xref: /linux/drivers/clk/clk-xgene.c (revision e814f3fd16acfb7f9966773953de8f740a1e3202)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  * clk-xgene.c - AppliedMicro X-Gene Clock Interface
4  *
5  * Copyright (c) 2013, Applied Micro Circuits Corporation
6  * Author: Loc Ho <lho@apm.com>
7  */
8 #include <linux/module.h>
9 #include <linux/spinlock.h>
10 #include <linux/string_choices.h>
11 #include <linux/io.h>
12 #include <linux/of.h>
13 #include <linux/clkdev.h>
14 #include <linux/clk-provider.h>
15 #include <linux/of_address.h>
16 
17 /* Register SCU_PCPPLL bit fields */
18 #define N_DIV_RD(src)			((src) & 0x000001ff)
19 #define SC_N_DIV_RD(src)		((src) & 0x0000007f)
20 #define SC_OUTDIV2(src)			(((src) & 0x00000100) >> 8)
21 
22 /* Register SCU_SOCPLL bit fields */
23 #define CLKR_RD(src)			(((src) & 0x07000000)>>24)
24 #define CLKOD_RD(src)			(((src) & 0x00300000)>>20)
25 #define REGSPEC_RESET_F1_MASK		0x00010000
26 #define CLKF_RD(src)			(((src) & 0x000001ff))
27 
28 #define XGENE_CLK_DRIVER_VER		"0.1"
29 
30 static DEFINE_SPINLOCK(clk_lock);
31 
32 static inline u32 xgene_clk_read(void __iomem *csr)
33 {
34 	return readl_relaxed(csr);
35 }
36 
37 static inline void xgene_clk_write(u32 data, void __iomem *csr)
38 {
39 	writel_relaxed(data, csr);
40 }
41 
42 /* PLL Clock */
43 enum xgene_pll_type {
44 	PLL_TYPE_PCP = 0,
45 	PLL_TYPE_SOC = 1,
46 };
47 
48 struct xgene_clk_pll {
49 	struct clk_hw	hw;
50 	void __iomem	*reg;
51 	spinlock_t	*lock;
52 	u32		pll_offset;
53 	enum xgene_pll_type	type;
54 	int		version;
55 };
56 
57 #define to_xgene_clk_pll(_hw) container_of(_hw, struct xgene_clk_pll, hw)
58 
59 static int xgene_clk_pll_is_enabled(struct clk_hw *hw)
60 {
61 	struct xgene_clk_pll *pllclk = to_xgene_clk_pll(hw);
62 	u32 data;
63 
64 	data = xgene_clk_read(pllclk->reg + pllclk->pll_offset);
65 	pr_debug("%s pll %s\n", clk_hw_get_name(hw),
66 		data & REGSPEC_RESET_F1_MASK ? "disabled" : "enabled");
67 
68 	return data & REGSPEC_RESET_F1_MASK ? 0 : 1;
69 }
70 
71 static unsigned long xgene_clk_pll_recalc_rate(struct clk_hw *hw,
72 				unsigned long parent_rate)
73 {
74 	struct xgene_clk_pll *pllclk = to_xgene_clk_pll(hw);
75 	unsigned long fref;
76 	unsigned long fvco;
77 	u32 pll;
78 	u32 nref;
79 	u32 nout;
80 	u32 nfb;
81 
82 	pll = xgene_clk_read(pllclk->reg + pllclk->pll_offset);
83 
84 	if (pllclk->version <= 1) {
85 		if (pllclk->type == PLL_TYPE_PCP) {
86 			/*
87 			* PLL VCO = Reference clock * NF
88 			* PCP PLL = PLL_VCO / 2
89 			*/
90 			nout = 2;
91 			fvco = parent_rate * (N_DIV_RD(pll) + 4);
92 		} else {
93 			/*
94 			* Fref = Reference Clock / NREF;
95 			* Fvco = Fref * NFB;
96 			* Fout = Fvco / NOUT;
97 			*/
98 			nref = CLKR_RD(pll) + 1;
99 			nout = CLKOD_RD(pll) + 1;
100 			nfb = CLKF_RD(pll);
101 			fref = parent_rate / nref;
102 			fvco = fref * nfb;
103 		}
104 	} else {
105 		/*
106 		 * fvco = Reference clock * FBDIVC
107 		 * PLL freq = fvco / NOUT
108 		 */
109 		nout = SC_OUTDIV2(pll) ? 2 : 3;
110 		fvco = parent_rate * SC_N_DIV_RD(pll);
111 	}
112 	pr_debug("%s pll recalc rate %ld parent %ld version %d\n",
113 		 clk_hw_get_name(hw), fvco / nout, parent_rate,
