xref: /kernel/linux/linux-5.10/drivers/clk/zte/clk.c (revision 8c2ecf20)
1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * Copyright 2014 Linaro Ltd.
4 * Copyright (C) 2014 ZTE Corporation.
5 */
6
7#include <linux/clk-provider.h>
8#include <linux/err.h>
9#include <linux/gcd.h>
10#include <linux/io.h>
11#include <linux/iopoll.h>
12#include <linux/slab.h>
13#include <linux/spinlock.h>
14#include <asm/div64.h>
15
16#include "clk.h"
17
18#define to_clk_zx_pll(_hw) container_of(_hw, struct clk_zx_pll, hw)
19#define to_clk_zx_audio(_hw) container_of(_hw, struct clk_zx_audio, hw)
20
21#define CFG0_CFG1_OFFSET 4
22#define LOCK_FLAG 30
23#define POWER_DOWN 31
24
25static int rate_to_idx(struct clk_zx_pll *zx_pll, unsigned long rate)
26{
27	const struct zx_pll_config *config = zx_pll->lookup_table;
28	int i;
29
30	for (i = 0; i < zx_pll->count; i++) {
31		if (config[i].rate > rate)
32			return i > 0 ? i - 1 : 0;
33
34		if (config[i].rate == rate)
35			return i;
36	}
37
38	return i - 1;
39}
40
41static int hw_to_idx(struct clk_zx_pll *zx_pll)
42{
43	const struct zx_pll_config *config = zx_pll->lookup_table;
44	u32 hw_cfg0, hw_cfg1;
45	int i;
46
47	hw_cfg0 = readl_relaxed(zx_pll->reg_base);
48	hw_cfg1 = readl_relaxed(zx_pll->reg_base + CFG0_CFG1_OFFSET);
49
50	/* For matching the value in lookup table */
51	hw_cfg0 &= ~BIT(zx_pll->lock_bit);
52
53	/* Check availability of pd_bit */
54	if (zx_pll->pd_bit < 32)
55		hw_cfg0 |= BIT(zx_pll->pd_bit);
56
57	for (i = 0; i < zx_pll->count; i++) {
58		if (hw_cfg0 == config[i].cfg0 && hw_cfg1 == config[i].cfg1)
59			return i;
60	}
61
62	return -EINVAL;
63}
64
65static unsigned long zx_pll_recalc_rate(struct clk_hw *hw,
66					unsigned long parent_rate)
67{
68	struct clk_zx_pll *zx_pll = to_clk_zx_pll(hw);
69	int idx;
70
71	idx = hw_to_idx(zx_pll);
72	if (unlikely(idx == -EINVAL))
73		return 0;
74
75	return zx_pll->lookup_table[idx].rate;
76}
77
78static long zx_pll_round_rate(struct clk_hw *hw, unsigned long rate,
79			      unsigned long *prate)
80{
81	struct clk_zx_pll *zx_pll = to_clk_zx_pll(hw);
82	int idx;
83
84	idx = rate_to_idx(zx_pll, rate);
85
86	return zx_pll->lookup_table[idx].rate;
87}
88
89static int zx_pll_set_rate(struct clk_hw *hw, unsigned long rate,
90			   unsigned long parent_rate)
91{
92	/* Assume current cpu is not running on current PLL */
93	struct clk_zx_pll *zx_pll = to_clk_zx_pll(hw);
94	const struct zx_pll_config *config;
95	int idx;
96
97	idx = rate_to_idx(zx_pll, rate);
98	config = &zx_pll->lookup_table[idx];
99
100	writel_relaxed(config->cfg0, zx_pll->reg_base);
101	writel_relaxed(config->cfg1, zx_pll->reg_base + CFG0_CFG1_OFFSET);
102
103	return 0;
104}
105
