock_irqsave(c->reglock, flags);
848 	__alchemy_clk_csrc_en(c);
849 	spin_unlock_irqrestore(c->reglock, flags);
850 
851 	return 0;
852 }
853 
alchemy_clk_csrc_dis(struct clk_hw * hw)854 static void alchemy_clk_csrc_dis(struct clk_hw *hw)
855 {
856 	struct alchemy_fgcs_clk *c = to_fgcs_clk(hw);
857 	unsigned long v, flags;
858 
859 	spin_lock_irqsave(c->reglock, flags);
860 	v = alchemy_rdsys(c->reg);
861 	v &= ~((3 << 2) << c->shift);	/* mux to "disabled" state */
862 	alchemy_wrsys(v, c->reg);
863 	c->isen = 0;
864 	spin_unlock_irqrestore(c->reglock, flags);
865 }
866 
alchemy_clk_csrc_setp(struct clk_hw * hw,u8 index)867 static int alchemy_clk_csrc_setp(struct clk_hw *hw, u8 index)
868 {
869 	struct alchemy_fgcs_clk *c = to_fgcs_clk(hw);
870 	unsigned long flags;
871 
872 	spin_lock_irqsave(c->reglock, flags);
873 	c->parent = index + 1;	/* value to write to register */
874 	if (c->isen)
875 		__alchemy_clk_csrc_en(c);
876 	spin_unlock_irqrestore(c->reglock, flags);
877 
878 	return 0;
879 }
880 
alchemy_clk_csrc_getp(struct clk_hw * hw)881 static u8 alchemy_clk_csrc_getp(struct clk_hw *hw)
882 {
883 	struct alchemy_fgcs_clk *c = to_fgcs_clk(hw);
884 
885 	return c->parent - 1;
886 }
887 
alchemy_clk_csrc_recalc(struct clk_hw * hw,unsigned long parent_rate)888 static unsigned long alchemy_clk_csrc_recalc(struct clk_hw *hw,
889 					     unsigned long parent_rate)
890 {
891 	struct alchemy_fgcs_clk *c = to_fgcs_clk(hw);
892 	unsigned long v = (alchemy_rdsys(c->reg) >> c->shift) & 3;
893 
894 	return parent_rate / c->dt[v];
895 }
896 
alchemy_clk_csrc_setr(struct clk_hw * hw,unsigned long rate,unsigned long parent_rate)897 static int alchemy_clk_csrc_setr(struct clk_hw *hw, unsigned long rate,
898 				 unsigned long parent_rate)
899 {
900 	struct alchemy_fgcs_clk *c = to_fgcs_clk(hw);
901 	unsigned long d, v, flags;
902 	int i;
903 
904 	if (!rate || !parent_rate || rate > parent_rate)
905 		return -EINVAL;
906 
907 	d = (parent_rate + (rate / 2)) / rate;
908 	if (d > 4)
909 		return -EINVAL;
910 	if ((d == 3) && (c->dt[2] != 3))
911 		d = 4;
912 
913 	for (i = 0; i < 4; i++)
914 		if (c->dt[i] == d)
915 			break;
916 
917 	if (i >= 4)
918 		return -EINVAL;	/* oops */
919 
920 	spin_lock_irqsave(c->reglock, flags);
921 	v = alchemy_rdsys(c->reg);
922 	v &= ~(3 << c->shift);
923 	v |= (i & 3) << c->shift;
924 	alchemy_wrsys(v, c->reg);
925 	spin_unlock_irqrestore(c->reglock, flags);
926 
927 	return 0;
928 }
929 
alchemy_clk_csrc_detr(struct clk_hw * hw,struct clk_rate_request * req)930 static int alchemy_clk_csrc_detr(struct clk_hw *hw,