114 		 pllclk->version);
115 
116 	return fvco / nout;
117 }
118 
119 static const struct clk_ops xgene_clk_pll_ops = {
120 	.is_enabled = xgene_clk_pll_is_enabled,
121 	.recalc_rate = xgene_clk_pll_recalc_rate,
122 };
123 
124 static struct clk *xgene_register_clk_pll(struct device *dev,
125 	const char *name, const char *parent_name,
126 	unsigned long flags, void __iomem *reg, u32 pll_offset,
127 	u32 type, spinlock_t *lock, int version)
128 {
129 	struct xgene_clk_pll *apmclk;
130 	struct clk *clk;
131 	struct clk_init_data init;
132 
133 	/* allocate the APM clock structure */
134 	apmclk = kzalloc(sizeof(*apmclk), GFP_KERNEL);
135 	if (!apmclk)
136 		return ERR_PTR(-ENOMEM);
137 
138 	init.name = name;
139 	init.ops = &xgene_clk_pll_ops;
140 	init.flags = flags;
141 	init.parent_names = parent_name ? &parent_name : NULL;
142 	init.num_parents = parent_name ? 1 : 0;
143 
144 	apmclk->version = version;
145 	apmclk->reg = reg;
146 	apmclk->lock = lock;
147 	apmclk->pll_offset = pll_offset;
148 	apmclk->type = type;
149 	apmclk->hw.init = &init;
150 
151 	/* Register the clock */
152 	clk = clk_register(dev, &apmclk->hw);
153 	if (IS_ERR(clk)) {
154 		pr_err("%s: could not register clk %s\n", __func__, name);
155 		kfree(apmclk);
156 		return NULL;
157 	}
158 	return clk;
159 }
160 
161 static int xgene_pllclk_version(struct device_node *np)
162 {
163 	if (of_device_is_compatible(np, "apm,xgene-socpll-clock"))
164 		return 1;
165 	if (of_device_is_compatible(np, "apm,xgene-pcppll-clock"))
166 		return 1;
167 	return 2;
168 }
169 
170 static void xgene_pllclk_init(struct device_node *np, enum xgene_pll_type pll_type)
171 {
172 	const char *clk_name = np->full_name;
173 	struct clk *clk;
174 	void __iomem *reg;
175 	int version = xgene_pllclk_version(np);
176 
177 	reg = of_iomap(np, 0);
178 	if (!reg) {
179 		pr_err("Unable to map CSR register for %pOF\n", np);
180 		return;
181 	}
182 	of_property_read_string(np, "clock-output-names", &clk_name);
183 	clk = xgene_register_clk_pll(NULL,
184 			clk_name, of_clk_get_parent_name(np, 0),
185 			0, reg, 0, pll_type, &clk_lock,
186 			version);
187 	if (!IS_ERR(clk)) {
188 		of_clk_add_provider(np, of_clk_src_simple_get, clk);
189 		clk_register_clkdev(clk, clk_name, NULL);
190 		pr_debug("Add %s clock PLL\n", clk_name);
191 	}
192 }
193 
194 static void xgene_socpllclk_init(struct device_node *np)
195 {
196 	xgene_pllclk_init(np, PLL_TYPE_SOC);
197 }
198 
199 static void xgene_pcppllclk_init(struct device_node *np)
200 {
201 	xgene_pllclk_init(np, PLL_TYPE_PCP);
202 }
203 
204 /**
205  * struct xgene_clk_pmd - PMD clock
206  *
207  * @hw:		handle between common and hardware-specific interfaces
208  * @reg:	register containing the fractional scale multiplier (scaler)
209  * @shift:	shift to the unit bit field
210  * @mask:	mask to the unit bit field
211  * @denom:	1/denominator unit
212  * @lock:	register lock
213  * @flags: XGENE_CLK_PMD_SCALE_INVERTED - By default the scaler is the value read
214  *	from the register plus one. For example,
215  *		0 for (0 + 1) / denom,
216  *		1 for (1 + 1) / denom and etc.