106static int zx_pll_enable(struct clk_hw *hw)
107{
108	struct clk_zx_pll *zx_pll = to_clk_zx_pll(hw);
109	u32 reg;
110
111	/* If pd_bit is not available, simply return success. */
112	if (zx_pll->pd_bit > 31)
113		return 0;
114
115	reg = readl_relaxed(zx_pll->reg_base);
116	writel_relaxed(reg & ~BIT(zx_pll->pd_bit), zx_pll->reg_base);
117
118	return readl_relaxed_poll_timeout(zx_pll->reg_base, reg,
119					  reg & BIT(zx_pll->lock_bit), 0, 100);
120}
121
122static void zx_pll_disable(struct clk_hw *hw)
123{
124	struct clk_zx_pll *zx_pll = to_clk_zx_pll(hw);
125	u32 reg;
126
127	if (zx_pll->pd_bit > 31)
128		return;
129
130	reg = readl_relaxed(zx_pll->reg_base);
131	writel_relaxed(reg | BIT(zx_pll->pd_bit), zx_pll->reg_base);
132}
133
134static int zx_pll_is_enabled(struct clk_hw *hw)
135{
136	struct clk_zx_pll *zx_pll = to_clk_zx_pll(hw);
137	u32 reg;
138
139	reg = readl_relaxed(zx_pll->reg_base);
140
141	return !(reg & BIT(zx_pll->pd_bit));
142}
143
144const struct clk_ops zx_pll_ops = {
145	.recalc_rate = zx_pll_recalc_rate,
146	.round_rate = zx_pll_round_rate,
147	.set_rate = zx_pll_set_rate,
148	.enable = zx_pll_enable,
149	.disable = zx_pll_disable,
150	.is_enabled = zx_pll_is_enabled,
151};
152EXPORT_SYMBOL(zx_pll_ops);
153
154struct clk *clk_register_zx_pll(const char *name, const char *parent_name,
155				unsigned long flags, void __iomem *reg_base,
156				const struct zx_pll_config *lookup_table,
157				int count, spinlock_t *lock)
158{
159	struct clk_zx_pll *zx_pll;
160	struct clk *clk;
161	struct clk_init_data init;
162
163	zx_pll = kzalloc(sizeof(*zx_pll), GFP_KERNEL);
164	if (!zx_pll)
165		return ERR_PTR(-ENOMEM);
166
167	init.name = name;
168	init.ops = &zx_pll_ops;
169	init.flags = flags;
170	init.parent_names = parent_name ? &parent_name : NULL;
171	init.num_parents = parent_name ? 1 : 0;
172
173	zx_pll->reg_base = reg_base;
174	zx_pll->lookup_table = lookup_table;
175	zx_pll->count = count;
176	zx_pll->lock_bit = LOCK_FLAG;
177	zx_pll->pd_bit = POWER_DOWN;
178	zx_pll->lock = lock;
179	zx_pll->hw.init = &init;
180
181	clk = clk_register(NULL, &zx_pll->hw);
182	if (IS_ERR(clk))
183		kfree(zx_pll);
184
185	return clk;
186}
187
188#define BPAR 1000000
189static u32 calc_reg(u32 parent_rate, u32 rate)
190{
191	u32 sel, integ, fra_div, tmp;
192	u64 tmp64 = (u64)parent_rate * BPAR;
193
194	do_div(tmp64, rate);
195	integ = (u32)tmp64 / BPAR;
196	integ = integ >> 1;
197
198	tmp = (u32)tmp64 % BPAR;
199	sel = tmp / BPAR;
200
201	tmp = tmp % BPAR;
202	fra_div = tmp * 0xff / BPAR;
203	tmp = (sel << 24) | (integ << 16) | (0xff << 8) | fra_div;
204
205	/* Set I2S integer divider as 1. This bit is reserved for SPDIF
206	 * and do no harm.