931 				 struct clk_rate_request *req)
932 {
933 	struct alchemy_fgcs_clk *c = to_fgcs_clk(hw);
934 	int scale = c->dt[2] == 3 ? 1 : 2; /* au1300 check */
935 
936 	return alchemy_clk_fgcs_detr(hw, req, scale, 4);
937 }
938 
939 static const struct clk_ops alchemy_clkops_csrc = {
940 	.recalc_rate	= alchemy_clk_csrc_recalc,
941 	.determine_rate	= alchemy_clk_csrc_detr,
942 	.set_rate	= alchemy_clk_csrc_setr,
943 	.set_parent	= alchemy_clk_csrc_setp,
944 	.get_parent	= alchemy_clk_csrc_getp,
945 	.enable		= alchemy_clk_csrc_en,
946 	.disable	= alchemy_clk_csrc_dis,
947 	.is_enabled	= alchemy_clk_csrc_isen,
948 };
949 
950 static const char * const alchemy_clk_csrc_parents[] = {
951 	/* disabled at index 0 */ ALCHEMY_AUXPLL_CLK,
952 	ALCHEMY_FG0_CLK, ALCHEMY_FG1_CLK, ALCHEMY_FG2_CLK,
953 	ALCHEMY_FG3_CLK, ALCHEMY_FG4_CLK, ALCHEMY_FG5_CLK
954 };
955 
956 /* divider tables */
957 static int alchemy_csrc_dt1[] = { 1, 4, 1, 2 };	/* rest */
958 static int alchemy_csrc_dt2[] = { 1, 4, 3, 2 };	/* Au1300 */
959 
alchemy_clk_setup_imux(int ctype)960 static int __init alchemy_clk_setup_imux(int ctype)
961 {
962 	struct alchemy_fgcs_clk *a;
963 	const char * const *names;
964 	struct clk_init_data id;
965 	unsigned long v;
966 	int i, ret, *dt;
967 	struct clk *c;
968 
969 	id.ops = &alchemy_clkops_csrc;
970 	id.parent_names = alchemy_clk_csrc_parents;
971 	id.num_parents = 7;
972 	id.flags = CLK_SET_RATE_PARENT | CLK_GET_RATE_NOCACHE;
973 
974 	dt = alchemy_csrc_dt1;
975 	switch (ctype) {
976 	case ALCHEMY_CPU_AU1000:
977 		names = alchemy_au1000_intclknames;
978 		break;
979 	case ALCHEMY_CPU_AU1500:
980 		names = alchemy_au1500_intclknames;
981 		break;
982 	case ALCHEMY_CPU_AU1100:
983 		names = alchemy_au1100_intclknames;
984 		break;
985 	case ALCHEMY_CPU_AU1550:
986 		names = alchemy_au1550_intclknames;
987 		break;
988 	case ALCHEMY_CPU_AU1200:
989 		names = alchemy_au1200_intclknames;
990 		break;
991 	case ALCHEMY_CPU_AU1300:
992 		dt = alchemy_csrc_dt2;
993 		names = alchemy_au1300_intclknames;
994 		break;
995 	default:
996 		return -ENODEV;
997 	}
998 
999 	a = kcalloc(6, sizeof(*a), GFP_KERNEL);
1000 	if (!a)
1001 		return -ENOMEM;
1002 
1003 	ret = 0;
1004 
1005 	for (i = 0; i < 6; i++) {
1006 		id.name = names[i];
1007 		if (!id.name)
1008 			goto next;
1009 
1010 		a->shift = i * 5;
1011 		a->reg = AU1000_SYS_CLKSRC;
1012 		a->reglock = &alchemy_clk_csrc_lock;
1013 		a->dt = dt;
1014 
1015 		/* default to first parent clock if mux is initially
1016 		 * set to disabled state.