217  *	If this flag is set, it is
218  *		0 for (denom - 0) / denom,
219  *		1 for (denom - 1) / denom and etc.
220  */
221 struct xgene_clk_pmd {
222 	struct clk_hw	hw;
223 	void __iomem	*reg;
224 	u8		shift;
225 	u32		mask;
226 	u64		denom;
227 	u32		flags;
228 	spinlock_t	*lock;
229 };
230 
231 #define to_xgene_clk_pmd(_hw) container_of(_hw, struct xgene_clk_pmd, hw)
232 
233 #define XGENE_CLK_PMD_SCALE_INVERTED	BIT(0)
234 #define XGENE_CLK_PMD_SHIFT		8
235 #define XGENE_CLK_PMD_WIDTH		3
236 
237 static unsigned long xgene_clk_pmd_recalc_rate(struct clk_hw *hw,
238 					       unsigned long parent_rate)
239 {
240 	struct xgene_clk_pmd *fd = to_xgene_clk_pmd(hw);
241 	unsigned long flags = 0;
242 	u64 ret, scale;
243 	u32 val;
244 
245 	if (fd->lock)
246 		spin_lock_irqsave(fd->lock, flags);
247 	else
248 		__acquire(fd->lock);
249 
250 	val = readl(fd->reg);
251 
252 	if (fd->lock)
253 		spin_unlock_irqrestore(fd->lock, flags);
254 	else
255 		__release(fd->lock);
256 
257 	ret = (u64)parent_rate;
258 
259 	scale = (val & fd->mask) >> fd->shift;
260 	if (fd->flags & XGENE_CLK_PMD_SCALE_INVERTED)
261 		scale = fd->denom - scale;
262 	else
263 		scale++;
264 
265 	/* freq = parent_rate * scaler / denom */
266 	do_div(ret, fd->denom);
267 	ret *= scale;
268 	if (ret == 0)
269 		ret = (u64)parent_rate;
270 
271 	return ret;
272 }
273 
274 static long xgene_clk_pmd_round_rate(struct clk_hw *hw, unsigned long rate,
275 				     unsigned long *parent_rate)
276 {
277 	struct xgene_clk_pmd *fd = to_xgene_clk_pmd(hw);
278 	u64 ret, scale;
279 
280 	if (!rate || rate >= *parent_rate)
281 		return *parent_rate;
282 
283 	/* freq = parent_rate * scaler / denom */
284 	ret = rate * fd->denom;
285 	scale = DIV_ROUND_UP_ULL(ret, *parent_rate);
286 
287 	ret = (u64)*parent_rate * scale;
288 	do_div(ret, fd->denom);
289 
290 	return ret;
291 }
292 
293 static int xgene_clk_pmd_set_rate(struct clk_hw *hw, unsigned long rate,
294 				  unsigned long parent_rate)
295 {
296 	struct xgene_clk_pmd *fd = to_xgene_clk_pmd(hw);
297 	unsigned long flags = 0;
298 	u64 scale, ret;
299 	u32 val;
300 
301 	/*
302 	 * Compute the scaler:
303 	 *
304 	 * freq = parent_rate * scaler / denom, or
305 	 * scaler = freq * denom / parent_rate
306 	 */
307 	ret = rate * fd->denom;
308 	scale = DIV_ROUND_UP_ULL(ret, (u64)parent_rate);
309 
310 	/* Check if inverted */
311 	if (fd->flags & XGENE_CLK_PMD_SCALE_INVERTED)
312 		scale = fd->denom - scale;
313 	else
314 		scale--;
315 
316 	if (fd->lock)
317 		spin_lock_irqsave(fd->lock, flags);
318 	else
319 		__acquire(fd->lock);
320 
321 	val = readl(fd->reg);
322 	val &= ~fd->mask;
323 	val |= (scale << fd->shift);
324 	writel(val, fd->reg);
325 
326 	if (fd->lock)
327 		spin_unlock_irqrestore(fd->lock, flags);
328 	else
329 		__release(fd->lock);
330 
331 	return 0;
332 }
333 
334 static const struct clk_ops xgene_clk_pmd_ops = {
335 	.recalc_rate = xgene_clk_pmd_recalc_rate,
336 	.round_rate = xgene_clk_pmd_round_rate,
337 	.set_rate = xgene_clk_pmd_set_rate,
338 };
339 
340 static struct clk *
341 xgene_register_clk_pmd(struct device *dev,
342 		       const char *name, const char *parent_name,