207	 */
208	tmp |= BIT(28);
209	return tmp;
210}
211
212static u32 calc_rate(u32 reg, u32 parent_rate)
213{
214	u32 sel, integ, fra_div, tmp;
215	u64 tmp64 = (u64)parent_rate * BPAR;
216
217	tmp = reg;
218	sel = (tmp >> 24) & BIT(0);
219	integ = (tmp >> 16) & 0xff;
220	fra_div = tmp & 0xff;
221
222	tmp = fra_div * BPAR;
223	tmp = tmp / 0xff;
224	tmp += sel * BPAR;
225	tmp += 2 * integ * BPAR;
226	do_div(tmp64, tmp);
227
228	return (u32)tmp64;
229}
230
231static unsigned long zx_audio_recalc_rate(struct clk_hw *hw,
232					  unsigned long parent_rate)
233{
234	struct clk_zx_audio *zx_audio = to_clk_zx_audio(hw);
235	u32 reg;
236
237	reg = readl_relaxed(zx_audio->reg_base);
238	return calc_rate(reg, parent_rate);
239}
240
241static long zx_audio_round_rate(struct clk_hw *hw, unsigned long rate,
242				unsigned long *prate)
243{
244	u32 reg;
245
246	if (rate * 2 > *prate)
247		return -EINVAL;
248
249	reg = calc_reg(*prate, rate);
250	return calc_rate(reg, *prate);
251}
252
253static int zx_audio_set_rate(struct clk_hw *hw, unsigned long rate,
254			     unsigned long parent_rate)
255{
256	struct clk_zx_audio *zx_audio = to_clk_zx_audio(hw);
257	u32 reg;
258
259	reg = calc_reg(parent_rate, rate);
260	writel_relaxed(reg, zx_audio->reg_base);
261
262	return 0;
263}
264
265#define ZX_AUDIO_EN BIT(25)
266static int zx_audio_enable(struct clk_hw *hw)
267{
268	struct clk_zx_audio *zx_audio = to_clk_zx_audio(hw);
269	u32 reg;
270
271	reg = readl_relaxed(zx_audio->reg_base);
272	writel_relaxed(reg & ~ZX_AUDIO_EN, zx_audio->reg_base);
273	return 0;
274}
275
276static void zx_audio_disable(struct clk_hw *hw)
277{
278	struct clk_zx_audio *zx_audio = to_clk_zx_audio(hw);
279	u32 reg;
280
281	reg = readl_relaxed(zx_audio->reg_base);
282	writel_relaxed(reg | ZX_AUDIO_EN, zx_audio->reg_base);
283}
284
285static const struct clk_ops zx_audio_ops = {
286	.recalc_rate = zx_audio_recalc_rate,
287	.round_rate = zx_audio_round_rate,
288	.set_rate = zx_audio_set_rate,
289	.enable = zx_audio_enable,
290	.disable = zx_audio_disable,
291};
292
293struct clk *clk_register_zx_audio(const char *name,
294				  const char * const parent_name,
295				  unsigned long flags,
296				  void __iomem *reg_base)
297{
298	struct clk_zx_audio *zx_audio;
299	struct clk *clk;
300	struct clk_init_data init;
301
302	zx_audio = kzalloc(sizeof(*zx_audio), GFP_KERNEL);
303	if (!zx_audio)
304		return ERR_PTR(-ENOMEM);
305
306	init.name = name;
307	init.ops = &zx_audio_ops;
308	init.flags = flags;
309	init.parent_names = parent_name ? &parent_name : NULL;
310	init.num_parents = parent_name ? 1 : 0;
311
312	zx_audio->reg_base = reg_base;
313	zx_audio->hw.init = &init;
314
315	clk = clk_register(NULL, &zx_audio->hw);
316	if (IS_ERR(clk))
317		kfree(zx_audio);
318
319	return clk;
320}
321
322#define CLK_AUDIO_DIV_FRAC	BIT(0)
323#define CLK_AUDIO_DIV_INT	BIT(1)
324#define CLK_AUDIO_DIV_UNCOMMON	BIT(1)
325
326#define CLK_AUDIO_DIV_FRAC_NSHIFT	16
327#define CLK_AUDIO_DIV_INT_FRAC_RE	BIT(16)
328#define CLK_AUDIO_DIV_INT_FRAC_MAX	(0xffff)
329#define CLK_AUDIO_DIV_INT_FRAC_MIN	(0x2)
330#define CLK_AUDIO_DIV_INT_INT_SHIFT	24
331#define CLK_AUDIO_DIV_INT_INT_WIDTH	4
332
333struct zx_clk_audio_div_table {
334	unsigned long rate;