1017 		 */
1018 		v = alchemy_rdsys(a->reg);
1019 		a->parent = ((v >> a->shift) >> 2) & 7;
1020 		if (!a->parent) {
1021 			a->parent = 1;
1022 			a->isen = 0;
1023 		} else
1024 			a->isen = 1;
1025 
1026 		a->hw.init = &id;
1027 		c = clk_register(NULL, &a->hw);
1028 		if (IS_ERR(c))
1029 			ret++;
1030 		else
1031 			clk_register_clkdev(c, id.name, NULL);
1032 next:
1033 		a++;
1034 	}
1035 
1036 	return ret;
1037 }
1038 
1039 
1040 /**********************************************************************/
1041 
1042 
1043 #define ERRCK(x)						\
1044 	if (IS_ERR(x)) {					\
1045 		ret = PTR_ERR(x);				\
1046 		goto out;					\
1047 	}
1048 
alchemy_clk_init(void)1049 static int __init alchemy_clk_init(void)
1050 {
1051 	int ctype = alchemy_get_cputype(), ret, i;
1052 	struct clk_aliastable *t = alchemy_clk_aliases;
1053 	struct clk *c;
1054 
1055 	/* Root of the Alchemy clock tree: external 12MHz crystal osc */
1056 	c = clk_register_fixed_rate(NULL, ALCHEMY_ROOT_CLK, NULL,
1057 					   0, ALCHEMY_ROOTCLK_RATE);
1058 	ERRCK(c)
1059 
1060 	/* CPU core clock */
1061 	c = alchemy_clk_setup_cpu(ALCHEMY_ROOT_CLK, ctype);
1062 	ERRCK(c)
1063 
1064 	/* AUXPLLs: max 1GHz on Au1300, 748MHz on older models */
1065 	i = (ctype == ALCHEMY_CPU_AU1300) ? 84 : 63;
1066 	c = alchemy_clk_setup_aux(ALCHEMY_ROOT_CLK, ALCHEMY_AUXPLL_CLK,
1067 				  i, AU1000_SYS_AUXPLL);
1068 	ERRCK(c)
1069 
1070 	if (ctype == ALCHEMY_CPU_AU1300) {
1071 		c = alchemy_clk_setup_aux(ALCHEMY_ROOT_CLK,
1072 					  ALCHEMY_AUXPLL2_CLK, i,
1073 					  AU1300_SYS_AUXPLL2);
1074 		ERRCK(c)
1075 	}
1076 
1077 	/* sysbus clock: cpu core clock divided by 2, 3 or 4 */
1078 	c = alchemy_clk_setup_sysbus(ALCHEMY_CPU_CLK);
1079 	ERRCK(c)
1080 
1081 	/* peripheral clock: runs at half rate of sysbus clk */
1082 	c = alchemy_clk_setup_periph(ALCHEMY_SYSBUS_CLK);
1083 	ERRCK(c)
1084 
1085 	/* SDR/DDR memory clock */
1086 	c = alchemy_clk_setup_mem(ALCHEMY_SYSBUS_CLK, ctype);
1087 	ERRCK(c)
1088 
1089 	/* L/RCLK: external static bus clock for synchronous mode */
1090 	c = alchemy_clk_setup_lrclk(ALCHEMY_PERIPH_CLK, ctype);
1091 	ERRCK(c)
1092 
1093 	/* Frequency dividers 0-5 */
1094 	ret = alchemy_clk_init_fgens(ctype);
1095 	if (ret) {
1096 		ret = -ENODEV;
1097 		goto out;
1098 	}
1099 
1100 	/* diving muxes for internal sources */
1101 	ret = alchemy_clk_setup_imux(ctype);
1102 	if (ret) {
1103 		ret = -ENODEV;
1104 		goto out;
1105 	}
1106 
1107 	/* set up aliases drivers might look for */
1108 	while (t->base) {
1109 		if (t->cputype == ctype)
1110 			clk_add_alias(t->alias, NULL, t->base, NULL);
1111 		t++;
1112 	}
1113 
1114 	pr_info("Alchemy clocktree installed\n");
1115 	return 0;
1116 
1117 out:
1118 	return ret;
1119 }
1120 postcore_initcall(alchemy_clk_init);
1121