343 		       unsigned long flags, void __iomem *reg, u8 shift,
344 		       u8 width, u64 denom, u32 clk_flags, spinlock_t *lock)
345 {
346 	struct xgene_clk_pmd *fd;
347 	struct clk_init_data init;
348 	struct clk *clk;
349 
350 	fd = kzalloc(sizeof(*fd), GFP_KERNEL);
351 	if (!fd)
352 		return ERR_PTR(-ENOMEM);
353 
354 	init.name = name;
355 	init.ops = &xgene_clk_pmd_ops;
356 	init.flags = flags;
357 	init.parent_names = parent_name ? &parent_name : NULL;
358 	init.num_parents = parent_name ? 1 : 0;
359 
360 	fd->reg = reg;
361 	fd->shift = shift;
362 	fd->mask = (BIT(width) - 1) << shift;
363 	fd->denom = denom;
364 	fd->flags = clk_flags;
365 	fd->lock = lock;
366 	fd->hw.init = &init;
367 
368 	clk = clk_register(dev, &fd->hw);
369 	if (IS_ERR(clk)) {
370 		pr_err("%s: could not register clk %s\n", __func__, name);
371 		kfree(fd);
372 		return NULL;
373 	}
374 
375 	return clk;
376 }
377 
378 static void xgene_pmdclk_init(struct device_node *np)
379 {
380 	const char *clk_name = np->full_name;
381 	void __iomem *csr_reg;
382 	struct resource res;
383 	struct clk *clk;
384 	u64 denom;
385 	u32 flags = 0;
386 	int rc;
387 
388 	/* Check if the entry is disabled */
389 	if (!of_device_is_available(np))
390 		return;
391 
392 	/* Parse the DTS register for resource */
393 	rc = of_address_to_resource(np, 0, &res);
394 	if (rc != 0) {
395 		pr_err("no DTS register for %pOF\n", np);
396 		return;
397 	}
398 	csr_reg = of_iomap(np, 0);
399 	if (!csr_reg) {
400 		pr_err("Unable to map resource for %pOF\n", np);
401 		return;
402 	}
403 	of_property_read_string(np, "clock-output-names", &clk_name);
404 
405 	denom = BIT(XGENE_CLK_PMD_WIDTH);
406 	flags |= XGENE_CLK_PMD_SCALE_INVERTED;
407 
408 	clk = xgene_register_clk_pmd(NULL, clk_name,
409 				     of_clk_get_parent_name(np, 0), 0,
410 				     csr_reg, XGENE_CLK_PMD_SHIFT,
411 				     XGENE_CLK_PMD_WIDTH, denom,
412 				     flags, &clk_lock);
413 	if (!IS_ERR(clk)) {
414 		of_clk_add_provider(np, of_clk_src_simple_get, clk);
415 		clk_register_clkdev(clk, clk_name, NULL);
416 		pr_debug("Add %s clock\n", clk_name);
417 	} else {
418 		if (csr_reg)
419 			iounmap(csr_reg);
420 	}
421 }
422 
423 /* IP Clock */
424 struct xgene_dev_parameters {
425 	void __iomem *csr_reg;		/* CSR for IP clock */
426 	u32 reg_clk_offset;		/* Offset to clock enable CSR */
427 	u32 reg_clk_mask;		/* Mask bit for clock enable */
428 	u32 reg_csr_offset;		/* Offset to CSR reset */
429 	u32 reg_csr_mask;		/* Mask bit for disable CSR reset */
430 	void __iomem *divider_reg;	/* CSR for divider */
431 	u32 reg_divider_offset;		/* Offset to divider register */
432 	u32 reg_divider_shift;		/* Bit shift to divider field */
433 	u32 reg_divider_width;		/* Width of the bit to divider field */
434 };
435 
436 struct xgene_clk {
437 	struct clk_hw	hw;
438 	spinlock_t	*lock;
439 	struct xgene_dev_parameters	param;
440 };
441 
442 #define to_xgene_clk(_hw) container_of(_hw, struct xgene_clk, hw)
443 
444 static int xgene_clk_enable(struct clk_hw *hw)
445 {
446 	struct xgene_clk *pclk = to_xgene_clk(hw);
447 	unsigned long flags = 0;
448 	u32 data;
449 
450 	if (pclk->lock)
451 		spin_lock_irqsave(pclk->lock, flags);