335	unsigned int int_reg;
336	unsigned int frac_reg;
337};
338
339#define to_clk_zx_audio_div(_hw) container_of(_hw, struct clk_zx_audio_divider, hw)
340
341static unsigned long audio_calc_rate(struct clk_zx_audio_divider *audio_div,
342				     u32 reg_frac, u32 reg_int,
343				     unsigned long parent_rate)
344{
345	unsigned long rate, m, n;
346
347	m = reg_frac & 0xffff;
348	n = (reg_frac >> 16) & 0xffff;
349
350	m = (reg_int & 0xffff) * n + m;
351	rate = (parent_rate * n) / m;
352
353	return rate;
354}
355
356static void audio_calc_reg(struct clk_zx_audio_divider *audio_div,
357			   struct zx_clk_audio_div_table *div_table,
358			   unsigned long rate, unsigned long parent_rate)
359{
360	unsigned int reg_int, reg_frac;
361	unsigned long m, n, div;
362
363	reg_int = parent_rate / rate;
364
365	if (reg_int > CLK_AUDIO_DIV_INT_FRAC_MAX)
366		reg_int = CLK_AUDIO_DIV_INT_FRAC_MAX;
367	else if (reg_int < CLK_AUDIO_DIV_INT_FRAC_MIN)
368		reg_int = 0;
369	m = parent_rate - rate * reg_int;
370	n = rate;
371
372	div = gcd(m, n);
373	m = m / div;
374	n = n / div;
375
376	if ((m >> 16) || (n >> 16)) {
377		if (m > n) {
378			n = n * 0xffff / m;
379			m = 0xffff;
380		} else {
381			m = m * 0xffff / n;
382			n = 0xffff;
383		}
384	}
385	reg_frac = m | (n << 16);
386
387	div_table->rate = parent_rate * n / (reg_int * n + m);
388	div_table->int_reg = reg_int;
389	div_table->frac_reg = reg_frac;
390}
391
392static unsigned long zx_audio_div_recalc_rate(struct clk_hw *hw,
393					  unsigned long parent_rate)
394{
395	struct clk_zx_audio_divider *zx_audio_div = to_clk_zx_audio_div(hw);
396	u32 reg_frac, reg_int;
397
398	reg_frac = readl_relaxed(zx_audio_div->reg_base);
399	reg_int = readl_relaxed(zx_audio_div->reg_base + 0x4);
400
401	return audio_calc_rate(zx_audio_div, reg_frac, reg_int, parent_rate);
402}
403
404static long zx_audio_div_round_rate(struct clk_hw *hw, unsigned long rate,
405				unsigned long *prate)
406{
407	struct clk_zx_audio_divider *zx_audio_div = to_clk_zx_audio_div(hw);
408	struct zx_clk_audio_div_table divt;
409
410	audio_calc_reg(zx_audio_div, &divt, rate, *prate);
411
412	return audio_calc_rate(zx_audio_div, divt.frac_reg, divt.int_reg, *prate);
413}
414
415static int zx_audio_div_set_rate(struct clk_hw *hw, unsigned long rate,
416				    unsigned long parent_rate)
417{
418	struct clk_zx_audio_divider *zx_audio_div = to_clk_zx_audio_div(hw);
419	struct zx_clk_audio_div_table divt;
420	unsigned int val;
421
422	audio_calc_reg(zx_audio_div, &divt, rate, parent_rate);
423	if (divt.rate != rate)
424		pr_debug("the real rate is:%ld", divt.rate);
425
426	writel_relaxed(divt.frac_reg, zx_audio_div->reg_base);
427
428	val = readl_relaxed(zx_audio_div->reg_base + 0x4);
429	val &= ~0xffff;
430	val |= divt.int_reg | CLK_AUDIO_DIV_INT_FRAC_RE;
431	writel_relaxed(val, zx_audio_div->reg_base + 0x4);
432
433	mdelay(1);
434
435	val = readl_relaxed(zx_audio_div->reg_base + 0x4);
436	val &= ~CLK_AUDIO_DIV_INT_FRAC_RE;
437	writel_relaxed(val, zx_audio_div->reg_base + 0x4);
438
439	return 0;
440}
441
442const struct clk_ops zx_audio_div_ops = {
443	.recalc_rate = zx_audio_div_recalc_rate,
444	.round_rate = zx_audio_div_round_rate,
445	.set_rate = zx_audio_div_set_rate,
446};
447