452 
453 	if (pclk->param.csr_reg) {
454 		pr_debug("%s clock enabled\n", clk_hw_get_name(hw));
455 		/* First enable the clock */
456 		data = xgene_clk_read(pclk->param.csr_reg +
457 					pclk->param.reg_clk_offset);
458 		data |= pclk->param.reg_clk_mask;
459 		xgene_clk_write(data, pclk->param.csr_reg +
460 					pclk->param.reg_clk_offset);
461 		pr_debug("%s clk offset 0x%08X mask 0x%08X value 0x%08X\n",
462 			clk_hw_get_name(hw),
463 			pclk->param.reg_clk_offset, pclk->param.reg_clk_mask,
464 			data);
465 
466 		/* Second enable the CSR */
467 		data = xgene_clk_read(pclk->param.csr_reg +
468 					pclk->param.reg_csr_offset);
469 		data &= ~pclk->param.reg_csr_mask;
470 		xgene_clk_write(data, pclk->param.csr_reg +
471 					pclk->param.reg_csr_offset);
472 		pr_debug("%s csr offset 0x%08X mask 0x%08X value 0x%08X\n",
473 			clk_hw_get_name(hw),
474 			pclk->param.reg_csr_offset, pclk->param.reg_csr_mask,
475 			data);
476 	}
477 
478 	if (pclk->lock)
479 		spin_unlock_irqrestore(pclk->lock, flags);
480 
481 	return 0;
482 }
483 
484 static void xgene_clk_disable(struct clk_hw *hw)
485 {
486 	struct xgene_clk *pclk = to_xgene_clk(hw);
487 	unsigned long flags = 0;
488 	u32 data;
489 
490 	if (pclk->lock)
491 		spin_lock_irqsave(pclk->lock, flags);
492 
493 	if (pclk->param.csr_reg) {
494 		pr_debug("%s clock disabled\n", clk_hw_get_name(hw));
495 		/* First put the CSR in reset */
496 		data = xgene_clk_read(pclk->param.csr_reg +
497 					pclk->param.reg_csr_offset);
498 		data |= pclk->param.reg_csr_mask;
499 		xgene_clk_write(data, pclk->param.csr_reg +
500 					pclk->param.reg_csr_offset);
501 
502 		/* Second disable the clock */
503 		data = xgene_clk_read(pclk->param.csr_reg +
504 					pclk->param.reg_clk_offset);
505 		data &= ~pclk->param.reg_clk_mask;
506 		xgene_clk_write(data, pclk->param.csr_reg +
507 					pclk->param.reg_clk_offset);
508 	}
509 
510 	if (pclk->lock)
511 		spin_unlock_irqrestore(pclk->lock, flags);
512 }
513 
514 static int xgene_clk_is_enabled(struct clk_hw *hw)
515 {
516 	struct xgene_clk *pclk = to_xgene_clk(hw);
517 	u32 data = 0;
518 
519 	if (pclk->param.csr_reg) {
520 		pr_debug("%s clock checking\n", clk_hw_get_name(hw));
521 		data = xgene_clk_read(pclk->param.csr_reg +
522 					pclk->param.reg_clk_offset);
523 		pr_debug("%s clock is %s\n", clk_hw_get_name(hw),
524 			str_enabled_disabled(data & pclk->param.reg_clk_mask));
525 	} else {
526 		return 1;
527 	}
528 
529 	return data & pclk->param.reg_clk_mask ? 1 : 0;
530 }
531 
532 static unsigned long xgene_clk_recalc_rate(struct clk_hw *hw,
533 				unsigned long parent_rate)
534 {
535 	struct xgene_clk *pclk = to_xgene_clk(hw);
536 	u32 data;
537 
538 	if (pclk->param.divider_reg) {
539 		data = xgene_clk_read(pclk->param.divider_reg +
540 					pclk->param.reg_divider_offset);
541 		data >>= pclk->param.reg_divider_shift;
542 		data &= (1 << pclk->param.reg_divider_width) - 1;
543 
544 		pr_debug("%s clock recalc rate %ld parent %ld\n",
545 			clk_hw_get_name(hw),
546 			parent_rate / data, parent_rate);
547 
548 		return parent_rate / data;
549 	} else {
550 		pr_debug("%s clock recalc rate %ld parent %ld\n",
551 			clk_hw_get_name(hw), parent_rate, parent_rate);
552 		return parent_rate;
553 	}
554 }
555 
556 static int xgene_clk_set_rate(struct clk_hw *hw, unsigned long rate,
557 				unsigned long parent_rate)
558 {
559 	struct xgene_clk *pclk = to_xgene_clk(hw);
560 	unsigned long flags = 0;
561 	u32 data;
562 	u32 divider;
563 	u32 divider_save;
564 
565 	if (pclk->lock)
566 		spin_lock_irqsave(pclk->lock, flags);
567 
568 	if (pclk->param.divider_reg) {
569 		/* Let's compute the divider */
570 		if (rate > parent_rate)
571 			rate = parent_rate;
572 		divider_save = divider = parent_rate / rate; /* Rounded down */
573 		divider &= (1 << pclk->param.reg_divider_width) - 1;
574 		divider <<= pclk->param.reg_divider_shift;
575 
576 		/* Set new divider */
577 		data = xgene_clk_read(pclk->param.divider_reg +
578 				pclk->param.reg_divider_offset);
579 		data &= ~(((1 << pclk->param.reg_divider_width) - 1)
580 				<< pclk->param.reg_divider_shift);
581 		data |= divider;
582 		xgene_clk_write(data, pclk->param.divider_reg +
583 					pclk->param.reg_divider_offset);
584 		pr_debug("%s clock set rate %ld\n", clk_hw_get_name(hw),
585 			parent_rate / divider_save);
586 	} else {
587 		divider_save = 1;
588 	}
589 
590 	if (pclk->lock)
591 		spin_unlock_irqrestore(pclk->lock, flags);
592 
593 	return parent_rate / divider_save;
594 }
595 
596 static long xgene_clk_round_rate(struct clk_hw *hw, unsigned long rate,
597 				unsigned long *prate)
598 {
599 	struct xgene_clk *pclk = to_xgene_clk(hw);
600 	unsigned long parent_rate = *prate;
601 	u32 divider;
602 
603 	if (pclk->param.divider_reg) {
604 		/* Let's compute the divider */
605 		if (rate > parent_rate)
606 			rate = parent_rate;
607 		divider = parent_rate / rate;   /* Rounded down */
608 	} else {
609 		divider = 1;
610 	}
611 
612 	return parent_rate / divider;
613 }
614 
615 static const struct clk_ops xgene_clk_ops = {
616 	.enable = xgene_clk_enable,
617 	.disable = xgene_clk_disable,
618 	.is_enabled = xgene_clk_is_enabled,
619 	.recalc_rate = xgene_clk_recalc_rate,
620 	.set_rate = xgene_clk_set_rate,
621 	.round_rate = xgene_clk_round_rate,
622 };
623 
624 static struct clk *xgene_register_clk(struct device *dev,
625 		const char *name, const char *parent_name,
626 		struct xgene_dev_parameters *parameters, spinlock_t *lock)
627 {
628 	struct xgene_clk *apmclk;
629 	struct clk *clk;
630 	struct clk_init_data init;
631 	int rc;
632 
633 	/* allocate the APM clock structure */
634 	apmclk = kzalloc(sizeof(*apmclk), GFP_KERNEL);
635 	if (!apmclk)
636 		return ERR_PTR(-ENOMEM);
637 
638 	init.name = name;
639 	init.ops = &xgene_clk_ops;
640 	init.flags = 0;
641 	init.parent_names = parent_name ? &parent_name : NULL;
642 	init.num_parents = parent_name ? 1 : 0;
643 
644 	apmclk->lock = lock;
645 	apmclk->hw.init = &init;
646 	apmclk->param = *parameters;
647 
648 	/* Register the clock */
649 	clk = clk_register(dev, &apmclk->hw);
650 	if (IS_ERR(clk)) {
651 		pr_err("%s: could not register clk %s\n", __func__, name);
652 		kfree(apmclk);
653 		return clk;
654 	}
655 
656 	/* Register the clock for lookup */
657 	rc = clk_register_clkdev(clk, name, NULL);
658 	if (rc != 0) {
659 		pr_err("%s: could not register lookup clk %s\n",
660 			__func__, name);
661 	}
662 	return clk;
663 }
664 
665 static void __init xgene_devclk_init(struct device_node *np)
666 {
667 	const char *clk_name = np->full_name;
668 	struct clk *clk;
669 	struct resource res;
670 	int rc;
671 	struct xgene_dev_parameters parameters;
672 	int i;
673 
674 	/* Check if the entry is disabled */
675         if (!of_device_is_available(np))
676                 return;
677 
678 	/* Parse the DTS register for resource */
679 	parameters.csr_reg = NULL;
680 	parameters.divider_reg = NULL;
681 	for (i = 0; i < 2; i++) {
682 		void __iomem *map_res;
683 		rc = of_address_to_resource(np, i, &res);
684 		if (rc != 0) {
685 			if (i == 0) {
686 				pr_err("no DTS register for %pOF\n", np);
687 				return;
688 			}
689 			break;
690 		}
691 		map_res = of_iomap(np, i);
692 		if (!map_res) {
693 			pr_err("Unable to map resource %d for %pOF\n", i, np);
694 			goto err;
695 		}
696 		if (strcmp(res.name, "div-reg") == 0)
697 			parameters.divider_reg = map_res;
698 		else /* if (strcmp(res->name, "csr-reg") == 0) */
699 			parameters.csr_reg = map_res;
700 	}
701 	if (of_property_read_u32(np, "csr-offset", &parameters.reg_csr_offset))
702 		parameters.reg_csr_offset = 0;
703 	if (of_property_read_u32(np, "csr-mask", &parameters.reg_csr_mask))
704 		parameters.reg_csr_mask = 0xF;
705 	if (of_property_read_u32(np, "enable-offset",
706 				&parameters.reg_clk_offset))
707 		parameters.reg_clk_offset = 0x8;
708 	if (of_property_read_u32(np, "enable-mask", &parameters.reg_clk_mask))
709 		parameters.reg_clk_mask = 0xF;
710 	if (of_property_read_u32(np, "divider-offset",
711 				&parameters.reg_divider_offset))
712 		parameters.reg_divider_offset = 0;
713 	if (of_property_read_u32(np, "divider-width",
714 				&parameters.reg_divider_width))
715 		parameters.reg_divider_width = 0;
716 	if (of_property_read_u32(np, "divider-shift",
717 				&parameters.reg_divider_shift))
718 		parameters.reg_divider_shift = 0;
719 	of_property_read_string(np, "clock-output-names", &clk_name);
720 
721 	clk = xgene_register_clk(NULL, clk_name,
722 		of_clk_get_parent_name(np, 0), &parameters, &clk_lock);
723 	if (IS_ERR(clk))
724 		goto err;
725 	pr_debug("Add %s clock\n", clk_name);
726 	rc = of_clk_add_provider(np, of_clk_src_simple_get, clk);
727 	if (rc != 0)
728 		pr_err("%s: could register provider clk %pOF\n", __func__, np);
729 
730 	return;
731 
732 err:
733 	if (parameters.csr_reg)
734 		iounmap(parameters.csr_reg);
735 	if (parameters.divider_reg)
736 		iounmap(parameters.divider_reg);
737 }
738 
739 CLK_OF_DECLARE(xgene_socpll_clock, "apm,xgene-socpll-clock", xgene_socpllclk_init);
740 CLK_OF_DECLARE(xgene_pcppll_clock, "apm,xgene-pcppll-clock", xgene_pcppllclk_init);
741 CLK_OF_DECLARE(xgene_pmd_clock, "apm,xgene-pmd-clock", xgene_pmdclk_init);
742 CLK_OF_DECLARE(xgene_socpll_v2_clock, "apm,xgene-socpll-v2-clock",
743 	       xgene_socpllclk_init);
744 CLK_OF_DECLARE(xgene_pcppll_v2_clock, "apm,xgene-pcppll-v2-clock",
745 	       xgene_pcppllclk_init);
746 CLK_OF_DECLARE(xgene_dev_clock, "apm,xgene-device-clock", xgene_devclk_init);
747